黄连素逆转Hp耐药与外排泵基因调控的相关性研究

Antibiotics resistance is the main reason for the failure of eradication of Helicobacter pylori. The combination of the overexpression of efflux pump and gene mutations can lead to antibiotic resistance of Hp. Studies have confirmed that berberine can inhibit Hp resistance，but the relationship with the expression of efflux pump genes is still unclear. Our study will collect endoscopy specimens, isolate H.pylori, screen the single and multiple drug-resistant strains by classical drug sensitive test. The research plans to detect minimal inhibitory concentration (MIC) of berberine on Hp resistant strains and explore its impact on antibiotics sensitivity. Our work attempts to compare the influence of berberine on efflux pump TolC homologous genes expression in gene level. We will establish Hp-infected BALB/c mice model, verify the outside efflux function of berberine on various antibiotics in the gastric mucosa by high-performance liquid chromatography (HPLC) and analyze the correlation between the berberine-induced drug sensitivity changes and expression differences of efflux pump TolC homologous genes. The aim is to explore the regulation of efflux pump TolC homologous genes in berberine reversing antibiotics resistance of Hp and support clinical medication for eradication Hp infection.

抗生素耐药是幽门螺杆菌（Helicobacter pylori ,Hp）根除治疗失败的主要原因，Hp外排泵的过量表达及基因突变可共同导致细菌耐药。已有研究证实黄连素可抑制Hp耐药，但其对耐药性的抑制与外排泵基因表达的关系尚未明确。本研究通过分离培养胃粘膜中Hp，采用经典的药敏试验筛选单一耐药和多重耐药株，测定黄连素对各耐药株的MIC值，验证黄连素处理后对耐药菌株的各抗生素敏感性的影响；基因水平比较黄连素处理后对外排泵TolC同源基因表达的影响；建立Hp感染的BALB/c小鼠模型模拟体内代谢，高效液相色谱法验证黄连素对胃粘膜中各种抗生素的外排抑制作用，分析黄连素引起药物敏感性变化与外排泵TolC同源基因表达差异的相关性。明确黄连素逆转Hp耐药与外排泵TolC同源基因调控的相关性，为提高Hp根除率提供理论依据。

抗生素耐药是幽门螺杆菌（Helicobacter pylori,Hp）根除治疗失败的主要原因，Hp外排泵的过量表达及基因突变可共同导致细菌耐药。已有研究证实黄连素可抑制Hp耐药，但其对Hp耐药性的抑制与外排泵基因表达的关系尚未明确。本研究通过分离培养胃粘膜中Hp，采用经典的药敏试验筛选或体外诱导出多重耐药菌株，测定黄连素对各耐药株的MIC值，验证黄连素处理后对多重耐药菌株的各抗生素敏感性的影响；基因水平比较黄连素处理后对外排泵基因表达及靶基因突变的影响，分析黄连素引起药物敏感性变化与外排泵基因表达差异及对应靶基因突变的相关性。研究结果表明外排泵基因Hp0605、Hp0606、Hp1328表达量的升高与耐药基因突变共同导致了Hp的多重耐药，黄连素可通过下调部分外排泵基因的表达量而降低多重耐药菌株对3种抗生素(克拉霉素、左氧氟沙星、甲硝唑)的耐药性，且逆转程度不一。为中医药应用于Hp的个体化根除治疗、逆转Hp耐药提供理论依据。