Objective To investigate the effect of imatinib mesylate on radiation-induced lung injury mice and its influence on the oxidative stress and transforming growth factor-β1 (TGF-β1) expression in mice. Methods Forty-five C57BL/6 mice were divided into a treatment group, a control group and a model group. The treatment group and model group were given radiation of 18 Gy delivered in the thorax. After 4 h daily of the radiation, the treatment group received imatinib mesylate of 0.081 g/kg, while the other groups were given normal saline solution. The experiments were continued for 30 days. After the experiments, the lungs of mice were divided into 4 parts. The haematoxylin and eosin and immunohistochemical stain were prepared to observe the situation of pathology and TGF-β1. The lung homogenate was prepared and the levels of superoxide dismutase (SOD), malondialdehyde (MDA), total antioxidant capacity (T-Aoc) and glutathione peroxidase (GSH-PX) were detected. Results The levels of GSH-PX, T-Aoc and SOD were (173.15±12.21) U, (119.33±11.06) U/mgprot and (1.73±0.33) nmol/mgprot in the treatment group, significantly higher than the control group, while the levels of MDA was (0.68±0.08) nmol/mgprot, significantly lower than the control group (P<0.05). The HE and immunohistochemical stain showed that there were mild alveolar inflammatory changes in the treatment group while such changes were serious in the model group. The scores of HE and immunohistochemical were 1.26±0.12 and 0.31±0.12 in the treatment group, significantly lower than those in the control group (P<0.05). Conclusion The imatinib mesylate can effectively ameliorate the oxidative stress and inhibite TGF-β1 expression in radiation-induced lung injury mice.
Objective To observe the expression and distribution of transforming growth factor-β1 (TGF-β1) in the healing process of bile duct and discuss its function and significance in the process of benign biliary stricture formation. Methods An injury to bile duct of dog was made and then repaired. The expression and distribution of TGF-β1 in the tissue at different time of the healing process were studied after operation with immunohistochemical SP staining. Results TGF-β1 staining was observed in the granulation tissue, fibroblasts and endothelial cells of blood vessels. High expression of TGF-β1 was observed in the healing process lasting for a long time. Conclusion The high expression of TGF-β1 is related closely with the fibroblast proliferating activity, extracellular matrix overdeposition and scar proliferation in the healing process of bile duct.
Objective To investigate the effects of exogenous bone morphogenetic protein(BMP) and transforming growth factor-β(TGF-β) on biomechanical property for ulna of fracture healing.Methods Thirty-six adult rabbits were made the model of right ulnar fracture and treated locally with TGF-β/PLA, BMP/PLA，TGF-β+BMP/PLA or PLA(as control group). Fracture healing was evaluated by measurement of the mechanical parameters and geometric parameters.Results As compared with control group, the geometric parameters, the bending broken load, the ultimatebending strength, the bending elastic modulus, the ultimate flexural strength, the flexural elastic modulus, the ultimate compressing strength, the compressingelastic modulus, and the ultimate tensile strength for ulna of fracture healingincreased significantly in the treatment groups(P＜0.01). These parameters were higher in TGF-β+BMP/PLA group than in TGF-β/PLA group or in BMP/PLA group andin TGF-β/PLA group than in BMP/PLA group(P＜0.05). There was no significant difference in bone density between the treatment groups and control group. Conclusion Local application of exogenous TGF-β and BMP canincrease the callus formation and enhance biomechanical strength of bone after fracture healing. A combination of TGF-β and BMP has synergetic effect in enhancing fracture healing.
ObjectiveTo investigate the effect of peroxisome proliferator-activated receptorγ(PPARγ) agonist on bile duct fibrosis induced by transforming growth factor-β1 (TGF-β1). MethodsPrimary cultures of bile duct fibroblast were treated with different concentrations of pioglitazone (PGZ) or 15-deoxy-Δ12, 14-prostaglandin J2 (15d-PGJ2) and then treated with TGF-β1. The mRNA levels of collagenⅠ(COLⅠ)、fibronectin (FN)、α-smooth muscle actin (α-SMA) and connective tissue growth factor (CTGF) were determined by RT-PCR. ResultsPGZ and 15-d-PGJ2 could down regulated the mRNA levels of COLⅠ, FN, α-SMA and CTGF induced by TGF-β1 (3 ng/mL). The same concentration of 15d-PGJ2 was a more potent inhibitor ofα-SMA and less potent inhibitor of COLⅠthan PGZ. But PGZ had the same effect as 15d-PGJ2 on CTGF. ConclusionPPARγagonist can prevent fibrosis induced by TGF-β1.
【Abstract】Objective To investigate the apoptosis induced by TGF-β1 in human hepatic carcinoma cell lines and its relationship with p53 gene and Smad. Methods Three human hepatic carcinoma cell lines which involving in various status of the p53 gene were used in this study. TGF-β1-induced apoptosis in hepatic carcinoma cell lines was measured by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. To study the mechanism of TGF-β1-induced apoptosis, these cell lines were transfected with a TGF-β1-inducible luciferase reporter plasmid containing Smad 4 binding elements (SBE) and luciferase gene using Lipofectamine 2000, then treated with TGF-β1, relative luciferase activity was assayed. Results Of three cell lines studied with TUNEL assay, TGF-β1 induced apoptosis was observed in HepG2 cells (wild type p53). Huh-7 (mutant p53) and Hep3B (deleted p53) cell lines showed less apoptosis. Luciferase activity assay indicated that the response to TGF-β1 induction in HepG2 cells was increased dramatically but was not significant in Huh-7 and Hep3B cell lines. Conclusion HepG2 cells seem to be highly susceptible to TGF-β1-induced apoptosis compared with Hep3B and Huh7 cell lines. Smad 4 is a central mediator of the TGF-β1 signal transduction pathway.
Objective To investigate the effect of transforming growth factor-β1 (TGF-β1) gene transfer on the biological characteristics of osteoblasts. Methods The expression of TGF-β1 in the transfected osteoblasts was detected by in situ hybridization and assay of TGF-β1 activity in the supernatant (minklung epithelium cell growth -inhibition test). The effects of gene transfer andsupernatant of the transfected osteoblasts on the proliferation and alkaline phosphatase(ALP) activity of osteoblasts were detected by 3 H-TdR and MTT. Results The results of in situ hybridization analysis suggested that the osteoblasts transfected by TGF-β1 gene could express TGF-β1 obviously. The complex medium, which was the mixture of serum-free DMEM and the activated supernatant according to 1∶1, 1∶2, 1∶4, could inhibit growth of Mv-1-Lu evidently and the ratios ofinhibition were 16.3%, 22.7%, 28.2% respectively. TGF-β1 gene transfer hadno effect on the biological characteristics of osteoblasts, but the activated supernatant of transfected osteoblasts stimulated proliferation and inhibited ALPactivity of osteoblasts. Conclusion TGF-β1 gene transfer promotes the expression of TGF-β1 and the biological characteristics of trasfected osteoblasts are stable, which is helpful for gene therapy of bone defects in vivo.
Objective To study the influence of transforming growth factor-β1(TGF-β1), dentin non-collagen proteins(dNCPs) and their complexon tissue engineering pulp system. Methods Collagen I and dentin powder were used to construct the system of pulp cells in 3dimensional culture, dentin powder was added in the gel. The tissue engineering pulp were divided TGF-β1 group, dNCPs group, TGF-β1/dNCPsgroup and control group.After3, 6 and 14 days, the appearance and the differentiation of pulp cells were observed by HE staining and immunohistochemical staining -respectively. Results Collagen I could form netted collagen gel construction. Growing condition of pulp cells in gel was similar to that of pulp cells in vivo. After the TGF-β1 and dNCPswere added, the pulp cells had some characteristics of odontoblasts and had unilateral cell process after culture 6 days. Pulp cells arranged with parallel columnar and form dentin-pulp-like complex after 14 days. Immunohistochemical staining showed dentin salivary protein(DSP) began to express in some cells.The number of positive cell was most in the TGF-β1 group. No positive cells were detected in the control group. Conclusion The transforming growth factor-β1 and noncollagen proteins can stimulate the pulp cells to transform into odontoblasts to some extent, which promote the formation of tissue engineering pulp.
Objective To review the recent advances in transforming growth factor-β(TGF-β) super family study and its role in new bone formation. Methods The latest original articles related to this subject were retrieved extensively,especially the effect of TGF-β, bone morphogenetic proteins(BMPs) and activin(ACT) on distractionosteogenesis. Results TGF-β, BMPs and ACT play important roles in prompting new bone formation and each of them has different effects. Among them, TGF-β can stimulate the proliferation of osteoblast and synthesis ofextra cellular medium; BMPs can initiate the differentiation of interstitial cell toosteocyte; then ACT displays the combine effect of above two factors. Conclusion TGF-β superfamily can regulate new bone formation and thus shorten the course of mandibular distraction osteogenesis.
Objective To investigate the effects of adenovirus-mediated melanoma differentiation-associated gene-7 (mda-7)/IL-24 and/or adriamycin (ADM) on transplanted human hepatoma in nude mice and to explore a new way for hepatoma gene therapy combined with chemotherapy. Methods The recombinant adenovirus vector carrying Ad.mda-7 was constructed; Ad.mda-7 and/or ADM were injected into the tumor-bearing mice. Their effects on the growth of the tumor and the survival time of the mice were observed. The expressions of VEGF and TGF-β1 were detected by an immunohistochemistry method. Results Ad.mda-7 was constructed and expressed in vivo successfully. Compared with other three groups 〔control group (43.4±1.67) d, ADM group (64.2±4.14) d, Ad.mda-7 group (61.4±1.67) d〕, the mice treated with Ad.mda-7 combined with ADM had longer average survival time 〔(83.8±4.82) d, P＜0.01〕; the average size of tumor treated with Ad.mda-7 combined with ADM diminished significantly compared with that treated with ADM or Ad.mda-7 separately (P＜0.01). VEGF and TGF-β1 expressions of Ad.mda-7 group were (56.2±7.7)%, (35.2±4.5)%, respectively, and were lower than those in ADM group (VEGF: P＜0.05; TGF-β1: P＜0.01). VEGF expression of Ad.mda-7+ADM group was (37.3±5.0)%, and was significantly lower than that in other three groups (P＜0.01). TGF-β1 expression of Ad.mda-7+ADM group was (31.2±3.1)% and significantly lower than that in control group and ADM group (P＜0.01), however, there was no significant difference compared with Ad.mda-7 group (Pgt;0.05). Conclusion Ad.mda-7 combined with ADM has b antitumor potency and synergistic effects and suppresses the growth of human HCC xenograft in nude mice, possibly by inducing the apoptosis of hepatoma cell lines and suppressing tumor angiogenesis.
ObjectiveTo investigate the early diagnostic value of transforming growth factor-β1(TGF-β1) on acute rejection after liver transplantation in rhesus by detecting the expression of TGF-β1 in the liver tissue. MethodsLiver transplantation models in rhesus were constructed by the improved vascular dual cuff, supporting tube of biliary tract, and artery anastomosis method.The successful models were randomly divided into experimental group (no immunosuppressant treatment in perioperative period) and control group (treated by immunosuppressant in perioperative period).Then the blood samples and liver tissues were collected at 6, 12, 24, and 72 hours after surgery.Allograft rejections of liver tissue after liver transplantation were monitored by liver function test, hematoxylin-eosin staining and Banff score.Finally, the expression level of TGF-β1 was detected by Western blot analysis or immunohistochemistry technique. Results①The acute rejection happened in all the rhesus at 12 h, 24 h and 72 h after liver transplantation, especially at 72 h after liver transplantation in the experimental group, the Banff grade levels of acute rejection in the liver tissue was more severe than that in the control group (P < 0.05).②The levels of ALT, AST, and TBIL after liver transplantation was gradually increased, which were similar at 6 h and 12 h after transplantation between the two groups, but which at 24 h and 72 h after transplantation in the experimental group were significantly higher than those in the control group (P < 0.05).③The results of TGF-β1 protein expression using immunohistochemical detection:The percentage of positive area of TGF-β1 of liver tissue at 12 h in the experimental group was significantly higher than that in the control group (P < 0.05).With the extension of time, it was gradually increased and significantly higher than that in the control group at 24 h or 72 h (P < 0.05).④The semi-quantitative results of TGF-β1 protein expression using Western blot detection:The TGF-β1 protein expressions began to increase at 6 h after liver transplantation in the experimental group and the control group, and the magnitude of increase was more obvious in the experimental group.The TGF-β1 protein expressions at different time (6 h, 12 h, 24 h, and 72 h) in the experimental group were significantly higher than those in the control group (P value was 0.003, 0.001, 0.001, and 0.001, respectively). ConclusionsThe elevated level of TGF-β1 of liver tissue after liver transplantation might suggest the enhanced cellular immune function, it might have certain significance for early diagnosis of acute rejection after liver transplantation.