Study Of Rhizome Polygonatic On Therapeutic Effect In Type 2 Diabetic And Preparation Of Sustained Release Tablets

Objective To study the therapeutic effect of Rhizome Polygonatic in type 2diabetic rats,and the prescription of Rhizome Polygonatic sustained release tablets. To determin the preparation process,check the quality and the stability of the tablets. It is expected to supply the reference to develop such TCM drugs.Methods The models of type 2 diabetic rats were set up to investigate the effect of FBG、TG、TC、LDL-C、FFAs 、HDL-C on the rats with Rhizome Polygonatic.Metformin was set as positive control.The morphological changes of liver section by HE stained and the expression of SREBP-1c and SCD-1 were determined. The appropriate prescription and preparation was designed by the orthogonal test according to the cumulative release amount. The content of Polygonatic Rhizome was determined by UV-vis spectrophotometry.The quality of the sustained release tablets was examined with the demands of Chinese Pharmacopoeia(edition 2010). The stability including influence-factor test and accelerated test was investigated.Results In 480 mg·kg-1、240 mg·kg-1 dose of Rhizome Polygonatic groups the levels of FBG,TC,TG,LDL-C,FINS decreased obviously,but HDL-C increased significantly when Compared with the model group. HE staining showed that liver fatty degeneration was significantly reduced in Rhizome Polygonaticgroups. The liver cells arranged regularly. Western Blot showed that the level of SREBP-1c was significantly reduced in Rhizome Polygonatic groups. The Prescription was designed as Rhizome Polygonatic 46 g,HPMC 9.15 g, Microcrystalline Cellulose 15 g, 20% povidone-ethanol solution and Magnesium Stearate 1%. The Rhizome Polygonatic, HPMC and Microcrystalline Cellulose were weighed according to the quantity of prescription and were mixed with equal increments. The softwoods were prepared after adding 20% povidone-ethanol solution and the wet granules were prepared by extrusion method, following with 60 ℃ dry, arranging granulars, 1% Magnesium Stearate adding, and then tableted by pelleting machine. Drug content could be accurately detected by UV-Vis spectrophotometry in Rhizome Polygonatic sustained release tablets. The appearance, weight variation, hardness and drug content were all qualified the level. The sustained release tablets were stable to high temperatures(40 ℃, 60 ℃), high humidity(75%) and high light(4500± 500 Lx), but hygroscopic to high humidity(92.5%). The sustained release tablets were stable to accelerated test(40±2 ℃, 75% ±5%) and long-term test(25±2 ℃,60%±10%).Conclusions These results suggest that Polygonatic Rhizome is effective to diabetes. It can decrease the level of blood glucose and blood lipid,and alleviate liver fatty degeneration in diabetic model rats, which probably associats to the down regulation of SREBP-1c and SCD-1 protein. The prescription and preparation of the sustained release tablets is reasonable. The determination is reliable and convenient. The quality of the sustained release tablets is according with the demands in Chinese Pharmacopoeias(Edition 2010), with better stability. It can provide reference for the further development of antidiabetic TCM drugs.