Effect of vitamin D on bioavailability and lipid lowering efficacy of simvastatin.

The 3-hydroxy 3-methylglutaryl coenzyme A reductase (HMG-CoA reductase) inhibitors known as "statins" are widely prescribed for the management of dyslipidemia. In spite of their muscle toxicity, use of statins has alarmingly increased worldwide. A recent report suggests that vitamin D (VD) levels are closely associated with lipid lowering activity and muscular toxicity of statins. However, data are limited and inconclusive. The present study was undertaken to investigate the effect of VD supplementation on the bioavailability and lipid lowering effect of simvastatin (ST). Adult Sprague-Dawley male rats (250 ± 10 g) were divided into four groups including control, ST (100 mg/kg/day), VD (100 µg/kg/day) and ST + VD group, respectively. After the dosing period of 8 days the animals were sacrificed and the blood was collected for the analysis of ST, its active metabolite simvastatin acid (STA), total cholesterol, triglyceride and liver enzymes including aspartate transaminase and alanine transaminase. The result of this study showed a significant decrease in the level of cholesterol and triglyceride in ST alone treated group, whereas VD alone failed to alter the blood lipid levels. Concomitant treatment with VD produced significant decrease in the bioavailability of ST and STA. However, there was no significant difference in the level of cholesterol in ST alone and in ST + VD treated group. Our results on the liver enzyme suggest that ST alone or in combination with VD does not produce any hepatotoxicity. Further studies using VD along with various statins for a longer duration are suggested.

A review of hepatoprotective plants used in saudi traditional medicine.

Liver disease is one of the major causes of morbidity and mortality across the world. According to WHO estimates, about 500 million people are living with chronic hepatitis infections resulting in the death of over one million people annually. Medicinal plants serve as a vital source of potentially useful new compounds for the development of effective therapy to combat liver problems. Moreover herbal products have the advantage of better affordability and acceptability, better compatibility with the human body, and minimal side effects and is easier to store. In this review attempt has been made to summarize the scientific data published on hepatoprotective plants used in Saudi Arabian traditional medicine. The information includes medicinal uses of the plants, distribution in Saudi Arabia, ethnopharmacological profile, possible mechanism of action, chemical constituents, and toxicity data. Comprehensive scientific studies on safety and efficacy of these plants can revitalise the treatment of liver diseases.