小檗碱对DNFB诱导的小鼠迟发型超敏反应的影响

目的:研究小檗碱(Ber)对二硝基氟苯(DNFB)诱导的小鼠迟发型超敏反应(DTH)的影响,探讨其免疫抑制作用的机制。方法:BALB/c小鼠分为对照组、DTH组与Ber处理的DTH组。对照组以不含DNFB的溶剂处理,DTH组以5g/LDNFB腹部致敏、耳廓激发的方法建立模型,Ber处理的DTH组每天腹腔注射(i.p)Ber,连续7d,总剂量为30mg/kg体质量。激发后48h,取小鼠双耳称重了解Ber对炎症抑制率的影响。镜下观察耳廓局部组织的变化;以结晶紫法检查Ber对脾脏T淋巴细胞与细胞外基质(ECM)黏附作用的影响;以膜联蛋白V(AnnexinV)染色检查淋巴结细胞的凋亡率。结果:双耳称重的结果显示,Ber处理的DTH组与DTH组具有显著的差异(P<0.05),能明显抑制DNFB引起的炎症反应;耳廓局部组织学检测也表明,Ber能够抑制DNFB诱导的DTH,明显减少淋巴细胞的浸润。Ber处理的DTH组的T细胞与ECM的黏附能力明显降低(P<0.05)。Ber处理的DTH组与DTH组和对照组的细胞凋亡率均无明显差异(P>0.05)。结论:Ber对DNFB诱导的小鼠DTH具有明显的抑制作用,降低小鼠T细胞与ECM的黏附能力可能是其抑制DTH的机制之一。

Effects of berberine on DNFB-induced delayed type hypersensitivity in mice

AIM: To investigate the effect of berberine (Ber) on DNFB-induced delayed type hypersensitivity (DTH) and explore the mechanism of the immunosuppression effect of berberine. METHODS: BALB/c mice were divided into three groups: control group, DTH group, and Ber-treated DTH group. The DTH group was sensitized to DNFB by painting the shaved abdomen with DNFB dissolved in propanone/olive oil. The Ber-treated DTH group was injected (i.p.) with berberine daily for 7 consecutive days, with the total dose of 30 mg/kg. The control group was treated with the solvent without DNFB. All mice were then challenged by painting 10 microL of 2 g/L DNFB on the left ears. The weight of right and left ears was measured at 48 h after challenge. Histological changes of mouse auricles were observed under light microscopy. Violet crystal staining was used to determine the effect of Ber on adhesion of mouse splenic lymphocytes to extracellular matrix (ECM). Annexin-V staining was used to detect the apoptotic rate of the lymphocytes in the lymph nodes. RESULTS: The results of ear weighting showed that Ber significantly inhibited DTH reaction (P<0.05). Histological observation indicated Ber reduced markedly the infiltration of lymphocytes. The adhesion of T lymphocytes to ECM was also notably decreased by Ber treatment (P<0.05). There was no obvious difference in apoptotic rates of the lymphocytes among Ber-treated DTH group, DTH group and control group (P>0.05). CONCLUSION: Ber can significantly inhibit the DNFB-induced DTH in mice. The reduced adhesion between mouse T lymphocytes and ECM may be one of the mechanisms of suppression of DTH by Ber.