Expression of Transforming Growth Factor β_(1) in Mesenchymal Stem Cells: Potential Utility in Molecular Tissue Engineering for Osteochondral Repair

The feasibility of using gene therapy to treat full-thickness articular cartilage defects was investigated with respect to the transfection and expression of exogenous transforming growth factor(TGF)-β_(1)genes in bone marrow-derived mesenchymal stem cells(MSCs)in vitro.The full-length rat TGF-β_(1)cDNA was transfected to MSCs mediated by lipofectamine and then selected with G418,a synthetic neomycin analog.The transient and stable expression of TGF-β_(1)by MSCs was detected by using immunohistochemical staining.The lipofectamine-mediated gene therapy efficiently transfected MSCs in vitro with the TGF-β_(1)gene causing a marked up-regulation in TGF-β_(1)expression as compared with the vector-transfected control groups,and the increased expression persisted for at least 4 weeks after selected with G418.It was suggested that bone marrow-derived MSCs were susceptible to in vitro lipofectamine mediated TGF-β_(1)gene transfer and that transgene expression persisted for at least 4 weeks.Having successfully combined the existing techniques of tissue engineering with the novel possibilities offered by modern gene transfer technology,an innovative concept,i.e.molecular tissue engineering,are put forward for the first time.As a new branch of tissue engineering,it represents both a new area and an important trend in research.Using this technique,we have a new powerful tool with which:(1)to modify the functional biology of articular tissue repair along defined pathways of growth and differentiation and(2)to affect a better repair of full-thickness articular cartilage defects that occur as a result of injury and osteoarthritis.

Study of Rat Osteoblasts Transfected by Transforming Growth Factorβ_(1)Gene

Summary:In order to investigate the effect of TGFβ_(1) gene transfer on the biological characteristics,the effects of gene transfer and supernatant of transfected osteoblasts on the proliferation and ALP activity of osteoblasts were detected by ^(3)H-TdR and MTT.Our results showed that TGFβ_(1) gene transfer had no effect on the biological characteristics and the activated supernatant of transfected osteoblasts stimulated proliferation and inhibited ALP activity of osteoblasts.TGFβ_(1) gene transfer could promote the expression of TGFβ_(1) and the biological characteristics of transfected osteoblasts were stable,which might be helpful for gene therapy of bone defects in vivo.

Effects of Lingguizhugan Decoction on α-SMA and collagen synthesis in rat myocardial fibroblasts induced by transforming growth factor-β_(1)

Objective:To explore the protective effect of Linggui Zhugan Decoction(LGZGD)medicated serum on myocardial fibrosis induced by transforming growth factor-β1(TGF-β1).Methods:Using enzyme digestion method,combined with differential adherence to isolate and culture Sprague-Dawley(SD)suckling mouse Cardiac fibroblasys(CFB)in vitro.Divided into:blank group,blank rat serum group,model group,and LGZGD medicated serum group(5%、10%、20%).Except for blank group and blank rat serum group,they were stimulated with 5 ng/ml TGF-β1 for 12 hours,and then then intervene with LGZGD medicated serum(5%、10%、20%)and continue to culture for 24 hours.Use immunofluorescence and Western blot(WB)to detect the expression ofα-smooth muscle actin(α-SMA),Enzyme-linked immunosorbent assay(ELISA)and WB to detect type Ⅰ collagen(Collagen Ⅰ),type Ⅰ collagen(Collagen Ⅲ)and fibronectin(FN)expression.Results:Compared with the blank group,the expressions of Collagen Ⅰ,Collagen Ⅲ,α-SMA and FN in the model group were significantly increased(P<0.01);Compared with the model group,the expressions of Collagen Ⅰ and Collagen Ⅲ in each concentration group of the experiment were significantly reduced(P<0.01);the expression ofα-SMA and FN were significantly reduced(P<0.01).Conclusions:LGZGD has an inhibitory effect on collagen synthesis and the expression ofα-SMA and FN,indicating that the anti-fibrosis effect of LGZGD is related to it.

Vascular endothelial growth factor A, secreted in response to transforming growth factor-β1 under hypoxic conditions, induces autocrine effects on migration of prostate cancer cells

Hypoxia and transforming growth factor-β1 （TGF-β1） increase vascular endothelial growth factor A （VEGFA） expression in a number of malignancies. This effect of hypoxia and TGF-β1 might be responsible for tumor progression and metastasis of advanced prostate cancer. In the present study, TGF-β1 was shown to induce VEGFA165 secretion from both normal cell lines （HPV7 and RWPE1） and prostate cancer cell lines （DU 145 and PC3）. Conversely, hypoxia-stimulated VEGFA165 secretion was observed only in prostate cancer cell lines. Hypoxia induced TGF-β1 expression in PC3 prostate cancer cells, and the TGF-β1 type I receptor （ALK5） kinase inhibitor partially blocked hypoxia-mediated VEGFA16s secretion. This effect of hypoxia provides a novel mechanism to increase VEGFA expression in prostate cancer cells. Although autocrine signaling of VEGFA has been implicated in prostate cancer progression and metastasis, the associated mechanism is poorly characterized. VEGFA activity is mediated via VEGF receptor （VEGFR） 1 （Fit-l） and 2 （FIk-I/KDR）. Whereas VEGFR-1 mRNA was detected in normal prostate epithelial cells, VEGFR-2 mRNA and VEGFR protein were expressed only in PC3 cells. VEGFA165 treatment induced phosphorylation of extracellular signal-regulated kinase 1/2 （ERKI/2） in PC3 cells but not in HPV7 cells, suggesting that the autocrine function of VEGFA may be uniquely associated with prostate cancer. Activation of VEGFR-2 by VEGFA165 was shown to enhance migration of PC3 cells. A similar effect was also observed with endogenous VEGFA induced by TGF-β1 and hypoxia. These findings illustrate that an autocrine loop of VEGFA via VEGFR-2 is critical for the tumorigenic effects of TGF-β1 and hypoxia on metastatic prostate cancers.

The Effect of Simvastatin on mRNA Expression of Transforming Growth Factor-β1,Bone Morphogenetic Protein-2 and Vascular Endothelial Growth Factor in Tooth Extraction Socket

Aim To determine the effect of local simvastatin application on the mRNA expression level of transforming growth factor-β1 （TGF-β1）, bone morphogenetic protein-2 （BMP-2） and vascular endothelial growth factor （VEGF） in the tooth sockets of rat. Methodology Forty-eight male Wistar rats were randomly divided into experimental and control groups （n=24）. Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The expression of TGF-β1, BMP-2 and VEGF mRNA was determined by in situ hybridization in the tooth extraction socket at five days, one week, two weeks and four weeks after implantation. Results The fusiform stroma cells in the tooth extraction socket began to express TGF-β1, BMP-2 and VEGF mRNA in both experimental and control groups from one week after tooth extraction until the end of experiment. The expression of TGF-131 and BMP-2 mRNA in the experimental group was significantly up-regulated after one, two and four weeks, and expression of VEGF mRNA was significantly increased after one and two weeks compared with that in the control group. Conclusion The findings indicate that local administration of simvastatin can influence alveolar bone remodeling by regulating the expression of a school of growth factors which are crucial to osteogenesis in the tooth extraction socket.

Effect of β radiation on TGF-β_1 and bFGF expression in hyperplastic prostatic tissues

Aim: To investigate the transforming growth factor β_1 (TGF-β_1) and basic fibroblast growth factor (bFGF) expressions in benign prostatic hyperplasia (BPH) and the effect of β-radiation. Methods: TGF-β_1 and bFGF expression was studied by means of an immunohistochemical method in nine normal prostatic (NP) tissues, 15 hyperplastic prostatic tissues and 35 hyperplastic prostatic tissues treated with ^(90)Sr/^(90)Y. Results: The TGF-β_1 expression in the epithelium and stroma of normal prostatic tissues was 68.2 % ± 10.5 % and 29.7 % ± 4.6 %, respectively, while it was 64.8 % ± 9.3 % and 28.6 % ± 4.1%, respectively, in hyperplastic prostatic tissues. Compared with the controls, TGF-β_1 expression in the epithelia and stroma of BPH treated with ^(90)Sr/^(90)Y increased significantly (P < 0.01). The bFGF expression in epithelia and stroma of normal prostatic tissues was 17.4 % ± 3.7 % and 42.5 % ± 6.8 %, respectively, and was 46.3 % ± 8.2 % and 73.2 % ± 12.1%, respectivley, in hyperplastic prostatic tissues. Compared with the controls, expressions of bFGFin the epithelia and stroma of BPH treated with a ^(90)Sr/^(90)Y prostatic hyperplasia applicator decreased significantly (P < 0.01). Conclusion: Exposure of β-rays had noticeable effects on BPH tissues, enhancing TGF-β_1 expression and inhibiting bFGF expression.

Colonic expression of Runx3 protein and TGF-β_1 and their correlation in patients with irritable bowel syndrome

Objective:To investigate the role of Runx3 protein and TGF-β_1 in the pathogenesis of irritable bowel syndrome(IBS),as well as the correlation of these two proteins.Methods:Colonic tissue was collected from patients with IBS and normal persons.The colonic expression of Runx3 protein and TGF-β_1 was detected with immunohislochemistry method.Semi-quantitative analysis was used to evaluate the staining degree of these two proteins.Results:Compared with their counterparts,patients with IBS did not show any changes in the colonic expression of Runx3 protein and TGF-β_1(P>0.05).Interestingly,there was a significant correlation between Runx3 protein and TGF-β_1 in patients with IBS(P<0.05).Conclusions:The role of Runx3 protein and TGF-β_1 in the pathogenesis of IBS remains to be further studied.

Genetic expression of Col-2A and Col-10A as a function of administration of IGF-1 &TGF-<i>β</i>with and without anterior mandibular repositioning appliance on the growth of mandibular condylar cartilage in young rabbit

New Zealand (NZ) young rabbits with the administration of insulin-like growth factor (IGF-1) and transforming growth factor-β (TGF-β) with and without mandibular anterior repositioning appliances are explored for the growth of the mandibular condylar cartilage (MCC). 32 growing NZ and rabbits were divided into 4 groups: the group with saline injection in TMJ, the group which received growth factor injection in TMJ, the group which received anterior positioning appliance and the group which received growth factors injection as well as mandibular repositioning appliance. Gene expression was studied by real-time RT-PCR and cartilage growth by histomorphometry. Administration of growth factors along with mandibular repositioning appliances has induced 1) 1.70-fold expression of Col-2Agene (p value < 0.0005) and 2) 1.47-fold expression of Col-10Agene (p value < 0.0005). In contrast, administration of only mandibular repositioning appliances induced 1) 1.28-fold expression of Col-2Agene (p value < 0.0005) and 2) merely 0.62-fold expression of Col-10Agene (p value < 0.0005), while administration of growth factors only induced 1) mere 0.56-fold expression of Col-2Agene (p value 10A gene (p value growth factors along with mandibular repositioning appliances causes an increase in genetic expressions which have been corroborated by histomorphometry and validated by statistical analysis, during an accelerated growth of mandibular condylar cartilage. Administration of growth factors in the TMJ could provide a synergistic role along with mandibular repositioning appliances for treatment of mandibular retrognathism as well as disorders on the MCC.

外周血及大肠癌组织TGF-β1含量检测及临床意义

目的探讨转化生长因子(TGF-β1)在结直肠癌患者的表达情况及临床意义。方法采用ELISA方法检测50例结直肠癌患者术前、术后,以及25例健康志愿者的外周血TGF-β1表达水平差异,同时检测了结直肠癌肿瘤组织和癌旁正常大肠组织匀浆上清的TGF-β1含量,分析TGF-β1浓度的变化与临床病理指标的关系。结果结直肠癌患者术前血浆TGF-β1水平明显高于术后组以及健康对照组,差异有统计学意义(P<0.05);肿瘤组织TGF-β1含量显著高于癌旁正常大肠组织(P<0.05);在CEA阴性及CEA阳性患者中均可分别观察到类似的浓度改变。外周血TGF-β1水平与肿瘤大小呈正相关,随着肿瘤分期的进展,浓度明显升高。结论 TGF-β1可联合CEA检测,更好的为结直肠癌的临床诊断、评价预后和复发提供参考价值,同时为基于抗TGF-β1的肿瘤免疫治疗提供参考依据。

Effects of angiotensin Ⅱ receptor antagonist on expression of collagen Ⅲ,collagen Ⅴ,and transforming growth factor β_1 in the airway walls of sensitized rats

Background Repeated attacks of bronchial asthma lead to different degrees of airway remodeling,the mechanism of which is not yet clear. Some evidences indicate that it is related to the excessive expression of some growth promotion factors. Angiotensin Ⅱ is a polypeptide that may be involved in airway remodeling. To evaluate its role in airway remodeling in asthma,we observed the effects of an angiotensin Ⅱ type 1 receptor antagonist (valsartan) on the expression of collagen Ⅲ,collagen Ⅴ,and transforming growth factor β_1 (TGF-β_1) mRNA and protein in the airway walls of sensitized rats.Methods Forty Wistar rats were randomly divided into 5 groups: control group,sensitized group,and valsartan groups 1,2,and 3. The rats in the sensitized group and in valsartan groups 1,2,and 3 were sensitized and challenged with ovalbumin. Rats in control group were sensitized and challenged with 0.9% NaCl. Rats from valsartan groups 1,2,and 3 were drenched with valsartan (10 μg, 20 μg,or 30 μg,respectively) at the time of the ovalbumin challenges. The expression of collagen Ⅲ,collagen Ⅴ,and TGF-β_1 protein were detected using immunohistochemical method in combination with image analysis methods. The expression of TGF-β_1 mRNA was detected by in situ hybridization. Results The expression in the airways of collagen Ⅲ and collagen Ⅴ was significantly higher in rats from the sensitized group (7.73±0.81, 1.34±0.28) and from valsartan groups 1,2,and 3 (5.73±0.64, 1.13±0.15; 4.96±0.51, 0.98±0.08; 4.43±0.35, 0.93±0.06,respectively) than those in the control group (2.65±0.38, 0.67±0.08,P <0.05). In addition,collagen levels were significantly lower in valsartan groups 1,2,and 3 than those from the sensitized group ( P <0.05). The expression of TGF-β_1 mRNA and protein in the airways was significantly higher in rats from the sensitized group (20.49%±3.46%,29.73%±3.25%) and from valsartan groups 1,2,and 3 (16.47%±1.94%, 19.41%±1.87%; 14.38%±1.58%, 18.29%±1.43%; 12.96%±1.73%, 18.63%±1.11%,respectively) than that from the control group (7.84%±1.61%, 5.63%±1.07%,P <0.05). TGF-β_1 mRNA and protein levels were significantly lower in valsartan groups 1,2,and 3 than that in the sensitized group ( P <0.05). Conclusions Angiotensin Ⅱ receptor antagonist valsartan can suppress synthesis of collagen Ⅲ and collagen Ⅴ by downregulating TGF-β_1 mRNA and protein expression. Valsartan can decrease airway remodeling and could play a role in asthma therapy.

Concentration change of TGF-β1 in aqueous humor of rabbits

Objective:To observe the influence of the the transforming growth factorβ1(TGF-β1)eve drops on rabbit aqueous humor TGF-β1 concentration,and to analyze the best drug concentration.Methods:A total of 30 New Zealand white rabbits were randomly divided into5 groups with 6 in each.Habits in control group had PBS eye drops,group A,B.C,D adopted TGF-β1 eye drops at 0.5,1.0.2.0.4.0 mg/L,respectively.4 times a day.Aqueous humor of right eye was extracted 1 week after administration lo delect concentration changes of TGF-β1 by ELISA;rabbits in fpur hroups adopted 2.0 mg/L eye drops to left eyes 4 times a day,0.2 mL aqueous humor was extracted left eye at the scheduled time point 0,30 min,2 h,4 h,24 h for testing,the slit lamp was used to observe the cornea,chamber and lens.Results:No obvious pathological changes in conjunctiva,cornea,rabbit conjunctival,anterior chamber,and the lens was found.Concentration of TGF-β1 in rabbit aqueous humor in C.D group was significantly higher than the control group(P<0.05).Conclusions:TGF-β1 eye drops at 2.0 mg/L.4.0 mg/L can significantly increase concentration of TGF-β1 in rabbit aqueous humor,withe good ocular surfac permeability.

Astragalus mongholicus ameliorates renal fibrosis by modulating HGF and TGF-β in rats with unilateral ureteral obstruction

Astragalus mongholicus （AM） derived from the dry root ofAstragalus membranaceus Bge. var. mongolicus （Bge.） Hsiao is a widely used traditional Chinese medicine. The present study investigated the potential role of AM on renal fibrosis on a rat model of unilateral ureteral obstruction （UUO）. We divided 48 Sprague-Dawley rats randomly into 4 groups： sham-operated group （Sham）, untreated UUO group, AM-treated （10 g/（kg.d）） UUO group, and losartan-treated （20 mg/（kg.d）） UUO group as positive control. Haematoxylin ＆ eosin （HE） and Masson staining were used to study the dynamic histological changes of the kidneys 7 and 14 d after operation. The expressions of fibronectin （FN）, type I collagen （coil）, hepatocyte growth factor （HGF）, transforming growth factor-β1 （TGF-β1）, and eL-smooth muscle actin （α-SMA） were analyzed by real-time polymerase chain reaction （PCR）, immunohistochemistry staining, and Western blot. Results show that, similar to losartan, AM alleviated the renal damage and decreased the deposition of FN and coil from UUO by reducing the expressions of TGF-β1 and α-SMA （P〈0.05）, whereas HGF increased greatly with AM treatment （P〈0.05）. Our findings reveal that AM could retard the progression of renal fibrosis. The renoprotective effect of AM might be related to inhibition ofmyofibroblast activation, inducing of HGF and reducing of TGF-β1 expression.

Protective effect of dihydropteridine reductase against oxidative stress is abolished with A278C mutation

Objective: To evaluate the antioxidation of dihydrobiopterin reductase and to explore the effect of A278C mutation of the quinoid dihydropteridine reductase(QDPR) gene on its antioxidant activity. Methods: First, plasmids with different genes(wild and mutant QDPR) were constructed. After gene sequencing, they were transfected into human kidney cells(HEK293T). Then, the intracellular production of reactive oxygen species(ROS) and tetrahydrobiopterin(BH4) was detected after cells were harvested. Activations of nicotinamide adenine dinucleotide phosphate oxidase 4(NOX4), glutathione peroxidase 3(GPX3), and superoxide dismutase 1(SOD1) were analyzed to observe the oxidative stress after transfection. The expression of the neuronal nitric oxide synthase(n NOS) gene was analyzed by semiquantitative reverse-transcription polymerase chain reaction(RT-PCR). We also detected the activation of transforming growth factor β1(TGF-β1) by enzyme-linked immunosorbent assay(ELISA) to observe the connection of TGF-β1 and oxidative stress. Results: The exogenous wild-type QDPR significantly decreased the expression of n NOS, NOX4, and TGF-β1 and induced the expression of SOD1 and GPX3, but the mutated QDPR lost this function and resulted in excessive ROS production. Our data also suggested that the influence on the level of BH4 had no significant difference between mutated and the wild-type QDPR transfection. Conclusions: Wild-type QDPR played an important role in protecting against oxidative stress, but mutant QDPR failed to have these beneficial effects.