Protective effects of adenosine triphosphate, thiamin, thiamin pyrophosphate, and their combination against linezolid-induced renal injury and lactic acidosis in rats

Linezolid, an oxazolidinone antibiotic effective against Gram-positive pathogens, may cause nephrotoxicity and lactic acidosis during prolonged therapy. This experimental study investigated the protective effects of adenosine triphosphate (ATP), thiamin, thiamin pyrophosphate (TPP), and their combination (ATTP) on linezolid-induced renal injury and lactic acidosis in rats. Thirty-six male Wistar rats were randomly divided into six groups (<i>n</i> = 6): healthy control (HG), linezolid only (LZD), ATP+linezolid (ATLZD), thiamin + linezolid (TLZD), TPP+linezolid (TPLZD), and ATP+thiamin + TPP+linezolid (ATTPL). Linezolid (125 mg/kg, orally) was administered twice daily, while ATP (4 mg/kg), thiamin (20 mg/kg), and TPP (20 mg/kg) were given intraperitoneally once daily for 28 days. At the end of treatment, kidney tissues were examined for oxidative stress markers [malondialdehyde (MDA), total glutathione (tGSH), superoxide dismutase (SOD), catalase (CAT)] and histopathology, and blood samples were analyzed for blood urea nitrogen (BUN), creatinine, and lactate. Linezolid increased oxidative stress, suppressed antioxidants, and elevated BUN, creatinine, and lactate levels. ATP partially improved the oxidative balance in renal tissue but failed to prevent hyperlactatemia and impaired renal function. Thiamin did not produce significant changes. TPP markedly improved oxidative stress markers and reduced renal dysfunction. The triple combination provided the most pronounced protection, restoring antioxidant defenses, kidney function, and lactate levels to near-control values. Histopathological evaluation revealed marked tubular degeneration, interstitial hemorrhage, and mononuclear cell infiltration in the linezolid group, which were markedly improved by TPP and combination therapy. These findings indicate that TPP protects against linezolid-induced nephrotoxicity and lactic acidosis, with its efficacy further enhanced by ATP.