Effects of probiotics on nonalcoholic fatty liver disease: a systematic review and meta-analysis

Abstract

Background: Nonalcoholic fatty liver disease (NAFLD) has become prevalent in recent decades, especially in developed countries, and approaches for the prevention and treatment of NAFLD are not clear. The aim of this research was to analyze and summarize randomized controlled trials that investigated the effects of probiotics on NAFLD. Methods: Seven databases (PubMed, Embase, the Web of Science, the Cochrane Library, China National Knowledge Infrastructure, Wan Fang Data, and VIP Database) were searched. Then, eligible studies were identified. Finally, proper data extraction, synthesis and analysis were performed by trained researchers. Results: Anthropometric parameters: with use of probiotics weight was reduced by 2.31 kg, and body mass index (BMI) was reduced by 1.08 kg/m2. Liver function: probiotic treatment reduced the alanine aminotransferase level by 7.22 U/l, the aspartate aminotransferase level by 7.22 U/l, the alkaline phosphatase level by 25.87 U/l, and the glutamyl transpeptidase level by −5.76 U/l. Lipid profiles: total cholesterol, low-density lipoprotein cholesterol, and triglycerides were significantly decreased after probiotic treatment. Their overall effects (shown as standard mean difference) were −0.73, −0.54, and −0.36, respectively. Plasma glucose: probiotics reduced the plasma glucose level by 4.45 mg/dl and the insulin level by 0.63. Cytokines: probiotic treatment decreased tumor necrosis factor alpha by 0.62 and leptin by 1.14. Degree of liver fat infiltration (DFI): the related risk of probiotics for restoring DFI was 2.47 (95% confidence interval, 1.61–3.81, p < 0.001). Conclusion: Probiotic treatment or supplementation is a promising therapeutic method for NAFLD.

Probiotics as a Complementary Therapy for Management of Obesity: A Systematic Review

“…Results varied from a no significant change to a significant decrease during 2–26 weeks' interventions. Regarding the observed improvement of anthropometric indices, from 20 meta-analyses included in the current study, 10 studies disclosed significant change in BW [ 2 , 3 , 5 , 8 , 11 , 12 , 16 , 17 , 19 , 20 ], 14 studies showed significant change in BMI [ 1 – 3 , 5 , 8 , 11 , 12 , 16 – 22 ], 6 studies reported change in WC [ 1 , 2 , 5 , 13 , 17 , 22 ], and 4 studies disclosed change in BFM [ 2 , 5 , 8 , 17 ]. In the study by Koutinkova et al, an improvement in anthropometric indices was reported when ≥3 species were used [ 5 ].…”

“…Six studies out of 20 total included studies were accomplished on both genders of obese adult patients with nonalcoholic fatty liver disease using diverse probiotic products as intervention constituted by various species like Streptococcus cerevisiae , Streptococcus thermophilus , and Lactobacillus spp. [ 14 , 15 , 18 , 19 , 21 , 25 ]. Three of these studies showed no significant change in anthropometric indices [ 14 , 15 , 25 ], contrasting to others [ 18 , 19 , 21 ].…”

“…[ 14 , 15 , 18 , 19 , 21 , 25 ]. Three of these studies showed no significant change in anthropometric indices [ 14 , 15 , 25 ], contrasting to others [ 18 , 19 , 21 ]. Among the studies displaying beneficial effects on BMI, two of them showed better results when Bifidobacterium and Lactobacillus species were administered (−1.46 kg/m 2 (95% CI: −2.44, −0.48) and −1.08 kg/m 2 (95% CI: −2.05, −0.11)) [ 18 , 19 ].…”

Overview of Non-Alcoholic Fatty Liver Disease (NAFLD) and the Role of Sugary Food Consumption and Other Dietary Components in Its Development

“…Consequently, modulating GM to reverse dysbiosis could be a potential therapeutic approach for treating NAFLD. Supplementation with probiotics, prebiotics, or synbiotics has been proven to treat dysbiosis and improve NAFLD [ 49 ]. Studies performed in animals suggested that probiotics could improve hepatic steatosis, fibrosis, and some metabolic markers [ 50 , 51 ].…”

Probiotics as a Treatment for “Metabolic Depression”? A Rationale for Future Studies

“…Meanwhile, clinical research on probiotics conducted so far has found positive results in NAFLD subjects. Probiotics in recent systematic reviews and meta-analyses were shown to be superior to placebo regarding several anthropometric and laboratory metabolic parameters, including serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in both adult and paediatric patients [ 93 , 95 , 112 ], as well as inflammation markers [ 112 , 113 ] in NAFLD patients.…”