积雪草苷的抗菌作用及对小鼠实验性泌尿系统感染的治疗作用

Suppression of bacterial urinary infection in mice with asiaticoside

目的:研究积雪草苷的体内外抗苗作用。方法:采用平皿二倍稀释法测定积雪草苷对37株标准菌株及临床分离致病菌株的最低抑菌浓度(MIC);采用小鼠膀胱上行性肾感染模型,观察积雪草苷在0．68～3．36 g·kg-1剂量时灌胃给药对大肠埃希菌26的清除作用,用Bliss程序计算药物清除细菌的半数有效剂量(ED50)和95％置信限。结果:积雪草苷对37株标准及临床分离菌株显示较强的抗菌活性,尤其对各种耐药细菌,包括耐甲氧西林的金葡球菌(MRSA)、表葡菌(MRSE),耐5种氨基糖苷类抗生素、产钝化酶的粪肠球菌,产β-内酰胺酶、产超广谱β-内酰胺酶的大肠埃希菌、肺炎克雷伯杆菌和醋酸钙不动杆菌,以及耐哌拉西林的铜绿假单胞菌的MIC值与三金片相近。积雪草苷对小鼠膀胱上行性肾感染大肠埃希菌26的清除细菌作用较强,积雪草苷和三金片的ED50分别为1．87和3．16 g·kg-1(P<0．01)。结论:积雪草苷具有良好的体内、外抗菌活性,尤其对于泌尿系统感染。

Objective：To study the antibacterial activities of asiaticoside. Methods：The minimum inhibition concentration（MIC）with asiaticoside was measured by a two-fold dilution assay with 37 strains of standard and clinically isolated pathogenic bacteria. A model of mouse bladder ascending kidney infection by Escherichia coli 26 was used to evaluate in vivo antibacterial activities of asiaticoside at dosage range of 0.68 - 3.36 g· kg^-1. Sanjin tablets were used as positive control. The EDs0 values of bacterial eradication with CI 95% were calculated using a Bliss programming. Results： Asiaticoside suppressed 37 strains of standard and clinical pathogenic bacteria, showing more potent inhibition over several antibiotic-resistant bacterial strains, such as methicillin-resistant S. aureus （MRSA）and S. epidermidis （MRSE） , aminoglycoside antibiotics-resistant E. faecalis, ESBL-producing E. coli, K. pneumoniae, A. calcoaceticus and piperacillin-resistant P. aeruginosa. The MICs of asiaticoside were equivalent to that of Sanjin tablets. Asiaticoside showed potent bacterial eradication in mice with bladder ascending kidney infection. The ED50 of asiaticoside and Sanjin tablets was 1.87 g·kg^-1 versus 3. 16 g ·kg^-1 （p 〈 0.01 ）. Conclusion：Asiaticoside showed antibacterial activities both in vitro and in vivo. Its therapeutic efficacy on urinary infection is worthy of further investigation.