目的 通過幽門螺桿菌(Hp)感染小鼠建立Hp相關胃炎模型,探討豬苓多糖的保護作用及機制。方法 將C57BL/6小鼠隨機分為4組:對照組、模型組、豬苓多糖(250 mg·kg^-1)組、核轉錄因子-κB (NF-κB)通路的抑制劑——吡咯烷二硫代甲酸銨(PDTC,陽性對照,100 mg·kg^-1)組。除對照組外,其余各組小鼠ig給予Hp悉尼株1(SS1)菌液(1×10⁹ CFU·mL^-1),第1天每只0.4 mL,以后連續(xù)3 d每天ig 1次,每次0.2 mL。ig Hp完成4周后,豬苓多糖組和PDTC組給予相應劑量的藥物,對照組和模型組小鼠給予無菌水,每只0.4 mL,每天1次持續(xù)14 d。將胃取出,沿胃大彎切開,肉眼觀察胃黏膜變化;吉姆薩染色驗證Hp在小鼠胃黏膜的定植;HE染色觀察小鼠胃黏膜組織的炎癥浸潤狀態(tài);免疫組化檢測核因子-κB(NF-κB) p65的表達;Western blotting法檢測小鼠胃腺組織炎癥因子白細胞介素-8(IL-8)蛋白表達;酶聯(lián)免疫吸附法(ELISA)檢測小鼠血清中IL-8的表達。結果 與模型組比較,豬苓多糖組小鼠胃黏膜褶皺整齊,出血點消失,黏膜光滑,胃黏膜顏色紅潤有光澤;炎癥細胞浸潤和其他組織損傷明顯減少;細菌定植數(shù)量明顯減少;胃上皮細胞中NF-κB p65的表達減弱;胃腺組織IL-8蛋白表達水平顯著降低(P<0.001);小鼠血清中IL-8表達水平顯著降低(P<0.001)。結論 豬苓多糖可能通過抑制炎癥信號通路NF-κB相關分子的表達在Hp相關胃炎中發(fā)揮保護作用。

Objective To investigate the protective effect and preliminary mechanism of Polyporus polysaccharide (PPS) in Helicobacter pylori (Hp)-associated gastritis by simulating Hp infection in gastric mucosal epithelium in vitro. Methods C57BL/6 mice were randomly divided into four groups:control group, model group, PPS (250 mg·kg^-1) group, and positive control group:pyrrolidinedithiocarbamate ammonium (PDTC, 100 mg·kg^-1, the inhibitor of NF- κB pathway). Except for control group, other groups were ig given SS1 solution (1×10⁹ CFU·mL^-1), 0.4 mL for the first day, and 0.2 mL for each time, once a day for consecutive 3 days. Four weeks after ig Hp, PPS group and PDTC group were given corresponding doses of drugs, control group and model group mice given a sterile water, each only 0.4 mL, once a day for 14 d. The stomach was removed, cut along the greater curvature of the stomach, and the changes of gastric mucosa were observed by naked eye. After successful modeling, the gastric mucosa tissues of mice were collected and HE staining was performed to observe the inflammatory infiltration status of gastric mucosa tissues of mice. The colonization of Hp in gastric mucosa of mice was verified by Giemsa staining. The expression of NF-κB was detected by immunohistochemistry (IHC). The expression of inflammatory factor interleukin-8 (IL-8) protein in gastric glands of mice was detected by Western blotting. At the same time, Elisa was used to detect the expression of IL-8 in serum of mice. Results Compared with model group, the gastric mucosa of PPS group was folded neatly, hemorrhagic points disappeared, the gastric mucosa was smooth, and the gastric mucosa was ruddy and shiny. Inflammatory cells infiltration and other tissue damage of PPS group decreased significantly compared with model group. The number of bacterial colonization of PPS group decreased significantly compared with model group. The expression of NF- κB p65 of PPS group was decreased in gastric epithelial cells compared with model group. The expression level of IL-8 protein in gastric glandular tissue of PPS group was significantly decreased compared with model group (P<0.001). Serum IL-8 expression was significantly decreased of PPS group in mice compared with model group (P<0.001). Conclusion PPS may inhibit the expression of inflammatory signal pathway NF-κBrelated molecules plays a protective role in Hp related gastritis.

R285.5

國家自然科學基金項目(81971533);江蘇省中醫(yī)藥局科技項目(YB2015166)