The cytosolic liver-specific growth factor-hepatic stimulator substance (HSS) has been shown to be able to amplify the rat hepatocyte proliferation responded to EGF. In order to get more insight into the mechanism, th...The cytosolic liver-specific growth factor-hepatic stimulator substance (HSS) has been shown to be able to amplify the rat hepatocyte proliferation responded to EGF. In order to get more insight into the mechanism, the regulatory effect of HSS on EGF-receptor(EGF-R) and the receptor phosphorylation at molecular level was studied. HSS partially purified from weanling rat liver was given to cultured hepatocytes and its influence on EGF-R specific binding and internalization as well as mRNA expression were investigated. The results showed that preincubation of hepatocytes with HSS could lead to an increase in [125I]-EGF binding to its receptors and inhibit EGFinduced receptor down-regulation. Furthermore, the overexpression of EGF-R mRNA stimulated by HSS was seen during 2-12 h after the incubation. Additionally, it was demonstrated with human hepatoma sMMC-7721 cells in Western blot that the EGF-R expression and the receptor autophosphorylation were increased with dose/timedependency after HSS treatment. These results strongly suggest that the mechanism of HSS action on hepatocyte growth might be related to its modulation on EGF-R and receptor-mediated signaling transduction.展开更多
Aim To purify hepatocyte regeneration stimulatory factor from shark liver and research its molecular feature and activity. Methods and Results Hepatocyte regeneration stimulatory factor (sHRSF) was isolated from hea...Aim To purify hepatocyte regeneration stimulatory factor from shark liver and research its molecular feature and activity. Methods and Results Hepatocyte regeneration stimulatory factor (sHRSF) was isolated from healthy shark livers and separated by homogenization, freezing melting, heat treating, centrifugation, and ultrafiltration. HRSF activity was found mainly in the subfraction of molecular weight less than 30 000 daltons. This crude ultrafiltrate was further purified successively by DEAE Sepharose fast flow chromatography, FPLC Resource 30Q, Resource Q and Mono Q chromatography. A single band was displayed on sodium dodecyl sulfate polyacrylamide gel electrophoresis, which corresponds to molecular weight of 14 600 daltons. The characteristic absorption was obtained at the wavelength 276 nm. The isoelectric point was about 5 1. It contained 18 amino acids and the 15 N terminal amino acid residues were LVGPIGAVGPAGKDG. It had a significant activity in stimulating liver to regenerate. Conclusion We obtained an unknown new active protein, that is hepatocyte regeneration stimulatory factor from shark liver (sHRSF).展开更多
IM To partially isolate and identify hepatic stimulator substance mRNA from human fetal liver tissues.METHODS The poly (A)mRNA was extracted from human fetal liver tissues of 4-5 month gestation, fractionated by s...IM To partially isolate and identify hepatic stimulator substance mRNA from human fetal liver tissues.METHODS The poly (A)mRNA was extracted from human fetal liver tissues of 4-5 month gestation, fractionated by size on sucrose gradient centrifugation, translated into protein from each fraction in vitro and then its products were tested for HSS activity.RESULTS Twentytwo 500μg total RNA was obtained from human fetal liver tissues and pooled. mRNA of 420μg was yielded, processed by oligo(dT)cellulose column chromatography, then was sizefractionated by ultracentrifution on a continuous sucrose density gradient (5%-25%), and separated into 18 fractions. Translated products of mRNA in fraction 8 and 9 could produce a twofold increase in the incorporation of 3HTdR into DNA of SMMC7721 hepatoma cells and in a heatresistant and organspecific way.CONCLUSION The partially purified HSS mRNA was obtained and this would facilitate the cloning of HSS using expression vectors.展开更多
AIM: To examine the protective effect of estradiol on the cultured hepatocytes under oxidative stress. METHODS: Hepatocytes of rat were isolated by using perfusion method, and oxidative stress was induced by a serum-f...AIM: To examine the protective effect of estradiol on the cultured hepatocytes under oxidative stress. METHODS: Hepatocytes of rat were isolated by using perfusion method, and oxidative stress was induced by a serum-free medium and FeNTA. MDA level was determined with TBA method. Cell damage was assessed by LDH assay. Apoptosis of hepatocytes was assessed with cytoflowmetric analysis. Expression of Bcl-xl in cultured hepatocytes was detected by Western blot. The radical-scavenging activity of estradiol was valued by its ability to scavenge the stable free radical of DDPH. RESULTS: Oxidative stress increased LDH from 168 +/- 25 x 10(-6)IU.cell(-1) to 780 +/- 62 x 10(-6)IU.cell(-1) and MDA(from 0.28 +/- 0.07 x 10(-6)nmol.cell(-1) to 1.35 +/- 0.12 x 10(-6)nmol.cell(-1)) levels in cultured hepatocyte, and estradiol inhibited both LDH and MDA production in a dose dependent manner. In the presence of estradiol 10(-6)mol.L(-1), 10( -7 )mol.L(-1) and 10(-8)mol.L(-1),the LDH levels are 410 +/- 53 x 10(-6)IU.cell(-1) (P【0.01 vs oxidative group), 530 +/- 37 X 10(-6)IU.cell(-1 ) (P【0.01 vs oxidative group), 687+/-42 x 10(-6)IU.cell(-1) (P【0.05 vs oxidative group) respectively, and the MDA level are 0.71+/-0.12 x 10(-6)nmol.cell(-1) (P【0.01 vs oxidative group),0.97+/-0.11 x 10(-6)nmol.cell(-1 )(P【0.01 vs oxidative group) and 1.27+/-0.19 x 10(-6)nmol.cell(-1) respectively. Estradiol suppressed apoptosis of hepatocytes induced by oxidative stress, administration of estradiol(10(-6)mol/L)decreased the apoptotic rate of hepatocytes under oxidative stress from 18.6 +/- 1.2% to 6.5 +/-2.5%, P【0.01. Bcl-xl expression was related to the degree of liver cell damage due to oxidative stress, and estradiol showed a protective action. CONCLUSION: Estradiol protects hepatocytes from oxidative damage by means of its antioxidant activity.展开更多
Fulminant hepatitis is a serious and complex disease with high mortality. In recent years, hepatocyte growth-promoting factors (pHGF), developed on the basis of fetal liver cell injection, has been jointly used as a c...Fulminant hepatitis is a serious and complex disease with high mortality. In recent years, hepatocyte growth-promoting factors (pHGF), developed on the basis of fetal liver cell injection, has been jointly used as a comprehensive therapy for fulminant hepatitis. The following is a report of the results of using pHGF for the treatment of 1687 cases of fulminant hepatitis (with 1196 controls).展开更多
文摘The cytosolic liver-specific growth factor-hepatic stimulator substance (HSS) has been shown to be able to amplify the rat hepatocyte proliferation responded to EGF. In order to get more insight into the mechanism, the regulatory effect of HSS on EGF-receptor(EGF-R) and the receptor phosphorylation at molecular level was studied. HSS partially purified from weanling rat liver was given to cultured hepatocytes and its influence on EGF-R specific binding and internalization as well as mRNA expression were investigated. The results showed that preincubation of hepatocytes with HSS could lead to an increase in [125I]-EGF binding to its receptors and inhibit EGFinduced receptor down-regulation. Furthermore, the overexpression of EGF-R mRNA stimulated by HSS was seen during 2-12 h after the incubation. Additionally, it was demonstrated with human hepatoma sMMC-7721 cells in Western blot that the EGF-R expression and the receptor autophosphorylation were increased with dose/timedependency after HSS treatment. These results strongly suggest that the mechanism of HSS action on hepatocyte growth might be related to its modulation on EGF-R and receptor-mediated signaling transduction.
基金NationalMarine863Project (No .2 0 0 1AA62 40 90),NationalNaturalScienceFoundationofChina (No .3 0 17110 3 )
文摘Aim To purify hepatocyte regeneration stimulatory factor from shark liver and research its molecular feature and activity. Methods and Results Hepatocyte regeneration stimulatory factor (sHRSF) was isolated from healthy shark livers and separated by homogenization, freezing melting, heat treating, centrifugation, and ultrafiltration. HRSF activity was found mainly in the subfraction of molecular weight less than 30 000 daltons. This crude ultrafiltrate was further purified successively by DEAE Sepharose fast flow chromatography, FPLC Resource 30Q, Resource Q and Mono Q chromatography. A single band was displayed on sodium dodecyl sulfate polyacrylamide gel electrophoresis, which corresponds to molecular weight of 14 600 daltons. The characteristic absorption was obtained at the wavelength 276 nm. The isoelectric point was about 5 1. It contained 18 amino acids and the 15 N terminal amino acid residues were LVGPIGAVGPAGKDG. It had a significant activity in stimulating liver to regenerate. Conclusion We obtained an unknown new active protein, that is hepatocyte regeneration stimulatory factor from shark liver (sHRSF).
文摘IM To partially isolate and identify hepatic stimulator substance mRNA from human fetal liver tissues.METHODS The poly (A)mRNA was extracted from human fetal liver tissues of 4-5 month gestation, fractionated by size on sucrose gradient centrifugation, translated into protein from each fraction in vitro and then its products were tested for HSS activity.RESULTS Twentytwo 500μg total RNA was obtained from human fetal liver tissues and pooled. mRNA of 420μg was yielded, processed by oligo(dT)cellulose column chromatography, then was sizefractionated by ultracentrifution on a continuous sucrose density gradient (5%-25%), and separated into 18 fractions. Translated products of mRNA in fraction 8 and 9 could produce a twofold increase in the incorporation of 3HTdR into DNA of SMMC7721 hepatoma cells and in a heatresistant and organspecific way.CONCLUSION The partially purified HSS mRNA was obtained and this would facilitate the cloning of HSS using expression vectors.
文摘AIM: To examine the protective effect of estradiol on the cultured hepatocytes under oxidative stress. METHODS: Hepatocytes of rat were isolated by using perfusion method, and oxidative stress was induced by a serum-free medium and FeNTA. MDA level was determined with TBA method. Cell damage was assessed by LDH assay. Apoptosis of hepatocytes was assessed with cytoflowmetric analysis. Expression of Bcl-xl in cultured hepatocytes was detected by Western blot. The radical-scavenging activity of estradiol was valued by its ability to scavenge the stable free radical of DDPH. RESULTS: Oxidative stress increased LDH from 168 +/- 25 x 10(-6)IU.cell(-1) to 780 +/- 62 x 10(-6)IU.cell(-1) and MDA(from 0.28 +/- 0.07 x 10(-6)nmol.cell(-1) to 1.35 +/- 0.12 x 10(-6)nmol.cell(-1)) levels in cultured hepatocyte, and estradiol inhibited both LDH and MDA production in a dose dependent manner. In the presence of estradiol 10(-6)mol.L(-1), 10( -7 )mol.L(-1) and 10(-8)mol.L(-1),the LDH levels are 410 +/- 53 x 10(-6)IU.cell(-1) (P【0.01 vs oxidative group), 530 +/- 37 X 10(-6)IU.cell(-1 ) (P【0.01 vs oxidative group), 687+/-42 x 10(-6)IU.cell(-1) (P【0.05 vs oxidative group) respectively, and the MDA level are 0.71+/-0.12 x 10(-6)nmol.cell(-1) (P【0.01 vs oxidative group),0.97+/-0.11 x 10(-6)nmol.cell(-1 )(P【0.01 vs oxidative group) and 1.27+/-0.19 x 10(-6)nmol.cell(-1) respectively. Estradiol suppressed apoptosis of hepatocytes induced by oxidative stress, administration of estradiol(10(-6)mol/L)decreased the apoptotic rate of hepatocytes under oxidative stress from 18.6 +/- 1.2% to 6.5 +/-2.5%, P【0.01. Bcl-xl expression was related to the degree of liver cell damage due to oxidative stress, and estradiol showed a protective action. CONCLUSION: Estradiol protects hepatocytes from oxidative damage by means of its antioxidant activity.
文摘Fulminant hepatitis is a serious and complex disease with high mortality. In recent years, hepatocyte growth-promoting factors (pHGF), developed on the basis of fetal liver cell injection, has been jointly used as a comprehensive therapy for fulminant hepatitis. The following is a report of the results of using pHGF for the treatment of 1687 cases of fulminant hepatitis (with 1196 controls).
