Urinary tract infections (UTI) are often caused by resistant uropathogenic bacteria and can lead to sepsis or chronic renal failure. Cold plasma activated liquid (PAL) has known antimicrobial properties with applications in wound disinfection. The aim of our study is to evaluate PAL as a potential treatment of UTI in an animal model. Based on in vitro tests using a uropathogenic E. coli strain, PAL generated in the atmospheric air Glow Discharge plasma had the strongest antimicrobial effect in comparison to other types of PAL and was further tested in vivo. Transurethral PAL application had no effect on bacterial load in the 24 h mouse model of UTI. Upon investigating the treatment failure, we found that urine completely prevented any antimicrobial effects of PAL and PAL treatment of neutrophils resulted in their reduced viability and loss of mitochondrial membrane potential. These results do not support the hypothesis that the in vitro antimicrobial effects of PAL can be translated to the in vivo model of UTI. This could be explained by the attenuating effect of urine on the antimicrobial activity of PAL and its toxicity on immune cells. The detailed mechanism of the effects of urine on PAL requires further investigation.

尿路感染 (UTI) 通常由耐药性尿路致病菌引起，可导致败血症或慢性肾功能衰竭。冷等离子体活化液体 (PAL) 具有已知的抗菌特性，可用于伤口消毒。我们研究的目的是在动物模型中评估 PAL 作为 UTI 的潜在治疗方法。基于使用尿路致病性大肠杆菌的体外测试 菌株中，大气辉光放电等离子体中产生的 PAL 与其他类型的 PAL 相比具有最强的抗菌作用，并在体内进行了进一步测试。经尿道 PAL 应用对 24 小时 UTI 小鼠模型中的细菌负荷没有影响。在调查治疗失败后，我们发现尿液完全阻止了 PAL 的任何抗菌作用，而 PAL 治疗中性粒细胞导致它们的活力降低和线粒体膜电位丧失。这些结果不支持 PAL 的体外抗菌作用可以转化为 UTI 的体内模型的假设。这可以通过尿液对 PAL 抗菌活性的减弱作用及其对免疫细胞的毒性来解释。尿液对 PAL 影响的详细机制需要进一步研究。