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Hsieh CY, Tsai PW, Tomioka Y, Matsumoto Y, Akiyama Y, Wang CC, Tayo LL, Lee CJ. Chronopharmacology of diuresis via metabolic profiling and key biomarker discovery of the traditional Chinese prescription Ji-Ming-San using tandem mass spectrometry in rat models. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 124:155260. [PMID: 38176264 DOI: 10.1016/j.phymed.2023.155260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/14/2023] [Accepted: 12/04/2023] [Indexed: 01/06/2024]
Abstract
BACKGROUND Ji-Ming-Shan (JMS) is a traditional prescription used for patients with rheumatism, tendons swelling, relief of foot pain, athlete's foot, diuresis, gout. Although many studies have investigated the active compounds in each herb, the functional mechanism behind its therapeutic effect remains unclear. STUDY DESIGN Metabolic cages for sample collection. The serum components obtained from the experimental animals were analyzed using LC-MS/MS. Furthermore, cross-analysis using the software MetaboAnalyst and Venn diagrams were used to investigate chronopharmacology of JMS in the animal models. PURPOSE The aim of this study is to analyze the diuretic effects of JMS and to explore their chronopharmacology involved in organ regulation through four-quarter periods from serum samples of rat models. METHODS Metabolic cages were used for collecting the urine samples and PocketChem UA PU-4010, Fuji DRI-CHEM 800 were used to examine the urine biochemical parameters. The serum components were identified through ultra-performance liquid chromatography-quadrupole time-of-flight (UPLC-Q-TOF) with a new developed method. Cross analysis, Venn diagram, MetaboAnalyst were used to investigate the key biomarker and major metabolism route with the oral administration of the drug. RESULT JMS significantly changed the 6 h urine volume with no observed kidney toxicity. Urine pH value ranges from 7.0 to 7.5. The chronopharmacology of JMS diuresis activity were 0-6 and 6-12 groups. UPLC-Q-TOF analyses identified 243 metabolites which were determined in positive mode and negative mode respectively. With cross analysis in the Venn diagram, one key biomarker naringenin-7-O-glucoside has been identified. Major metabolic pathways such as 1: Glycerophospholipid metabolism, 2: Primary bile acid biosynthesis, 3: Sphingolipid metabolism, 4: Riboflavin metabolism, 5: Linoleic acid metabolism, 6: Butanoate metabolism. CONCLUSION JMS significantly changed the urine output of animals in the 0-6 and 6-12 groups. No change in urine pH was observed and also kidney toxicity. A new UPLC-Q-TOF method was developed for the detection of the metabolites of JMS after oral administration. The cross analysis with Venn diagram and identified the key biomarker of JMS namely naringenin-7-O-glucoside. The results showed that six major pathways are involved in the gastrointestinal system and the liver. This study demonstrated the capability of JMS prescription in the regulation of diuresis and identified a key biomarker that is responsible for its therapeutic effect.
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Affiliation(s)
- Cheng-Yang Hsieh
- Program in Clinical Drug Development of Herbal Medicine, College of Pharmacy, Taipei Medical University, Postal address: Teaching & research building, 250 Wu-Hsing Street, Taipei 110, Taiwan; Laboratory of Oncology, Pharmacy Practice and Sciences, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai Japan
| | - Po-Wei Tsai
- Department of Medical Science Industries, College of Health Sciences, Chang Jung Christian University, Tainan 711, Taiwan
| | - Yoshihisa Tomioka
- Laboratory of Oncology, Pharmacy Practice and Sciences, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai Japan
| | - Yotaro Matsumoto
- Laboratory of Oncology, Pharmacy Practice and Sciences, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai Japan
| | - Yasutoshi Akiyama
- Laboratory of Oncology, Pharmacy Practice and Sciences, Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai Japan
| | - Ching-Chiung Wang
- Program in Clinical Drug Development of Herbal Medicine, College of Pharmacy, Taipei Medical University, Postal address: Teaching & research building, 250 Wu-Hsing Street, Taipei 110, Taiwan; Graduate Institute of Pharmacognosy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan; Traditional Herbal Medicine Research Center, Taipei Medical University Hospital, Taipei 110, Taiwan; School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan
| | - Lemmuel L Tayo
- School of Chemical, Biological, Materials Engineering and Sciences, Mapúa University, Intramuros, 1002 Metro Manila, Manila, Philippines; Department of Biology, School of Medicine and Health Sciences Mapua University, Makati, Philippines
| | - Chia-Jung Lee
- Program in Clinical Drug Development of Herbal Medicine, College of Pharmacy, Taipei Medical University, Postal address: Teaching & research building, 250 Wu-Hsing Street, Taipei 110, Taiwan; Graduate Institute of Pharmacognosy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan; Traditional Herbal Medicine Research Center, Taipei Medical University Hospital, Taipei 110, Taiwan.
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Rukmini AV, Jos AM, Yeo SC, Lee N, Mo D, Mohapatra L, Karamchedu S, Gooley JJ. Circadian regulation of breath alcohol concentration. Sleep 2021; 44:6030924. [PMID: 33305816 DOI: 10.1093/sleep/zsaa270] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 11/11/2020] [Indexed: 11/13/2022] Open
Abstract
STUDY OBJECTIVES The role of the circadian clock in regulating blood/breath alcohol levels after consuming alcohol is uncertain. Our goal was to evaluate the degree to which the circadian system regulates breath alcohol concentration (BrAC) pharmacokinetic parameters. METHODS Twenty healthy adults aged 21-30 years took part in a 4-day laboratory study. A 40-h constant routine procedure was used to assess circadian rhythms. Every 4 h, participants were given a fixed oral dose of alcohol with breathalyzer measurements taken every 5 min to construct BrAC curves. Sinusoidal models were used to test for circadian variation of the peak BrAC, the time to reach peak BrAC, the absorption rate, the elimination rate, and the time for BrAC to return to zero after alcohol was ingested. RESULTS A significant circadian rhythm was detected for group-averaged peak BrAC values and the time for BrAC to return to zero, but not other BrAC variables. Peak BrAC values were lowest in the evening near the peak of the core body temperature rhythm and nadir of the salivary cortisol rhythm. Peak BrAC values increased during the night and reached their highest levels in the morning and afternoon. The time needed for BrAC to return to zero was also longest in the late morning and afternoon. CONCLUSION The circadian system modulates some BrAC pharmacokinetic parameters. In normally entrained individuals, taking the same oral dose of alcohol at different times of day can result in different BrAC responses. These findings have potential implications for alcohol-related accidents and alcohol toxicity.
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Affiliation(s)
- A V Rukmini
- Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Anna Mini Jos
- Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Sing-Chen Yeo
- Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Noel Lee
- Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Di Mo
- Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Litali Mohapatra
- Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Swathy Karamchedu
- Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
| | - Joshua J Gooley
- Neuroscience and Behavioral Disorders Program, Duke-NUS Medical School, Singapore
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Abstract
The objective of this review is to provide an overview of intermittent fasting regimens, summarize the evidence on the health benefits of intermittent fasting, and discuss physiological mechanisms by which intermittent fasting might lead to improved health outcomes. A MEDLINE search was performed using PubMed and the terms "intermittent fasting," "fasting," "time-restricted feeding," and "food timing." Modified fasting regimens appear to promote weight loss and may improve metabolic health. Several lines of evidence also support the hypothesis that eating patterns that reduce or eliminate nighttime eating and prolong nightly fasting intervals may result in sustained improvements in human health. Intermittent fasting regimens are hypothesized to influence metabolic regulation via effects on (a) circadian biology, (b) the gut microbiome, and (c) modifiable lifestyle behaviors, such as sleep. If proven to be efficacious, these eating regimens offer promising nonpharmacological approaches to improving health at the population level, with multiple public health benefits.
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Affiliation(s)
- Ruth E Patterson
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093; .,Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, California 92093
| | - Dorothy D Sears
- Moores Cancer Center, University of California, San Diego, La Jolla, California 92093; .,Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, California 92093.,Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Diego, La Jolla, California 92093
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Sadeghirad B, Motaghipisheh S, Kolahdooz F, Zahedi MJ, Haghdoost AA. Islamic fasting and weight loss: a systematic review and meta-analysis. Public Health Nutr 2014; 17:396-406. [PMID: 23182306 PMCID: PMC10282472 DOI: 10.1017/s1368980012005046] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 06/20/2012] [Accepted: 07/30/2012] [Indexed: 11/07/2022]
Abstract
OBJECTIVE Studies on the effects of Ramadan fasting on weight changes have been contradictory. We brought together all published data to comprehensively examine the effects in a systematic review and meta-analysis. DESIGN Relevant studies were obtained through searches of PubMed and CINAHL and by independent screening of reference lists and citations without any time restriction. All searches were completed between October and November 2011. SETTING Changes in body weight during and after Ramadan were extracted from thirty-five English-language studies and were meta-analysed. Most of the studies were conducted in West Asia (n 19); the remainder were conducted in Africa (n 7), East Asia (n 3) and North America/Europe (n 4). SUBJECTS Healthy adults. RESULTS Fasting during Ramadan resulted in significant weight loss (-1·24 kg; 95% CI -1·60, -0·88 kg). However, most of the weight lost was regained within a few weeks and only a slight decrease in body weight was observed in the following weeks after Ramadan compared with that at the beginning of Ramadan. Weight loss at the end of Ramadan was significant in both genders (-1·51 kg for men and -0·92 kg for women); but again the weight loss lasted no longer than 2 weeks after Ramadan. Weight loss during Ramadan was greater among Asian populations compared with Africans and Europeans. CONCLUSIONS Weight changes during Ramadan were relatively small and mostly reversed after Ramadan, gradually returning to pre-Ramadan status. Ramadan provides an opportunity to lose weight, but structured and consistent lifestyle modifications are necessary to achieve lasting weight loss.
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Affiliation(s)
- Behnam Sadeghirad
- Kerman Neuroscience Research Center, University of Medical Sciences, Kerman, Islamic Republic of Iran
| | - Shahrzad Motaghipisheh
- Research Center for Modeling in Health, University of Medical Sciences, Avicenna Ave., Jahad Blvd, Postal Code 7619813159, Kerman, Islamic Republic of Iran
| | - Fariba Kolahdooz
- Aboriginal & Global Health Research Group, Department of Medicine, University of Alberta, Edmonton, Canada
| | - Mohammad J Zahedi
- Physiology Research Center, Internal Medicine Department, University of Medical Sciences, Kerman, Islamic Republic of Iran
| | - Ali A Haghdoost
- Research Center for Modeling in Health, University of Medical Sciences, Avicenna Ave., Jahad Blvd, Postal Code 7619813159, Kerman, Islamic Republic of Iran
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
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Stenvers DJ, Jonkers CF, Fliers E, Bisschop PHLT, Kalsbeek A. Nutrition and the circadian timing system. PROGRESS IN BRAIN RESEARCH 2013; 199:359-376. [PMID: 22877675 DOI: 10.1016/b978-0-444-59427-3.00020-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Life on earth has evolved under the daily rhythm of light and dark. Consequently, most creatures experience a daily rhythm in food availability. In this review, we first introduce the mammalian circadian timing system, consisting of a central clock in the suprachiasmatic nucleus (SCN) and peripheral clocks in various metabolic tissues including liver, pancreas, and intestine. We describe how peripheral clocks are synchronized by the SCN and metabolic signals. Second, we review the influence of the circadian timing system on food intake behavior, activity of the gastrointestinal system, and several aspects of glucose and lipid metabolism. Third, the circadian control of digestion and metabolism may have important implications for several aspects of food intake in humans. Therefore, we review the human literature on health aspects of meal timing, meal frequency, and breakfast consumption, and we describe the potential implications of the clock system for the timing of enteral tube feeding and parenteral nutrition. Finally, we explore the connection between type 2 diabetes and the circadian timing system. Although the past decade has provided exciting knowledge about the reciprocal relation between biological clocks and feeding/energy metabolism, future research is necessary to further elucidate this fascinating relationship in order to improve human health.
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Affiliation(s)
- Dirk Jan Stenvers
- Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands.
| | - Cora F Jonkers
- Department of Nutrition, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands
| | - Eric Fliers
- Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands
| | - Peter H L T Bisschop
- Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands
| | - Andries Kalsbeek
- Department of Endocrinology and Metabolism, Academic Medical Center (AMC), University of Amsterdam, Amsterdam, The Netherlands; Hypothalamic Integration Mechanisms, Netherlands Institute for Neuroscience (NIN), An Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), Amsterdam, The Netherlands
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Leatherwood WE, Dragoo JL. Effect of airline travel on performance: a review of the literature. Br J Sports Med 2012; 47:561-7. [PMID: 23143931 DOI: 10.1136/bjsports-2012-091449] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The need for athletes to travel long distances has spurred investigation into the effect of air travel across multiple time zones on athletic performance. Rapid eastward or westward travel may negatively affect the body in many ways; therefore, strategies should be employed to minimise these effects which may hamper athletic performance. In this review, the fundamentals of circadian rhythm disruption are examined along with additional effects of airline travel including jet lag, sleep deprivation, travel at altitude and nutritional considerations that negatively affect performance. Evidence-based recommendations are provided at the end of the manuscript to minimise the effects of airline travel on performance.
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Affiliation(s)
- Whitney E Leatherwood
- Department of Orthopaedic Surgery, Stanford University, Stanford, California 94063-6342, USA
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Reilly T, Waterhouse J. Altered sleep–wake cycles and food intake: The Ramadan model. Physiol Behav 2007; 90:219-28. [PMID: 17081572 DOI: 10.1016/j.physbeh.2006.09.004] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2006] [Accepted: 09/04/2006] [Indexed: 12/28/2022]
Abstract
In this review the effects of diurnal fasting on normal physiological processes are considered. Ramadan is placed in a circadian context, food and fluid ingestion being displaced to the pre-sunrise and post-sunset hours. Over the holy month, negative energy balance is often experienced, though this deficit is not a universal finding. Responses to exercise during the day show influences consistent with hypohydration and an increased reliance on fat as a source of fuel for exercise. Muscle performance and psychomotor performance are impaired as the month of fasting progresses but it is not clear how circadian rhythms in responses to activity are altered. For some measures at rest there is a reduction in amplitude and a delay in acrophase. Health-related benefits are reflected in a rise in high-density lipoprotein cholesterol and individuals with predispositions for coronary heart disease are not at increased risk of cardiovascular disorders due to fasting. The physiological adjustments during the month have some similarities to the disturbances in circadian rhythms experienced in different circumstances. The Ramadan model provides an alternative to those for ageing, nocturnal shift-work and time-zone transitions in understanding the links between behaviour and endogenous circadian rhythms.
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Affiliation(s)
- Thomas Reilly
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Henry Cotton Campus, 15-21 Webster Street, Liverpool, L3 2ET, United Kingdom.
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Psychophysiological States: the Ultradian Dynamics of Mind–Body Interactions. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2007. [DOI: 10.1016/s0074-7742(07)80001-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Youan BBC. Chronopharmaceutics: gimmick or clinically relevant approach to drug delivery? J Control Release 2004; 98:337-53. [PMID: 15312991 DOI: 10.1016/j.jconrel.2004.05.015] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2004] [Accepted: 05/25/2004] [Indexed: 10/26/2022]
Abstract
Due to advances in chronobiology, chronopharmacology, and global market constraints, the traditional goal of pharmaceutics (e.g. design drug delivery systems with a constant drug release rate) is becoming obsolete. However, the major bottleneck in the development of drug delivery systems that match the circadian rhythm (chronopharmaceutical drug delivery systems: ChrDDS) may be the availability of appropriate technology. The last decade has witnessed the emergence of ChrDDS against several diseases. The increasing research interest surrounding ChrDDS may lead to the creation of a new sub-discipline in pharmaceutics known as chronopharmaceutics. This review introduces the concept of chronopharmaceutics, addresses theoretical/formal approaches to this sub-discipline, underscores potential disease-targets, revisits existing technologies and examples of ChrDDS. Future development in chronopharmaceutics may be made at the interface of other emerging disciplines such as system biology and nanomedicine. Such novel and more biological approaches to drug delivery may lead to safer and more efficient disease therapy in the future.
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Affiliation(s)
- Bi-Botti C Youan
- Department of Pharmaceutical Sciences, School of Pharmacy, Texas Tech University Health Sciences Center School of Pharmacy, Amarillo 1300, Coulter, TX 79106, USA.
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Abstract
Pharmacokinetic interactions between food and orally administered drugs involve changes mainly in the absorption and metabolism of a drug, and may have clinical implications. Such interactions, in particular, may be of major clinical significance for cancer chemotherapy since the majority of anticancer agents are toxic, have a low therapeutic index and are administered long term, most often in combination with other cytotoxic agents. The purpose of this review is to compare the pharmacokinetic profiles of various anticancer drugs, including chemopreventive agents that have been examined previously in fasted and fed conditions, and to discuss the underlying basis/mechanisms of food effect in light of a drug's physicochemical and pharmacokinetic properties. Clinical pharmacokinetic parameters such as maximum concentration, area under the concentration-time curve, time to maximum concentration and half-life for each drug are compared in fasted and fed states, and specific dietary recommendations are summarised accordingly. In addition, the effects of food on the metabolite kinetics and pharmacodynamic responses, and the potential role of food effect in the modulation of oral biovariability and multidrug resistance have been extensively discussed. Overall, this comprehensive pharmacokinetic analysis indicates that a broad spectrum of food effects is seen among anticancer agents because of diverse factors regulating each drug's oral bioavailability and its interactions with food. The consideration of such effects is important, as it could lead to more rational pharmacological monitoring and possibly improve the oral chemotherapy of cancer in children, adults and the elderly.
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Affiliation(s)
- Brahma N Singh
- Department of Pharmacy and Administrative Sciences, College of Pharmacy and Allied Health Professions, St John's University, Jamaica, New York 10591, USA.
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Abstract
The circadian changes in absorption, tissue distribution and elimination of amitriptyline after single intravenous (i.v.) and intragastric (i.g.) administration, as well as the differences in pharmacokinetic profile after multiple i.g. administration (at 10:00 and 22:00 h) during a 12 h dosing interval, were investigated. The circadian changes of pharmacokinetic parameters of amitriptyline such as AUC (serum and tissues), clearance (i.v. and i.g.), volume of distribution, biological half-life and bioavailability were estimated. Acrophases for clearance appeared between 19:00 and 21:00 h; the bioavailability was highest during the dark phase at around 04:00 h. Higher values of AUC in serum were observed at the beginning of the light phase. A circadian rhythm of tissue distribution (AUC, K(D)) of amitriptyline with acrophase in the dark phase was observed for brain (12 h period), lung and liver (24 h), but not for heart or kidney. After single (i.v. and i.g.) amitriptyline administration, concentrations of its major metabolite, nortriptyline, were negligible; however, after ten doses, nortriptyline serum and tissue levels were similar to the concentrations of the parent drug with higher values during the day (light phase).
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Affiliation(s)
- A Rutkowska
- Department of Toxicology, School of Medicine, Jagiellonian University, Kraków, Poland.
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Abstract
The concept of chronopharmacology has significant implications for drug delivery systems. Age and illness put the elderly at greater risk for adverse drug effects, and nurses caring for the elderly have a challenging opportunity to measurably improve the quality of their care by applying chronotherapeutic concepts. Pharmacologic chronotherapy is a developing science that holds much hope for increasing the effectiveness of drug therapy and for reducing the incidence of toxic drug reactions. Nurses who are aware of the principles on which chronotherapy is based are in a unique position to improve the effectiveness of pharmacotherapy for all clients. However, appropriate timing of medications is especially important among elderly clients whose physiological processes are altered or changed by age and chronic illness. In this article, the basis of chronotherapy is discussed, and several therapeutic applications are identified.
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Waterhouse J, Minors D, Atkinson G, Benton D. Chronobiology and meal times: internal and external factors. Br J Nutr 1997; 77 Suppl 1:S29-38. [PMID: 9155492 DOI: 10.1079/bjn19970102] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Although homeostatic mechanisms remain of utmost importance, rhythmic changes are present also. The main ones have a period of 24 h (circadian) or about 2-3 h (ultradian). Circadian rhythms are derived from a body clock, found in the base of the brain, and from the pattern of our sleep-wake cycle, including activity and meal times. These rhythms promote the regular changes between an active wake period and a recuperative sleep period. Ultradian rhythms are also widespread and reflect external (lifestyle) and internal factors. The internal factors include biochemical need and some sort of oscillator; but details of how many oscillators, and exactly where they are, remain to be established. Food intake, appetite, digestion and metabolism have been shown to illustrate these principles. Moreover, these principles become important when special circumstances exist as far as meal times are concerned; the particular difficulties of night workers is a good example.
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Affiliation(s)
- J Waterhouse
- School of Human Sciences, Liverpool John Moores University
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Abstract
There is a fascinating and exceedingly important area of medicine that most of us have not been exposed to at any level of our medical training. This relatively new area is termed chronobiology; that is, how time-related events shape our daily biologic responses and apply to any aspect of medicine with regard to altering pathophysiology and treatment response. For example, normally occurring circadian (daily cycles, approximately 24 hours) events, such as nadirs in epinephrine and cortisol levels that occur in the body around 10 PM to 4 AM and elevated histamine and other mediator levels that occur between midnight and 4 AM, play a major role in the worsening of asthma during the night. In fact, this nocturnal exacerbation occurs in the majority of asthmatic patients. Because all biologic functions, including those of cells, organs, and the entire body, have circadian, ultradian (less than 22 hours), or infradian (greater than 26 hours) rhythms, understanding the pathophysiology and treatment of disease needs to be viewed with these changes in mind. Biologic rhythms are ingrained, and although they can be changed over time by changing the wake-sleep cycle, these alterations occur over days. However, sleep itself can adversely affect the pathophysiology of disease. The non-light/dark influence of biologic rhythms was first described in 1729 by the French astronomer Jean-Jacques de Mairan. Previously, it was presumed that the small red flowers of the plant Kalanchoe bloss feldiuna opened in the day because of the sunlight and closed at night because of the darkness. When de Mairan placed the plant in total darkness, the opening and closing of the flowers still occurred on its intrinsic circadian basis. It is intriguing to think about how the time of day governs the pathophysiology of disease. On awakening in the morning, heart rate and blood pressure briskly increase, as do platelet aggregability and other clotting factors. This can be linked to the acrophase (peak event) of heart attacks. During the afternoon we hit our best mental and physical performance, which explains why most of us state that "I am not a morning person." Even the tolerance for alcohol varies over the 24-hour cycle, with best tolerance around 5 pm (i.e. "Doctor, I only have a couple of highballs before dinner"). Thus, all biologic functions, from those of the cell, the tissue, the organs, and the entire body, run on a cycle of altering activity and function.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- M Kraft
- Department of Medicine, National Jewish Center for Immunology and Respiratory Medicine, University of Colorado Health Sciences Center, Denver, USA
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Abstract
Lack of much interest by the pharmaceutical industry to venture into development of new antitrypanosomal drugs has been a major stimulus to an intensification of research into the few existing drugs. Those indicated for animal trypanosomiasis include: isometamidium, homidium and diminazene, used primarily against Trypanosoma congolense, T. vivax and T. brucei; and quinapyramine, mainly indicated for use against T. evansi infections. A great deal of research effort has focused on development of pharmacological and parasitological methodologies, which have considerably advanced our understanding on the efficacy, resistance, disposition and toxicological mechanisms of these drugs. While a clinical breakthrough has been made in the recent past, in the field of chemotherapy of T. evansi infections by the introduction of a new arsenic compound, melarsenoxide cysteamine, chemotherapy of T. simiae infections in pigs still remains a major challenge because the existing drugs are either ineffective or too toxic for economic use. Further research into the existing drugs is a prerequisite for their optimal usage in the overall effort of improving animal health and productivity through control of trypanosomiasis.
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Affiliation(s)
- L D Kinabo
- Department of Veterinary Physiology, Biochemistry, Pharmacology and Toxicology, Sokoine University Morogoro, Tanzania
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