基于Nrf2/HO-1信号通路探讨艾灸改善Hp胃黏膜炎性损伤的作用机制

Helicobacter pylori (Hp) is closely related to the patients with chronic gastritis.It is the main way of the treatment for this kind of disease to improve gastric mucosa inflammatory damage by Hp infection, and thus it become a research hotspot in recent years.It is show that moxibustion protect gastric mucosa by inhibiting the expression of inflammatory cytokines during the early stage of the basic experiment. But it is unclear of the inner mechanism how moxibustion inhibit inflammatory cell damage.Nrf2/HO-1 signaling pathway is closely related to inflammatory lesions, the activation of which can inhibit oxidative stress injuries, and reduce the inflammatory damage of tissue.On this basis, We hypothesized that moxibustion improve inflammatory injury of gastric mucosa by activating this signal pathway, in order to reveal the mechanism of moxibustion protecting gastric mucosa.Base on the mice model of Hp gastric mucosal damage by Nrf2(-/-) transgenic mice, this study discusses the regulation of moxibustion for Hp gastric mucosa of the occurrence of apoptosis and inflammatory factor expression,whether the blocking of Nrf2/HO-1 signaling pathway.This study will deepen the understanding of the mechanism of therapy of chronic gastritis by moxibustion, which providing new theoretical basis for prevention and control of chronic gastritis for application of moxibustion.

幽门螺杆菌（Hp）与慢性胃炎的发病有着密切的联系。改善Hp致胃黏膜炎性损伤是治疗这类疾病的主要途径，因而成为近年来研究的热点。前期基础实验发现艾灸通过抑制炎性因子的表达而发挥保护胃黏膜的作用，但艾灸如何抑制细胞炎性损伤内在机制的研究尚不明确。Nrf2/HO-1信号通路与炎症损伤密切相关，该通路的激活可抑制氧化应激损伤的发生，减少组织的炎性损伤。据此，我们提出艾灸改善胃黏膜的炎性损伤可能是通过激活该信号通路而起保护作用，以揭示艾灸保护胃黏膜的作用机制。本课题拟应用Nrf2(-/-) 转基因小鼠建立Hp胃黏膜损伤模型，探讨Nrf2/HO-1信号通路阻断前后，艾灸对Hp胃黏膜细胞凋亡、炎性因子的表达的调控作用。本项目的研究将深化艾灸治疗慢性胃炎机理的认识，为艾灸应用于慢性胃炎的防治提供新的理论依据。

目的：观察艾灸改善Hp胃黏膜炎性损伤，是否通过调控Nrf2/HO-1信号通路.方法：将小鼠随机分成Nrf2+/+小鼠对照组(Nrf2+/+空白组)、Nrf2-/-小鼠对照组(Nrf2-/- 空白组);Nrf2+/+小鼠 Hp 感染模型组(Nrf2+/+模型组)、Nrf2-/-小鼠 Hp 感染模 型组(Nrf2-/-模型组);Nrf2+/+小鼠 Hp 感染模型加艾灸穴位组(Nrf2+/+艾灸组)、 Nrf2-/-小鼠 Hp 感染模型加艾灸穴位组(Nrf2-/-艾灸组);Nrf2+/+小鼠 Hp 感染模 型加艾灸非穴点组(Nrf2+/+艾灸非穴组)、Nrf2-/-小鼠 Hp 感染模型加艾灸非穴 点组(Nrf2-/-艾灸非穴组)，利用病理染色、电镜、Western blot、 RT-PCR、Elisa 等实验技术，分析 Nrf2/HO-1 信号阻断对艾灸干预 Hp 小鼠的炎性损伤的逆转作用。.结果：正常对照组小鼠胃粘膜上皮完整，无明显炎症损伤；模型组小鼠胃粘膜腺体减少、炎症细胞浸润；与模型组比较，艾灸处理组炎性浸润明显缓解，Nrf2-/-模型组的病变增强；与正常对照组比较，Bax表达增加，模型组Bcl-2表达降低；与模型组比较，艾灸处理组Bax表达降低，Bcl-2表达增加。与模型组比较，Nrf2-/-模型组Bax表达增加，Bcl-2表达降低。 与正常对照组比较，模型组小鼠胃粘膜凋亡细胞增加；与模型组比较，艾灸处理组凋亡细胞减少，Nrf2-/-模型组的凋亡细胞增加。免疫荧光显示与正常对照组比较，模型组Nrf2蛋白表达降低；与模型组比较，艾灸处理组Nrf2蛋白表达增加。 ELISA检测,模型组TNF-α、IL-1β、IL-12表达增加，IL-10表达降低；与模型组比较，艾灸处理组TNF-α、IL-1β、IL-12表达降低，IL-10表达增加；与模型组表，Nrf2-/-模型组TNF-α、IL-1β、IL-12表达增加，IL-10表达降低。Western blotting检测及PCR显示，模型组Nrf2、HO-1、NQO1表达降低，NF-κB、TNF-α表达增加；艾灸处理组Nrf2、HO-1、NQO1表达增加，NF-κB、TNF-α表达降低。 .结论：艾灸通过调控Nrf2/HO-1信号通路，从而抑制胃黏膜细胞凋亡及炎性因子的表达，从而达到改善胃黏膜炎性损伤的作用