Rifaximin on epigenetics and autophagy in animal model of hepatocellular carcinoma secondary to metabolic-dysfunction associated steatotic liver disease.

BACKGROUND: Prevalence of hepatocellular carcinoma (HCC) is increasing, especially in patients with metabolic dysfunction-associated steatotic liver disease (MASLD).

AIM: To investigate rifaximin (RIF) effects on epigenetic/autophagy markers in animals.

METHODS: Adult Sprague-Dawley rats were randomly assigned ( n = 8, each) and treated from 5-16 wk: Control [standard diet, water plus gavage with vehicle (Veh)], HCC [high-fat choline deficient diet (HFCD), diethylnitrosamine (DEN) in drinking water and Veh gavage], and RIF [HFCD, DEN and RIF (50 mg/kg/d) gavage]. Gene expression of epigenetic/autophagy markers and circulating miRNAs were obtained.

RESULTS: All HCC and RIF animals developed metabolic-dysfunction associated steatohepatitis fibrosis, and cirrhosis, but three RIF-group did not develop HCC. Comparing animals who developed HCC with those who did not, miR-122, miR-34a, tubulin alpha-1c (Tuba-1c) , metalloproteinases - 2 (Mmp2) , and metalloproteinases - 9 (Mmp9) were significantly higher in the HCC-group. The opposite occurred with Becn1 , coactivator associated arginine methyltransferase-1 ( Carm1 ), enhancer of zeste homolog-2 ( Ezh2 ), autophagy-related factor LC3A/B (Map1 Lc3b) , and p62/ sequestosome-1 ( p62/ SQSTM1 )- protein . Comparing with controls, Map1 Lc3b , Becn1 and Ezh2 were lower in HCC and RIF-groups ( P < 0.05). Carm1 was lower in HCC compared to RIF ( P < 0.05). Hepatic expression of Mmp9 was higher in HCC in relation to the control; the opposite was observed for p62/Sqstm1 ( P < 0.05). Expression of p62/SQSTM1 protein was lower in the RIF-group compared to the control ( P = 0.024). There was no difference among groups for Tuba-1c , Aldolase-B, alpha-fetoprotein, and Mmp2 ( P > 0.05). miR-122 was higher in HCC, and miR-34a in RIF compared to controls ( P < 0.05). miR-26b was lower in HCC compared to RIF, and the inverse was observed for miR-224 ( P < 0.05). There was no difference among groups regarding miR-33a, miR-143, miR-155, miR-375 and miR-21 ( P > 0.05).

CONCLUSION: RIF might have a possible beneficial effect on preventing/delaying liver carcinogenesis through epigenetic modulation in a rat model of MASLD-HCC.