壳聚糖抑制高糖诱导的脂质过氧化及血管内皮细胞与单核细胞黏附

Chitosan inhibits high glucose-induced peroxidation and monocytes adhesion to vascular endothelial cells

目的研究壳聚糖(chitosan)对高糖诱导细胞产生脂质过氧化及血管内皮细胞与单核细胞黏附的抑制作用。方法建立人脐静脉血管内皮细胞(HUVEC)高糖培养模型,实验分空白对照组、高糖模型组、高糖+壳聚糖组,测定细胞产生羟自由基(OH.)及脂质过氧化产物丙二醛(MDA)量;同时取单核巨噬细胞系Raw264.7,以荧光染料Rhodamin123孵育后加入以上各组,荧光摄像及比色检测单核细胞黏附数量;RT-PCR法检测血管细胞黏附分子(VCAM-1)mRNA变化。结果与空白对照组比较,高糖引起HUVEC产生OH.及MDA含量增加,黏附于HUVEC的Raw264.7数量以及VCAM-1表达升高;壳聚糖可呈浓度依赖性地抑制上述现象,但对细胞存活无明显影响。结论壳聚糖可能通过减轻自由基与脂质过氧化损伤,下调血管内皮细胞VCAM-1的表达,从而抑制高糖诱导的单核细胞与内皮细胞黏附。

Aim To study the inhibitory effect of chitosan on peroxidation and monocytes adhesion to vascular endothelial cells induced by high concentration of glucose. Methods Human umbilical vascular endothelial cells （HUVEC） were treated with high glucose, and high glucose with different concentrations of chitosan for 24 h. Hydroxyl radicals （OH·） and malondialdehyde （MDA） were measured. Monocytes Raw 264.7 were pre-incubated with Rhodamin123, and then co-cultured with HUVEC for 30 min, followed bymicroscope observation and determination of the monocytes adhesion. Finally, the mRNA expression of vascular cell adhesion molecular-1 （VCAM-1） was evaluated by reverse transcription polymerase chain reaction （RT-PCR）. Results Concentrations of OH· and MDA in HUVEC increased after incubation with high glucose. Both of the amount of adhesive monocytes and mRNA expression level of VCAM-1 in HUVEC were induced by high glucose. Inversely, chitosan inhibited these changes in a dose-dependent manner without any cytotoxicity to cells. Conclusion Chitosan can scavenge free radicals and prevent peroxidative injury on vascular endothelial cells, which further down-regulates the expression of VCAM-1 and consequently inhibits the adhesion of monocytes to endothlial cells.