高浓度葡萄糖对表皮葡萄球菌生物膜在生物材料表面形成的影响

Effect of high-concentration glucose on biofilm formation of Staphylococcus epidermidis on the surface of biomaterials

背景:因植入性材料所带来的生物材料感染在糖尿病患者中较高,在非糖尿病手术期间存在高血糖的患者也有较高感染率。在体外研究不同浓度血糖对生物材料上形成细菌生物膜的影响报道较少。目的:观察高浓度葡萄糖对表皮葡萄球菌生物膜在生物材料表面形成的影响。方法:采用不同浓度葡萄糖培养表皮葡萄球菌感染模型。结晶紫染色法对生物膜进行半定量检测,激光共聚焦显微镜观察生物膜的厚度。结果与结论:半定量实验显示生物膜形成阳性株(表皮葡萄球菌ATCC35984)吸光度值均大于0.12,随着培养基中葡萄糖浓度的增加,其吸光度值呈上升趋势,而在50mmol/L葡萄糖浓度时其吸光度值最高。激光共聚焦显微镜观察生物膜形成阳性株(表皮葡萄球菌ATCC35984)中,≥11.1mmol/L葡萄糖各组与无葡萄糖组相比,其生物膜厚度明显增加(P<0.05)。生物膜形成最高值在50mmol/L组。生物膜形成阴性株(表皮葡萄球菌ATCC12228)中均无明显生物膜形成。结果表明高浓度葡萄糖明显诱导表皮葡萄球菌生物膜的形成,控制血糖是降低糖尿病生物材料感染的重要措施之一。

BACKGROUND：There are high rates of bacterial infection on the surface of implanted biomaterials in diabetic patients;it is uncertainly high of infection rate in non-diabetic patients with hyperglycemia during the operation.Few studies report the effect of different concentrations of glucose on the bacterial biofilms formed on the surface of biomaterial in vitro.OBJECTIVE：To investigate the effect of high concentration of glucose on the biofilms on the surface of biomaterial in Staphylococcus epidermidis.METHODS：Staphylococcus epidermidis model of biomaterial infection was cultured in different concentrations of glucose.Biofilms mass was semi-quantified by crystal violet dye.The thicknesses of biofilms were measured by confocal laser scanning microscope.RESULTS AND CONCLUSION：Semi-quantitative experiments showed that the absorbance values of biofilm formation positive strains （Staphylococcus epidermidis ATCC35984） was greater than 0.12,with the increasing concentration of glucose in the culture medium,the absorbance values also raised and reached a peak at 50mmoL/L glucose concentration.Confocal laser microscopy demonstrated that,on biofilm formation positive strains （Staphylococcus epidermidis ATCC35984）,the biofilm was significantly thicker in ≥11.1mmoL/L glucose group compared with no glucose group （P0.05）.The maximum value of biofilm formation occurred with 50mmoL/L glucose.There were no biofilms formed in biofilm negative strains （Staphylococcus epidermidis ATCC12228）.High concentration of glucose can induce the formation of biofilms in Staphylococcus epidermidis,controlling glucose is more important to decrease the incidence rate of biomaterial infection in diabetes mellitus.