The majority of in vivo studies showed a null or inverse association of ghrelin with risk and progression of most cancers , suggesting that ghrelin/ghrelin-receptor agonist treatment may have a favorable safety profile to use for cancer cachexia .
Ghrelin is a hormone with multiple physiologic functions , including promotion of growth hormone release , stimulation of appetite and regulation of energy homeostasis .
Treatment with ghrelin/ghrelin-receptor agonists is a prospect i ve therapy for disease-related cachexia and malnutrition .
In vitro studies have shown high expression of ghrelin in cancer tissue , although its role including its impact in cancer risk and progression has not been established .
Physiologic concentrations of exogenously infused ghrelin reduces insulin secretion without affecting insulin sensitivity in healthy humans.
BACKGROUND Infusion of ghrelin to supraphysiologic levels inhibits glucose-stimulated insulin secretion , reduces insulin sensitivity , and worsens glucose tolerance in humans . OBJECTIVE The purpose of this study was to determine the effects of lower doses of ghrelin on insulin secretion and insulin sensitivity in healthy men and women . METHODS Acyl ghrelin ( 0.2 and 0.6 nmol kg(-1 ) h(-1 ) ) or saline was infused for 225 minutes in 16 healthy subjects on 3 separate occasions in r and omized order . An i.v . glucose tolerance test was performed , and the insulin sensitivity index ( SI ) was derived from the minimal model . Insulin secretion was measured as the acute insulin response to glucose ( AIRg ) and the disposition index was computed as AIRg × SI . RESULTS Ghrelin infusions at 0.2 and 0.6 nmol kg(-1 ) h(-1 ) raised steady-state plasma total ghrelin levels 2.2- and 6.1-fold above fasting concentrations . Neither dose of ghrelin altered fasting plasma insulin , glucose , or SI , but both doses reduced insulin secretion compared with the saline control , computed either as AIRg ( 384 ± 75 and 354 ± 65 vs 520 ± 110 pM · min [ mean ± SEM ] , respectively ; P < .01 for both low- and high-dose vs saline ) or disposition index ( 2238 ± 421 and 2067 ± 396 vs 3339 ± 705 , respectively ; P < .02 for both comparisons ) . The high-dose ghrelin infusion also decreased glucose tolerance . CONCLUSIONS Ghrelin infused to levels occurring in physiologic states such as starvation decreases insulin secretion without affecting insulin sensitivity . These findings are consistent with a role for endogenous ghrelin in the regulation of insulin secretion and suggest that ghrelin antagonism could improve β-cell function
The majority of in vivo studies showed a null or inverse association of ghrelin with risk and progression of most cancers , suggesting that ghrelin/ghrelin-receptor agonist treatment may have a favorable safety profile to use for cancer cachexia .
Ghrelin is a hormone with multiple physiologic functions , including promotion of growth hormone release , stimulation of appetite and regulation of energy homeostasis .
Treatment with ghrelin/ghrelin-receptor agonists is a prospect i ve therapy for disease-related cachexia and malnutrition .
In vitro studies have shown high expression of ghrelin in cancer tissue , although its role including its impact in cancer risk and progression has not been established .