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Okyar A, Ozturk Civelek D, Akyel YK, Surme S, Pala Kara Z, Kavakli IH. The role of the circadian timing system on drug metabolism and detoxification: an update. Expert Opin Drug Metab Toxicol 2024; 20:503-517. [PMID: 38753451 DOI: 10.1080/17425255.2024.2356167] [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: 11/17/2023] [Accepted: 05/13/2024] [Indexed: 05/18/2024]
Abstract
INTRODUCTION The 24-hour variations in drug absorption, distribution, metabolism, and elimination, collectively known as pharmacokinetics, are fundamentally influenced by rhythmic physiological processes regulated by the molecular clock. Recent advances have elucidated the intricacies of the circadian timing system and the molecular interplay between biological clocks, enzymes and transporters in preclinical level. AREA COVERED Circadian rhythm of the drug metabolizing enzymes and carrier efflux functions possess a major role for drug metabolism and detoxification. The efflux and metabolism function of intestines and liver seems important. The investigations revealed that the ABC and SLC transporter families, along with cytochrome p-450 systems in the intestine, liver, and kidney, play a dominant role in the circadian detoxification of drugs. Additionally, the circadian control of efflux by the blood-brain barrier is also discussed. EXPERT OPINION The influence of the circadian timing system on drug pharmacokinetics significantly impacts the efficacy, adverse effects, and toxicity profiles of various drugs. Moreover, the emergence of sex-related circadian changes in the metabolism and detoxification processes has underscored the importance of considering gender-specific differences in drug tolerability and pharmacology. A better understanding of coupling between central clock and circadian metabolism/transport contributes to the development of more rational drug utilization and the implementation of chronotherapy applications.
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Affiliation(s)
- Alper Okyar
- Department of Pharmacology, Istanbul University Faculty of Pharmacy, Istanbul, Turkiye
| | - Dilek Ozturk Civelek
- Department of Pharmacology, Faculty of Pharmacy, Bezmialem Vakif University, Istanbul, Turkiye
| | - Yasemin Kubra Akyel
- Department of Medical Pharmacology, School of Medicine, Istanbul Medipol University, Istanbul, Turkey
- Department of Biochemistry and Biophysics, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Saliha Surme
- Molecular Biology and Genetics, Koc University, Istanbul, Türkiye
- Chemical and Biological Engineering, Koc University, Istanbul, Türkiye
| | - Zeliha Pala Kara
- Department of Pharmacology, Istanbul University Faculty of Pharmacy, Istanbul, Turkiye
| | - I Halil Kavakli
- Molecular Biology and Genetics, Koc University, Istanbul, Türkiye
- Chemical and Biological Engineering, Koc University, Istanbul, Türkiye
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2
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Lal H, Verma SK, Wang Y, Xie M, Young ME. Circadian Rhythms in Cardiovascular Metabolism. Circ Res 2024; 134:635-658. [PMID: 38484029 PMCID: PMC10947116 DOI: 10.1161/circresaha.123.323520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Accepted: 01/23/2024] [Indexed: 03/19/2024]
Abstract
Energetic demand and nutrient supply fluctuate as a function of time-of-day, in alignment with sleep-wake and fasting-feeding cycles. These daily rhythms are mirrored by 24-hour oscillations in numerous cardiovascular functional parameters, including blood pressure, heart rate, and myocardial contractility. It is, therefore, not surprising that metabolic processes also fluctuate over the course of the day, to ensure temporal needs for ATP, building blocks, and metabolism-based signaling molecules are met. What has become increasingly clear is that in addition to classic signal-response coupling (termed reactionary mechanisms), cardiovascular-relevant cells use autonomous circadian clocks to temporally orchestrate metabolic pathways in preparation for predicted stimuli/stresses (termed anticipatory mechanisms). Here, we review current knowledge regarding circadian regulation of metabolism, how metabolic rhythms are synchronized with cardiovascular function, and whether circadian misalignment/disruption of metabolic processes contribute toward the pathogenesis of cardiovascular disease.
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Affiliation(s)
- Hind Lal
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Suresh Kumar Verma
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Yajing Wang
- Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Min Xie
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Martin E. Young
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
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3
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Shen Z, Hou Y, Zhao G, Tan L, Chen J, Dong Z, Ni C, Pei L. Physiological functions of glucose transporter-2: From cell physiology to links with diabetes mellitus. Heliyon 2024; 10:e25459. [PMID: 38333863 PMCID: PMC10850595 DOI: 10.1016/j.heliyon.2024.e25459] [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: 07/24/2023] [Revised: 01/26/2024] [Accepted: 01/26/2024] [Indexed: 02/10/2024] Open
Abstract
Glucose is a sugar crucial for human health since it participates in many biochemical reactions. It produces adenosine 5'-triphosphate (ATP) and nucleosides through glucose metabolic and pentose phosphate pathways. These processes require many transporter proteins to assist in transferring glucose across cells, and the most notable ones are glucose transporter-2 (GLUT-2) and sodium/glucose cotransporter 1 (SGLT1). Glucose enters small intestinal epithelial cells from the intestinal lumen by crossing the brush boundary membrane via the SGLT1 cotransporter. It exits the cells by traversing the basolateral membrane through the activity of the GLUT-2 transporter, supplying energy throughout the body. Dysregulation of these glucose transporters is involved in the pathogenesis of several metabolic diseases, such as diabetes. Natural loss of GLUT-2 or its downregulation causes abnormal blood glucose concentrations in the body, such as fasting hypoglycemia and glucose tolerance. Therefore, understanding GLUT-2 physiology is necessary for exploring the mechanisms of diabetes and targeted treatment development. This article reviews how the apical GLUT-2 transporter maintains normal physiological functions of the human body and the adaptive changes this transporter produces under pathological conditions such as diabetes.
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Affiliation(s)
- Zhean Shen
- Xinjiang Institute of Technology, Aksu, China
| | - Yingze Hou
- Sanquan College of Xinxiang Medical University, Xinxiang, China
| | - Guo Zhao
- National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Libi Tan
- School of Laboratory Medicine and Biotechnology, Southern Medical University, China
| | - Jili Chen
- Department of Nutrition and Food Hygiene School of Public Health, Zhejiang University School of Medicine, Hangzhou, China
| | - Ziqi Dong
- School of Public Health, Peking University Health Science Center, Beijing 100021, China
| | - Chunxiao Ni
- Hangzhou Lin ‘an District Center for Disease Control and Prevention, Hangzhou, China
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Burclaff J. Transcriptional regulation of metabolism in the intestinal epithelium. Am J Physiol Gastrointest Liver Physiol 2023; 325:G501-G507. [PMID: 37786942 PMCID: PMC10894668 DOI: 10.1152/ajpgi.00147.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/20/2023] [Accepted: 09/25/2023] [Indexed: 10/04/2023]
Abstract
Epithelial metabolism in the intestine is increasingly known to be important for stem cell maintenance and activity while also affecting weight gain and diseases. This review compiles studies from recent years which describe major transcription factors controlling metabolic activity across the intestinal epithelium as well as transcriptional and epigenetic networks controlling the factors themselves. Recent studies show that transcriptional regulators serve as the link between signals from the microbiota and diet and epithelial metabolism. Studies have advanced this paradigm to identify druggable targets to block weight gain or disease progression in mice. As such, there is great potential that a better understanding of these regulatory networks will improve our knowledge of intestinal physiology and promote discoveries to benefit human health.
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Affiliation(s)
- Joseph Burclaff
- Joint Department of Biomedical Engineering, University of North Carolina at Chapel Hill and North Carolina State University, Chapel Hill, North Carolina, United States
- Center for Gastrointestinal Biology and Disease, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, North Carolina, United States
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Overduin TS, Wardill HR, Young RL, Page AJ, Gatford KL. Active glucose transport varies by small intestinal region and oestrous cycle stage in mice. Exp Physiol 2023; 108:865-873. [PMID: 37022128 PMCID: PMC10988461 DOI: 10.1113/ep091040] [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: 11/23/2022] [Accepted: 02/28/2023] [Indexed: 04/07/2023]
Abstract
NEW FINDINGS What is the central question of this study? Body mass and food intake change during the female ovarian cycle: does glucose transport by the small intestine also vary? What is the main finding and its importance? We have optimised Ussing chamber methodology to measure region-specific active glucose transport in the small intestine of adult C57BL/6 mice. Our study provides the first evidence that jejunal active glucose transport changes during the oestrous cycle in mice, and is higher at pro-oestrus than oestrus. These results demonstrate adaptation in active glucose uptake, concurrent with previously reported changes in food intake. ABSTRACT Food intake changes across the ovarian cycle in rodents and humans, with a nadir during the pre-ovulatory phase and a peak during the luteal phase. However, it is unknown whether the rate of intestinal glucose absorption also changes. We therefore mounted small intestinal sections from C57BL/6 female mice (8-9 weeks old) in Ussing chambers and measured active ex vivo glucose transport via the change in short-circuit current (∆Isc ) induced by glucose. Tissue viability was confirmed by a positive ∆Isc response to 100 µM carbachol following each experiment. Active glucose transport, assessed after addition of 5, 10, 25 or 45 mM d-glucose to the mucosal chamber, was highest at 45 mM glucose in the distal jejunum compared to duodenum and ileum (P < 0.01). Incubation with the sodium-glucose cotransporter 1 (SGLT1) inhibitor phlorizin reduced active glucose transport in a dose-dependent manner in all regions (P < 0.01). Active glucose uptake induced by addition of 45 mM glucose to the mucosal chamber in the absence or presence of phlorizin was assessed in jejunum at each oestrous cycle stage (n = 9-10 mice per stage). Overall, active glucose uptake was lower at oestrus compared to pro-oestrus (P = 0.025). This study establishes an ex vivo method to measure region-specific glucose transport in the mouse small intestine. Our results provide the first direct evidence that SGLT1-mediated glucose transport in the jejunum changes across the ovarian cycle. The mechanisms underlying these adaptations in nutrient absorption remain to be elucidated.
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Affiliation(s)
- T. Sebastian Overduin
- School of BiomedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Robinson Research InstituteUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Lifelong Health ThemeSouth Australian Health and Medical Research InstituteAdelaideSouth AustraliaAustralia
| | - Hannah R. Wardill
- School of BiomedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Precision Medicine ThemeSouth Australian Health and Medical Research InstituteAdelaideSouth AustraliaAustralia
| | - Richard L. Young
- Lifelong Health ThemeSouth Australian Health and Medical Research InstituteAdelaideSouth AustraliaAustralia
- Adelaide Medical SchoolUniversity of AdelaideAdelaideSouth AustraliaAustralia
| | - Amanda J. Page
- School of BiomedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Lifelong Health ThemeSouth Australian Health and Medical Research InstituteAdelaideSouth AustraliaAustralia
| | - Kathryn L. Gatford
- School of BiomedicineUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Robinson Research InstituteUniversity of AdelaideAdelaideSouth AustraliaAustralia
- Lifelong Health ThemeSouth Australian Health and Medical Research InstituteAdelaideSouth AustraliaAustralia
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Shimada M, Shirouchi B, Kobayashi Y, Higuchi M, Okumura M, Nakagawa T, Hayakawa T. Treatment with Interleukin-25 Suppresses Short-Term High-Fructose Diet-Induced Hepatic Gene Expression and Activities of Fatty Acid Synthesis Enzymes in Rats. J Oleo Sci 2023; 72:99-104. [PMID: 36624060 DOI: 10.5650/jos.ess22266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
This study aimed to investigate the effects of interleukin-25, which belongs to the interleukin-17 family, on short-term high-fructose diet-induced hepatic triacylglycerol accumulation. Rats were fed a high-starch (control) or high-fructose diet for 7 d, with or without intraperitoneal administration of recombinant interleukin-25 from days 3-7. Treatment with interleukin-25 significantly reduced the mRNA levels and activity of fatty acid synthesis enzymes and caused a nominal reduction in hepatic triacylglycerol levels in rats fed a high-fructose diet but not in those fed a control diet. Interleukin-25 treatment did not affect the mRNA levels of β-oxidation enzymes in either the control or fructose-fed rats. These results suggest that treatment with interleukin-25 suppresses short-term high-fructose diet-induced fatty acid synthesis and leads to the alleviation of triacylglycerol accumulation in the liver.
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Affiliation(s)
- Masaya Shimada
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University.,Division of Life Science for Food, Department of Life Science and Chemistry, Graduate School of Natural Science and Technology, Gifu University
| | - Bungo Shirouchi
- Department of Nutrition Science, Faculty of Nursing and Nutrition, University of Nagasaki
| | - Yota Kobayashi
- Division of Life Science for Food, Department of Life Science and Chemistry, Graduate School of Natural Science and Technology, Gifu University
| | - Mina Higuchi
- Department of Nutrition Science, Faculty of Nursing and Nutrition, University of Nagasaki
| | - Mai Okumura
- Department of Nutrition Science, Faculty of Nursing and Nutrition, University of Nagasaki
| | - Tomoyuki Nakagawa
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University.,Division of Life Science for Food, Department of Life Science and Chemistry, Graduate School of Natural Science and Technology, Gifu University
| | - Takashi Hayakawa
- Department of Applied Life Science, Faculty of Applied Biological Sciences, Gifu University.,Department of Applied Life Studies, College of Nagoya Women's University
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Onuma S, Kinoshita S, Shimba S, Ozono K, Michigami T, Kawai M. The Lack of Bmal1, a Core Clock Gene, in the Intestine Decreases Glucose Absorption in Mice. Endocrinology 2022; 163:6651710. [PMID: 35904419 DOI: 10.1210/endocr/bqac119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Indexed: 11/19/2022]
Abstract
The circadian clock network is an evolutionarily conserved system that regulates systemic metabolism, such as glucose homeostasis. Intestinal tissue is a pivotal organ for the regulation of glucose metabolism, mainly via glucose absorption into the circulation; however, the significance of the intestinal circadian clock network for glucose metabolism remains largely unclear. We herein utilized a mouse model in which Bmal1, a core clock gene, was deleted in an intestine-specific manner (Bmal1Int-/- mice) and demonstrated a rhythmic expression of Sglt1 with its peak at zeitgeber time (ZT) 10.7 ± 2.8 in control mice, whereas this was lost in Bmal1Int-/- mice. Mechanistically, chromatin immunoprecipitation analysis revealed rhythmic binding of CLOCK to the E-box elements in the Sglt1 gene in control mice; however, this was absent in Bmal1Int-/- mice. Accordingly, SGLT1 protein levels were decreased during the dark phase in Bmal1Int-/- mice and this was associated with impaired glucose absorption, leading to a decline in hepatic glycogen levels at ZT4, which was restored by ingestion of high-sucrose water. Additionally, when mice were starved from ZT0, greater expression of the lipolysis-related gene Pnpla2 was observed in adipose tissue of Bmal1Int-/- mice, and this was not noted when glycogen storage was restored by high-sucrose water prior to fasting, suggesting that higher Pnpla2 expression in Bmal1Int-/- mice was likely caused by lower glycogen storage. These results indicate that disruption of the intestinal circadian clock system impairs glucose absorption in the intestine and affects systemic glucose homeostasis.
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Affiliation(s)
- Shinsuke Onuma
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Izumi, Osaka 594-1101, Japan
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan
| | - Saori Kinoshita
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Izumi, Osaka 594-1101, Japan
| | - Shigeki Shimba
- Department of Health Science, School of Pharmacy, Nihon University, Funabashi, Chiba 274-8555, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka 565-0871, Japan
| | - Toshimi Michigami
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Izumi, Osaka 594-1101, Japan
| | - Masanobu Kawai
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Izumi, Osaka 594-1101, Japan
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Begemann K, Oster H. Snack timing affects tissue clock and metabolic responses in male mice. Front Nutr 2022; 9:956641. [PMID: 36034915 PMCID: PMC9410699 DOI: 10.3389/fnut.2022.956641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 07/22/2022] [Indexed: 11/13/2022] Open
Abstract
Snacking of small quantities of palatable food items throughout the day is common in modern societies and is promoted by 24/7 lifestyles. Long-term mistimed high-caloric food intake disrupts endogenous circadian rhythms and supports the development of obesity and other metabolic disorders. However, less is known about the time-of-day dependent effects of snacking. We hypothesized that already a single snacking episode may affect the circadian regulation of metabolic parameters, in particular when the snack is consumed during the daily rest phase. We performed an acute snack experiment in mice by providing access to chow or chocolate either at day- or nighttime and assessed snack effects on core body temperature, locomotor activity, and gene expression in metabolic tissues. Our results show that daytime chocolate snacking leads to a higher body temperature and locomotor activity increase compared to chow and nighttime intake. This goes along with altered clock and metabolic gene expression in peripheral tissues. Changes in nutrient uptake transporter gene expression in the small intestine suggest increased glucose resorption after daytime snacking. Our results indicate an early mechanism for the adipogenic effect of mistimed high-calorie snacking.
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Affiliation(s)
- Kimberly Begemann
- Institute of Neurobiology, University of Lübeck, Lübeck, Germany.,Center of Brain, Behavior, and Metabolism, University of Lübeck, Lübeck, Germany
| | - Henrik Oster
- Institute of Neurobiology, University of Lübeck, Lübeck, Germany.,Center of Brain, Behavior, and Metabolism, University of Lübeck, Lübeck, Germany
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Kinoshita Y, Takahashi H, Katsumata M. Circadian rhythms of the mRNA abundances of clock genes and glucose transporters in the jejunum of weanling-growing pigs. Vet Med Sci 2022; 8:1113-1118. [PMID: 35137560 PMCID: PMC9122404 DOI: 10.1002/vms3.746] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background Whether abundance of glucose transporter mRNAs in the small intestine of pigs shows circadian rhythms and its regulation by clock genes was still unknown. Objectives We examined whether the abundance of glucose transporters and clock genes mRNAs in the small intestine of pigs shows circadian rhythms. Methods Twenty barrows (4 weeks old) were reared under 12 h bright and 12 h dark lighting conditions. During the 3‐week feeding trial, pigs were allowed free access to feed. The abundances of the mRNA of glucose transporters (SGLT1 and GLUT2) and clock genes (Bmal1, Per1, Per2, and Cry2) in the intestine were measured at four time points (ZT2, ZT8, ZT14, and ZT20). Results In the jejunum, the abundance of SGLT1 mRNA was higher at ZT20 and ZT2 and lower at ZT8 and ZT14 (p < 0.05). The abundances of GLUT2 mRNA in the jejunum at ZTs 20 and 2 were tended to be higher than those at ZTs 8 and 14 (p = 0.05). In the jejunum, the abundance of Bmal1 mRNA was higher at ZT8 and ZT14 than at ZT20 and ZT2 (p < 0.05). Further, the abundance of Per1 mRNA at ZT2 was higher than those at the other sampling times (p < 0.05). The abundance of Per1 mRNA at ZT8 was higher than that at ZT14 (p < 0.05), while that of Per2 mRNA was higher at ZT2 than those at ZTs 20 and 14 (p < 0.05). Conclusion We speculate that these circadian rhythms of abundances of glucose transporter mRNAs are regulated by the clock genes expressed in the jejunum.
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Affiliation(s)
- Yuki Kinoshita
- Department of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Hayata Takahashi
- Department of Veterinary Medicine, Azabu University, Sagamihara, Japan
| | - Masaya Katsumata
- Department of Veterinary Medicine, Azabu University, Sagamihara, Japan
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Zou M, Northstone K, Perry R, Johnson L, Leary S. The association between later eating rhythm and adiposity in children and adolescents: a systematic review and meta-analysis. Nutr Rev 2021; 80:1459-1479. [PMID: 34643727 PMCID: PMC9086801 DOI: 10.1093/nutrit/nuab079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
CONTEXT Childhood adiposity, an important predictor of adult chronic disease, has been rising dramatically. Later eating rhythm, termed night eating, is increasing in adults but rarely studied in younger ages. OBJECTIVE The objective of this study was to review the association between later eating rhythm and adiposity in children and adolescents. The aspects of later eating being considered included: energy intake (for evening main meal, evening snack, whole evening period, and around bedtime); timing (any food eaten at later timing); and meal frequency in the evening/night (evening main meal skipping, evening snack consumption). DATA SOURCES Five databases (the Cochrane Library, CINAHL, Embase, MEDLINE (via OVID), and Web of Science) were searched for eligible articles published prior to and including August 2020. DATA EXTRACTION Data extraction and quality assessment were conducted by 2 reviewers independently. DATA ANALYSIS Forty-seven studies were included, all of which were observational. Meta-analysis showed positive associations between both higher energy intake around bedtime (odds ratio [OR] 1.19, 95% CI 1.06, 1.33) and evening main meal skipping (OR 1.30, 95% CI 1.14, 1.48), and adiposity. There was evidence to suggest that consuming evening snacks reduced adiposity, but it was very weak (OR 0.80, 95% CI 0.62, 1.05). No association was seen between eating later and adiposity (OR 1.04, 95% CI 0.68, 1.61). In the narrative analysis, approximately half of the studies suggested that there was no association between later eating rhythm and adiposity, either as a whole or within exposure subsets. CONCLUSION The magnitude of the relationship between later eating rhythm and adiposity is very small, and may vary depending on which aspects of later eating rhythm are under consideration; however, the evidence for this conclusion is of very low certainty. Further research with a more consistent definition of "later timing", and longitudinal studies in different populations, may lead to different conclusions. SYSTEMATIC REVIEW REGISTRATION PROSPERO registration no. CRD42019134187.
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Affiliation(s)
- Mengxuan Zou
- M. Zou, R. Perry and S. Leary are with the NIHR Biomedical Research Centre Nutrition Theme, University of Bristol, Bristol, United Kingdom. K. Northstone is with the Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, United Kingdom. L. Johnson is with the Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, United Kingdom
| | - Kate Northstone
- M. Zou, R. Perry and S. Leary are with the NIHR Biomedical Research Centre Nutrition Theme, University of Bristol, Bristol, United Kingdom. K. Northstone is with the Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, United Kingdom. L. Johnson is with the Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, United Kingdom
| | - Rachel Perry
- M. Zou, R. Perry and S. Leary are with the NIHR Biomedical Research Centre Nutrition Theme, University of Bristol, Bristol, United Kingdom. K. Northstone is with the Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, United Kingdom. L. Johnson is with the Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, United Kingdom
| | - Laura Johnson
- M. Zou, R. Perry and S. Leary are with the NIHR Biomedical Research Centre Nutrition Theme, University of Bristol, Bristol, United Kingdom. K. Northstone is with the Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, United Kingdom. L. Johnson is with the Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, United Kingdom
| | - Sam Leary
- M. Zou, R. Perry and S. Leary are with the NIHR Biomedical Research Centre Nutrition Theme, University of Bristol, Bristol, United Kingdom. K. Northstone is with the Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, United Kingdom. L. Johnson is with the Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, United Kingdom
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Ohlsson B. Theories behind the effect of starch‑ and sucrose‑reduced diets on gastrointestinal symptoms in irritable bowel syndrome (Review). Mol Med Rep 2021; 24:732. [PMID: 34414452 PMCID: PMC8404103 DOI: 10.3892/mmr.2021.12372] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Accepted: 07/22/2021] [Indexed: 12/13/2022] Open
Abstract
Increased amounts of starch and sugar have been added to the diet in the Western world during the last decades. Undigested carbohydrates lead to bacterial fermentation and gas production with diffusion of water, causing abdominal bloating, pain and diarrhea. Therefore, dietary advice is the first line of treatment of irritable bowel syndrome (IBS), a disease characterized by abdominal pain and altered bowel habits without any organic findings. Recently, a diet with a reduction of starch and sucrose led to a marked effect on gastrointestinal (GI) symptoms. The mechanism is unknown, but three possible mechanisms are presented in the present review. First, functional variants of the enzyme sucrase‑isomaltase (SI) have been described in IBS. A subgroup of patients with IBS may thus suffer from partial SI deficiency with reduced digestion of starch and sucrose. Second, fructose absorption is less efficient than glucose absorption, which may lead to a physiological fructose malabsorption when ingesting high amounts of sucrose. A third mechanism is that high‑sugar diets causing hyperglycemia, hyperinsulinemia and weight gain have led to painful neuropathy in animal models; whereas, improved metabolic control in humans has led to improvement of neuropathy. Starch‑ and sucrose‑reduced diets lead to decreased levels of C‑peptide, insulin, gastric inhibitory peptide, leptin and weight reduction. These metabolic changes may reduce the excitability of the hypersensitive nervous system often found in IBS and, thereby, lead to the reduced symptoms found after the diet. In conclusion, further studies are needed to investigate the pathophysiology behind development of symptoms after starch and sucrose intake, and the mechanisms behind symptom relief after reduced intake.
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Affiliation(s)
- Bodil Ohlsson
- Department of Internal Medicine, Lund University, Skåne University Hospital, 20502 Malmö, Sweden
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12
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Koop S, Oster H. Eat, sleep, repeat - endocrine regulation of behavioural circadian rhythms. FEBS J 2021; 289:6543-6558. [PMID: 34228879 DOI: 10.1111/febs.16109] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/23/2021] [Accepted: 07/05/2021] [Indexed: 02/07/2023]
Abstract
The adaptation of organisms to a rhythmic environment is mediated by an internal timing system termed the circadian clock. In mammals, molecular clocks are found in all tissues and organs. This circadian clock network regulates the release of many hormones, which in turn influence some of the most vital behavioural functions. Sleep-wake cycles are under strict circadian control with strong influence of rhythmic hormones such as melatonin, cortisol and others. Food intake, in contrast, receives circadian modulation through hormones such as leptin, ghrelin, insulin and orexin. A third behavioural output covered in this review is mating and bonding behaviours, regulated through circadian rhythms in steroid hormones and oxytocin. Together, these data emphasize the pervasive influence of the circadian clock system on behavioural outputs and its mediation through endocrine networks.
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Affiliation(s)
- Sarah Koop
- Centre of Brain, Behavior and Metabolism, Institute of Neurobiology, University of Lübeck, Germany
| | - Henrik Oster
- Centre of Brain, Behavior and Metabolism, Institute of Neurobiology, University of Lübeck, Germany
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13
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Gutierrez Lopez DE, Lashinger LM, Weinstock GM, Bray MS. Circadian rhythms and the gut microbiome synchronize the host's metabolic response to diet. Cell Metab 2021; 33:873-887. [PMID: 33789092 DOI: 10.1016/j.cmet.2021.03.015] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 01/22/2021] [Accepted: 03/15/2021] [Indexed: 12/14/2022]
Abstract
The molecular circadian clock and symbiotic host-microbe relationships both evolved as mechanisms that enhance metabolic responses to environmental challenges. The gut microbiome benefits the host by breaking down diet-derived nutrients indigestible by the host and generating microbiota-derived metabolites that support host metabolism. Similarly, cellular circadian clocks optimize organismal physiology to the environment by influencing the timing and coordination of metabolic processes. Host-microbe interactions are influenced by dietary quality and timing, as well as daily light/dark cycles that entrain circadian rhythms in the host. Together, the gut microbiome and the molecular circadian clock play a coordinated role in neural processing, metabolism, adipogenesis, inflammation, and disease initiation and progression. This review examines the bidirectional interactions between the circadian clock, gut microbiota, and host metabolic systems and their effects on obesity and energy homeostasis. Directions for future research and the development of therapies that leverage these systems to address metabolic disease are highlighted.
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Affiliation(s)
- Diana E Gutierrez Lopez
- Department of Nutritional Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Laura M Lashinger
- Department of Nutritional Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - George M Weinstock
- The Jackson Laboratory for Genomic Medicine, Farmington, CT 06032, USA; Department of Genetics and Genome Sciences, University of Connecticut School of Medicine, Storrs, CT 06032, USA
| | - Molly S Bray
- Department of Nutritional Sciences, The University of Texas at Austin, Austin, TX 78712, USA.
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14
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Barrea L, Frias-Toral E, Aprano S, Castellucci B, Pugliese G, Rodriguez-Veintimilla D, Vitale G, Gentilini D, Colao A, Savastano S, Muscogiuri G. The clock diet: a practical nutritional guide to manage obesity through chrononutrition. Minerva Med 2021; 113:172-188. [PMID: 33913659 DOI: 10.23736/s0026-4806.21.07207-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chronobiology studies the biological rhythms or circadian cycles of living organisms and their adaptation to external changes. Biological rhythms can affect hormone production cycles such as sleep/wake, and nutrition/fasting, but these factors can also alter the circadian rhythm (CR). In recent years, numerous studies have highlighted how feeding times and frequency can influence biological rhythms. Additionally, individuals' chronotype, working shifts, and food intake can make a deep impact on people's tendency to develop obesity and metabolic diseases. In this context, a single food and a specific combination of these, can also affect the CR and fasting cycle and consequently body weight and viceversa. The purpose of the review is to propose practical nutritional recommendations to help in resynchronizing the circadian rhythm as a tool in weight control.
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Affiliation(s)
- Luigi Barrea
- Dipartimento di Scienze Umanistiche, Università Telematica Pegaso, Naples, Italy - .,Endocrinology Unit, Department of Clinical Medicine and Surgery, Centro Italiano per la cura e il Benessere del paziente con Obesità (C.I.B.O), University Medical School of Naples, Naples, Italy -
| | - Evelyn Frias-Toral
- Research Committee, SOLCA Guayaquil, Guayaquil, Ecuador.,Palliative Care Residency, Universidad Católica Santiago de Guayaquil, Guayaquil, Ecuador
| | - Sara Aprano
- Endocrinology Unit, Department of Clinical Medicine and Surgery, Centro Italiano per la cura e il Benessere del paziente con Obesità (C.I.B.O), University Medical School of Naples, Naples, Italy.,Unit of Endocrinology, Dipartimento di Medicina Clinica e Chirurgia, Federico II University Medical School of Naples, Naples, Italy
| | - Bianca Castellucci
- Endocrinology Unit, Department of Clinical Medicine and Surgery, Centro Italiano per la cura e il Benessere del paziente con Obesità (C.I.B.O), University Medical School of Naples, Naples, Italy.,Unit of Endocrinology, Dipartimento di Medicina Clinica e Chirurgia, Federico II University Medical School of Naples, Naples, Italy
| | - Gabriella Pugliese
- Endocrinology Unit, Department of Clinical Medicine and Surgery, Centro Italiano per la cura e il Benessere del paziente con Obesità (C.I.B.O), University Medical School of Naples, Naples, Italy.,Unit of Endocrinology, Dipartimento di Medicina Clinica e Chirurgia, Federico II University Medical School of Naples, Naples, Italy
| | | | - Giovanni Vitale
- Laboratory of Geriatric and Oncologic Neuroendocrinology Research, Istituto Auxologico Italiano IRCCS, Cusano Milanino, Milan, Italy.,Department of Medical Biotechnologies and Translational Medicine, University of Milan, Milan, Italy
| | - Davide Gentilini
- Department of Brain and Behavioral Sciences, University of Pavia, Pavia, Italy.,Bioinformatics and Statistical Genomics Unit, Istituto Auxologico Italiano IRCCS, Cusano Milanino, Milan, Italy
| | - Annamaria Colao
- Endocrinology Unit, Department of Clinical Medicine and Surgery, Centro Italiano per la cura e il Benessere del paziente con Obesità (C.I.B.O), University Medical School of Naples, Naples, Italy.,Unit of Endocrinology, Dipartimento di Medicina Clinica e Chirurgia, Federico II University Medical School of Naples, Naples, Italy.,Cattedra Unesco Educazione alla salute e allo sviluppo sostenibile, University Federico II, Naples, Italy
| | - Silvia Savastano
- Endocrinology Unit, Department of Clinical Medicine and Surgery, Centro Italiano per la cura e il Benessere del paziente con Obesità (C.I.B.O), University Medical School of Naples, Naples, Italy.,Unit of Endocrinology, Dipartimento di Medicina Clinica e Chirurgia, Federico II University Medical School of Naples, Naples, Italy
| | - Giovanna Muscogiuri
- Endocrinology Unit, Department of Clinical Medicine and Surgery, Centro Italiano per la cura e il Benessere del paziente con Obesità (C.I.B.O), University Medical School of Naples, Naples, Italy.,Unit of Endocrinology, Dipartimento di Medicina Clinica e Chirurgia, Federico II University Medical School of Naples, Naples, Italy.,Cattedra Unesco Educazione alla salute e allo sviluppo sostenibile, University Federico II, Naples, Italy
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15
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Abstract
Many molecular, physiological and behavioural processes display distinct 24-hour rhythms that are directed by the circadian system. The master clock, located in the suprachiasmatic nucleus region of the hypothalamus, is synchronized or entrained by the light-dark cycle and, in turn, synchronizes clocks present in peripheral tissues and organs. Other environmental cues, most importantly feeding time, also synchronize peripheral clocks. In this way, the circadian system can prepare the body for predictable environmental changes such as the availability of nutrients during the normal feeding period. This Review summarizes existing knowledge about the diurnal regulation of gastrointestinal processes by circadian clocks present in the digestive tract and its accessory organs. The circadian control of gastrointestinal digestion, motility, hormones and barrier function as well as of the gut microbiota are discussed. An overview is given of the interplay between different circadian clocks in the digestive system that regulate glucose homeostasis and lipid and bile acid metabolism. Additionally, the bidirectional interaction between the master clock and peripheral clocks in the digestive system, encompassing different entraining factors, is described. Finally, the possible behavioural adjustments or pharmacological strategies for the prevention and treatment of the adverse effects of chronodisruption are outlined.
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16
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Abstract
The endogenous timekeeping system evolved to anticipate the time of the day through the 24 hours cycle of the Earth's rotation. In mammals, the circadian clock governs rhythmic physiological and behavioral processes, including the daily oscillation in glucose metabolism, food intake, energy expenditure, and whole-body insulin sensitivity. The results from a series of studies have demonstrated that environmental or genetic alterations of the circadian cycle in humans and rodents are strongly associated with metabolic diseases such as obesity and type 2 diabetes. Emerging evidence suggests that astrocyte clocks have a crucial role in regulating molecular, physiological, and behavioral circadian rhythms such as glucose metabolism and insulin sensitivity. Given the concurrent high prevalence of type 2 diabetes and circadian disruption, understanding the mechanisms underlying glucose homeostasis regulation by the circadian clock and its dysregulation may improve glycemic control. In this review, we summarize the current knowledge on the tight interconnection between the timekeeping system, glucose homeostasis, and insulin sensitivity. We focus specifically on the involvement of astrocyte clocks, at the organism, cellular, and molecular levels, in the regulation of glucose metabolism.
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Affiliation(s)
- Olga Barca-Mayo
- Circadian and Glial Biology Lab, Physiology Department, Molecular Medicine and Chronic Diseases Research Centre (CiMUS), University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Miguel López
- NeurObesity Lab, Physiology Department, Molecular Medicine and Chronic Diseases Research Centre (CiMUS), University of Santiago de Compostela, Santiago de Compostela, Spain
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17
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Koepsell H. Glucose transporters in the small intestine in health and disease. Pflugers Arch 2020; 472:1207-1248. [PMID: 32829466 PMCID: PMC7462918 DOI: 10.1007/s00424-020-02439-5] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 07/11/2020] [Accepted: 07/17/2020] [Indexed: 12/23/2022]
Abstract
Absorption of monosaccharides is mainly mediated by Na+-D-glucose cotransporter SGLT1 and the facititative transporters GLUT2 and GLUT5. SGLT1 and GLUT2 are relevant for absorption of D-glucose and D-galactose while GLUT5 is relevant for D-fructose absorption. SGLT1 and GLUT5 are constantly localized in the brush border membrane (BBM) of enterocytes, whereas GLUT2 is localized in the basolateral membrane (BLM) or the BBM plus BLM at low and high luminal D-glucose concentrations, respectively. At high luminal D-glucose, the abundance SGLT1 in the BBM is increased. Hence, D-glucose absorption at low luminal glucose is mediated via SGLT1 in the BBM and GLUT2 in the BLM whereas high-capacity D-glucose absorption at high luminal glucose is mediated by SGLT1 plus GLUT2 in the BBM and GLUT2 in the BLM. The review describes functions and regulations of SGLT1, GLUT2, and GLUT5 in the small intestine including diurnal variations and carbohydrate-dependent regulations. Also, the roles of SGLT1 and GLUT2 for secretion of enterohormones are discussed. Furthermore, diseases are described that are caused by malfunctions of small intestinal monosaccharide transporters, such as glucose-galactose malabsorption, Fanconi syndrome, and fructose intolerance. Moreover, it is reported how diabetes, small intestinal inflammation, parental nutrition, bariatric surgery, and metformin treatment affect expression of monosaccharide transporters in the small intestine. Finally, food components that decrease D-glucose absorption and drugs in development that inhibit or downregulate SGLT1 in the small intestine are compiled. Models for regulations and combined functions of glucose transporters, and for interplay between D-fructose transport and metabolism, are discussed.
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Affiliation(s)
- Hermann Koepsell
- Institute for Anatomy and Cell Biology, University of Würzburg, Koellikerstr 6, 97070, Würzburg, Germany.
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18
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Zou M, Northstone K, Perry R, Johnson L, Leary S. The impact of later eating rhythm on childhood adiposity: protocol for a systematic review. Syst Rev 2019; 8:290. [PMID: 31771660 PMCID: PMC6878614 DOI: 10.1186/s13643-019-1226-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2019] [Accepted: 11/08/2019] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Childhood adiposity has increased dramatically in the last few decades and is an important predictor of adulthood chronic disease. Later eating rhythm, termed night eating (NE), is increasingly prevalent in adults; however, the prevalence of NE in children and relationship between NE and adiposity in children still remains uncertain. The aim of this work is to review the association between adiposity in children and adolescents and NE, in terms of calorie intake, timing and meal frequency in the evening/night. METHODS The Cochrane library, CINAHL, Embase, MEDLINE (via OVID) and Web of Science databases will be searched from inception to November 2019 for randomised controlled trials (RCTs) and observational studies (cohort, cross-sectional and case-control studies) which investigate the association between later vs. earlier timing of food intake at night or relatively more vs. less energy intake in any eating occasions or time period after 4 pm on adiposity in children and adolescents (4-18 years). The outcomes will be body mass index (BMI)/BMI standard deviation score (BMI-SDS or BMI Z-score), waist circumference (WC), fat mass index (FMI)/percentage of body fat (%BF) or waist to hip ratio (WHR). No language restriction will be applied. Screening for eligibility from the title and abstracts and data extraction from the full texts will be carried out by two reviewers independently. References listed in the included studies will be hand-searched for any additional articles. The quality of included RCT studies will be assessed using Revised Cochrane Risk of Bias tool (RoB 2), and of observational studies using Newcastle Ottawa scale. A qualitative synthesis of the results will be presented, and meta-analysis will be conducted, where appropriate. DISCUSSION The planned systematic review will investigate the association between later eating rhythm and adiposity in children and adolescents. Understanding the best meal size, timing of energy intake and meal frequency across the evening time for maintaining healthy weight in children is important in order to give parents the best advice to help prevent adulthood obesity and associated chronic diseases in their children. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42019134187.
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Affiliation(s)
- Mengxuan Zou
- Bristol Dental School, Faculty of Health Sciences, University of Bristol, Bristol, BS2 8AE, UK.
| | - Kate Northstone
- Bristol Medical School, Faculty of Health Sciences, University of Bristol, Bristol, BS8 2BN, UK
| | - Rachel Perry
- NIHR Biomedical Research Centre in Nutrition, University of Bristol, Bristol, BS2 8AE, UK
| | - Laura Johnson
- Centre for Exercise, Nutrition and Health Sciences, School of Policy Studies, University of Bristol, Bristol, BS8 1TZ, UK
| | - Sam Leary
- NIHR Biomedical Research Centre in Nutrition, University of Bristol, Bristol, BS2 8AE, UK
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19
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Daily expression of sodium-dependent glucose cotransporter-1 protein in jejunum during rat ontogeny. ACTA ACUST UNITED AC 2019; 5:290-296. [PMID: 31528732 PMCID: PMC6737494 DOI: 10.1016/j.aninu.2019.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Revised: 01/17/2019] [Accepted: 04/02/2019] [Indexed: 11/21/2022]
Abstract
It is widely known that intestinal capacities such as the enzymatic hydrolysis of carbohydrates, lipids and proteins, and the subsequent absorption of the hydrolyzed products, are evolutionary matched to dietary loads and feeding behaviors. In this study, we demonstrate that the protein expression of apically located sodium-dependent glucose cotransporter-1 (SGLT-1) throughout rat ontogeny is daily adjusted to afford glucose uptake when the load of this metabolically essential monosaccharide in the intestinal lumen is maximum. The jejunal expression of SGLT-1 protein in 14 one-day-old suckling pups was found to increase at dark and early light phase (P < 0.05), when they have a better access to mother milk. In weaning 21-d-old and juvenile 28-d-old rats, the cotransporter expression was high throughout the entire day (P < 0.05). Finally, adult 90-d-old rats showed a well-developed circadian rhythm for SGLT-1 protein (P < 0.05), whose expression increased at late light and dark phase when the highest intestinal glucose load was achieved. To our knowledge, these results are the first reporting the daily profile of SGLT-1 expression during rat early developmental stage and may contribute to understand the biological significance of a well-established molecular capacity to deal with the crucial increase of glucose load in the diet during the weaning process.
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20
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Sussman W, Stevenson M, Mowdawalla C, Mota S, Ragolia L, Pan X. BMAL1 controls glucose uptake through paired-homeodomain transcription factor 4 in differentiated Caco-2 cells. Am J Physiol Cell Physiol 2019; 317:C492-C501. [PMID: 31216190 PMCID: PMC6766619 DOI: 10.1152/ajpcell.00058.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 02/08/2023]
Abstract
The transcription factor aryl hydrocarbon receptor nuclear translocator-like protein-1 (BMAL1) is an essential regulator of the circadian clock, which controls the 24-h cycle of physiological processes such as nutrient absorption. To examine the role of BMAL1 in small intestinal glucose absorption, we used differentiated human colon adenocarcinoma cells (Caco-2 cells). Here, we show that BMAL1 regulates glucose uptake in differentiated Caco-2 cells and that this process is dependent on the glucose transporter sodium-glucose cotransporter 1 (SGLT1). Mechanistic studies show that BMAL1 regulates glucose uptake by controlling the transcription of SGLT1 involving paired-homeodomain transcription factor 4 (PAX4), a transcriptional repressor. This is supported by the observation that clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated endonuclease Cas9 (Cas9) knockdown of PAX4 increases SGLT1 and glucose uptake. Chromatin immunoprecipitation (ChIP) and ChIP-quantitative PCR assays show that the knockdown or overexpression of BMAL1 decreases or increases the binding of PAX4 to the hepatocyte nuclear factor 1-α binding site of the SGLT1 promoter, respectively. These findings identify BMAL1 as a critical mediator of small intestine carbohydrate absorption and SGLT1.
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Affiliation(s)
- Whitney Sussman
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York
- Diabetes and Obesity Research Center, New York University Winthrop Hospital, Mineola, New York
| | - Matthew Stevenson
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York
- Diabetes and Obesity Research Center, New York University Winthrop Hospital, Mineola, New York
| | - Cyrus Mowdawalla
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York
- Diabetes and Obesity Research Center, New York University Winthrop Hospital, Mineola, New York
| | - Samantha Mota
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York
- Diabetes and Obesity Research Center, New York University Winthrop Hospital, Mineola, New York
| | - Louis Ragolia
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York
- Diabetes and Obesity Research Center, New York University Winthrop Hospital, Mineola, New York
| | - Xiaoyue Pan
- Department of Foundations of Medicine, New York University Long Island School of Medicine, Mineola, New York
- Diabetes and Obesity Research Center, New York University Winthrop Hospital, Mineola, New York
- Department of Cell Biology, State University of New York Downstate Medical Center, Brooklyn, New York
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21
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Sun S, Hanzawa F, Umeki M, Matsuyama Y, Nishimura N, Ikeda S, Mochizuki S, Oda H. Impacts of high-sucrose diet on circadian rhythms in the small intestine of rats. Chronobiol Int 2019; 36:826-837. [DOI: 10.1080/07420528.2019.1592185] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Shumin Sun
- Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, Japan
| | - Fumiaki Hanzawa
- Department of Nutritional Science, Nagoya University of Arts and Sciences, Nisshin, Japan
| | - Miki Umeki
- Faculty of Education and Welfare Science, Oita University, Oita, Japan
| | - Yasuko Matsuyama
- Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, Japan
| | - Naomichi Nishimura
- Academic Institute, College of Agriculture, Shizuoka University, Shizuoka, Japan
| | - Saiko Ikeda
- Department of Nutritional Science, Nagoya University of Arts and Sciences, Nisshin, Japan
| | - Satoshi Mochizuki
- Faculty of Education and Welfare Science, Oita University, Oita, Japan
| | - Hiroaki Oda
- Laboratory of Nutritional Biochemistry, Nagoya University, Nagoya, Japan
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22
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Abstract
Insulin resistance is a main determinant in the development of type 2 diabetes mellitus and a major cause of morbidity and mortality. The circadian timing system consists of a central brain clock in the hypothalamic suprachiasmatic nucleus and various peripheral tissue clocks. The circadian timing system is responsible for the coordination of many daily processes, including the daily rhythm in human glucose metabolism. The central clock regulates food intake, energy expenditure and whole-body insulin sensitivity, and these actions are further fine-tuned by local peripheral clocks. For instance, the peripheral clock in the gut regulates glucose absorption, peripheral clocks in muscle, adipose tissue and liver regulate local insulin sensitivity, and the peripheral clock in the pancreas regulates insulin secretion. Misalignment between different components of the circadian timing system and daily rhythms of sleep-wake behaviour or food intake as a result of genetic, environmental or behavioural factors might be an important contributor to the development of insulin resistance. Specifically, clock gene mutations, exposure to artificial light-dark cycles, disturbed sleep, shift work and social jet lag are factors that might contribute to circadian disruption. Here, we review the physiological links between circadian clocks, glucose metabolism and insulin sensitivity, and present current evidence for a relationship between circadian disruption and insulin resistance. We conclude by proposing several strategies that aim to use chronobiological knowledge to improve human metabolic health.
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Affiliation(s)
- Dirk Jan Stenvers
- Department of Endocrinology and Metabolism, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
| | - Frank A J L Scheer
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
- Medical Chronobiology Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Boston, MA, USA
| | - Patrick Schrauwen
- Department of Nutrition and Movement Sciences, NUTRIM, School for Nutrition and Translational Research in Metabolism, Maastricht University Medical Center, Maastricht, Netherlands
| | - Susanne E la Fleur
- Department of Endocrinology and Metabolism, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
- Laboratory for Endocrinology, Department of Clinical Chemistry, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands
- Netherlands Institute for Neuroscience (NIN), Royal Dutch Academy of Arts and Sciences (KNAW), Amsterdam, Netherlands
| | - Andries Kalsbeek
- Department of Endocrinology and Metabolism, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.
- Laboratory for Endocrinology, Department of Clinical Chemistry, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands.
- Netherlands Institute for Neuroscience (NIN), Royal Dutch Academy of Arts and Sciences (KNAW), Amsterdam, Netherlands.
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23
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Hernández-García J, Navas-Carrillo D, Orenes-Piñero E. Alterations of circadian rhythms and their impact on obesity, metabolic syndrome and cardiovascular diseases. Crit Rev Food Sci Nutr 2019; 60:1038-1047. [PMID: 30633544 DOI: 10.1080/10408398.2018.1556579] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Circadian system is comprised by central circadian pacemaker and several peripheral clocks that receive information from the external environment, synchronizing the circadian clocks. It is widely known that physiology is rhythmic and that the rupture of this rhythmicity can generate serious consequences. Circadian clocks, led by suprachiasmatic nucleus (SCN) in the central nervous system, are the responsible for generating this biological rhythmicity. These clocks are affected by external signals such as light (changes between day and night) and feeding rhythms. In this review, the basic principles of the circadian system and current knowledge of biological clocks are addressed, analyzing the relationship between circadian system, food intake, nutrition, and associated metabolic processes. In addition, the consequences occurring when these systems are not well coordinated with each other, such as the development of cardiovascular and metabolic pathologies, will be thoroughly discussed.
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Affiliation(s)
| | - Diana Navas-Carrillo
- Department of Surgery, Hospital de la Vega Lorenzo Guirao, University of Murcia, Murcia, Spain
| | - Esteban Orenes-Piñero
- Department of Biochemistry and Molecular Biology-A, University of Murcia, Murcia, Spain
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24
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Yamauchi H, Honma K, Mochizuki K, Goda T. Regulation of the circadian rhythmic expression of Sglt1 in the mouse small intestine through histone acetylation and the mRNA elongation factor, BRD4-P-TEFb. Biosci Biotechnol Biochem 2018; 82:1176-1179. [PMID: 29557282 DOI: 10.1080/09168451.2018.1451743] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Jejunal sodium/glucose co-transporter (Sglt1) displays circadian expression. The jejunum was collected every 4 h from mice, and we examined histone acetylation and binding of bromodomain-containing protein-4 (BRD4) around of the gene. Histone acetylation increased in the transcribed region of Sglt1 prior to induction of the gene. Furthermore, the binding of mRNA elongation factor around the gene showed circadian rhythm.
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Affiliation(s)
- Hiroyuki Yamauchi
- a Laboratory of Nutritional Physiology, Department of Nutrition, Graduate School of Nutritional and Environmental Sciences , University of Shizuoka , Shizuoka , Japan
| | - Kazue Honma
- a Laboratory of Nutritional Physiology, Department of Nutrition, Graduate School of Nutritional and Environmental Sciences , University of Shizuoka , Shizuoka , Japan
| | - Kazuki Mochizuki
- b Laboratory of Food and Nutritional Sciences, Faculty of Life and Environmental Sciences, Department of Local Produce and Food Sciences , University of Yamanashi , Yamanashi , Japan
| | - Toshinao Goda
- a Laboratory of Nutritional Physiology, Department of Nutrition, Graduate School of Nutritional and Environmental Sciences , University of Shizuoka , Shizuoka , Japan
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25
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Chrono-nutrition: a review of current evidence from observational studies on global trends in time-of-day of energy intake and its association with obesity. Proc Nutr Soc 2016; 75:487-500. [DOI: 10.1017/s0029665116000306] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The importance of the circadian rhythm in regulating human food intake behaviour and metabolism has long been recognised. However, little is known as to how energy intake is distributed over the day in existing populations, and its potential association with obesity. The present review describes global trends in time-of-day of energy intake in the general population based on data from cross-sectional surveys and longitudinal cohorts. Evidence of the association between time-of-day of energy intake and obesity is also summarised. Overall, there were a limited number of cross-sectional surveys and longitudinal cohorts that provided data on time-of-day of energy intake. In the identified studies, a wide variation in time-of-day of energy intake was observed, with patterns of energy distribution varying greatly by country and geographical area. In relation to obesity, eight cross-sectional surveys and two longitudinal cohorts were identified. The association between time-of-day of energy intake and obesity varied widely, with several studies reporting a positive link between evening energy intake and obesity. In conclusion, the current review summarises global trends in time-of-day of energy intake. The large variations across countries and global regions could have important implications to health, emphasising the need to understand the socio-environmental factors guiding such differences in eating patterns. Evidence of the association between time-of-day of energy intake and BMI also varied. Further larger scale collaborations between various countries and regions are needed to sum data from existing surveys and cohorts, and guide our understanding of the role of chrono-nutrition in health.
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26
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Abstract
Robust circadian rhythms in metabolic processes have been described in both humans and animal models, at the whole body, individual organ, and even cellular level. Classically, these time-of-day-dependent rhythms have been considered secondary to fluctuations in energy/nutrient supply/demand associated with feeding/fasting and wake/sleep cycles. Renewed interest in this field has been fueled by studies revealing that these rhythms are driven, at least in part, by intrinsic mechanisms and that disruption of metabolic synchrony invariably increases the risk of cardiometabolic disease. The objectives of this paper are to provide a comprehensive review regarding rhythms in glucose, lipid, and protein/amino acid metabolism, the relative influence of extrinsic (eg, neurohumoral factors) versus intrinsic (eg, cell autonomous circadian clocks) mediators, the physiologic roles of these rhythms in terms of daily fluctuations in nutrient availability and activity status, as well as the pathologic consequences of dyssynchrony.
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Affiliation(s)
- Graham R McGinnis
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Martin E Young
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
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27
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Abstract
Various intestinal functions exhibit circadian rhythmicity. Disruptions in these rhythms as in shift workers and transcontinental travelers are associated with intestinal discomfort. Circadian rhythms are controlled at the molecular level by core clock and clock-controlled genes. These clock genes are expressed in intestinal cells, suggesting that they might participate in the circadian regulation of intestinal functions. A major function of the intestine is nutrient absorption. Here, we will review absorption of proteins, carbohydrates, and lipids and circadian regulation of various transporters involved in their absorption. A better understanding of circadian regulation of intestinal absorption might help control several metabolic disorders and attenuate intestinal discomfort associated with disruptions in sleep-wake cycles.
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Affiliation(s)
- M Mahmood Hussain
- Department of Cell Biology and Pediatrics, SUNY Downstate Medical Center, Brooklyn, New York, USA, and VA New York Harbor Healthcare System, Brooklyn, New York, USA
| | - Xiaoyue Pan
- Department of Cell Biology and Pediatrics, SUNY Downstate Medical Center, Brooklyn, New York, USA, and VA New York Harbor Healthcare System, Brooklyn, New York, USA
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ZHU LITING, YU JUN, ZHANG WENYI, XIE BIN, ZHU YI. Research progress on the central mechanism underlying regulation of visceral biological rhythm by per2 (Review). Mol Med Rep 2014; 10:2241-8. [DOI: 10.3892/mmr.2014.2559] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2013] [Accepted: 04/25/2014] [Indexed: 11/05/2022] Open
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Tahara Y, Shibata S. Chrono-biology, chrono-pharmacology, and chrono-nutrition. J Pharmacol Sci 2014; 124:320-35. [PMID: 24572815 DOI: 10.1254/jphs.13r06cr] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The circadian clock system in mammals drives many physiological processes including the daily rhythms of sleep-wake behavior, hormonal secretion, and metabolism. This system responds to daily environmental changes, such as the light-dark cycle, food intake, and drug administration. In this review, we focus on the central and peripheral circadian clock systems in response to drugs, food, and nutrition. We also discuss the adaptation and anticipation mechanisms of our body with regard to clock system regulation of various kinetic and dynamic pathways, including absorption, distribution, metabolism, and excretion of drugs and nutrients. "Chrono-pharmacology" and "chrono-nutrition" are likely to become important research fields in chrono-biological studies.
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Affiliation(s)
- Yu Tahara
- Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Japan
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Tahara Y, Shibata S. Chronobiology and nutrition. Neuroscience 2013; 253:78-88. [PMID: 24007937 DOI: 10.1016/j.neuroscience.2013.08.049] [Citation(s) in RCA: 124] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2013] [Revised: 08/21/2013] [Accepted: 08/24/2013] [Indexed: 12/15/2022]
Abstract
Numerous long-term studies have investigated the circadian clock system in mammals, which organizes physiological functions, including metabolism, digestion, and absorption of food, and energy expenditure. Food or nutrition can be a synchronizer for the circadian clock systems, as potent as the external light-dark signal can be. Recent studies have investigated different kinds of food, frequency of consumption, and time of consumption for optimizing body clock and ensuring healthy habits. In this review, we discuss recent studies investigating chronobiology and nutrition, and then summarize available information as "Chrono-nutrition" for the development of a new standardized research strategy.
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Affiliation(s)
- Y Tahara
- Laboratory of Physiology and Pharmacology, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
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Pácha J, Sumová A. Circadian regulation of epithelial functions in the intestine. Acta Physiol (Oxf) 2013; 208:11-24. [PMID: 23461998 DOI: 10.1111/apha.12090] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Revised: 02/21/2013] [Accepted: 02/21/2013] [Indexed: 12/24/2022]
Abstract
Many physiological functions exhibit a diurnal rhythmicity that is influenced by biological clocks and feeding rhythms. In this review, we discuss the growing evidence showing the important role of circadian rhythms in regulating intestinal mucosa. First, we introduce the molecular timing system and the interrelationship between the master biological clock in the suprachiasmatic nuclei of the brain and the peripheral intestinal clock and provide evidence that the intestinal clock is entrained with the external environment. Second, we review the circadian rhythmicity of enterocyte proliferation and the largely unknown regulatory mechanisms behind these rhythms. Finally, we focus on the circadian clock control of food processing that functions by regulating the expression of digestive enzymes and intestinal nutrient and salt transporters. The concepts to be discussed highlight the ability of the intestinal epithelium to utilize self-sustained clock signals together with signals associated with changes in the cellular environment and to use endogenous temporal control of the gastrointestinal functions to meet varying physiological and pathophysiological demands. The fact that internal de-synchronizations within the body, such as those that occur in shift workers or with changes in food intake behaviour, are often associated with malfunctions of the gastrointestinal tract indicates that more information about the connections between the circadian clock and intestinal mucosa/transporting enterocytes could provide clues for future therapies.
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Affiliation(s)
- J. Pácha
- Institute of Physiology; Academy of Sciences of the Czech Republic; Prague; Czech Republic
| | - A. Sumová
- Institute of Physiology; Academy of Sciences of the Czech Republic; Prague; Czech Republic
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PER1 modulates SGLT1 transcription in vitro independent of E-box status. Dig Dis Sci 2012; 57:1525-36. [PMID: 22526585 PMCID: PMC3376756 DOI: 10.1007/s10620-012-2166-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Accepted: 04/03/2012] [Indexed: 12/09/2022]
Abstract
BACKGROUND AND AIMS The intestine demonstrates profound circadian rhythmicity in glucose absorption in rodents, mediated entirely by rhythmicity in the transcription, translation, and function of the sodium glucose co-transporter SGLT1 (Slc5a1). Clock genes are rhythmic in the intestine and have been implicated in the regulation of rhythmicity of other intestinal genes; however, their role in the regulation of SGLT1 is unknown. We investigated the effects of one clock gene, PER1, on SGLT1 transcription in vitro. METHODS Caco-2 cells were stably transfected with knockdown vectors for PER1 and mRNA expression of clock genes and SGLT1 determined using quantitative polymerase chain reaction (qPCR). Chinese hamster ovary (CHO) cells were transiently cotransfected with combinations of the PER1 expression vectors and the wild-type SGLT1-luciferase promoter construct or the promoter with mutated E-box sequences. RESULTS Knockdown of PER1 increased native SGLT1 expression in Caco-2 enterocytes, while promoter studies confirmed that the inhibitory activity of PER1 on SGLT1 occurs via the proximal 1 kb of the SGLT1 promoter. E-box sites exerted a suppressive effect on the SGLT1 promoter; however, mutation of E-boxes had little effect on the inhibitory activity of PER1 on the SGLT1 promoter suggesting that the actions of PER1 on SGLT1 are independent of E-boxes. CONCLUSIONS Our findings suggest that PER1 exerts an indirect suppressive effect on SGLT1, possibly acting via other clock-controlled genes binding to non-E-box sites on the SGLT1 promoter. Understanding the regulation of rhythmicity of SGLT1 may lead to new treatments for the modulation of SGLT1 expression in conditions such as malabsorption, diabetes, and obesity.
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Balakrishnan A, Tavakkolizadeh A, Rhoads DB. Circadian clock genes and implications for intestinal nutrient uptake. J Nutr Biochem 2012; 23:417-22. [PMID: 22417783 DOI: 10.1016/j.jnutbio.2012.01.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 11/30/2011] [Accepted: 01/26/2012] [Indexed: 01/29/2023]
Abstract
There has recently been increasing interest in the phenomenon of circadian rhythmicity. We have used circadian rhythms as a means to understanding the regulation of glucose absorption in the intestine. We and others have previously demonstrated rhythmicity in intestinal glucose uptake, mediated by rhythmicity in the expression of the sodium glucose cotransporter 1. Rhythmicity of clock gene expression was subsequently confirmed in the intestine, a phenomenon also demonstrated in other viscera. Clock genes have since been shown via a combination of in vitro and in vivo techniques to play a role in the transcriptional regulation of key absorptive proteins.
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Affiliation(s)
- Anita Balakrishnan
- Department of Surgery, Brigham and Women's Hospital, and Department of Surgery, Harvard Medical School, Boston, Massachusetts 02115, USA.
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Soták M, Polidarová L, Musílková J, Hock M, Sumová A, Pácha J. Circadian regulation of electrolyte absorption in the rat colon. Am J Physiol Gastrointest Liver Physiol 2011; 301:G1066-74. [PMID: 21903759 DOI: 10.1152/ajpgi.00256.2011] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The intestinal transport of nutrients exhibits distinct diurnal rhythmicity, and the enterocytes harbor a circadian clock. However, temporal regulation of the genes involved in colonic ion transport, i.e., ion transporters and channels operating in absorption and secretion, remains poorly understood. To address this issue, we assessed the 24-h profiles of expression of genes encoding the sodium pump (subunits Atp1a1 and Atp1b1), channels (α-, β-, and γ-subunits of Enac and Cftr), transporters (Dra, Ae1, Nkcc1, Kcc1, and Nhe3), and the Na(+)/H(+) exchanger (NHE) regulatory factor (Nherf1) in rat colonic mucosa. Furthermore, we investigated temporal changes in the spatial localization of the clock genes Per1, Per2, and Bmal1 and the genes encoding ion transporters and channels along the crypt axis. In rats fed ad libitum, the expression of Atp1a1, γEnac, Dra, Ae1, Nhe3, and Nherf1 showed circadian variation with maximal expression at circadian time 12, i.e., at the beginning of the subjective night. The peak γEnac expression coincided with the rise in plasma aldosterone. Restricted feeding phase advanced the expression of Dra, Ae1, Nherf, and γEnac and decreased expression of Atp1a1. The genes Atp1b1, Cftr, αEnac, βEnac, Nkcc1, and Kcc1 did not show any diurnal variations in mRNA levels. A low-salt diet upregulated the expression of βEnac and γEnac during the subjective night but did not affect expression of αEnac. Similarly, colonic electrogenic Na(+) transport was much higher during the subjective night than the subjective day. These findings indicate that the transporters and channels operating in NaCl absorption undergo diurnal regulation and suggest a role of an intestinal clock in the coordination of colonic NaCl absorption.
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Affiliation(s)
- M Soták
- Institute of Physiology, Academy of Sciences of the Czech Republic, Prague, Czech Republic
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