OBJECTIVEMyriocin (ISP-1) is a new type of immune inhibitor extracted from cordyceps sinensis. This study was to observe the effects of ISP-1 on the expression of cell cycle regulatory protein D1 (cyclinD1) in high glucose-induced hypertrophy rat glomerular mesangial cells (GMCs).

METHODSRat GMCs were cultured in vitro and divided into three groups: high glucose (450 mg/dL D-glucose), normal glucose (100 mg/dL D-glucose, control) and ISP-1 (450 mg/dL D-glucose plus 100 μg/mL ISP-1). The protein expression of cyclinD1 was detected by flow cytometry.

RESULTSThe expression of cyclinD1 in GMCs in the high glucose group increased significantly in a time-dependent manner compared with that in the control group. ISP-1 treatment significantly inhibited the up-regulated expression of cyclinD1 induced by high concentration glucose, and the expression of cyclinD1 was restored to the level of the control group 48 and 72 hrs after ISP-1 treatment.

CONCLUSIONSHigh concentration of glucose can up-regulate the expression of cyclinD1 in GMCs. ISP-1 may inhibit the up-regulated expression of cyclinD1, which might contribute to the protective effect of ISP-1 against GMC hypertrophy induced by high glucose.