Inhibitory Effects Of Polyphyllin ? On Biofilms Of Candida Albicans

C.albicansis is one of the conditional pathogenic fungi that cause severe nosocomial infection.However,the biofilm formed by C.albicans,because of its ability to increase its drug resistance and protect it from the attack of host immune system,At present,antibiotics such as Amphotericin B are the main drugs for the treatment of C.albicans infection.Because these drugs have some toxic side effects,long-term use can increase kidney damage.Therefore,the effective,low-toxicity clinical drugs for the treatment of C.albicans infection are obtained.Things are the focus of current research.Paris L is a traditional Chinese medicine,the research results have indicated that Paris saponins have many pharmacological effects,such as anti-tumor and anti fungal effect.But at present about polyphyllins on C.albicans formation was less inhibition of membrane biological research,research on its mechanism have not been reported.In view of Polyphyllin ? is one of the main effective components of Polyphyllin,this paper takes Polyphyllin ? as experimental materials,systematically studied the C.albicans biofilm form The results are as follows:?1?The inhibitory effect of Polyphyllin ? on C.albicans was determined by microdilution method.The results showed that Polyphyllin ? had significant inhibitory effect on free C.albicans,its minimum inhibitory concentration of C.albicans?MIC80?and minimal bactericidal concentration?MFCs?were both 8?g/mL.?2?The effects of Polyphyllin ? on the thickness and cell activity of C.albicans biofilm were examined by confocal laser microscopy.The results showed that Polyphyllin ? could decrease the thickness and cell activity of C.albicans biofilm in a dose-dependent manner,that is,the thinner the thickness of the biofilm formed by C.albicans was,the lower the cell activity was 16?g/mL of Polyphyllin ?,compared with the control group,could make C.albicans.The thickness of the biofilm decreased from 53?m in the control group to18?m,and the cell activity decreased 80%.?3?The inhibitory effect of Polyphyllin ? on the mature biofilm of C.albicans was determined by microdilution method.The results showed that Polyphyllin ? also inhibited the mature biofilm of C.albicans significantly.The inhibition of MIC₈₀ and MFC on C.albicans matured biofilm were both 16?g/mL.?4?The effect of Polyphyllin ? on the adhesion of C.albicans was determined by MTT method.The results showed that Polyphyllin ? could inhibit the adhesion of C.albicans in a dose-dependent manner.Compared with the control group,64?g/mL Polyphyllin ? decreased the adhesion rate of C.albicans cells?P<0.01?,indicating that Polyphyllin ? could inhibit the formation of biofilm by inhibiting the adhesion of C.albicans.?5?The inhibitory effect of Polyphyllin ? on C.albicans adhesion at different time was observed by MTT method and inverted microscope.The results showed that the shorter the adhesion time of C.albicans was,the better the inhibitory effect of Polyphyllin ? was.The inhibition rates of C.albicans for 2 h and 4 h after adhesion were 82%and 77%respectively?P<0.01?.The inhibitory effect of C.albicans biofilm was related to the time of adhesion.?6?The effect of Polyphyllin ? on the surface hydrophobicity of C.albicans cells was determined by hydrocarbon assay.The results showed that Polyphyllin ? with subinhibitory concentration could significantly decrease the Polyphyllin ? of C.albicans,including 6?g/mL Polyphyllin ? for 48 h.The relative hydrophobicity of C.albicans cells was decreased from 0.7 in the control group to 0.2?P<0.05?.The results showed that Polyphyllin ? could inhibit the adhesion of C.albicans by decreasing the CSH of C.albicans.?7?The effect of Polyphyllin ? on the transformation of C.albicans from yeast to hyphae was observed by inverted microscope.The results showed that Polyphyllin ? at different concentrations could inhibit the transformation of C.albicans from yeast to hyphae,and 8?g/mL Polyphyllin ? could completely inhibit the formation of C.albicans mycelia.?8?The effect of Polyphyllin ? on the adhesion gene and hypha forming gene of C.albicans was detected by RT-PCR method.The results showed that Polyphyllin ? could significantly reduce the expression level of genes related to the formation of C.albicans biofilm in a dose-dependent manner.Compared with the control group,the inhibition rates of8?g/mL Polyphyllin ? on the adhesion genes HWP1,ALS3 and ECE1 were 42%?85%?76.2%respectively?P<0.01?.The inhibitory rates of EFG1 and CPH1 on hyphal formation genes were 81%and 39%respectively?P<0.01?.It is indicated that Polyphyllin ? can inhibit the C.albicans formation of the expression of its adhesion genes and hyphal formation genes.?9?The effect of polyphyllin ? on the growth of C.albicans hyphae was observed by inverted microscope.The results showed that Polyphyllin ? could inhibit the hyphal growth of C.albicans without adding dbcAMP,but the growth of C.albicans could not be inhibited by the addition of dbcAMP.There was no significant difference between the control group and the control group.It is deduced that Polyphyllin ? is mainly by blocking cAMP signaling pathway inhibits the transformation of C.albicans from yeast to hyphae and thus prevents the formation of C.albicans biofilm.