Leptin concentrations during oral glucose tolerance test (OGTT) in obese and normal weight women

Abstract

OBJECTIVE: To examine possible changes of leptin concentrations after the acute administration of glucose orally (OGTT). DESIGN: Seventy-®ve grams of glucose were administered per os in one group of obese and normal weight individuals and concentrations of glucose, insulin and leptin were measured at 0, 30, 60, 90 and 120 min. In an age matched control group of individuals with similar BMI water was given and leptin concentrations were measured before and after 30, 60, 90 and 120 min. SUBJECTS: Twenty-seven obese women aged 34 AE 1.57 y with BMI 37.1 AE 0.8 kgam 2 and 16 normal weight women, aged 32 AE 1.13 y with BMI 23.6 AE 0.3 kgam 2 formed the experimental group, while 10 obese and 10 normal weight females with similar age and BMI were used as controls. MEASUREMENTS: Weight, height, BMI, body fat, glucose, insulin and leptin at baseline and during OGTT. Variations of the above parameters were calculated from the area under the curve (AUC). RESULTS: Fasting leptin concentrations and AUC were higher in obese than in normal weight women. In obese women, leptin increased signi®cantly in comparison to its basal concentrations 30 and 60 min after the glucose loading. Insulin was also increased, as expected. No correlation was found between insulin and leptin concentrations after glucose loading. Basal concentrations of leptin did not correlate with those of glucose and insulin. No changes in leptin concentrations were found in normal weight women after OGTT. However, a signi®cant positive correlation was found between insulin and basal leptin. Finally, leptin concentrations did not change in obese and normal weight controls after water administration. CONCLUSION: A signi®cant increase in leptin concentrations was found 30 and 60 min after glucose loading in obese individuals. No such increase was found in normal-weight women.

Perioperative Changes in Circulating Leptin Levels in Women Undergoing Total Abdominal Hysterectomy.

“…Our observation agrees with a previous report [14], indicating that basal leptin levels were not correlate with those of glucose. No significant changes in leptin levels were found in normal weight women after glucose administration [14]. There is evidence that surgical stress increases fasting blood sugar levels [2,15,16].…”

Effect of weight loss with or without orlistat treatment on adipocytokines, inflammation, and oxidative markers in obese women

“…59 Furthermore, hyperinsulinemia is related to the production of free radicals. [60][61][62][63] CRP, and other parameters, such as leptin, resistin, TNF-α, and IL-6, were high in obese women prior to intervention as previously reported by our group.…”

Abnormal glucose tolerance is associated with diminished postload change in leptin levels in women

“…This observation corresponds to our univariate negative association with HOMA insulin sensitivity. In other studies significant differences were found between obese and non-obese participants such that the latter group had no change while the former showed an increase in serum leptin levels during an OGTT [12,14]. Although we found a decrease in healthy subjects and no change in glucose intolerant women, these finding are not inconsistent with those of other studies which may be confounded by other factors (i.e.…”