穿心莲内酯对博来霉素致肺纤维化大鼠肺组织羟脯氨酸和PDGF表达的影响

Effect of Andrographolide on Expression of Hydroxyproline and PDGF in Lung Tissue of Bleomycin-induced Rat Pulmonary Fibrosis

目的观察穿心莲内酯(AND)灌胃对博来霉素(BLM)致肺纤维化大鼠肺组织羟脯氨酸(HYP)和血小板源性生长因子(PDGF)表达的影响。方法取健康雄性SD大鼠90只,随机分为生理盐水(NS)组、BLM组、泼尼松(Pred)组、不同剂量AND组(即AND A组62.5mg/kg、AND B组125mg/kg、AND C组250mg/kg),各组大鼠15只,气管内分别灌注BLM(BLM组、Pred组、AND各组)或NS(NS组)后,每天给予NS(NS组、BLM组)、Pred(Pred组)或AND(AND各组)灌胃,各组分别于气管内灌注药物后第7,14,28天处死大鼠各5只。肺组织HE染色和Masson染色观察肺泡炎和肺纤维化改变;全自动生化分析仪检测大鼠血清肝功能指标丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)和肾功能指标尿素氮(BUN)、肌酐(Cr);用对二甲氨基苯甲醛法检测肺组织匀浆HYP的含量;用免疫组化的方法测定肺组织中PDGF蛋白的表达。结果①NS组大鼠肺组织未见肺泡炎和肺纤维化形成;BLM组第7天时肺泡炎较明显,第14天时有所减轻,出现肺纤维化,第28天时肺泡炎继续减轻,肺纤维化程度加重;AND A组病理形态改变与BLM组相似;Pred组、AND B组、AND C组大鼠第7天有较多的炎症细胞浸润及局部聚积,第14天和第28天的纤维化病理改变均较BLM组、AND A组明显减轻。②肝肾功能指标检测显示:BLM组、Pred组、不同剂量AND组分别与NS组比较,差异无统计学意义(P>0.05)。③NS组肺组织HYP含量较少,与NS组比较,其他各组大鼠肺组织HYP含量均明显增加;与BLM组比较,Pred组、不同剂量AND组各时间点HYP含量均降低;与Pred组比较,AND B组、AND C组第7天、14天时HYP含量降低;以上比较差异均有统计学意义(P<0.05)。④NS组肺组织中PDGF表达较少;与NS组比较,各组大鼠肺组织PDGF表达均显著增加;与BLM组比较,Pred组、不同剂量AND组不同时间点PDGF表达均降低;与Pred组和AND A组比较,ANDB组、AND C组第7天、14天时PDGF表达均降低;以上比较差异均有统计学意义(P<0.05)。结论一定剂量AND灌胃可减轻BLM致肺纤维化大鼠肺泡炎、降低肺组织HYP含量和减少肺组织中PDGF的表达,从而减轻纤维化程度,且对肝肾无明显毒副作用。

ObjectiveTo observe the effect of andrographolide（AND） on the expression of hydroxyproline（HYP）and platelet derived growth factor（PDGF） in lung tissue of bleomycin-induced rat pulmonary fibrosis. MethodsNinety adult male SD rats were randomly divided into six groups： normal saline（NS） group,bleomycin（BLM） group,prednisone（Pred） and different doses of AND groups（AND A group 62.5mg/kg,AND B group 125mg/kg and AND C group 250mg/kg）.Intratracheal instillation of BLM was given to BLM group,Pred group and AND groups,while NS group with 0.9% NaCl solution（NS）.Each group was again divided into 3 subgroups,which were sacrificed on days 7,14 and 28.HE and Masson staining were performed to observe the extent of alveolitis and fibrosis;Blood urea nitrogen（BUN）,creatinine（Cr） and alanine aminotransferase（ALT）,aspartate aminotransferase（AST） were examined;HYP content was also detected;PDGF protein in lung tissue was assessed by immunohistochemistry. Results①Alveolitis and fibrosis could not be fourd in NS group.A great deal of inflammatory cell infiltration into the alveolar were observed in BLM group on day 7,the alveolitis was less on day 14,while fibrosis was found,and on day 28 the alveolitis became less and the fibrosis became serious.It was similar in pathomorphology between AND A group and BLM group.A lot of inflammatory cell infiltration and local accumulation were observed on day 7 in groups AND B,C and Pred.The pathological change of fibrosis on days 14,28 had more significant reduction than groups AND A and BLM.②There was no statistical difference for the contents of serun BUN,Cr,ALT,AST among the six groups（P0.05）.Compared with BLM group,the content of HYP and the expression of PDGF in Pred group and all AND groups were lowered on days 7,14,28;Compared with Pred group,the content of HYP and AND B and C groups were decreased on days 7,14. ConclusionA certain dose of AND can abate the alveolitis,decrease the levels of PDGF protein and HYP in lung tissue,ameliorate the extent of pulmonary fibrosis,and there is no toxic side effect of liver and kidney in BLM-induced rat pulmonary fibrosis.