| Hepatic fibrosis , of which cirrhosis is the most advanced stage , can result from chronic liver disease due to any cause .The current view envisions fibrosis as a programmed response to injury ,which is dynamic and reversible .The main pathological characteristic of hepatic fibrosis is the increased and irregular deposition of extracellular matrix (ECM) components. Hepatic stellate cells (HSCs) play a pivotal role in this process .The activation of HSCs may result in their spontaneous proliferation with a strong fibrogenic activity .In recovery period , the apoptosis of HSCs increases significantly .So the proliferation and apoptosis of HSCs play a key role in the process of formation and resolution of hepatic fibrosis . Integrins are the main mediators of the complicated interaction between HSCs and ECM components. A number of observations strongly suggest that ligand occupy ,integrin receptor clustering and their combination trigger the aggregtion of focal adhesion kinase (FAK) in focal adhesion plaque (FAP) and autophosphorylation of FAK at Tyr397 in the N-terminal domain .The activation of FAK may initiate two signaling pathways:on one hand ,FAK autophosphorylation at Tyr-397 creates a high affinity binding site for the SH2 and SH3 domains of Src and then reduces phosphorylation of tensin ,talin ,paxilin and so on ,which initiates RAS-dependent mitogen-activated protein kinase (MAPK) pathway ; on the other hand ,phosphorylation of FAK creates a binding site for the Grb2 and mSOS ,and then initiates RAS-dependent MAPK pathway . Up to now , the effects of ECM components such as osteopontin (OPN) on vascular smooth muscle cells (VSMC) adhesion ,migration and changes of aortic FAK have been reported , but few studies have addressed the effects of OPN on HSCs . Hence ,we set about our research from the interaction of HSCs and ECM .We studied the role of integrin signaling pathways in HSCs adhesion ,migration and the changes of aortic FAK .The experiments contained two parts as below :Part one : The effects of osteopontin on adhesion ,migration and proliferation of HSCs Objective: To explore the effects of OPN on adhesion ,migration and proliferation of HSCs. Methods: The proliferation of HSCs was determined by MTT .The adhesion rates were observed by toluidine blue colorimetric assay .And the migration rates of HSCs were examined by hematoxylin and eosin staining . Results: ①Compared with control group , OPN at concentrations of 8μg·mL-1 , 16 μg·mL-1 and 32 μg·mL-1 promoted the adhesion of HSCs .The promotion rates were 55.65% , 58.67% and 45.25% , respectively P<0.05 . Although they have no difference each other ; Compared with control group , RGDS tetra peptide at concentrations of 25μg·mL-1 , 50 μg·mL-1 and 100μg·mL-1 inhabited the adhesion of HSCs . The inhabition rates were 13.34% , 16.55% and 36.31% , respectively (P<0.05) . The RGES group changed little vs control group . ② After adding OPN to HSCs for 48 h ,the promoted proliferation rates of OPN at concentrations of 8μg·mL-1 , 16 μg·mL-1 and 32μg·mL-1 were 11.12% , 13.54% and 10.47% , respectively and the promoted proliferation rates of 16μg·mL-1 at 24h , 48 h , 72 h and 96h were 34.12% , 35.63% , 34.37% and 34.96% , respectively . After adding RGDS tetrapeptide to HSCs for 48 h , the inhabition rates of RGDS tetrapeptide at concetrations of 25μg·mL-1 , 50μg·mL-1 and 100μg·mL-1 were 5.84% , 12.53% and 29.49% , rspectively and the inhabition rate of 100μg·mL-1 at 24h , 48h ,72h and 96h were 8.53% , 13.74% , 17.14% and 22.98% , respectively . RGES tetrapeptide has no effect on proliferation of HSCs . ③ The control group migrated distances at 12h , 24h and 36h were (75.00±10.18)μm,(97.00±13.37)μm,and(78.00±13.17)μm , respectively .The migrated distances of OPN at concentration of 16μg·mL-1 at 12h , 24h , and 36h were (93.00±4.83)μm , (114.00±9.66)μm and (121.00±17.29)μm , respectively .The migrated lengthes of RGDS tetrapeptide (at concentrat...
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