Neuroendocrine-immune correlates of circadian physiology: studies in experimental models of arthritis, ethanol feeding, aging, social isolation, and calorie restriction

Endocrine. 2007 Aug;32(1):1-19. doi: 10.1007/s12020-007-9009-y. Epub 2007 Sep 29.


Virtually all neuroendocrine and immunological variables investigated in animals and humans display biological periodicity. Circadian rhythmicity is revealed for every hormone in circulation as well as for circulating immune cells, lymphocyte metabolism and transformability, cytokines, receptors, and adhesion molecules. Clock genes, notably the three Period (Per1/Per2/Per3) genes and two Cryptochrome (Cry1/Cry2) genes, are present in immune and endocrine cells and are expressed in a circadian manner in human cells. This review discusses the circadian disruption of hormone release and immune-related mechanisms in several animal models in which circulating cytokines are modified including rat adjuvant arthritis, social isolation in rats and rabbits and alcoholism, the aging process and calorie restriction in rats. In every case the experimental manipulation used perturbed the temporal organization by affecting the shape and amplitude of a rhythm or by modifying the intrinsic oscillatory mechanism itself.

Publication types

  • Review

MeSH terms

  • Aging / immunology
  • Aging / physiology
  • Alcohol Drinking / immunology
  • Alcohol Drinking / physiopathology
  • Animals
  • Arthritis / immunology
  • Arthritis / physiopathology
  • Caloric Restriction
  • Circadian Rhythm / immunology
  • Circadian Rhythm / physiology*
  • Disease Models, Animal
  • Immune System / physiology*
  • Inflammation / immunology
  • Inflammation / physiopathology
  • Neurosecretory Systems / physiology*
  • Social Isolation