The dipeptidyl peptidase-4 inhibitor linagliptin attenuates inflammation and accelerates epithelialization in wounds of diabetic ob/ob mice

J Pharmacol Exp Ther. 2012 Jul;342(1):71-80. doi: 10.1124/jpet.111.191098. Epub 2012 Apr 4.

Abstract

In recent years, new and effective therapeutic agents for blood glucose control have been added to standard diabetes therapies: dipeptidyl peptidase-4 (DPP-4) inhibitors, which prolong the bioavailability of the endogenously secreted incretin hormone glucagon-like peptide-1 (GLP-1). Full-thickness excisional wounding was performed in wild-type (C57BL/6J) and diabetic [C57BL/6J-obese/obese (ob/ob)] mice. DPP-4 activity was inhibited by oral administration of linagliptin during healing. Wound tissue was analyzed by using histological, molecular, and biochemical techniques. In healthy mice, DPP-4 was constitutively expressed in the keratinocytes of nonwounded skin. After skin injury, DPP-4 expression declined and was lowest during the most active phase of tissue reassembly. In contrast, in ob/ob mice, we observed increasing levels of DPP-4 at late time points, when delayed tissue repair still occurs. Oral administration of the DPP-4 inhibitor linagliptin strongly reduced DPP-4 activity, stabilized active GLP-1 in chronic wounds, and improved healing in ob/ob mice. At day 10 postwounding, linagliptin-treated ob/ob mice showed largely epithelialized wounds characterized by the absence of neutrophils. In addition, DPP-4 inhibition reduced the expression of the proinflammatory markers cyclooxygenase-2 and macrophage inflammatory protein-2, but enhanced the formation of myofibroblasts in healing wounds from ob/ob mice. Our data suggest a potentially beneficial role of DPP-4 inhibition in diabetes-affected wound healing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Chemokine CXCL2 / genetics
  • Chemokine CXCL2 / metabolism
  • Cyclooxygenase 2 / genetics
  • Cyclooxygenase 2 / metabolism
  • Diabetes Mellitus, Experimental / drug therapy
  • Diabetes Mellitus, Experimental / genetics
  • Diabetes Mellitus, Experimental / metabolism
  • Diabetes Mellitus, Experimental / pathology
  • Dipeptidyl Peptidase 4 / genetics
  • Dipeptidyl Peptidase 4 / metabolism*
  • Dipeptidyl-Peptidase IV Inhibitors / pharmacology*
  • Epithelial Cells / metabolism
  • Epithelial Cells / pathology
  • Female
  • Glucagon-Like Peptide 1 / genetics
  • Glucagon-Like Peptide 1 / metabolism
  • Inflammation / drug therapy*
  • Inflammation / genetics
  • Inflammation / metabolism
  • Inflammation / pathology
  • Keratinocytes / drug effects
  • Keratinocytes / metabolism
  • Linagliptin
  • Macrophage Inflammatory Proteins / genetics
  • Macrophage Inflammatory Proteins / metabolism
  • Macrophages / drug effects
  • Macrophages / metabolism
  • Mice
  • Mice, Inbred C57BL
  • Mice, Obese
  • Myofibroblasts / drug effects
  • Myofibroblasts / metabolism
  • Neutrophils / drug effects
  • Neutrophils / metabolism
  • Purines / pharmacology*
  • Quinazolines / pharmacology*
  • Wound Healing / drug effects*
  • Wound Healing / genetics

Substances

  • Chemokine CXCL2
  • Cxcl2 protein, mouse
  • Dipeptidyl-Peptidase IV Inhibitors
  • Macrophage Inflammatory Proteins
  • Purines
  • Quinazolines
  • Linagliptin
  • Glucagon-Like Peptide 1
  • Ptgs2 protein, mouse
  • Cyclooxygenase 2
  • Dipeptidyl Peptidase 4
  • Dpp4 protein, mouse