蛇菰多糖降低实验性肝损伤大鼠肝脏BDNF和TrkB的表达

目的蛇菰多糖(BPS)对D-半乳糖(D-gal)所致实验性肝损伤大鼠的肝功能及肝组织内BDNF、TrkB蛋白和凋亡相关蛋白表达的影响。方法将大鼠随机分为对照组(control),D-gal组(皮下注射D-半乳糖200 mg/kg),BPS低(D-gal+BPS-L)、中(D-gal+BPS-M)、高(D-gal+BPS-H)剂量组,分别每天灌胃50、100和200 mg/kg BPS,共6周。心脏取血检测血清谷丙转氨酶(ALT)和谷草转氨酶(AST)水平;HE染色法观察肝组织形态;免疫组织化学染色检测BDNF和TrkB的定位;Western blot检测BDNF、TrkB、Bcl-2、caspase-3和Bax蛋白表达;ELISA测定肝组织内丙醛(MDA)含量和超氧化物歧化酶(SOD)活性。结果与对照组相比,D-gal组肝细胞水肿、点状坏死;血清ALT和AST水平升高(P<0.05),SOD活性降低、MDA含量升高(P<0.05);Bax、caspase-3、BDNF、TrkB表达增加(P<0.05),Bcl-2表达降低(P<0.05);与D-gal组相比,BP...

Balanophora polysaccharide decreases the expression of BDNF and TrkB in liver tissues of rat with experimental liver injury

Objective To study the effects of Balanophora polysaccharides(BPS)on the expression of BDNF,TrkB and other apoptosis-related proteins in rats with experimental liver injury induced by D-gal.MethodsRats were randomly divided into control group,D-gal group(200 mg/kg of hypodermic D-galactose),groups with BPS of low dosage(BPS-L),medium dosage(BPS-M)and high dosage(BPS-H),which were treated with intragastric administration by 50,100 and 200 mg/kg BPS per day,respectively.After six weeks,serum alanine transaminase(ALT)and aspartate aminotransferase(AST)were measured.HE staining was used to observe liver tissue morphology.The localization of BDNF and TrkB was determined by immuno-histochemical staining.Western blot was used to detect BDNF,TrkB,Bcl-2,caspase-3 and Bax protein expression.ELISA was used to determine the malondialdehyde(MDA)content and superoxide dismutase(SOD)activity in liver tissues.Results Compared with the control group,the hepatocytes showed edema and punctate necrosis in D-gal group,with increased serum level of ALT and AST(P<0.05).The results also showed decreased SOD activity and increased MDA content(P<0.05),increased Bax,caspase-3,BDNF,TrkB expression(P<0.05)and decreased Bcl-2 expression(P<0.05).Compared to D-gal group,the hepatocyte degeneration and necrosis were obviously alleviated in BPS groups with each dose accompanied by decreased serum ALT and AST levels(P<0.05),increased SOD activity and decreased MDA content(P<0.05),reduced Bax and caspase-3 expression of pro-apoptotic proteins,increased expression Bcl-2 anti-apoptotic proteins(P<0.05)and decreased expression of BDNF and TrkB(P<0.05).Conclusions Balanophora polysaccharide had a protective effect on experimental liver injury caused by D-gal.The mechanism may be related to the decrease of the expression of BDNF and TrkB followed by inhibition of hepatocyte apoptosis.