Ghrelin/Obestatin Ratio as a Potential Mediator for Food Intake and Fat Distribution among a Sample of Obese Egyptian Children

Background: Ghrelin and Obestatin are two hormonal peptides convey to central nervous system information concerning nutritional status and energy stores.

Objective: Assessment of Ghrelin/Obestatin ratio relation to food intake and fat distribution in obese children.

Methods: Study was cross-sectional case-control, comprised 60 Egyptian obese children aged (6-<12y) of both sexes with body mass index(BMI) ≥ 95^th percentile, and 31 healthy (age-sex matched)as controls, collected from "Visceral Obesity and Growth Disturbances Unit" National Research Centre. All children were subjected to Food Intake questionnaire for 24-hours with average dietary recall of 3 days, food frequency items and any snacks taken between meals. Anthropometric assessment (Weight, Height; Waist, Hip circumferences; Calculated BMI, Waist/ hip, Waist/ height; Triceps, Bicepes, Subscapular, Suprailiac and Abdominal skin fold thickness and Laboratory investigations (Serum Ghrelin, Obestatin, fasting Glucose, fasting Insulin, Ghrelin/Obestatin ratio, HOMA; and Lipid profile).

Results: Obese children had tendency for central obesity.In obese group: Ghrelin showed significant positive correlation with serum level of Glucose, total Energy, protein, Fat, Saturated and Monounsaturated Fatty acids intake. In control group: Obestatin had significant positive correlations with total Energy, total Fat and Saturated Fatty acids intake; while, Ghrelin/Obestatin ratio had significant negative correlation with total Energy intake. Ghrelin did not show any statistically significant correlations with fat distribution among the studied groups but on the other hand, Obestatin and Ghrelin/Obestatin ratio showed significant association with Subscapular skin fold thickness (central subcutaneous fat).Step wise linear regression analysis showed that total energy intake is a highly significant predictor for 19%, Fat energy intake for 14% of changes occurring in Ghrelin, while total energy intake responsible for 4% of changes occurring in Ghrelin/Obestatin ratio.

Conclusion: Ghrelin /Obestatin ratio was negatively correlated with total energy intake. It showed significant association with central subcutaneous fat. Ghrelin/Obestatin ratio may have a role in the etiology and pathophysiology of obesity.