Research Of Functional Mechanism On IPF Rats' Extracellular Matrix With YQYYQYF (Yiqiyangyinquyufang)

Objective: To observe the effect of YF on ECM of IPF rats induced by bleomycin, approach its functional mechanism, and explore the possible mechanisms of IPF from the view of TCM, which will provide practical and theoretical evidence for developing new method of treating and preventing IPF.Methods: 120 healthy SD rats (paroecious about half) raised in the experimental environment about one week were randomly divided into five groups (24 per-group):①control group: pyrogen-free normal saline (NS, 200μl per rat) was instilled intratracheally;②model group,③low-dose group,④high-dose group and⑤prednisone group: bleomycin A5 was instilled intratracheally (5mg·kg-1). From the second day after instillation, control group and model group were filled with NS (10ml/kg),drenched by isotonic Na chloride; low-dose group and high-dose group were drenched with Chinese crude drug elixation differently(12.3g·kg-1 and 24.6 g·kg-1,7 and 14 times the dosage of the adult's clinical drug consumption); prednisone group were drenched with prednisone(6mg·kg-1).Rats in each group were respectively sacrificed on the 7th, 14th and 28th day after instillation. Serum was remained and bronchoalveolar lavage (BAL) was done on the rats in each group to detect the contents of HA and LN in serum and bronchoalveolar lavage fluid (BALF). 10% homogenate of lung tissue was prepared to test HYP contents. Polyoxymethylene of 4% was to fix the lung, routine paraffin imbedded and bladed, histomorphology changes of lung tissues were observed by HE and Masson dyeing, and the expression of TGF-β1 on the lung was detected by immunohistochemistry.Results:1 Observation of the common condition Control group ate and drunk normally, reacted sensitively, the fur was luster, the urine and stool were normal, with no death. Model group scrunched, coughed and breathed difficultly, had listlessness and withered fur. High-dose group and low-dose group gradually had the better mind, fur and appetite, breathed smoothly, and their activity increased; prednisone group alsohad better condition, but inferior to high-dose group and low-dose group.2 Observation of the lung's histomorphology2.1 Macroscopic observation: The lung's appearance of control group was normal with color pink, surface smooth, elasticity good and lobes of lung edge sharpness. Of model group, lungs on 7th day were bigger and spotty hemorrhage and ecchymosis were seen; lungs on 14th day were gray, on which there were inequality of size nodus, sppotty hemorrhage; on 28th day, lungs were gray, smaller and harder, with nodus and bead-like aerate vacuole on the surface. The lung's appearance of each treatment group was better than that of model group.2.2 Obeservation under light microscope: Severe injuries were observed in lung tissues of model group, which were characterized by widened septa of alveoli, diffuse infiltration of inflammatory cells accompanied by atrophied or disappeared alveolitis, and compensatory alveolar emphysema. In the late period, midrange or severe pulmonary interstitial fibrosis developed; more collagenous fibers in lung matrix were observed by Masson dyeing. Compared with model group, alveolitis and pulmonary fibrosis of each treatment group were declined significantly, especially in high-dose group.3 Effect of YQYYQYF on the ECMThe results were as follows: Compared with the same time points of control group, all the parameters including the contents of HYP in lung tissues, HA and LN in serum and BALF were increased in model group(all P<0.01).Compared with model group at the same time points, all the parameters were decreased in the three treatment groups(P<0.05 or P<0.01);compared with prednisone group, the contents of HYP were decreased in high-dose group on 14th and 28th day(P<0.05 or P<0.01), the contents of HA in BALF were decreased in high-dose group on 28th day(P<0.05), the contents of LN in BALF were decreased in high-dose on 7th day(P<0.05) and the contents of it in BALF and serum were decreased in high-dose and low-dose group on 28th day(P<0.05 or P<0.01). 4 Effect of YQYYQYF on the expression of TGF-β1 in lungsThe results were as follows: The control group had poor expressions in the lung tissue; compared with the same time points of control group, the degree of TGF-β1's expression were enhanced in model group; compared with model group at the same time points, the expression were decreased in the three treatment groups (all P < 0.01). There was no statistical significance among three treatment groups (all P>0.05).Conclusion:1 Duplicate IPF model by dripping BLM in the airtube, the common condition and pathomorphism of lung tissue consistent with the typical patho-character of IPF, YQYYQYF improves the change of pulmonary patho-morphous.2 Under the condition of IPF, the contents of ECM in the blood serum and tissue changing obviously, indicates that ECM participate the formation of PF; YQYYQYF inhibit PF through effecting on deposition of ECM.3 Under the condition of IPF, lung tissue having hypso- expression character of TGF-β1, indicates TGF-β1 promotes the fibrosis formation; YQYYQYF relieves the degree of PF through down-regulating expression of TGF-β1 to inhibit the deposition of ECM.