Ghrelin Enhances Appetite and Increases Food Intake in Humans

Abstract

Ghrelin is a recently identified endogenous ligand for the growth hormone secretagogue receptor. It is synthesized predominantly in the stomach and found in the circulation of healthy humans. Ghrelin has been shown to promote increased food intake, weight gain and adiposity in rodents. The effect of ghrelin on appetite and food intake in man has not been determined. We investigated the effects of intravenous ghrelin (5.0 pmol/kg/min) or saline infusion on appetite and food intake in a randomised double-blind cross-over study in nine healthy volunteers. There was a clear-cut increase in energy consumed by every individual from a free-choice buffet (mean increase 28 ± 3.9%, p<0.001) during ghrelin compared with saline infusion. Visual analogue scores for appetite were greater during ghrelin compared to saline infusion. Ghrelin had no effect on gastric emptying as assessed by the paracetamol absorption test. Ghrelin is the first circulating hormone demonstrated to stimulate food intake in man. Endogenous ghrelin is a potentially important new regulator of the complex systems controlling food intake and body weight. _____________________________________________________________________________________________________

Peripherally Circulating Ghrelin Does Not Mediate Alcohol‐Induced Reward and Alcohol Intake in Rodents

“…The present findings support a physiological role for circulating ghrelin in food intake, appetite as well as meal initiation (Egecioglu et al, 2011; Wren et al, 2000, 2001a,b), as we here showed that NOX‐B11‐2 reduced food intake in alcohol‐drinking rats. Supportively, previous studies show that NOX‐B11‐2 decreased food intake in rodents via ghrelin‐dependent mechanisms (Kobelt et al., 2006; Shearman et al., 2006).…”

“…Human studies show that ghrelin increases the sensation of hunger and appetite. (Wren et al., 2001a). The plasma levels of ghrelin rise preprandially and fall postprandially in humans as well as in rodents, implying that ghrelin induces meal initiation (for review, see Egecioglu et al., 2011).…”

Expression and function of the ghrelin axis, including a novel preproghrelin isoform, in human breast cancer tissues and cell lines

“…Its actions include a role in appetite regulation and obesity (Wren et al 2001), while the evidence regarding its influence on adipogenesis is contradictory (Zhang et al 2004a). Energy homeostasis is directly associated with reproductive function and the importance of ghrelin in a range of reproductive processes, including steroid hormone regulation and embryo development, has recently been demonstrated (Barreiro & Tena-Sempere 2004).…”

Cationic pullulan nanogel as a safe and effective nasal vaccine delivery system for respiratory infectious diseases

“…34 , 35 For example, a vaccine formulation has been created in which PspA is fused as a carrier protein to recombinant ghrelin, a peptide hormone produced in the stomach (ghrelin–PspA). Because ghrelin increases appetite (and thus increases food intake) and decreases energy expenditure, 36 antibody against ghrelin theoretically could restore the balance between food intake and energy expenditure, leading to homeostasis and preventing obesity. Indeed, nasal administration of ghrelin–PspA with cyclic diguanosine monophosphate as an adjuvant increased antigen-specific serum IgG levels and decreased body weight in mice with diet-induced obesity.…”