ABSTRACT
Aim To investigate the damage degree of doxorubicin hydrochloride( DOX )on cardiac function in rats, and to explore its possible mechanism. Methods Experiment 1: SD rats( n=48 )were randomly divided into control group( normal saline ), DOX 1 group( DOX cumulative dose 12 mg·kg-1 ;intraperitoneal injection ), DOX 2 group( 15 mg·kg-1 ;)and DOX 3 group( 18 mg·kg-1 ;). Cardiac structure and cardiac function were detected by echocardiography. B-type natriuretic peptide( BNP )was detected by ELISA. The morphological changes of myocardium were observed by Hematoxylin-eosin( HE )staining. The optimal dose group( DOX 2 group )was selected comprehensively. Experiment 2: SD rats( n=36 )were randomly divided into control group( normal saline ), DOX 2 group(15 mg·kg-1)and DOX 2+Mdivi-1 group( 15 mg·kg-1+daily abdominal injection of Mdivi-1(1 mg ·kg-1 ;)). Western blot was used to detect the protein expression of myocardial mitochondrial dynamics. Results Compared with the control group, hearts in DOX groups were enlarged and the heart function was reduced. Under the microscope, hypertrophy of cardiac cells and loose arrangement of cardiac fibers were observed in DOX group, and the higher the cumulative dose of DOX in rats, the more severe the degree of heart failure and the higher the mortality rate of rats. Compared with control group, the expression of mitochondrial dynamin-related protein 1( DRP1 )and related signaling pathway protein FUN14 domain containing 1( FUNDC1 )in DOX 2 group increased. The expression of optic atrophy 1( OPA1 )decreased, the expression of FUNDC1 and DRP1 protein decreased, and the expression of OPA1 protein was enhanced after the use of mitochondrial dynamics inhibitor(Mdivi-1). Conclusions DOX can cause chronic heart failure, and the mechanism may be related to DRP1/FUNDC1 mediated mitochondrial fission and fusion.
ABSTRACT
OBJECTIVE： To investigate the effects of Buyang huanwu decoction on endothelial-mesenchymal transformation （EndMT） of lung tissue in idiopathic pulmonary fibrosis （IPF） model rats， and to explore its potential mechanism. METHODS： Male SD rats were randomly divided into normal group， model gorup， dexamethasone group [0.405 mg/（kg·d）]， Buyang huanwu decoction low-dose， medium-dose and high-dose groups [6.435， 12.87， 25.74 g/（kg·d）， by raw material]， with 8 rats in each group. Except for normal group， other groups were given endotracheal injection of bleomycin to induce IPF model. On the second day after modeling， normal group and model group were given water intrgastrically [10 mL/（kg·d）]； administration groups were given relevant medicine intragastrically， once a day， for consecutive 28 days. 24 h after last medication， the expression of endothelial cell markers [platelet endothelial cell adhesion molecule 1， vascular endothelial cell cadherin] and interstitial cell markers [α-smooth muscle actin， fibroblast specific protein 1] were detected by immunohistochemistry method. The expression of Notch4 and DLL4 in lung tissue of rats were detected by Western blotting assay. RESULTS： Compared with normal group， the expression of endothelial cell markers were decreased significantly in lung tissue of model group， while the expressipon of interstitial cell markers， Notch4 and DLL4 were increased significantly （P＜0.01）. Compared with model group， the expression of endothelial cell markers in lung tissue of rats were increased significantly in administration groups， while Buyang huanwu decoction low-dose group was significantly lower than dexamethasone group； the expression of interstitial cell markers， Notch4 and DLL4 were decreased significantly， while Buyang huanwu decoction low-dose group was significantly higher than dexamethasone group （P＜0.05 or P＜0.01）. CONCLUSIONS： Buyang huanwu decoction can relieve IPF of model rats by intervening in EndMT， the mechanism of which may be associated with inhibiting DLL4/Notch4 singaling pathway.
ABSTRACT
Objective To investigate the effect of silencing Notch1 gene by RNA interference on the proliferation,apoptosis and Akt/mTOR signaling pathway in clear renal cell carcinoma.Methods The optimal segment targeting Notch1 gene was designed and transfected into 786-O cells by Lipofectamine TM2000.The Notch1 mRNA and protein were detected by RT-PCR and Western blot.The proliferation rate of 786-O cells was evaluated by MTT and the variation of apoptosis was measured by TUNEL.The protein expression level of apoptosis-related protein Bcl-2,caspase-3,caspase-9,and signaling pathway protein Akt,p-Akt,p-mTOR,p-P70S6K were detected by Western blott.Results Notchl mRNA and protein was markedly suppressed by the siRNA targeting Notch1.Treated with 0,40,60,80,100 and 120 nmol/L of Notch1 siRNA for 24 hours,cell proliferation rates were (98.51 ± 1.33) ％,(87.34 ± 2.26) ％,(64.72 ± 3.24)％,(57.68 ±3.32)％,(31.91 ± 1.85)％ and (19.27 ±2.73)％,and the difference was statistically significant (P ＜ 0.01).Treated with 0,40,80,and 120 nmol/L of Notchl siRNA for 24 hours,apoptosis rates were (7.6 ± 3.8) ％,(21.5 ± 4.8) ％,(32.3 ± 3.5) ％,and (46.3 ± 4.7％),the difference was statistically significant (P ＜ 0.05).Decreased expression of Akt signaling pathway proteins p-Akt,p-mTOR,p-70S6K and apoptosis-related protein Bcl-2,procaspase-3 was detected,but no change in the total protein of Akt.Conclusions Depletion of Notch1 gene could inhibit cell growth and induce apoptosis in 786-O cell line.It inhibits Akt/mTOR signaling pathway by dephosphorylated.