The Treatment Effects Of Verbascoside On Clostridium Perfringens Gas Gangrene

Clostridium perfringens,known as Clostridium weisserii,is widely present in nature.It is a regular intestinal flora found in humans and animals.It is a conditional pathogen and divided into five serotypes of AE according to the exotoxin secreted from it.Clostridium perfringens type A could induce food poisoning and a variety of diseases such as gas gangrene,among which gas gangrene is presented in multiple types of animals.In the case of deep injury or inadequate postoperative care,patients generally get infected by pathogens and induced gangrene,which possess a short incubation period.The infection it will merely take 48 hours from episoede to death.Therefore,once the early golden treatment period of infection is passed up,it often induces to death because of the infection.In addition,if the treatment is not performed on time and effectively,it will also threaten public health and induce to severe economic losses.Clostridium gas gangrene is an outbreak of infectious disease,which is mainly caused by alpha toxin and theta toxin secreted by Clostridium perfringens.Alpha toxin(C.perfringens alpha toxin or Phospholipase C,CPA or PLC)which belongs to the bacterial zinc-metal phospholipase family,is one of the main toxins of Clostridium perfringens,and possesses both phospholipase C and sphingomyelinase activities.It is the crucial toxin induced to gangrene gas.Theta toxin,known as PFO,is a member of the pore-forming cholesterol-dependent cytolysin family.It could be associated with alpha toxins to induce neutrophils injuries aggregated at the site of infection,endothelial cells dysfunction,and subsequently offers a anaerobic environment to airborne capsules.In this study,two toxins that cause clostridial gas gangrene were used as research targets.An inhibitor screening platform was established through hemolysis experiments.Finally,potential virulence factor inhibitors were screened out from traditional Chinese medicine compounds and their mechanism of action was determined.It expounded to provide new solutions and theoretical basis for exploring new treatment methods of Clostridium gas gangrene.In this study,through various test methods such as hemolysis test,growth curve and MIC test,the natural compound molecule verbascoside was screened in a concentration range that does not affect the normal growth of Clostridium perfringens(2-32 ?g / ml)could effectively inhibit the hemolytic activity of CPA and PFO.In vitro cell tests and rats infection model tests implied that Verbascoside performes a very good protective effect on Caco-2 cells damaged by CPA or PFO invasion.Meanwhile,it reduces the mortality of gas gangrene rats.Molecular dynamics simulation and site-specific residue mutation test results showed that Verbascoside inhibits two toxins activities by combining with PFO and CPA.The main residues which bind to PFO are ASN199,SER55 and ASN197,while the main residues that bind to CPA are ALA89 and TYR90.In summary,this study showed that Verbascoside could effectively inhibit the Hemolytic activities of CPA and PFO,and reduce the bacterial pathogenicity.It is a potential lead compound for the treatment of gas gangrene and provides a certain theory basis for the gas gangrene therapy..