Avramenko Y. «Pathomorphological characteristics of cerebral microvessels in patients with diabetes mellitus type II complicated by ischemic cerebral infarction»

Pathomorphological and immunohistochemical parameters of microvessels of the pial membrane and cerebral cortex in patients with type 2 diabetes mellitus, in patients with cerebral atherosclerosis with hypertension and in patients with ischemic cerebral hemispheric infarction in the stage of necrosis with necrosis on the background of diabetes mellitus and on the background of cerebral atherosclerosis with hypertension. The results of histopathological, morphometric, immunohistochemical studies showed that in type 2 diabetes mellitus in the arterioles of the pial membrane of the brain were determined focal thickening of the basement membrane, uneven thickening of the inner elastic membrane with the accumulation of PAS-positive material, loss of middle muscle smooth muscle cells, as well as uneven thickening of the vascular wall due to plasma infiltration or focal hyalinosis. The arterioles of the pial membrane of the brain had significantly larger outer and inner diameters, as well as 84.53 % thickened vascular wall, which was associated with an increase of 23.02 % in the area of expression of type 4 collagen in the meninges. Significantly higher indicators of functional indices of Wagenworth and Kernogan were registered. In type 2 diabetes mellitus, there were signs of intense brain arteriole reendothelisation in response to endothelial cell damage and apoptosis, significantly higher mean level of Ki-67 and caspase-3 expression in microvascular cells of the pial membrane. 8 Cortical arterioles in deceased patients with type 2 diabetes mellitus had thickened basement membranes and thickened inner elastic membranes, as well as an unevenly thickened wall due to focal or total infiltration of PAS -positive glycoproteins of blood plasma or due to its hyalinosis with loss of smooth muscle cells. Morphometric measurement showed a significant thickening of the walls of the arterioles, which were significantly thicker by 40.65 % than in the conditional control group, and by 5.95 %, compared with the group of patients with dyscirculatory ischemic encephalopathy. Apoptosis of single endothelial cells and pericytes and significant accumulation of collagen fibers in the expanded basement membranes were observed in the arterioles by electron microscopy. There was a significant increase in the expression area of type 4 collagen in the microvessels of the cerebral cortex - by 22.96 % compared with the conditional control group, which had no significant difference from the increased similar rate of patients with dyscirculatory ischemic encephalopathy. The outer diameter of the arterioles was significantly larger than in the conditional control group and in patients with dyscirculatory ischemic encephalopathy. The cerebral cortex arterioles in both comparison groups had significantly increased Wagenworth and Kernogan indices.