Anti-biofilm activity of white horehound extract in catheter-associated infection

描述(申请人提供)：金黄色葡萄球菌是所有细菌病原体中最突出的一种。耐药性的持续出现，加上其产生致病因子和生物膜的能力，导致社区和医院的发病率和死亡率不断上升。金黄色葡萄球菌产生的生物膜极难根除，是顽固性感染的令人厌烦的来源。生物被膜增加了对抗菌素治疗的抵抗力，显然有必要开发平房抗生物膜疗法。这项建议的实验重点是评估从白色猎犬中提取的天然产物用于治疗生物被膜相关葡萄球菌感染的潜力。白色猎鹰是一种原产于地中海的野生草本薄荷。它是意大利南部补充和替代医学(CAM)框架内使用的最重要的药用植物之一。特别是，该植物的煎剂用于治疗几种类型的皮肤和软组织感染，其中许多与葡萄球菌感染有关。我已经证实，白藜芦根的粗乙醇提取物在破坏已建立的葡萄球菌生物膜方面表现出显着的活性。该建议的实验部分分为四个目标：1)分离和分离白喉科动物的生物活性化合物；2)在葡萄球菌生物被膜的背景下评估白喉科动物化合物的体外疗效；3)评估活性化合物的体外细胞毒性；以及4)使用导管相关葡萄球菌生物膜感染的小鼠模型评估活性化合物(S)的体内预防和治疗效果。 这些目标将通过生物测定指导的分离技术来实现，其中植物化学方法(机理柱、高效液相色谱和LC/MS)将与体外生物膜模型相结合。活性化合物的细胞毒性将在动物研究开始前进行评估。小鼠模型将被用来评估这些化合物的体内预防能力和治疗效果。我相信，这些实验最终将导致确定用于预防和治疗葡萄球菌导管相关生物被膜感染的新型治疗剂。 公共卫生相关性：金黄色葡萄球菌会导致毁灭性的感染，而目前的抗葡萄球菌药物储备不足。这项建议旨在研究一种受欢迎的植物性传统药物在预防和治疗生物被膜感染方面的潜在治疗应用。

DESCRIPTION (provided by applicant): Staphylococcus aureus is one of the most prominent of all bacterial pathogens. The continued emergence of drug resistance combined with its ability to produce virulence factors and biofilms has lead to increasing morbidity and mortality in both community and hospital settings. Biofilms produced by S. aureus are extremely difficult to eradicate and are the wearisome source of recalcitrant infection. Biofilms confer increased resistance to antimicrobial therapy and there is a clear need for the development of hovel antibiofilm therapies. The experimental focus of this proposal is to assess the potential of natural products extracted from white horehound (Marrubium vulgare L., Lamiaceae) for the treatment of biofilm-associated staphylococcal infection. White horehound is a wild herbaceous mint native to the Mediterranean. It is one of the most important medicinal plants used within the complementary and alternative medicine (CAM) framework of southern Italy. In particular, decoctions of the plant are topically applied for the treatment of several types of skin and soft tissue infection, many of which are related to staphylococcal infection. I have already established that crude ethanolic extracts of white horehound roots demonstrate remarkable activity in the disruption of established staphylococcal biofilms. The experimental component of this proposal is divided into four aims: 1) to fractionate and isolate bioactive compounds from white horehound; 2) to assess the in vitro efficacy of white horehound compounds in the context of staphylococcal biofilms; 3) to assess the in vitro cytotoxicity of active compounds; and 4) to assess the in vivo prophylactic and therapeutic efficacy of active compound(s) using murine models for catheter-associated staphylococcal biofilm infection. These aims will be addressed with bioassay-guided fractionation techniques, in which phytochemical methods (mechanism columns, HPLC, and LC/MS) will be combined with in vitro biofilm models. The cytotoxicity of active compounds will be assessed before the initiation of animal studies. A murine model will be used to assess the prophylactic capacity and therapeutic efficacy of these compounds in vivo. I believe that these experiments will ultimately lead to the identification of novel therapeutic agents for the prevention and treatment of staphylococcal catheter-associated biofilm infection. PUBLIC HEALTH RELEVANCE: Staphylococcus aureus causes devastating infections, and the current repertoire of antistaphylococcal drugs is insufficient. This proposal is aimed at investigating a popular plant-based traditional medicine for potential therapeutic applications in the prevention and treatment of biofilm infection.