CINNAMON
Cinnamon belongs to genus Cinnamomum, family Lauraceae which is distributed in India, Egypt, China, Srilanka and Australia. Cinnamon leaves and bark are used extensively as spices in food or to produce essential oils [50]. Studies have shown the antioxidant and antimicrobial potential [51], the antidiarrhoeal activity of Cinnamon is also well documented. The ‘Indian Materia Medica’ [52] and the ‘Indian Medicinal Plants – A Compendium of 500 species’ [53] classifies cinnamon as a herbal drug which has cardiovascular effects. Wang et al. [54] in their study using guinea pig heart showed that a decoction of cinnamon increased coronary blood flow and provoked pituitrin induced reduction of blood flow. Also it reduced peripheral vascular resistance, suggesting an undeviating vasodilation of peripheral vessels. Increased cardiac contractile force and beating rate was also exerted by cinnamaldehyde, which is present in cinnamon. Circulatory stimulant effects of cinnamon have been reported in several books on medicinal plants and also in Ayurveda [55, 56]. Dietary cinnamon increases bilary secretion of cholesterol and phospholipids without affecting the bile content (Sambaiah and Sreenivasan [42]. Sharma et al. [57] studied the effect of a 50% alcoholic extract of cinnamon on rats and reported a significant anti-hypercholesterolemic action and reduced serum triglyceride level at a single dose of 250 mg/kg body weight. Suppression of total serum cholesterol, triglycerides, phospholipids and low density lipoprotein levels was observed in another investigation using triton WR-1339-induced hyperlipidaemic rats [58]. The same group in their extension study with 80% methanolic extract and its chloroform fraction of different species of Cinnamomum observed that the extracts suppressed the elevated serum total cholesterol and triglyceride levels in corn oil-induced hyperlipidaemic rats. The chloroform fraction exhibited remarkable inhibitory effects on HMG-CoA reductase, an enzyme that catalyses cholesterol biosynthesis. Kamal [59] et al. showed in their study that cinnamon extract improved lipid profile by extensively decreasing total cholesterol, triglycerides and LDL – C levels with increasing serum HDL – C. It also hampers HMG-CoA reductase activity in liver thereby lowering the Cholesterol levels. Cinnamon activates PPARγ resulting in improved insulin resistance and reduced fasted LDL-c, thereby managing obesity related hyperlipidemia and also increases NO levels, which is a potent Vasodilator. Cinnamon demonstrated significant ability to inhibit initiation as well as propagation of lipid peroxidation due to their polyphenol content, strong reducing power and superoxide radical scavenging activity [60]. Cinnamon exhibited linear dose-dependent Nitric oxide suppressing effect without any effect upon cell viability [8]. Peroxisome proliferator-activated receptors (PPARs γ and α), one among the transcriptional factors involved in the regulation of insulin resistance and adipogenesis is found to get activated, resulting in improved insulin resistance, reduced fasted glucose, FFA, LDL-c, and AST levels in high-caloric diet-induced obesity (DIO) and db/db mice fed with cinnamon water extract