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Abstract
The timing of life on Earth is remarkable: between individuals of the same species, a highly similar temporal pattern is observed, with shared periods of activity and inactivity each day. At the individual level, this means that over the course of a single day, a person alternates between two states. They are either upright, active, and communicative or they lie down in a state of (un)consciousness called sleep where even the characteristic of neuronal signals in the brain shows distinctive properties. The circadian clock governs both of these time stamps-activity and (apparent) inactivity-making them come and go consistently at the same approximate time each day. This behavior thus represents the meeting of two pervasive systems: the circadian clock and metabolism. In this article, we will describe what is known about how the circadian clock anticipates daily changes in oxygen usage, how circadian clock regulation may relate to normal physiology, and to hypoxia and ischemia that can result from pathologies such as myocardial infarction and stroke.
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Affiliation(s)
- Francesca Sartor
- Institute of Medical Psychology, Medical Faculty, LMU Munich, Germany (F.S., B.F.-B., M.M.)
| | - Borja Ferrero-Bordera
- Institute of Medical Psychology, Medical Faculty, LMU Munich, Germany (F.S., B.F.-B., M.M.)
| | - Jeffrey Haspel
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Washington University School of Medicine, St. Louis, MO (J.H.)
| | - Markus Sperandio
- Institute for Cardiovascular Physiology and Pathophysiology, Walter Brendel Center for Experimental Medicine, and the Biomedical Center (BMC), Medical Faculty, LMU Munich, Germany (M.S.)
| | - Paul M Holloway
- Radcliffe Department of Medicine, University of Oxford, United Kingdom (P.M.H.)
| | - Martha Merrow
- Institute of Medical Psychology, Medical Faculty, LMU Munich, Germany (F.S., B.F.-B., M.M.)
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Li Y, Chen Y, Kuang J, Deng S, Wang Y. Intermittent hypoxia induces hepatic senescence through promoting oxidative stress in a mouse model. Sleep Breath 2024; 28:183-191. [PMID: 37453998 DOI: 10.1007/s11325-023-02878-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 06/20/2023] [Accepted: 06/23/2023] [Indexed: 07/18/2023]
Abstract
PURPOSE Metabolic-associated fatty liver disease (MAFLD) is an aging-related disease. Obstructive sleep apnea (OSA) may cause MAFLD. This study aimed to explore whether or not intermittent hypoxia (IH), the hallmark of OSA, induces liver aging through oxidative stress. METHODS C57BL/6J male mice were administered normal air (control), IH, or antioxidant tempol + IH daily for 6 weeks before the collection of serum and liver tissue samples. A histological examination was conducted to assess liver aging. ELISA was performed to measure liver function indicator levels in the serum and oxidative stress indicator activities in the liver. Western blot analysis was carried out to determine the protein expression of the markers related to oxidative stress, inflammation, and senescence. RESULTS Compared with control, IH resulted in significant increases in serum ALT, AST, and TG levels in mice (all P < 0.001), along with lobular inflammation and accumulation of collagen and fat in the liver. The protein levels of inflammatory factors and senescent markers were significantly increased in the IH mouse liver compared with those in the control mouse liver. Meanwhile, IH significantly reduced SOD and CAT activities while enhancing p22phox and Nrf2 protein expression in mouse liver compared with control. Importantly, antioxidant therapy with tempol effectively abrogated the effects of IH on oxidative stress response and aging-related liver injury. CONCLUSIONS Our findings suggest that IH induces liver inflammation and aging through oxidative stress. OSA may exacerbate target organ aging and participate in target organ damage. Strategies targeting oxidative stress may prevent and treat OSA-related MAFLD.
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Affiliation(s)
- Yayong Li
- Department of Emergency, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Yuanguo Chen
- Department of Emergency, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Jingjie Kuang
- Department of Geriatrics, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Silei Deng
- Department of Geriatrics, The Second Xiangya Hospital of Central South University, Changsha, China
| | - Yina Wang
- Department of Geriatrics, The Second Xiangya Hospital of Central South University, Changsha, China.
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Koritala BSC, Gaspar LS, Bhadri SS, Massie KS, Lee YY, Paulose J, Smith DF. Murine Pro-Inflammatory Responses to Acute and Sustained Intermittent Hypoxia: Implications for Obstructive Sleep Apnea Research. Laryngoscope 2024; 134 Suppl 4:S1-S11. [PMID: 37540033 PMCID: PMC10838350 DOI: 10.1002/lary.30915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/05/2023] [Accepted: 07/14/2023] [Indexed: 08/05/2023]
Abstract
OBJECTIVES Obstructive sleep apnea (OSA) is characterized by chronic systemic inflammation; however, the mechanisms underlying these pathologic consequences are incompletely understood. Our objective was to determine the effects of short- versus long-term exposure to intermittent hypoxia (IH) on pro-inflammatory mediators within vulnerable organs impacted by OSA. STUDY DESIGN Experimental animal study. METHODS A total of 8-10 week old C57BL/6J mice were exposed to normoxic or IH conditions for 7 days (short-term) or 6 weeks (long-term) under 12 h light, 12 h dark cycles. After exposure, multiple tissues were collected over a 24 h period. These tissues were processed and evaluated for gene expression and protein levels of pro-inflammatory mediators from peripheral tissues. RESULTS We observed a global decrease in immune response pathways in the heart, lung, and liver compared with other peripheral organs after short-term exposure to IH. Although there were tissue-specific alterations in the gene expression of pro-inflammatory mediators, with down-regulation in the lung and up-regulation in the heart, we also observed reduced protein levels of pro-inflammatory mediators in the serum, lung, and heart following short-term exposure to IH. Long-term exposure to IH resulted in an overall increase in the levels of inflammatory mediators in the serum, lung, and heart. CONCLUSIONS We demonstrated novel, longitudinal changes in the inflammatory cascade in a mouse model of OSA. The duration of exposure to IH led to significant variability of inflammatory responses within blood and cardiopulmonary tissues. Our findings further elucidate how inflammatory responses change over the course of the disease in vulnerable organs. LEVEL OF EVIDENCE NA Laryngoscope, 134:S1-S11, 2024.
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Affiliation(s)
- Bala S. C. Koritala
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Laetitia S. Gaspar
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Center for Neuroscience and Cell Biology, University of Coimbra, 3004-504 Coimbra, Portugal
| | - Shweta S. Bhadri
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Kyla S. Massie
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- University of California San Diego, San Diego, California, 92093, USA
| | - Yin Yeng Lee
- Department of Pediatrics, Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Department of Pharmacology and Systems Physiology, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Jiffin Paulose
- Department of Pediatrics, Division of Human Genetics, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
| | - David F. Smith
- Division of Pediatric Otolaryngology-Head and Neck Surgery, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- Department of Otolaryngology-Head and Neck Surgery, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
- Division of Pulmonary Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- The Sleep Center, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
- The Center for Circadian Medicine, Cincinnati Children’s Hospital Medical Center, Cincinnati, OH 45229, USA
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Ding M, Lu Y, Huang X, Xing C, Hou S, Wang D, Zhang Y, Wang W, Zhang C, Zhang M, Meng F, Liu K, Liu G, Zhao J, Song L. Acute hypoxia induced dysregulation of clock-controlled ovary functions. Front Physiol 2022; 13:1024038. [PMID: 36620217 PMCID: PMC9816144 DOI: 10.3389/fphys.2022.1024038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022] Open
Abstract
High altitudes or exposure to hypoxia leads to female reproductive disorders. Circadian clocks are intrinsic time-tracking systems that enable organisms to adapt to the Earth's 24-h light/dark cycle, which can be entrained by other environmental stimuli to regulate physiological and pathological responses. In this study, we focused on whether ovarian circadian clock proteins were involved in regulating female reproductive dysfunction under hypoxic conditions. Hypobaric hypoxia was found to induce a significantly prolonged estrous cycle in female mice, accompanied by follicular atresia, pituitary/ovarian hormone synthesis disorder, and decreased LHCGR expression in the ovaries. Under the same conditions, the levels of the ovarian circadian clock proteins, CLOCK and BMAL1, were suppressed, whereas E4BP4 levels were upregulated. Results from granulosa cells (GCs) further demonstrated that CLOCK: BMAL1 and E4BP4 function as transcriptional activators and repressors of LHCGR in ovarian GCs, respectively, whose responses were mediated by HIF1ɑ-dependent (E4BP4 upregulation) and ɑ-independent (CLOCK and BMAL1 downregulation) manners. The LHCGR agonist was shown to efficiently recover the impairment of ovulation-related gene (EREG and PGR) expression in GCs induced by hypoxia. We conclude that hypoxia exposure causes dysregulation of ovarian circadian clock protein (CLOCK, BMAL1, and E4BP4) expression, which mediates female reproductive dysfunction by impairing LHCGR-dependent signaling events. Adjusting the timing system or recovering the LHCGR level in the ovaries may be helpful in overcoming female reproductive disorders occurring in the highlands.
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Affiliation(s)
- Mengnan Ding
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Yarong Lu
- Beijing Institute of Basic Medical Sciences, Beijing, China,Henan University Joint National Laboratory for Antibody Drug Engineering, Kaifeng, China
| | - Xin Huang
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Chen Xing
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Shaojun Hou
- Beijing Institute of Basic Medical Sciences, Beijing, China,Anhui Medical University, Hefei, China,School of Pharmacy, Jiamus University, Jiamusi, China
| | - Dongxue Wang
- Beijing Institute of Basic Medical Sciences, Beijing, China,School of Pharmacy, Jiamus University, Jiamusi, China
| | - Yifan Zhang
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Wei Wang
- Beijing Institute of Basic Medical Sciences, Beijing, China,School of Pharmacy, Jiamus University, Jiamusi, China
| | - Chongchong Zhang
- Beijing Institute of Basic Medical Sciences, Beijing, China,Henan University Joint National Laboratory for Antibody Drug Engineering, Kaifeng, China
| | - Min Zhang
- Beijing Institute of Basic Medical Sciences, Beijing, China,Anhui Medical University, Hefei, China
| | - Fanfei Meng
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Kun Liu
- Beijing Institute of Basic Medical Sciences, Beijing, China
| | - Guangchao Liu
- Henan University Joint National Laboratory for Antibody Drug Engineering, Kaifeng, China
| | - Jincheng Zhao
- School of Pharmacy, Jiamus University, Jiamusi, China
| | - Lun Song
- Beijing Institute of Basic Medical Sciences, Beijing, China,Anhui Medical University, Hefei, China,School of Pharmacy, Jiamus University, Jiamusi, China,College of Life Science, Henan Normal University, Xinxiang, China,*Correspondence: Lun Song,
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Prenatal Hypoxia Affects Foetal Cardiovascular Regulatory Mechanisms in a Sex- and Circadian-Dependent Manner: A Review. Int J Mol Sci 2022; 23:ijms23052885. [PMID: 35270026 PMCID: PMC8910900 DOI: 10.3390/ijms23052885] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 02/28/2022] [Accepted: 03/05/2022] [Indexed: 11/17/2022] Open
Abstract
Prenatal hypoxia during the prenatal period can interfere with the developmental trajectory and lead to developing hypertension in adulthood. Prenatal hypoxia is often associated with intrauterine growth restriction that interferes with metabolism and can lead to multilevel changes. Therefore, we analysed the effects of prenatal hypoxia predominantly not associated with intrauterine growth restriction using publications up to September 2021. We focused on: (1) The response of cardiovascular regulatory mechanisms, such as the chemoreflex, adenosine, nitric oxide, and angiotensin II on prenatal hypoxia. (2) The role of the placenta in causing and attenuating the effects of hypoxia. (3) Environmental conditions and the mother's health contribution to the development of prenatal hypoxia. (4) The sex-dependent effects of prenatal hypoxia on cardiovascular regulatory mechanisms and the connection between hypoxia-inducible factors and circadian variability. We identified that the possible relationship between the effects of prenatal hypoxia on the cardiovascular regulatory mechanism may vary depending on circadian variability and phase of the days. In summary, even short-term prenatal hypoxia significantly affects cardiovascular regulatory mechanisms and programs hypertension in adulthood, while prenatal programming effects are not only dependent on the critical period, and sensitivity can change within circadian oscillations.
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