Relationship between Growth Hormone and Cytokines in Short Children Undergoing Growth Hormone Stimulation Testing

Background: The relationship between growth hormone (GH) and cytokines remains unclear. Several studies have suggested that GH increases tumor necrosis factor (TNF)-α production in both children and adults. However, a number of studies have demonstrated a negative correlation between GH and TNF α. The aim of this study is to explore the relationship between endogenous GH secretion and certain pro and anti-inflammatory cytokines in short children undergoing GH stimulation testing for evaluation for GH deficiency. Methods: Plasma growth hormone, TNF α, CRP, IL-6, IL1-β, IL-4 and IL-10 levels are obtained at baseline and every 30 minutes for 150 minutes following two provocative agents (clonidine, and either arginine or glucagon). Results: Among the 23 children, 7 are found to be GH deficient. No significant differences in baseline TNF α levels are found between GH deficient and GH sufficient children. No correlation is identified between TNF α levels and GH levels during stimulation testing. Furthermore, no relationship is found between GH and pro-inflammatory cytokines or GH and anti-inflammatory cytokines. Conclusion: Our results do not demonstrate an acute relationship between endogenous GH secretion and the cytokines examined.