ABSTRACT
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 bronchoalveolar 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 eosine (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 lung 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 regulate inflammatory mediators, which provide basis for the treatment of pulmonary injury induced by PM2.5.
ABSTRACT
Objective To study the influence of Qingzao Runfei Huazhuo Xingxue decoction on pulmonary tissue and lung function in mouse model of lung injury induced by PM2.5, and to provide an idea of clinical prevention and treatment of respiratory diseases induced by PM2.5. Methods Totally 30 clean level male ICR mice were randomly divided into three groups: normal control group, model group and Qingzao Runfei Huazhuo Xingxue decoction intervention group, with 10 mice in each group. Model of PM2.5-induced respiratory disease in mice was reproduced by instilling nasal cavity drip PM2.5 suspension 40 mg/kg once a day for 6 weeks. In the treatment group, the mice were fed with the Qingzao Runfei Huazhuo Xingxue decoction twice a day from the 4th week of instilling PM2.5 suspension until the end of experiment. In the normal control group, the mice were fed as usual. At the end of the experiment, the total protein content in bronchoalveolar lavage fluid (BALF), and lung wet/dry weight (W/D) ratio was determined. Hematoxylin-eosin (HE) staining was used to observe the histopathological changes in lung tissue under light microscope. The inflammatory mediators levels in lung tissue were determined by antibody-sandwich enzyme linked immunosorbent assay (ELISA). Results Respiratory system damage model was successfully reproduced by dripping of PM2.5 suspension in nasal cavity. Compared with normal control group, inflammatory changes and inflammatory cell infiltration in model group were significant, and lung W/D ratio (4.71±0.33 vs. 3.13±0.12), total protein content in BALF (mg/L: 363.98±18.24 vs. 82.13±12.78), tumor necrosis factor-α [TNF-α (ng/L): 185.72±0.23 vs. 31.03±0.16], interleukin-8 [IL-8 (ng/L): 531.85±37.83 vs. 72.64±16.72], and leukotriene B4 [LTB4 (ng/L): 931.74±48.64 vs. 483.81±41.74] in lung tissue were significantly increased (all P < 0.05). Compared with the model group, the inflammatory changes of lung tissue in Qingzao Runfei Huazhuo Xingxue decoction intervention group were significantly reduced, lung W/D ratio (3.92±0.41 vs. 4.71±0.33), total protein content in BALF (mg/L: 213.21±19.62 vs. 363.98±18.24), TNF-α (ng/L: 124.15±0.27 vs. 185.72±0.23), IL-8 (ng/L: 238.42±35.82 vs. 531.85±37.83) and LTB4 (ng/L: 582.85±31.00 vs. 931.74±48.64) levels in lung tissue in Qingzao Runfei Huazhuo Xingxue decoction intervention group were significantly decreased (all P < 0.05). Conclusion Qingzao Runfei Huazhuo Xingxue decoction can improve PM2.5-induced damage and pathological inflammatory changes in lung tissue, which provided some new ideas for the treatment of PM2.5-induced respiratory diseases.