Disturbances in angiogenesis and vascular maturation in the skin are associated with diabetic kidney disease in type 1 diabetes

Abstract

Introduction. The skin, as one of the most accessible tissues, is frequently used for investigations of microcirculation and angiogenesis. The aim of this study was to assess the relationship between the dermal microvessel density (MVD) and maturity and the presence of diabetic kidney disease (DKD) in adults with type 1 diabetes (T1D). Skin as the most accessible organ served as a model for the study of angiogenesis. Materials and methods. 148 consecutive T1D patients (87 men), median age of 41 [interquartile range (IQR): 31–49] years and diabetes duration of 21 (17–30) years, participated in the study. The patients were under the care of the Department of Internal Medicine and Diabetology, Poznan University of Medical Sciences. Diabetic kidney disease was diagnosed in patients with increased albuminuria and at least 10-year duration of diabetes or evidence of diabetic retinopathy. The skin biopsy was performed on distal part of lower leg, using a sterile, disposable 3 mm biopsy punch with plunger (Disposable Biopsy Punches, Integra™ Miltex ® ). In the immunohistochemical analyses, we used: anti-CD133, anti-CD34, anti-CD31, and anti-von Willebrand factor (vWF) autoantibodies. Microvessel density measurement in all specimens was performed using “hot spots technique”. Slides were scanned using the MiraxMidi scanner (Carl Zeiss) and were viewed using CaseViewer (3DHISTECH Ltd. Budapest, Hungary). Data were analyzed using Statistica v. 13 software. Results. In the study group 21 patients with diagnosis DKD+, as compared to 127 subjects withaout DKD–, had longer duration of diabetes [30 (IQR: 21–36) vs. 21 (16–28) years, p = 0.002], higher prevalence of hypertension [14 (67%) vs. 37 (29%), p = 0.002], lower estimated glomerular filtration rate (eGFR) [66 (55–88) vs. 94 (83–106) mL/min/1.73 m 2 , p < 0.001]. Median MVD compared between groups with and without DKD, was similar for CD34+ vessels/1 mm 2 [123 (100–170) vs. 121 (100–170), p = 0.775], CD133+ vessels/1 mm2 [79 (50–100) vs. 79 (63–93), p = 0.823], and for CD31+ vessels/ 1 mm 2 [29 (21–46) vs. 38 (17–58), p = 0.454]. Median MVD vWF+ vessels/1 mm 2 was lower in the group with than without DKD: 42 (25–54) vs. 54 (43–71), p = 0.009. The values given above were calculated for both layers of the dermis (papillary and reticular dermis). In multivariate logistic regression analysis presence of diabetic kidney disease was associated with lower median vWF+ MVD [odds ratio: 0.97 (95% confidence interval: 0.95–0.99), p = 0.017], with adjustment for age, gender, eGFR value, diabetes duration and presence of hypertension. MVD did not differ significantly between chronic kidney disease stages. Conclusion. In patients with type 1 diabetes and diabetic kidney disease the disturbances in the angiogenesis and vascular maturation are present. The number of mature blood vessels (vWF+) in the skin is reduced. Disturbances in the angiogenesis occur at early stages of diabetic kidney disease.