Telmisartan but Not Candesartan Affects Adiponectin Expression In Vivo and In Vitro

To examine the effects of telmisartan on peroxisome proliferator-activated receptor gamma activation, we compared the effects of telmisartan with those of candesartan on adipocytokines and glucose and lipid metabolism in vivo and in vitro. In vivo, 56 patients with both type 2 diabetes and hypertension were enrolled and randomized to receive either telmisartan (40 mg) or candesartan (8 mg) for 3 months. Serum adiponectin, HbA1c levels, lipid profiles and blood pressure were recorded at the beginning and 3 months later. In vitro, differentiated 3T3-L1 adipocytes were treated with telmisartan, candesartan, pioglitazone or vehicle for 24 h, and then adiponectin mRNA and protein levels were measured. The results showed that most of the metabolic parameters, including the lipid profiles, did not change significantly during the study in either group. However, the changes in serum adiponectin and plasma glucose over 3 months were significantly greater in the telmisartan group than in the candesartan group. In vitro, although the protein level of adiponectin was not significantly elevated, the mRNA expression of adiponectin was elevated 1.5-fold by telmisartan in 3T3-L1 adipocytes. Our findings suggest that telmisartan may have beneficial effects in type 2 diabetes beyond its antihypertensive effect.