Lactobacillus attenuates progression of nonalcoholic fatty liver disease by lowering cholesterol and steatosis

Background/Aims: Nonalcoholic fatty liver disease (NAFLD) is closely related to gut-microbiome. There is a paucity of research on which strains of gut microbiota affect the progression of NAFLD. This study explored the NAFLD-associated microbiome in humans and the role of Lactobacillus in the progression of NAFLD in mice. Methods: The gut microbiome was analyzed via next-generation sequencing in healthy people (n=37) and NAFLD patients with elevated liver enzymes (n=57). Six-week-old male C57BL/6J mice were separated into six groups (n=10 per group; normal, Western, and four Western diet + strains [10(9) colony-forming units/g for 8 weeks; L. acidophilus, L. fermentum, L. paracasei, and L. plantarum]). Liver/body weight ratio, liver pathology, serum analysis, and metagenomics in the mice were examined. Results: Compared to healthy subjects (1.6 +/- 4.3), NAFLD patients showed an elevated Firmicutes/Bacteroidetes ratio (25.0 +/- 29.0) and a reduced composition of Akkermansia and L. murinus (P<0.05). In the animal experiment, L. acidophilus group was associated with a significant reduction in liver/body weight ratio (5.5 +/- 0.4) compared to the Western group (6.2 +/- 0.6) (P<0.05). L. acidophilus (41.0 +/- 8.6), L. fermentum (44.3 +/- 12.6), and L. plantarum (39.0 +/- 7.6) groups showed decreased cholesterol levels compared to the Western group (85.7 +/- 8.6) (P<0.05). In comparison of steatosis, L. acidophilus (1.9 +/- 0.6), L. plantarum (2.4 +/- 0.7), and L. paracasei (2.0 +/- 0.9) groups showed significant improvement of steatosis compared to the Western group (2.6 +/- 0.5) (P<0.05). Conclusions: Ingestion of Lactobacillus, such as L. acidophilus, L. fermentum, and L. plantarum, ameliorates the progression of nonalcoholic steatosis by lowering cholesterol. The use of Lactobacillus can be considered as a useful strategy for the treatment of NAFLD.

Automated summary

The study found that NAFLD patients have abnormal composition of gut microbiota, and intake of Lactobacillus (such as L. acidophilus) can lower cholesterol levels and improve the progression of NAFLD.