Low-power red laser and ultraviolet A LED irradiation alters mRNA levels from DNA repair genes in Saccharomyces cerevisiae 

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On the basis of PBM is the absorption of non-ionizing radiation at low-power by the cytochrome c oxidase, producing reactive oxygen species. Such free radicals could cause oxidative damage in DNA, which is repaired by base excision repair (BER) and nucleotide excision repair (NER) mechanisms. Up to date, few studies assessed oxidative damage in DNA as consequence of low-power red lasers and ultraviolet A LED on expression of DNA gene repair. This study aimed to determine the expression of genes related to BER and NER pathways in Saccharomyces cerevisiae after irradiation with low-power red laser and ultraviolet A LED. Cultures of S. cerevisiae were exposed to low-power red laser (660 nm, 21.2 J/cm 2 , 205 s, 99 mW) and ultraviolet A LED (390 nm, 6 J/cm 2 , 205 s, 7 mW), incubated for 1 hour, total mRNA was extracted, cDNA was synthesized, and OGG1, APN1, RAD1 and RAD10 mRNA levels in S. cerevisiae FF18733 were evaluated by RT-qPCR. The results indicated that exposure to low-power red laser does not induce changes in gene expression, but exposure to ultraviolet A LED alone and simultaneously with low-power red laser significantly reduce APN1 and RAD10 mRNA levels in S. cerevisiae . Exposure to low-power red laser could not affect mRNA from BER and NER, but ultraviolet A LED and simultaneous low-power red laser and ultraviolet A LED could decrease gene expression of BER and NER pathways in S. cerevisiae . DNA repair laser light-emitting diode photobiomodulation yeast Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Non-ionizing radiation at wavelengths emitted by low-power lasers and LEDs is absorbed by a wide range of molecules in biological tissues affecting the activity of cellular structures, signaling molecules, and biological processes and inducing what is known as photobiomodulation (PBM). Over the years PBM has been proposed as a therapeutic strategy due to its potential to stimulate or inhibit biological processes, which include many applications in health, such as wound healing [ 1 ], pain relief [ 2 ], and inflammation management [ 3 ]. The main mechanism of action of PBM involves the absorption of photons at specific wavelengths, which are absorbed by endogenous photoacceptors, notably by cytochrome c oxidase (CCO), which dissociates from nitric oxide (NO) and subsequently stimulates mitochondrial activity leading to the synthesis of adenosine triphosphate (ATP), generation of reactive oxygen species (ROS) and alteration of calcium ions (Ca + 2 ) function [ 4 ]. Furthermore, other photoacceptors such as water, porphyrins, flavins, and opsins can also absorb photons [ 5 ]. Each photoacceptor absorbs at a specific radiation wavelength range. The low-power red laser (from 600 to 700 nm) is one of the most common light sources used to induce PBM [ 6 ] due to radiations in this range being absorbed by CCO. Ultraviolet A LED has been proposed to treat skin disorders [ 7 ] and infections [ 8 ]. As clinical protocols based on PBM are increasing and used worldwide, it is essential to consider its safety both for professionals and patients. For instance, while ROS generation after exposure to low-power red lasers can serve as signaling molecules for cellular processes at low levels, excessive ROS can induce oxidative damage to cellular components, including DNA [ 9 ]. When a DNA molecule is damaged, immediate repair is necessary to maintain genomic stability and homeostasis. The primary mechanism to respond to DNA damage, particularly from chemical sources such as ROS, is the base excision repair (BER) [ 10 ]. The BER mechanism comprises enzymes responsible for identifying and excising damaged bases and restoring DNA integrity from oxidative damage [ 11 ]. Another mechanism known as nucleotide excision repair (NER) is believed to fix DNA from oxidative damage. It is the central system responsible for restoring DNA from damage caused by ultraviolet radiation [ 12 ]. Although these repair mechanisms are well understood, few studies have evaluated the effects of PBM on the expression of genes involved in such DNA repair mechanisms. Given that PBM could modify or be part of DNA repair, evaluation of gene expression related to such processes could be targeted to improve actual and develop new therapeutics. Thus, this study aims to assess the effects of a low-power red laser and an ultraviolet A LED on the expression of repair genes in S. cerevisiae 's BER and NER pathways. Materials and Methods S. cerevisiae culture Cultures of S. cerevisiae FF18733, proficient in DNA repair mechanisms, were grown in YPD medium (yeast extract 10 g/L, peptone 10 g/L, dextrose 20 g/L). For the experiment, the cellular suspension was prepared by cultivating a 10 mL culture overnight (30°C, 120 rpm, 24h), centrifuged (3396 xg, 10 min), washing twice and suspending in sterile phosphate-buffer saline solution (PBS) (KH 2 PO 4 0.23 g/L; NaCl 8.64 g/L; Na 2 HPO 4 0.81 g/L). Low-power laser and LED irradiation The device model Hygialux LLT 1601 was purchased from KLD biosistemas (São Paulo, Brazil). The radiation source was a cluster (emitter applicator CLPE390A660) with a low-power red laser and eight ultraviolet A LEDs. The emission mode was continuous wave for both laser and LED. The fluences used were those suggested by the manufacturer's guide for vitiligo treatment. The physical parameters used are shown in Table 1 . These parameters are indicated and guaranteed by the equipment manual. Table 1 Physical parameters of low-power red laser and ultraviolet A LED Radiation source Wavelength(nm) Power (mW) Fluence (J/cm 2 ) Irradiation time (s) Red laser 660 99 21.2 205 Ultraviolet A LED 390 7 6 205 Aliquots of the cell suspensions in the exponential growth phase (10 7 cells/mL) were divided into equal volumes in tubes (10 mL) and centrifuged (3396 xg, 20°C, 10 min). Then, the cell pellets were exposed at 7 cm from the laser-LED cluster: (i) red laser (21.2 J/cm 2 ), (ii) blue LED (6 J/cm 2 ), (iii) simultaneous red laser and ultraviolet A LED (21.2 + 6 J/cm 2 ). After a single exposure was carried out, the cell pellets were incubated in YPD medium (30°C, 120 rpm, 1h). The incubation time after exposure was determined considering the time of S. cerevisiae cell proliferation [ 13 ]. After the incubation, RT-qPCR was carried out. Cell suspensions not exposed to laser and LED, alone or simultaneously, were used as controls. Total RNA extraction, cDNA synthesis and RT-qPCR reactions Total RNA from samples was extracted by a yeast mRNA extraction kit (Quick-RNA™ Fungal/Bacterial Miniprep, Zymo Research, USA). Briefly, the pellets from each irradiated cellular suspension were suspended in 800 µL RNA Lysis Buffer and transferred into a ZR BashingBead Lysis Tube. The tube was centrifuged for 1 min (10,000 xg), and the cleared supernatant was transferred into a Zymo-Spin™ IIICG Column in a Collection Tube and centrifuged. An equal volume of ethanol (95–100%) (1:1) was added and mixed well to the flow-through. The mixture was transferred into a Zymo-Spin™ IICR Column in a Collection Tube and centrifuged. 400 µl RNA Prep Buffer was added to the column, centrifuged, and the flow-through was discarded. 700 µl RNA Wash Buffer was added to the column, centrifuged, and the flow-through was discarded. 400 µl RNA Wash Buffer was added to the column and centrifuged the column for 1 minute. Then, the column was transferred into a nuclease-free tube. Finally, 50 µl DNase/RNase-Free Water was added directly to the column matrix and centrifuged. The eluted RNA was stored frozen. Total RNA concentration and integrity were determined on a spectrophotometer by calculating the optical density ratio at 260 and 280 nm wavelengths. Complementary DNA (cDNA) synthesis was performed using SuperScript™ IV reverse transcriptase kit (Thermo, USA). Two micrograms of total RNA were reverse transcribed into cDNA using SuperScript™ IV reverse transcriptase (Thermo, USA) according to the manufacturer’s protocol using a complete reaction of 20 µL. To determine the relative quantity of cDNA, samples were amplified for OGG1, APN1, RAD1, and RAD10 (see primer sequences in Table 2 ). Reactions were carried out on a Qiagen 7500 RT-qPCR machine (Qiagen, USA). The mixtures were initially denatured at 94°C for 10 minutes. The PCR consisted of 40 cycles under the following conditions: denaturation at 94°C for 30 seconds, annealing at 61°C for 30 seconds, and extension period at 72°C for 30 seconds. Melt curve analyses were performed for all genes, and the specificity and integrity of the PCR products were confirmed by the presence of a single peak [ 14 ]. Relative expression was normalized by the reference gene (UBC6) levels, and the non-irradiated sample was used as a control group. Duplicate CT values were analyzed in Microsoft Excel (Microsoft) using the comparative CT (2 − ΔΔCT) method [ 15 ]. Table 2 Sequences of the prepared primers Primer name Sequence Source UBC6 Forward Reverse 5’-GATACTTGGAATCCTGGCTG-3’ 5’-CTGTTTCATCACCTGTATTTGC-3’ BMC Molecular Biology 2009, 10:99 doi: 10.1186/1471-2199-10-99 OGG1 Forward Reverse 5’-TGAAGACGTTAGAGAGCACC-3’ 5’-AGATGGTTCTTGTTCGCAGA-3’ - APN1 Forward Reverse 5’-TGGGTTTCTCCGCAGTAT-3’ 5’-GCCTATCCCTAATTGCTCAC-3’ Toxins 2020, 12, 667; doi: 10.3390/toxins12100667 RAD1 Forward Reverse 5’-GCAAATCTGTCCCATCACT-3’ 5’-GTGTATCCACAATGACGA-3’ The EMBO journal, 21(11), 2833–2841. https://doi.org/10.1093/emboj/21.11.2833 RAD10 Forward Reverse 5’-GAACCGCAAACATCAAGACG-3’ 5’-TGGTGCTCTTTAAGTGGTTCA-3’ - Statistical analysis The experimental data were evaluated for normality by the Kolmogorov-Smirnov test. Data that followed normal distribution were analyzed using the ANOVA test and the Tuckey test as a post-test. Data that did not follow the normal distribution were analyzed using the Kruskal–Wallis test and the Dunn test as a post-test. Differences between groups were considered significant when p < 0.05. Statistical tests were performed using InStat Graphpad software (GraphPad InStat version 9.0 for Windows 10, GraphPad Prism Software). Results Relative mRNA levels from genes related to base excision repair in S. cerevisiae after exposure to low-power red laser and ultraviolet A LED To determine if the exposure to low-power red laser and ultraviolet A LED, alone or simultaneously, alters mRNA expression of BER and NER repair genes, OGG1, APN1, RAD1, and RAD10 mRNA expression was evaluated. Figure 1 shows the values of relative OGG1 mRNA levels. Data in this figure suggest that exposure to low-power red laser, ultraviolet A LED, and simultaneous red laser and ultraviolet A LED did not significantly change (p > 0.05) the OGG1 mRNA relative levels. Figure 2 shows the values of relative APN1 mRNA levels. Data in this figure suggest that exposure to low-power red laser (p > 0.05) did not change mRNA levels of RAD10, but ultraviolet A LED (p < 0.05) and simultaneous red laser and ultraviolet A LED (p < 0.01) significantly change the APN1 mRNA relative levels. Relative mRNA levels from genes related to nucleotide excision repair in S. cerevisiae after exposure to low-power red laser and ultraviolet A LED Figure 3 shows the values of relative RAD1 mRNA levels. Data in this figure suggest that exposure to low-power red laser, ultraviolet A LED, and simultaneous red laser and ultraviolet A LED did not significantly change (p > 0.05) the RAD1 mRNA relative levels. Figure 4 shows the values of relative RAD10 mRNA levels. Data in this figure suggest that exposure to low-power red laser (p > 0.05) did not change mRNA levels of RAD10, but ultraviolet A LED (p < 0.05) and simultaneous red laser and ultraviolet A LED (p < 0.05) significantly changed the RAD10 mRNA relative levels. Discussion Due to the PBM effect, various lasers and LEDs, emitting radiations at different wavelengths and fluences, have been used for therapeutic purposes [ 7 , 16 – 18 ]. Some studies showed that PBM can alter the expression of genes [ 19 – 21 ] depending on the biological system exposed and irradiation parameters [ 22 – 23 ]. As PBM could increase oxidative stress and lead to DNA oxidative damage, the expression of genes involved in BER and NER pathways in S. cerevisiae was evaluated after exposure to low-power red laser and ultraviolet A LED. Our results indicate that the exposure to a low-power red laser did not affect the expression of any of the evaluated genes. This finding is in contrast with those of Trajano and coworkers [ 19 ], who reported that the red laser irradiation of burned skin of Wistar rats during wound healing increased the expression of OGG1 and decreased the expression of APE1, a counterpart of yeast APN1 gene. In addition, Sergio and coworkers [ 23 ] pointed to the differential expression of genes related to base excision repair in Wistar rat skin and muscle after exposure to the low-power red laser. Results from this study show that ERCC1 mRNA expression does not alter, but ERCC2 mRNA expression decreases in the skin and increases in muscle tissue exposed to the red laser. Besides, Fonseca and coworkers [ 24 ] reported that low-power red laser can modify the expression of genes related to the nucleotide excision repair pathway, such as XPA and XPC, at fluences and wavelengths used in clinical protocols. Moreover, Farias and coworkers [ 21 ] also reported that low-power red laser can affect the expression of the human genes APTX, POLβ, and PCNA, involved in BER short and long routes. On the other hand, when the cells were exposed to ultraviolet A LED alone or simultaneously to red laser, there was no effect on the expression of OGG1 and RAD1, but there was a decrease of mRNA levels from APN1 and RAD10 genes. APN1 (apurinic/apyrimidinic endonuclease 1) gene encodes an enzyme with many molecular functions, such as 3’-phosphodiesterase and AP-endonuclease activity. Apn1 enzyme plays an essential role in cellular homeostasis since it participates in BER by repairing abasic sites and ROS-induced damage [ 25 – 26 ]. RAD10 is a gene that encodes a protein, which forms, in addition to rad1 and other proteins, an enzymatic complex of the incision step of NER. This protein is sensitive to UV-induced damage [ 27 ]. When exposure occurred simultaneously, the decreasing effect was higher, which suggests that there could be a synergism between these radiations in the production of the transcripts of these genes. This is the first time the effects of simultaneous low-power red laser and ultraviolet A LED exposure on genes involved in BER and NER mechanisms have been evaluated. These findings are relevant because this combination of laser and LED irradiation can modulate the DNA repair mechanism dependent on ultraviolet A radiation. The discrepancies between those from the literature and our data on the mRNA levels from genes related to DNA repair in S. cerevisiae could be explained due to the different photoacceptors or concentrations of photoacceptors in the different cell types used as models. Also, the irradiation conditions, such as fluence and power, could explain these discrepancies. The results obtained in this study confirm that ultraviolet A emitted from therapeutic LED modulates mRNA levels from DNA repair genes in S. cerevisiae . Conclusion While low-power red laser exposure at therapeutic fluences did not alter the mRNA levels from genes related to base excision and nucleotide excision pathways of DNA repair in S. cerevisiae , exposure to ultraviolet A LED could decrease APN1 and RAD10 mRNA levels. These findings are relevant due to the ability of a therapeutic low-power ultraviolet A radiation to modulate the DNA repair mechanisms. Declarations Funding Declaration This study was supported by the Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Científico e Tecnológico, and Universidade do Estado do Rio de Janeiro. Ethics approval: Not applicable. Conflict of interest: The authors declare no competing interests. Author Contribution All authors contributed to the manuscript. References Astuti SD, Sulistyo A, Setiawatie EM, Khasanah M, Purnobasuki H, Arifanto D, Susilo Y, Alamsyah KA, Suhariningsih SA (2022) An in-vivo study of photobiomodulation using 403 nm and 649 nm diode lasers for molar tooth extraction wound healing in wistar rats. Odontology 110:240–253. https://doi.org/10.1007/s10266-021-00653-w Pigatto GR, Silva CS, Parizotto NA (2019) Photobiomodulation therapy reduces acute pain and inflammation in mice. J Photochem Photobiol B 196:111513. https://doi.org/10.1016/j.jphotobiol.2019.111513 Souza NHC, Mesquita-Ferrari RA, Rodrigues MFSD, da Silva DFT, Ribeiro BG, Alves AN, Garcia MP, Nunes FD, da Silva Junior EM, França CM, Bussadori SK, Fernandes KPS (2018) Photobiomodulation and different macrophages phenotypes during muscle tissue repair. J Cell Mol Med 22:4922–4934. https://doi.org/10.1111/jcmm.13757 Dompe C, Moncrieff L, Matys J, Grzech-Leśniak K, Kocherova I, Bryja A, Bruska M, Dominiak M, Mozdziak P, Skiba THI, Shibli JA, Angelova Volponi A, Kempisty B, Dyszkiewicz-Konwińska M (2020) Photobiomodulation-Underlying Mechanism and Clinical Applications. J Clin Med 9(6):1724. https://doi.org/10.3390/jcm9061724 Ramakrishnan P, Joshi A, Fazil M, Yadav P (2024) A comprehensive review on therapeutic potentials of photobiomodulation for neurodegenerative disorders. Life sciences 336:122334. https://doi.org/10.1016/j.lfs.2023.122334 Hamblin MR (2018) Photobiomodulation for traumatic brain injury and stroke. J Neurosci Res 96(4):731-743. https://doi.org/10.1002/jnr.24190 Erratum in: J Neurosci Res. 2019 97(3):373. https://doi.org/10.1002/jnr.24376 Robatto M, Pavie MC, Garcia I, Menezes MP, Bastos M, Leite HJD, Noites A, Lordelo P (2019) Ultraviolet A/blue light-emitting diode therapy for vulvovaginal candidiasis: a case presentation. Lasers Med Sci 34:1819–1827. https://doi.org/10.1007/s10103-019-02782-9 Wi HS, Na EY, Yun SJ, Lee JB (2012) The antifungal effect of light emitting diode on Malassezia yeasts. J Dermatol Sci 67:3–8. https://doi.org/10.1016/j.jdermsci.2012.04.001 Jomova K, Raptova R, Alomar SY, Alwasel SH, Nepovimova E, Kuca K, Valko M (2023) Reactive oxygen species, toxicity, oxidative stress, and antioxidants: chronic diseases and aging. Arch Toxicol 97(10):2499-2574. https://doi.org/10.1007/s00204-023-03562-9 Whitaker AM, Schaich MA, Smith MR, Flynn TS, Freudenthal BD (2017) Base excision repair of oxidative DNA damage: from mechanism to disease. Front Biosci 22(9):1493-1522. https://doi.org/10.2741/4555 Gohil D, Sarker AH, Roy R (2023) Base Excision Repair: Mechanisms and Impact in Biology, Disease, and Medicine. Int J Mol Sci 24(18):14186. https://doi.org/10.3390/ijms241814186 Lee TH, Kang TH (2019) DNA Oxidation and Excision Repair Pathways. Int J Mol Sci 20(23):6092. https://doi.org/10.3390/ijms20236092 Salari R, Salari R (2017) Investigation of the Best Saccharomyces cerevisiae Growth Condition. Electron Physician 9(1):3592-3597. https://doi.org/10.19082/3592 Bustin SA, Benes V, Garson JA, Hellemans J, Huggett J, Kubista M, Mueller R, Nolan T, Pfaffl MW, Shipley GL, Vandesompele J, Wittner CT (2009) The MIQE guidelines: minimum information for publication of quantitative real-time PCR experiments. Clin Chem 55:611–622. https://doi.org/10.1373/clinchem.2008.112797 Livak KJ, Schmittgen TD (2001) Analysis of relative gene expression data using real-time quantitative PCR and the 2ΔΔC(T) Method. Methods 25:402–408. https://doi.org/10.1006/meth.2001.1262 Hamouda AA, El-Habashy LM, Khalil A (2024) The use of laser photobiomodulation as pre-anesthetic tissue management technique in reducing injection pain in children. BMC Oral Health 24:717. https://doi.org/10.1186/s12903-024-04430-3 Ye H, Xiang Y (2024) Clinical Efficacy of 830 nm LED Photobiomodulation Therapy on Postoperative Blepharoplasty Complications. Aesth Plast Surg. https://doi.org/10.1007/s00266-024-04374-7 Abdulrashid NA, Ali OI, Elsharkawy M (2024) Effect of photobiomodulation therapy on headache, and fatigue in patients with chronic rhinosinusitis: a randomized controlled study. Lasers Med Sci 39:62. https://doi.org/10.1007/s10103-024-04011-4 Trajano ET, Mencalha AL, Monte-Alto-Costa A, Pôrto LC, de Souza da Fonseca A (2014) Expression of DNA repair genes in burned skin exposed to low-level red laser. Lasers Med Sci 29(6):1953–1957. https://doi.org/10.1007/s10103-014-1612-6 de Souza da Fonseca A, de Souza Alves E, de Paoli F, Mencalha AL (2022) Low-power therapeutic lasers on mRNA levels. Lasers Med Sci 37:2353–2362. https://doi.org/10.1007/s10103-022-03541-z Farias TG, Rodrigues JA, Dos Santos MS, Mencalha AL, de Souza da Fonseca A (2024) Effects of low-power red laser and blue LED on mRNA levels from DNA repair genes in human breast cancer cells. Lasers Med Sci 39(1):56. https://doi.org/10.1007/s10103-024-04001-6 de Souza da Fonseca A, Mencalha AL, Araújo de Campos VM, Ferreira Machado SC, de Freitas Peregrino AA, Geller M, de Paoli F (2013) DNA repair gene expression in biological tissues exposed to low-intensity infrared laser. Lasers Med Sci 28(4):1077–1084. https://doi.org/10.1007/s10103-012-1191-3 Sergio LP, Campos VM, Vicentini SC, Mencalha AL, de Paoli F, Fonseca AS (2016) Low-intensity red and infrared lasers affect mRNA expression of DNA nucleotide excision repair in skin and muscle tissue. Lasers Med Sci 31(3):429–435. https://doi.org/10.1007/s10103-016-1870-6 Fonseca AS, Magalhães LAG, Mencalha AL, Ferreira-Machado SC, Geller M, Paoli F (2014) Low-intensity red and infrared lasers on XPA and XPC gene expression. Laser Phys Lett 11:095601 https://doi.org/10.1088/1612-2011/11/9/095601 Boiteux S, Guillet M (2004) Abasic sites in DNA: repair and biological consequences in Saccharomyces cerevisiae. DNA repair 3(1):1–12. https://doi.org/10.1016/j.dnarep.2003.10.002 Ho R, Rachek LI, Xu Y, Kelley MR, LeDoux SP, Wilson GL (2007) Yeast apurinic/apyrimidinic endonuclease Apn1 protects mammalian neuronal cell line from oxidative stress. J Neurochem 102(1):13–24. https://doi.org/10.1111/j.1471-4159.2007.04490.x Prakash S, Prakash L (2000) Nucleotide excision repair in yeast. Mutation research 451(1-2):13–24. https://doi.org/10.1016/s0027-5107(00)00037-3 Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5829282","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":403493039,"identity":"999d5595-5ce7-4ba8-8e01-b3619c950115","order_by":0,"name":"Brenno de Mendonça Nunes","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA+ElEQVRIiWNgGAWjYBACAwQzAURIyIHIAw9I0GJhDNaSQIKWisQGOBsHMJc+fOxxQcU2OXP25GMPftRIpM8PO/wQaIudnG4Ddi2WfWnpxjPO3Da27HmWbthzTCJ34+00A6CWZGOzAzgcdobHTJq37Xbihhs5ZtIMbEAtsxNAWg4kbsOphf8bSEs9RMs/iXTD2ekfCGjhYQNpSTAAaWFsk0iQl87Bb4tlD5uZNM+Z24YbzjxLk+ztkzDcIJ1TcCDBALdfzHmYn0nzVNyWNziefEzix7c6efnZ6Zs/fKiwk8OlBYtTwSoNCKhCAfINpKgeBaNgFIyCkQAAZKdfZ1dgerkAAAAASUVORK5CYII=","orcid":"","institution":"Universidade do Estado do Rio de Janeiro, Brazil","correspondingAuthor":true,"prefix":"","firstName":"Brenno","middleName":"de Mendonça","lastName":"Nunes","suffix":""},{"id":403493040,"identity":"baa3aae0-c3fa-4270-8f7d-cc695755fb78","order_by":1,"name":"Daphne Pinheiro","email":"","orcid":"","institution":"Universidade do Estado do Rio de Janeiro, Brazil","correspondingAuthor":false,"prefix":"","firstName":"Daphne","middleName":"","lastName":"Pinheiro","suffix":""},{"id":403493041,"identity":"56254dd3-9787-48a4-8189-afeedb65631f","order_by":2,"name":"Márcia Betânia Nunes de Oliveira","email":"","orcid":"","institution":"Universidade do Estado do Rio de Janeiro, Brazil","correspondingAuthor":false,"prefix":"","firstName":"Márcia","middleName":"Betânia Nunes","lastName":"de Oliveira","suffix":""},{"id":403493042,"identity":"7ab5e8a6-932f-4a2e-a834-757b4a63271c","order_by":3,"name":"Bruno Ricardo Barreto Pires","email":"","orcid":"","institution":"Universidade do Estado do Rio de Janeiro, Brazil","correspondingAuthor":false,"prefix":"","firstName":"Bruno","middleName":"Ricardo Barreto","lastName":"Pires","suffix":""},{"id":403493043,"identity":"e26bdddf-974f-46f2-b65a-28c6e3800975","order_by":4,"name":"Andre Luiz Mencalha","email":"","orcid":"","institution":"Universidade do Estado do Rio de Janeiro, Brazil","correspondingAuthor":false,"prefix":"","firstName":"Andre","middleName":"Luiz","lastName":"Mencalha","suffix":""},{"id":403493046,"identity":"66467e02-2327-4c60-9c15-3a80275105ce","order_by":5,"name":"Flávio José da Silva Dantas","email":"","orcid":"","institution":"Universidade do Estado do Rio de Janeiro, Brazil","correspondingAuthor":false,"prefix":"","firstName":"Flávio","middleName":"José da Silva","lastName":"Dantas","suffix":""},{"id":403493048,"identity":"c36c1d2f-7713-4ff2-8672-b0ce45be7aac","order_by":6,"name":"Adenilson de Souza da Fonseca","email":"","orcid":"","institution":"Universidade do Estado do Rio de Janeiro, Brazil","correspondingAuthor":false,"prefix":"","firstName":"Adenilson","middleName":"de Souza da","lastName":"Fonseca","suffix":""}],"badges":[],"createdAt":"2025-01-14 18:23:20","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5829282/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5829282/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":74240695,"identity":"b6d92ab7-0984-48cd-86a8-77dfa9350aed","added_by":"auto","created_at":"2025-01-20 09:25:35","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":972933,"visible":true,"origin":"","legend":"\u003cp\u003eRelative levels of OGG1 mRNA in \u003cem\u003eSaccharomyces cerevisiae\u003c/em\u003e after exposure to low-power red laser and ultraviolet A LED, alone or simultaneously. Cultures of \u003cem\u003eS. cerevisiae\u003c/em\u003e FF18733 were irradiated with red laser (21.2 J/cm\u003csup\u003e2\u003c/sup\u003e), ultraviolet A LED (6 J/cm\u003csup\u003e2\u003c/sup\u003e) and with red laser and ultraviolet A LED simultaneously (21.2+6 J/cm\u003csup\u003e2\u003c/sup\u003e) in continuous-wave emission mode. Control group was the non-exposed group (0 J/cm\u003csup\u003e2\u003c/sup\u003e). UBC6 mRNA levels were used as an internal standard for normalization.\u003c/p\u003e","description":"","filename":"Figure1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5829282/v1/a905481fd3a926d016cce09c.jpg"},{"id":74240699,"identity":"b68bf24d-9a29-42ac-9326-58befe77c396","added_by":"auto","created_at":"2025-01-20 09:25:35","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":875624,"visible":true,"origin":"","legend":"\u003cp\u003eRelative levels of APN1 mRNA in \u003cem\u003eSaccharomyces cerevisiae\u003c/em\u003e after exposure to low-power red laser and ultraviolet A LED, alone or simultaneously. Cultures of \u003cem\u003eS. cerevisiae\u003c/em\u003e FF18733 were irradiated with red laser (21.2 J/cm\u003csup\u003e2\u003c/sup\u003e), ultraviolet A LED (6 J/cm\u003csup\u003e2\u003c/sup\u003e) and with red laser and ultraviolet A LED simultaneously (21.2+6 J/cm\u003csup\u003e2\u003c/sup\u003e) in continuous-wave mode emission. Control group was the non-exposed group (0 J/cm\u003csup\u003e2\u003c/sup\u003e). UBC6 mRNA levels were used as an internal standard for normalization. Data distribution was performed using the Kolmogorov-Smirnov test, and comparisons between groups were performed using the Kruskal-Wallis and Dunn tests. *p \u0026lt; 0.05 when compared with control group and **p \u0026lt; 0.01 when compared with control group.\u003c/p\u003e","description":"","filename":"Figure2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5829282/v1/3768863263a2d204f060c7df.jpg"},{"id":74240700,"identity":"00166828-2ddc-4081-a0db-14cb1883b5d2","added_by":"auto","created_at":"2025-01-20 09:25:35","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":863669,"visible":true,"origin":"","legend":"\u003cp\u003eRelative levels of RAD1 mRNA in \u003cem\u003eSaccharomyces cerevisiae\u003c/em\u003e after exposure to low-power red laser and ultraviolet A LED, alone or simultaneously. Cultures of \u003cem\u003eS. cerevisiae\u003c/em\u003e FF18733 were irradiated with red laser (21.2 J/cm\u003csup\u003e2\u003c/sup\u003e), ultraviolet A LED (6 J/cm\u003csup\u003e2\u003c/sup\u003e) and with red laser and ultraviolet A LED simultaneously (21.2+6 J/cm\u003csup\u003e2\u003c/sup\u003e) in continuous-wave mode emission. Control group was the non-exposed group (0 J/cm\u003csup\u003e2\u003c/sup\u003e). UBC6 mRNA levels were used as an internal standard for normalization.\u003c/p\u003e","description":"","filename":"Figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5829282/v1/32c3fac9bc67498501297609.jpg"},{"id":74240706,"identity":"357626d4-47c1-46a8-8768-a2b4ef26f093","added_by":"auto","created_at":"2025-01-20 09:25:35","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":887726,"visible":true,"origin":"","legend":"\u003cp\u003eRelative levels of RAD10 mRNA in \u003cem\u003eSaccharomyces cerevisiae\u003c/em\u003e after exposure to low-power red laser and ultraviolet A LED, alone or simultaneously. Cultures of \u003cem\u003eS. cerevisiae\u003c/em\u003e FF18733 were irradiated with red laser (21.2 J/cm\u003csup\u003e2\u003c/sup\u003e), ultraviolet A LED (6 J/cm\u003csup\u003e2\u003c/sup\u003e) and with red laser and ultraviolet A LED simultaneously (21.2+6 J/cm\u003csup\u003e2\u003c/sup\u003e) in continuous-wave mode emission. Control group was the non-exposed group (0 J/cm\u003csup\u003e2\u003c/sup\u003e). UBC6 mRNA levels were used as an internal standard for normalization. Data distribution was performed using the Kolmogorov-Smirnov test, and comparisons between groups were performed using the ANOVA and Bonferroni tests. *p \u0026lt; 0.05 when compared with control group and **p \u0026lt; 0.01 when compared with control group.\u003c/p\u003e","description":"","filename":"Figure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5829282/v1/0dabf88599ccbe60ed19573d.jpg"},{"id":81604220,"identity":"2a0bc860-875e-476b-94a1-07425ccfe4c4","added_by":"auto","created_at":"2025-04-29 05:09:22","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":4154134,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5829282/v1/db66c18a-a12d-4fcb-a9cc-e6052be26b89.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Low-power red laser and ultraviolet A LED irradiation alters mRNA levels from DNA repair genes in Saccharomyces cerevisiae ","fulltext":[{"header":"Introduction","content":"\u003cp\u003eNon-ionizing radiation at wavelengths emitted by low-power lasers and LEDs is absorbed by a wide range of molecules in biological tissues affecting the activity of cellular structures, signaling molecules, and biological processes and inducing what is known as photobiomodulation (PBM). Over the years PBM has been proposed as a therapeutic strategy due to its potential to stimulate or inhibit biological processes, which include many applications in health, such as wound healing [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], pain relief [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], and inflammation management [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe main mechanism of action of PBM involves the absorption of photons at specific wavelengths, which are absorbed by endogenous photoacceptors, notably by cytochrome c oxidase (CCO), which dissociates from nitric oxide (NO) and subsequently stimulates mitochondrial activity leading to the synthesis of adenosine triphosphate (ATP), generation of reactive oxygen species (ROS) and alteration of calcium ions (Ca\u003csup\u003e+\u0026thinsp;2\u003c/sup\u003e) function [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Furthermore, other photoacceptors such as water, porphyrins, flavins, and opsins can also absorb photons [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Each photoacceptor absorbs at a specific radiation wavelength range. The low-power red laser (from 600 to 700 nm) is one of the most common light sources used to induce PBM [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e] due to radiations in this range being absorbed by CCO. Ultraviolet A LED has been proposed to treat skin disorders [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e] and infections [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAs clinical protocols based on PBM are increasing and used worldwide, it is essential to consider its safety both for professionals and patients. For instance, while ROS generation after exposure to low-power red lasers can serve as signaling molecules for cellular processes at low levels, excessive ROS can induce oxidative damage to cellular components, including DNA [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. When a DNA molecule is damaged, immediate repair is necessary to maintain genomic stability and homeostasis. The primary mechanism to respond to DNA damage, particularly from chemical sources such as ROS, is the base excision repair (BER) [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The BER mechanism comprises enzymes responsible for identifying and excising damaged bases and restoring DNA integrity from oxidative damage [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Another mechanism known as nucleotide excision repair (NER) is believed to fix DNA from oxidative damage. It is the central system responsible for restoring DNA from damage caused by ultraviolet radiation [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Although these repair mechanisms are well understood, few studies have evaluated the effects of PBM on the expression of genes involved in such DNA repair mechanisms. Given that PBM could modify or be part of DNA repair, evaluation of gene expression related to such processes could be targeted to improve actual and develop new therapeutics.\u003c/p\u003e \u003cp\u003eThus, this study aims to assess the effects of a low-power red laser and an ultraviolet A LED on the expression of repair genes in \u003cem\u003eS. cerevisiae\u003c/em\u003e's BER and NER pathways.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003eS. cerevisiae culture\u003c/em\u003e\u003c/h2\u003e \u003cp\u003eCultures of \u003cem\u003eS. cerevisiae\u003c/em\u003e FF18733, proficient in DNA repair mechanisms, were grown in YPD medium (yeast extract 10 g/L, peptone 10 g/L, dextrose 20 g/L). For the experiment, the cellular suspension was prepared by cultivating a 10 mL culture overnight (30\u0026deg;C, 120 rpm, 24h), centrifuged (3396 xg, 10 min), washing twice and suspending in sterile phosphate-buffer saline solution (PBS) (KH\u003csub\u003e2\u003c/sub\u003ePO\u003csub\u003e4\u003c/sub\u003e 0.23 g/L; NaCl 8.64 g/L; Na\u003csub\u003e2\u003c/sub\u003eHPO\u003csub\u003e4\u003c/sub\u003e 0.81 g/L).\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eLow-power laser and LED irradiation\u003c/h3\u003e\n\u003cp\u003eThe device model Hygialux LLT 1601 was purchased from KLD biosistemas (S\u0026atilde;o Paulo, Brazil). The radiation source was a cluster (emitter applicator CLPE390A660) with a low-power red laser and eight ultraviolet A LEDs. The emission mode was continuous wave for both laser and LED. The fluences used were those suggested by the manufacturer's guide for vitiligo treatment. The physical parameters used are shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. These parameters are indicated and guaranteed by the equipment manual.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePhysical parameters of low-power red laser and ultraviolet A LED\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRadiation source\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eWavelength(nm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePower (mW)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eFluence (J/cm\u003csup\u003e2\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003eIrradiation time (s)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRed laser\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e660\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e21.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e205\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUltraviolet A LED\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e390\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e \u003cp\u003e205\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAliquots of the cell suspensions in the exponential growth phase (10\u003csup\u003e7\u003c/sup\u003e cells/mL) were divided into equal volumes in tubes (10 mL) and centrifuged (3396 xg, 20\u0026deg;C, 10 min). Then, the cell pellets were exposed at 7 cm from the laser-LED cluster: (i) red laser (21.2 J/cm\u003csup\u003e2\u003c/sup\u003e), (ii) blue LED (6 J/cm\u003csup\u003e2\u003c/sup\u003e), (iii) simultaneous red laser and ultraviolet A LED (21.2\u0026thinsp;+\u0026thinsp;6 J/cm\u003csup\u003e2\u003c/sup\u003e). After a single exposure was carried out, the cell pellets were incubated in YPD medium (30\u0026deg;C, 120 rpm, 1h). The incubation time after exposure was determined considering the time of \u003cem\u003eS. cerevisiae\u003c/em\u003e cell proliferation [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. After the incubation, RT-qPCR was carried out. Cell suspensions not exposed to laser and LED, alone or simultaneously, were used as controls.\u003c/p\u003e\n\u003ch3\u003eTotal RNA extraction, cDNA synthesis and RT-qPCR reactions\u003c/h3\u003e\n\u003cp\u003eTotal RNA from samples was extracted by a yeast mRNA extraction kit (Quick-RNA\u0026trade; Fungal/Bacterial Miniprep, Zymo Research, USA). Briefly, the pellets from each irradiated cellular suspension were suspended in 800 \u0026micro;L RNA Lysis Buffer and transferred into a ZR BashingBead Lysis Tube. The tube was centrifuged for 1 min (10,000 xg), and the cleared supernatant was transferred into a Zymo-Spin\u0026trade; IIICG Column in a Collection Tube and centrifuged. An equal volume of ethanol (95\u0026ndash;100%) (1:1) was added and mixed well to the flow-through. The mixture was transferred into a Zymo-Spin\u0026trade; IICR Column in a Collection Tube and centrifuged. 400 \u0026micro;l RNA Prep Buffer was added to the column, centrifuged, and the flow-through was discarded. 700 \u0026micro;l RNA Wash Buffer was added to the column, centrifuged, and the flow-through was discarded. 400 \u0026micro;l RNA Wash Buffer was added to the column and centrifuged the column for 1 minute. Then, the column was transferred into a nuclease-free tube. Finally, 50 \u0026micro;l DNase/RNase-Free Water was added directly to the column matrix and centrifuged. The eluted RNA was stored frozen. Total RNA concentration and integrity were determined on a spectrophotometer by calculating the optical density ratio at 260 and 280 nm wavelengths.\u003c/p\u003e \u003cp\u003eComplementary DNA (cDNA) synthesis was performed using SuperScript\u0026trade; IV reverse transcriptase kit (Thermo, USA). Two micrograms of total RNA were reverse transcribed into cDNA using SuperScript\u0026trade; IV reverse transcriptase (Thermo, USA) according to the manufacturer\u0026rsquo;s protocol using a complete reaction of 20 \u0026micro;L.\u003c/p\u003e \u003cp\u003eTo determine the relative quantity of cDNA, samples were amplified for OGG1, APN1, RAD1, and RAD10 (see primer sequences in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Reactions were carried out on a Qiagen 7500 RT-qPCR machine (Qiagen, USA). The mixtures were initially denatured at 94\u0026deg;C for 10 minutes. The PCR consisted of 40 cycles under the following conditions: denaturation at 94\u0026deg;C for 30 seconds, annealing at 61\u0026deg;C for 30 seconds, and extension period at 72\u0026deg;C for 30 seconds. Melt curve analyses were performed for all genes, and the specificity and integrity of the PCR products were confirmed by the presence of a single peak [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Relative expression was normalized by the reference gene (UBC6) levels, and the non-irradiated sample was used as a control group. Duplicate CT values were analyzed in Microsoft Excel (Microsoft) using the comparative CT (2\u0026thinsp;\u0026minus;\u0026thinsp;ΔΔCT) method [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSequences of the prepared primers\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrimer name\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSequence\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSource\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eUBC6\u003c/p\u003e \u003cp\u003eForward\u003c/p\u003e \u003cp\u003eReverse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u0026rsquo;-GATACTTGGAATCCTGGCTG-3\u0026rsquo;\u003c/p\u003e \u003cp\u003e5\u0026rsquo;-CTGTTTCATCACCTGTATTTGC-3\u0026rsquo;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eBMC Molecular Biology 2009, 10:99 doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1186/1471-2199-10-99\u003c/span\u003e\u003cspan address=\"10.1186/1471-2199-10-99\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOGG1\u003c/p\u003e \u003cp\u003eForward\u003c/p\u003e \u003cp\u003eReverse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u0026rsquo;-TGAAGACGTTAGAGAGCACC-3\u0026rsquo;\u003c/p\u003e \u003cp\u003e5\u0026rsquo;-AGATGGTTCTTGTTCGCAGA-3\u0026rsquo;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAPN1\u003c/p\u003e \u003cp\u003eForward\u003c/p\u003e \u003cp\u003eReverse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u0026rsquo;-TGGGTTTCTCCGCAGTAT-3\u0026rsquo;\u003c/p\u003e \u003cp\u003e5\u0026rsquo;-GCCTATCCCTAATTGCTCAC-3\u0026rsquo;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eToxins 2020, 12, 667; doi:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.3390/toxins12100667\u003c/span\u003e\u003cspan address=\"10.3390/toxins12100667\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRAD1\u003c/p\u003e \u003cp\u003eForward\u003c/p\u003e \u003cp\u003eReverse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u0026rsquo;-GCAAATCTGTCCCATCACT-3\u0026rsquo;\u003c/p\u003e \u003cp\u003e5\u0026rsquo;-GTGTATCCACAATGACGA-3\u0026rsquo;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eThe EMBO journal, 21(11), 2833\u0026ndash;2841. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1093/emboj/21.11.2833\u003c/span\u003e\u003cspan address=\"10.1093/emboj/21.11.2833\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRAD10\u003c/p\u003e \u003cp\u003eForward\u003c/p\u003e \u003cp\u003eReverse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5\u0026rsquo;-GAACCGCAAACATCAAGACG-3\u0026rsquo;\u003c/p\u003e \u003cp\u003e5\u0026rsquo;-TGGTGCTCTTTAAGTGGTTCA-3\u0026rsquo;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003eStatistical analysis\u003c/h2\u003e \u003cp\u003eThe experimental data were evaluated for normality by the Kolmogorov-Smirnov test. Data that followed normal distribution were analyzed using the ANOVA test and the Tuckey test as a post-test. Data that did not follow the normal distribution were analyzed using the Kruskal\u0026ndash;Wallis test and the Dunn test as a post-test. Differences between groups were considered significant when \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05. Statistical tests were performed using InStat Graphpad software (GraphPad InStat version 9.0 for Windows 10, GraphPad Prism Software).\u003c/p\u003e \u003c/div\u003e"},{"header":"Results","content":"\u003cp\u003e \u003cem\u003eRelative mRNA levels from genes related to base excision repair in S. cerevisiae after exposure to low-power red laser and ultraviolet A LED\u003c/em\u003e \u003c/p\u003e \u003cp\u003eTo determine if the exposure to low-power red laser and ultraviolet A LED, alone or simultaneously, alters mRNA expression of BER and NER repair genes, OGG1, APN1, RAD1, and RAD10 mRNA expression was evaluated. Figure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e shows the values of relative OGG1 mRNA levels. Data in this figure suggest that exposure to low-power red laser, ultraviolet A LED, and simultaneous red laser and ultraviolet A LED did not significantly change (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05) the OGG1 mRNA relative levels.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e shows the values of relative APN1 mRNA levels. Data in this figure suggest that exposure to low-power red laser (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05) did not change mRNA levels of RAD10, but ultraviolet A LED (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) and simultaneous red laser and ultraviolet A LED (p\u0026thinsp;\u0026lt;\u0026thinsp;0.01) significantly change the APN1 mRNA relative levels.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003e \u003cem\u003eRelative mRNA levels from genes related to nucleotide excision repair in S. cerevisiae after exposure to low-power red laser and ultraviolet A LED\u003c/em\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e shows the values of relative RAD1 mRNA levels. Data in this figure suggest that exposure to low-power red laser, ultraviolet A LED, and simultaneous red laser and ultraviolet A LED did not significantly change (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05) the RAD1 mRNA relative levels.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e shows the values of relative RAD10 mRNA levels. Data in this figure suggest that exposure to low-power red laser (p\u0026thinsp;\u0026gt;\u0026thinsp;0.05) did not change mRNA levels of RAD10, but ultraviolet A LED (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) and simultaneous red laser and ultraviolet A LED (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) significantly changed the RAD10 mRNA relative levels.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eDue to the PBM effect, various lasers and LEDs, emitting radiations at different wavelengths and fluences, have been used for therapeutic purposes [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan additionalcitationids=\"CR17\" citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Some studies showed that PBM can alter the expression of genes [\u003cspan additionalcitationids=\"CR20\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] depending on the biological system exposed and irradiation parameters [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. As PBM could increase oxidative stress and lead to DNA oxidative damage, the expression of genes involved in BER and NER pathways in \u003cem\u003eS. cerevisiae\u003c/em\u003e was evaluated after exposure to low-power red laser and ultraviolet A LED. Our results indicate that the exposure to a low-power red laser did not affect the expression of any of the evaluated genes. This finding is in contrast with those of Trajano and coworkers [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e], who reported that the red laser irradiation of burned skin of \u003cem\u003eWistar\u003c/em\u003e rats during wound healing increased the expression of OGG1 and decreased the expression of APE1, a counterpart of yeast APN1 gene. In addition, Sergio and coworkers [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e] pointed to the differential expression of genes related to base excision repair in Wistar rat skin and muscle after exposure to the low-power red laser. Results from this study show that ERCC1 mRNA expression does not alter, but ERCC2 mRNA expression decreases in the skin and increases in muscle tissue exposed to the red laser. Besides, Fonseca and coworkers [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e] reported that low-power red laser can modify the expression of genes related to the nucleotide excision repair pathway, such as XPA and XPC, at fluences and wavelengths used in clinical protocols. Moreover, Farias and coworkers [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e] also reported that low-power red laser can affect the expression of the human genes APTX, POLβ, and PCNA, involved in BER short and long routes.\u003c/p\u003e \u003cp\u003eOn the other hand, when the cells were exposed to ultraviolet A LED alone or simultaneously to red laser, there was no effect on the expression of OGG1 and RAD1, but there was a decrease of mRNA levels from APN1 and RAD10 genes. APN1 (apurinic/apyrimidinic endonuclease 1) gene encodes an enzyme with many molecular functions, such as 3\u0026rsquo;-phosphodiesterase and AP-endonuclease activity. Apn1 enzyme plays an essential role in cellular homeostasis since it participates in BER by repairing abasic sites and ROS-induced damage [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. RAD10 is a gene that encodes a protein, which forms, in addition to rad1 and other proteins, an enzymatic complex of the incision step of NER. This protein is sensitive to UV-induced damage [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. When exposure occurred simultaneously, the decreasing effect was higher, which suggests that there could be a synergism between these radiations in the production of the transcripts of these genes.\u003c/p\u003e \u003cp\u003eThis is the first time the effects of simultaneous low-power red laser and ultraviolet A LED exposure on genes involved in BER and NER mechanisms have been evaluated. These findings are relevant because this combination of laser and LED irradiation can modulate the DNA repair mechanism dependent on ultraviolet A radiation.\u003c/p\u003e \u003cp\u003eThe discrepancies between those from the literature and our data on the mRNA levels from genes related to DNA repair in \u003cem\u003eS. cerevisiae\u003c/em\u003e could be explained due to the different photoacceptors or concentrations of photoacceptors in the different cell types used as models. Also, the irradiation conditions, such as fluence and power, could explain these discrepancies. The results obtained in this study confirm that ultraviolet A emitted from therapeutic LED modulates mRNA levels from DNA repair genes in \u003cem\u003eS. cerevisiae\u003c/em\u003e.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eWhile low-power red laser exposure at therapeutic fluences did not alter the mRNA levels from genes related to base excision and nucleotide excision pathways of DNA repair in \u003cem\u003eS. cerevisiae\u003c/em\u003e, exposure to ultraviolet A LED could decrease APN1 and RAD10 mRNA levels. These findings are relevant due to the ability of a therapeutic low-power ultraviolet A radiation to modulate the DNA repair mechanisms.\u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003e \u003cb\u003eFunding Declaration\u003c/b\u003e \u003c/p\u003e \u003cp\u003eThis study was supported by the Funda\u0026ccedil;\u0026atilde;o de Amparo \u0026agrave; Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Cient\u0026iacute;fico e Tecnol\u0026oacute;gico, and Universidade do Estado do Rio de Janeiro.\u003c/p\u003e \u003cp\u003e \u003cstrong\u003eEthics approval:\u003c/strong\u003e \u003cp\u003eNot applicable.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eConflict of interest:\u003c/strong\u003e \u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAll authors contributed to the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAstuti SD, Sulistyo A, Setiawatie EM, Khasanah M, Purnobasuki H, Arifanto D, Susilo Y, Alamsyah KA, Suhariningsih SA (2022) An in-vivo study of photobiomodulation using 403 nm and 649 nm diode lasers for molar tooth extraction wound healing in wistar rats. Odontology 110:240\u0026ndash;253. https://doi.org/10.1007/s10266-021-00653-w\u003c/li\u003e\n\u003cli\u003ePigatto GR, Silva CS, Parizotto NA (2019) Photobiomodulation therapy reduces acute pain and inflammation in mice. J Photochem Photobiol B 196:111513. https://doi.org/10.1016/j.jphotobiol.2019.111513\u003c/li\u003e\n\u003cli\u003eSouza NHC, Mesquita-Ferrari RA, Rodrigues MFSD, da Silva DFT, Ribeiro BG, Alves AN, Garcia MP, Nunes FD, da Silva Junior EM, Fran\u0026ccedil;a CM, Bussadori SK, Fernandes KPS (2018) Photobiomodulation and different macrophages phenotypes during muscle tissue repair. J Cell Mol Med 22:4922\u0026ndash;4934. https://doi.org/10.1111/jcmm.13757\u003c/li\u003e\n\u003cli\u003eDompe C, Moncrieff L, Matys J, Grzech-Leśniak K, Kocherova I, Bryja A, Bruska M, Dominiak M, Mozdziak P, Skiba THI, Shibli JA, Angelova Volponi A, Kempisty B, Dyszkiewicz-Konwińska M (2020) Photobiomodulation-Underlying Mechanism and Clinical Applications. J Clin Med 9(6):1724. https://doi.org/10.3390/jcm9061724\u003c/li\u003e\n\u003cli\u003eRamakrishnan P, Joshi A, Fazil M, Yadav P (2024) A comprehensive review on therapeutic potentials of photobiomodulation for neurodegenerative disorders. Life sciences 336:122334. https://doi.org/10.1016/j.lfs.2023.122334\u003c/li\u003e\n\u003cli\u003eHamblin MR (2018) Photobiomodulation for traumatic brain injury and stroke. J Neurosci Res 96(4):731-743. https://doi.org/10.1002/jnr.24190 Erratum in: J Neurosci Res. 2019 97(3):373. https://doi.org/10.1002/jnr.24376\u003c/li\u003e\n\u003cli\u003eRobatto M, Pavie MC, Garcia I, Menezes MP, Bastos M, Leite HJD, Noites A, Lordelo P (2019) Ultraviolet A/blue light-emitting diode therapy for vulvovaginal candidiasis: a case presentation. Lasers Med Sci 34:1819\u0026ndash;1827. https://doi.org/10.1007/s10103-019-02782-9\u003c/li\u003e\n\u003cli\u003eWi HS, Na EY, Yun SJ, Lee JB (2012) The antifungal effect of light emitting diode on Malassezia yeasts. J Dermatol Sci 67:3\u0026ndash;8. https://doi.org/10.1016/j.jdermsci.2012.04.001\u003c/li\u003e\n\u003cli\u003eJomova K, Raptova R, Alomar SY, Alwasel SH, Nepovimova E, Kuca K, Valko M (2023) Reactive oxygen species, toxicity, oxidative stress, and antioxidants: chronic diseases and aging. Arch Toxicol 97(10):2499-2574. https://doi.org/10.1007/s00204-023-03562-9\u003c/li\u003e\n\u003cli\u003eWhitaker AM, Schaich MA, Smith MR, Flynn TS, Freudenthal BD (2017) Base excision repair of oxidative DNA damage: from mechanism to disease. Front Biosci 22(9):1493-1522. https://doi.org/10.2741/4555\u003c/li\u003e\n\u003cli\u003eGohil D, Sarker AH, Roy R (2023) Base Excision Repair: Mechanisms and Impact in Biology, Disease, and Medicine. Int J Mol Sci 24(18):14186. https://doi.org/10.3390/ijms241814186\u003c/li\u003e\n\u003cli\u003eLee TH, Kang TH (2019) DNA Oxidation and Excision Repair Pathways. Int J Mol Sci 20(23):6092. https://doi.org/10.3390/ijms20236092\u003c/li\u003e\n\u003cli\u003eSalari R, Salari R (2017) Investigation of the Best Saccharomyces cerevisiae Growth Condition. Electron Physician 9(1):3592-3597. https://doi.org/10.19082/3592\u003c/li\u003e\n\u003cli\u003eBustin SA, Benes V, Garson JA, Hellemans J, Huggett J, Kubista M, Mueller R, Nolan T, Pfaffl MW, Shipley GL, Vandesompele J, Wittner CT (2009) The MIQE guidelines: minimum information for publication of quantitative real-time PCR experiments. Clin Chem 55:611\u0026ndash;622. https://doi.org/10.1373/clinchem.2008.112797\u003c/li\u003e\n\u003cli\u003eLivak KJ, Schmittgen TD (2001) Analysis of relative gene expression data using real-time quantitative PCR and the 2\u0026Delta;\u0026Delta;C(T) Method. Methods 25:402\u0026ndash;408. https://doi.org/10.1006/meth.2001.1262\u003c/li\u003e\n\u003cli\u003eHamouda AA, El-Habashy LM, Khalil A (2024) The use of laser photobiomodulation as pre-anesthetic tissue management technique in reducing injection pain in children. BMC Oral Health 24:717. https://doi.org/10.1186/s12903-024-04430-3\u003c/li\u003e\n\u003cli\u003eYe H, Xiang Y (2024) Clinical Efficacy of 830 nm LED Photobiomodulation Therapy on Postoperative Blepharoplasty Complications. Aesth Plast Surg. https://doi.org/10.1007/s00266-024-04374-7\u003c/li\u003e\n\u003cli\u003eAbdulrashid NA, Ali OI, Elsharkawy M (2024) Effect of photobiomodulation therapy on headache, and fatigue in patients with chronic rhinosinusitis: a randomized controlled study. Lasers Med Sci 39:62. https://doi.org/10.1007/s10103-024-04011-4\u003c/li\u003e\n\u003cli\u003eTrajano ET, Mencalha AL, Monte-Alto-Costa A, P\u0026ocirc;rto LC, de Souza da Fonseca A (2014) Expression of DNA repair genes in burned skin exposed to low-level red laser. Lasers Med Sci 29(6):1953\u0026ndash;1957. https://doi.org/10.1007/s10103-014-1612-6\u003c/li\u003e\n\u003cli\u003ede Souza da Fonseca A, de Souza Alves E, de Paoli F, Mencalha AL (2022) Low-power therapeutic lasers on mRNA levels. Lasers Med Sci 37:2353\u0026ndash;2362. https://doi.org/10.1007/s10103-022-03541-z\u003c/li\u003e\n\u003cli\u003eFarias TG, Rodrigues JA, Dos Santos MS, Mencalha AL, de Souza da Fonseca A (2024) Effects of low-power red laser and blue LED on mRNA levels from DNA repair genes in human breast cancer cells. Lasers Med Sci 39(1):56. https://doi.org/10.1007/s10103-024-04001-6\u003c/li\u003e\n\u003cli\u003ede Souza da Fonseca A, Mencalha AL, Ara\u0026uacute;jo de Campos VM, Ferreira Machado SC, de Freitas Peregrino AA, Geller M, de Paoli F (2013) DNA repair gene expression in biological tissues exposed to low-intensity infrared laser. Lasers Med Sci 28(4):1077\u0026ndash;1084. https://doi.org/10.1007/s10103-012-1191-3\u003c/li\u003e\n\u003cli\u003eSergio LP, Campos VM, Vicentini SC, Mencalha AL, de Paoli F, Fonseca AS (2016) Low-intensity red and infrared lasers affect mRNA expression of DNA nucleotide excision repair in skin and muscle tissue. Lasers Med Sci 31(3):429\u0026ndash;435. https://doi.org/10.1007/s10103-016-1870-6\u003c/li\u003e\n\u003cli\u003eFonseca AS, Magalh\u0026atilde;es LAG, Mencalha AL, Ferreira-Machado SC, Geller M, Paoli F (2014) Low-intensity red and infrared lasers on XPA and XPC gene expression. Laser Phys Lett 11:095601 https://doi.org/10.1088/1612-2011/11/9/095601\u003c/li\u003e\n\u003cli\u003eBoiteux S, Guillet M (2004) Abasic sites in DNA: repair and biological consequences in Saccharomyces cerevisiae. DNA repair 3(1):1\u0026ndash;12. https://doi.org/10.1016/j.dnarep.2003.10.002\u003c/li\u003e\n\u003cli\u003eHo R, Rachek LI, Xu Y, Kelley MR, LeDoux SP, Wilson GL (2007) Yeast apurinic/apyrimidinic endonuclease Apn1 protects mammalian neuronal cell line from oxidative stress. J Neurochem 102(1):13\u0026ndash;24. https://doi.org/10.1111/j.1471-4159.2007.04490.x\u003c/li\u003e\n\u003cli\u003ePrakash S, Prakash L (2000) Nucleotide excision repair in yeast. Mutation research 451(1-2):13\u0026ndash;24. https://doi.org/10.1016/s0027-5107(00)00037-3\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"DNA repair, laser, light-emitting diode, photobiomodulation, yeast","lastPublishedDoi":"10.21203/rs.3.rs-5829282/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5829282/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eTherapeutic protocols based on photobiomodulation (PBM) have been used to treat wounds, pain, and inflammation. On the basis of PBM is the absorption of non-ionizing radiation at low-power by the cytochrome c oxidase, producing reactive oxygen species. Such free radicals could cause oxidative damage in DNA, which is repaired by base excision repair (BER) and nucleotide excision repair (NER) mechanisms. Up to date, few studies assessed oxidative damage in DNA as consequence of low-power red lasers and ultraviolet A LED on expression of DNA gene repair. This study aimed to determine the expression of genes related to BER and NER pathways in \u003cem\u003eSaccharomyces cerevisiae\u003c/em\u003e after irradiation with low-power red laser and ultraviolet A LED. Cultures of \u003cem\u003eS. cerevisiae\u003c/em\u003e were exposed to low-power red laser (660 nm, 21.2 J/cm\u003csup\u003e2\u003c/sup\u003e, 205 s, 99 mW) and ultraviolet A LED (390 nm, 6 J/cm\u003csup\u003e2\u003c/sup\u003e, 205 s, 7 mW), incubated for 1 hour, total mRNA was extracted, cDNA was synthesized, and OGG1, APN1, RAD1 and RAD10 mRNA levels in \u003cem\u003eS. cerevisiae\u003c/em\u003e FF18733 were evaluated by RT-qPCR. The results indicated that exposure to low-power red laser does not induce changes in gene expression, but exposure to ultraviolet A LED alone and simultaneously with low-power red laser significantly reduce APN1 and RAD10 mRNA levels in \u003cem\u003eS. cerevisiae\u003c/em\u003e. Exposure to low-power red laser could not affect mRNA from BER and NER, but ultraviolet A LED and simultaneous low-power red laser and ultraviolet A LED could decrease gene expression of BER and NER pathways in \u003cem\u003eS. cerevisiae\u003c/em\u003e.\u003c/p\u003e","manuscriptTitle":"Low-power red laser and ultraviolet A LED irradiation alters mRNA levels from DNA repair genes in Saccharomyces cerevisiae ","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-01-20 09:25:30","doi":"10.21203/rs.3.rs-5829282/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"339902a3-7c7e-44e1-bbd1-9268e5b8dab1","owner":[],"postedDate":"January 20th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-04-29T05:09:11+00:00","versionOfRecord":[],"versionCreatedAt":"2025-01-20 09:25:30","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5829282","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5829282","identity":"rs-5829282","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}