Improvement of the Bioavailability and Glycaemic Metabolism of Cinnamon Oil in Rats by Liquid Loadable Tablets

The purpose of this study is to investigate the bioavailability and glycaemic metabolism of cinnamon oil (CIO) carried by liquid-loadable tablets (CIO-LLTs), the carrier of a CIO self-emulsifying formulation (CIO-LS). The results of tests performed to evaluate the physical properties of the CIO-LLT complied with Chinese Pharmacopeia (2010). The release profile suggested that the CIO-LLT preserved the enhancement of in vitro dissolution of cio. After orally administration, the plasma concentration-time profile and pharmacokinetic parameters suggested that a significant increase (P < 0.0001) in the C(max), AUC and F were observed in the CIO-LLT. The blood glucose and the HbA1c were significantly decreased in alloxan-induced hyperglycemic rats (P < 0.05, P < 0.01, resp.), while the level of insulin secretion was markedly elevated in alloxan-induced hyperglycemic rats (P < 0.05). The alloxan-damaged pancreatic β-cells of the rats were partly recovered gradually after the rats were administered with CIO-LLT 45 days later. CIO-LLT could improve the bioavailability and glycaemic metabolism of CIO.