1
|
Singh A, Yilmaz D, Wehrle E, Kuhn GA, Müller R. Daily rhythms in metabolic and locomotor behaviour of prematurely ageing PolgA mice. FEBS Open Bio 2024. [PMID: 39073017 DOI: 10.1002/2211-5463.13866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2024] [Accepted: 07/17/2024] [Indexed: 07/30/2024] Open
Abstract
Ageing is an inherent and intricate biological process that takes place in living organisms as time progresses. It involves the decline of multiple physiological functions, leading to body structure and overall performance modifications. The ageing process differs among individuals and is influenced by various factors, including lifestyle, environment and genetic makeup. Metabolic changes and reduced locomotor activity are common hallmarks of ageing. Our study focuses on exploring these phenomena in prematurely ageing PolgA(D257A/D257A) mice (also known as PolgA) aged 41-42 weeks, as they closely mimic human ageing. We assess parameters such as oxygen consumption (VO2), carbon dioxide production (VCO2), respiratory exchange ratio (RER) and locomotor activity using a metabolic cage for 4 days and comparing them with age-matched wild-type littermates (WT). Our findings revealed that VO2, VCO2, RER, locomotor activities, water intake and feeding behaviour show a daily rhythm, aligning with roughly a 24-h cycle. We observed that the RER was significantly increased in PolgA mice compared to WT mice during the night-time of the light-dark cycle, suggesting a shift towards a higher reliance on carbohydrate metabolism due to more food intake during the active phase. Additionally, female PolgA mice displayed a distinct phenotype with reduced walking speed, walking distance, body weight and grip strength in comparison to male PolgA and WT mice, indicating an early sign of ageing. Taken together, our research highlights the impact of sex-specific patterns on ageing traits in PolgA mice aged 41-42 weeks, which may be attributable to human ageing phenotypes. The unique genetic composition and accelerated ageing characteristics of PolgA mice make them invaluable in ageing studies, facilitating the investigation of underlying biological mechanisms and the identification of potential therapeutic targets for age-related diseases.
Collapse
Affiliation(s)
- Amit Singh
- Institute for Biomechanics, ETH Zurich, Switzerland
| | | | - Esther Wehrle
- Institute for Biomechanics, ETH Zurich, Switzerland
- AO Research Institute Davos, Switzerland
| | | | - Ralph Müller
- Institute for Biomechanics, ETH Zurich, Switzerland
| |
Collapse
|
2
|
Dutta P, Layton AT. Sex and circadian regulation of metabolic demands in the rat kidney: A modeling analysis. PLoS One 2024; 19:e0293419. [PMID: 39018272 PMCID: PMC11253979 DOI: 10.1371/journal.pone.0293419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 10/12/2023] [Indexed: 07/19/2024] Open
Abstract
Renal hemodynamics, renal transporter expression levels, and urine excretion exhibit circadian variations. Disruption of these diurnal patterns is associated with the pathophysiology of hypertension and chronic kidney disease. Renal hemodynamics determines oxygen delivery, whereas renal transport and metabolism determines oxygen consumption; the balance between them yields renal oxygenation which also demonstrates 24-h periodicity. Another notable modulator of kidney function is sex, which has impacts on renal hemodynamics and transport function that are regulated by as well as independent of the circadian clock. The goal of this study was to investigate the diurnal and sexual variations in renal oxygen consumption and oxygenation. For this purpose, we developed computational models of rat kidney function that represent sexual dimorphism and circadian variation in renal hemodynamics and transporter activities. Model simulations predicted substantial differences in tubular Na+ transport and oxygen consumption among different nephron segments. We also simulated the effect of loop diuretics, which are used in the treatment of renal hypoxia, on medullary oxygen tension. Our model predicted a significantly higher effect of loop diuretics on medullary oxygenation in female rats compared to male rats and when administered during the active phase.
Collapse
Affiliation(s)
- Pritha Dutta
- Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario, Canada
| | - Anita T. Layton
- Department of Applied Mathematics, University of Waterloo, Waterloo, Ontario, Canada
- Cheriton School of Computer Science, University of Waterloo, Waterloo, Ontario, Canada
- Department of Biology, University of Waterloo, Waterloo, Ontario, Canada
- School of Pharmacy, University of Waterloo, Waterloo, Ontario, Canada
| |
Collapse
|
3
|
Rasmussen CW, Bøgh N, Ringgaard S, Birn H, Vaeggemose M, Schulte RF, Laustsen C. Daytime Variation in Kidney Perfusion, Oxygenation, and Sodium Concentration Assessed by Multiparametric MRI in Healthy Volunteers. J Magn Reson Imaging 2024; 59:1603-1611. [PMID: 37656067 DOI: 10.1002/jmri.28983] [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: 06/16/2023] [Revised: 08/14/2023] [Accepted: 08/15/2023] [Indexed: 09/02/2023] Open
Abstract
BACKGROUND MRI can provide information on kidney structure, perfusion, and oxygenation. Furthermore, it allows for the assessment of kidney sodium concentrations and handling, allowing multiparametric evaluation of kidney physiology. Multiparametric MRI is promising for establishing prognosis and monitoring treatment responses in kidney diseases, but its intraindividual variation during the day is unresolved. PURPOSE To investigate the variation in multiparametric MRI measurements from the morning to the evening. STUDY TYPE Prospective. POPULATION Ten healthy volunteers, aged 29 ± 5 without history of kidney disease. FIELD STRENGTH/SEQUENCE 3 T/T1 mapping, blood-oxygen level dependent imaging, arterial spin labeling perfusion imaging, diffusion weighted imaging, and sodium imaging. ASSESSMENT A multiparametric MRI protocol, yielding T1, R2*, ADC, renal blood flow and renal sodium levels, was acquired in the morning, noon, and evening. The participants were fasting prior to the first examination. Urine biochemical analyses were performed to complement MRI data. The cortex and medulla were analyzed separately in a semi-automatic fashion, and gradients of total sodium concentration (TSC) and R2* gradients were calculated from outer cortex to inner medulla. STATISTICAL TEST Analyses of variance and mixed-effects models to estimate differences from time of day. Coefficients of variation to assess variability within and between participants. A P-value <0.05 was considered statistically significant. RESULTS The coefficients of variation varied from 5% to 18% for proton-based parametric sequences, while it was 38% for TSC over a day. DATA CONCLUSION Multiparametric MRI is stable over the day. The coefficients of variation over a day were lower for proton multiparametric MRI, but higher for sodium MRI. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 2.
Collapse
Affiliation(s)
- Camilla W Rasmussen
- The MR Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Nikolaj Bøgh
- The MR Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Steffen Ringgaard
- The MR Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Henrik Birn
- Department of Renal Medicine, Aarhus University Hospital, Aarhus, Denmark
- Department of Biomedicine, Aarhus University, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Michael Vaeggemose
- The MR Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- GE HealthCare, Broendby, Denmark
| | | | - Christoffer Laustsen
- The MR Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| |
Collapse
|
4
|
Qin S, Ma L, Ferreira F, Brown C, Navedo MF, Reid B, Zhao M. Diabetic Ocular Surface Has Defects in Oxygen Uptake Revealed by Optic Fiber Microsensor. Invest Ophthalmol Vis Sci 2024; 65:27. [PMID: 38506851 PMCID: PMC10959196 DOI: 10.1167/iovs.65.3.27] [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: 11/16/2023] [Accepted: 02/25/2024] [Indexed: 03/21/2024] Open
Abstract
Purpose Diabetes mellitus causes diabetic keratopathy (DK). This and other ocular surface disorders are underdiagnosed and problematic for affected patients as well as recipients of diabetic donor corneas. Thus, it is important to find noninvasive means to facilitate determination of the potentially vision-threatening DK. It has been reported that diabetic corneas uptake significantly less oxygen (O2) than healthy controls. However, an integral assessment of the ocular surface is missing. Methods Using an optic-fiber O2 micro-sensor (optrode) we demonstrated recently that the healthy ocular surface displays a unique spatiotemporal map of O2 consumption. We hypothesize that diabetes impairs the spatiotemporal profile of O2 uptake at the ocular surface. Results Using streptozotocin (STZ)-induced diabetic mice, we found diminished O2 uptake and loss of the unique pattern across the ocular surface. A diabetic cornea consumes significantly less O2 at the bulbar conjunctiva and limbus, but not the central and peripheral cornea, compared to controls. Further, we show that, contrary to the healthy cornea, the diabetic cornea does not increase the O2 consumption at the limbus in the evening as the normal control. Conclusions Altogether, our measurements reveal a previously unknown impairment in O2 uptake at the diabetic cornea, making it a potential tool to diagnose ocular surface abnormalities and suggesting a new etiology mechanism.
Collapse
Affiliation(s)
- Sun Qin
- Department of Dermatology, Institute for Regenerative Cures, School of Medicine, University of California, Davis, California, United States
- School of Life Science, Yunnan Normal University, Yunnan, China
| | - Li Ma
- Department of Dermatology, Institute for Regenerative Cures, School of Medicine, University of California, Davis, California, United States
| | - Fernando Ferreira
- Department of Dermatology, Institute for Regenerative Cures, School of Medicine, University of California, Davis, California, United States
- Departamento de Biologia, Centro de Biologia Molecular e Ambiental (CBMA), Universidade do Minho, Braga, Portugal
| | - Chelsea Brown
- Department of Ophthalmology & Vision Science, Institute for Regenerative Cures, School of Medicine, University of California, Davis, California, United States
| | - Manuel F. Navedo
- Department of Pharmacology, School of Medicine, University of California, Davis, California, United States
| | - Brian Reid
- Department of Dermatology, Institute for Regenerative Cures, School of Medicine, University of California, Davis, California, United States
- Department of Ophthalmology & Vision Science, Institute for Regenerative Cures, School of Medicine, University of California, Davis, California, United States
| | - Min Zhao
- Department of Dermatology, Institute for Regenerative Cures, School of Medicine, University of California, Davis, California, United States
- Department of Ophthalmology & Vision Science, Institute for Regenerative Cures, School of Medicine, University of California, Davis, California, United States
| |
Collapse
|
5
|
Arnaud C, Billoir E, de Melo Junior AF, Pereira SA, O'Halloran KD, Monteiro EC. Chronic intermittent hypoxia-induced cardiovascular and renal dysfunction: from adaptation to maladaptation. J Physiol 2023; 601:5553-5577. [PMID: 37882783 DOI: 10.1113/jp284166] [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: 07/07/2023] [Accepted: 10/12/2023] [Indexed: 10/27/2023] Open
Abstract
Chronic intermittent hypoxia (CIH) is the dominant pathological feature of human obstructive sleep apnoea (OSA), which is highly prevalent and associated with cardiovascular and renal diseases. CIH causes hypertension, centred on sympathetic nervous overactivity, which persists following removal of the CIH stimulus. Molecular mechanisms contributing to CIH-induced hypertension have been carefully delineated. However, there is a dearth of knowledge on the efficacy of interventions to ameliorate high blood pressure in established disease. CIH causes endothelial dysfunction, aberrant structural remodelling of vessels and accelerates atherosclerotic processes. Pro-inflammatory and pro-oxidant pathways converge on disrupted nitric oxide signalling driving vascular dysfunction. In addition, CIH has adverse effects on the myocardium, manifesting atrial fibrillation, and cardiac remodelling progressing to contractile dysfunction. Sympatho-vagal imbalance, oxidative stress, inflammation, dysregulated HIF-1α transcriptional responses and resultant pro-apoptotic ER stress, calcium dysregulation, and mitochondrial dysfunction conspire to drive myocardial injury and failure. CIH elaborates direct and indirect effects in the kidney that initially contribute to the development of hypertension and later to chronic kidney disease. CIH-induced morphological damage of the kidney is dependent on TLR4/NF-κB/NLRP3/caspase-1 inflammasome activation and associated pyroptosis. Emerging potential therapies related to the gut-kidney axis and blockade of aryl hydrocarbon receptors (AhR) are promising. Cardiorenal outcomes in response to intermittent hypoxia present along a continuum from adaptation to maladaptation and are dependent on the intensity and duration of exposure to intermittent hypoxia. This heterogeneity of OSA is relevant to therapeutic treatment options and we argue the need for better stratification of OSA phenotypes.
Collapse
Affiliation(s)
- Claire Arnaud
- Université Grenoble-Alpes INSERM U1300, Laboratoire HP2, Grenoble, France
| | - Emma Billoir
- Université Grenoble-Alpes INSERM U1300, Laboratoire HP2, Grenoble, France
| | | | - Sofia A Pereira
- iNOVA4Health, NOVA Medical School, Universidade NOVA de Lisboa, Lisboa, Portugal
| | - Ken D O'Halloran
- Department of Physiology, School of Medicine, College of Medicine & Health, University College Cork, Cork, Ireland
| | - Emilia C Monteiro
- iNOVA4Health, NOVA Medical School, Universidade NOVA de Lisboa, Lisboa, Portugal
| |
Collapse
|
6
|
Pimpão AB, Sousa C, Correia MJ, Coelho NR, Monteiro EC, Melo Junior AF, Pereira SA. Control of Arterial Hypertension by the AhR Blocker CH-223191: A Chronopharmacological Study in Chronic Intermittent Hypoxia Conditions. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1427:35-42. [PMID: 37322333 DOI: 10.1007/978-3-031-32371-3_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Chronic intermittent hypoxia (CIH) is a major contributor to the development of hypertension (HTN) in obstructive sleep apnea (OSA). OSA subjects frequently display a non-dipping pattern of blood pressure (BP) and resistant HTN. After discovering that AHR-CYP1A1 axis is a druggable target in CIH-HTN, we hypothesized that CH-223191 could control BP in both active and inactive periods of the animals, recovering the BP dipping profile in CIH conditions.We evaluated the chronopharmacology of the antihypertensive efficacy of the AhR blocker CH-223191 in CIH conditions (21% to 5% of O2, 5.6 cycles/h, 10.5 h/day, in inactive period of Wistar rats). BP was measured by radiotelemetry, at 8 am (active phase) and at 6 pm (inactive phase) of the animals. The circadian variation of AhR activation in the kidney in normoxia was also assessed, measuring the CYP1A1 (hallmark of AhR activation) protein levels.Despite drug administration before starting the inactive period of the animals, CH-223191 was not able to decrease BP during the inactive phase, in CIH conditions, therefore not reverting the non-dipping profile. These results suggest that a higher dose or different time of administration of CH-223191 might be needed for an antihypertensive effect throughout the 24-h cycle.
Collapse
Affiliation(s)
- António B Pimpão
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Cátia Sousa
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Maria J Correia
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Nuno R Coelho
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisboa, Portugal
- Egas Moniz Center for Interdisciplinary Research, Egas Moniz School of Health and Science, Caparica, Portugal
| | - Emília C Monteiro
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Antonio F Melo Junior
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisboa, Portugal
| | - Sofia A Pereira
- iNOVA4Health, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, Lisboa, Portugal.
| |
Collapse
|
7
|
Liu W, Zhao D, Wu X, Yue F, Yang H, Hu K. Rapamycin ameliorates chronic intermittent hypoxia and sleep deprivation-induced renal damage via the mammalian target of rapamycin (mTOR)/NOD-like receptor protein 3 (NLRP3) signaling pathway. Bioengineered 2022; 13:5537-5550. [PMID: 35184679 PMCID: PMC8973698 DOI: 10.1080/21655979.2022.2037872] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Rapamycin inhibits the activation of NOD-like receptor protein 3 (NLRP3) by regulating the mammalian target of rapamycin (mTOR) to treat obstructive sleep apnea-related renal injury. Sleep deprivation (SD) and chronic intermittent hypoxia (CIH) mouse models were used to assess the effects of autophagy in vivo. Compared with the control, SD, and CIH groups, the SD+CIH group had lower body weight and higher levels of blood urea nitrogen (BUN), creatinine, and urinary albumin (U-Alb) (P < 0.05); renal injury and oxidative damage occurred in the SD+CIH group, the kidney cell nucleus ruptured, and morphological structure of the cells was unclear in the SD+CIH group. The SD+CIH group demonstrated increased apoptosis compared with the control, SD, and CIH groups using Western blot analysis. Compared to the control, SD, and CIH groups, the SD+CIH group showed a higher degree of microtubule-associated protein light chain 3\ staining. Compared to the SD+CIH group, BUN, creatinine, and U-Alb levels decreased, and apoptosis increased in the SD+CIH+rapamycin group, and the structure of the kidney after rapamycin treatment was well preserved. The mTOR expression was increased in the kidneys of the SD+CIH group. The NLRP3, Gasdermin D (GMDSD), interleukin (IL)-18, IL-1β, and cleaved-caspase-1 protein levels were higher in the SD+CIH group than the SD+CIH+rapamycin group, and the NLRP3, GMDSD, IL-18, IL-1β, and cleaved-caspase-1 mRNA levels were higher in the SD+CIH group than the SD+CIH+rapamycin group. Following rapamycin treatment, pyroptosis was suppressed. Rapamycin ameliorates renal damage by inhibiting the mTOR/NLRP3 signaling pathway.
Collapse
Affiliation(s)
- Wei Liu
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Dong Zhao
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Xiaofeng Wu
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Fang Yue
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Haizhen Yang
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Ke Hu
- Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| |
Collapse
|
8
|
Akhtar MS, Rehman AU, Arshad H, Malik A, Fatima M, Tabassum T, Raza AR, Bukhsh M, Murtaza MA, Mehmood MH, Sultan A, Rasool G, Riaz M. In Vitro Antioxidant Activities and the Therapeutic Potential of Some Newly Synthesized Chalcones Against 4-Acetaminophenol Induced Hepatotoxicity in Rats. Dose Response 2021; 19:1559325821996955. [PMID: 33795997 PMCID: PMC7968038 DOI: 10.1177/1559325821996955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/23/2021] [Accepted: 01/25/2021] [Indexed: 01/14/2023] Open
Abstract
The lack of safety and efficacy of existing hepatoprotective agents urge the need to explore novel hepatoprotective agents. The research work was planned to study the therapeutic potential of some newly synthesized chalcones against 4-acetaminophenol induced hepatotoxicity in rats. Male albino rats (N = 30) were divided into 6 groups of 5 animals each i.e. group I; Toxic control (4-acetaminophenol), group II; normal control (Normal saline), group III; Positive control (silymarin; 50 mg/kg bw) and groups IV-VI (test groups) treated with 3 chalcone analogues i-e 3a, 3f & 3 g (100, 150, 150 mg/kg bw, respectively). All the study group animals were administered with 4-acetaminophenol to induce hepatotoxicity except normal control. Following hepatotoxicity induction, test group animals were administered with selected doses of test compounds and toxic group animals left untreated. Liver enzymes including ALT, AST, ALP and serum bilirubin were determined photometrically. Antioxidant activities of test compounds were also determined. Histopathological examination of liver biopsies was also carried out through H & E staining. The test chalcones (3a, 3f & 3 g) significantly decreased the levels of liver enzymes and serum bilirubin toward normal and the pattern of results in the test group animals were comparable to silymarin administered animals indicating the hepatoprotective potential of test compounds. Moreover, the test chalcones (3a, 3f & 3 g) antagonized the effect of 4-acetaminophenol and thus, raised the catalase (CAT) and superoxide dismutase (SOD) while decreased the malondialdehyde (MDA) in experimental animals. The test chalcones (3a, 3f & 3 g) on histological examination of liver showed improvement of tissue morphology. The study concluded that the tested compounds have antioxidant potential and may act as hepatoprotective agent. However, in-depth studies are required to validate their safety and to elucidate the exact mechanism of action.
Collapse
Affiliation(s)
- Muhammad Shoaib Akhtar
- Department of Pharmacology, College of Pharmacy, University of Sargodha, Sargodha, Pakistan
| | - Aziz-Ur- Rehman
- Department of Pathobiology, College of Veterinary and Animal Sciences (Jhang Campus), University of Veterinary and Animal Sciences, Lahore, Pakistan
| | - Haroon Arshad
- Health Department, Government of the Punjab, Lahore, Pakistan
| | - Abdul Malik
- Department of Pharmacology, College of Pharmacy, University of Sargodha, Sargodha, Pakistan
| | - Muheer Fatima
- Department of Pharmacology, College of Pharmacy, University of Sargodha, Sargodha, Pakistan
| | - Tahira Tabassum
- Department of Pathology, Sargodha Medical College, University of Sargodha, Sargodha, Pakistan
| | - Abdul Rauf Raza
- Ibn-e-Sina Block, Department of Chemistry, University of Sargodha, Sargodha, Pakistan
| | - Munnaza Bukhsh
- Foundation University Medical College, Islamabad, Pakistan
| | - Mian Anjum Murtaza
- Institute of Food Science and Nutrition, University of Sargodha, Sargodha, Pakistan
| | - Malik Hassan Mehmood
- Department of Pharmacology, Faculty of Pharmaceutical Sciences, Government College University, Faisalabad, Pakistan
| | - Ayesha Sultan
- Department of Chemistry, University of Education, Faisalabad Campus, Faisalabad, Pakistan
| | - Ghulam Rasool
- Department of Allied Health Sciences, Sargodha Medical College, University of Sargodha, Sargodha, Pakistan
| | - Muhammad Riaz
- Department of Allied Health Sciences, Sargodha Medical College, University of Sargodha, Sargodha, Pakistan
| |
Collapse
|
9
|
Eckerbom P, Hansell P, Cox E, Buchanan C, Weis J, Palm F, Francis S, Liss P. Circadian variation in renal blood flow and kidney function in healthy volunteers monitored with noninvasive magnetic resonance imaging. Am J Physiol Renal Physiol 2020; 319:F966-F978. [PMID: 33073586 DOI: 10.1152/ajprenal.00311.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Circadian regulation of kidney function is involved in maintaining whole body homeostasis, and dysfunctional circadian rhythm can potentially be involved in disease development. Magnetic resonance imaging (MRI) provides reliable and reproducible repetitive estimates of kidney function noninvasively without the risk of adverse events associated with contrast agents and ionizing radiation. The purpose of this study was to estimate circadian variations in kidney function in healthy human subjects with MRI and to relate the findings to urinary excretions of electrolytes and markers of kidney function. Phase-contrast imaging, arterial spin labeling, and blood oxygen level-dependent transverse relaxation rate (R2*) mapping were used to assess total renal blood flow and regional perfusion as well as intrarenal oxygenation in eight female and eight male healthy volunteers every fourth hour during a 24-h period. Parallel with MRI scans, standard urinary and plasma parameters were quantified. Significant circadian variations of total renal blood flow were found over 24 h, with increasing flow from noon to midnight and decreasing flow during the night. In contrast, no circadian variation in intrarenal oxygenation was detected. Urinary excretions of electrolytes, osmotically active particles, creatinine, and urea all displayed circadian variations, peaking during the afternoon and evening hours. In conclusion, total renal blood flow and kidney function, as estimated from excretion of electrolytes and waste products, display profound circadian variations, whereas intrarenal oxygenation displays significantly less circadian variation.
Collapse
Affiliation(s)
- Per Eckerbom
- Section of Radiology, Department of Surgical Sciences, University Hospital, Uppsala, Sweden
| | - Peter Hansell
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Eleanor Cox
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom
| | - Charlotte Buchanan
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom
| | - Jan Weis
- Department of Medical Physics, Uppsala University Hospital, Uppsala, Sweden
| | - Fredrik Palm
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Susan Francis
- Sir Peter Mansfield Imaging Centre, University of Nottingham, Nottingham, United Kingdom
| | - Per Liss
- Section of Radiology, Department of Surgical Sciences, University Hospital, Uppsala, Sweden
| |
Collapse
|
10
|
Abstract
Humans, like all mammals, partition their daily behaviour into activity (wakefulness) and rest (sleep) phases that differ largely in their metabolic requirements. The circadian clock evolved as an autonomous timekeeping system that aligns behavioural patterns with the solar day and supports the body functions by anticipating and coordinating the required metabolic programmes. The key component of this synchronization is a master clock in the brain, which responds to light-darkness cues from the environment. However, to achieve circadian control of the entire organism, each cell of the body is equipped with its own circadian oscillator that is controlled by the master clock and confers rhythmicity to individual cells and organs through the control of rate-limiting steps of metabolic programmes. Importantly, metabolic regulation is not a mere output function of the circadian system, but nutrient, energy and redox levels signal back to cellular clocks in order to reinforce circadian rhythmicity and to adapt physiology to temporal tissue-specific needs. Thus, multiple systemic and molecular mechanisms exist that connect the circadian clock with metabolism at all levels, from cellular organelles to the whole organism, and deregulation of this circadian-metabolic crosstalk can lead to various pathologies.
Collapse
|
11
|
Joles JA. Measuring systolic and diastolic blood pressure in rodents. Kidney Int 2019; 96:1424-1425. [PMID: 31759491 DOI: 10.1016/j.kint.2019.09.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 09/11/2019] [Indexed: 11/16/2022]
Affiliation(s)
- Jaap A Joles
- Department of Nephrology and Hypertension, University Medical Center Utrecht, Utrecht, The Netherlands.
| |
Collapse
|
12
|
Abstract
Numerous physiological functions exhibit substantial circadian oscillations. In the kidneys, renal plasma flow, the glomerular filtration rate and tubular reabsorption and/or secretion processes have been shown to peak during the active phase and decline during the inactive phase. These functional rhythms are driven, at least in part, by a self-sustaining cellular mechanism termed the circadian clock. The circadian clock controls different cellular functions, including transcription, translation and protein post-translational modifications (such as phosphorylation, acetylation and ubiquitylation) and degradation. Disruption of the circadian clock in animal models results in the loss of blood pressure control and substantial changes in the circadian pattern of water and electrolyte excretion in the urine. Kidney-specific suppression of the circadian clock in animals implicates both the intrinsic renal and the extrarenal circadian clocks in these pathologies. Alterations in the circadian rhythm of renal functions are associated with the development of hypertension, chronic kidney disease, renal fibrosis and kidney stones. Furthermore, renal circadian clocks might interfere with the pharmacokinetics and/or pharmacodynamics of various drugs and are therefore an important consideration in the treatment of some renal diseases or disorders.
Collapse
Affiliation(s)
- Dmitri Firsov
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland.
| | - Olivier Bonny
- Department of Pharmacology and Toxicology, University of Lausanne, Lausanne, Switzerland. .,Service of Nephrology, Department of Medicine, Lausanne University Hospital, Lausanne, Switzerland.
| |
Collapse
|
13
|
Adamovich Y, Ladeuix B, Sobel J, Manella G, Neufeld-Cohen A, Assadi MH, Golik M, Kuperman Y, Tarasiuk A, Koeners MP, Asher G. Oxygen and Carbon Dioxide Rhythms Are Circadian Clock Controlled and Differentially Directed by Behavioral Signals. Cell Metab 2019; 29:1092-1103.e3. [PMID: 30773466 DOI: 10.1016/j.cmet.2019.01.007] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 11/13/2018] [Accepted: 01/16/2019] [Indexed: 12/25/2022]
Abstract
Daily rhythms in animal physiology are driven by endogenous circadian clocks in part through rest-activity and feeding-fasting cycles. Here, we examined principles that govern daily respiration. We monitored oxygen consumption and carbon dioxide release, as well as tissue oxygenation in freely moving animals to specifically dissect the role of circadian clocks and feeding time on daily respiration. We found that daily rhythms in oxygen and carbon dioxide are clock controlled and that time-restricted feeding restores their rhythmicity in clock-deficient mice. Remarkably, day-time feeding dissociated oxygen rhythms from carbon dioxide oscillations, whereby oxygen followed activity, and carbon dioxide was shifted and aligned with food intake. In addition, changes in carbon dioxide levels altered clock gene expression and phase shifted the clock. Collectively, our findings indicate that oxygen and carbon dioxide rhythms are clock controlled and feeding regulated and support a potential role for carbon dioxide in phase resetting peripheral clocks upon feeding.
Collapse
Affiliation(s)
- Yaarit Adamovich
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Benjamin Ladeuix
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Jonathan Sobel
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Gal Manella
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Adi Neufeld-Cohen
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Mohammad H Assadi
- Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Marina Golik
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Yael Kuperman
- Department of Veterinary Resources, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Ariel Tarasiuk
- Sleep-Wake Disorders Unit, Soroka University Medical Center, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel; Department of Physiology and Cell Biology, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Maarten P Koeners
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, University of Exeter, Exeter, UK
| | - Gad Asher
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel.
| |
Collapse
|
14
|
Lin X, Liu Y, Meng T, Xie C, Wu X, Yin Y. Circadian calcium feeding regime in laying hens related to zinc concentration, gene expression of circadian clock, calcium transporters and oxidative status. J Trace Elem Med Biol 2018; 50:518-526. [PMID: 29548611 DOI: 10.1016/j.jtemb.2018.03.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 02/03/2018] [Accepted: 03/05/2018] [Indexed: 02/07/2023]
Abstract
The study was conducted to investigate the effects of different circadian calcium feeding regimes on parameters of Zn status and gene expression of circadian clock, calcium transporters and oxidative status in laying hens. In total, 180 of 41-weeks Brown Hy-line laying hens were assigned randomly into three groups, 1-CON group (Control Ca, diets contained 3.4% Ca at both 0730 and 1530 h), 2-HL group (High-low Ca, diets contained 3.6%-3.2% Ca respectively) and 3-LH group (Low-high Ca, diets contained 3.2%-3.6% Ca respectively), which were fed a certain amount of control diet at 0730 h and 1530 h. Blood, tibia, jejunum and kidney samples were collected at 4 h intervals with initial starting at 0800 h after 10 weeks of experiment. Compared with the CON group: 1) the serum zinc in HL group increased at 2000 h, but lower at 1600 h in LH group (P < 0.05). 2) in jejunum, circadian clock genes including CLOCK and BMAL1 expression of HL group were down-regulated at 0000 h and 1600 h, as well as CLOCK, BMAL1, Cry2, Per3 and calcium transporter gene NCX1 in LH group at 2000 h (P < 0.05). 3) in kidney, CLOCK, Cry1, Cry2 and Per3 of LH group were up-regulated at 0400 h, CLOCK at 0000 h as well, while CLOCK at 2000 h were down-regulated (P < 0.05). 4) in kidney, the calcium transporters including PMCA, CaBP and CA of LH group were up-regulated at 0000 h, but PMCA and CaBP of LH group were down-regulated at 0800 h, 1200 h and 1600 h, as well as CA at 1600 h and PMCA at 2000 h of LH group (P < 0.05), and the oxidative gene SOD of the LH group was up-regulated at 0400 h, as well as CAT at 0400 h, SOD and GPX1 at 1200 h in HL group, but SOD at 1600 h and 2000 h, and GPX1 at 1600 h were down-regulated in LH group (P < 0.05). These results demonstrated that the dynamic circadian calcium feeding regime affected circadian rhythms of serum zinc concentration as well as the expression of certain genes related to the circadian clock, calcium transport and antioxidative capacity, and circadian calcium feeding regimes may therefore be considered with regard to improving the calcium usability.
Collapse
Affiliation(s)
- Xue Lin
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China; Hunan Co-Innovation Center of Safety Animal Production, College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Yilin Liu
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China
| | - Tiantian Meng
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China; Hunan Co-Innovation Center of Safety Animal Production, College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Chunyan Xie
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China
| | - Xin Wu
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China; Hunan Co-Innovation Center of Safety Animal Production, College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China.
| | - Yulong Yin
- Key Laboratory of Agro-ecological Processes in Subtropical Region, Institute of Subtropical Agriculture, The Chinese Academy of Sciences, National Engineering Laboratory for Pollution Control and Waste Utilization in Livestock and Poultry Production, Hunan Provincial Engineering Research Center for Healthy Livestock and Poultry Production, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Changsha 410125, China; Hunan Co-Innovation Center of Safety Animal Production, College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| |
Collapse
|
15
|
Angiotensin II-induced hypertension in rats is only transiently accompanied by lower renal oxygenation. Sci Rep 2018; 8:16342. [PMID: 30397212 PMCID: PMC6218546 DOI: 10.1038/s41598-018-34211-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 10/09/2018] [Indexed: 02/08/2023] Open
Abstract
Activation of the renin-angiotensin system may initiate chronic kidney disease. We hypothesised that renal hypoxia is a consequence of hemodynamic changes induced by angiotensin II and occurs prior to development of severe renal damage. Male Sprague-Dawley rats were infused continuously with angiotensin II (350 ng/kg/min) for 8 days. Mean arterial pressure (n = 5), cortical (n = 6) and medullary (n = 7) oxygenation (pO2) were continuously recorded by telemetry and renal tissue injury was scored. Angiotensin II increased arterial pressure gradually to 150 ± 18 mmHg. This was associated with transient reduction of oxygen levels in renal cortex (by 18 ± 2%) and medulla (by 17 ± 6%) at 10 ± 2 and 6 ± 1 hours, respectively after starting infusion. Thereafter oxygen levels normalised to pre-infusion levels and were maintained during the remainder of the infusion period. In rats receiving angiotensin II, adding losartan to drinking water (300 mg/L) only induced transient increase in renal oxygenation, despite normalisation of arterial pressure. In rats, renal hypoxia is only a transient phenomenon during initiation of angiotensin II-induced hypertension.
Collapse
|
16
|
Emans TW, Janssen BJ, Joles JA, Krediet CP. Nitric Oxide Synthase Inhibition Induces Renal Medullary Hypoxia in Conscious Rats. J Am Heart Assoc 2018; 7:e009501. [PMID: 30371226 PMCID: PMC6201463 DOI: 10.1161/jaha.118.009501] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 06/18/2018] [Indexed: 12/14/2022]
Abstract
Background Renal hypoxia, implicated as crucial factor in onset and progression of chronic kidney disease, may be attributed to reduced nitric oxide because nitric oxide dilates vasculature and inhibits mitochondrial oxygen consumption. We hypothesized that chronic nitric oxide synthase inhibition would induce renal hypoxia. Methods and Results Oxygen-sensitive electrodes, attached to telemeters, were implanted in either renal cortex (n=6) or medulla (n=7) in rats. After recovery and stabilization, baseline oxygenation ( pO 2) was recorded for 1 week. To inhibit nitric oxide synthase, N-ω-nitro-l-arginine (L-NNA; 40 mg/kg/day) was administered via drinking water for 2 weeks. A separate group (n=8), instrumented with blood pressure telemeters, followed the same protocol. L-NNA rapidly induced hypertension (165±6 versus 108±3 mm Hg; P<0.001) and proteinuria (79±12 versus 17±2 mg/day; P<0.001). Cortical pO 2, after initially dipping, returned to baseline and then increased. Medullary pO 2 decreased progressively (up to -19±6% versus baseline; P<0.05). After 14 days of L-NNA, amplitude of diurnal medullary pO 2 was decreased (3.7 [2.2-5.3] versus 7.9 [7.5-8.4]; P<0.01), whereas amplitudes of blood pressure and cortical pO 2 were unaltered. Terminal glomerular filtration rate (1374±74 versus 2098±122 μL/min), renal blood flow (5014±336 versus 9966±905 μL/min), and sodium reabsorption efficiency (13.0±0.8 versus 22.8±1.7 μmol/μmol) decreased (all P<0.001). Conclusions For the first time, we show temporal development of renal cortical and medullary oxygenation during chronic nitric oxide synthase inhibition in unrestrained conscious rats. Whereas cortical pO 2 shows transient changes, medullary pO 2 decreased progressively. Chronic L-NNA leads to decreased renal perfusion and sodium reabsorption efficiency, resulting in progressive medullary hypoxia, suggesting that juxtamedullary nephrons are potentially vulnerable to prolonged nitric oxide depletion.
Collapse
Affiliation(s)
- Tonja W. Emans
- Internal Medicine‐NephrologyAmsterdam UMC / Academic Medical Centre at the University of AmsterdamThe Netherlands
- Nephrology and HypertensionUniversity Medical Centre UtrechtThe Netherlands
| | - Ben J. Janssen
- Pharmacology and ToxicologyMaastricht UniversityThe Netherlands
| | - Jaap A. Joles
- Nephrology and HypertensionUniversity Medical Centre UtrechtThe Netherlands
| | - C.T. Paul Krediet
- Internal Medicine‐NephrologyAmsterdam UMC / Academic Medical Centre at the University of AmsterdamThe Netherlands
| |
Collapse
|
17
|
Crislip GR, Masten SH, Gumz ML. RECENT ADVANCES IN UNDERSTANDING THE CIRCADIAN CLOCK IN RENAL PHYSIOLOGY. CURRENT OPINION IN PHYSIOLOGY 2018; 5:38-44. [PMID: 30714020 DOI: 10.1016/j.cophys.2018.06.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Accumulating evidence suggests a critical role for the molecular circadian clock in the regulation of renal function. Here, we consider the most recent advances in our understanding of the relationship between the circadian clock and renal physiology.
Collapse
Affiliation(s)
- G Ryan Crislip
- Department of Medicine, Division of Nephrology, Hypertension, and Renal Transplantation.,Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL 32610
| | - Sarah H Masten
- Department of Medicine, Division of Nephrology, Hypertension, and Renal Transplantation
| | - Michelle L Gumz
- Department of Medicine, Division of Nephrology, Hypertension, and Renal Transplantation.,Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL 32610
| |
Collapse
|
18
|
Patinha D, Pijacka W, Paton JFR, Koeners MP. Cooperative Oxygen Sensing by the Kidney and Carotid Body in Blood Pressure Control. Front Physiol 2017; 8:752. [PMID: 29046642 PMCID: PMC5632678 DOI: 10.3389/fphys.2017.00752] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 09/15/2017] [Indexed: 12/13/2022] Open
Abstract
Oxygen sensing mechanisms are vital for homeostasis and survival. When oxygen levels are too low (hypoxia), blood flow has to be increased, metabolism reduced, or a combination of both, to counteract tissue damage. These adjustments are regulated by local, humoral, or neural reflex mechanisms. The kidney and the carotid body are both directly sensitive to falls in the partial pressure of oxygen and trigger reflex adjustments and thus act as oxygen sensors. We hypothesize a cooperative oxygen sensing function by both the kidney and carotid body to ensure maintenance of whole body blood flow and tissue oxygen homeostasis. Under pathological conditions of severe or prolonged tissue hypoxia, these sensors may become continuously excessively activated and increase perfusion pressure chronically. Consequently, persistence of their activity could become a driver for the development of hypertension and cardiovascular disease. Hypoxia-mediated renal and carotid body afferent signaling triggers unrestrained activation of the renin angiotensin-aldosterone system (RAAS). Renal and carotid body mediated responses in arterial pressure appear to be synergistic as interruption of either afferent source has a summative effect of reducing blood pressure in renovascular hypertension. We discuss that this cooperative oxygen sensing system can activate/sensitize their own afferent transduction mechanisms via interactions between the RAAS, hypoxia inducible factor and erythropoiesis pathways. This joint mechanism supports our view point that the development of cardiovascular disease involves afferent nerve activation.
Collapse
Affiliation(s)
- Daniela Patinha
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences, University of Bristol, Bristol, United Kingdom.,Institute of Biomedical and Clinical Science, University of Exeter Medical School, University of Exeter, Exeter, United Kingdom
| | - Wioletta Pijacka
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences, University of Bristol, Bristol, United Kingdom
| | - Julian F R Paton
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences, University of Bristol, Bristol, United Kingdom
| | - Maarten P Koeners
- School of Physiology, Pharmacology and Neuroscience, Biomedical Sciences, University of Bristol, Bristol, United Kingdom.,Institute of Biomedical and Clinical Science, University of Exeter Medical School, University of Exeter, Exeter, United Kingdom
| |
Collapse
|