Kostov Krasimir, Blazhev Alexander
Department of Pathophysiology, Medical University-Pleven, 1 Kliment Ohridski Str., 5800 Pleven, Bulgaria.
Department of Biology, Medical University-Pleven, 1 Kliment Ohridski Str., 5800 Pleven, Bulgaria.
Diagnostics (Basel). 2021 May 19;11(5):900. doi: 10.3390/diagnostics11050900.
Thickening of the vascular basement membrane (BM) is a fundamental structural change in the small blood vessels in diabetes. Collagen type IV (CIV) is a major component of the BMs, and monitoring the turnover of this protein in type 2 diabetes (T2D) can provide important information about the mechanisms of vascular damage. The aim of the study was through the use of non-invasive biomarkers of CIV (autoantibodies, derivative peptides, and immune complexes) to investigate vascular turnover of CIV in patients with long-term complications of T2D. We measured serum levels of these biomarkers in 59 T2D patients with micro- and/or macrovascular complications and 20 healthy controls using an ELISA. Matrix metalloproteinases-2 and -9 (MMP-2 and MMP-9) were also tested. In the T2D group, significantly lower levels of CIV markers and significantly higher levels of MMP-2 and MMP-9 were found compared to controls. A significant positive correlation was found between IgM antibody levels against CIV and MMP-2. These findings suggest that vascular metabolism of CIV is decreased in T2D with long-term complications and show that a positive linear relationship exists between MMP-2 levels and CIV turnover in the vascular wall.
血管基底膜（BM）增厚是糖尿病患者小血管的一种基本结构变化。IV型胶原（CIV）是基底膜的主要成分，监测2型糖尿病（T2D）中该蛋白的周转情况可为血管损伤机制提供重要信息。本研究的目的是通过使用CIV的非侵入性生物标志物（自身抗体、衍生肽和免疫复合物）来研究T2D长期并发症患者中CIV的血管周转情况。我们使用酶联免疫吸附测定法（ELISA）测量了59例患有微血管和/或大血管并发症的T2D患者以及20名健康对照者血清中这些生物标志物的水平。还检测了基质金属蛋白酶-2和-9（MMP-2和MMP-9）。与对照组相比，T2D组中CIV标志物水平显著降低，MMP-2和MMP-9水平显著升高。发现抗CIV的IgM抗体水平与MMP-2之间存在显著正相关。这些发现表明，伴有长期并发症的T2D患者中CIV的血管代谢降低，并且表明MMP-2水平与血管壁中CIV周转之间存在正线性关系。
