Simvastatin

Simvastatin

Introduction

Simvastatin is commonly known as Zocor, which is its trade name. It is a hypolipidemic drug that is usually taken in order to control increased cholesterol level or hypercholesterolemia. It is the member of Statin class of pharmaceuticals (Nelson, 2008). It is basically a synthetic derivative of the fermentation product of Aspergillus terreus. Together with the weight loss, appropriate diet plans and exercise the drug is used to decrease the quantity of fatty materials for e.g. Low density lipoprotein also known as LDL cholesterol and triglycerides concentration in the blood in order to increase the concentration of high-density lipoprotein (HDL) cholesterol in the blood. Basically it is used in dyslipidemia, in order to prevent the potent cardio vascular diseases.

Discussion

The Chemical Structure of Simvastatin

Simvastatin is C25H3805 418.57. It is comprised of 2 ester groups (1 cyclic, 1 non cyclic), A hydroxy group, fused non-aromatic ring system. The structural formula is represented

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The Mode of Action, Pharmacodynamics and Pharmacokinetics

Simvastatin like other statins follow the mechanism of inhibition. It is quickly hydrolyzed in vivo to produce mevinolinic acid. Mevinolinic acid is a very strong inhibitor of HMG-CoA Reductase also referred as HMGR. HMG-CoA Reductase is an enzyme abundantly found in the body, it is responsible for the synthesis of cholesterol. It is an essential component in the synthetic steps of cholesterol. It acts as the competitive inhibitor thereby inhibiting the activity of HMG-CoA Reductase, as it is the rate limiting enzyme in cholesterol synthesis procedure the rate of cholesterol production is significantly reduced. Like other statins, Simvastatin forms number of polar bond with HMG-CoA Reductase in order to bind itself. The polar bond interacts with the cis loop of HMGR (Schachter, 2004).

The reduction in the concentration of cholesterol initiates a cellular signaling flow that activates the sterol regulatory element binding protein referred as SREBP. SREBP is a factor in transcription that brings about the gene encoding the Low density lipoprotein receptor. When the LDL reception expression increases, the uptake of plasma LDL also increases, this leads to decreased concentration of plasma Low density lipoprotein cholesterol (Piepho, 2000).

Simvastatin is highly absorbable and from the gastro intestinal tract, the drug is efficiently absorbed by both active and passive transport. However majority of the drug is filtered off by the liver and around seven percent of the total dose reaches the general circulation. Within two to four hours of the consumption the ...