Ardipusilloside-I stimulates gastrointestinal motility and phosphorylation of smooth muscle myosin by myosin light chain kinase

Ardipusilloside-I is a natural triterpenoid saponin, which was isolated from Ardisia pusilla A. DC. The aim of the study was to evaluate the stimulation of ardipusilloside-I on gastrointestinal motility in vitro and in vivo. The experiment of smooth muscle contraction directly monitored the contractions of the isolated jejunal segment (IJS) in different contractile states, and the effects of ardipusilloside-I on myosin were measured in the presence of Ca²⁺-calmodulin using the activities of 20 kDa myosin light chain (MLC₂₀) phosphorylation and myosin Mg²⁺-ATPase. The effects of ardipusilloside-I on gastro emptying and intestinal transit in constipation-predominant rats were observed, and the MLCK expression in jejuna of constipated rats was determined by western blot. The results showed that, ardipusilloside-I increased the contractility of IJS in a dose-dependent manner and reversed the low contractile state (LCS) of IJS induced by low Ca²⁺, adrenaline, and atropine respectively. There were synergistic effects on contractivity of IJS between ardipusilloside-I and ACh, high Ca²⁺, and histamine, respectively. Ardipusilloside-I could stimulate the phosphorylation of MLC₂₀ and Mg²⁺-ATPase activities of Ca²⁺- dependent phosphorylated myosin. Ardipusilloside-I also stimulated the gastric emptying and intestinal transit in normal and constipated rats in vivo, respectively, and increased the MLCK expression in the jejuna of constipation-predominant rats. Briefly, the findings demonstrated that ardipusilloside-I could effectively excite gastrointestinal motility in vitro and in vivo.

Effects of Deoxyschisandrin on Hemorrheology and Coagulation Function in Ulcerative Colitis Mice / 现代生物医学进展

Objective:To observe the effects of Deoxyschisandrin on hemorrheology and coagulation function in ulcerative colitis (UC)mice.Methods:Trinitrobenzenesulfonic acid (TNBS)induced UC mice model was prepared.And then UC mice were randomly divided into model group,positive control group,high,medium,and low dose groups of deoxyschisandrin (80,40,20mg/kg),and in addition,a normal control group was set up.There were 10 mice in each group respectively.UC mice were intragastricly administrated with different concentration of deoxyschisandrin in medication group,or with equal volume distilled water in normal group or model group,respectively.The blood viscosity was determined by blood rheometer,and the bleeding time (BT)and the clotting time (CT)were also observed through the methods of tail cutting and blood coagulation in glass plates accordingly.Results:Compared with model group,the BT (P ＜ 0.01)and CT (P ＜ 0.05)were significantly prolonged,and the blood viscosity was decreased obviously (P ＜ 0.05) in UC mice after administrated with different concentration deoxyschisandfin for 14 days.And the effects in high dose group were strongest and similar to those in the positive group.Conclusions:Deoxyschisandrin can improve hemorrheology and coagulation function in UC mice.