Molecular Targets and Health Benefits of Cinnamon
Common cinnamon (Cinnamomum verum, C. zeylanicum) and cassia (C. aromaticum) have a long history of uses as spices, flavoring agents, preservatives, and pharmacological agents. Recent studies also demonstrate that compounds found in cinnamon improve the function of insulin, function as antioxidants, anti-inflammatory agents, and may be neuroprotective. Human studies involving control subjects, subjects with the metabolic syndrome, type 2 DM, and polycystic ovary syndrome show beneficial effects of whole cinnamon and aqueous extracts of cinnamon on glucose, insulin, insulin sensitivity, lipids, antioxidant status, lean body mass and gastric emptying. In vitro and animal studies demonstrate that aqueous extracts of cinnamon, high in type A polyphenols, increase insulin receptor efficiency by increasing tyrosine phosphorylation and decreasing phosphatase activity, leading to increased insulin sensitivity; increase the amounts of insulin receptor, glucose transporter and anti-inflammatory tristetraprolin proteins; increase glycogen synthase activity and glycogen accumulation; regulate inflammatory responses and exert neuroprotective effects against amyloid beta or oxygen-glucose deprivation induced neural damage. Thus cinnamon, and its components, may be important in the alleviation of chronic diseases associated with insulin resistance such as type 2 diabetes, inflammatory and cardiovascular diseases and neuroprotective effects on stroke and Alzheimer's disease.