Renal proliferation and apoptosis against ascorbic acid administration in a model of acute radiation nephropathy

Abstract

BACKGROUND: Radiation exposure, an integral part of the treatment of malignant neoplasms, carries a risk of radiation nephropathy due to the high radiosensitivity of the kidneys. The study of renal tissue proliferation and apoptosis is one of the keys to understanding the mechanisms of radiation damage and developing treatment strategies. AIM: Evaluation of intrarenal regulation, proliferation, and apoptosis during pre-radiation administration of ascorbic acid. METHODS: Wistar rats (n=90) were divided into groups: I - control (n=15); II - irradiation, 2 Gy dose (n=15); III - irradiation, 8 Gy dose (n=15); IV - irradiation, 2 Gy dose + ascorbic acid (intraperitoneal injection; dose 50 mg/kg) (n=15); V - irradiation, 8 Gy dose + ascorbic acid (intraperitoneal injection; dose 50 mg/kg) (n=15); VI - ascorbic acid (intraperitoneal injection; dose 50 mg/kg) (n=15). Kidney slides were stained with hematoxylin and eosin. In addition, immunohistochemical evaluation of the expression level of Ki-67- and Cas-3-positive cells was performed. RESULTS: The histological study showed that pre-radiation administration of ascorbic acid (intraperitoneal injection; dose 50 mg/kg) in the model of acute radiation nephropathy induced by local irradiation with electrons at doses 2 Gy and 8 Gy contributed to statistical reduction of pathomorphologic changes. According to the results of immunohistochemical evaluation of proliferation and apoptosis - distribution of Ki-67- and Cas-3-positive cells in the tubules, epitheliocytes of proximal and distal tubules of nephrons in mono-irradiation groups revealed activation of the terminal stage of cell death, which correlated with the dose of electron irradiation. At the same time, in the experimental groups with pre-irradiation administration of ascorbic acid a statistically significant decrease in the intensity of apoptosis was recorded. CONCLUSION: Pre-radiation administration of ascorbic acid statistically reduces the strength of radiation-induced kidney damage, as well as the effect of electron irradiation on the life cycle of tubular cells, epitheliocytes of nephron tubules, while increasing the effectiveness of antioxidant defense.