In vitro activity: Mevastatin is a cholesterol-lowering agent isolated from Penicillium citinium. It reduces cholesterol synthesis to 50% of control at 0.01 pg/mL (26 nM). It is structurally similar to the HMG, a substituent of the endogenous substrate of HMG-CoA reductase. Mevastatin is a prodrug that is activated in vivo via hydrolysis of the lactone ring. The hydrolyzed lactone ring mimics the tetrahedral intermediate produced by the reductase allowing the agent to bind with 10,000 times greater affinity than its natural substrate. The bicyclic portion of mevastatin binds to the coenzyme A portion of the active site. Mevastatin increases levels of eNOS mRNA and protein, reduces infarct size, and improves neurological deficits in a dose- and time-dependent manner.
Kinase Assay: Mevastatin inhibits HMG-CoA reductase reversibly and competes with HMG-CoA. It shows a Ki value of about 1nM.
Cell Assay: Mevastatin inhibits sterol synthesis from acetate in various cells at low concentration of nanomolar. It also inhibits acetate incorporation with IC50 value of 1nM. Besides that, mevastatin completely suppresses the growth of L cells at 1.3μM. Mevastatin is also found to affect the cell cycle and change cell morphology in cultured fibroblasts. | 
