Background: Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world. Oral administration of synbiotic has been proposed as an effective treatment of NAFLD because of its modulating effect on the gut flora, which can influ- ence the gut-liver axis.

Objective: The objective was to evaluate the effects of supplemen- tation with synbiotic on hepatic fibrosis, liver enzymes, and inflam- matory markers in patients with NAFLD.

Design: In a randomized, double-blind, placebo-controlled clinical trial conducted as a pilot study, 52 patients with NAFLD were supplemented twice daily for 28 wk with either a synbiotic or a pla- cebo capsule. Both groups were advised to follow an energy-balanced diet and physical activity recommendations.

RCT pilot study, n=52 (NAFLD)

Synbiotic bid vs Placebo bid for 28 weeks + energy balanced-diet and physical activity recommendations

Better liver parameters (ALT, AST, GGT, TNF-alfa, NF-kappa-B, fibrosis score)

This is the best-known study about synbiotic supplementation in NAFLD, which was published in American Journal of Clinical Nutrition in 2014. This study was conducted for 28 weeks, with 52 NAFLD subjects.

At the first visit (week 0), baseline data were gathered and patients were provided with a 7-wk supply of capsules. At each follow-up visit (every 7 wk), patients were given another set of capsules. Each synbiotic capsule (Protexin) contained 200 million of 7 strains of friendly bacteria (Lactobacillus casei, Lactobacillus rhamnosus, Streptococcus thermophilus, Bifidobacterium breve, Lactobacillus acidophilus, Bifidobacterium longum, and Lactobacillus bulgaricus) and prebiotic (fructooli-gosaccharide) and probiotic cultures [magnesium stearate (source: mineral and vegetable) and a vegetable capsule (hydroxypropyl methyl cellulose)]. Adherence was assessed by capsule counts confirmed at each visit.

These are results of this study, which monitors ALT, AST, HOMA-IR, and GGT between synbiotic group and placebo group. We can see where all parameters were started to improve in synbiotic group (compared to placebo group) since the 7th week, except ALT which was started to show significant improvement on 14th week

Similar trend was shown on inflammatory parameters, where hs-CRP, TNF-alfa, and NF-kappa-B showed significant improvement between synbiotic group and placebo group by the end of study period (week 28).

Conclusions: Synbiotic supplementation in addition to lifestyle modification is superior to lifestyle modification alone for the treat- ment of NAFLD, at least partially through attenuation of inflamma- tory markers in the body. Whether these effects will be sustained with longer treatment durations remains to be determined.