Comparative evaluation of bio-protective effects of alive and dead (heat- inactivated) Lactiplantibacillus plantarum strains against Cadmium - induced toxicity in wistar rats

This study was conducted to evaluate the bio - protective potential of alive and dead (heat - inactivated) Lactiplantibacillus plantarum strains against cadmium toxicity in Wistar rats. The aim was to determine whether alive and heat - inactivated Lactiplantibacillus plantarum strains could alleviate cadmium - induced inflammatory and oxidative stress responses and reduce serum cadmium levels in rats. The study included forty-eight male albino Wistar rats, which were distributed equally among six groups: control (n = 8), cadmium (n = 8), alive Lactiplantibacillus plantarum (n = 8), dead Lactiplantibacillus plantarum (n = 8), cadmium + alive Lactiplantibacillus plantarum, and cadmium + dead Lactiplantibacillus plantarum. Rats in the cadmium, cadmium + alive Lactiplantibacillus plantarum, and cadmium + dead Lactiplantibacillus plantarum groups received cadmium chloride (2 mg/ kg) orally by gastric gavage three times a week for 4 weeks. Alive and dead Lactiplantibacillus plantarum (109 – 1010 cfu / mL) suspensions were administered to alive Lactiplantibacillus plantarum, dead Lactiplantibacillus plantarum, cadmium + alive Lactiplantibacillus plantarum, and cadmium + dead Lactiplantibacillus plantarum groups with the same frequency and duration. The control group received physiological saline. After experimental completion, decapitation was performed, and serum samples were collected for cadmium concentrations, cytokines (TNF - α, IL - 6, IL - 10, IL - 1β), and antioxidant (Malondialdehyde, superoxide dismutase, glutathione peroxidase, catalase) levels. cadmium administration caused a significant increase in serum TNF - α and IL - 6 levels but decreased IL - 1β levels (P < 0.05). Superoxide dismutase and glutathione peroxidase levels were reduced, but Malondialdehyde concentrations elevated in only the cadmium - exposed group (P < 0.05). Lactiplantibacillus plantarum administrations alleviated the inflammatory response by providing a significant decrease in IL - 6 levels, especially in the heat - inactivated form (cadmium + dead Lactiplantibacillus plantarum) (P < 0.05). Both alive and dead forms showed partial recovery trends in superoxide dismutase, glutathione peroxidase, and catalase. Lactiplantibacillus plantarum exhibited partially anti-inflammatory, antioxidant, and metal-binding properties against cadmium toxicity in both forms and presented a usable bioprotective model in terms of food safety and veterinary toxicology when applied with a milk matrix.