[Objective] The research aimed to enhance culture efficiencies of oocyte and embryo of goat in vitro and to explore serum-free culture system in vitro.[Method] At present,the conventional solutions of oocyte maturatio...[Objective] The research aimed to enhance culture efficiencies of oocyte and embryo of goat in vitro and to explore serum-free culture system in vitro.[Method] At present,the conventional solutions of oocyte maturation and embryo development in vitro were always added into 1% ITS(Insulin-transferrin-selenium) or using 1% ITS to replace FBS in 2 kinds culture solutions for conducting in vitro cultures of goat oocyte and parthenogenetic embryo.The influences of ITS on their developments were detected.[Result] ITS in maturation liquid of oocytes could not increase oocytes maturation rate but significantly increased blastocyst rate (58.06% vs. 48.19%)of parthenogenetic embryo.If FBS in maturation liquid of oocytes was replaced by ITS, the maturation rate, cleavage rate and blastocyst rate were basically unchanged.Adding ITS into embryo medium could increase blastocyst rate (68.30% vs. 56.82%)of parthenogenetic embryo of goat.If FBS in embryo medium was replaced by ITS,the cleavage rate didn’t change basically,while the blastocyst rate in ITS was obviously lower than that in FBS group(42.33% vs.56.82%).[Conclusion] ITS could promote maturation of oocyte in vitro and early embryonic development, in addition,ITS could replace serum in maturation medium of oocyte as serum-free culture system for conducting relevant researches.展开更多
The insulin-like growth factor(IGF) signaling path-way is an important pathway in the process of hepa-tocarcinogenesis,and the IGF network is clearly dysregulated in many cancers and developmental abnormalities.In hep...The insulin-like growth factor(IGF) signaling path-way is an important pathway in the process of hepa-tocarcinogenesis,and the IGF network is clearly dysregulated in many cancers and developmental abnormalities.In hepatocellular carcinoma(HCC),only a minority of patients are eligible for curative treatments,such as tumor resection or liver transplant.Unfortunately,there is a high recurrence of HCC after surgical tumor removal.Recent research efforts have focused on targeting IGF axis members in an attempt to find therapeutic options for many health problems.In this review,we shed lights on the regulation of members of the IGF axis,mainly by micro RNAs in HCC.Micro RNAs in HCC attempt to halt the aberrant expression of the IGF network,and a single micro RNA can have multiple downstream targets in one or more signaling pathways.Targeting micro RNAs is a relatively new approach for identifying an efficient radical cure for HCC.展开更多
Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus m...Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats.展开更多
[ Objedive] This study was aimed to determine the single nucleotide polymorphisms （SNPs） of IGF-I gene in two breeds, Wanxi white goose and Langde goose. [ Method] Two pair of primers was designed based on chicken a...[ Objedive] This study was aimed to determine the single nucleotide polymorphisms （SNPs） of IGF-I gene in two breeds, Wanxi white goose and Langde goose. [ Method] Two pair of primers was designed based on chicken and porcine genomic sequence to amplify the 5＇ regulatory region of IGF-I, and the sequence was determined and analyzed. [ Result] A total of four SNPs were identified in this region by PCR-SSCP meth- od, that is, A to T at 26 nt, A to G at 215 nt, A to G at 314 nt, and A to T at 325 nt. [ Conclusioa] The two breeds ,wanxi white geese and Langde geese, agree with Hardy-weinberg equilibrium with respect to these SNPS.展开更多
BACKGROUND： Recent studies have found that insulin-like growth factors （IGFs） and insulin-like growth factor binding protein-3 （IGFBP-3） have stronger neurotrophic and neuroprotective effects. But whether their l...BACKGROUND： Recent studies have found that insulin-like growth factors （IGFs） and insulin-like growth factor binding protein-3 （IGFBP-3） have stronger neurotrophic and neuroprotective effects. But whether their levels in cerebrospinal fluid could be used as an auxiliary indicator in differentially diagnosing tuberculous meningitis and viral encephalitis is not yet clear. OBJECTIVE： To explore the changes of insulin-like growth factor-Ⅱ （IGF-Ⅱ ） and IGFBP-3 in cerebrospinal fluid （CSF） of children with tuberculous meningitis and the significance of the changes. DESIGN： A non-randomized concurrent controlled study. SETTING： Department of Pediatric Internal Medicine, the First Affiliated Hospital of Xinxiang Medical College. PARTICIPANTS： Thirty children with tuberculous meningitis （14 males and 16 females） were selected from the Department of Pediatric Internal Medicine, the First Affiliated Hospital of Xinxiang Medical College from January 2005 to December 2006. Tuberculous meningitis was diagnosed according to their clinical manifestations, the history of close contact with tuberculosis, typical cerebrospinal fluid changes of tuberculous meningitis, positive tuberculosis antibody and effective antituberculosis treatment. There were 30 children （13 males and 17 females） with viral encephalitis, and viral encephalitis was diagnosed according to epidemiological history, clinical manifestations, conventional and biochemical changes of cerebrospinal fluid, and negative bacteriology judgment. Meanwhile, 30 children （13 males and 17 females） without infectious and central nervous system disease were selected as the control group. Informed consent was obtained from the parents of all the enrolled children. METHODS： ①The lumbar puncture operation was implemented immediately to obtain cerebrospinal fluid （3 mL）. The contents of IGF-Ⅱ and IGFBP-3 were detected with immunoradiometric assay. The concentrations of glucose and protein in cerebrospinal fluid were determined with a dry-chemical method. The number of white blood cells was counted by Fushi Method. ②The Pearson correlation analysis was used to analyze the correlation of the contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid with the leucocyte counting and the concentrations of glucose and protein in cerebrospinal fluid. MAIN OUTCOME MEASURES： The contents of IGF- Ⅱ and IGFBP-3 in cerebrospinal fluid, and their correlation with the leucocyte counting and the concentrations of glucose and protein in cerebrospinal fluid. RESULTS： ①Contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid： The contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid in the tuberculous meningitis group were significantly higher than those in the encephalitis virus group and control group （P 〈 0.05）. There was no significant difference in the contents of IGF- Ⅱ and IGFBP-3 in cerebrospinal fluid between the viral encephalitis group and control group （P 〉 0.05）. ②Correlation： The IGF- Ⅱ and IGFBP-3 contents in cerebrospinal fluid were positively correlated with the protein concentration in cerebrospinal fluid （r =0.821, 0.855, P 〈 0.01）, but negatively with the glucose （r =0.742, - 0.605, P 〈 0.01）. CONCLUSION- ①IGFs and IGVBPs are involved in the pathophysiological process of tuberculous meningitis, as well as the glucose and protein metabolism in cerebrospinal fluid. ②The IGF-Ⅱ and IGFBP-3 contents in cerebrospinal fluid can be used as the auxiliary indicators to differentially diagnose tuberculous meningitis and viral enceohalitis.展开更多
BACKGROUND： Human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate si...BACKGROUND： Human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE： To utilize RNA interference （RNAi） technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING： This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS： Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA （siRNA） was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS： C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up： A （2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm） and B （siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES： mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS： All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively （P 〈 0.01）. Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION： siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.展开更多
OBJECTIVE Basic fibroblast growth factor(b FGF)and platelet-derived growth factor(PDGF)produced by hepatocellular carcinoma(HCC)cells are responsible for the cell growth.Accumulating evidence shows that insulin-like g...OBJECTIVE Basic fibroblast growth factor(b FGF)and platelet-derived growth factor(PDGF)produced by hepatocellular carcinoma(HCC)cells are responsible for the cell growth.Accumulating evidence shows that insulin-like growth factor-binding protein-3(IGFBP-3)suppresses HCC cell proliferation in both IGF-dependent and independent manners.The present study is to investigate whether treatment with exogenous IGFBP-3 inhibits bF GF and PDGF production and the cell proliferation of HCC cells.METHODS Cell Counting Kit 8 assay were designed to detect HCC cell proliferation,transcription factor early growth response-1(EGR1)involving in IGFBP-3 regulation of b FGF and PDGF were detected by RT-PCR and Western blot assays.Western blot assay was adopted to detect the IGFBP-3 regulating insulin-like growth factor 1 receptor(IGF-1R)signaling pathway.RESULTS The present study demonstrates that IGFBP-3 suppressed IGF-1-induced b FGF and PDGF expression while it does not affect their expression in the absence of IGF-1.To delineate the underlying mechanism,Western-blot and RT-PCR assays confirmed that the transcription factor early growth response protein 1(EGR1)is involved in IGFBP-3 regulation of b FGF and PDGF.IGFBP-3 inhibition of type 1 insulin-like growth factor receptor(IGF1R),ERK and AKT activation is IGF-1-dependent.Furthermore,transient transfection with constitutively activated AKT or MEK partially blocks the IGFBP-3 inhibition of EGR1,b FGF and PDGF expression.CONCLUSION In conclusion,these findings suggest that IGFBP-3suppresses transcription of EGR1 and its target genes b FGF and PDGF through inhibiting IGF-1-dependent ERK and AKT activation.It demonstrates the importance of IGFBP-3 in the regulation of HCC cell proliferation,suggesting that IGFBP-3 could be a target for the treatment of HCC.展开更多
AIM:To investigate the expression of insulin-like growth factor-1(IGF-1)/insulin-like growth factor-1 receptor(IGF-1R)in colorectal cancer(CRC)tissues and to analyze their correlation with lymphangiogenesis and lympha...AIM:To investigate the expression of insulin-like growth factor-1(IGF-1)/insulin-like growth factor-1 receptor(IGF-1R)in colorectal cancer(CRC)tissues and to analyze their correlation with lymphangiogenesis and lymphatic metastasis.METHODS:Immunohistochemistry was used to evaluate IGF-1 and IGF-1R expression and lymphatic vessel density(LVD)in 40 CRC specimens.The correlation between IGF-1/IGF-1R and LVD was investigated.Effects of IGF-1 on migration and invasion of CRC cells were examined using transwell chamber assays.A LoVo cell xenograft model was established to further detect the role of IGF-1 in CRC lymphangiogenesis in vivo. RESULTS:Elevated IGF-1 and IGF-1R expression in CRC tissues was correlated with lymph node metastasis(r=0.715 and 0.569,respectively,P<0.05)and tumor TNM stage(r=0.731 and 0.609,P<0.05).A higher LVD was also found in CRC tissues and was correlated with lymphatic metastasis(r=0.405,P<0.05).A positive correlation was found between LVD and IGF-1R expression(r=0.437,P<0.05).Transwell assays revealed that IGF-1 increased the migration and invasion of CRC cells.In vivo mouse studies showed that IGF-1 also increased LVD in LoVo cell xenografts.CONCLUSION:IGF-1/IGF-1R signaling induces tumorassociated lymphangiogenesis and contributes to lymphatic metastasis of CRC.展开更多
AIM: To investigate the dynamic features of insulin-like growth factor-I receptor (IGF-IR) expression in rat hepatocarcinogenesis, and the relationship between IGF-IR and hepatocytes malignant transformation at mRNA o...AIM: To investigate the dynamic features of insulin-like growth factor-I receptor (IGF-IR) expression in rat hepatocarcinogenesis, and the relationship between IGF-IR and hepatocytes malignant transformation at mRNA or protein level.METHODS: Hepatoma models were made by inducing with 2-fluorenylacetamide (2-FAA) on male Sprague-Dawley rats. Morphological changes of hepatocytes were observed by pathological Hematoxylin and eosin staining, the dynamic expressions of liver and serum IGF-IR were quantitatively analyzed by an enzyme-linked immunosorbent assay. The distribution of hepatic IGF-IR was located by immunohistochemistry. The fragments of IGF-IR gene were amplified by reverse transcription-polymerase chain reaction, and confirmed by sequencing.RESULTS: Rat hepatocytes after induced by 2-FAA were changed dynamically from granule-like degeneration, precancerous to hepatoma formation with the progressing increasing of hepatic mRNA or IGF-IR expression. The incidences of liver IGF-IR, IGF-IR mRNA, specific IGF-IR concentration (ng/mg wet liver), and serum IGF-IR level (ng/mL) were 0.0%, 0.0%, 0.63 ± 0.17, and 1.33 ± 0.47 in the control; 50.0%, 61.1%, 0.65 ± 0.2, and 1.51 ± 0.46 in the degeneration; 88.9%, 100%, 0.66 ± 0.14, and 1.92 ± 0.29 in the precancerosis; and 100%, 100%, 0.96 ± 0.09, and 2.43 ± 0.57 in the cancerous group, respectively. IGF-IR expression in the cancerous group was significantly higher (P < 0.01) than that in any of other groups at mRNA or protein level. The closely positive IGF-IR relationship was found between livers and sera (r = 0.91, t = 14.222, P < 0.01), respectively.CONCLUSION: IGF-IR expression may participate in rat hepatocarcinogenesis and its abnormality should be an early marker for hepatocytes malignant transformation.展开更多
AIM: To investigate whether the reduction of stem cell factor (SCF) is mediated by decreased endogenous insulin-like growth factor (IGF)-1 in diabetic rat colon smooth muscle. METHODS: Sixteen Sprague-Dawley rats were...AIM: To investigate whether the reduction of stem cell factor (SCF) is mediated by decreased endogenous insulin-like growth factor (IGF)-1 in diabetic rat colon smooth muscle. METHODS: Sixteen Sprague-Dawley rats were randomly divided into two groups: control group and streptozotocin-induced diabetic group. After 8 wk of streptozotocin administration, colonic motility function and contractility of circular muscle strips were measured. The expression of endogenous IGF-1 and SCF was tested in colonic tissues. Colonic smooth muscle cells were cultured from normal adult rats. IGF-1 siRNA transfection was used to investigate whether SCF expression was affected by endogenous IGF-1 expression in smooth muscle cells, and IGF-1 induced SCF expression effects were studied. The effect of high glucose on the expression of endogenous IGF-1 and SCF was also investigated. RESULTS: Diabetic rats showed prolonged colonic transit time (252 ± 16 min vs 168 ± 9 min, P < 0.01) and weakness of circular muscle contraction (0.81 ± 0.09 g vs 2.48 ± 0.23 g, P < 0.01) compared with the control group. Endogenous IGF-1 and SCF protein expression was significantly reduced in the diabetic colonic muscle tissues. IGF-1 and SCF mRNA expression also showed a paralleled reduction in diabetic rats. In the IGF-1 siRNA transfected smooth muscle cells, SCF mRNA and protein expression was significantly decreased. IGF-1 could induce SCF expression in a concentration and time-dependent manner, mainly through the extracellular-signal-regulated kinase 1/2 signal pathway. High glucose inhibited endogenous IGF-1 and SCF expression and the addition of IGF-1 to the medium reversed the SCF expression. CONCLUSION: Myopathy may resolve in colonic motility dysfunction in diabetic rats. Deficiency of endogenous IGF-1 in colonic smooth muscle cells leads to reduction of SCF expression.展开更多
BACKGROUND The digestive tract is the maximal immunizing tissue in the body, and mucosal integrity and functional status of the gut is very important to maintain a healthy organism. Severe infection is one of the most...BACKGROUND The digestive tract is the maximal immunizing tissue in the body, and mucosal integrity and functional status of the gut is very important to maintain a healthy organism. Severe infection is one of the most common causes of gastrointestinal dysfunction, and the pathogenesis is closely related to endotoxemia and intestinal barrier injury. Bifidobacterium is one of the main probiotics in the human body that is involved in digestion, absorption, metabolism, nutrition, and immunity.Bifidobacterium plays an important role in maintaining the intestinal mucosal barrier integrity. This study investigated the protective mechanism of Bifidobacterium during ileal injury in rats.AIM To investigate the effects of Bifidobacterium on cytokine-induced neutrophil chemoattractant(CINC) and insulin-like growth factor 1(IGF-1) in the ileum of rats with endotoxin injury.METHODS Preweaning rats were randomly divided into three groups: Control(group C),model(group E) and treatment(group T). Group E was intraperitoneally injected with lipopolysaccharide(LPS) to create an animal model of intestinal injury.Group T was intragastrically administered Bifidobacterium suspension 7 d before LPS. Group C was intraperitoneally injected with normal saline. The rats were killed at 2, 6 or 12 h after LPS or physiological saline injection to collect ilealtissue samples. The expression of ileal CINC mRNA was evaluated by reverse transcription-polymerase chain reaction(RT-PCR), and expression of ileal IGF-1 protein and mRNA was detected by immunohistochemistry and RT-PCR,respectively.RESULTS The ileum of rats in Group C did not express CINC mRNA, ileums from Group E expressed high levels, which was then significantly decreased in Group T(F =23.947, P < 0.05). There was no significant difference in CINC mRNA expression at different times(F = 0.665, P > 0.05). There was a high level of IGF-1 brown granules in ileal crypts and epithelial cells in Group C, sparse staining in Group E, and dark, dense brown staining in Group T. There was a significant difference between Groups C and E and Groups E and T(P < 0.05). There was no significant difference in IGF-1 protein expression at different times(F = 1.269, P > 0.05). IGF-1 mRNA expression was significantly different among the three groups(P < 0.05),though not at different times(F = 0.086, P > 0.05).CONCLUSION Expression of CINC mRNA increased in the ileum of preweaning rats with endotoxin injury, and exogenous administration of Bifidobacterium reduced CINC m RNA expression. IGF-1 protein and mRNA expression decreased in the ileum of preweaning rats with endotoxin injury, and exogenous administration of Bifidobacterium prevented the decrease in IGF-1 expression. Bifidobacterium may increase IGF-1 expression and enhance intestinal immune barrier function in rats with endotoxin injury.展开更多
AIM:To develop a molecular therapy for pancreatic cancer, the insulin-like growth factor-I (IGF-I) signaling pathway was analyzed.METHODS: Pancreatic cancer cell lines (MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 a...AIM:To develop a molecular therapy for pancreatic cancer, the insulin-like growth factor-I (IGF-I) signaling pathway was analyzed.METHODS: Pancreatic cancer cell lines (MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4) were cultured in media with 10 mL/L fetal bovine serum. Western blotting analysis was performed to clarify the expression of IGF-I receptor (IGF-IR). Picropodophyllin (PPP), a specific inhibitor of IGF-IR, LY294002, a specific inhibitor of phosphatidylinositol3 kinase (PI3K), and PD98059, a specific inhibitor of mitogen-activated protein kinase, were added to the media. After 72 h, a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay was performed to analyze cell proliferation. A wound assay was performed to analyze cell motility with hematoxylin and eosin (HE) staining 48 h after addition of each inhibitor. RESULTS: All cell lines clearly expressed not only IGF-IR but also phosphorylated IGF-IR. PPP significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 36.9% ± 2.4% (mean ± SD), 30.9% ± 5.5%, 23.8% ± 3.9%, 37.1% ± 5.3%, 10.4% ± 4.5%, 52.5% ± 4.5% and 22.6% ± 0.4%, at 2 μmol/L, respectively (P < 0.05). LY294002 significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 44.4% ± 7.6%, 32.9% ± 8.2%, 53.9% ± 8.0%, 52.8% ± 4.0%, 32.3% ± 4.2%, 51.8% ± 4.5%, and 30.6% ± 9.4%, at 50 μmol/L, respectively (P < 0.05). PD98059 did not significantly suppress cell proliferation. PPP at 2 μmol/L suppressed motility of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 3.0% ± 0.2%, 0%, 0%, 2.0% ± 0.1%, 5.0% ± 0.2%, 3.0% ± 0.1%, and 5.0% ± 0.2%, respectively (P < 0.05). LY294002 at 50 μmol/L suppressed motility of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 to 3.0% ± 0.2%, 0%, 3.0% ± 0.2%, 0%, 0%, 0% and 3% ± 0.1%, respectively (P < 0.05). PD980509 at 20 μmol/L did not suppress motility. Cells were observed by microscopy to analyze the morphological changes induced by the inhibitors. Cells in medium treated with 2 μmol/L PPP or 50 μmol/L LY294002 had pyknotic nuclei, whereas those in medium with 20 μmol/L PD98059 did not show apoptosis.CONCLUSION: IGF-IR and PI3K are good candidates for molecular therapy of pancreatic cancer.展开更多
AIM: To investigate the effect of microR NA on insulinlike growth factor binding protein-3(IGFBP-3) and hence on insulin-like growth factor-Ⅱ(IGF-Ⅱ) bioavailability in hepatocellular carcinoma(HCC).METHODS: Bioinfor...AIM: To investigate the effect of microR NA on insulinlike growth factor binding protein-3(IGFBP-3) and hence on insulin-like growth factor-Ⅱ(IGF-Ⅱ) bioavailability in hepatocellular carcinoma(HCC).METHODS: Bioinformatic analysis was performed using microrna.org, DIANA lab and Segal lab softwares. Total RNA was extracted from 23 HCC and 10 healthy liver tissues using mir Vana mi RNA Isolation Kit. microR NA-17-5p(miR-17-5p) expression was mimicked and antagonized in Hu H-7 cell lines using Hi Per Fect Transfection Reagent, then total RNA was extracted using Biozol reagent then reverse transcribed into cD NA followed by quantification of mi R-17-5p and IGFBP-3 expression using Taq Man real-time quantitative PCR. Luciferase reporter assay was performed to validate the binding of miR-17-5p to the 3'UTR of IGFBP-3. Free IGF-Ⅱ protein was measured in transfected Hu H-7 cells using IGF-Ⅱ ELISA kit. RESULTS: Bioinformatic analysis revealed IGFBP-3 as a potential target for miR-17-5p. Screening of miR-17-5p and IGFBP-3 revealed a moderate negative correlation in HCC patients, where mi R-17-5p was extensively underexpressed in HCC tissues(P = 0.0012), while IGFBP-3 showed significant upregulation in the same set of patients(P = 0.0041) compared to healthy donors. Forcing mi R-17-5p expression in Hu H-7 cell lines showed a significant downregulation of IGFBP-3 mR NA expression(P = 0.0267) and a significant increase in free IGF-Ⅱ protein(P = 0.0339) compared to mock untransfected cells using unpaired t-test. Luciferase assay validated IGFBP-3 as a direct target of mi R-17-5p; luciferase activity was inhibited by 27.5% in cells co-transfected with miR-17-5p mimics and the construct harboring the wild-type binding region 2 of IGFBP-3 compared to cells transfected with this construct alone(P = 0.0474).CONCLUSION: These data suggest that regulating IGF-Ⅱ bioavailability and hence HCC progression can be achieved through targeting IGFBP-3 via manipulating the expression of miR NAs.展开更多
BACKGROUND Studies have shown that insulin-like growth factor 2 mRNA-binding protein 1(IGF2BP1)plays critical roles in the genesis and development of human cancers.AIM To investigate the clinical significance and role...BACKGROUND Studies have shown that insulin-like growth factor 2 mRNA-binding protein 1(IGF2BP1)plays critical roles in the genesis and development of human cancers.AIM To investigate the clinical significance and role of IGF2BP1 in pancreatic cancer.METHODS Expression levels of IGF2BP1 and microRNA-494(miR-494)were mined based on Gene Expression Omnibus datasets and validated in both clinical samples and cell lines by quantitative real-time polymerase chain reaction and Western blot.The relationship between IGF2BP1 expression and clinicopathological factors of pancreatic cancer patients was analyzed.The effect and mechanism of IGF2BP1 on pancreatic cancer cell proliferation were investigated in vitro and in vivo.Analyses were performed to explore underlying mechanisms of IGF2BP1 upregulation in pancreatic cancer and assays were carried out to verify the posttranscriptional regulation of IGF2BP1 by miR-494.RESULTS We found that IGF2BP1 was upregulated and associated with a poor prognosis in pancreatic cancer patients.We showed that downregulation of IGF2BP1 inhibited pancreatic cancer cell growth in vitro and in vivo via the AKT signaling pathway.Mechanistically,we showed that the frequent upregulation of IGF2BP1 was attributed to the downregulation of miR-494 expression in pancreatic cancer.Furthermore,we discovered that reexpression of miR-494 could partially abrogate the oncogenic role of IGF2BP1.CONCLUSION Our results revealed that upregulated IGF2BP1 promotes the proliferation of pancreatic cancer cells via the AKT signaling pathway and confirmed that the activation of IGF2BP1 is partly due to the silencing of miR-494.展开更多
AIM:To determine the contributions of insulin-like growth factor 1 (IGF-1),cytokines and liver disease severity to bone mineral density in patients pre-transplantation.METHODS:Serum IGF-1,tumor necrosis factor-α (TNF...AIM:To determine the contributions of insulin-like growth factor 1 (IGF-1),cytokines and liver disease severity to bone mineral density in patients pre-transplantation.METHODS:Serum IGF-1,tumor necrosis factor-α (TNFα) and interleukin 6 (IL-6) were measured and the Model for End-Stage Liver Disease (MELD) score calculated in 121 adult patients referred to a single centre for liver transplantation.Bone mineral density (BMD) of the lumbar spine and femoral neck were assessed via dual energy X-ray absorptiometry.Demographics,liver disease etiology,medication use and relevant biochemistry were recorded.RESULTS:A total of 117 subjects were included,with low BMD seen in 68.6%,irrespective of disease etiol-ogy.In multivariable analysis,low body mass index (BMI),increased bone turnover and low IGF-1 were independent predictors of low spinal bone density.At the hip,BMI,IGF-1 and vitamin D status were predictive.Despite prevalent elevations of TNFα and IL-6,levels did not correlate with degree of bone loss.The MELD score failed to predict low BMD in this pre-transplant population.CONCLUSION:Osteopenia/osteoporosis is common in advanced liver disease.Low serum IGF-1 is weakly predictive but serum cytokine and MELD score fail to predict the severity of bone disease.展开更多
INTRODUCTIONInsulin-like growth factor Ⅱ(IGF-Ⅱ) is a mitogenic peptide of 74 kD and is mostly synthesized in fetal liver tissue .IGF-Ⅱ is believed to play an important role in fetal growth and development and is in...INTRODUCTIONInsulin-like growth factor Ⅱ(IGF-Ⅱ) is a mitogenic peptide of 74 kD and is mostly synthesized in fetal liver tissue .IGF-Ⅱ is believed to play an important role in fetal growth and development and is involved in cellular proliferation and differentiation[1-5]. Recently ,several researchers have reported increased expression of the IGF-Ⅱgene in human hepatocellular carcinoma (HCC) and adjacent non-cancerous liver tissues [6-10].展开更多
Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured...Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured. A transdifferentiation model of primary rat lung fibroblasts was induced by free silica. Levels of a-SMA protein, IGF-liR protein and mRNA were measured by immunocytochemistry, Western blot and RT-PCR, respectively. Lung fibroblasts were treated with Wortmannin. Results The expression levels of a-SMA concentration and decreased after Wortmann and IGF-IIR increased with the increasing free silica n was used. Conclusion The IGF-IIR plays an important role in free silica-induced transdifferentiation of primary rat lung fibroblasts.展开更多
文摘[Objective] The research aimed to enhance culture efficiencies of oocyte and embryo of goat in vitro and to explore serum-free culture system in vitro.[Method] At present,the conventional solutions of oocyte maturation and embryo development in vitro were always added into 1% ITS(Insulin-transferrin-selenium) or using 1% ITS to replace FBS in 2 kinds culture solutions for conducting in vitro cultures of goat oocyte and parthenogenetic embryo.The influences of ITS on their developments were detected.[Result] ITS in maturation liquid of oocytes could not increase oocytes maturation rate but significantly increased blastocyst rate (58.06% vs. 48.19%)of parthenogenetic embryo.If FBS in maturation liquid of oocytes was replaced by ITS, the maturation rate, cleavage rate and blastocyst rate were basically unchanged.Adding ITS into embryo medium could increase blastocyst rate (68.30% vs. 56.82%)of parthenogenetic embryo of goat.If FBS in embryo medium was replaced by ITS,the cleavage rate didn’t change basically,while the blastocyst rate in ITS was obviously lower than that in FBS group(42.33% vs.56.82%).[Conclusion] ITS could promote maturation of oocyte in vitro and early embryonic development, in addition,ITS could replace serum in maturation medium of oocyte as serum-free culture system for conducting relevant researches.
文摘The insulin-like growth factor(IGF) signaling path-way is an important pathway in the process of hepa-tocarcinogenesis,and the IGF network is clearly dysregulated in many cancers and developmental abnormalities.In hepatocellular carcinoma(HCC),only a minority of patients are eligible for curative treatments,such as tumor resection or liver transplant.Unfortunately,there is a high recurrence of HCC after surgical tumor removal.Recent research efforts have focused on targeting IGF axis members in an attempt to find therapeutic options for many health problems.In this review,we shed lights on the regulation of members of the IGF axis,mainly by micro RNAs in HCC.Micro RNAs in HCC attempt to halt the aberrant expression of the IGF network,and a single micro RNA can have multiple downstream targets in one or more signaling pathways.Targeting micro RNAs is a relatively new approach for identifying an efficient radical cure for HCC.
基金sponsored by the Natural Science Foundation of Hebei Province,H2012406018,H2013406096a grant from Hebei Province Department of Education,No.2006301
文摘Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats.
文摘[ Objedive] This study was aimed to determine the single nucleotide polymorphisms （SNPs） of IGF-I gene in two breeds, Wanxi white goose and Langde goose. [ Method] Two pair of primers was designed based on chicken and porcine genomic sequence to amplify the 5＇ regulatory region of IGF-I, and the sequence was determined and analyzed. [ Result] A total of four SNPs were identified in this region by PCR-SSCP meth- od, that is, A to T at 26 nt, A to G at 215 nt, A to G at 314 nt, and A to T at 325 nt. [ Conclusioa] The two breeds ,wanxi white geese and Langde geese, agree with Hardy-weinberg equilibrium with respect to these SNPS.
基金a grant from the New Century Talents Supporting Scheme in Universities of Henan Province
文摘BACKGROUND： Recent studies have found that insulin-like growth factors （IGFs） and insulin-like growth factor binding protein-3 （IGFBP-3） have stronger neurotrophic and neuroprotective effects. But whether their levels in cerebrospinal fluid could be used as an auxiliary indicator in differentially diagnosing tuberculous meningitis and viral encephalitis is not yet clear. OBJECTIVE： To explore the changes of insulin-like growth factor-Ⅱ （IGF-Ⅱ ） and IGFBP-3 in cerebrospinal fluid （CSF） of children with tuberculous meningitis and the significance of the changes. DESIGN： A non-randomized concurrent controlled study. SETTING： Department of Pediatric Internal Medicine, the First Affiliated Hospital of Xinxiang Medical College. PARTICIPANTS： Thirty children with tuberculous meningitis （14 males and 16 females） were selected from the Department of Pediatric Internal Medicine, the First Affiliated Hospital of Xinxiang Medical College from January 2005 to December 2006. Tuberculous meningitis was diagnosed according to their clinical manifestations, the history of close contact with tuberculosis, typical cerebrospinal fluid changes of tuberculous meningitis, positive tuberculosis antibody and effective antituberculosis treatment. There were 30 children （13 males and 17 females） with viral encephalitis, and viral encephalitis was diagnosed according to epidemiological history, clinical manifestations, conventional and biochemical changes of cerebrospinal fluid, and negative bacteriology judgment. Meanwhile, 30 children （13 males and 17 females） without infectious and central nervous system disease were selected as the control group. Informed consent was obtained from the parents of all the enrolled children. METHODS： ①The lumbar puncture operation was implemented immediately to obtain cerebrospinal fluid （3 mL）. The contents of IGF-Ⅱ and IGFBP-3 were detected with immunoradiometric assay. The concentrations of glucose and protein in cerebrospinal fluid were determined with a dry-chemical method. The number of white blood cells was counted by Fushi Method. ②The Pearson correlation analysis was used to analyze the correlation of the contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid with the leucocyte counting and the concentrations of glucose and protein in cerebrospinal fluid. MAIN OUTCOME MEASURES： The contents of IGF- Ⅱ and IGFBP-3 in cerebrospinal fluid, and their correlation with the leucocyte counting and the concentrations of glucose and protein in cerebrospinal fluid. RESULTS： ①Contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid： The contents of IGF-Ⅱ and IGFBP-3 in cerebrospinal fluid in the tuberculous meningitis group were significantly higher than those in the encephalitis virus group and control group （P 〈 0.05）. There was no significant difference in the contents of IGF- Ⅱ and IGFBP-3 in cerebrospinal fluid between the viral encephalitis group and control group （P 〉 0.05）. ②Correlation： The IGF- Ⅱ and IGFBP-3 contents in cerebrospinal fluid were positively correlated with the protein concentration in cerebrospinal fluid （r =0.821, 0.855, P 〈 0.01）, but negatively with the glucose （r =0.742, - 0.605, P 〈 0.01）. CONCLUSION- ①IGFs and IGVBPs are involved in the pathophysiological process of tuberculous meningitis, as well as the glucose and protein metabolism in cerebrospinal fluid. ②The IGF-Ⅱ and IGFBP-3 contents in cerebrospinal fluid can be used as the auxiliary indicators to differentially diagnose tuberculous meningitis and viral enceohalitis.
基金the National Natural Science Foundation of China,No.30371459Science and Technology Development Fund of Shanghai,No.034047
文摘BACKGROUND： Human gliomas are more likely to express basic fibroblast growth factor-2 （FGF-2） insulin-like growth factor-1（IGF-1）, and IGF-1 receptor （IGF-1R） than normal brain tissue. These factors activate signal transduction systems of Ras/MAPK and PI3K/Akl, which promote glioma growth. OBJECTIVE： To utilize RNA interference （RNAi） technique to down-regulate FGF-2, IGF-1, and IGF-1R gene expression, and to investigate the effects of these genes on rat C6 glioma cells, as well as the feasibility of RNAi for treating glioma. DESIGN, TIME AND SETTING： This neurooncological, randomized, controlled, in vivo and in vitro experiment, which used RNAi methodology, was performed at the Laboratory of Molecular Biology, Institute of Biochemistry, Chinese Academy of Sciences between August 2005 and February 2008. MATERIALS： Rat C6 cell lines were purchased from Shanghai Institute of Cellular Biology Affiliated to Chinese Academy of Sciences. Small interfering RNA （siRNA） was synthesized by Shanghai GenePharma. Anti-IGF-1, anti-IGF-1R, anti-FGF-2, anti-mouse and anti-rabbit IgG G1-HRP antibodies were provided by Santa Cruz Biotechnology, USA. Four to six week-old BALB/c nude mice were purchased from the Laboratory Animal Center, Chinese Academy of Sciences. METHODS： C6 glioma cells were transfected with siRNA, which was chemically synthesized in vitro to correspond to endogenous FGF-2, IGF-1, and IGF-1R genes. The inhibition ratio of targeting mRNA expression was detected by semiquantitative RT-PCR, and protein expression was determined by Western blot analysis. C6 glioma cell proliferation was observed using a growth curve C6 glioma cell apoptosis rate and cell cycle were detected by flow cytometry. C6 glioma cell growth regression was observed by transwell migration assay. In addition, nude mouse subcutaneous tumor models were used in this study. For studying the anti-tumor effects of IGF-1 and IGF-1R siRNA, two blank control groups, with six mice each, were set up： A （2.5 μg siRNA was injected one week after C6 cells were inoculated, Le., when tumor volume reached 8 mm × 8 mm） and B （siRNA was injected at the same time with C6 cells were inoculated. To study the effects of FGF-2 siRNA, the groups consisted of a blank control group, negative control group, 2.6 μg siRNA group, 4 μg siRNA group, and 5.3 μg siRNA group, with six mice each. MAIN OUTCOME MEASURES： mRNA and protein inhibition ratio of FGF-2, IGF-1, and IGF-1 R; C6 glioma cell proliferation, apoptosis, and cycle growth arrest; C6 glioma cell growth regression and subcutaneous tumorigenicity rates. RESULTS： All siRNA constructs proved to be effective. After 48 hours, transfection of 200 nmol/L siRNA resulted in a FGF-2 or IGF-1R gene inhibition ratio 〉 80% and an IGF-1 gene inhibition ratio of approximately 70%. Protein expression levels for FGF-2, IGF-1, and IGF-1R decreased in a dose-dependent manner following siRNA transfection, with an inhibition rate 〉 85%, 60%, and 50%, respectively. C6 glioma cell proliferation and apoptosis rates increased in proportion to siRNA. The apoptosis rate of C6 glioma cells induced by FGF-2, IGF-1, and IGF-1R siRNA was 39.96%, 15.07% and 22.47%, respectively （P 〈 0.01）. Transfection of 200 nmol/L IGF or IGF-1R siRNA for 48 hours suppressed C6 glioma cell migration. At 30 days after intratumoral injection of 2.6, 4, and 5.3 tJg FGF-2 siRNA, tumor growth regression rate of FGF-2 siRNA was 56%, 67%, and 86%, respectively. The tumor growth regression rate was 71.88% and 45.71%, respectively, when IGF-1 or IGF-1R siRNA was intratumorally injected 1 week after C6 glioma cell transplantation. When IGF-1 or IGF-1 R siRNA was intratumorally injected during C6 glioma cell transplantation, the tumor growth regression rate was 78.13% and 74.29%, respectively. CONCLUSION： siRNA transfection downregulated gene expression of FGF-2, IGF-1, and IGF-1R In addition, siRNA treatment markedly suppressed glioma cell proliferation, growth, and migration, and concomitantly reduced subcutaneous tumorigenicity.
基金supported by National Natural Science Foundation of China(81502123 and81330081)Natural Science Foundation of Anhui Province(1308085QH130)Anhui Province Nature Science Foundation in University(KJ2014A119)
文摘OBJECTIVE Basic fibroblast growth factor(b FGF)and platelet-derived growth factor(PDGF)produced by hepatocellular carcinoma(HCC)cells are responsible for the cell growth.Accumulating evidence shows that insulin-like growth factor-binding protein-3(IGFBP-3)suppresses HCC cell proliferation in both IGF-dependent and independent manners.The present study is to investigate whether treatment with exogenous IGFBP-3 inhibits bF GF and PDGF production and the cell proliferation of HCC cells.METHODS Cell Counting Kit 8 assay were designed to detect HCC cell proliferation,transcription factor early growth response-1(EGR1)involving in IGFBP-3 regulation of b FGF and PDGF were detected by RT-PCR and Western blot assays.Western blot assay was adopted to detect the IGFBP-3 regulating insulin-like growth factor 1 receptor(IGF-1R)signaling pathway.RESULTS The present study demonstrates that IGFBP-3 suppressed IGF-1-induced b FGF and PDGF expression while it does not affect their expression in the absence of IGF-1.To delineate the underlying mechanism,Western-blot and RT-PCR assays confirmed that the transcription factor early growth response protein 1(EGR1)is involved in IGFBP-3 regulation of b FGF and PDGF.IGFBP-3 inhibition of type 1 insulin-like growth factor receptor(IGF1R),ERK and AKT activation is IGF-1-dependent.Furthermore,transient transfection with constitutively activated AKT or MEK partially blocks the IGFBP-3 inhibition of EGR1,b FGF and PDGF expression.CONCLUSION In conclusion,these findings suggest that IGFBP-3suppresses transcription of EGR1 and its target genes b FGF and PDGF through inhibiting IGF-1-dependent ERK and AKT activation.It demonstrates the importance of IGFBP-3 in the regulation of HCC cell proliferation,suggesting that IGFBP-3 could be a target for the treatment of HCC.
基金Supported by Technological Research Project for Public Welfare from Science and Technology Department of Zhejiang Province,No.2010C33099
文摘AIM:To investigate the expression of insulin-like growth factor-1(IGF-1)/insulin-like growth factor-1 receptor(IGF-1R)in colorectal cancer(CRC)tissues and to analyze their correlation with lymphangiogenesis and lymphatic metastasis.METHODS:Immunohistochemistry was used to evaluate IGF-1 and IGF-1R expression and lymphatic vessel density(LVD)in 40 CRC specimens.The correlation between IGF-1/IGF-1R and LVD was investigated.Effects of IGF-1 on migration and invasion of CRC cells were examined using transwell chamber assays.A LoVo cell xenograft model was established to further detect the role of IGF-1 in CRC lymphangiogenesis in vivo. RESULTS:Elevated IGF-1 and IGF-1R expression in CRC tissues was correlated with lymph node metastasis(r=0.715 and 0.569,respectively,P<0.05)and tumor TNM stage(r=0.731 and 0.609,P<0.05).A higher LVD was also found in CRC tissues and was correlated with lymphatic metastasis(r=0.405,P<0.05).A positive correlation was found between LVD and IGF-1R expression(r=0.437,P<0.05).Transwell assays revealed that IGF-1 increased the migration and invasion of CRC cells.In vivo mouse studies showed that IGF-1 also increased LVD in LoVo cell xenografts.CONCLUSION:IGF-1/IGF-1R signaling induces tumorassociated lymphangiogenesis and contributes to lymphatic metastasis of CRC.
基金Supported by The Society Development of Nantong,HS2012039Jiangsu Health Projects,BL2012053,K201102the Priority Academic Program Development of Jiangsu,and the International S and T Cooperation Program,2013DFA32150 of China
文摘AIM: To investigate the dynamic features of insulin-like growth factor-I receptor (IGF-IR) expression in rat hepatocarcinogenesis, and the relationship between IGF-IR and hepatocytes malignant transformation at mRNA or protein level.METHODS: Hepatoma models were made by inducing with 2-fluorenylacetamide (2-FAA) on male Sprague-Dawley rats. Morphological changes of hepatocytes were observed by pathological Hematoxylin and eosin staining, the dynamic expressions of liver and serum IGF-IR were quantitatively analyzed by an enzyme-linked immunosorbent assay. The distribution of hepatic IGF-IR was located by immunohistochemistry. The fragments of IGF-IR gene were amplified by reverse transcription-polymerase chain reaction, and confirmed by sequencing.RESULTS: Rat hepatocytes after induced by 2-FAA were changed dynamically from granule-like degeneration, precancerous to hepatoma formation with the progressing increasing of hepatic mRNA or IGF-IR expression. The incidences of liver IGF-IR, IGF-IR mRNA, specific IGF-IR concentration (ng/mg wet liver), and serum IGF-IR level (ng/mL) were 0.0%, 0.0%, 0.63 ± 0.17, and 1.33 ± 0.47 in the control; 50.0%, 61.1%, 0.65 ± 0.2, and 1.51 ± 0.46 in the degeneration; 88.9%, 100%, 0.66 ± 0.14, and 1.92 ± 0.29 in the precancerosis; and 100%, 100%, 0.96 ± 0.09, and 2.43 ± 0.57 in the cancerous group, respectively. IGF-IR expression in the cancerous group was significantly higher (P < 0.01) than that in any of other groups at mRNA or protein level. The closely positive IGF-IR relationship was found between livers and sera (r = 0.91, t = 14.222, P < 0.01), respectively.CONCLUSION: IGF-IR expression may participate in rat hepatocarcinogenesis and its abnormality should be an early marker for hepatocytes malignant transformation.
基金Supported by The National Natural Science Foundation of China, No. 30971354The International Cooperation Project of Jiangsu Province Department of Health, No. SBZ201100103The Graduate Innovation Foundation of Jiangsu Province, China,No. CXZZ11_0704
文摘AIM: To investigate whether the reduction of stem cell factor (SCF) is mediated by decreased endogenous insulin-like growth factor (IGF)-1 in diabetic rat colon smooth muscle. METHODS: Sixteen Sprague-Dawley rats were randomly divided into two groups: control group and streptozotocin-induced diabetic group. After 8 wk of streptozotocin administration, colonic motility function and contractility of circular muscle strips were measured. The expression of endogenous IGF-1 and SCF was tested in colonic tissues. Colonic smooth muscle cells were cultured from normal adult rats. IGF-1 siRNA transfection was used to investigate whether SCF expression was affected by endogenous IGF-1 expression in smooth muscle cells, and IGF-1 induced SCF expression effects were studied. The effect of high glucose on the expression of endogenous IGF-1 and SCF was also investigated. RESULTS: Diabetic rats showed prolonged colonic transit time (252 ± 16 min vs 168 ± 9 min, P < 0.01) and weakness of circular muscle contraction (0.81 ± 0.09 g vs 2.48 ± 0.23 g, P < 0.01) compared with the control group. Endogenous IGF-1 and SCF protein expression was significantly reduced in the diabetic colonic muscle tissues. IGF-1 and SCF mRNA expression also showed a paralleled reduction in diabetic rats. In the IGF-1 siRNA transfected smooth muscle cells, SCF mRNA and protein expression was significantly decreased. IGF-1 could induce SCF expression in a concentration and time-dependent manner, mainly through the extracellular-signal-regulated kinase 1/2 signal pathway. High glucose inhibited endogenous IGF-1 and SCF expression and the addition of IGF-1 to the medium reversed the SCF expression. CONCLUSION: Myopathy may resolve in colonic motility dysfunction in diabetic rats. Deficiency of endogenous IGF-1 in colonic smooth muscle cells leads to reduction of SCF expression.
基金Supported by the Education Department of Heilongjiang Province,China,No.11521124
文摘BACKGROUND The digestive tract is the maximal immunizing tissue in the body, and mucosal integrity and functional status of the gut is very important to maintain a healthy organism. Severe infection is one of the most common causes of gastrointestinal dysfunction, and the pathogenesis is closely related to endotoxemia and intestinal barrier injury. Bifidobacterium is one of the main probiotics in the human body that is involved in digestion, absorption, metabolism, nutrition, and immunity.Bifidobacterium plays an important role in maintaining the intestinal mucosal barrier integrity. This study investigated the protective mechanism of Bifidobacterium during ileal injury in rats.AIM To investigate the effects of Bifidobacterium on cytokine-induced neutrophil chemoattractant(CINC) and insulin-like growth factor 1(IGF-1) in the ileum of rats with endotoxin injury.METHODS Preweaning rats were randomly divided into three groups: Control(group C),model(group E) and treatment(group T). Group E was intraperitoneally injected with lipopolysaccharide(LPS) to create an animal model of intestinal injury.Group T was intragastrically administered Bifidobacterium suspension 7 d before LPS. Group C was intraperitoneally injected with normal saline. The rats were killed at 2, 6 or 12 h after LPS or physiological saline injection to collect ilealtissue samples. The expression of ileal CINC mRNA was evaluated by reverse transcription-polymerase chain reaction(RT-PCR), and expression of ileal IGF-1 protein and mRNA was detected by immunohistochemistry and RT-PCR,respectively.RESULTS The ileum of rats in Group C did not express CINC mRNA, ileums from Group E expressed high levels, which was then significantly decreased in Group T(F =23.947, P < 0.05). There was no significant difference in CINC mRNA expression at different times(F = 0.665, P > 0.05). There was a high level of IGF-1 brown granules in ileal crypts and epithelial cells in Group C, sparse staining in Group E, and dark, dense brown staining in Group T. There was a significant difference between Groups C and E and Groups E and T(P < 0.05). There was no significant difference in IGF-1 protein expression at different times(F = 1.269, P > 0.05). IGF-1 mRNA expression was significantly different among the three groups(P < 0.05),though not at different times(F = 0.086, P > 0.05).CONCLUSION Expression of CINC mRNA increased in the ileum of preweaning rats with endotoxin injury, and exogenous administration of Bifidobacterium reduced CINC m RNA expression. IGF-1 protein and mRNA expression decreased in the ileum of preweaning rats with endotoxin injury, and exogenous administration of Bifidobacterium prevented the decrease in IGF-1 expression. Bifidobacterium may increase IGF-1 expression and enhance intestinal immune barrier function in rats with endotoxin injury.
文摘AIM:To develop a molecular therapy for pancreatic cancer, the insulin-like growth factor-I (IGF-I) signaling pathway was analyzed.METHODS: Pancreatic cancer cell lines (MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4) were cultured in media with 10 mL/L fetal bovine serum. Western blotting analysis was performed to clarify the expression of IGF-I receptor (IGF-IR). Picropodophyllin (PPP), a specific inhibitor of IGF-IR, LY294002, a specific inhibitor of phosphatidylinositol3 kinase (PI3K), and PD98059, a specific inhibitor of mitogen-activated protein kinase, were added to the media. After 72 h, a 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt (MTS) assay was performed to analyze cell proliferation. A wound assay was performed to analyze cell motility with hematoxylin and eosin (HE) staining 48 h after addition of each inhibitor. RESULTS: All cell lines clearly expressed not only IGF-IR but also phosphorylated IGF-IR. PPP significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 36.9% ± 2.4% (mean ± SD), 30.9% ± 5.5%, 23.8% ± 3.9%, 37.1% ± 5.3%, 10.4% ± 4.5%, 52.5% ± 4.5% and 22.6% ± 0.4%, at 2 μmol/L, respectively (P < 0.05). LY294002 significantly suppressed proliferation of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 44.4% ± 7.6%, 32.9% ± 8.2%, 53.9% ± 8.0%, 52.8% ± 4.0%, 32.3% ± 4.2%, 51.8% ± 4.5%, and 30.6% ± 9.4%, at 50 μmol/L, respectively (P < 0.05). PD98059 did not significantly suppress cell proliferation. PPP at 2 μmol/L suppressed motility of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 cells to 3.0% ± 0.2%, 0%, 0%, 2.0% ± 0.1%, 5.0% ± 0.2%, 3.0% ± 0.1%, and 5.0% ± 0.2%, respectively (P < 0.05). LY294002 at 50 μmol/L suppressed motility of MIA-Paca2, NOR-P1, PANC-1, PK-45H, PK-1, PK-59 and KP-4 to 3.0% ± 0.2%, 0%, 3.0% ± 0.2%, 0%, 0%, 0% and 3% ± 0.1%, respectively (P < 0.05). PD980509 at 20 μmol/L did not suppress motility. Cells were observed by microscopy to analyze the morphological changes induced by the inhibitors. Cells in medium treated with 2 μmol/L PPP or 50 μmol/L LY294002 had pyknotic nuclei, whereas those in medium with 20 μmol/L PD98059 did not show apoptosis.CONCLUSION: IGF-IR and PI3K are good candidates for molecular therapy of pancreatic cancer.
文摘AIM: To investigate the effect of microR NA on insulinlike growth factor binding protein-3(IGFBP-3) and hence on insulin-like growth factor-Ⅱ(IGF-Ⅱ) bioavailability in hepatocellular carcinoma(HCC).METHODS: Bioinformatic analysis was performed using microrna.org, DIANA lab and Segal lab softwares. Total RNA was extracted from 23 HCC and 10 healthy liver tissues using mir Vana mi RNA Isolation Kit. microR NA-17-5p(miR-17-5p) expression was mimicked and antagonized in Hu H-7 cell lines using Hi Per Fect Transfection Reagent, then total RNA was extracted using Biozol reagent then reverse transcribed into cD NA followed by quantification of mi R-17-5p and IGFBP-3 expression using Taq Man real-time quantitative PCR. Luciferase reporter assay was performed to validate the binding of miR-17-5p to the 3'UTR of IGFBP-3. Free IGF-Ⅱ protein was measured in transfected Hu H-7 cells using IGF-Ⅱ ELISA kit. RESULTS: Bioinformatic analysis revealed IGFBP-3 as a potential target for miR-17-5p. Screening of miR-17-5p and IGFBP-3 revealed a moderate negative correlation in HCC patients, where mi R-17-5p was extensively underexpressed in HCC tissues(P = 0.0012), while IGFBP-3 showed significant upregulation in the same set of patients(P = 0.0041) compared to healthy donors. Forcing mi R-17-5p expression in Hu H-7 cell lines showed a significant downregulation of IGFBP-3 mR NA expression(P = 0.0267) and a significant increase in free IGF-Ⅱ protein(P = 0.0339) compared to mock untransfected cells using unpaired t-test. Luciferase assay validated IGFBP-3 as a direct target of mi R-17-5p; luciferase activity was inhibited by 27.5% in cells co-transfected with miR-17-5p mimics and the construct harboring the wild-type binding region 2 of IGFBP-3 compared to cells transfected with this construct alone(P = 0.0474).CONCLUSION: These data suggest that regulating IGF-Ⅱ bioavailability and hence HCC progression can be achieved through targeting IGFBP-3 via manipulating the expression of miR NAs.
基金Supported by the National Natural Science Foundation of China,No.61802350
文摘BACKGROUND Studies have shown that insulin-like growth factor 2 mRNA-binding protein 1(IGF2BP1)plays critical roles in the genesis and development of human cancers.AIM To investigate the clinical significance and role of IGF2BP1 in pancreatic cancer.METHODS Expression levels of IGF2BP1 and microRNA-494(miR-494)were mined based on Gene Expression Omnibus datasets and validated in both clinical samples and cell lines by quantitative real-time polymerase chain reaction and Western blot.The relationship between IGF2BP1 expression and clinicopathological factors of pancreatic cancer patients was analyzed.The effect and mechanism of IGF2BP1 on pancreatic cancer cell proliferation were investigated in vitro and in vivo.Analyses were performed to explore underlying mechanisms of IGF2BP1 upregulation in pancreatic cancer and assays were carried out to verify the posttranscriptional regulation of IGF2BP1 by miR-494.RESULTS We found that IGF2BP1 was upregulated and associated with a poor prognosis in pancreatic cancer patients.We showed that downregulation of IGF2BP1 inhibited pancreatic cancer cell growth in vitro and in vivo via the AKT signaling pathway.Mechanistically,we showed that the frequent upregulation of IGF2BP1 was attributed to the downregulation of miR-494 expression in pancreatic cancer.Furthermore,we discovered that reexpression of miR-494 could partially abrogate the oncogenic role of IGF2BP1.CONCLUSION Our results revealed that upregulated IGF2BP1 promotes the proliferation of pancreatic cancer cells via the AKT signaling pathway and confirmed that the activation of IGF2BP1 is partly due to the silencing of miR-494.
基金Supported by the Transplant Program of the University of Alberta Hospital
文摘AIM:To determine the contributions of insulin-like growth factor 1 (IGF-1),cytokines and liver disease severity to bone mineral density in patients pre-transplantation.METHODS:Serum IGF-1,tumor necrosis factor-α (TNFα) and interleukin 6 (IL-6) were measured and the Model for End-Stage Liver Disease (MELD) score calculated in 121 adult patients referred to a single centre for liver transplantation.Bone mineral density (BMD) of the lumbar spine and femoral neck were assessed via dual energy X-ray absorptiometry.Demographics,liver disease etiology,medication use and relevant biochemistry were recorded.RESULTS:A total of 117 subjects were included,with low BMD seen in 68.6%,irrespective of disease etiol-ogy.In multivariable analysis,low body mass index (BMI),increased bone turnover and low IGF-1 were independent predictors of low spinal bone density.At the hip,BMI,IGF-1 and vitamin D status were predictive.Despite prevalent elevations of TNFα and IL-6,levels did not correlate with degree of bone loss.The MELD score failed to predict low BMD in this pre-transplant population.CONCLUSION:Osteopenia/osteoporosis is common in advanced liver disease.Low serum IGF-1 is weakly predictive but serum cytokine and MELD score fail to predict the severity of bone disease.
基金Project supported by the National Nature Science Foundation of China,No.39470774
文摘INTRODUCTIONInsulin-like growth factor Ⅱ(IGF-Ⅱ) is a mitogenic peptide of 74 kD and is mostly synthesized in fetal liver tissue .IGF-Ⅱ is believed to play an important role in fetal growth and development and is involved in cellular proliferation and differentiation[1-5]. Recently ,several researchers have reported increased expression of the IGF-Ⅱgene in human hepatocellular carcinoma (HCC) and adjacent non-cancerous liver tissues [6-10].
基金supported by the Research Fund from theNational Natural Science Foundation of China(#81102109)
文摘Objective To study the role of insulin-like growth factor II receptor in free silica-induced transdifferentiation of primary rat lung fibroblasts Methods Rat lung fibroblasts and rat alveolar macrophages were cultured. A transdifferentiation model of primary rat lung fibroblasts was induced by free silica. Levels of a-SMA protein, IGF-liR protein and mRNA were measured by immunocytochemistry, Western blot and RT-PCR, respectively. Lung fibroblasts were treated with Wortmannin. Results The expression levels of a-SMA concentration and decreased after Wortmann and IGF-IIR increased with the increasing free silica n was used. Conclusion The IGF-IIR plays an important role in free silica-induced transdifferentiation of primary rat lung fibroblasts.
