No abstract

Diabetes mellitus (DM) has emerged as a public healthcare problem. Sustained hyperglycemia has been linked with many complications including impaired male fertility. The aim of the study: to evaluate the effect of STZ-induced diabetes mellitus on testicular immunomorphology both in the peripubertal period and adulthood of rats. Material and methods. Peripubertal male rats were injected with STZ (70 mg/kg), adult rats received 60 mg/kg. Immunohistochemical staining was performed to assess cell proliferation (Ki-67), apoptosis (caspase-3), expression of androgen receptors (AR), Wilms Tumor (WT1) protein. Also, the morphology of blood vessels was analyzed on the basis of CD34-immunoreactivity. Taking into consideration the small groups of animals, statistical analysis was made with the Mann–Whitney U test. Results. Fewer rows of proliferating spermatogonia were observed in the experimental animals (P < 0.05) of both age groups. Surprisingly, diabetes resulted in decreased caspase-3 expression (P < 0.05) except for the early period (2 weeks) in the peripubertal group, in which this trend was not observed. The same principles are true in terms of AR expression in seminiferous tubules. Hyperglycemia prevented immature testes from the complete development but thickens the walls of microvessels (P < 0.05). Also, the atrophy of spermatogenic epithelium and Sertoli cells was registered in most tubules of all the experimental groups (P < 0.05). Conclusion. the diabetic injury of testicular tissue is a long time process possessing characteristic feature in the peripubertal period, for example, the later development of AR deficiency. In addition, the high level of apoptosis is characteristic of an immature testis and so is the tendency of caspase-immunoreactivity to persist.

Medico-social problem of diabetes is caused by early disability and mortality of patients due to specific complications of micro- and macroangiopathies. Therefore, the aim of our study was to establish morphological changes in vessels of the hemomicrocirculatory flow of the testes of immature rats with experimental streptozotocin diabetes mellitus (SDM). The material for the study were the testicles of 20 two-month-old immature (weighing 65-95 g) white outbred male rats, which were divided equally into 2 groups: experimental and control ones. SDM in animals of the experimental group was simulated by a single intraperitoneal injection of streptozotocin (dissolved in 0.1 M citrate buffer solution with a pH of 4.5) at a dose of 7 mg per 100 g of mass. The control group of animals received intraperitoneally an equivalent dose of 0.1 M citrate buffer. Histological, electron microscopic, biochemical, morphometric and statistical research methods were used. It was found that in the early stages of SDM (14th day) on the background of hyperglycemia in the hemomicrocirculatory flow of the testes there is a spasm of the vessels of the afferent link, which is confirmed by a decrease in the area of arterioles lumen and an increase in their VI. On the 56th day of SDM, on the background of elevated levels of glucose and glycosylated hemoglobin in the links of the hemorrhagic circulatory flow of the testes there are initial signs of diabetic microangiopathy, manifested by: hemorheological disorders in micro-hemo-vessels (erythrocyte sludges, adhesion of erythrocytes and platelets, microclasmatosis), decreased capacity of arterioles and capillaries (increase in VI, respectively by 1.2 and 1.9 times), microclasmatosis, thickening and proliferation of the basement membrane of capillaries. Thus, on the 56th day of SDM in the hemomicrocirculatory flow of the testes, the development of diabetic microangiopathy is observed, which leads to the disruption of the blood-testis barrier, and as a consequence, to a violation of spermatogenesis.