摘要
目的观察姜黄素介导的光动力疗法(PDT)对耐甲氧西林金黄色葡萄球菌(MRSA)及其生物膜活性的影响。方法先用单态氧荧光探针(SOSG)验证光动力下姜黄素产生活性氧(ROS);后实验对象为MRSA悬液和MRSA生物膜,均分为姜黄素组、PDT组、姜黄素-PDT组、空白对照组4组。姜黄素组和姜黄素-PDT组分别设置不同浓度剂量组(1.00、6.25、12.50、25.00μmol/L)。PDT处理为450nm波长光源照射(辐照度1W/cm^2)。稀释平板法检测MRSA浮游菌存活率,MTT法测定生物膜内MRSA存活率。MRSA生物膜通过扫描电镜观察鉴定。应用SPSS20.0统计软件分析,计量资料以均值±标准差(Mean±SD)表示,各组间比较用方差分析。组间差异有统计学意义时进行组间两两比较的SNK-q检验。结果姜黄素光动力下产生ROS呈浓度依赖性;浓度一定时,ROS量5min后趋于稳定。实验浓度范围内,姜黄素-PDT组对MRSA浮游菌及生物膜内细菌的杀伤作用呈姜黄素浓度依赖性,浓度为25μmol/L时,存活率分别降至(0.38±0.32)%、(34.50±1.44)%,同时,扫描电镜结果显示生物膜完整性破坏明显。姜黄素组、PDT组与空白对照组比较,差异无统计学意义(t=0.28、0.71,P>0.05)。结论姜黄素介导PDT体外对MRSA浮游菌及生物膜内MRSA均有浓度依赖性的杀伤作用,同时还可有效破坏MRSA生物膜结构。
Objective To examine the effect of curcumin-mediated photodynamic therapy (PDT) on Methicillin-resistant Staphylococcus aureus (MRSA) and its biofilm structure. Methods Singlet oxygen sensor green reagent (SOSG) was used to test reactive oxygen species (ROS) generation induced by curcumin-PDT. Both bacterial suspension and MRSA biofilm were divided into 4 groups respectively: Curcumin group, PDT group, Curcumin-PDT group and the Control group. The concentration of curcumin in curcumin group and irradiation group was 1.00, 6.25, 12.50, 25.00 μmol/L. PDT is treated as a 450 nm wavelength light source (irradiance 1 W/cm squared). The survival rates of MRSA planktonic bacteria were calculated with Diluted plate. Survival rates of bacteria within biofilm structure were measured with tetrazolium salt colorimetry (MTT) assay. Microscope was used to observe and identify the changes of the structure of MRSA biofilm. Results The production of ROS induced by curcumin-PDT was increased in a concentration-dependent manner. ROS expression tended to be stable after 5 min within same curcumin concentration. The killing effect of curcumin-PDT on MRSA planktonic bacteria and bacteria inside the biofilm culture was occurred in a concentration-dependent manner, and the survival rate was decreased to (0.38±0.32)% and (34.50±1.44)% respectively with 25 μmol/L curcumin treatment. Meanwhile, scanning electron microscope results showed that the biofilm integrity was disrupted seriously in the curcumin-PDT group. There were no obvious differences between Curcumin group, PDT group and the Control group (t=0.28, 0.71, P>0.05). Conclusion Our study showed that curcumin-PDT not only has a killing effect on MRSA planktonic bacteria and the bacteria inside the biofilm culture in a concentration-dependent manner but also destroy the structure of biofilm.
作者
丁涛
高鹰
孙康
王远贺
刘江俊
田少奇
Ding Tao;Gao Ying;Sun Kang;Wang Yuanhe;Liu Jiangjun;Tian Shaoqi(Department of Articular Surgery,the Affiliated Hospital of Qingdao University,Qingdao 266555,China;Department of Orthopedics,Laizhou People’s Hospital,Laizhou 261400,China)
出处
《中华实验外科杂志》
CAS
CSCD
北大核心
2019年第6期1092-1094,共3页
Chinese Journal of Experimental Surgery
基金
国家自然科学基金青年基金(81702172).
