Unveiling the Metabolic Impact of Highland Barley Bran Soluble Dietary Fiber

Soluble dietary fiber (SDF) from highland barley bran soluble dietary fiber sharply reduced hepatic lipid accumulation in high‑fat‑diet (HFD)–fed mice, acting through gut microbiota modulation to lower liver lipid burden.

The investigators administered SDF to an HFD‑fed rodent cohort and measured outcomes with liver lipidomics, serum lipid panels, and 16S rDNA microbiota sequencing. Those methods identified responsive lipid species and taxonomic shifts.

SDF selectively increased the relative abundance of short‑chain fatty‑acid (SCFA)–producing taxa—most prominently Dubosiella—and raised fecal SCFAs, including acetate and propionate. SCFAs are signaling metabolites that influence hepatic energy sensing and lipid pathways, providing a link from community change to hepatic biology.

Biochemical and lipidomic readouts associated elevated SCFAs with increased hepatic AMPK α phosphorylation, altered expression of key lipogenic and oxidative enzymes, and measurable reductions in hepatic lipid stores and serum lipids. In this model, SCFA‑associated activation of AMPK signaling correlated with reduced hepatic lipid accumulation.

These rodent data support a microbiota–SCFA–AMPK mechanism by which soluble fibers improve metabolic profiles, but translational caution is warranted: human microbiota composition, dietary dose, and clinical efficacy remain untested. The next step is controlled translational trials testing SDF‑containing foods for liver fat reduction and metabolic endpoints.