Renal toxicity of methylprednisolone in male Wistar rats and the potential protective effect by boldine supplementation

Objective Intravenous corticosteroids, methylprednisolone (MPL), which is one of the drugs that induce glomerular kidney diseases, when used for a long time at high dose by doctors to treat acute renal inflammation, promote the development of reactive oxygen species (ROS)-induced renal toxicity. This study investigated the role of boldine, a natural antioxidant with anti-apoptotic and anti-inflammatory properties, against MPL-induced renal toxicity in male Wistar rats. Methods 120 rats were divided into eight equal groups as follows: G1 (control), G2, 3, and 4 (rats orally administered 5, 10, and 50 mg boldine/kg/day; respectively, for 28 days), G5 (rats intramuscularly injected with 100 mg MPL/kg only on the last three days), G6, 7, and 8 (rats administered boldine + MPL). After the last MPL injection, rats were sacrificed at intervals of 1, 24, and 48 h. Results There was a significant increase in body weight, blood glucose, and urea levels, as well as a decrease in albumin level in serum. Oxidative stress markers levels increased at all times, and gene expression of anti-oxidant enzymes increased at 24 h. According to immunohistochemistry, there was a considerable increase in P53 and TNF-α levels following MPL therapy. The cell death DNA assays revealed detectable necrosis and apoptosis, induced by MPL treatment. Conclusions Oral administration of boldine has a modulatory protective, anti-oxidant, anti-apoptotic, and anti-inflammatory effect against free radicals.