| Bombax malabaricum DC.is a large deciduous tree growing in tropical and subtropical regions,such as southern China.The flower of this plant is used not only as a traditional Mongolian medicine,but also as an important raw material of herbal tea with functions of clearing heat,detoxifying and relieving heat,clearing damp etc.The flower mainly contains flavonoids,phenolic acids,phenylpropanoids,fatty acids,amides and other compounds.B.malabaricum flower has been found to have the effects of anti-oxidation,anti-virus,lipid-lowering,hypoglycemic,anti-helicobacter pylori etc.So far,there are few reports on its use in the treatment of diabetes.Studies have shown that flavonoids with antioxidant activity can enhance the antioxidant capacity of the oxidation system,regulate the disorder of glucose and lipid metabolism in diabetes,and improve the function of pancreatic β cells,so as to have a certain therapeutic effect on diabetes and the complications.As the extract of B.malabaricum flower contains a large number of flavonoids with antioxidant capacity,this research will study the anti-diabetes effect and possible in vivo bioactive constituents of the extract of B.malabaricum flower.In this experiment,the optimal extraction process of B.malabaricum flower was investigated,and the main components were detected and quantitativelyanalyzed by UHPLC-MS.The composition and contents of each compound in the extracts were compared,and a total of 18 compounds were detected: mangiferin,muraxanthone,rutin,quercetin,isoquercetin,N-(E)-p-coumaroyltyrosine,N-(Z)-p-coumaroyltyrosine,orientin,isoorientin,vitexin,isovitexin,scopoletin,gallic acid,protocatechuic acid,chlorogenic acid,citric acid,quinic acid,caffeic acid.Quantitative analysis revealed that the chromatogram peak areas of most of these compounds in UHPLC-MS were of the largest when 80% EtOH was used as solvent and extracted under reflux.Finally,80% EtOH under reflux was determined as the optimal extraction method for B.malabaricum flower.The effects of B.malabaricum flower extract on the body weights,blood glucose level,and liver antioxidant capacity of the diabetic rats induced by streptozotocin were investigated.The results showed that B.malabaricum flower extract significantly reduced the blood glucose level,improved the decreasing trend of body weight gain in the diabetic rats,significantly decreased liver MDA and GSH-px levels,and increased SOD activity.Therefore,B.malabaricum flower could not only decrease the level of blood glucose,but also enhance the antioxidant capacity of liver tissues in diabetic rats.The pharmacokinetic properties in normal and diabetic rats of these 18 compounds from B.malabaricum flower were evaluated and compared.The results showed that 12 compounds could be detected in the blood of normal rats and 13 compounds detected in the blood of diabetic rats.The pharmacokinetic parameters of B.malabaricum flower constituents were significantly changed in the pathological state of diabetes mellitus.Compared with normal rats,diabetic rats absorbed more B.malabaricum flower constituents in blood.Combination with Termianlia chebula fruits could also change the pharmacokinetics of B.malabaricum flower constituents.Studies have shown that diabetes can lead to the disorder of intestinal flora,which plays an important role in drug absorption,biotransformation and metabolism.Therefore,the metabolism of the intestinal flora of normal and diabetic rats on the major chemical constituents of B.malabaricum flower,including rutin,quercetin andmangiferin,were investigated in vitro.Through UHPLC-MS analysis,it was found that the intestinal flora of both the normal and diabetic rats could decompose rutin,quercetin and mangiferin,among which the decomposition of rutin was the most obvious.The normal group decomposed rutin completely in 12 h,while the diabetic rats could not decompose rutin completely until 24 h,indicating that the intestinal flora of diabetic rats was weak in decomposing rutin,which may be because the intestinal flora of diabetic rats was reduced.To sum up,this study investigated the anti-diabetes effects of B.malabaricum flower extract and the pharmacokinetic properties of its main components.The results showed that the ethanol extract of B.malabaricum flower has anti-diabetes effect.The flavonoids,which have high bioavailability are deduced to be the main pharmacodynamic components of B.malabaricum flower. |
PDF Full Text Request