Hypolipidemic and Antihyperlipidemic Effects of Holarrhena pubescens Methanolic Extract Is Mediated through Inhibition of Lipase Activity and Lipid Accumulation.

Holarrhena pubescens seeds are used in the treatment of various diseases, especially diabetes and associated complications, in different parts of the world. The present study was undertaken to determine the hypolipidemic and antihyperlipidemic effects of methanolic extract of H. pubescens seeds in rats. The extract was subjected to LC-MS analysis to determine the chemical constituents. The hypolipidemic action was studied by determining the effect of 28-day oral administration of seed extract on serum cholesterol, serum triglycerides, and serum HDL-cholesterol levels. The antihyperlipidemic action was studied in rats fed with a high-fat diet containing cholesterol and saturated fat, and the same lipid parameters were estimated during 28-day treatment. To elucidate its probable mechanism of action, in vitro studies on the inhibition of lipid accumulation in preadipocytes, DPP-IV inhibitory effect, and lipase enzyme inhibition were studied. The seed extract reduced serum levels of cholesterol and triglycerides in both normal rats and animals fed with a high-fat diet without a significant effect on HDL-cholesterol levels. The seed extract was highly effective in inhibiting lipase enzyme activity but showed a modest effect on the inhibition of lipid accumulation and DPP-IV. The results demonstrated that H. pubescens seed extract has hypolipidemic and antihyperlipidemic effects mediated probably through inhibition of lipase enzyme activity.

The antidiabetic effect of methanolic extract of Holarrhena pubescens seeds is mediated through multiple mechanisms of action.

Holarrhena pubescens is widely used in Indian and Chinese medicine in the treatment of diabetes. The current work determined the oral hypoglycemic and antidiabetic effects of seed extract in rats. The probable mechanism of action was evaluated in-vitro by α - glucosidase inhibition, glucose metabolism in insulinoma (INS-1) cells to reflect secretion of insulin, and protein glycation inhibition. Its potential for herb-drug interaction was evaluated in the cytochrome P450 3A4 (CYP3A4) inhibition assay. The seed extract increased serum insulin levels and reduced serum blood glucose levels in the oral glucose tolerance test. It also reduced the serum glucose levels in streptozocin-induced diabetes. The extract also inhibited α -glucosidase enzyme activity and demonstrated that it can increase the secretion of insulin from INS to 1-rat insulinoma cell line cells in-vitro in a concentration-dependent manner. However, it had a very weak inhibitory effect on protein glycation and it did not affect the activity of CYP3A4. The results of the study showed that H. pubescens seed extract increases insulin secretion and inhibits glucose absorption both in-vivo and in-vitro with a weak protein glycation inhibitory effect. The herb is devoid of CYP3A4 inhibitory effect indicating that it may not have pharmacokinetic interaction with the drug metabolized by this enzyme.

Beneficial Effect of Methanolic Extract of Frankincense (Boswellia Sacra) on Testis Mediated through Suppression of Oxidative Stress and Apoptosis.

Boswellia sacra oleo gum resin (Burseraceae) commonly known as frankincense is traditionally used in many countries for its beneficial effect on male fertility. This study explores its effect on the male reproductive system after a 60-day repeated administration at two different doses to rats (in vivo) and on human Leydig cells (in vitro). The methanolic extract of B. sacra was analyzed for the presence of various constituents by preliminary phytochemical analysis and gas chromatography-mass spectrometry (GC-MS) while quantitative analysis of boswellic acids was done by high-performance liquid chromatography (HPLC). Administration of B. sacra extract to rats elevated the serum testosterone levels with an associated reduction in serum levels of FSH and LH. An increase in the activity of antioxidant enzymes, superoxide dismutase and catalase, was seen. A dose-dependent increase in the sperm count and sperm motility was also observed. The in vivo results were supported by changes in the expression of the Bcl-2 gene and caspase-3 gene in human Leydig cells in vitro. The results of this study support the traditional use of B. sacra to increase male fertility.

Frankincense extract protects against testicular damage through augmentation of antioxidant defense mechanisms and modulation of apoptotic genes expression.

Frankincense (Boswellia sacra Fluck.,) is traditionally used in the treatment of altered male fertile potential in several countries. This study evaluated the cytoprotective action of B. sacra oleo gum resin extract against cyclophosphamide (CP) induced testicular toxicity in rats (in-vivo) and lipopolysaccharide (LPS) induced cytotoxicity in human Leydig cells (in-vitro). The methanolic extract of B. sacra was standardized for the presence of different boswellic acids using high-performance liquid chromatography (HPLC) and volatile constituents in the extract were detected by gas chromatography-mass spectrometry (GC-MS). Two doses of B. sacra extract were used in the in-vivo study. The HPLC analysis showed that extract contains about 36% w/w of total boswellic acids and GC-MS analysis revealed the presence of another 71 different constituents. Administration of B. sacra extract to rats increased serum testosterone levels, antioxidant enzyme activities, and sperm count with improved sperm quality in a dose-dependent manner, when compared to CP treated animals. Boswellia sacra extract also protected the human Leydig cells against LPS-induced damage and increased the expression of the Bcl-2 gene along with a decrease in caspase-3 gene expression. The results of this study show that B. sacra extract has a protective effect on the male reproductive system.