Mechanisms of Autonomic Regulation of the Human Cardiovascular System in Hypomagnetic Conditions After Simulated 12-Month Isolation

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V. Popova, V. B. Rusanov, O. I. Orlov This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7046707/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 22 Dec, 2025 Read the published version in Microgravity Science and Technology → Version 1 posted 9 You are reading this latest preprint version Abstract During interplanetary flights, hypomagnetic conditions (HMC) may be one of the specific factors affecting the astronaut's body. Their combined effect with other factors of flight beyond low Earth orbit will greatly enhance the damaging effect on the body, including on the structural and functional state of the cardiovascular system (CVS). Our study was performed during a 12-month simulated isolation. It was attended by 6 healthy volunteers (2 men and 4 women). HMC (0.113 ± 0.062 µT) was modeled on -(2–4) days before the volunteers were placed in a hermetic facility and at the final stage of isolation (346–350) days of stay in a hermetic facility. Two 4-hour exposures with GMU exposure and background studies were conducted. Throughout their stay in the facility, each volunteer underwent continuous electrocardiogram (ECG) recording. The main indicators characterizing the autonomic modulating effects on the cardiovascular system changed in the HMC as follows: compared with the background, both women and men had higher heart rate in the HMC, VLF(mc 2 ) and LF(mc 2 ), as well as in men, the total power of the spectrum increased and prevailed in both exposures. When viewing ECG recordings in women, episodes of tachycardia were detected in the isolation exposure, as well as cardiac arrhythmias in the form of extrasystoles of ventricular and atrial origin, no cardiac arrhythmias were detected before isolation. In general, the strongest response of regulatory mechanisms associated with autonomic influences on the CVS in the HMC after 12 months of isolation was observed in women compared to men. cardiovascular system hypomagnetic conditions heart rate variability isolation experiment Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Introduction Geomagnetic field (GMF) is an important component of the existence of all living systems of the Earth. It forms a protective shield that protects the planet from the excessive effects of the solar wind (Erdmann et al., 2021). In addition, many animals (birds, fish, and insects) navigate in space mainly by its fluctuations (Formicki et al., 2019, Hagstrum, 2023). Geomagnetic fluctuations affect the most important physiological processes, affecting the functioning of both individual organs and entire systems (Breus et al., 2012; Hart, 2023), therefore, changes in GMF can lead to adverse consequences for living organisms. This is due to the special interest of researchers from various fields of science in studying the multifaceted aspects that determine the importance of GMF for the entire variety of living organisms, undoubtedly including Homo sapiens , living on the planet. For scientists engaged in research in the field of space biology and medicine, this is also of direct interest, since as they move away from the earth's surface, the strength of GMP decreases, and organisms find themselves in new, hypomagnetic conditions (HMC) (Zhang et al., 2021). To date, the number of publications on the effects of reduced MF in space flight (SF) on mammals and, in particular, on humans has not been sufficiently studied (Binhi V.N. et al., 2017). Over the past 10 years, Scopus/WOS has found fewer than 300 publications containing an insignificant amount of experimental data on the search for HMC and its effect on the body. People not only encounter HMC on the Ground, but also create them themselves, for example, at industrial and military facilities, in buildings and structures with thick concrete or metal walls (Sinčák, Sedlakova-Kadukova, 2023). Due to increased attention to this problem, information about the effects of HMC on organisms obtained in the course of scientific work can be used in biomedical research to improve the quality of life of the population (Taletaviciene et al., 2021). Published studies indicate a number of rearrangements occurring in the human body during prolonged exposure to HMC (Zhang et al., 2021). Functional changes are noted in the respiratory, nervous, immune, reproductive, and circulatory systems (Gurfinkel et al., 2018). The most significant transformations are manifested in the work of the central nervous system (CNS) and cardiovascular system (CVS) (Luchitskaya et al., 2024), exacerbating existing or provoking new diseases. Thus, significant changes in heart rate variability (HRV), blood pressure, heart rate (HR), melatonin levels and hormonal balance were found, which lead to a decrease in the efficiency of the functioning of the body as a whole (Breus et al., 2012; Vencloviene et al., 2017). Such rearrangements are already recorded when the strength of the GMF is less than 10 times weaker, while during deep space exploration, crew members will be exposed to a magnetic factor that is about 10,000 times weaker than Earth's (Binhi V.N. et al., 2017). In SF on board the International Space Station (ISS), the lack of such studies is primarily due to the fact that its orbit is located at a distance of about 400 km from the earth's surface, at such an altitude the strength of the GMF is slightly reduced and is close to ground values (DeVirgiliis L. et al., 2025). As a result, until recently, scientists had not set themselves the task of studying the effects of HMC on living objects. However, for example, a study by Otsuka K. et al., 2019 showed that changes in the magnetic field in the SF can affect c CVS parameters associated with slowing aging or longevity. Materials and methods Organization of research. The presented study is part of a comprehensive study of the effect of simulated GMUs on the physiological systems of the human body within the framework of the SIRIUS (Scientific International Research in Unique Terrestrial Station) project (http://sirius.imbp.ru/). This fragment will describe the results we have obtained regarding the mechanisms of vegetative regulation of the cardiovascular system. The SIRIUS project was a series of isolation experiments conducted from 2017 to 2024. It was an analog platform that simulated elements of interplanetary SF of varying duration. The SIRIUS project was carried out in a Ground-Based Experimental Facility (GBEF) located on the territory of Federal State Budgetary Institution of Science State Scientific Center of the Russian Federation – Institute of Biomedical Problems of the Russian Academy of Sciences, Moscow, Russia, which is a fully isolated hermetic facility ( Fig. 1 ) consisting of interconnected multifunctional experimental modules (50 m 3 , 100 m 3 , 150 m 3 and 250 m 3 ) equipped with autonomous life support systems (ventilation and air conditioning, water supply, sewerage, electricity and etc. Complex engineering communications made it possible to create and maintain a habitat with specified parameters, isolate the crew from the environment for a specified time of isolation and simulate some main factors of a real SF, with the exception of weightlessness and radiation exposure. Therefore, the GBEF was a testing ground for any technologies being developed for use in future real missions beyond low Earth orbit (LEO) (Agaptseva T.N. et al., 2024; Shelhamer M. et al., 2020). During the preparation phase, the experimental complex was equipped with first aid equipment and medical monitoring equipment. Medical care was one of the main safety conditions during isolation, as it allowed timely organization of measures to preserve the health of the volunteers involved (Fedyay, S. et al., 2023). In addition, the implementation of similar projects related to isolation and restriction contributed to the optimization of the medical support program for manned SF and other small groups in extreme conditions. Our study was performed during a 12-month simulated isolation. It involved 6 healthy volunteers (2 men and 4 women (all studies were conducted in the luteal phase of the cycle - 17-27 days of the menstrual cycle)). The age ranged from 25 to 37 years, with a body mass index of 22.13±0.57 kg/m 2 for men and 20.25±1.4 kg/m 2 for women. All the volunteers received admission from the Medical Expert Commission SSC RF – IMBP RAS. The conducted studies were approved by the SSC RF – IMBP RAS Bioethics Commission (Protocol No. 643 dated 07.07.2023). The volunteers were in the GBEF, in isolated conditions, for 366 days. The scenario implemented in the 12-month mission included a "flight" to the lunar orbital station, a "landing" on the moon and a "return" to Earth. HMC were modeled on (2-4) days before the volunteers were placed in a hermetic facility ( Exp1 ) and at the final stage of isolation (346-350 days of stay in a hermetic facility, Exp2 ). The cyclogram of the study is presented below ( Fig. 2 ). For each volunteer, two exposures of 4 hours each were performed with HMC exposure in the Magnetic field modeling system, the ARFA installation ( Fig. 3 ) (Kukanov V. Yu. et al., 2023). The average values of the magnetic field during the session were 0.113±0.062 µT. Signal recording and analysis. Throughout their stay in the facility, each volunteer underwent continuous electrocardiogram (ECG) recording. For registration, the Varicard 2.8 hardware and software complex (RAMENA LLC, Ryazan, Russia) was used with a sampling frequency of 1000 Hz per channel, which gave a time resolution of 1 ms. The received signal was edited using visual verification and manual correction of individual RR intervals and classification of QRS complexes. Abnormal complexes not caused by depolarization of the sinoatrial (SA) node were excluded from the recording. The recording was saved for subsequent offline processing. The construction and processing of cardiointervalograms and analysis of HRV was carried out using the ISKIM-6 software (Ramena LLC, Ryazan, Russia). HRV analysis was chosen as a tool for assessing the mechanisms of autonomic regulation, since it is the final process that ensures homeostasis at the vegetative level of the body, and is a complex biomarker reflecting complex relationships both in the circulatory system and in the whole organism (Thayer J.F. et al., 2009). In addition, HRV can characterize the level of functional state, as well as individual mechanisms that carry out internal adjustments by changing the systemic interaction of the internal and external environment (Holzman J.B. et al., 2017), i.e. adaptivity of the organism (Beckers F, et al., 2009). The following HRV indicators were evaluated: HR (bpm.) ̶ heart rate; pNN50 (%) − the number of pairs of cardiac intervals with a difference of more than 50 ms. in % of the total number of cardiointervals, the relative degree of predominance of the parasympathetic link of regulation over the sympathetic; TP (ms 2 ) – the total power of the HRV spectrum. The total activity level of the various links of the regulatory mechanism; HF (ms 2 ) – the power of high frequency fluctuations with a frequency of 0.15-0.4 Hz and a period of 2.5 to 7 s. Relative activity level of the parasympathetic regulatory link; LF (ms 2 ) – the power of low-frequency heart rate fluctuations with a frequency in the range of 0.04-0.15 Hz and with a period of 7 to 25 seconds; VLF (ms 2 ) – very low frequency, fluctuations with a frequency of 0.003-0.05 Hz and an oscillation period of 25 to 70 s; IC – the degree of centralization of heart rate control, the predominance of activity of the central circuit of regulation over the autonomous one, (LF+VLF)/HF; Narr, % – total number of arrhythmias. Statistical processing. Statistical processing was carried out in the PRISMA 8 program. According to the Jarque–Bera test, the majority of the studied sample distributions did not meet the criteria of normality, therefore, a ranked, quantitative nonparametric Mann–Whitney criterion was applied when analyzing the data. Results The main indicators characterizing the vegetative modulating effects on the cardiovascular system changed in the HMC as follows. Compared to the background, both women and men had higher heart rate with a decrease in GMF (p<0.05). The opposite dynamics was observed with pNN50 (%) ( Fig. 4 ), an indicator that directly reflects the processes of autonomic regulation and the state of vagosympathetic balance, determined by parasympathetic modulating effects on the SA node. A decrease in its values (p<0.05) may indicate instability of parasympathetic activity during stay at HMC. Initially, before being placed in a hermetic object, the low-frequency component (LF, mc 2 ) dominated in the spectral analysis of the male heart rate in the total power of the spectrum (TP, mc 2 ). Its predominance was also noted in the conditions of HMC. At the same time, an increase in VLF mc 2 and a sharp decrease in the high-frequency component of the spectrum (HF, mc 2 ) were observed during both exposures. Before the start of isolation, the high-frequency component of the spectrum prevailed in women, the severity of which decreased during their stay at the HMC. The VLF(ms 2 ) and LF(ms 2 ) values increased in both exposures as well as in men and dominated the total power of the spectrum ( Fig. 5 ). The degree of centralization of heart rhythm control ( Fig. 6 ) was higher ( p<0.05 ) than the values recorded before isolation in both exposures. This may indicate suboptimal regulation, imperfection or insufficiency of autonomic regulation in the HMC and the need for "intervention" in the activity of the autonomic nervous system (autonomous level of regulation) to correct regulatory processes modulating the activity of the SA node of the structures of the central nervous system, humoral and metabolic regulatory mechanisms. Discussion Some common risk factors for cardiovascular disease seem to affect men and women equally (for example, high blood pressure and cholesterol levels), while others seem to be more associated with an increased risk of cardiovascular disease in women than in men (for example, diabetes and smoking) (Appelman Y, et al., 2015 ). In addition to physiological changes, psychosocial factors in middle age can affect the health of the cardiovascular system of women and men directly through biopsychosocial mechanisms, as well as through the influence on their health-related behavior (Stewart A.L., et al., 2018). Reduced GMF, apparently, can modify the effect of risk factors and be a trigger for the development of cardiovascular events. Normal levels of GMF ensure the healthy functioning of many physiological systems of the body, and fluctuations and periodicity of geomagnetic variations can set the rhythms of the functioning of individual human body systems with their synchronization in the short-term (circadian) interval. In the case of removal from the LEO, the effect of GMF variations on the body decreases due to a decrease in its level. This increases the risk of desynchronization of the internal rhythms of the body's functional systems, primarily the cardiovascular system. Studying the female body is quite difficult, since the hormonal background of women depends on the menstrual cycle. Thus, according to some authors (Matsumoto T., et al., 2007 ; Tousignant-Lafl amme Y., et al., 2009), HRV, and therefore the effectiveness of adrenergic and cholinergic effects on the heart rate during menstrual cycle, does not change, according to others (Leicht A., et al., 2003) — HRV decreases (i.e., the effectiveness of activating adrenergic effects on the heart rate increases) during ovulation and increases (i.e. the activity of adrenergic effects decreases) in the luteal phase of the cycle (Bai X., et al., 2009 ; Sato N., et al., 2004). Since the total power of the spectrum at the final stage of isolation, compared with the initial values, was dominated by the low-frequency HRV component when volunteers were placed in the HMC, this may indicate hyper activation of sympathetic activity, which in turn is a factor in the development of cardiovascular events (Li L., et al., 2021 , Christensen N.J., et al., 2007 ). In this regard, it was decided to analyze the Narr indicator (%), which characterizes the total number of arrhythmias (Fig. 7 ). The results of the analysis showed that during the women's stay at HMC(p < 0.05), this indicator increased co-directionally with the predominance of the low-frequency component in the total spectrum power. When viewing ECG recordings, episodes of tachycardia were detected in women, as well as cardiac arrhythmias in the form of extrasystoles of ventricular and atrial origin. No cardiac arrhythmias were found in the ECG recordings made before isolation at the HMC. It is worth noting that in our previously published results of an experiment with HMC modeling involving men, when registering a daily ECG recording in HMC, cardiac arrhythmias were also detected at night (Popova O., et al., 2024). However, they were recorded when staying for more than 8 hours in a reduced GMF by 1000 times (approximately 0.048 µT). In the same study, we noted a decrease in HRV indicators characterizing the parasympathetic component of the regulation link. Conclusion In general, in HMC, after being isolated for 12 months with constant environmental conditions in a closed hermetic facility, we identified the most reactive reaction of regulatory mechanisms associated with vegetative influences on the cardiovascular system, in particular, on the SA node in women compared with men. However, it is necessary to note the limitations associated with our study. First of all, this is too small a sample and the number of men and women who were isolated is not the same. At the same time, this situation is related to the specifics of the organization of the isolation experiment and the technical capabilities of the GBEF. At the same time, it should be noted that a deeper study of the effects of HMC on the human body will contribute to the development of new technologies for long-range flights that will allow space expeditions to the Moon and, in the future, to Mars, preventing organ system malfunctions and the development of pathologies in astronauts and astronauts (Zeitlin et al., 2013 ; Robertson et al. al., 2020). Declarations Author Contributions O.P. developed the concept, performed the research, interpreted, analyzed, and visualized the collected data, performed the statistical analysis, and prepared the manuscript. V.R. participated in the concept development, edited the manuscript, and contributed to the resources for the study. O.O. developed the concept, contributed to the resources for the study, and edited the manuscript. All authors read and approved the final manuscript. Funding The work was carried out within the framework of the fundamental research programs of the Institute of Biomedical Problems of the Russian Academy of Sciences [FMFR-2024-0042]. Data Availability No datasets were generated or analysed during the current study. Declarations Ethical Approval The experimental program was approved by the Bioethics Commission of the Institute of Biomedical Problems of the Russian Academy of Sciences, (Russian Federation, Moscow) (Protocol No. 643 dated July 7, 2023) and fully complied with the principles of the 1964 Helsinki Declaration of Human Rights. Each participant signed a voluntary informed consent after being explained the potential risks, benefits and nature of the experiment, as well as the specifics of the included studies. Consent to Participate Informed consent was obtained from all individual participants included in the study. Consent for Publication Patients signed informed consent regarding publishing their data. 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Cite Share Download PDF Status: Published Journal Publication published 22 Dec, 2025 Read the published version in Microgravity Science and Technology → Version 1 posted Editorial decision: Revision requested 11 Aug, 2025 Reviews received at journal 24 Jul, 2025 Reviews received at journal 22 Jul, 2025 Reviewers agreed at journal 13 Jul, 2025 Reviewers agreed at journal 11 Jul, 2025 Reviewers invited by journal 11 Jul, 2025 Editor assigned by journal 09 Jul, 2025 Submission checks completed at journal 09 Jul, 2025 First submitted to journal 04 Jul, 2025 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. 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Orlov","email":"","orcid":"","institution":"Federal State Budgetary Institution of Science State Scientific Center of the Russian Federation – Institute of Biomedical Problems of the Russian Academy of Sciences (SSC RF - IMBP RAS)","correspondingAuthor":false,"prefix":"","firstName":"O.","middleName":"I.","lastName":"Orlov","suffix":""}],"badges":[],"createdAt":"2025-07-04 12:23:16","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7046707/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7046707/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s12217-025-10209-0","type":"published","date":"2025-12-22T15:58:07+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":86767942,"identity":"c6004bed-7840-44c2-87b1-07852cb71863","added_by":"auto","created_at":"2025-07-15 11:21:58","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":104986,"visible":true,"origin":"","legend":"\u003cp\u003eGround-Based Experimental Facility\u003c/p\u003e","description":"","filename":"Fig1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7046707/v1/1f129505e81762ed57ac8e02.jpg"},{"id":86767943,"identity":"52aa744e-0bee-43d9-ac4d-435e1716f0cc","added_by":"auto","created_at":"2025-07-15 11:21:58","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":45507,"visible":true,"origin":"","legend":"\u003cp\u003eCyclogram\u003c/p\u003e","description":"","filename":"Fig2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7046707/v1/3db176177099577dc8bdb8de.jpg"},{"id":86771033,"identity":"dfd99f86-ae96-42f2-b8d1-435077103725","added_by":"auto","created_at":"2025-07-15 11:45:58","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":150919,"visible":true,"origin":"","legend":"\u003cp\u003eInstallationof \" ARFA \". A - General view. B is the layout of the tester inthe \" ARFA \". (1) – the exposure unit, (2) – an armchair.\u003c/p\u003e","description":"","filename":"Fig3.png","url":"https://assets-eu.researchsquare.com/files/rs-7046707/v1/63a3d669b66cc0caeb470088.png"},{"id":86767947,"identity":"7965dcf3-cff6-4030-b3d5-374e19b36baf","added_by":"auto","created_at":"2025-07-15 11:21:58","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":18247,"visible":true,"origin":"","legend":"\u003cp\u003eDynamics of heart rate and indicator that reflectthe processes of vegetative regulation and the state of vagosympathetic balance, *- \u003cem\u003ep\u0026lt;0.05\u003c/em\u003e\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7046707/v1/81c07ef86a81ac2c6f6506e1.png"},{"id":86769946,"identity":"fb6503b4-baa2-4663-a967-3d65c4ec7bb7","added_by":"auto","created_at":"2025-07-15 11:37:58","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":71991,"visible":true,"origin":"","legend":"\u003cp\u003eHRV spectral indexes\u003c/p\u003e","description":"","filename":"Fig5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-7046707/v1/21a7c2a59801fc998959668d.jpg"},{"id":86768729,"identity":"e25b1442-48d9-457f-8c03-61f1288176bc","added_by":"auto","created_at":"2025-07-15 11:29:58","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":11661,"visible":true,"origin":"","legend":"\u003cp\u003eThe degree of centralization of heart rhythm control (IC),*- p\u0026lt;0.05\u003c/p\u003e","description":"","filename":"6.png","url":"https://assets-eu.researchsquare.com/files/rs-7046707/v1/3ff85edf698b24219180f0ca.png"},{"id":86769948,"identity":"ba93d5ce-78ea-4822-a438-f9fba722a4dd","added_by":"auto","created_at":"2025-07-15 11:37:58","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":10001,"visible":true,"origin":"","legend":"\u003cp\u003eNarr(%), *- p\u0026lt;0.05\u003c/p\u003e","description":"","filename":"7.png","url":"https://assets-eu.researchsquare.com/files/rs-7046707/v1/a2fa3569c008fc1f23816689.png"},{"id":99172465,"identity":"d29d8d1d-902e-4941-8b14-f84bf3c757a6","added_by":"auto","created_at":"2025-12-29 16:09:54","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":897794,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7046707/v1/0556ad94-c075-41f3-bf56-0a30c35a0d3d.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eMechanisms of Autonomic Regulation of the Human Cardiovascular System in Hypomagnetic Conditions After Simulated 12-Month Isolation\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eGeomagnetic field (GMF) is an important component of the existence of all living systems of the Earth. It forms a protective shield that protects the planet from the excessive effects of the solar wind (Erdmann et al., 2021). In addition, many animals (birds, fish, and insects) navigate in space mainly by its fluctuations (Formicki et al., 2019, Hagstrum, 2023).\u003c/p\u003e\n\u003cp\u003eGeomagnetic\u0026nbsp;fluctuations affect the most important physiological processes, affecting the functioning of both individual organs and entire systems (Breus et al., 2012; Hart, 2023), therefore, changes in GMF can lead to adverse consequences for living organisms.\u003c/p\u003e\n\u003cp\u003eThis\u0026nbsp;is due to the special interest of researchers from various fields of science in studying the multifaceted aspects that determine the importance of GMF for the entire variety of living organisms, undoubtedly including \u003cem\u003eHomo\u003c/em\u003e\u003cem\u003e\u0026nbsp;sapiens\u003c/em\u003e, living on the planet. For scientists engaged in research in the field of space biology and medicine, this is also of direct interest, since as they move away from the earth\u0026apos;s surface, the strength of GMP decreases, and organisms find themselves in new, hypomagnetic conditions (HMC) (Zhang et al., 2021).\u003c/p\u003e\n\u003cp\u003eTo\u0026nbsp;date, the number of publications on the effects of reduced MF in space flight (SF) on mammals and, in particular, on humans has not been sufficiently studied (Binhi V.N. et al., 2017). Over the past 10 years, Scopus/WOS has found fewer than 300 publications containing an insignificant amount of experimental data on the search for HMC and its effect on the body.\u003c/p\u003e\n\u003cp\u003ePeople not only encounter HMC on the Ground, but also create them themselves, for example, at industrial and military facilities, in buildings and structures with thick concrete or metal walls (Sinč\u0026aacute;k, Sedlakova-Kadukova, 2023). Due to increased attention to this problem, information about the effects of HMC on organisms obtained in the course of scientific work can be used in biomedical research to improve the quality of life of the population (Taletaviciene et al., 2021).\u003c/p\u003e\n\u003cp\u003ePublished\u0026nbsp;studies indicate a number of rearrangements occurring in the human body during prolonged exposure to HMC (Zhang et al., 2021).\u003c/p\u003e\n\u003cp\u003eFunctional\u0026nbsp;changes are noted in the respiratory, nervous, immune, reproductive, and circulatory systems (Gurfinkel et al., 2018). The most significant transformations are manifested in the work of the central nervous system (CNS) and cardiovascular system (CVS) (Luchitskaya et al., 2024), exacerbating existing or provoking new diseases. Thus, significant changes in heart rate variability (HRV), blood pressure, heart rate (HR), melatonin levels and hormonal balance were found, which lead to a decrease in the efficiency of the functioning of the body as a whole (Breus et al., 2012; Vencloviene et al., 2017).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSuch\u0026nbsp;rearrangements are already recorded when the strength of the GMF is less than 10 times weaker, while during deep space exploration, crew members will be exposed to a magnetic factor that is about 10,000 times weaker than Earth\u0026apos;s (Binhi V.N. et al., 2017).\u003c/p\u003e\n\u003cp\u003eIn SF on board the International Space Station (ISS), the lack of such studies is primarily due to the fact that its orbit is located at a distance of about 400 km from the earth\u0026apos;s surface, at such an altitude the strength of the GMF is slightly reduced and is close to ground values (DeVirgiliis L. et al., 2025). As a result, until recently, scientists had not set themselves the task of studying the effects of HMC on living objects. However, for example, a study by Otsuka K. et al., 2019 showed that changes in the magnetic field in the SF can affect c CVS parameters associated with slowing aging or longevity.\u003c/p\u003e"},{"header":"Materials and methods ","content":"\u003cp\u003e\u003cem\u003eOrganization\u003c/em\u003e\u003cem\u003e\u0026nbsp;of research.\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe presented study is part of a comprehensive study of the effect of simulated GMUs on the physiological systems of the human body within the framework of the SIRIUS (Scientific International Research in Unique Terrestrial Station) project (http://sirius.imbp.ru/). This fragment will describe the results we have obtained regarding the mechanisms of vegetative regulation of the cardiovascular system.\u003c/p\u003e\n\u003cp\u003eThe SIRIUS project was a series of isolation experiments conducted from 2017 to 2024. It was an analog platform that simulated elements of interplanetary SF of varying duration.\u003c/p\u003e\n\u003cp\u003eThe SIRIUS project was carried out in a Ground-Based Experimental Facility (GBEF) located on the territory of\u0026nbsp;Federal\u0026nbsp;State Budgetary Institution of Science State Scientific Center of the Russian Federation \u0026ndash; Institute of Biomedical Problems of the Russian Academy of Sciences,\u0026nbsp;Moscow, Russia, which is a fully isolated hermetic facility (\u003cstrong\u003eFig.\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;1\u003c/strong\u003e) consisting of interconnected multifunctional experimental modules (50 m\u003csup\u003e3\u003c/sup\u003e, 100 m\u003csup\u003e3\u003c/sup\u003e, 150 m\u003csup\u003e3\u003c/sup\u003e and 250 m\u003csup\u003e3\u003c/sup\u003e) equipped with autonomous life support systems (ventilation and air conditioning, water supply, sewerage, electricity and etc. Complex engineering communications made it possible to create and maintain a habitat with specified parameters, isolate the crew from the environment for a specified time of isolation and simulate some main factors of a real SF, with the exception of weightlessness and radiation exposure. Therefore, the GBEF was a testing ground for any technologies being developed for use in future real missions beyond low Earth orbit (LEO) (Agaptseva T.N. et al., 2024; Shelhamer M. et\u0026nbsp;al.,\u0026nbsp;2020).\u003c/p\u003e\n\u003cp\u003eDuring the preparation phase, the experimental complex was equipped with first aid equipment and medical monitoring equipment. Medical care was one of the main safety conditions during isolation, as it allowed timely organization of measures to preserve the health of the volunteers involved (Fedyay, S. et al., 2023). In addition, the implementation of similar projects related to isolation and restriction contributed to the optimization of the medical support program for manned SF and other small groups in extreme conditions.\u003c/p\u003e\n\u003cp\u003eOur\u0026nbsp;study was performed during a 12-month simulated isolation. It involved 6 healthy volunteers (2 men and 4 women (all studies were conducted in the luteal phase of the cycle - 17-27 days of the menstrual cycle)). The age ranged from 25 to 37 years, with a body mass index of 22.13\u0026plusmn;0.57 kg/m\u003csup\u003e2\u003c/sup\u003e\u003csup\u003e\u0026nbsp;\u003c/sup\u003efor men and 20.25\u0026plusmn;1.4 kg/m\u003csup\u003e2\u003c/sup\u003e for women.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll\u0026nbsp;the volunteers received admission from the Medical Expert Commission SSC RF \u0026ndash; IMBP RAS. The conducted studies were approved by the SSC RF \u0026ndash; IMBP RAS Bioethics Commission (Protocol No. 643 dated 07.07.2023). The volunteers were in the GBEF, in isolated conditions, for 366 days. The scenario implemented in the 12-month mission included a \u0026quot;flight\u0026quot; to the lunar orbital station, a \u0026quot;landing\u0026quot; on the moon and a \u0026quot;return\u0026quot; to Earth. HMC were modeled on (2-4) days before the volunteers were placed in a hermetic facility (\u003cstrong\u003eExp1\u003c/strong\u003e) and at the final stage of isolation (346-350 days of stay in a hermetic facility, \u003cstrong\u003eExp2\u003c/strong\u003e). The cyclogram of the study is presented below (\u003cstrong\u003eFig.\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;2\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eFor\u0026nbsp;each volunteer, two exposures of 4 hours each were performed with HMC exposure in the Magnetic field modeling system, the ARFA installation (\u003cstrong\u003eFig.\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;3\u003c/strong\u003e) (Kukanov V. Yu. et al., 2023). The average values of the magnetic field during the session were 0.113\u0026plusmn;0.062 \u0026micro;T.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSignal\u003c/em\u003e\u003cem\u003e\u0026nbsp;recording and analysis.\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThroughout\u0026nbsp;their stay in the facility, each volunteer underwent continuous electrocardiogram (ECG) recording. For registration, the Varicard 2.8 hardware and software complex (RAMENA LLC, Ryazan, Russia) was used with a sampling frequency of 1000 Hz per channel, which gave a time resolution of 1 ms. The received signal was edited using visual verification and manual correction of individual RR intervals and classification of QRS complexes. Abnormal complexes not caused by depolarization of the sinoatrial (SA) node were excluded from the recording. The recording was saved for subsequent offline processing.\u003c/p\u003e\n\u003cp\u003eThe construction and processing of cardiointervalograms and analysis of HRV was carried out using the ISKIM-6 software (Ramena LLC, Ryazan, Russia).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eHRV\u0026nbsp;analysis was chosen as a tool for assessing the mechanisms of autonomic regulation, since it is the final process that ensures homeostasis at the vegetative level of the body, and is a complex biomarker reflecting complex relationships both in the circulatory system and in the whole organism (Thayer J.F. et al., 2009). In addition, HRV can characterize the level of functional state, as well as individual mechanisms that carry out internal adjustments by changing the systemic interaction of the internal and external environment (Holzman J.B. et al., 2017), i.e. adaptivity of the organism (Beckers F, et al., 2009).\u003c/p\u003e\n\u003cp\u003eThe following HRV indicators were evaluated:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eHR\u0026nbsp;(bpm.) ̶ heart rate;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003epNN50 (%)\u0026nbsp;\u0026minus; the number of pairs of cardiac intervals with a difference of more than 50 ms. in % of the total number of cardiointervals, the relative degree of predominance of the parasympathetic link of regulation over the sympathetic;\u003c/p\u003e\n\u003cp\u003eTP (ms\u003csup\u003e2\u003c/sup\u003e) \u0026ndash; the total power of the HRV spectrum. The total activity level of the various links of the regulatory mechanism;\u003c/p\u003e\n\u003cp\u003eHF (ms\u003csup\u003e2\u003c/sup\u003e) \u0026ndash; the power of high frequency fluctuations with a frequency of 0.15-0.4 Hz and a period of 2.5 to 7 s. Relative activity level of the parasympathetic regulatory link;\u003c/p\u003e\n\u003cp\u003eLF (ms\u003csup\u003e2\u003c/sup\u003e) \u0026ndash; the power of low-frequency heart rate fluctuations with a frequency in the range of 0.04-0.15 Hz and with a period of 7 to 25 seconds;\u003c/p\u003e\n\u003cp\u003eVLF (ms\u003csup\u003e2\u003c/sup\u003e) \u0026ndash; very low frequency, fluctuations with a frequency of 0.003-0.05 Hz and an oscillation period of 25 to 70 s;\u003c/p\u003e\n\u003cp\u003eIC \u0026ndash; the degree of centralization of heart rate control, the predominance of activity of the central circuit of regulation over the autonomous one, (LF+VLF)/HF;\u003c/p\u003e\n\u003cp\u003eNarr, % \u0026ndash; total number of arrhythmias.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eStatistical\u003c/em\u003e\u003cem\u003e\u0026nbsp;processing.\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eStatistical processing was carried out in the PRISMA 8 program. According to the Jarque\u0026ndash;Bera test, the majority of the studied sample distributions did not meet the criteria of normality, therefore, a ranked, quantitative nonparametric Mann\u0026ndash;Whitney criterion was applied when analyzing the data.\u003c/p\u003e"},{"header":"Results ","content":"\u003cp\u003eThe main indicators characterizing the vegetative modulating effects on the cardiovascular system changed in the\u0026nbsp;HMC\u0026nbsp;as follows. Compared to the background, both women and men had higher heart rate with a decrease in GMF (p\u0026lt;0.05). The opposite dynamics was observed with pNN50 (%) (\u003cstrong\u003eFig.\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;4\u003c/strong\u003e), an indicator that directly reflects the processes of autonomic regulation and the state of vagosympathetic balance, determined by parasympathetic modulating effects on the SA node. A decrease in its values (p\u0026lt;0.05) may indicate instability of parasympathetic activity during stay at HMC.\u003c/p\u003e\n\u003cp\u003eInitially,\u0026nbsp;before being placed in a hermetic object, the low-frequency component (LF, mc\u003csup\u003e2\u003c/sup\u003e) dominated in the spectral analysis of the male heart rate in the total power of the spectrum (TP, mc\u003csup\u003e2\u003c/sup\u003e). Its predominance was also noted in the conditions of HMC. At the same time, an increase in VLF mc\u003csup\u003e2\u003c/sup\u003e and a sharp decrease in the high-frequency component of the spectrum (HF, mc\u003csup\u003e2\u003c/sup\u003e) were observed during both exposures.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eBefore\u0026nbsp;the start of isolation, the high-frequency component of the spectrum prevailed in women, the severity of which decreased during their stay at the HMC. The VLF(ms\u003csup\u003e2\u003c/sup\u003e) and LF(ms\u003csup\u003e2\u003c/sup\u003e) values increased in both exposures as well as in men and dominated the total power of the spectrum (\u003cstrong\u003eFig.\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;5\u003c/strong\u003e).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe degree of centralization of heart rhythm control (\u003cstrong\u003eFig.\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;6\u003c/strong\u003e) was higher (\u003cem\u003ep\u0026lt;0.05\u003c/em\u003e) than the values recorded before isolation in both exposures. This may indicate suboptimal regulation, imperfection or insufficiency of autonomic regulation in the HMC and the need for \u0026quot;intervention\u0026quot; in the activity of the autonomic nervous system (autonomous level of regulation) to correct regulatory processes modulating the activity of the SA node of the structures of the central nervous system, humoral and metabolic regulatory mechanisms.\u0026nbsp;\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eSome common risk factors for cardiovascular disease seem to affect men and women equally (for example, high blood pressure and cholesterol levels), while others seem to be more associated with an increased risk of cardiovascular disease in women than in men (for example, diabetes and smoking) (Appelman Y, et al., \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). In addition to physiological changes, psychosocial factors in middle age can affect the health of the cardiovascular system of women and men directly through biopsychosocial mechanisms, as well as through the influence on their health-related behavior (Stewart A.L., et al., 2018). Reduced GMF, apparently, can modify the effect of risk factors and be a trigger for the development of cardiovascular events.\u003c/p\u003e\u003cp\u003eNormal levels of GMF ensure the healthy functioning of many physiological systems of the body, and fluctuations and periodicity of geomagnetic variations can set the rhythms of the functioning of individual human body systems with their synchronization in the short-term (circadian) interval. In the case of removal from the LEO, the effect of GMF variations on the body decreases due to a decrease in its level. This increases the risk of desynchronization of the internal rhythms of the body's functional systems, primarily the cardiovascular system.\u003c/p\u003e\u003cp\u003eStudying the female body is quite difficult, since the hormonal background of women depends on the menstrual cycle. Thus, according to some authors (Matsumoto T., et al., \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2007\u003c/span\u003e; Tousignant-Lafl amme Y., et al., 2009), HRV, and therefore the effectiveness of adrenergic and cholinergic effects on the heart rate during menstrual cycle, does not change, according to others (Leicht A., et al., 2003) \u0026mdash; HRV decreases (i.e., the effectiveness of activating adrenergic effects on the heart rate increases) during ovulation and increases (i.e. the activity of adrenergic effects decreases) in the luteal phase of the cycle (Bai X., et al., \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2009\u003c/span\u003e; Sato N., et al., 2004).\u003c/p\u003e\u003cp\u003eSince the total power of the spectrum at the final stage of isolation, compared with the initial values, was dominated by the low-frequency HRV component when volunteers were placed in the HMC, this may indicate hyper activation of sympathetic activity, which in turn is a factor in the development of cardiovascular events (Li L., et al., \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e2021\u003c/span\u003e, Christensen N.J., et al., \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). In this regard, it was decided to analyze the Narr indicator (%), which characterizes the total number of arrhythmias (Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). The results of the analysis showed that during the women's stay at HMC(p\u0026thinsp;\u0026lt;\u0026thinsp;0.05), this indicator increased co-directionally with the predominance of the low-frequency component in the total spectrum power.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eWhen viewing ECG recordings, episodes of tachycardia were detected in women, as well as cardiac arrhythmias in the form of extrasystoles of ventricular and atrial origin. No cardiac arrhythmias were found in the ECG recordings made before isolation at the HMC.\u003c/p\u003e\u003cp\u003eIt is worth noting that in our previously published results of an experiment with HMC modeling involving men, when registering a daily ECG recording in HMC, cardiac arrhythmias were also detected at night (Popova O., et al., 2024). However, they were recorded when staying for more than 8 hours in a reduced GMF by 1000 times (approximately 0.048 \u0026micro;T). In the same study, we noted a decrease in HRV indicators characterizing the parasympathetic component of the regulation link.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn general, in HMC, after being isolated for 12 months with constant environmental conditions in a closed hermetic facility, we identified the most reactive reaction of regulatory mechanisms associated with vegetative influences on the cardiovascular system, in particular, on the SA node in women compared with men.\u003c/p\u003e\u003cp\u003eHowever, it is necessary to note the limitations associated with our study. First of all, this is too small a sample and the number of men and women who were isolated is not the same. At the same time, this situation is related to the specifics of the organization of the isolation experiment and the technical capabilities of the GBEF.\u003c/p\u003e\u003cp\u003eAt the same time, it should be noted that a deeper study of the effects of HMC on the human body will contribute to the development of new technologies for long-range flights that will allow space expeditions to the Moon and, in the future, to Mars, preventing organ system malfunctions and the development of pathologies in astronauts and astronauts (Zeitlin et al., \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e2013\u003c/span\u003e; Robertson et al. al., 2020).\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor Contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eO.P. developed the concept, performed the research, interpreted, analyzed, and visualized the collected data, performed the statistical analysis, and prepared the manuscript. V.R. participated in the concept development, edited the manuscript, and contributed to the resources for the study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eO.O. developed the concept, contributed to the resources for the study, and edited the manuscript. All authors read and approved the final manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe work was carried out within the framework of the fundamental research programs of the Institute of Biomedical Problems of the Russian Academy of Sciences [FMFR-2024-0042].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eData Availability\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eNo datasets were generated or analysed during the current study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eDeclarations Ethical Approval\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe experimental program was approved by the Bioethics Commission of the Institute of Biomedical Problems of the Russian Academy of Sciences, (Russian Federation, Moscow) (Protocol No. 643 dated July 7, 2023) and fully complied with the principles of the 1964 Helsinki Declaration of Human Rights. Each participant signed a voluntary informed consent after being explained the potential risks, benefits and nature of the experiment, as well as the specifics of the included studies.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConsent to Participate\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;Informed consent was obtained from all individual participants included in the study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eConsent for Publication\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003ePatients signed informed consent regarding publishing their data.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCompeting Interests\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAgaptseva T.N., Kussmaul A.R., Belakovskiy M.S. \u003cem\u003eet al.\u003c/em\u003e Analog isolation projects: An opportunity for bench-testing technologies and products designed for long-distance space missions //\u003cem\u003eJournal of Space Safety Engineering\u003c/em\u003e. \u003cstrong\u003e2024.\u003c/strong\u003e P.291-294. 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DOI:10.1002/bem.22360\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"microgravity-science-and-technology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mgst","sideBox":"Learn more about [Microgravity Science and Technology](http://link.springer.com/journal/12215)","snPcode":"12217","submissionUrl":"https://submission.nature.com/new-submission/12217/3","title":"Microgravity Science and Technology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"cardiovascular system, hypomagnetic conditions, heart rate variability, isolation experiment","lastPublishedDoi":"10.21203/rs.3.rs-7046707/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7046707/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eDuring interplanetary flights, hypomagnetic conditions (HMC) may be one of the specific factors affecting the astronaut's body. Their combined effect with other factors of flight beyond low Earth orbit will greatly enhance the damaging effect on the body, including on the structural and functional state of the cardiovascular system (CVS). Our study was performed during a 12-month simulated isolation. It was attended by 6 healthy volunteers (2 men and 4 women). HMC (0.113\u0026thinsp;\u0026plusmn;\u0026thinsp;0.062 \u0026micro;T) was modeled on -(2\u0026ndash;4) days before the volunteers were placed in a hermetic facility and at the final stage of isolation (346\u0026ndash;350) days of stay in a hermetic facility. Two 4-hour exposures with GMU exposure and background studies were conducted. Throughout their stay in the facility, each volunteer underwent continuous electrocardiogram (ECG) recording. The main indicators characterizing the autonomic modulating effects on the cardiovascular system changed in the HMC as follows: compared with the background, both women and men had higher heart rate in the HMC, VLF(mc\u003csup\u003e2\u003c/sup\u003e) and LF(mc\u003csup\u003e2\u003c/sup\u003e), as well as in men, the total power of the spectrum increased and prevailed in both exposures. When viewing ECG recordings in women, episodes of tachycardia were detected in the isolation exposure, as well as cardiac arrhythmias in the form of extrasystoles of ventricular and atrial origin, no cardiac arrhythmias were detected before isolation.\u003c/p\u003e\u003cp\u003eIn general, the strongest response of regulatory mechanisms associated with autonomic influences on the CVS in the HMC after 12 months of isolation was observed in women compared to men.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e","manuscriptTitle":"Mechanisms of Autonomic Regulation of the Human Cardiovascular System in Hypomagnetic Conditions After Simulated 12-Month Isolation","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-07-15 11:21:53","doi":"10.21203/rs.3.rs-7046707/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-08-11T08:46:57+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-24T12:47:59+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-07-22T19:14:08+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"186042960439349110696080300255407345015","date":"2025-07-13T18:51:05+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"297398277362666953456989664097542672104","date":"2025-07-11T10:50:00+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-07-11T09:53:45+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-07-09T05:18:42+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-07-09T05:18:35+00:00","index":"","fulltext":""},{"type":"submitted","content":"Microgravity Science and Technology","date":"2025-07-04T12:11:57+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"microgravity-science-and-technology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"mgst","sideBox":"Learn more about [Microgravity Science and Technology](http://link.springer.com/journal/12215)","snPcode":"12217","submissionUrl":"https://submission.nature.com/new-submission/12217/3","title":"Microgravity Science and Technology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"70218009-7e4c-42de-a0c2-3add6f187119","owner":[],"postedDate":"July 15th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-29T16:05:41+00:00","versionOfRecord":{"articleIdentity":"rs-7046707","link":"https://doi.org/10.1007/s12217-025-10209-0","journal":{"identity":"microgravity-science-and-technology","isVorOnly":false,"title":"Microgravity Science and Technology"},"publishedOn":"2025-12-22 15:58:07","publishedOnDateReadable":"December 22nd, 2025"},"versionCreatedAt":"2025-07-15 11:21:53","video":"","vorDoi":"10.1007/s12217-025-10209-0","vorDoiUrl":"https://doi.org/10.1007/s12217-025-10209-0","workflowStages":[]},"version":"v1","identity":"rs-7046707","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7046707","identity":"rs-7046707","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}