Effect of Dendrobii officinalis superfine powder on overeating greasy-induced metabolic hypertension in rats / 中国中药杂志

Dendrobii officinalis, with a definite effect of nourishing Yin and clearing heat, has been a folk habit for drinking after being mixed with water. Because its superfine powder has the advantages of high dissolution and convenient drinking, we observed the effect of D. officinalis superfine powder on metabolic hypertension model rats and its possible mechanism in this experiment, which can be used as a reference for its clinical application for hypertension. The overeating greasy-induced metabolic hypertension model was established with high-fat, high-sugar and high-purine diet. These rats were orally administered with 400 mg·kg~(-1) and 200 mg·kg~(-1) of D. officinalis superfine powder for 20 consecutive weeks. During this period, blood pressure, blood lipid, blood glucose, insulin and other related indexes of glucose and lipid metabolism were monitored; the levels of lipopolysaccharide(LPS), C-reactive protein(CRP), interleukin 6(IL-6) and other inflammatory mediators were measured; the levels of nitric oxide(NO) and endothelin-1(ET-1) were detected, and the histomorphological and ultrastructural changes of aorta were observed. In addition, the expression of LPS/TLR4 pathway-related molecules in aorta was determined. The results showed that long-term administration of D. officinalis superfine powder significantly reduced the levels of systolic blood pressure(SBP), diastolic blood pressure(DBP) and mean arterial pressure(MBP) in metabolic hypertension model rats, decreased the levels of total cholesterol(TC), triglyceride(TG), low density lipoprotein cholesterol(LDL-c), glucose(Glu), and insulin(INS) levels in blood, increased the contents of high density lipoprotein cholesterol(HDL-c),decreased the LPS, CRP, IL-6 and ET-1 levels in blood and increased NO content. Furthermore, it improved the abnormality of aortic histomorphology and endothelial ultrastructure, and inhibited the protein expression of TLR4, myeloid differentiation factor(MyD88), IL-6, interleukin-1 β(IL-1β), and tumor necrosis factor-α(TNF-α) as well as mRNA expression of TNF-α and IL-1β in aorta. In conclusion, D. officinalis superfine powder may improve the abnormal function and structure of blood vessels by inhibiting the activation of LPS/TLR4 pathway, thus playing a role against metabolic hypertension.

Effects and active substances of ethanol extract from Dendrobium officinale on metabolic hypertensive rats induced by comprehensive dietary / 中国中药杂志

Previous studies of Dendrobium officinale on anti-hypertension effect always focused only on the blood pressure,while polysaccharides of D. officinale( DOP) have been traditionally considered as one of the main effective substances. This study aimed to evaluate the effect of ethanol extract from D. officinale( DOE) on blood pressure,Glu and lipid profile in metabolic hypertensive rats induced by comprehensive dietary factors,and elucidate the composition of effective fractions from DOE. A metabolic hypertension model of rat induced by high-sugar,high-fat diet and alcohol drinking was adopted to evaluate the effect of DOE on hypertension and other metabolic disorders. Blood pressure,Glu and lipid profile were detected to find the features and differences of DOE and DOP on metabolic hypertension. Furthermore,DOE was separated with three different common solvents according to the polarity. Along with blood pressure,Glu,UA and lipid profile,hemorheology,oxidative index and aortas structure changes were adopted to evaluate the comprehensive effects of the most effective fractions on metabolic hypertension. Finally,HPLC-DAD-MS was adopted to identify the components of the most effective fraction. The SBP and Glu of models were decreased significantly after administration of DOE and DOP for 6 weeks,while TG in DOE groups also reduced dramatically. The DOE was separated with ether,n-butanol respectively and named NAF,NBF and NCF. SBP,TG,Glu,UA of model rats were decreased significantly after 4 weeks administration with NBF. The level of MDA in serum was down-regulated,while GSH-Px and T-AOC were up-regulated obviously after 12 weeks.And the blood viscosity also obviously decreased,with less collagen deposition of aortas by Masson's trichrome staining. NBF was mainly composed of phenols and flavone C-glycosides,whose aglycone was apigenin,and monosaccharide was connected to C-6 and C-8. Ethanol extract from D.officinale has an positive effect in alleviating hypertension and metabolic disorders in metabolic hypertension. Medium polarity fraction was the effective fraction of alcohol extraction from D. officinale,and mainly composed of phenols and flavone C-glycosides.

Current situation and prospect of antihypertensive pharmacology of traditional Chinese medicine / 中国药理学与毒理学杂志

The incidence and its growth rate of hypertension are both very high. Its pathology and pathogenesis are complex and unclear,and it does serious harm to human health. Hypertension remains incurable. Chemical medicine has good effect on hypertension,but life-long application and multi-drug combination are required,with significant adverse reactions. Also,complications can′t be effectively alleviated. Traditional Chinese medicine (TCM)guided by traditional theories,can lower blood pressure,improve metabolic abnormalities and reduce complications. Its advantages or potentials have not been fully exploited and clinical application is inadequate. Metabolic hypertension has become the main form of hypertension,and its formation mechanism is mainly related to metabolic abnormalities and insulin resistance,metabolic inflammation and other pathology and pathogenesis. A better understanding of the current status of antihypertensive pharmacology of TCM,especially devel?opment and application of metabolic hypertension models is of great significance for TCM treatment of hypertension,and for exploration of new approaches to hypertension.