Cited by 124Circadian rhythm and melatoninSleep and Work-Related FatigueDietary Effects on Health

Effects of the endogenous clock and sleep time on melatonin, insulin, glucose and lipid metabolism

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Morgan, L, Arendt, J, Owens, D, Folkard, S, Hampton, S, Deacon, S, English, J, Ribeiro, D +1 more·1998·Journal of Endocrinology

Abstract

This study was undertaken to determine whether the internal clock contributes to the hormone and metabolic responses following food, in an experiment designed to dissociate internal clock effects from other factors. Nine female subjects participated. They lived indoors for 31 days with normal time cues, including the natural light: darkness cycle. For 7 days they retired to bed from 0000 h to 0800 h. They then underwent a 26-h 'constant routine' (CR) starting at 0800 h, being seated awake in dim light with hourly 88 Kcal drinks. They then lived on an imposed 27-h day (18 h of wakefulness, 9 h allowed for sleep), for a total of 27 days. A second 26-h CR, starting at 2200 h, was completed. During each CR salivary melatonin and plasma glucose, triacylglycerol (TAG), non-essential fatty acids (NEFA), insulin, gastric inhibitory peptide (GIP) and glucagon-like peptide-1 (GLP-1) were measured hourly. Melatonin and body temperature data indicated no shift in the endogenous clock during the 27-h imposed schedule. Postprandial NEFA, GIP and GLP-1 showed no consistent effects. Glucose, TAG and insulin increased during the night in the first CR. There was a significant effect of both the endogenous clock and sleep for glucose and TAG, but not for insulin. These findings may be relevant to the known increased risk of cardiovascular disease amongst shift workers.

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  • Human endogenous circadian rhythms have been observed in glucose, insulin, cortisol, epinephrine, norepinephrine, and leptin.

    “For example, glucose, insulin, cortisol, epinephrine, norepinephrine, and leptin display endogenous circadian variation (Morgan et al., 1998; Scheer et al., 2009, 2010; Shea et al., 2005; Van Cauter et al., 1994; Wehr et al., 2001).”

    From The impact of the circadian timing system on cardiovascular and metabolic function (2012) · cites this paper as Morgan et al., 1998

  • Morgan et al. (1998) found no significant changes in concentrations of glucose, insulin, and triglycerides before and after a 19-day forced desynchrony protocol.

    “Morgan et al. (1998) found no significant changes in the concentrations of glucose, insulin, and triglycerides as measured in two constant routine protocols with small hourly liquid meals, before and after a 19-day forced desynchrony protocol.”

    From The impact of the circadian timing system on cardiovascular and metabolic function (2012) · cites this paper as Morgan et al., 1998

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Research works printed but not linked: 4

  1. Eds S Folkard & TH Monk. New York: John Wiley.
  2. Elliott R, Morgan LM, Tredger JA, Deacon S, Wright J & Marks V 1993 Glucagon-like peptide-1 (7-36) amide and glucose-dependent insulinotropic postprandial and 24-h secretion patterns. Journal of Endocrinology 138 159-166.
  3. Morgan LM 1992 Insulin secretion and the enteroinsular axis. In Nutrient Regulation of Insulin Secretion, pp 1-22. Ed P Flatt. London and Chapel Hill: Portland Press.
  4. Van Cauter E, Shapiro ET, Tillel H & Polonsky KS 1992 Circadian modulation of insulin responses to meals: relationship to cortisol rhythm. American Journal of Physiology 262 E467-E475.

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Authors
Morgan, L., Arendt, J., Owens, D., Folkard, S., Hampton, S., Deacon, S., English, J., Ribeiro, D., & Taylor, K.
Affiliations
  • University of Surrey (GB)
  • Swansea University (GB)
Venue
Journal of Endocrinology
Published
1998-06-01
Volume
157
Issue
3
Pages
443-451
ISSN
  • 0022-0795 (ISSN-L)
  • 1479-6805
OpenAlex
W2156331475
Cited by
124
References
31
Citations by year
2026: 1 · 2025: 2 · 2024: 4 · 2023: 4 · 2022: 8 · 2021: 3 · 2020: 6 · 2019: 10 · 2018: 4 · 2017: 5 · 2016: 5 · 2015: 8 · 2014: 10 · 2013: 2 · 2012: 4
FWCI
0.97
Type
journal article
Language
en
Open access
Locations
  • Journal of Endocrinology (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • British Heart Foundation
  • Medical Research Council
Topics
  • Life Sciences › Neuroscience › Endocrine and Autonomic Systems › Circadian rhythm and melatonin
  • Social Sciences › Psychology › Experimental and Cognitive Psychology › Sleep and Work-Related Fatigue
  • Health Sciences › Medicine › Physiology › Dietary Effects on Health
Keywords
circadian clock, sleep timing, melatonin, insulin, glucose metabolism, lipid metabolism, triglycerides, glucose-dependent insulinotropic polypeptide, glucagon-like peptide-1, postprandial response, constant routine, shift work, cardiovascular risk
MeSH terms
Adult, Biological Clocks, Blood Glucose, Body Temperature Regulation, Eating, Female, Humans, Insulin, Melatonin, Saliva, Sleep, Triglycerides, Work Schedule Tolerance, Postprandial Period, Lipid Metabolism

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