Objective To explore the ability of insulin-like growth factor-Ⅰ (IGF-Ⅰ) and hyaluracan acid in prompting chondrogenesis of engineering cartilage tissue.Methods Human articular chondrocytes were isolatedand cultured in DMEM plus 10% fetal bovine serum. They were divided into three groups：hyaluracan acid+chondrocytes + IGF-Ⅰ group(IGF-Ⅰ group), hyaluracan acid+chondrocytes group(cell group), hyaluracan acid group(control group). The ability of chondrogenesis was investigated by HE and toluidine blue staining, human collagen Ⅱ immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR).Results Both cell group and IGF-Ⅰ group could develop into cartilage tissue in the sixth week while control group could not. The number of cartilage lacuna in IGF-Ⅰ group were more than that in cell group. Human collagen Ⅱ immunohistochemistry showed that there were ber positive cell in IGF-Ⅰ group than in cell group, collagen Ⅱ mRNA expression was more higher and collagen Ⅰ mRNA expression was lower in IGF-Ⅰ group than in cell group. Conclusion Insulin growth factorⅠ can prompt chondrogenesis of engineering cartilage tissue and ameliorate the quality of engineering cartilage tissue in vitro.
Objective To investigate the influenceof insulin-like growth factor-I (IGF-I) on biological characteristics of articular chondrocytes cultured in vitro of rabbits. Methods Monolayer articular chondrocytes of 4week old rabbits were cultured in medium with IGF-I, at the concentrations of 3, 10, 30, 100, and300ng/ml. The DNA content in cells and glucuronic acid content in matrix were detected on the 2nd, 4th, 6th days after culture. Results The DNA content in cells and the glucuronic acid content in matrix in articular chondrocytes cultured in medium with IGF-I at concentrations of 3-300ng/ml were all significantly higher than those in control group (P＜0.01), which reached the peak at the concentrations of 30-100mg/ml on the 4th day. Conclusion IGF-I could obviously promote theproliferation of articular chondrocytes in vitro, and there exist time-dependent and dose-dependent effect.
Objective To study the effect of two cytokines, basic fibroblast growth factor(bFGF) and insulin-like growth factor-I(IGF-I), on cell proliferation in chondrocytes of adult rabbits. Methods The primary chondrocytes of adult rabbits were harvested and cultured with bFGF and IGF-I at different concentrations,respectively, as well as with the mixture of the two cytokines; the quantity of cultured chondrocytes was detected by MTT assay at the 24th, 48th and 72th hours; and the final fold increase of different groups was measured by cell count for the 3rd passage; and the proliferation index of the groups was recorded by flowing cytometer on the 14th day. Results ① The cultured chondrocytes with either bFGF, IGF-I or their mixture were significantly more than that of control group at the 24th, 48th and 72th hours (P＜0.01). ② After the 3rd passage, the final folds of proliferation were significantly higher in the groups with cytokinesthan in the control group (P＜0.01); and the final fold with the mixture ofcytokines was significantly higher than that of both IGF-I and bFGF (P＜0.01). ③ Theproliferation index was significantly higher in the groups with cytokines than in the control group (P＜0.01); the proliferation index with the mixture of cytokines was significantly higher than that of both IGF-I and bFGF (P＜0.05); besides, proliferation index was higher when cytokine was applied twice than once (P＜0.05). Conclusion bFGF and IGF-I could promote chondrocytes proliferation of adult rabbits obviously and they are synergistic in cell proliferation.
ObjectiveTo review the research progress of the relationship between the insulin resistance, insulin-like growth factor-Ⅰ(IGF-Ⅰ), insulin-like growth factor-Ⅱ(IGF-Ⅱ), and colorectal cancer, and to explore the future research trends. MethodsThe related literatures in recent 5 years from abroad databases (PubMed, Web of Science, and EMBASE)and domestic databases (CNKI, WANFANG, and WEIPU)were collected and reviewed. ResultsThe research on the correlation between the changes and colorectal cancer with insulin resistance and IGF-Ⅰand IGF-Ⅱlevels, epidemiological studies and the mechanism research, indicates that there are complex and close relationship between them. ConclusionsThe research about the relationship between the insulin resistance, IGF-Ⅰ, IGF-Ⅱ, and colorectal cancer is promising.However, many issues need to be further investigated.
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.
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.