Interactions between the growth hormone and cytokines - A review

Numerous reports on the interactions between the immune and endocrine systems, especially growth hormone axis, can be found in the literature. Growth hormone acts mainly indirectly through insulin-like growth factor-1, which stimulates the growth and development processes, metabolism of lipids, proteins, and carbohydrates, and it also has a modulating effect on the cells of the immune system. Several studies have been conducted on the influence of growth hormone therapy on the immunological parameters in children and adults with and without growth hormone deficiency. However, there have been no definite results and some of them have been even contradictory. Some studies have suggested that administration of growth hormone increases the production of tumor necrosis factor and certain pro- and anti-inflammatory cytokines; whereas other studies have demonstrated the lack of correlation between growth hormone and interleukins. The aim of this paper was to evaluate the available literature on the interaction between growth hormone and TNF-α, pro-inflammatory (IL-1β, IL-2, IL-6) and anti-inflammatory (IL-4, IL-10) interleukins.