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 ethanolinduced proliferation inhibition; therefore, IGF-1 is an alternaive therapeutic intervention for alcoholic bone disease.
OBJECTIVE: To investigate the effect of combined treatment of recombinant human growth hormone (rhGH) and insulin-like growth factor-1 (IGF-1) on wound healing and protein catabolism in burned rats. METHODS: Forty Wistar rats with deep II degree scald injury were divided randomly into four groups and received rhGH (0.1 U/kg.d), rhGH (0.1 U/kg.d) plus IGF-1 (2.0 mg/kg.d), IGF-1 (2.0 mg/kg.d) and Ringer’s solution (2 ml/kg.d, as control group) respectively. The wound healing time and protein catabolism levels of every groups were compared after 2 weeks. RESULTS: Total body weight began to increase after 2 weeks in rhGH group and rhGH plus IGF-1 group, but in control group, it was occurred after 4-5 weeks. The body weight of rhGH plus IGF-1 group was 1.65 times than that of rhGH group. The wound healing time in rhGH plus IGF-1 group (17.1 +/- 4.4) days was significantly lower than that of rhGH (20.5 +/- 4.8) days and control group (29.7 +/- 6.3) days. The protein level of rhGH plus IGF-1 group was significantly higher than that of control group and rhGH group. CONCLUSION: It suggests that rhGH plus IGF-1 with synergism is more effective in promoting wound healing and increasing the protein catabolism.
【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.
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.
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.
Objective To investigate the effect of combined delivery of hepatocyte growth factor (HGF) and insulinlike growth factor-1 (IGF-1) on the development of bone mesenchymal stem cells (BMSCs) differentiation by expression of GATA-4,and to supply some evidence for clinical BMSCs transplantation therapy. Methods BMSCs were isolated from the femurs and tibias of the randomly assigned rabbits and cocultured with myocytes in a ratio of 1∶1. Myocytes were obtained from neonatal rabbits ventricles. 150 ng/ml HGF and 200 ng/ml IGF-1 were added into 4 culture bottles of 8 bottles and the other 4 bottles were not. After BMSCs were cocultured with myocytes for 1 day, 3 days, 1 week, and till 6 weeks, differentiated BMSCs were targeted and microdissected with a laser capture microdissection system, and then ribonucleic acid (RNA) was extracted and isolated. The differentiation of BMSCs in coculture was confirmed by immunohistochemistry, electron microscopy, and reverse transcriptionpolymerase chain reaction (RT-PCR). And expression of GATA-4 in BMSCs was detected by semiquantitative RT-PCR. Results Before coculturing, the BMSCs were negative for α-actinin and exhibited a nucleus with many nucleoli. After coculture with myocytes, some BMSCs became αactininpositive and showed a cardiomyocytelike ultrastructure, including sarcomeres, endoplasmic reticulum, and mitochondria. BMSCs cocultured with myocytes expressed cardiac transcription factor GATA-4. IGF-1 and HGF delivery can significantly increased expression of GATA-4 for the differentiated BMSCs as compared with cells of no delivery of HGF and IGF-1. The expression level of GATA-4 in captured BMSCs began to increase at the 1st day, reach the peak at the 2nd week and kept high expression level after the 2nd week. Conclusion BMSCs can transdifferentiate into cells with a cardiac phenotype when cocultured with myocytes. Differentiated myocytes express cardiac transcription factors GATA-4. Administration of HGF and IGF-1 promoted the development of BMSCs transdifferentiate into cardiac phenotype, which is associated with the increase in expression level of GATA-4.
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.