Influence of Diet and Gender on Plasma DPP4 Activity and GLP-1 in Patients with Metabolic Syndrome: An Experimental Pilot Study.

Glucagon-Like Peptide-1 (GLP-1) is hydrolyzed by Dipeptidyl-Peptidase 4 (DPP4), and several studies suggest that both GLP-1 and DPP4 inhibitors have potentially beneficial effects on cardiovascular risks. The objective of this study was to analyze the differences between plasma GLP-1 and DPP4 activity in male and female patients with metabolic syndrome, and its relationship with physiological and metabolic parameters. The study included 25 apparently healthy Controls (C) and 21 Metabolic Syndrome patients (MS). Anthropometric indices, cardiovascular risk-score, and Mediterranean Diet Adherence (AMeDit) were evaluated. Fasting glucose, glycosylated hemoglobin (HbA1c), and insulin were measured. Insulin, GLP-1, and plasma DPP4 were determined within the first 30-min postprandial period. Body-Mass-Index was significantly higher, and AMeDit was significantly lower, but only in MS women. However, fasting glucose, HbA1c, and postprandial insulin were significantly higher in MS men, but not in MS women. Postprandial GLP-1 levels were lower in C men than in C women. Interestingly, in comparison with controls, we found significant lower levels of plasma DPP4 in MS-women only. Moreover, negative lineal regressions were established between DPP4 activity with waist-to-hip ratio and cardiovascular risk-score, and positive lineal regression with AMeDit. These results indicate gender differences in the behavior of GLP-1 and DPP4 activity in MS, which could be relevant for its treatment with GLP-1 analogues and DPP4 inhibitors.