Red mold dioscorea decreases blood pressure when administered alone or with amlodipine and is a potentially safe functional food in SHR and WKY rats

• We investigated RMD/amlodipine antihypertensive effects and rhabdomyolysis risk.
• RMD lowered blood pressure, enhanced HDL levels, and reduced LDL-C.
• Monascus purpureus secondary metabolites monascin and GABA enhanced the antihypertension.
• RMD did not cause rhabdomyolysis or any significant metabolic abnormalities.
• RMD induced hypocholesterolemia and hypotriglyceridemia; may prevent atherosclerosis.

Hypertension is a risk factor for metabolic syndromes and cardiovascular diseases. Statins are antihypertensive, but can cause rhabdomyolysis as a side effect, which involves the breakdown of muscle fibres and release of myoglobin into the bloodstream. In this study, we used hypertensive rats to investigate whether the interaction between Monascus-fermented products (red mold dioscorea; RMD) and amlodipine increases the risk of rhabdomyolysis and toxicity. A single oral dose of RMD (176 mg/kg) significantly decreased systolic blood pressure (SBP) and diastolic blood pressure (DBP). Moreover, administration of RMD, alone or in combination with amlodipine, did not cause significant rhabdomyolysis and did not impair the metabolic or physiological functions of the liver or kidney. RMD treatment had hypocholesterolemic and hypotriacylglycerolemic effects, indicating that RMD may prevent the incidence of atherosclerosis. The findings of this study lend support to the potential use of RMD as a novel therapeutic and antihypertensive functional food.