Alcoholic steatohepatitis (ASH) is a complex multifactorial disease that can lead to
liver fibrosis and
cirrhosis if not treated promptly. Alcohol-induced oxidative stress and
inflammation are the main factors that cause
steatohepatitis and liver injury; however, probiotic bacteria in the gastrointestinal tract have been revealed to regulate immune responses and reduce oxidative stress, suggesting that functional probiotics could help to prevent ASH and liver injury. Despite numerous reports on the interactions between ASH and probiotics, the mechanisms underlying probiotic-mediated liver protection remain unknown. Therefore, the aim of the present study was to screen probiotics with high
antioxidant capacity and investigate the ability of different probiotic combinations to reduce
alcoholic liver disease (ALD) in a mouse model. It was identified that Lactobacillus plantarum (TSP05), Lactobacillus fermentum (TSF331) and Lactobacillus reuteri (TSR332) neutralized
free radicals and displayed high
antioxidant activity in vitro. In addition, these three functional probiotic strains protected mice from alcohol-induced liver injury in vivo. Mice treated with the probiotics demonstrated significantly lower
alanine aminotransferase,
aspartate aminotransferase and
triglyceride levels, which were associated with the downregulation of the proinflammatory
cytokines TNF-α and
IL-6. Furthermore, probiotic treatment upregulated
glutathione and
glutathione peroxidase activity, which are
bioindicators of oxidative stress in the liver. Collectively, the present results indicated that Lactobacillus strains TSP05, TSF331 and TSR332 reduced oxidative stress and inflammatory responses, thus preventing ASH development and liver injury.