title: The pathophysiologic roles of interleukin-6 in human disease.
abstract: Interleukin-6, an inflammatory cytokine, is characterized by pleiotropy and redundancy of action. Apart from its hematologic, immune, and hepatic effects, it has many endocrine and metabolic actions. Specifically, it is a potent stimulator of the hypothalamic-pituitary-adrenal axis and is under the tonic negative control of glucocorticoids. It acutely stimulates the secretion of growth hormone, inhibits thyroid-stimulating hormone secretion, and decreases serum lipid concentrations. Furthermore, it is secreted during stress and is positively controlled by catecholamines. Administration of interleukin-6 results in fever, anorexia, and fatigue. Elevated levels of circulating interleukin-6 have been seen in the steroid withdrawal syndrome and in the severe inflammatory, infectious, and traumatic states potentially associated with the inappropriate secretion of vasopressin. Levels of circulating interleukin-6 are also elevated in several inflammatory diseases, such as rheumatoid arthritis. Interleukin-6 is negatively controlled by estrogens and androgens, and it plays a central role in the pathogenesis of the osteoporosis seen in conditions characterized by increased bone resorption, such as sex-steroid deficiency and hyperparathyroidism. Overproduction of interleukin-6 may contribute to illness during aging and chronic stress. Finally, administration of recombinant human interleukin-6 may serve as a stimulation test for the integrity of the hypothalamic-pituitary-adrenal axis.
authors.forename: D A
authors.initials: DA
authors.lastname: Papanicolaou
authors.forename: R L
authors.initials: RL
authors.lastname: Wilder
authors.forename: S C
authors.initials: SC
authors.lastname: Manolagas
authors.forename: G P
authors.initials: GP
authors.lastname: Chrousos
mesh_terms: D000375:Aging / Q000502:physiology; D001327:Autoimmune Diseases / Q000503:physiopathology; D001847:Bone Diseases / Q000503:physiopathology; D004703:Endocrine System / Q000502:physiology; D005260:Female; D006801:Humans; D007107:Immune System / Q000502:physiology; D007249:Inflammation / Q000503:physiopathology; D007378:Interleukins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D008297:Male; D010024:Osteoporosis / Q000503:physiopathology; D014481:United States
chemical_list: D007378:Interleukins