Exopolysaccharides extracted from submerged cultures of Ganoderma lucidumactivate the NLRP3 inflammasome

Exopolysaccharides extracted from submerged cultures of Ganoderma lucidumactivate the NLRP3 inflammasome | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Exopolysaccharides extracted from submerged cultures of Ganoderma lucidumactivate the NLRP3 inflammasome Pedro Henrique Burguel, Raffael Junio de Almeida Castro, Angelina M. Moreschi Basso, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4751112/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Interleucin-1β (IL-1β) is a pivotal cytokine in pro-inflammatory response induction, and it is regarded as protective in various diseases. IL-1β secretion is mainly associated with activation of the inflammasome complex, which generally is tightly regulated, depending on two signals for significant activity. The water-insoluble fraction of the mushroom Ganoderma lucidum was extracted and co-cultivated with murine bone marrow macrophages. We demonstrated that G. lucidum exopolysaccharides (EPS) could induce IL-1β production and release in murine macrophages. The mechanisms underlying EPS-induced priming encompass recognition through dectin-1 and activation of the spleen tyrosine kinase (Syk) / nuclear factor kappa-light-chain-enhancer of the activated B (NF-kB) axis. In addition, EPS stimulates IL-1β secretion in a phagocytosis-dependent manner via the NLR family pyrin domain containing 3 (NLRP3) inflammasome activation in response to reactive oxygen species production, potassium efflux, phagolysosomal acidification, and cathepsin B release. Both caspase-1 and, to a lesser extent, caspase-8 were activated upon EPS stimulus and required for IL-1β cleavage and release. The treatment with EPS by gavage of Cryptococcus neoformans-infected mice showed increased survival. Our study highlighted significant stimulation by G. lucidum EPS to innate immune cells, suggesting a potential adjuvant in antimicrobial treatment schemes. inflammasome Ganoderma polysaccharides NLRP3 innate immunity Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Full Text Supplementary Files FigureS1.tif Fig. S1. Evaluation of the monosaccharide constituents of EPS extracted from Ganoderma lucidum. The analysis was carried out using the GC-MS technique of the monosaccharide constituents of the soluble (A) and insoluble (B) fractions of G. lucidum. Fuc – Fucose; Xyl – Xylose; Man – Mannose; Glc – Glucose; Gal – Galactose; Rib – Ribose; Ara – Arabinose. 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. 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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-4751112","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":337201183,"identity":"82e2c7b4-9044-42a6-8f7a-a8d51534af3c","order_by":0,"name":"Pedro Henrique Burguel","email":"","orcid":"","institution":"Universidade de Brasília: Universidade de Brasilia","correspondingAuthor":false,"prefix":"","firstName":"Pedro","middleName":"Henrique","lastName":"Burguel","suffix":""},{"id":337201184,"identity":"a57cc4a1-edfc-41ed-95b5-d6eca4251809","order_by":1,"name":"Raffael Junio de Almeida Castro","email":"","orcid":"","institution":"Universidade de Brasilia Instituto de Ciências Biológicas: Universidade de Brasilia Instituto de Ciencias Biologicas","correspondingAuthor":false,"prefix":"","firstName":"Raffael","middleName":"Junio de Almeida","lastName":"Castro","suffix":""},{"id":337201185,"identity":"324ff6ef-cf0a-41d2-af0e-227f271ab960","order_by":2,"name":"Angelina M. Moreschi Basso","email":"","orcid":"","institution":"Universidade de Brasilia","correspondingAuthor":false,"prefix":"","firstName":"Angelina","middleName":"M. Moreschi","lastName":"Basso","suffix":""},{"id":337201186,"identity":"9e96d848-0a1e-42e5-b3fc-d6ffd3d8755c","order_by":3,"name":"Luisa Coelho Coutinho","email":"","orcid":"","institution":"Universidade de Brasilia Instituto de Ciências Biológicas: Universidade de Brasilia Instituto de Ciencias Biologicas","correspondingAuthor":false,"prefix":"","firstName":"Luisa","middleName":"Coelho","lastName":"Coutinho","suffix":""},{"id":337201187,"identity":"31fdddd9-2549-478b-a33f-1198ce874ccb","order_by":4,"name":"Clara Luna Freitas Marina","email":"","orcid":"","institution":"University of Brasilia: Universidade de Brasilia","correspondingAuthor":false,"prefix":"","firstName":"Clara","middleName":"Luna Freitas","lastName":"Marina","suffix":""},{"id":337201188,"identity":"dac63f8d-06d8-41d8-bb44-0eb986a95325","order_by":5,"name":"Isaque Medeiros Siqueira","email":"","orcid":"","institution":"UnB: Universidade de Brasilia","correspondingAuthor":false,"prefix":"","firstName":"Isaque","middleName":"Medeiros","lastName":"Siqueira","suffix":""},{"id":337201189,"identity":"6f7a16c9-67c2-488a-a120-8f0d49628e07","order_by":6,"name":"Alysia Gonzales Gonzales","email":"","orcid":"","institution":"University of Mississippi School of Pharmacy","correspondingAuthor":false,"prefix":"","firstName":"Alysia","middleName":"Gonzales","lastName":"Gonzales","suffix":""},{"id":337201190,"identity":"ab2228b7-0d7c-40b4-a5d1-9371c98687bc","order_by":7,"name":"Pavel Kucheryavy","email":"","orcid":"","institution":"University of Mississippi School of Pharmacy","correspondingAuthor":false,"prefix":"","firstName":"Pavel","middleName":"","lastName":"Kucheryavy","suffix":""},{"id":337201191,"identity":"e57c7533-1435-4e4c-ac64-9c84d43d0a75","order_by":8,"name":"Vitor H Pomin","email":"","orcid":"","institution":"University of Mississippi School of Pharmacy","correspondingAuthor":false,"prefix":"","firstName":"Vitor","middleName":"H","lastName":"Pomin","suffix":""},{"id":337201192,"identity":"47847c9a-9e8d-4316-bf60-36d763c2166c","order_by":9,"name":"Elaine Rosecher Carbonero","email":"","orcid":"","institution":"Universidade Federal de Catalao","correspondingAuthor":false,"prefix":"","firstName":"Elaine","middleName":"Rosecher","lastName":"Carbonero","suffix":""},{"id":337201193,"identity":"684991d2-4555-4a96-b619-66cf1f221be4","order_by":10,"name":"Aldo Henrique Tavares","email":"","orcid":"","institution":"Universidade de Brasilia","correspondingAuthor":false,"prefix":"","firstName":"Aldo","middleName":"Henrique","lastName":"Tavares","suffix":""},{"id":337201194,"identity":"da458659-29b3-455e-8d5c-921f03de57e2","order_by":11,"name":"Anamelia Lorenzetti Bocca","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAm0lEQVRIiWNgGAWjYDACdh4wJcfAwMPATJwWZogWY9K1JDYQrYW/mffggx81dukbbvceYC7cQ4QWicN8yYY9x5JzN9w5l8A84xkx1hzmMZNmbGDO3XAjx4CZ5wAROuQhWurTDYjWYgDRcjiBeC2GEL8cN5x5Iy/h8AxitMgd7wWFWLU8343cg48LiNGCAkjWMApGwSgYBaMABwAAkogzksTJf0oAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0003-3323-5300","institution":"Universityof Brasilia","correspondingAuthor":true,"prefix":"","firstName":"Anamelia","middleName":"Lorenzetti","lastName":"Bocca","suffix":""}],"badges":[],"createdAt":"2024-07-16 16:16:17","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4751112/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4751112/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":63848647,"identity":"51ef8946-b4e8-4d9d-b254-cb6283f74dea","added_by":"auto","created_at":"2024-09-03 03:26:42","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":178389,"visible":true,"origin":"","legend":"\u003cp\u003eG. lucidum exopolysaccharides 1D structural analysis. 1D 1H NMR spectra (δH \u0026nbsp;expansion between 5.40 and 3.05 ppm) of (A) standard monosaccharides, galactose (Gal, \u0026nbsp;blue), glucose (Glc, black), and mannose (Man, red), all overlapped, and, (B) insoluble \u0026nbsp;fraction from Ganoderma lucidum glucan indicating the resonances belonging to the \u0026nbsp;individual monosaccharide components. Signals are labeled by monosaccharides’ three-letter \u0026nbsp;abbreviation followed by the Greek letter of the anomeric ring form (α or β) and the number \u0026nbsp;of the atomic position within the hexose ring.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/8051780d40bbd6eec582505a.png"},{"id":63848651,"identity":"5f861af5-a3e7-45d2-a925-146561bd971e","added_by":"auto","created_at":"2024-09-03 03:26:48","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":485460,"visible":true,"origin":"","legend":"\u003cp\u003eG. lucidum exopolysaccharides 2D structural analysis. 2D 1H–1H NOESY spectra \u0026nbsp;(δH-δH/δH-δH expansions between 5.20-3.0/5.37-3.0 ppm) at different counter-levels, (A) \u0026nbsp;higher and (B) lower threshold, for assessment of through-space (A) intraresidue and (B) \u0026nbsp;inter-residue proton-proton connectivities of the insoluble fraction from Ganoderma lucidum glucan. Signals are labeled by monosaccharide type (Glc, for glucose; \u0026nbsp;Gal, for galactose; and \u0026nbsp;Man, for mannose) followed by the Greek letter of the ring anomeric form (α or β) and the \u0026nbsp;number of the atomic position within the hexose ring.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/a5dbd9b7da335685762c6e90.png"},{"id":63848642,"identity":"49aa6877-27d5-4982-b02e-b4cdb3154e4c","added_by":"auto","created_at":"2024-09-03 03:26:41","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":131713,"visible":true,"origin":"","legend":"\u003cp\u003eG. lucidum EPS promote phagocytosis-dependent IL-1β secretion in BMDMs. \u0026nbsp;Intracellular Il1b and Tnfa mRNA of BMDMs after 6 h stimulation with EPS or LPS (positive \u0026nbsp;control) were analyzed by RT-qPCR (A). Pro-IL-1β was assayed in the cell lysate by ELISA \u0026nbsp;after 10h of stimulation with EPS (100μg/mL) or LPS (500 ng/mL) and nigericin (20 μM \u0026nbsp;during the last 40 min of culture) (B). Kinetics of IL-1β secretion after BMDMs stimulation \u0026nbsp;(C). TNF-α measurement in the cell supernatant after 24 h of stimulation. (D). IL-1β (E) and \u0026nbsp;TNF-α (F) levels after 24 h-incubation of BMDMs with EPS in the presence of different \u0026nbsp;concentrations (0-2 μg/mL) of the phagocytosis inhibitor Cytochalasin D. Results are \u0026nbsp;expressed as mean ± SE and are representative of two to three independent experiments. **p \u0026nbsp;\u0026lt; 0.01; ***p \u0026lt; 0.001, vs. cells with only medium or between groups indicated by brackets.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/d95d9b32d4f796688f480497.png"},{"id":63848648,"identity":"396f4cc3-6c0a-4e83-8c6c-a1b1231ae6df","added_by":"auto","created_at":"2024-09-03 03:26:42","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":93318,"visible":true,"origin":"","legend":"\u003cp\u003eG. lucidum exopolysaccharides induce IL-1β production via Dectin-1/Syk/NF-kB \u0026nbsp;signaling axis. Intracellular Syk and Nfkb1 mRNA of BMDMs after 6 h stimulation with EPS \u0026nbsp;or LPS (positive control) were analyzed by RT-qPCR (A). Transgenic BWZ cells and \u0026nbsp;sublines expressing dectin-1, B3Z cells expressing dectin-2, Mincle, FcRγ chain, dectin-2 + \u0026nbsp;FcRγ, MCL (dectin-3) + FcRγ, dectin-2 + MCL + FcRγ, Mincle + FcRγ or Mincle + MCL + \u0026nbsp;FcRγ were stimulated with EPS (100 μg/mL) for 18 hours. After this period, lacZ activity \u0026nbsp;was measured in a colorimetric assay under OD 560/620 (B). Experiment carried out in \u0026nbsp;biological triplicate. ***p \u0026lt; 0.05.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/d93592137de20026197e9441.png"},{"id":63848645,"identity":"71ab1caf-3932-46f2-aba0-275a541f17cd","added_by":"auto","created_at":"2024-09-03 03:26:41","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":160360,"visible":true,"origin":"","legend":"\u003cp\u003eInflammasome activation by G. lucidum exopolysaccharide stimulus depends \u0026nbsp;primarily on caspase-1 and, to a lesser extent, caspase-8 activity. Median fluorescence \u0026nbsp;intensity (MFI) of fluorescent caspase-1-specific probe FAM-FLICA measured by flow \u0026nbsp;cytometry of BMDM stimulated with EPS (100 μg/mL) or LPS (500 ng/ml) and nigericin \u0026nbsp;(20 μM during the last 40 min of culture) for 24h (A). Quantification by ELISA of IL-1𝛽 (B \u0026nbsp;and D) and TNF-𝛼 (C and E) present in the supernatant of Wild Type (WT) or Caspase1/11- \u0026nbsp;/- BMDM stimulated with EPS (100 μg/mL) for 24h. One hour prior to stimulation, BMDMs \u0026nbsp;had caspase-1 or caspase-8 inhibitors (AC-YVAD-CHO and Z-IETD-FMK, respectively) (D \u0026nbsp;and E) added at 50 μM. Experiment carried out in biological triplicate. ***p \u0026lt; 0.05.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/bd0c5233139e5ee1793a3cf4.png"},{"id":63848649,"identity":"28be2371-83e2-4754-b727-116a05132ad7","added_by":"auto","created_at":"2024-09-03 03:26:48","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":145824,"visible":true,"origin":"","legend":"\u003cp\u003eG. lucidum exopolysaccharides activate the 572 NLRP3 inflammasome through ROS \u0026nbsp;production, potassium efflux, phagolysosomal acidification and cathepsin B release. \u0026nbsp;Intracellular Nlrp3, Aim2 and Nlrc4 mRNA of BMDMs after 6 h stimulation with EPS or \u0026nbsp;LPS (positive control) were analyzed by RT-qPCR (A). BMDMs obtained from wild-type \u0026nbsp;(WT) mice were stimulated with EPS (100 μg/mL) for 24 h (B and C). WT BMDMs were \u0026nbsp;pretreated for 1h with the indicated concentrations (Methods section) of MCC950 (B and C), \u0026nbsp;glyburide or KCl (D), DPI (E), and bafilomycin A or CA-074 (F). Then, macrophages were \u0026nbsp;stimulated with EPS for 24h. IL-1β and TNF-α levels from the cell supernatant were assessed \u0026nbsp;by ELISA (B-F). Results are expressed as mean ± SE and represent two or three independent \u0026nbsp;experiments. ***p \u0026lt; 0.001, vs. WT EPS-stimulated untreated cells.\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/875bdde561e75fb9ad7fd3af.png"},{"id":63848644,"identity":"3e233c33-2419-443e-89f3-2e0c080129af","added_by":"auto","created_at":"2024-09-03 03:26:41","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":212169,"visible":true,"origin":"","legend":"\u003cp\u003eOral treatment with G. lucidum EPS is protective in murine cryptococcosis \u0026nbsp;infection model, although it does not enhance in vitro macrophage fungicidal activity. \u0026nbsp;Quantification by ELISA of TNF-𝛼 (A) and IL-1𝛽 (B) present in the supernatant of Wild \u0026nbsp;Type (WT) or NLRP3-/- BMDM stimulated with EPS (100 μg/mL) or LPS (500ng/mL) plus \u0026nbsp;IFN-γ (50ng/mL) for 12h and later co-cultivated with opsonized C. neoformans (MOI 5:1) \u0026nbsp;for 24h. The fungicidal activity of BMDMs (C) and BMDCs (D) was determined by the \u0026nbsp;percentage of fungal killing. It is expressed as the percent reduction of CFU at 24h versus \u0026nbsp;the 2h co-cultivation time points. Results are expressed as mean ± SE and represent three \u0026nbsp;independent experiments. *p \u0026lt; 0.05; **p \u0026lt; 0.01; ***p \u0026lt; 0.001. E: C57BL/6 mice were \u0026nbsp;infected intranasally with 25uL of PBS containing 1×104 yeasts of C. neoformans H99 strain. \u0026nbsp;After three days of infection, the animals were treated three times a week by gavage or \u0026nbsp;intranasal administration of EPS (25μg delivered in 50μL of PBS) or PBS as control. ** \u0026nbsp;denotes that the survival curve of animals orally treated with EPS was significantly different \u0026nbsp;from that of the control, as assessed by the log-rank (Mantel-Cox) test (P ≤ 0.01). Data \u0026nbsp;reported are from one representative experiment out of two with comparable results.\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/98586cb134188df26de27096.png"},{"id":63849169,"identity":"a07b5172-625a-47d2-b95f-537b3998827f","added_by":"auto","created_at":"2024-09-03 03:34:48","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":1408194,"visible":true,"origin":"","legend":"\u003cp\u003eProposed signaling pathway that regulates the NLRP3 inflammasome activation \u0026nbsp;by G. lucidum extracellular polysaccharides (EPS) in macrophages. EPS primes \u0026nbsp;macrophages by a canonical Dectin-1/Syk/NF-kB signaling axis, leading to NLRP3 and pro- \u0026nbsp;IL-1β production. Next, the NLRP3-inflammasome is triggered by ROS production, potassium efflux, phagolysosome acidification and cathepsin B release, \u0026nbsp;resulting in IL-1β processing and release by caspase-1 and caspase-8 dependent cleavage.\u003c/p\u003e","description":"","filename":"8.png","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/ba2abf29cfe4418fc4aa0882.png"},{"id":66467908,"identity":"cd2dae13-c3e4-4978-a148-d4df609f8da4","added_by":"auto","created_at":"2024-10-12 14:08:54","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1437398,"visible":true,"origin":"","legend":"","description":"","filename":"Burgueletal.2024.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1_covered_6cc8593c-7537-4ef3-976e-e0a48d08ae9c.pdf"},{"id":63848643,"identity":"a60f4984-0562-4cc0-a7cc-399e333c4cc5","added_by":"auto","created_at":"2024-09-03 03:26:41","extension":"tif","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":130086,"visible":true,"origin":"","legend":"\u003cp\u003eFig. S1. Evaluation of the monosaccharide constituents of EPS extracted from \u0026nbsp;Ganoderma lucidum. The analysis was carried out using the GC-MS technique of the \u0026nbsp;monosaccharide constituents of the soluble (A) and insoluble (B) fractions of G. lucidum. \u0026nbsp;Fuc – Fucose; Xyl – Xylose; Man – Mannose; Glc – Glucose; Gal – Galactose; Rib – Ribose; \u0026nbsp;Ara – Arabinose.\u003c/p\u003e","description":"","filename":"FigureS1.tif","url":"https://assets-eu.researchsquare.com/files/rs-4751112/v1/5c21b2bc6181035c00e1d73b.tif"}],"financialInterests":"","formattedTitle":"Exopolysaccharides extracted from submerged cultures of Ganoderma lucidumactivate the NLRP3 inflammasome","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"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":"inflammasome, Ganoderma, polysaccharides, NLRP3, innate immunity","lastPublishedDoi":"10.21203/rs.3.rs-4751112/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4751112/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"Interleucin-1β (IL-1β) is a pivotal cytokine in pro-inflammatory response induction, and it is regarded as protective in various diseases. IL-1β secretion is mainly associated with activation of the inflammasome complex, which generally is tightly regulated, depending on two signals for significant activity. The water-insoluble fraction of the mushroom Ganoderma lucidum was extracted and co-cultivated with murine bone marrow macrophages. We demonstrated that G. lucidum exopolysaccharides (EPS) could induce IL-1β production and release in murine macrophages. The mechanisms underlying EPS-induced priming encompass recognition through dectin-1 and activation of the spleen tyrosine kinase (Syk) / nuclear factor kappa-light-chain-enhancer of the activated B (NF-kB) axis. In addition, EPS stimulates IL-1β secretion in a phagocytosis-dependent manner via the NLR family pyrin domain containing 3 (NLRP3) inflammasome activation in response to reactive oxygen species production, potassium efflux, phagolysosomal acidification, and cathepsin B release. Both caspase-1 and, to a lesser extent, caspase-8 were activated upon EPS stimulus and required for IL-1β cleavage and release. The treatment with EPS by gavage of Cryptococcus neoformans-infected mice showed increased survival. Our study highlighted significant stimulation by G. lucidum EPS to innate immune cells, suggesting a potential adjuvant in antimicrobial treatment schemes.","manuscriptTitle":"Exopolysaccharides extracted from submerged cultures of Ganoderma lucidumactivate the NLRP3 inflammasome","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-09-03 03:26:36","doi":"10.21203/rs.3.rs-4751112/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":"e6aa2639-a27b-4402-973e-a163f76c2f50","owner":[],"postedDate":"September 3rd, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-10-12T14:08:13+00:00","versionOfRecord":[],"versionCreatedAt":"2024-09-03 03:26:36","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-4751112","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4751112","identity":"rs-4751112","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}