Effect of the orlistat on serum endotoxin lipopolysaccharide and adipocytokines in South Asian individuals with impaired glucose tolerance

Background: Orlistat has been shown to increase adiponectin and reduce progression to type 2 diabetes in obese Caucasians. Some effects of orlistat are thought to be independent of weight loss by altering gut flora and the production of endotoxin lipopolysaccharide (LPS). We studied the effect of dietary treatment with and without orlistat in South Asian individuals with impaired glucose tolerance (IGT) on adiponectin and inflammatory markers including LPS. Methods: South Asian individuals were randomised to either dietary treatment with orlistat or dietary treatment alone. At the end of 12 months, a comparison was made between the two groups for differences in anthropomorphic measurements and serum markers. Results: Three hundred and five individuals underwent oral glucose tolerance test of whom 40 had IGT. Complete baseline and 1-year data was available for 31 patients. After 1 year, patients in the orlistat group demonstrated a greater but insignificant decrease in weight (4.5 +/- 0.1 kg), and a significant increase in adiponectin (6.73 +/- 3.2 mu g/ml) and decrease in LPS (4.55 +/- 1.98 EU/ml) compared with- the diet-alone group. In the orlistat group the reduction in LPS was correlated with the increase in adiponectin (p < 0.005). Conclusion: The increase in adiponectin levels in the orlistat group would suggest that orlistat may reduce the progression to type 2 diabetes in South Asian individuals by raising serum adiponectin. The finding that LPS levels are also reduced by orlistat and that this reduction correlates with the increase in adiponectin raises the possibility that the increase in adiponectin may be mediated via an effect on LPS levels.