中药清燥润肺化浊行血汤对PM2．5致肺损伤小鼠的干预作用

Intervention effect of Qingzao Runfei Huazhuo Xingxue decoction on PM2.5-induced pulmonary injury in mice

目的观察中药清燥润肺化浊行血汤对PM2．5致肺损伤小鼠炎症反应及组织病理学的影响，探讨中药防治雾霾致肺损伤的可能机制。方法选择50只健康清洁级雄性C57BL／6小鼠，按随机数字表法分为对照组、模型组和低、中、高剂量清燥润肺化浊行血汤干预组5组，每组10只。采用经鼻腔滴注PM2．5悬液40mg／kg的方法建立PM2．5致肺损伤小鼠模型，对照组滴注等量生理盐水。低、中、高剂量清燥润肺化浊行血汤干预组于制模后次日灌胃15、25、50mL·kg^-1·d^-1清燥润肺化浊行血汤（组成：鸭梨75g、川贝母10g、百部8g、半夏8g、桔梗6g、紫苑10g、杏仁5g、百合6g、红景天4g、荷叶3g、路路通6g、赤芍5g、决明子6g），共21d；对照组和模型组给予等量生理盐水。于干预21d后处死小鼠，取左侧肺脏进行支气管肺泡灌洗，收集支气管肺泡灌洗液（BALF），测定BALF中酸性磷酸酶（ACP）、碱性磷酸酶（AKP）、乳酸脱氢酶（LDH）及白蛋白（ALB）的含量；取右侧肺组织，苏木素-伊红（HE）染色后光镜下观察肺组织病理学改变。结果经鼻腔滴注PM2．5悬液后，模型组BALF中ACP、AKP、LDH、ALB均较对照组明显升高[ACP（U／L）：3．9±0．4比1．7±0．3．AKP（U／L）：9．0±1．5比4．8±0．3，LDH（U／L）：416．7±44．4比112．5±20．3，ALB（mg／L）：198．7±32．4比65．8±21．3，均P〈0．05]；光镜下显示，肺组织可见PM2．5颗粒聚积，肺泡间隔明显增厚，肺泡腔及肺间质炎性细胞浸润明显。经清燥润肺化浊行血汤干预后，BALF中生化指标明显改善，并呈剂量依赖性，高剂量清燥润肺化浊行血汤干预组各项指标明显低于模型组[ACP（U／L）：2．1±0．8比3．9±0．4，AKP（U／L）：5．3±1．4比9．0±1．5，LDH（U／L）：146．6±29．8比416．7±44．4，ALB（mg／L）：88．5±26．7比198．7±32．4，均P〈0．05]；光镜下显示，肺组织病理学改变随干预剂量增加逐渐减轻。结论清燥润肺化浊行血汤能减轻PM2．5引起的肺部炎症反应及组织损伤，且呈一定量效关系，其机制可能与其调节炎性介质免疫应答有关，为中药治疗PM2．5致肺损伤提供了依据。

Objective To study the effects of Qingzao Runfei Huazhuo Xingxue decoction （QRHXD） on inflammatory reaction and histopathology in mice with PM2.5-induced pulmonary injury, and to approach the possible mechanism of prevention and treatment of traditional Chinese medicine on lung injury induced by haze. Methods Fifty healthy male C57BL/6 mice were randomly divided into five groups （n = 10）： namely control, PM2.5, PM2.5 ＋ low-, moderate-, and high-dose groups. The PM2.5 suspensions at a dosage of 40 mg/kg was respectively given to mice by the nasal instillation for reproduction of mouse model of lung injury induced by PM2.5, and the mice in control group were given the same volume of normal saline. The mice in PM2.5 ＋ low-, moderate-, and high-dose QRHXD groups were given 15, 25, 50 mL· kg^-1· d^-1 QRHXD by oral perfusion daily for consecutive 21 days at the next day of model reproduction （the QRHXD included： Pear 75 g, Bulbus Fritillariae Cirrhosae 10 g, Radix Stemonae 8 g, Rhizoma Pinelliae 8 g, Radix Platycodi 6 g, Aster 10 g, Almond 5 g, Lily 6 g, Rhodiola 4 g, Lotus 3 g, Fructrs Liquidambaris 6 g, Radix Paeoniae Rubra 5 g, Semen Cassiae 6 g）. The mice in control and PM2.5 groups were given equivalent volume of normal saline respectively. After treatment for 21 days, the mice were sacrificed, and the left lung was harvested for bronchoalveolar lavage, and the bronehoalveolar lavage fluid （BALF） was collected for determination of levels of acid phosphatase （ACP）, alkaline phosphatase （AKP）, lactic dehydrogenase （LDH）, and albumin （ALB）. The right lung was harvested for histopathology observation under light microscope using hematoxylin and cosine （HE） staining. Results After intranasal instillation of PM2.5 suspension, the levels of ACP, AKP, LDH, and ALB in PM2.5 group were significantly higher than those in control group [ACP （U/L）： 3.9 ± 0.4 vs. 1.7 ±0.3, AKP （U/L）： 9.0±1.5 vs. 4.8±0.3, LDH （U/L）： 416.7±44.4 vs. 112.5±20.3, ALB （mg/L）： 198.7＋32.4 vs. 65.8±21.3, all P 〈 0.05]. Under light microscope, the PM2.5 particles were collected, the alveolar septa were thickened, and the inflammatory cells in the alveolar cavity and pulmonary interstitium were found. On the contrary, after administration of QRHXD, a significant reduction of biochemical indexes was found, which showed a dose-dependent manner. The parameters of PM2.5 ＋ high-dose QRHXD group were significantly lower than those in PM2.5 group [ACP （U/L）： 2.1 ±0.8 vs. 3.9 ±0.4, AKP （U/L）： 5.3± 1.4 vs. 9.0 ± 1.5, LDH （U/L）： 146.6±29.8 vs. 416.7 ±44.4, ALB （mg/L）： 88.5 ±26.7 vs. 198.7 ± 32.4, all P 〈 0.05]. At the same time, the pathological changes in hmg tissue were better with the increase of the dose. Conclusions QRHXD can reduce the pulmonary inflammatory response and tissue damage caused by PM2.5, with the increase concentration of Chinese medicine, and the effect is more obvious. This may be related to the immune response of the human body to regulale inflammatory mediators, which provide basis for the treatment of pulmonary injury induced by PM2.5.