LP-cs Ameliorated CCl 4 -Induced Acute Liver Injury by Suppression of Cellular Stress

Abstract Background: Acute liver injury (ALI) involves excessive oxidative stress(OS) and inflammatory responses, leading to a high mortality rate due to lack of effective therapy. Carbon tetrachloride (CCl4) is widely used to induce ALI by induction of reactive oxygen species. Probiotics, including Lactobacillus plantarum ST-III, have been shown to produce antibacterial and antioxidant substances such as organic acids or bacteriocins that reduce liver damage. Nevertheless, the effect of Lactobacillus plantarum ST-III culture supernatant (L-P-cs) on CCl4-induced liver injury remains unclear.Methods: Mice were pretreated with L-P-cs or medium for 14days before one dose of 0.2% CCl4 at 10ml/kg body weight delivered by intraperitoneal injection. CCl4-induced liver injury was examined by measuring serum levels of liver transaminases and high mobility-group box 1 protein (HMGB1) and liver histological staining. Inflammation and apoptosis in liver were evaluated by real-time PCR, enzyme-linked immunosorbent assay (ELISA), and TUNEL staining. Apoptosis in NCTC 1469 cells was detected using CCK8 and western blotting (WB). In liver, OS and endoplasmic reticulum stress(ERS)-related proteins were measured using kits and WB.Results: L-P-cs significantly ameliorated CCl4-induced liver injury and reduced CCl4- induced inflammatory response and apoptosis, consistent with NCTC 1469 cells' results. L-P-cs also restored CCl4-induced increases in cell OS and ERS to normalize liver function. Specifically, L-P-cs pretreatment decreased CCl4-induced increases in nuclear factor (erythroid-2 related) factor 2, HO-1, superoxide dismutase, glucose regulatory protein, and activating transcription factor 6.Conclusion: L-P-cs synergistically improves liver lobule necrosis, hepatocyte inflammation, and apoptosis by reducing liver OS and ERS.