中药川贝对哮喘模型小鼠气道炎症的影响及可能机制研究

Effect of Bulbus Fritillariae Cirrhosae on airway inflammation in mouse model of asthma

摘要:

目的 观察中药川贝对哮喘模型小鼠气道炎症及白细胞介素8（IL-8）、白细胞介素13（IL-13），趋化因子受体CXCR-2 和趋化因子配体[ 肿瘤生长相关因子-α（GRO-α）、上皮细胞嗜中性粒细胞活性蛋白-78（ENA-78）及嗜中性活性肽-2（NAP-2）] 的影响。方法 BALB/c 小鼠，随机分为正常组、模型组、高剂量组、低剂量组。采用卵蛋白（OVA）致敏激发复制小鼠哮喘模型。造模成功后高剂量组和低剂量组分别按18.0 和9.0 mg/kg 剂量给予中药川贝灌胃；正常组和模型组等量生理盐水灌胃，每天1 次，连续28 d。观察各组小鼠支气管肺泡灌洗液（BALF）中白细胞分类计数的变化；光镜下观察病理学变化并进行炎症评分；ELISA 检测血清中IL-8 和IL-13 浓度；免疫组织化学法检测CXCR-2 和GRO-α、ENA-78、NAP-2 阳性细胞；实时PCR（real-time PCR）检测CXCR-2 和GRO-α、ENA-78、NAP-2 mRNA 的表达。结果 模型组小鼠BALF 中中性粒细胞、巨噬细胞、淋巴细胞和嗜酸性粒细胞计数及炎症评分较正常组增高，差异有统计学意义（P <0.05），高剂量组和低剂量组则较模型组降低，差异有统计学意义（P <0.05）；模型组小鼠IL-8 和IL-13 浓度较正常组增高，差异有统计学意义（P <0.05），高剂量组和低剂量组则较模型组降低，差异有统计学意义（P <0.05）；模型组小鼠CXCR-2 和GRO-α、ENA-78、NAP-2 阳性细胞和mRNA 表达水平较正常组增加，差异有统计学意义（P <0.05），而高剂量组和低剂量组则较模型组降低，差异有统计学意义（P <0.05）。结论 中药川贝可能通过抑制IL-8、IL-13，CXCR-2 和GRO-α、ENA-78、NAP-2 发挥对哮喘模型小鼠的抗炎作用。

Abstract:

Objective To investigate the effect of Bulbus Fritillariae Cirrhosae (BFC) on airway inflammation in mouse model of asthma and potential mechanism. Methods BALB/C mice were randomly divided into normal group, model group, high dose group and low dose group. Mice were challenged with ovalbumin (OVA) to establish asthma model. BFC was orally administered at the dose of 18.0 mg/kg (high dose) and 9.0 mg/kg (low dose) while animals in normal group and model group were orally administered with normal saline. All drugs were administered for consecutive 28 days on a daily basis. Leukocyte counts in bronchoalveolar lavage fluid (BALF) were identified.Morphological abnormality and grading of tissue inflammation were determined. Concentration of IL-8 and IL-13 in serum was measured by Enzyme linked immunosorbent assay (ELISA). Expressions of CXCR-2, GRO-α,ENA-78 and NAP-2 positive cells were detected by Immunochemistry. Levels of CXCR-2, GRO-α, ENA-78 and NAP-2 mRNA were quantified by Real-time PCR. Results Neutrophils, macrophage, monocyte and eosinophils in BALF and inflammation score in model group increased significantly when compared with normal group(P < 0.05), which were attenuated by BFC treatment (high dose and low dose) (P < 0.05). Levels of IL-8 and IL-13 enhanced significantly in model group when compared with normal group (P < 0.05), which was ameliorated by BFC (P < 0.05). Expressions of CXCR-2, GRO-α, ENA-78, and NAP-2 were increased significantly in model group (P < 0.05) when compared with normal group, which was decreased by BFC (P < 0.05). Conclusion BFC exerts anti-inflammatory effect in asthmatic mice through deduction of IL-8, IL-13, CXCR-2 and GRO-α, ENA-78 and NAP-2.