Sixty cases of hepatocellular carcinoma (HCC) and 47 cases of liver cirrhosis (LC) were examined with immunocytochemistry method using antibodies against IGF-II and HBxAg on formalin-fixed, paraffin-embedded tissue se...Sixty cases of hepatocellular carcinoma (HCC) and 47 cases of liver cirrhosis (LC) were examined with immunocytochemistry method using antibodies against IGF-II and HBxAg on formalin-fixed, paraffin-embedded tissue sections. 32 HCC and 37 LC were found to be positive to HBxAg, in which the positive rates of IGF-II were 100% (32/32) and 94.6% (35/37) respectively. 28 HCC and 10 LC were found to be HBxAg negative, IGF-II was positive in 23 HCC (83.1%) and 6 LC (60%). The positive expression rates of IGF-II in HBxAg positive tissues were significantly higher than those in HBxAg negative tissues (P<0.05). There were three types of distribution of IGF-II expression in HCC and LC: (1) perinucleus; (2) diffuse in cytoplasm; (3) inside nucleus. IGF-II was highly expressed in most of hyperplastic and neoplastic nodules hepatocytes and some of regeneration nodules. Small polygonal liver cells (SPLCs) were found in the liver tissues surrounding the tumor and cirrhosis and they were positive to both IGF-II and HBxAg. The positive rates of IGF-II in SPLC were 86.4% (38/44) in the HBxAg-positive tissues and 40.5%, (15/37) in the HBxAg-negative tissues. The above findings suggest that IGF-II plays an important role in abnormal proliferation of HCC and SPLC. The relation between IGF-II andHBxAg and the nature of SPLCs are also discussed.展开更多
The DNA sequence encoding the chicken＇s insulin-like growth factor Ⅰ （IGF-Ⅰ） was amplified with the reverse transcription polymerase chain reaction （RT-PCR）, which was then cloned into vector pMD18-T and sequen...The DNA sequence encoding the chicken＇s insulin-like growth factor Ⅰ （IGF-Ⅰ） was amplified with the reverse transcription polymerase chain reaction （RT-PCR）, which was then cloned into vector pMD18-T and sequenced. The sequencing result showed that there was 100% homology among the documented sequences and the sequence reported in this article, which was successfully inserted into the expressing plasmid pRLC and was highly expressed in E.coli. The Tricine-SDS- PAGE result showed that the cloned recombinant protein was expressed in the form of inclusion bodies in the E.coli cell with molecular weight of 7.6 kD and was amount to 23% of the whole protein in the E.coli cell. Western blotting indicated that recombinant protein had the antigenicity of IGF- Ⅰ. The inclusion bodies were subsequently dissolved in 7 M guanidine chloride and renatured with dilution in refolding buffer containing 0.5 M arginine. To obtain pure protein, the renatured chicken IGF- Ⅰ was desalting by Hiprep 26/10 and purified by Hiprep Sephacryl S-200 chromatography. The biological activities of IGF- Ⅰ product were assayed in NIH 3T3 cells and osteoblastic cells of embryonic chicken by using MTT method. The results show that the expressed IGF- Ⅰ can obviously stimulate NIH3T3 cells and osteoblastic cells to proliferate at the concentration ranging from 100, 200, 400 to 800 ng mL^-1, suggesting that the protein has its biological activities.展开更多
Severe acute pancreatitis （SAP） can result in intestinal mucosal barrier （IMB） dysfunction. This study was undertaken to demonstrate the effect of IGF-I on the intestinal mucosal barrier in rats with SAP and its p...Severe acute pancreatitis （SAP） can result in intestinal mucosal barrier （IMB） dysfunction. This study was undertaken to demonstrate the effect of IGF-I on the intestinal mucosal barrier in rats with SAP and its possible mechanisms. Seventy-two male Wistar rats were randomly divided into three groups： a sham operation （SO group, n=24）, a SAP group not treated with IGF-I （SAP group, n=24）, and a SAP group treated with IGF-I （IGF-I group, n=24）. SAP was induced in the rats by injecting 5.0% sodium taurocholate into the biliary-pancreatic duct. The SO rats were given an infusion of normal saline instead. The rats in the IGF-I group underwent the SAP procedure and were given a subcutaneous injection of IGF-I at 30 minutes before the operation and at 3 hours after the operation. Eight rats in each group were sacrificed at 6, 12 and 24 hours after operation. Apoptosis of mucosal cells in the small intestine was determined by TUNEL. The levels of endotoxin and DAO and serum amylase were also measured. Pathologic changes in the small intestine were monitored. Changes of bax and bcl-2 mRNA expression in the small intestine were determined by reverse transcription polymerase chain reaction （RT-PCR）. The levels of serum amylase were lower in the IGF-I group than in the SAP group at all three time points （P〈0.05）. The levels of endotoxin in the IGF-I group were higher than those in the SAP group at 6 hours, but lower in the IGF-I group than in the SAP group at 12 and 24 hours （P〈0.05）. The levels of diamine oxidase were higher in the IGF-I group at 6 hours but lower than those in the SAP group at 12 and 24 hours. The pathological score of the small intestine was lower in the IGF-I group than in the SAP group, and the difference was statistically significant at 12 and 24 hours. The pathologic changes observed under electron microscopy were better in the IGF-I group than those in the SAP group. The apoptosis index of intestinal epithelial cells was significantly decreased in the IGF-I group compared with the SAP group. Compared with the SO group, the mRNA expression levels of bax were increased at each time point in the SAP group, and were significantly decreased in the IGF-I group as compared with the SAP group at each time point （P〈0.05）. The expression levels of bcl-2 were weak and not different between the SO group and the SAP group （P〉0.05）. They were significantly increased in the IGF-I group versus the SO and SAP groups （P〈0.05）. The ratio of bax and bcl-2 mRNA expression levels at each time point in the SAP group were significantly higher than those in the SO group, but they were obviously decreased in the IGF-I group. Exogenous IGF-I seems to protect mucosal cells in the small intestine against SAP-induced apoptosis and could alleviate SAP-induced injury of the intestinal mucosa. The underlying mechanisms include enhanced mRNA expression of bcl-2 and inhibition of bax mRNA expression.展开更多
基金This work was supported by National Science Foundation of China(No.3880376)by the Medical Science Foundation fPLA.
文摘Sixty cases of hepatocellular carcinoma (HCC) and 47 cases of liver cirrhosis (LC) were examined with immunocytochemistry method using antibodies against IGF-II and HBxAg on formalin-fixed, paraffin-embedded tissue sections. 32 HCC and 37 LC were found to be positive to HBxAg, in which the positive rates of IGF-II were 100% (32/32) and 94.6% (35/37) respectively. 28 HCC and 10 LC were found to be HBxAg negative, IGF-II was positive in 23 HCC (83.1%) and 6 LC (60%). The positive expression rates of IGF-II in HBxAg positive tissues were significantly higher than those in HBxAg negative tissues (P<0.05). There were three types of distribution of IGF-II expression in HCC and LC: (1) perinucleus; (2) diffuse in cytoplasm; (3) inside nucleus. IGF-II was highly expressed in most of hyperplastic and neoplastic nodules hepatocytes and some of regeneration nodules. Small polygonal liver cells (SPLCs) were found in the liver tissues surrounding the tumor and cirrhosis and they were positive to both IGF-II and HBxAg. The positive rates of IGF-II in SPLC were 86.4% (38/44) in the HBxAg-positive tissues and 40.5%, (15/37) in the HBxAg-negative tissues. The above findings suggest that IGF-II plays an important role in abnormal proliferation of HCC and SPLC. The relation between IGF-II andHBxAg and the nature of SPLCs are also discussed.
基金This work was supported by the National Natural Science Foundation of China(30270998) Natural Science Foundation of Jiangsu Province,China(Q200443).
文摘The DNA sequence encoding the chicken＇s insulin-like growth factor Ⅰ （IGF-Ⅰ） was amplified with the reverse transcription polymerase chain reaction （RT-PCR）, which was then cloned into vector pMD18-T and sequenced. The sequencing result showed that there was 100% homology among the documented sequences and the sequence reported in this article, which was successfully inserted into the expressing plasmid pRLC and was highly expressed in E.coli. The Tricine-SDS- PAGE result showed that the cloned recombinant protein was expressed in the form of inclusion bodies in the E.coli cell with molecular weight of 7.6 kD and was amount to 23% of the whole protein in the E.coli cell. Western blotting indicated that recombinant protein had the antigenicity of IGF- Ⅰ. The inclusion bodies were subsequently dissolved in 7 M guanidine chloride and renatured with dilution in refolding buffer containing 0.5 M arginine. To obtain pure protein, the renatured chicken IGF- Ⅰ was desalting by Hiprep 26/10 and purified by Hiprep Sephacryl S-200 chromatography. The biological activities of IGF- Ⅰ product were assayed in NIH 3T3 cells and osteoblastic cells of embryonic chicken by using MTT method. The results show that the expressed IGF- Ⅰ can obviously stimulate NIH3T3 cells and osteoblastic cells to proliferate at the concentration ranging from 100, 200, 400 to 800 ng mL^-1, suggesting that the protein has its biological activities.
文摘Severe acute pancreatitis （SAP） can result in intestinal mucosal barrier （IMB） dysfunction. This study was undertaken to demonstrate the effect of IGF-I on the intestinal mucosal barrier in rats with SAP and its possible mechanisms. Seventy-two male Wistar rats were randomly divided into three groups： a sham operation （SO group, n=24）, a SAP group not treated with IGF-I （SAP group, n=24）, and a SAP group treated with IGF-I （IGF-I group, n=24）. SAP was induced in the rats by injecting 5.0% sodium taurocholate into the biliary-pancreatic duct. The SO rats were given an infusion of normal saline instead. The rats in the IGF-I group underwent the SAP procedure and were given a subcutaneous injection of IGF-I at 30 minutes before the operation and at 3 hours after the operation. Eight rats in each group were sacrificed at 6, 12 and 24 hours after operation. Apoptosis of mucosal cells in the small intestine was determined by TUNEL. The levels of endotoxin and DAO and serum amylase were also measured. Pathologic changes in the small intestine were monitored. Changes of bax and bcl-2 mRNA expression in the small intestine were determined by reverse transcription polymerase chain reaction （RT-PCR）. The levels of serum amylase were lower in the IGF-I group than in the SAP group at all three time points （P〈0.05）. The levels of endotoxin in the IGF-I group were higher than those in the SAP group at 6 hours, but lower in the IGF-I group than in the SAP group at 12 and 24 hours （P〈0.05）. The levels of diamine oxidase were higher in the IGF-I group at 6 hours but lower than those in the SAP group at 12 and 24 hours. The pathological score of the small intestine was lower in the IGF-I group than in the SAP group, and the difference was statistically significant at 12 and 24 hours. The pathologic changes observed under electron microscopy were better in the IGF-I group than those in the SAP group. The apoptosis index of intestinal epithelial cells was significantly decreased in the IGF-I group compared with the SAP group. Compared with the SO group, the mRNA expression levels of bax were increased at each time point in the SAP group, and were significantly decreased in the IGF-I group as compared with the SAP group at each time point （P〈0.05）. The expression levels of bcl-2 were weak and not different between the SO group and the SAP group （P〉0.05）. They were significantly increased in the IGF-I group versus the SO and SAP groups （P〈0.05）. The ratio of bax and bcl-2 mRNA expression levels at each time point in the SAP group were significantly higher than those in the SO group, but they were obviously decreased in the IGF-I group. Exogenous IGF-I seems to protect mucosal cells in the small intestine against SAP-induced apoptosis and could alleviate SAP-induced injury of the intestinal mucosa. The underlying mechanisms include enhanced mRNA expression of bcl-2 and inhibition of bax mRNA expression.
