NCT03178019

DPP4 Activity, Microvascular Reactivity and Inflammation

Dipeptidyl Peptidase 4 (DPP4) Activity and Its Associations With Endothelial Dysfunction, Inflammatory and Metabolic Markers, Heart Rate and Blood Pressure Variability, and Measures of Adiposity in Subjects With Different Grades of Glucose Tolerance

• Status: Completed
• Phase: —
• Study type: Observational
• Enrollment: 52 (actual)
• Sponsor: Rio de Janeiro State University · Academic / Other
• Sex: All
• Age: 18 Years – 50 Years
• Healthy volunteers: Accepted

Summary

Dipeptidyl peptidase 4 (DPP4) is a serine exopeptidase able to inactivate various oligopeptides involved in inflammation, immunity and vascular function. Our aim was to investigate the associations between constitutive levels of DPP4 activity and inflammatory biomarkers, skin microvascular reactivity, gut peptides, insulin resistance indexes, heart rate and blood pressure variability, and measures of adiposity in subjects with different grades of glucose tolerance.

Detailed description

Dipeptidyl peptidase 4 (DPP4), also known as adenosine deaminase binding protein or cluster of differentiation 26 (CD26), is a serine exopeptidase able to inactivate various oligopeptides composed of proline, hydroxyproline, or alanine as the penultimate residue. In recent years, DPP4 has received attention due to its ability to rapidly inactivate the main incretins secreted by the gastrointestinal tract: glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). As its own name already says, incretins enhance insulin secretion in a glucose-dependent fashion, but also suppress or modulate glucagon secretion. Since it was demonstrated that type 2 diabetes mellitus (T2D) have incretin deficiency and hyperglucagonemia on its physiopathology, gliptins emerged as a new class of drugs for the treatment of this disease, acting through the inhibition of DPP4 and consequently ameliorating these defects. DPP4 not only inactivate incretins but also a number of cytokines, chemokines, and neuropeptides involved in inflammation, immunity and vascular function. Furthermore, evidence from in vitro and in vivo studies, including clinical ones in T2D, suggested that gliptins' inhibition of DPP4 was associated with reduction of inflammatory biomarkers and also attenuation of endothelial dysfunction and atherogenesis, possibly through regulation of the DPP4 substrates. There is a paucity of studies that associate the constitutive levels of DPP4 activity (i.e., outside the context of pharmacological inhibition of the enzyme) with markers of inflammation and endothelial function, specially tested on skin microcirculation. We hypothesized that constitutive levels of DPP4 activity might be directly associated to inflammation and inversely correlated with skin blood flux and one or more components of vasomotion (suggesting an association with endothelial disfunction) even in the absence of diabetes. Our aim was to investigate the associations between constitutive levels of DPP4 activity and inflammatory biomarkers, skin microvascular reactivity, gut peptides, insulin resistance indexes, heart rate and blood pressure variability, and measures of adiposity in subjects with different grades of glucose tolerance.

Conditions

• Overweight
• Pre Diabetes
• Diabetes Mellitus Type 2 Without Complication

Interventions

Type	Name	Description
OTHER	Laser-Doppler methods	This was a cross-sectional study in which participants were subjected to a screening phase before being eligible to participate in the study. All subjects were submitted to Laser-Doppler methods (assessment of microcirculatory blood flow), bioimpedance analysis (assessment of body composition), venous blood collections (laboratory analysis), and Finometer Pro (assessment of heart rate variability and blood pressure variability).

Timeline

• Start date: 2014-02-01
• Primary completion: 2015-12-01
• Completion: 2016-12-01
• First posted: 2017-06-06
• Last updated: 2017-06-08