west china medical publishers
Keyword
  • Title
  • Author
  • Keyword
  • Abstract
Advance search
Advance search

Search

find Keyword "Insulin-like growth factor" 31 results
  • THE EFFECT OF BLOCKING INSULIN-LIKE GROWTH FACTOR-1 (IGF-1)RECEPTOR SYSTEM ON TENDON CELL PROLIFERATION

    The purpose of this study was to find some solutions to the problem of tendon cell proliferation control. Under the condition of in vitro culture, several materials including IGF-1 receptor antibody and mRNA antisense oligonucleotide were added to the culture medium to block the IGF-1-Receptor system. The effect of the material on the tendon cell proliferation was judged by cell count after incubation of 48 hours. The results showed that both IGF-1 Receptor antibody (IGF-1R alpha) and IGF-1 Receptor mRNA antisense oligonucleotide had negative effect on tendon cell proliferation (P lt; 0.01 and P lt; 0.05). These findings lead us to think that the above two materials could be used in the experiment of tendon adhesion preventing and living ready-made tendon producing.

    Release date:2016-09-01 11:07 Export PDF Favorites Scan
  • Research Progress of Relationship Between IGFBP Gene and Pancreatic Cancer

    ObjectiveTo investigate the relationship between insulin-like growth factor binding protein (IGFBP) gene with pancreatic cancer. MethodsThe relevant literatures at home and abroad in recent years were reviewed. From the pancreatic cancer related genes, IGFBP related tumors and the correlation between IGFBP and pancreatic cancer research and other aspects of the previous research results were summaried. ResultsMost of the studies suggested that IGFBP could inhibit the function of tumor cells through the IGF dependent pathway, but the deletion or mutation of IGFBP gene and its regulation mechanism are still unclear. ConclusionIGFBP is closely related to the tumor, but its specific effects and mechanism of pancreatic cancer has not been settled. In order to affect the degree of cell differentiation, regulation of tumor growth and metastasis probability through the change of endogenous IGFBP gene level, the further studie is needed.

    Release date:2016-10-25 06:10 Export PDF Favorites Scan
  • Study of Influence of IGF-1 on Angiogenesis by Using IGF-1 Deficient Mice Breast Cancer Models

    Objective To determine the effect of insulin-like growth factor-1 (IGF-1) on angiogenesis in mouse breast cancer model of lower and normal serum IGF-1 levels after using angiogenesis inhibitor ginsenoside Rg3 (GS Rg3). Methods The breast cancer models were established in control mice and liver specific IGF-1 deficient (LID) mice by feeding DMBA and were treated with GS Rg3. Vascular endothelial growth factor (VEGF) and F8-RAg were detected by immunohistochemical method in breast cancer tissues. IGF-1 gene and angiogenesis relating genes were detected by gene chip in breast cancer and normal breast tissue. Results The incidence rate of breast cancer in LID mice was lower than that in control mice (P<0.05). VEGF expression and microvessel density of LID mice were lower than those in control mice (P<0.05). Compared to the control mice, IGF-1, FGF-1, TGF-β1 and HGF genes were increased, and FGFR-2, PDGF-A and PDGF-B genes were decreased in breast cancer of LID mice. After GS Rg3 treatment, VEGFa, EGF, EGFR, PDGF-A and FGFR-2 genes were increased, IGF-1 and TGF-β1 genes were decreased in breast cancer of LID mice compared with the control mice. Conclusion IGF-1 may be involved in mouse breast cancer progression and associated with the growth of blood vessels. Angiogenesis inhibitor may play an antitumor role by IGF-1 and TGF-β1.

    Release date:2016-09-08 11:07 Export PDF Favorites Scan
  • Retinal neovascularization in neonatal rats induced by methimazole

    Objective To determine the effect of methimazole (MMI) on retinal vascular development in neonatal rats, and to investigate the relationship between the concentration of insulin-like growth factor-I (IGF-I) in serum and the development of normal blood vessels and between the concentration of IGF-I and the formation of abnormal blood vessels. Methods There were 75 neonatal SpragueDawley rats in experimental group whose mothers were raised with water with 0.1% MMI at the first day of parturition. Another 50 neonatal rats were in the control group whose mothers were raised with normal water. The rats in the two groups were sub-divided into 4day and 10day subgroup, respectively. The retinal flatmount of the right eyes were stained with adenosine diphosphatase (ADPase); with the paraffin section of the left eyes, the number of nucleolus breaking through retinal inner limiting membrane was counted and the retinal blood vessels were evaluated. Serum IGF-I levels were detected by radioimmunoassay, and the weight of the neonatal rats in each group were observed and recorded. Results The incidence of retinal neovascularization in 10 day MMI group was 27%, and 0% in 4-day MMI group and control group. The serum IGF-I level in 4-day and 10-day MMI group (73.07 ng/ml, 175.13 ng/ml) was obviously lower than which in the 4-day and 10-day control group (168.73 ng/ml,306.38 ng/ml) (P=0.00). Obvious slow growth of the neonatal rats was found in MMI group compared with which in the control group. Conculsions MMI may inhibit the normal growth of retinal blood vessels and lead neovascularization, which may relate to the initial decrease of the serum IGF-I level.  (Chin J Ocul Fundus Dis, 2007, 23: 198-201)

    Release date:2016-09-02 05:48 Export PDF Favorites Scan
  • Insulin-Like Growth Factor-1 Receptor Overexpression in Pretreatment Biopsies Predicts Response of Rectal Cancer to Preoperative Radiotherapy

    ObjectiveTo evaluate the possible role of the expression of insulin-like growth factor-1 receptor (IGF-1R) in determining rectal cancer radiosensitivity. MethodsThe paired preradiation biopsy specimens and postoperative specimens were obtained from 87 patients with rectal cancer in the department of digestive tumor surgery, Jiangsu Province Hospital of Traditional Chinese Medicine, Affiliated Hospital of Nanjing University of Traditional Chinese Medicine from January 2009 to December 2010. The IGF-1R expression was examined by immunohistochemistry (IHC) and reverse transcription-polymerase chain reaction (RT-PCR). The tumor radiosensitivity was defined according to Rectal Cancer Regression Grade, then the relation between the IGF-1R expression and tumor radiosensitivity was evaluated. ResultsCompared with the preradiation biopsy specimens, IGF-1R expression significantly increased in the paired postoperative specimens of the residual cancer cells (Plt;0.001). The IHC result demonstrated IGF-1R overexpression was significantly associated with a poor response to radiotherapy (rs=0.401, Plt;0.001); RT-PCR detection of IGF-1R expression on preradiation biopsy specimens also showed that IGF-1R mRNA negative patients had a higher radiation sensitivity (rs=0.497, Plt;0.001). ConclusionDetection of IGF-1R expression may predict radiosensitivity of preoperative irradiation for rectal cancer.

    Release date:2016-09-08 10:45 Export PDF Favorites Scan
  • Study of Expression and Significance of IGF-Ⅰin Adipose Tissue of Obese Rats after Roux-en-Y Gastric Bypass Surgery

    ObjectiveTo verify the expression change of insulin-like growth factor-Ⅰ (IGF-Ⅰ) protein and its mRNA before and after Roux-en-Y gastric bypass surgery (RYGB) in obese rats, and to investigate the relationship between the expression of IGF-Ⅰ and proliferation/apoptosis of adipose cells. Methods① Seventy male SD rats were raised at the SPF level circumstance and were randomly divided into control group (NC group, 10 rats) and high fat diet group (60 rats). Rats of high fat diet group were given specific high fat formula diet, rats of NC group were given particular formula diet. After 6 weeks, the body weights of the rats in high fat diet group were measured, and the 20 rats of top weight were selected. The 20 obese rats were randomly divided into 2 groups:gastric bypass (GB) group (n=10) and sham-operation group (SO group, n=10). RYGB were administered to the rats of GB group, and for rats of SO group, sham operations were performed. Rats of NC group did not receive any surgery. Inguinal adipose tissues[represented the subcutaneous adipose tissue (SAT)] and epididymal adipose tissues[on behalf of visceral adipose tissue (VAT)] were taken during operation in rats of GB group and SO group respectively (0.5 g), and 12 weeks after operation in all rats of three groups. The expressions of IGF-Ⅰ protein and its mRNA in adipose tissue were detected by Western blot and real-time fluorescence quantitative PCR. ② Transfection experiment. SAT cells were divided into blank control group (BC group, without transfection), IGF-Ⅰ(+) group (gene overexpression group), IGF-Ⅰ(+) empty vector group, IGF-Ⅰ(-) group (gene silencing group), and IGF-Ⅰ(-) empty vector group. Cells were transfected with corresponding vectors with 3 duplicated holes of each group. Cell viability and apoptosis assays were carried out in 48 hours after transfection. Expressions of protein kinase B (AKT), phosphorylated protein kinase B (p-AKT), phosphoinositide 3-kinase (PI3K), and phosphorylated phosphoinositide 3-kinase (p-PI3K) were detected by Western blot meanwhile. ③ Wortmannin experiment. SAT cells were divided into Wortmannin (+) IGF-Ⅰ(+) group, Wortmannin (+) IGF-Ⅰ(-) group, Wortmannin (-) IGF-Ⅰ(+) group, and Wortmannin (-) IGF-Ⅰ(-) group, which were transfected with corresponding vectors for 24 hours, then adding Wortmannin (0.1 mmol/L). After 24 hours, the expression levels of AKT, p-AKT, p-PI3K, PI3K, and GAPDH were detected by Western blot. Results① PCR results showed that, in SAT, compared with preoperative GB group, the expression levels of IGF-Ⅰ mRNA and its protein in postoperative GB group were both lower (P < 0.01). However, the expression levels of IGF-Ⅰ mRNA and its protein between preoperative SO group and postoperative SO group showed no significant difference (P > 0.05). In VAT, the expression levels of IGF-Ⅰ mRNA and its protein in 5 groups showed no significant difference (P > 0.05). ② The MTT results showed that, IGF-Ⅰ(+) group harbored stronger proliferation abilities compared with its negative control group (P=0.04), whereas IGF-Ⅰ(-) group had lower abilities compared with its negative control group (P=0.04). The results of flow cytometry assay showed that, the apoptosis rate of IGF-Ⅰ(+) group was lower (P=0.04) than that of the corresponding negative control group, and it was higher in IGF-Ⅰ(-) group than that of the corresponding negative control group (P=0.04). ③ Compared with IGF-Ⅰ(+) empty vector group, p-PI3K/PI3K ratio (P=0.03) and p-AKT/AKT (P=0.04) ratio of IGF-Ⅰ(+) group were increased; compared with IGF-Ⅰ(-) empty vector group, p-PI3K/PI3K ratio (P=0.04) and p-AKT/AKT ratio (P=0.04) of IGF-Ⅰ(-) group were decreased. The p-AKT/AKT ratio of Wortmannin (-) IGF-Ⅰ(+) group was higher (P < 0.05) than that of Wortmannin (+) IGF-Ⅰ(+) group; the p-AKT/AKT ratio of Wortmannin (-) IGF-Ⅰ(-) group was lower than that of Wortmannin (-) IGF-Ⅰ(+) group (P < 0.05). ConclusionsIGF-Ⅰ is involved in the accumulation of subcutaneous fat in rats. RYGB can significantly reduce the expression levels of IGF-Ⅰ mRNA and its protein in subcutaneous fat of rats, so as to achieve the effect of weight loss.

    Release date:2016-12-21 03:35 Export PDF Favorites Scan
  • Prognostic Significance of Serum Levels of Vascular Endothelial Growth Factor and Insulin-Like Growth Factor-Ⅰ in Advanced Gastric Cancer Patients Treated with FOLFOX Chemotherapy

    ObjectiveTo evaluate the prognostic significance of serum levels of vascular endothelial growth factor (VEGF) and insulin-like growth factors-Ⅰ (IGF-Ⅰ) in advanced gastric cancer patients who were treated with oxaliplatin/5-fluorouracil (FOLFOX). MethodsNinety-six advanced gastric cancer patients who were treated with FOLFOX in our hospital between March 2007 to August 2010 were enrolled in this study. All of the patients were treated with oxaliplatin (85 mg/m2) as a 2-hour infusion on day 1, and leucovorin (20 mg/m2, about 10 min) on day 1 and day 2, followed by a 5-fluorouracil bolus (400 mg/m2) and 22 hours of continuous infusion of 600 mg/m2. Treatment was repeated in 2-week intervals, and patients received 4 chemotherapy cycle in total. The levels of serum VEGF and IGF-Ⅰ were measured using enzyme-linked immunoassays. The relationship between serum levels of VEGF/IGF-Ⅰ and the clinicopathological characteristics of patients, the relationship between serum levels of VEGF/IGF-Ⅰ and prognosis of patients, were analyzed. ResultsThe serum levels of VEGF and IGF-Ⅰ were (464.4±57.4) pg/mL and (33.5±7.3) ng/mL, respectively. The serum level of VEGF was related with surgical history, Lauren's classification, TNM staging before treatment, and pathological type (P < 0.05), and serum level of IGF-Ⅰ was related with TNM staging before treatment and number of transferred organs (P < 0.05). The serum levels of VEGF and IGF-Ⅰ in stable disease (SD) +progressive disease (PD) patiens were higher than those of complete response (CR) +partial response (PR) patients (P < 0.05). The results of Cox proportional hazard regression model showed that, effect of chemotherapy (HR=1.764, P=0.006), number of transferred organs (HR=1.662, P=0.015), serum level of VEGF (HR=1.834, P=0.012) and IGF-Ⅰ (HR=1.855, P=0.008), were all significantly related with time to progression (TTP); serum level of VEGF (HR=2.205, P=0.002) and IGF-Ⅰ (HR=1.931, P=0.004) were all significantly related with overall survival (OS). ConclusionLevels of serum VEGF and IGF-Ⅰ are independent prognostic factors in patients with advanced gastric cancer who were treated with FOLFOX chemotherapy.

    Release date:2016-12-21 03:35 Export PDF Favorites Scan
  • EFFECTS OF INSULIN-LIKE GROWTH FACTOR 1 ON INHIBITION OF OSTEOBLASTIC PROLIFERATION AND FUNCTION BY ETHANOL

    Objective To investigate the effects of insulin-like growth factor 1(IGF-1) and ethanol (EtOH) on the changes in the osteoblast proliferation and the osteoblast function under the normal serum concentration and serum starvationMethodsThe osteoblasts harvested from the SD rat calvaria were incubated in the following six conditions according to the supplements in DMEM: the F15group:15% newborn calf serum (NCS); the F15/EtOH group:100 mmol/L of EtOH added to 15% NCS; the F2 group:2% NCS; the F2/EtOH group:100 mmol/L of EtOH added to 2% NCS;the F2/IGF-1 group:25ng/ml of IGF-1 added to 2% NCS;the F2/IGF-1/EtOH group:100 mmol/L EtOH added to 25 ng/ml IGF-1 and 2% NCS. The osteoblasts were analyzed by the MTTassay, alkaline phosphatase(ALP) activity, and RTPCR at 24, 48, 72 and 96h ours after the culture. Results The absorbance (A), the ALP activity, and the expression of BGP mRNA (the proliferation and function indicators of the osteoblasts) were significantly decreased in the F15/EtOH group at all the time points when compared with those in the F15the group (P< 0.05); the above 3 indicators were significantly decreased in the F2 groupwhen compared with those in the F15 group (P<0.05); they were significantly decreased in the F2/EtOH group when compared with those in the F2 group (P<0.05); however, the indicators in the F2/IGF-1 group were significantly increased when compared with those in the F2 group (P<0.05); the A value in the F2/IGF-1/EtOH group was not significantly decreased when compared with that in the F2/IGF-1 group, with an exception of the A value at 24 hours (P>0.05); however, ALP and BGP mRNA were significantly decreased (P<0.05). All the indicators were significantly increased when compared with those in the F2/EtOH group (P<0.05) Conclusion Ethanol can inhibit the osteoblast proliferation and the osteoblast function, and can increase the inhibition when the osteoblasts were cultured under the serum starvation. This may be one of the mechanisms for alcoholic bone disease. IGF-1 can prevent the inhibition of the osteoblasts under the serum starvation and counteract the ethanolinduced proliferation inhibition; therefore, IGF-1 is an alternaive therapeutic intervention for alcoholic bone disease.

    Release date:2016-09-01 09:22 Export PDF Favorites Scan
  • The Effects and Related Mechanism of IGF-1-Treated Mesenchymal Stem Cells in Pulmonary Fibrosis in Rats

    【Abstract】 Objective To explore the new therapy for pulmonary fibrosis by observing the effects of insulin-like growth factor 1 ( IGF-1) treated mesenchymal stemcells ( MSCs) in rats with bleomycin-induced pulmonary fibrosis. Methods Bone marrowmesenchymal stemcells ( BMSCs) were harvested from6-week old male SD rats and cultured in vitro for the experiment. 48 SD rats were randomly divided into 4 groups, ie.a negative control group ( N) , a positive control group/bleomycin group ( B) , a MSCs grafting group ( M) ,and an IGF-1 treated MSCs grafting group ( I) . The rats in group B, M and I were intratracheally injected with bleomycin ( 1 mL,5 mg/kg) to induce pulmonary fibrosis. Group N were given saline as control. Group M/ I were injected the suspension of the CM-Dil labled-MSCs ( with no treatment/pre-incubated with IGF-1 for 48 hours) ( 0. 5mL,2 ×106 ) via the tail vein 2 days after injected bleomycin, and group B were injected with saline ( 0. 5 mL) simultaneously. The rats were sacrificed at 7,14,28 days after modeling. The histological changes of lung tissue were studied by HE and Masson’s trichrome staining. Hydroxyproline level in lung tissue was measured by digestion method. Frozen sections were made to observe the distribution of BMSCs in lung tissue, and the mRNA expression of hepatocyte growth factor ( HGF) was assayed by RTPCR.Results It was found that the red fluorescence of BMSCs existed in group M and I under the microscope and the integrated of optical density ( IOD) of group I was higher than that of group M at any time point. But the fluorescence was attenuated both in group M and group I until day 28. In the earlier period, the alveolitis in group B was more severe than that in the two cells-grafting groups in which group I was obviously milder. But there was no significant difference among group I, M and group N on day 28.Pulmonary fibrosis in group B, Mand I was significantly more severe than that in group N on day 14, but itwas milder in group M and I than that in group B on day 28. Otherwise, no difference existed between the two cells-grafting groups all the time. The content of hydroxyproline in group B was significantly higher than that in the other three groups all through the experiment, while there was on significant difference betweengroup I and group N fromthe beginning to the end. The value of group M was higher than those of group I and group N in the earlier period but decreased to the level of negative control group on day 28. Content of HGF mRNA in group Nand group I was maintained at a low level during the whole experiment process. The expression of HGF mRNA in group I was comparable to group M on day 7 and exceeded on day 14, the difference of which was more remarkable on day 28. Conclusions IGF-1 can enhance the migratory capacity of MSCs which may be a more effective treatment of lung disease. The mechanismmight be relatedto the increasing expression of HGF in MSCs.

    Release date:2016-08-30 11:55 Export PDF Favorites Scan
  • EXPERIMENTAL RESEARCH OF ARTICULAR CARTILAGE DEFECT REPAIR USING MICRO-FRACTURE AND INSULIN-LIKE GROWTH FACTOR 1 IN RABBITS

    ObjectiveTo investigate the effects of micro-fracture and insul in-l ike growth factor 1 (IGF-1) in treatment of articular cartilage defect in rabbits. MethodsTwenty-four New Zealand white rabbits (aged, 4-6 months; weighing, 2.5-3.5 kg) were randomly divided into 4 groups (n=6):micro-fractures and recombinant human IGF-1 (rhIGF-1) treatment group (group A), micro-fracture control group (group B), rhIGF-1 treatment control group (group C), and blank control group (group D). Full thickness articular cartilage defects of 8 mm×6 mm in size were created in the bilateral femoral condyles of all rabbits. The micro-fracture surgery was performed in groups A and B. The 0.1 mL rhIGF-1 (0.01 μg/μL) was injected into the knee cavity in groups A and C at 3 times a week for 4 weeks after operation, while 0.1 mL sal ine was injected in groups B and D at the same time points. At 4, 12, and 24 weeks, the gross, histological, and immunohistochemical observations were performed, and histological score also was processed according to Wakitani's score criteria. The collagen contents in the repair tissues and normal patellofemoral cartilage were detected by the improved hydroxyproline (HPR) method at 24 weeks. Electron microscope was used to observe repair tissues of groups A and B at 24 weeks. Results All animals were survival at the end of experiment. At 24 weeks after operation, defect was repaired with time, and the repair tissue was similar to normal cartilage in group A; the repair tissue was even without boundary with normal cartilage in group B; and the repair tissue was uneven with clear boundary with normal cartilage in groups C and D. Histological staining showed that the repair tissues had no difference with normal cartilage in group A; many oval chondrocytes-l ike cells and l ight-colored matrix were seen in the repair tissues of group B; only a few small spindle-shaped fibroblasts were seen in groups C and D. Moreover, histological scores of group A were significantly better than those of groups B, C, and D (P<0.05) at 4, 12, and 24 weeks. Electron microscope observation showed that a large number of lacuna were seen on the surface of repair tissue in group A, and chondrocytes contained glycogen granules were located in lacunae, and were surrounded with the collagen fibers, which was better than that in group B. Collagen content of the repair tissue in group A was significantly higher than that in groups B, C, and D (P<0.05), but it was significantly lower than that of normal cartilage (P<0.05). Conclusion Combination of micro-fracture and rhIGF-1 for the treatment of full thickness articular cartilage defects could promote the repair of defects by hyaline cartilage.

    Release date: Export PDF Favorites Scan
4 pages Previous 1 2 3 4 Next

Format

Content