Antihyperlipidemic effects of stilbenoids isolated from Morus alba in rats fed a high-cholesterol diet

•Mulberroside A from Morus alba reduced the levels of serum lipids.•Oxyresveratrol produced by enzymatic conversion of mulberroside A significantly reduced the levels of serum lipids.•Both stilbenoids improved the hepatic fatty acid degeneration in high cholesterol diet-induced hyperlipidemic rats.

Mulberroside A (MUL) was purified from an ethanol extract of Morus alba root, and oxyresveratrol (OXY) was produced by enzymatic conversion of MUL. Normal rats, Triton WR-1339-induced hyperlipidemic rats, and high-cholesterol diet (HCD)-induced hyperlipidemic rats were orally treated with MUL or OXY (1−5 mg/kg/day). MUL and OXY were administered 1 h prior to concomitant treatment with Triton WR-1339 for a further 24 h, whereas the drugs were administered concurrently with HCD for 4 weeks. Oral MUL and OXY pre-treatment vs. water pre-treatment of Triton WR-1339-induced hyperlipidemic rats significantly (p < 0.05) reduced the levels of serum lipids in a dose-dependent manner, while high-density lipoprotein cholesterol (HDL-C, or “good” cholesterol) levels were increased. Oral MUL and OXY treatment of HCD-fed rats also showed a significant (p < 0.05) dose-dependent decrease in serum lipids, coronary artery risk index (CRI), and atherogenic index (AI), but not HDL-C. Furthermore, MUL and OXY treatment of HCD-induced hyperlipidemic rats demonstrated a significant dose-dependent improvement in the histological features of hepatic fatty degeneration. Aspartate aminotransferase and alanine aminotransferase values in OXY-treated normal rats were not significantly different from those in water-treated control rats. These results indicate that MUL and OXY might be developed as novel antihyperlipidemic agents.

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