OBJECTIVETo investigate the effect of fermented barley extracts with Lactobacillus plantarum dy-1 (LFBE) for modulating glucose consumption in HepG2 cells via miR-212 regulation.

METHODSHepatocellular carcinoma (HepG2) cells were treated with palmitate. After 12 h, palmitate-induced HepG2 cells were treated with LFBE and its main components. Changes in glucose consumption, proinflammatory cytokine secretion, and miRNA-212 expression in HepG2 cells was observed.

RESULTSTreatment with LFBE rich in vanillic acid (VA) increased glucose consumption and reduced proinflammatory cytokine secretion in HepG2 cells. LFBE and VA normalized the upregulation of miR-212, which led to the upregulation of dual-specificity phosphatase-9 (DUSP9), a direct target of miR-212, at both protein and mRNA levels. Downregulation of miR-212 markedly increased glucose consumption and reduced proinflammatory cytokine secretion by enhancing DUSP9 expression.

CONCLUSIONThe results showed the benefit of LFBE and miR-212 downregulation in modulating glucose consumption and reducing proinflammatory cytokine secretion by targeting DUSP9. VA in LFBE was a strong regulator of palmitate-induced abnormal glucose consumption in HepG2 cells and can be a primary mediator.