Circulating levels of ghrelin in human fetuses

Abstract

Objective: Ghrelin is a GH secretagog isolated recently from rat stomach and involved in the stimulation of food intake and adiposity in rodents and humans. Moreover, subsequent studies showed that ghrelin is expressed in rat and human placenta, suggesting a possible influence of the peptide on fetal growth. The aim of this study was to evaluate circulating levels of ghrelin in appropriate for gestational age (AGA) or intrauterine growth-restricted (IUGR) fetuses. Subjects and methods: Ghrelin levels between 20 and 39 weeks of gestation were measured in 16 AGA and nine IUGR fetuses in whom blood was collected by cordocentesis performed for prenatal diagnosis of different diseases or during elective cesarean section. In most samples, GH, cortisol and leptin levels were also evaluated. Results are expressed as means^S.D. Differences were tested using the Student's t-test with Welch correction. P , 0.05 was considered significant. Results: All fetuses showed levels of ghrelin in the umbilical venous blood (100^99 pmol/l) that did not correlate with the gestational age or the maternal ghrelin levels. No difference was found between umbilical venous and arterial concentrations, suggesting that fetal tissues are a source of ghrelin. Ghrelin levels in IUGR fetuses were significantly higher than those found in AGA fetuses (176^125 vs 58^44 pmol/l; P , 0.005). Moreover, in samples obtained at birth, ghrelin concentrations correlated negatively with birth weight (P , 0.05). In IUGR fetuses, GH and cortisol concentrations were higher and leptin levels lower than in AGA fetuses, although no significant correlation between these parameters and ghrelin levels was found. Conclusion: The presence of ghrelin in the fetal circulation as well as its increase in IUGR fetuses suggest a role of this peptide during intrauterine development.

Role of ghrelin in reproduction

“…As was the case in the rat, ghrelin expression has been also detected in human placenta (Gualillo et al 2001), and ghrelin has been demonstrated in human fetal circulation (Cortelazzi et al 2003). However, the role, if any, of placental and fetal ghrelin in the regulation of gestational growth and metabolism remains to be fully elucidated.…”

Influence of chronic undernutrition and leptin on GOAT mRNA levels in rat stomach mucosa

“…Also since the ghrelinexpressing cells are located in the mucosa, we assessed GOAT mRNA levels in samples extracted from this source. Furthermore, taking into consideration that ghrelin mRNA levels can be influenced by the age of the animals (Gualillo et al 2001, Cortelazzi et al 2003, we first assessed GOAT mRNA levels in samples from male rats of different ages. We found that GOAT mRNA levels were relatively stable at all the ages studied (Fig.…”

Ghrelin, Nitrite and Paraoxonase/Arylesterase Concentrations in Cement Plant Workers

“…Human ghrelin (hunger hormone) is a novel peptide hormone, which is predominantly synthesized in the stomach (10,12,13), but it is also synthesized in several other tissues including the central nervous system, kidney, heart, parathyroid glands, the small and large intestines, a-cells of the pancreatic islet (14), placenta (15), and salivary gland (16). It sti mulates growth hormone (GH) secretion and acts as a signal for the regulation of food intake, energy expenditure and fat accumulation, and body weight gain (12,17).…”