ABSTRACT
Objective To investigate the anti-ulcer effects of Albizia chinensis(Osbeck)Merr. extract on rats with acetic acid-induced chronic gastric ulcer and explore the anti-inflammatory mechanism. Methods Wistar male rats(n=50)were randomized in-to five groups:control,model,famotidine,Albizia chinensis extract 100 and 200 mg/kg groups. In the experiment,30%acetic acid was used to induce chronic gastric ulcer in rats. The anti-ulcer effects of A. chinensis extract were evaluated by measuring the changes in general behavior of rats,gastric tissue morphology and the ulcer area after 12 d treatments. Wistar male rats(n=48)were random-ized into three groups:control,model and A. chinensis extract(200 mg/kg)groups. At 3 d after operation,the animals were sacrificed and stomachs were rapidly removed and processed for subsequent assays. The contents of TNF-αand IL-6 were evaluated by ELISA. The activity of myeloperoxidase(MPO)was tested by o-dianisidine method. Furthermore Western blot was used to examine the phos-phorylation of P38 and JNK. Results Compared with the model group,the gastric ulcer areas of rats were reduced by 38.4%(P<0.05)and the activity of MPO declined by 37.3%(P<0.01)in A. chinensis extract(200 mg/kg)group. Meanwhile the contents of TNF-αand IL-6 in A. chinensis extract(200 mg/kg)group respectively decreased by 43.8%(P<0.01)and 32.7%(P<0.01)com-pared with the model group. A. chinensis extract(200 mg/kg)obviously suppresed the phosphorylation of P38(P<0.01),but phos-phorylation of JNK and expression of P38 and JNK remained nearly unaltered. Conclusion A. chinensis extract(200 mg/kg)exhibits a protective effect on acetic acid-induced chronic gastric ulcer,which might be relevant to anti-inflammation by inhibiting the p38 sig-naling pathway but not JNK signaling pathway. A. chinensis extract(200 mg/kg)has no effect on JNK signaling pathway.
ABSTRACT
Objective To investigate the gastric protective effect of Albizia chinensis extract on acute gastric ulcer model in rats and its mechanism related to H+,K+-ATPase in gastric parietal cells. Methods Rats were injected intraperitoneally with indo?metacin or kept under water immersion-restraint stress(WRS)to establish acute gastric ulcer model. Test samples were orally given 30 min before induction of gastric ulcer,and the gastric ulcer index and inhibitory rate were used to evaluate the effect of A. chinensis extract. Gastric mucosa pathological tissues in rats were observed by HE staining,the enzymatic activity of proton pump on isolated gastric parietal cells was measured,and the translocation of gastric proton pump was observed by immunofluorescence cell staining. Results The A. chinensis extract inhibited the gastric ulcer with the inhibition rate of 70.0%and 75.4%at 300 mg/kg in the WRS and indomethacin-induced rat model,respectively. The extract could also inhibit the enzymatic activity of gastric proton pump with the in?hibition rate of 21.5%,29.4%,44.1%,51.9%,57.7%and 62.9%(P<0.01)at 15,30,60,120 and 480 mg/L,respectively. The half-effective dosage(ID50)of the extract was determined to be 130 mg/L. The extract showed no significant effect on the translocation of gastric proton pump. Conclusion The A. chinensis extract(300 mg/kg,ig)could significantly prevent the formation of gastric ul?cer in rats via inhibiting the enzymatic activity of gastric proton pump.