Effects of growth hormone and insulin-like growth factor I on the immune system

Abstract

Growth hormone-releasing hormone (GHRH), growth hormone (GH), prolactin (PRL) and insulin-like growth factor I (IGF-I) are synthesized and secreted by various immunocompetent cells. In addition, GHRH, GH, PRL and IGF-I receptors are expressed on immune cells. Growth hormone, PRL and IGF-I stimulate the proliferation of immunocompetent cells and modulate humoral and cellular immune functions, i.e. immunoglobuline secretion of B cells, thymulin secretion of thymic epithelial cells, natural killer cell activity, phagocytosis, oxidative burst and killing capacity of neutrophils and macrophages. No clinically significant cellular or humoral immunodeficiency has been found in GH-deficient patients. However, several immunological parameters and functions are altered in GH-deficient patients when compared to normal controls. The data available to date indicate that endocrine and pleiotropic para- and autocrine mechanisms of action are involved in a neuropeptide immune network, including GH, PRL and IGF-I as modulators of immune function.

Growth hormone interacts with the Marek's disease virus SORF2 protein and is associated with disease resistance in chicken

“…However, as yet there is no information on the molecular basis of how these proteins interact and how this interaction influences MD resistance. GH is known to modulate the immune response and a variety of direct and indirect influences have been shown (41,42). Higher GH levels activate and stimulate the proliferation of more B and T lymphoctyes both in vitro and in vivo in humans and mammals (61)(62)(63)(64).…”

“…There is growing evidence that GH modulates the immune system in many species (41,42), and it has been reported that the frequency of GH1 alleles change in chicken strains in response to selection for MD resistance (43). To rule out the possibility that the alteration in GH1 allele frequency in chicken strains was caused by random genetic drift, genetic mapping was performed to determine whether GH1 was linked to a previously identified MD QTL (19,20,44).…”

Assessment of immune function after short-term administration of recombinant human growth hormone in healthy young males

“…Other cells do express GH and IGF-I receptors and include B lymphocytes, macrophage, T lymphocytes and granulocytes precursors (Auernhammer & Strasburger, 1995). In GHD patients suffering from hypopituitarism, they demonstrate immunological impairment parameters such as increased basal plasma levels of tumour necrosis factor-(TNF -220%) and IL-6 by 340% (Serri et al, 1999).…”

The Relation between Non-adipose Muscle Fat and Hepatic Steatosis Studied with Localized 1H Magnetic Resonance Spectroscopy (1H MRS) and LC-MS Techniques

“…These hormones, collectively, exert an anabolic and lipolytic effect. Especially, somatropin is a powerful lipolytic-(fat mobilizing) [46], anabolic-(muscle-enhancing) [47], immune system stimulating hormone [48] that also directly influences cholesterol and triacylglycerol levels [49]. Protein also exerts a weak stimulatory effect on insulin, approximately 30% of the effect of carbohydrate on insulin [50].…”