PATIENTS AND METHODS: Fasting plasma PP concentrations were measured in 104 overweight and obese subjects (46 men and 58 women). In the same subjects, total and regional adipose tissue, including total visceral adipose tissue (VAT) and total subcutaneous adipose tissue (TSAT), were measured using whole-body magnetic resonance imaging. Intrahepatocellular lipid content (IHCL) was quantified by proton magnetic resonance spectroscopy.
RESULTS: Fasting plasma PP concentrations positively and significantly correlated with both VAT (r = 0.57, P < .001) and IHCL (r = 0.51, P < .001), but not with TSAT (r = 0.02, P = .88). Fasting PP concentrations independently predicted VAT after controlling for age and sex. Fasting PP concentrations independently predicted IHCL after controlling for age, sex, body mass index (BMI), waist-to-hip ratio, homeostatic model assessment 2-insulin resistance, (HOMA2-IR) and serum concentrations of triglyceride (TG), total cholesterol (TC), and alanine aminotransferase (ALT). Fasting PP concentrations were associated with serum ALT, TG, TC, low- and high-density lipoprotein cholesterol, and blood pressure (P < .05). These associations were mediated by IHCL and/or VAT. Fasting PP and HOMA2-IR were independently significantly associated with hepatic steatosis (P < .01).
CONCLUSIONS: Pancreatic polypeptide is a novel predictor of visceral and liver fat content, and thus a potential biomarker for cardiovascular risk stratification and targeted treatment of patients with ectopic fat deposition.
METHODS: Seventy-six obese subjects were randomly placed into two groups. The first group received three daily 120 mg dosages of orlistat for nine months (n=39), and the second group received a once daily 10 or 15 mg dosage of sibutramine for nine months (n=37). Baseline measurements for weight, body mass index (BMI), waist circumference (WC), body fat percentage (BF), visceral fat (VF), adiponectin, fasting plasma glucose (FPG), fasting insulin, pancreatic B cell secretory capacity (HOMA%B), insulin sensitivity (HOMA%S), insulin resistance (HOMA-IR) and serum high sensitivity C-reactive protein (hs-CRP) were performed and repeated during the sixth and ninth months of treatment.
RESULTS: Twenty-four subjects completed the trial in both groups. For both groups, weight, BMI, WC, BF, VF, HOMA-IR and hs-CRP were significantly lower at the end of the nine month intervention. However, there were no significant differences between the two groups for these parameters with nine months treatment. There was a significant decrease in FPG in orlistat group; while fasting insulin and HOMA%B reduced in sibutramine group. For both groups, there were also significant increases in adiponectin levels and HOMA%S at the end of the nine month intervention.
CONCLUSION: Nine months of treatment with orlistat and sibutramine not only reduced weight but also significantly improved BMI, WC, BF, VF, FPG, adiponectin, fasting insulin, HOMA%B, HOMA%S, HOMA-IR and hs-CRP. These improvements could prove useful in the reduction of metabolic and cardiovascular risks in obese subjects.