Protective effects of Dendrobium officinale superfine powder against LPS-induced intestinal mucosal injury in mice / 中国中药杂志

This study aims to investigate the preventive effect of Dendrobium officinale in LPS-induced intestinal mucosal damage. Forty SPF-grade C57 BL/6 J male mice were randomly divided into normal group(NC), model group(LPS), and two superfine powder groups of Dendrobium officinale(DOF)(DOF-L, 0.30 g·kg~(-1)and DOF-H, 0.60 g·kg~(-1), respectively), with 10 mice in each group. DOF superfine powder suspension was given via oral administration to mice for 7 days, while the mice in NC and LPS groups received the same volume of saline for 7 days. On the eighth day, the mice in LPS group and DOF treatment groups were injected with LPS(5 mg·kg~(-1)) by intraperitoneal injection to establish the intestinal mucosal injury model, while the mice in NC group were injected with the same volume of sterile saline in the same manner. Six hours after injection with LPS or saline, plasma and the intestinal tissue were collected. The diamine oxidase(DAO) and D-lactate levels in plasma were detected with a biochemical method. The levels of proinflammatory factors interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α) in plasma were detected by ELISA. The histomorphology and ultrastructure of mouse ileum tissues were observed by hematoxylin-eosin(HE) staining in optical microscope and transmission electron microscope(TEM). The expression and distribution of tight junction(TJ) proteins claudin-1, occludin and F4/80 were detected by immunohistochemistry while the protein expression levels of Toll-like receptor 4(TLR-4) and nuclear factor kappa B p65(NF-κB p65) in jejunum were detected by Western blot. The experimental results showed that continuous intragastric administration of D. officinale superfine powder for 7 days obviously alleviated the damage and ultrastructural changes of intestinal mucosa induced by LPS; significantly decreased DAO and D-lactate levels in plasma in model group(P<0.05); up-regulated the protein expression of claudin-1 and occludin in ileum tissues; down-regulated the protein expression of TLR-4 and NF-κB p65 in jejunum tissues(P<0.01); significantly decreased TNF-α and IL-6 levels in plasma(P<0.05); and decreased the infiltration of F4/80~+ macrophage cells. Our results suggested that D. officinale had significant protective effects on LPS-induced intestinal mucosal damage and reduced intestinal permeability. The mechanism might be related to its effects of inhibiting inflammation via TLR-4/NF-κB p65, and up-regulating the expression of tight junction proteins.

Chitosan modified material and its application in hemostasis: research advances / 国际药学研究杂志

Chitosan(CS)is the product of chitin derived by removal of some acetyl groups, which is non-toxic, safe and biodegradable. It is easily obtainable and has wide application prospects. However, due to its intramolecular hydrogen bonding and spatial configuration of macromolecules, CS is not easily soluble in water and organic solvents, so its application is limited. For its extended application, CS is often modified or compounded with other materials. This article briefly summarizes the modification methods of CS, including acylation, etherification, alkylation, quaternization, graft copolymerization, etc., and introduces the application of CS composite materials in hemostasis.

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.