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Faraci FM, Scheer FA. Hypertension: Causes and Consequences of Circadian Rhythms in Blood Pressure. Circ Res 2024; 134:810-832. [PMID: 38484034 PMCID: PMC10947115 DOI: 10.1161/circresaha.124.323515] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 02/16/2024] [Indexed: 03/19/2024]
Abstract
Hypertension is extremely common, affecting approximately 1 in every 2 adults globally. Chronic hypertension is the leading modifiable risk factor for cardiovascular disease and premature mortality worldwide. Despite considerable efforts to define mechanisms that underlie hypertension, a potentially major component of the disease, the role of circadian biology has been relatively overlooked in both preclinical models and humans. Although the presence of daily and circadian patterns has been observed from the level of the genome to the whole organism, the functional and structural impact of biological rhythms, including mechanisms such as circadian misalignment, remains relatively poorly defined. Here, we review the impact of daily rhythms and circadian systems in regulating blood pressure and the onset, progression, and consequences of hypertension. There is an emphasis on the impact of circadian biology in relation to vascular disease and end-organ effects that, individually or in combination, contribute to complex phenotypes such as cognitive decline and the loss of cardiac and brain health. Despite effective treatment options for some individuals, control of blood pressure remains inadequate in a substantial portion of the hypertensive population. Greater insight into circadian biology may form a foundation for novel and more widely effective molecular therapies or interventions to help in the prevention, treatment, and management of hypertension and its related pathophysiology.
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Affiliation(s)
- Frank M. Faraci
- Department of Internal Medicine, Francois M. Abboud Cardiovascular Center, Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1081
- Department of Neuroscience and Pharmacology, Francois M. Abboud Cardiovascular Center, Carver College of Medicine, University of Iowa, Iowa City, IA 52242-1081
| | - Frank A.J.L. Scheer
- Division of Sleep Medicine, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, 02115
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital, Boston, Massachusetts, 02115
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2
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Walton JC, Bumgarner JR, Nelson RJ. Sex Differences in Circadian Rhythms. Cold Spring Harb Perspect Biol 2022; 14:cshperspect.a039107. [PMID: 35101914 DOI: 10.1101/cshperspect.a039107] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Sex as a biological variable is the focus of much literature and has been emphasized by the National Institutes of Health, in part, to remedy a long history of male-dominated studies in preclinical and clinical research. We propose that time-of-day is also a crucial biological variable in biomedical research. In common with sex differences, time-of-day should be considered in analyses and reported to improve reproducibility of studies and to provide the appropriate context to the conclusions. Endogenous circadian rhythms are present in virtually all living organisms, including bacteria, plants, invertebrates, and vertebrates. Virtually all physiological and behavioral processes display daily fluctuations in optimal performance that are driven by these endogenous circadian clocks; importantly, many of those circadian rhythms also show sex differences. In this review, we describe some of the documented sex differences in circadian rhythms.
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Affiliation(s)
- James C Walton
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Jacob R Bumgarner
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia 26506, USA
| | - Randy J Nelson
- Department of Neuroscience, Rockefeller Neuroscience Institute, West Virginia University, Morgantown, West Virginia 26506, USA
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3
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Walton SL, Tjongue M, Tare M, Kwok E, Probyn M, Parkington HC, Bertram JF, Moritz KM, Denton KM. Chronic low alcohol intake during pregnancy programs sex-specific cardiovascular deficits in rats. Biol Sex Differ 2019; 10:21. [PMID: 31010438 PMCID: PMC6477739 DOI: 10.1186/s13293-019-0235-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 04/02/2019] [Indexed: 02/08/2023] Open
Abstract
Background Exposure to an adverse environment in early life can have lifelong consequences for risk of cardiovascular disease. Maternal alcohol (ethanol) intake is common and associated with a variety of harmful effects to the fetus. However, examining the effects on the cardiovascular system in adult offspring has largely been neglected. The objectives of this study were to investigate the influence of chronic, low ethanol consumption throughout pregnancy on blood pressure, vascular reactivity and wall stiffness, all key determinants of cardiovascular health, in both male and female rat offspring. Methods Female Sprague-Dawley rats were fed an ad libitum liquid diet ± 6% vol/vol ethanol throughout pregnancy. Male and female offspring were studied at 12 months of age. Arterial pressure, heart rate and locomotor activity were measured over 7 days via radiotelemetry. Renal lobar arteries were isolated and studied using wire and pressure myography. Results Basal mean arterial pressure in female ethanol-exposed rats was reduced by ~ 5–6 mmHg compared to control female offspring, whereas arterial pressure was unaffected in male offspring. Ethanol-exposed offspring had an attenuated pressor response to an acute restraint stress, with this effect most evident in females. Renal artery function was not affected by prenatal ethanol exposure. Conclusions We show for the first time that low level chronic maternal alcohol intake during pregnancy influences arterial pressure in adult offspring in the absence of fetal growth restriction. Electronic supplementary material The online version of this article (10.1186/s13293-019-0235-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sarah L Walton
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia.,Department of Physiology, Monash University, Clayton, VIC, Australia
| | - Melissa Tjongue
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia.,Department of Physiology, Monash University, Clayton, VIC, Australia
| | - Marianne Tare
- Department of Physiology, Monash University, Clayton, VIC, Australia.,Monash Rural Health, Churchill, VIC, Australia
| | - Edmund Kwok
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia.,Department of Physiology, Monash University, Clayton, VIC, Australia
| | - Megan Probyn
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia
| | | | - John F Bertram
- Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC, Australia.,Kidney Developmental Programming and Disease Laboratory, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia
| | - Karen M Moritz
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia.,Child Health Research Centre, The University of Queensland, St Lucia, QLD, Australia
| | - Kate M Denton
- Cardiovascular Disease Program, Monash Biomedicine Discovery Institute, Clayton, VIC, Australia. .,Department of Physiology, Monash University, Clayton, VIC, Australia.
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4
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Boese AC, Chang L, Yin KJ, Chen YE, Lee JP, Hamblin MH. Sex differences in abdominal aortic aneurysms. Am J Physiol Heart Circ Physiol 2018; 314:H1137-H1152. [PMID: 29350999 DOI: 10.1152/ajpheart.00519.2017] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Abdominal aortic aneurysm (AAA) is a vascular disorder with a high case fatality rate in the instance of rupture. AAA is a multifactorial disease, and the etiology is still not fully understood. AAA is more likely to occur in men, but women have a greater risk of rupture and worse prognosis. Women are reportedly protected against AAA possibly by premenopausal levels of estrogen and are, on average, diagnosed at older ages than men. Here, we review the present body of research on AAA pathophysiology in humans, animal models, and cultured cells, with an emphasis on sex differences and sex steroid hormone signaling.
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Affiliation(s)
- Austin C Boese
- Department of Pharmacology, Tulane University School of Medicine , New Orleans, Louisiana
| | - Lin Chang
- Center for Advanced Models for Translational Sciences and Therapeutics, Department of Internal Medicine, University of Michigan , Ann Arbor, Michigan
| | - Ke-Jie Yin
- Department of Neurology, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Y Eugene Chen
- Center for Advanced Models for Translational Sciences and Therapeutics, Department of Internal Medicine, University of Michigan , Ann Arbor, Michigan
| | - Jean-Pyo Lee
- Department of Physiology, Tulane University School of Medicine , New Orleans, Louisiana.,Center for Stem Cell Research and Regenerative Medicine , New Orleans, Louisiana
| | - Milton H Hamblin
- Department of Pharmacology, Tulane University School of Medicine , New Orleans, Louisiana
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5
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Epochs in the depressor/pressor balance of the renin-angiotensin system. Clin Sci (Lond) 2017; 130:761-71. [PMID: 27128801 DOI: 10.1042/cs20150939] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 02/01/2016] [Indexed: 12/17/2022]
Abstract
The renin-angiotensin system (RAS) plays a commanding role in the regulation of extracellular fluid homoeostasis. Tigerstadt and Bergman first identified the RAS more than two centuries ago. By the 1980s a voyage of research and discovery into the mechanisms and actions of this system led to the development of drugs that block the RAS, which have become the mainstay for the treatment of cardiovascular and renal disease. In the last 25 years new components of the RAS have come to light, including the angiotensin type 2 receptor (AT2R) and the angiotensin-converting enzyme 2 (ACE2)/angiotensin-(1-7) [Ang(1-7)]/Mas receptor (MasR) axis. These have been shown to counter the classical actions of angiotensin II (AngII) at the predominant angiotensin type 1 receptor (AT1R). Our studies, and those of others, have demonstrated that targeting these depressor RAS pathways may be therapeutically beneficial. It is apparent that the evolution of both the pressor and depressor RAS pathways is distinct throughout life and that the depressor/pressor balance of the RAS vary between the sexes. These temporal patterns of expression suggest that therapies targeting the RAS could be optimized for discrete epochs in life.
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6
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Barsha G, Denton KM, Mirabito Colafella KM. Sex- and age-related differences in arterial pressure and albuminuria in mice. Biol Sex Differ 2016; 7:57. [PMID: 27895890 PMCID: PMC5109725 DOI: 10.1186/s13293-016-0110-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Accepted: 10/22/2016] [Indexed: 11/25/2022] Open
Abstract
Background Animal models have become valuable experimental tools for understanding the pathophysiology and therapeutic interventions in cardiovascular disease. Yet to date, few studies document the age- and sex-related differences in arterial pressure, circadian rhythm, and renal function in normotensive mice under basal conditions, across the life span. We hypothesized that mice display similar sex- and age-related differences in arterial pressure and renal function to humans. Methods Mean arterial pressure (MAP) and circadian rhythm of arterial pressure were measured over 3 days via radiotelemetry, in 3- and 5-month-old (adult) and 14- and 18-month-old (aged) FVB/N and in 5-month-old (adult) C57BL/6 male and female normotensive mice. In FVB/N mice, albuminuria from 24-h urine samples as well as body, heart, and kidney weights were measured at each age. Results Twenty-four-hour MAP was greater in males than females at 3, 5, and 14 months of age. A similar sex difference in arterial pressure was observed in C57BL/6 mice at 5 months of age. In FVB/N mice, 24-h MAP increased with age, with females displaying a greater increase between 3 and 18 months of age than males, such that MAP was no longer different between the sexes at 18 months of age. A circadian pattern was observed in arterial pressure, heart rate, and locomotor activity, with values for each greater during the active (night/dark) than the inactive (day/light) period. The night-day dip in MAP was greater in males and increased with age in both sexes. Albuminuria was greater in males than females, increased with age in both sexes, and rose to a greater level in males than females at 18 months of age. Conclusions Arterial pressure and albuminuria increase in an age- and sex-specific manner in mice, similar to patterns observed in humans. Thus, mice represent a useful model for studying age and sex differences in the regulation of arterial pressure and renal disease. Understanding the mechanisms that underlie the pathophysiology of cardiovascular disease may lead to new and better-tailored therapies for men and women.
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Affiliation(s)
- Giannie Barsha
- Cardiovascular Program, Monash Biomedicine Discovery Institute, Clayton, Australia.,Department of Physiology, Monash University, 26 Innovation Walk (Building 13F), Clayton, VIC 3800 Australia
| | - Kate M Denton
- Cardiovascular Program, Monash Biomedicine Discovery Institute, Clayton, Australia.,Department of Physiology, Monash University, 26 Innovation Walk (Building 13F), Clayton, VIC 3800 Australia
| | - Katrina M Mirabito Colafella
- Cardiovascular Program, Monash Biomedicine Discovery Institute, Clayton, Australia.,Department of Physiology, Monash University, 26 Innovation Walk (Building 13F), Clayton, VIC 3800 Australia
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7
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Hilliard LM, Denton KM. Transcutaneous assessment of glomerular filtration rate in unanesthetized rats using a small animal imager: impact on arterial pressure, heart rate, and activity. Physiol Rep 2016. [PMCID: PMC5064127 DOI: 10.14814/phy2.12723] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Lucinda M. Hilliard
- Cardiovascular Program; Monash Biomedicine Discovery Institute and Departments of Physiology; Monash University; Melbourne Victoria 3800 Australia
| | - Kate M. Denton
- Cardiovascular Program; Monash Biomedicine Discovery Institute and Departments of Physiology; Monash University; Melbourne Victoria 3800 Australia
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8
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Hilliard LM, Colafella KMM, Bulmer LL, Puelles VG, Singh RR, Ow CPC, Gaspari T, Drummond GR, Evans RG, Vinh A, Denton KM. Chronic recurrent dehydration associated with periodic water intake exacerbates hypertension and promotes renal damage in male spontaneously hypertensive rats. Sci Rep 2016; 6:33855. [PMID: 27653548 PMCID: PMC5032121 DOI: 10.1038/srep33855] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 09/05/2016] [Indexed: 01/12/2023] Open
Abstract
Epidemiological evidence links recurrent dehydration associated with periodic water intake with chronic kidney disease (CKD). However, minimal attention has been paid to the long-term impact of periodic water intake on the progression of CKD and underlying mechanisms involved. Therefore we investigated the chronic effects of recurrent dehydration associated with periodic water restriction on arterial pressure and kidney function and morphology in male spontaneously hypertensive rats (SHR). Arterial pressure increased and glomerular filtration rate decreased in water-restricted SHR. This was observed in association with cyclic changes in urine osmolarity, indicative of recurrent dehydration. Additionally, water-restricted SHR demonstrated greater renal fibrosis and an imbalance in favour of pro-inflammatory cytokine-producing renal T cells compared to their control counterparts. Furthermore, urinary NGAL levels were greater in water-restricted than control SHR. Taken together, our results provide significant evidence that recurrent dehydration associated with chronic periodic drinking hastens the progression of CKD and hypertension, and suggest a potential role for repetitive bouts of acute renal injury driving renal inflammatory processes in this setting. Further studies are required to elucidate the specific pathways that drive the progression of recurrent dehydration-induced kidney disease.
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Affiliation(s)
- Lucinda M Hilliard
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, 3800, Australia
| | - Katrina M Mirabito Colafella
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, 3800, Australia
| | - Louise L Bulmer
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, 3800, Australia
| | - Victor G Puelles
- Department of Anatomy and Developmental Biology, Monash University, Melbourne, Victoria, 3800, Australia
| | - Reetu R Singh
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, 3800, Australia
| | - Connie P C Ow
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, 3800, Australia
| | - Tracey Gaspari
- Department of Pharmacology, Monash University, Melbourne, Victoria, 3800 Australia
| | - Grant R Drummond
- Department of Pharmacology, Monash University, Melbourne, Victoria, 3800 Australia
| | - Roger G Evans
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, 3800, Australia
| | - Antony Vinh
- Department of Pharmacology, Monash University, Melbourne, Victoria, 3800 Australia
| | - Kate M Denton
- Cardiovascular Disease Program, Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria, 3800, Australia
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9
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Elmarakby AA, Bhatia K, Crislip R, Sullivan JC. Hemodynamic responses to acute angiotensin II infusion are exacerbated in male versus female spontaneously hypertensive rats. Physiol Rep 2016; 4:4/1/e12677. [PMID: 26755738 PMCID: PMC4760407 DOI: 10.14814/phy2.12677] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We previously reported that male spontaneously hypertensive rats (SHRs) are more sensitive to chronic angiotensin (Ang) II‐induced hypertension compared with female rats. This study was designed to test the hypothesis that anesthetized male SHRs are also more responsive to acute Ang II‐induced increases in blood pressure and renal hemodynamic changes when compared with female SHRs. Baseline mean arterial pressure (MAP) was higher in male SHRs than in female SHRs (135 ± 2 vs. 124 ± 4 mmHg, P < 0.05). Acute intravenous infusion of Ang II (5 ng/kg/min) for 60 minutes significantly increased MAP to 148 ± 2 mmHg in male SHRs (P < 0.05) without a significant change in MAP in female SHRs. Baseline glomerular filtration rate (GFR) was also higher in male SHRs than in female SHRs (2.6 ± 0.3 vs. 1.3 ± 0.1 mL/min, P < 0.05). Ang II infusion for 60 min significantly decreased GFR in male SHRs (2.0 ± 0.2 mL/min; P < 0.05) without significant changes in urine flow rate, sodium, or chloride excretion. In contrast, Ang II infusion increased GFR in female SHRs (1.9 ± 0.2 mL/min; P < 0.05). The increase in GFR upon Ang II infusion in female SHRs was associated with increases in urine flow rate (4.3 ± 0.3 to 7.1 ± 0.9 μL/min), sodium excretion (0.16 ± 0.04 to 0.4 ± 0.1 μmol/min), and chloride excretion (0.7 ± 0.08 to 1.1 ± 0.1 μmol/min; for all P < 0.05). These findings support the hypothesis that there is sex difference in response to acute Ang II infusion in SHRs with females being less responsive to Ang II‐induced elevations in blood pressure and decreases in GFR relative to male SHRs.
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Affiliation(s)
- Ahmed A Elmarakby
- Departments of Oral Biology, Augusta University, Augusta, Georgia Departments of Pharmacology & Toxicology, Augusta University, Augusta, Georgia
| | - Kanchan Bhatia
- Departments of Physiology, Augusta University, Augusta, Georgia
| | - Ryan Crislip
- Departments of Physiology, Augusta University, Augusta, Georgia
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Zimmerman MA, Baban B, Tipton AJ, O'Connor PM, Sullivan JC. Chronic ANG II infusion induces sex-specific increases in renal T cells in Sprague-Dawley rats. Am J Physiol Renal Physiol 2014; 308:F706-12. [PMID: 25503730 DOI: 10.1152/ajprenal.00446.2014] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Accepted: 12/02/2014] [Indexed: 01/09/2023] Open
Abstract
Recent studies suggest that sex of the animal and T cell impact ANG II hypertension in Rag(-/-) mice, with females being protected relative to males. This study tested the hypothesis that ANG II results in greater increases in proinflammatory T cells and cytokines in males than in females. Male and female Sprague-Dawley (SD) rats, aged 12 wk, were treated with vehicle or ANG II (200 ng·kg(-1)·min(-1)) for 2 wk. Renal CD4(+) T cells and Tregs were comparable between vehicle-treated males and females, although males expressed more Th17 and IL-17(+) T cells and fewer IL-10(+) T cells than females. ANG II resulted in greater increases in CD4(+) T cells, Th17 cells, and IL-17(+) cells in males; Tregs increased only in females. We previously showed that ANG (1-7) antagonizes ANG II-induced increases in blood pressure in females and ANG (1-7) has been suggested to be anti-inflammatory. Renal ANG (1-7) levels were greater in female SD at baseline and following ANG II infusion. Additional rats were treated with ANG II plus the ANG (1-7)-mas receptor antagonist A-779 (48 μg·kg(-1)·h(-1)) to test the hypothesis that greater ANG (1-7) in females results in more Tregs relative to males. Inhibition of ANG (1-7) did not alter renal T cells in either sex. In conclusion, ANG II induces a sex-specific effect on the renal T cell profile. Males have greater increases in proinflammatory T cells, and females have greater increases in anti-inflammatory Tregs; however, sex differences in the renal T cell profile are not mediated by ANG (1-7).
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Affiliation(s)
| | - Babak Baban
- Department of Oral Biology, Georgia Regents University, Augusta, Georgia
| | - Ashlee J Tipton
- Department of Physiology, Georgia Regents University, Augusta, Georgia; and
| | - Paul M O'Connor
- Department of Physiology, Georgia Regents University, Augusta, Georgia; and
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11
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Abstract
Sex differences exist in the regulation of arterial pressure and renal function by the renin-angiotensin system (RAS). This may in part stem from a differential balance in the pressor and depressor arms of the RAS. In males, the ACE/AngII/AT(1)R pathways are enhanced, whereas, in females, the balance is shifted towards the ACE2/Ang(1-7)/MasR and AT(2)R pathways. Evidence clearly demonstrates that premenopausal women, as compared to aged-matched men, are protected from renal and cardiovascular disease, and this differential balance of the RAS between the sexes likely contributes. With aging, this cardiovascular protection in women is lost and this may be related to loss of estrogen postmenopause but the possible contribution of other sex hormones needs to be further examined. Restoration of these RAS depressor pathways in older women, or up-regulation of these in males, represents a therapeutic target that is worth pursuing.
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12
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Samuel P, Khan MA, Nag S, Inagami T, Hussain T. Angiotensin AT(2) receptor contributes towards gender bias in weight gain. PLoS One 2013; 8:e48425. [PMID: 23341867 PMCID: PMC3546084 DOI: 10.1371/journal.pone.0048425] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Accepted: 09/25/2012] [Indexed: 11/19/2022] Open
Abstract
Obesity is a major disease condition, in turn leading to pathological changes collectively recognized as metabolic syndrome. Recently angiotensin receptor AT(2)R has been associated negatively with body weight (BW) gain in male mice. However, the gender differences in AT(2)R and BW changes have not been studied. To understand the gender based role of AT(2)R involving BW changes, we fed male and female wild type (WT) and AT(2)R knock out (AT(2)KO) mice with C57BL6 background with high fat diet (HFD) for 16 weeks. The male AT(2)KO had higher HFD calorie intake (WT: 1280±80; AT(2)KO:1680±80 kcal) but gained less BW compared with the WT (WT: 13; AT(2)KO: 6 g). Contrary to the male animals, the female AT(2)KO mice with equivalent caloric intake (WT: 1424±48; AT(2)KO:1456±80 kcal) gained significantly more BW than the WT mice (WT: 9 g; AT(2)KO: 15 g). The male AT(2)KO on HFD displayed lower plasma insulin level, less impaired glucose tolerance (GT), and higher plasma T3 compared with WT males on HFD; whereas the female AT(2)KO mice on HFD showed elevated levels of plasma insulin, more impaired GT, lower plasma T3 and higher free fatty acid and hepatic triglycerides compared with WT females on HFD. Interestingly, compared with WT, AT(2)KO female mice had significantly lower estrogen, which was further reduced by HFD. These results suggest that AT(2)R in female mice via potentially regulating estrogen may have protective role against BW gain and impaired glucose tolerance and lipid metabolism.
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Affiliation(s)
- Preethi Samuel
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas, United States of America
| | - Mohammad Azhar Khan
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas, United States of America
| | - Sourashish Nag
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas, United States of America
| | - Tadashi Inagami
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, United States of America
| | - Tahir Hussain
- Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston, Houston, Texas, United States of America
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13
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Sampson AK, Hilliard LM, Moritz KM, Thomas MC, Tikellis C, Widdop RE, Denton KM. The arterial depressor response to chronic low-dose angiotensin II infusion in female rats is estrogen dependent. Am J Physiol Regul Integr Comp Physiol 2011; 302:R159-65. [PMID: 22031787 DOI: 10.1152/ajpregu.00256.2011] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The complex role of the renin-angiotensin-system (RAS) in arterial pressure regulation has been well documented. Recently, we demonstrated that chronic low-dose angiotensin II (ANG II) infusion decreases arterial pressure in female rats via an AT(2)R-mediated mechanism. Estrogen can differentially regulate components of the RAS and is known to influence arterial pressure regulation. We hypothesized that AT(2)R-mediated depressor effects evident in females were estrogen dependent and thus would be abolished by ovariectomy and restored by estrogen replacement. Female Sprague-Dawley rats underwent ovariectomy or sham surgery and were treated with 17β-estradiol or placebo. Mean arterial pressure (MAP) was measured via telemetry in response to a 2-wk infusion of ANG II (50 ng·kg(-1)·min(-1) sc) or saline. MAP significantly decreased in females treated with ANG II (-10 ± 2 mmHg), a response that was abolished by ovariectomy (+4 ± 2 mmHg) and restored with estrogen replacement (-6 ± 2 mmHg). Cardiac and renal gene expression of components of the RAS was differentially regulated by estrogen, such that overall, estrogen shifted the balance of the RAS toward the vasodilatory axis. In conclusion, estrogen-dependent mechanisms offset the vasopressor actions of ANG II by enhancing RAS vasodilator pathways in females. This highlights the potential for these vasodilator pathways as therapeutic targets, particularly in women.
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Affiliation(s)
- Amanda K Sampson
- Department of Physiology, Monash University, Clayton, Victoria, Australia.
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15
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Abstract
Hypertension is a major risk factor for cardiovascular disease and death. The "silent" rise of blood pressure that occurs over time is largely asymptomatic. However, its impact is deafening-causing and exacerbating cardiovascular disease, end-organ damage, and death. The present article addresses recent observations from human and animal studies that provide new insights into how the circadian clock regulates blood pressure, contributes to hypertension, and ultimately evolves vascular disease. Further, the molecular components of the circadian clock and their relationship with locomotor activity, metabolic control, fluid balance, and vascular resistance are discussed with an emphasis on how these novel, circadian clock-controlled mechanisms contribute to hypertension.
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Affiliation(s)
- R Daniel Rudic
- Department of Pharmacology and Toxicology, 1120 15th St., Medical College of Georgia, Augusta, GA 30912, USA.
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16
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Sampson AK, Moritz KM, Jones ES, Flower RL, Widdop RE, Denton KM. Enhanced Angiotensin II Type 2 Receptor Mechanisms Mediate Decreases in Arterial Pressure Attributable to Chronic Low-Dose Angiotensin II in Female Rats. Hypertension 2008; 52:666-71. [DOI: 10.1161/hypertensionaha.108.114058] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Amanda K. Sampson
- From the Departments of Physiology (A.K.S., R.L.F., K.M.D.) and Pharmacology (E.S.J., R.E.W.), Monash University, Clayton, Victoria; and the School of Biomedical Sciences (K.M.M.), University of Queensland, Queensland, Australia
| | - Karen M. Moritz
- From the Departments of Physiology (A.K.S., R.L.F., K.M.D.) and Pharmacology (E.S.J., R.E.W.), Monash University, Clayton, Victoria; and the School of Biomedical Sciences (K.M.M.), University of Queensland, Queensland, Australia
| | - Emma S. Jones
- From the Departments of Physiology (A.K.S., R.L.F., K.M.D.) and Pharmacology (E.S.J., R.E.W.), Monash University, Clayton, Victoria; and the School of Biomedical Sciences (K.M.M.), University of Queensland, Queensland, Australia
| | - Rebecca L. Flower
- From the Departments of Physiology (A.K.S., R.L.F., K.M.D.) and Pharmacology (E.S.J., R.E.W.), Monash University, Clayton, Victoria; and the School of Biomedical Sciences (K.M.M.), University of Queensland, Queensland, Australia
| | - Robert E. Widdop
- From the Departments of Physiology (A.K.S., R.L.F., K.M.D.) and Pharmacology (E.S.J., R.E.W.), Monash University, Clayton, Victoria; and the School of Biomedical Sciences (K.M.M.), University of Queensland, Queensland, Australia
| | - Kate M. Denton
- From the Departments of Physiology (A.K.S., R.L.F., K.M.D.) and Pharmacology (E.S.J., R.E.W.), Monash University, Clayton, Victoria; and the School of Biomedical Sciences (K.M.M.), University of Queensland, Queensland, Australia
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