OBJECTIVE: To investigate the effect of electroacupuncture on mRNA expression of NGF and IGF-1 in injured nerve. METHODS: Sciatic nerve injury model was established by transection of right side sciatic nerve in 90 male SD rats, which were randomly divided into two groups. The experimental group was treated with electroacupuncture, no treatment in the control group. The distal part of the injured nerve was harvested after 1, 2, 4, 6 and 10 weeks of operation and stored in the liquid nitrogen. The total RNA was extracted by the TRIzol reagent. Reverse transcriptase-polymerase chain reaction(RT-PCR) was used to detected the mRNA expression of NGF and IGF-1. RESULTS: The mRNA expression of NGF in the experimental group was increased quickly from the second week, and reached to highest level in the fourth week. It was much higher than that of the control group (P lt; 0.05). Then it began to decline in following time and approximately reached to the level of the first week after 10 weeks of operation. The mRNA expression of IGF-1 in the experimental group was remarkably increased in the second and fourth week, and which was much higher than that of the control group respectively(P lt; 0.05). Although the mRNA expression of IGF-1 after 10 weeks of operation in the experimental group was higher than that of the control group, but there was no significant difference between the two groups(P gt; 0.05). There was linear correlation in the fourth week between mRNA expression of NGF and IGF-1 in the experimental group. CONCLUSION: The mRNA expression of NGF and IGF-1 can be elevated in injured nerve at early stage interfered with electroacupuncture.
Objective To investigate the effects of the insulin-like growth factor 1 (IGF-1), the transforming growth factor β1(TGFβ1), and the basic fibroblast growth factor (bFGF) on proliferation and cell phenotype of the human fetal meniscal cells, and to find out the best combination and concentration of the growth factors for the meniscus tissue engineering. Methods The fetus came from the healthy woman accidental abortion and the procedure had got her approval.The human fetal meniscal fibrochondrocytes were cultured in vitro. The cell phenotype was identifiedby the collagen type Ⅱ immunohistochemistry and Aggrecan immunofluorescence. Inthe growth factor groups, the 3rd passage meniscal cells synchronized by the serum starvation method and were mixed with IGF-1 (1, 10, 50, 100 μg/L), TGF-β1 (0.1, 1.0, 5.0, 10.0, 50.0 μg/L), and bFGF (5, 10, 50, 100, 200 μg/L), respectively, and in the combination groups, the combinations of bFGF and TGF-β1, bFGF and IGF-1, TGF-β1 and IGF-1 were established at their optimal effect concentrations. The control group was also established for comparison. The dose-response relationship was studied at 48 h and 72 h bythe MTT colorimetric method. Results The 3rd passage meniscalcells could express collagen type Ⅱ and Aggrecan before and after the addition of the three growth factors. The proliferating effects of the growth factors (IGF-1 50 μg/L,TGF-β1 5 μg/L,bFGF 50 μg/L) on the 3rd passage cells at 48 h and 72 h were significantly better in the growth factor groups than in the control group (Plt;0.05),and the combination groups of bFGF 50 μg/L and IGF-1 50 μg/L, IGF-1 50 μg/L and TGF-β1 5 μg/L showed a significantly higher proliferatingeffect than that in the single growth factor group (Plt;0.05). bFGF 50 μg/L and TGF-β1 5 μg/L had no synergetic effect (Pgt;0.05). Conclusion IGF-1, TGF-β1 and bFGF can promote the proliferation of the human fetal meniscal cells, respectively, and the combinations of bFGF and IGF-1, IGF-1 and TGF-β1 at their optimal concentrations can have better proliferating effects than the single growth factor. They can be used for the in vitro amplification of the meniscal seed cells.
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.
For the purpose of understanding the distribution of insulin-like growth factor-1 (IGF-1) receptor on the tendon cell, the continuous cultured tendon cell line was studied by following experiments. With the methods of immunohistochemical study and flow cytometric study, the density of IGF-1 receptor of the primary, 6th and 13th generation of tendon cell was analyzed. The results showed that there was no difference of the receptor density among those generations. However, in the cell cycle, the numbers of IGF-1 receptor in G2M phase tendon cells were more than that in G1 phase cells (P lt; 0.01). These works provided sufficient evident which suggested there were stable density of IGF-1 receptor on the tendon cell though out the life span of tendon cell. This may build some foundation in growth control of tendon cell by growth factor in the research of tendon tissue engineering.
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.
Objective
To probe the relationship between the levels of two hormone,growth hormone (GH) and insulin-I like growth factor-I(IGF-I),and diabetic retinopathy (DR) in the patients with noninsulindependent diabetic mellitus (NIDDM). Methods
The direct radioimmunoassay was used to determine GH and IGF-I in the serum of 38 normal cotrols,61 NIDDM patients without DR,77 patients with the simple DR and 48 patients with the proliferative DR.Difference among these groups were analysed and compared by the methods of t test,F test and correlation analysis. Results
The results showed that the levels of GH and IGF-I in the patients with diabetes [GH(1.659plusmn;1.509)ng/ml,IGF-I(118.7plusmn;52.0) ng/ml] were significantly higher than those in the normal controls [GH(0.619plusmn;0.351)ng/ml,IGF-I (63.6plusmn;30.6) ng/ml)] (P<0.01),and those in the DR group were higher than those in the NIDDM without retinopathy group (P<0.01),and levels of GH and IGF-I in the proliferative DR group [GH(2.953plusmn;1.648) ng/ml,IGF-I (159.2plusmn;47.5) ng/ml] ) were significantly higher than those in the simple DR group [GH(1.742plusmn;1.523) ng/ml,IGF-I (123.6plusmn;40.6) ng/ml] (P<0.01).SeveritY of DR was positively correlated with the levels of GH and IGF-I(P<0.01). Conclusion
The results indicate that GH and IGF-I levels in the serum of patients with diabetes might be correlated with mechanisms and development of DR. (Chin J Ocul Fundus Dis,2000,16:30-31)
Objective To investigate the expressions of CD90, IGF1R, and hTERT protein in hepatocellular carcinoma, and the correlations of each other in the development of carcinoma. Methods The expressions of CD90, IGF1R, and hTERT protein in hepatocellular carcinoma were detected by S-P immunohistochemical staining, 20 cases of normal liver tissues were collected as contrast, and to compare the relations between expression and prognosis or survival rate. Results The positive rate of CD90, IGF1R, and hTERT protein in hepatocellular carcinoma group were obviously higher than that in contrast group(P<0.05), which was 63.9% vs. 0, 52.8% vs.5.0%, and 47.2% vs.0, respectively. The positive rate of CD90, IGF1R, and hTERT protein were higher in UICC Ⅲ-Ⅳ stage group than that in UICC stage Ⅰ-Ⅱ group(P<0.05), which was 79.2% vs.33.3%, 70.8% vs.16.7%, and 62.5% vs.16.7%, respectively. There was a statistically significant positive correlation observed between the expressions of CD90 and IGF1R protein (Kendall’s tau-b=0.563 1, P<0.05), so it was with CD90 and hTERT protein (Kendall’s tau-b=0.363 6, P<0.05). The survival rates of positive expressions of CD90, IGF1R, and hTERT protein were lower than negative expressions of CD90, IGF1R, and hTERT(P<0.05), which was 21.7% vs.50.0%, 17.6% vs.43.8%, and 20.0% vs.38.9%, respectively. Conclusions The expressions of CD90, IGF1R, and hTERT may have correlations with the progress of HCC, and may serve as a marker for HCC prognosis potentially.
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.
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.
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.