Protective Effects of Selected Herbal Additives Against Ochratoxin A-Induced Toxicosis and Oxidative Damage in Rabbits

The protective effects of herbal feed additives Withania somnifera, Silybum marianum, Centella asiatica, and silymarin (administered at feed levels of 4000 ppm, 5000 ppm, 4600 ppm, and 25,000 ppm, respectively) against the toxic effects of ochratoxin A (OTA) (administered at 2 ppm) were investigated in 48 New Zealand White rabbits (37 days old) over an 80-day experimental period. A decrease in body weight was seen in rabbits exposed to OTA alone, but that decrease was less pronounced in rabbits receiving herbal supplements. The most severe lesions in OTA-treated rabbits were found in the liver, kidneys and spleen, while milder lesions were seen in the heart, intestine and lungs. The intensity of macroscopic, histopathological and biochemical changes was highest in rabbits exposed to OTA alone, followed by rabbits additionally supplemented with herbal additives, as evidenced by histopathological findings and serum levels of blood urea nitrogen (BUN), creatinine, aspartate aminotransferase (AST), and alanine aminotransferase (ALT). The most pronounced protective effects of the herbal additives were observed in the kidneys and liver. Oxidative stress was significantly increased in rabbits exposed to OTA alone, as evidenced by elevated reactive oxygen species (ROS), nitric oxide (●NO), ascorbyl radicals (●Asc), protein oxidation (PO), procollagen type I alpha 1 (COL1A1), malondialdehyde (MDA), kidney injury molecule-1 (KIM-1), hydroxyproline (Hyp), advanced glycation end products (AEGs), heme oxygenase-1 (HO-1), catalase (CAT), and 8-hydroxy-2′-deoxyguanosine (8-OHdG), as well decreased superoxide dismutase (SOD) and glutathione peroxidase-1 (GPx-1) activities, while protective effects were seen for all herbal additives, and better expressed for Centella asiatica and Silybum marianum.