TGF-beta1 mRNA Expression Research Articles

TGF-β1 RNA Interference in Mouse Primary Dura Cell Culture: Downstream Effects on TGF Receptors, FGF-2, and FGF-R1 mRNA Levels

Transforming growth factor (TGF)-beta1 and fibroblast growth factor (FGF)-2 have both been shown to have significant roles in the regulation of murine calvarial suture fusion. Methods to decrease gene expression of these cytokines and their respective receptors have been established, but because of side effects, clinical applications are limited. In this study, the authors examined the effect of TGF-beta1-specific small interfering RNA (siRNA) on the messenger RNA (mRNA) expression of TGF-beta1, its TGF-betaR1 and TGF-betaR2 receptors, and FGF-2 and its R1 receptor in murine dura cells. A primary dura cell line was established from CD-1 mice. Transfection efficiency using Lipofectamine was determined using BLOCKiT. Dura cells were transfected with serial concentrations of TGF-beta1 siRNA to determine the optimal dose. In subsequent experiments, cells were transfected with 16 nM TGF-beta1 siRNA and harvested on posttransfection days 4, 7, 10, and 14 for RNA isolation and quantitative polymerase chain reaction. Optimal inhibition of TGF-beta1 mRNA expression was achieved at 16 nM siRNA. On posttransfection day 4, TGF-beta1 mRNA levels were significantly decreased but returned to baseline by day 14. TGF-betaR1 mRNA expression remained unaffected by transfection throughout the time course. However, TGF-betaR2, FGF-2, and FGF-R1 demonstrated significant inhibition of mRNA expression on posttransfection day 4. These results indicate that TGF-beta1 siRNA has the potential to alter the murine dura cytokines responsible for suture fusion in vitro. Manipulating underlying cranial suture biology with siRNA technology may ultimately allow control over suture fusion. This intervention may ultimately function as an effective adjunct to surgical intervention for craniosynostosis.

Hepatocyte Growth Factor Suppresses Transforming Growth Factor-Beta-1 and Type III Collagen in Human Primary Renal Fibroblasts

Tubulointerstitial changes in the diabetic kidney correlate closely with renal fibrosis, and transforming growth factor-beta-1 (TGF-beta1) is thought to play a key role in this process. In contrast, hepatocyte growth factor (HGF) has shown therapeutic effects on injured renal tubules in animal models. This study was undertaken to test the hypothesis that the preventive effects of HGF may result from interventions in TGF-beta1-mediated signaling and collagen III secretion. We examined the expression of HGF/HGF receptor (c-Met) and TGF-beta1 in renal fibroblasts at multiple time points. The effects of recombinant human HGF on TGF-beta1 expression were studied by RT-PCR and Western blotting, and the levels of collagen III were measured by ELISA. In the high-glucose condition, the expression of HGF and c-Met in renal fibroblasts was detected as early as 6 hours following cell culture while the level of TGF-beta1 peaked at 96 hours. The addition of recombinant human HGF to the culture media dose-dependently inhibited TGF-beta1 mRNA expression and reduced collagen III secretion by 34%. These results indicate that, during hyperglycemia, HGF inhibits TGF-beta1 signaling and type III collagen activation in interstitial fibroblasts. Furthermore, we should recognize that changes in the balance between HGF and TGF-beta1 might be decisive in the pathogenesis of chronic renal fibrosis. Therefore, administration of HGF to restore this balance may offer a novel therapeutic intervention in managing renal fibrogenesis in diabetic nephropathy.

CD4 T cell subsets in the mucosa are CD28+Ki‐67−HLA‐DR−CD69+ but show differential infection based on α4β7 receptor expression during acute SIV infection

CD4 T cell depletion in the mucosa has been well documented during acute HIV and SIV infections. The demonstration the HIV/SIVcan use the alpha4beta7 receptor for viral entry suggests that these viruses selectively target CD4 T cells in the mucosa that express high levels of alpha4beta7 receptor. Mucosal samples obtained from SIV infected rhesus macaques during the early phase of infection were used for immunophenotypic analysis. CD4 T cell subsets were sorted based on the expression of beta7 and CD95 to quantify the level of SIV infection in different subsets of CD4 T cells. Changes in IL-17, IL-21, IL-23 and TGFbeta mRNA expression was determined using Taqman PCR. CD4 T cells in the mucosa were found to harbor two major population of cells; -25% of CD4 T cells expressed the alpha4(+)beta7(hi) phenotype, whereas the rest of the 75% expressed an alpha4(+)beta7(int) phenotype. Both the subsets were predominantly CD28(+)Ki-67(-)HLA-DR(-) but CD69(+), and expressed detectable levels of CCR5 on their surface. Interestingly, however, alpha4(+)beta7(hi)CD4 T cells were found to harbor more SIV than the alpha4(+)beta7(int) subsets at day 10 pi. Early infection was associated with a dramatic increase in the expression of IL-17, and IL-17 promoting cytokines IL-21, IL-23, and TGFbeta that stayed high even after the loss of mucosal CD4 T cells. Our results suggest that the differential expression of the alpha4beta7 receptor contributes to the differences in the extent of infection in CD4 T cell subsets in the mucosa. Early infection is associated dysregulation of the IL-17 network in mucosal tissues involves other non-Th-17 cells that likely contributes to the pro-inflammatory environment in the mucosa during acute stages of SIV infection.

PPARα Ligand WY14643 Reduced Acute Rejection After Rat Lung Transplantation With The Upregulation of IL-4, IL-10 and TGFβ mRNA Expression

The peroxisome proliferators-activated receptor-alpha (PPARalpha) is important in lipid metabolism and regulation of inflammation. Recent studies have demonstrated the immunoregulatory effects of PPARalpha. This investigated the immunosuppressive effects of PPARalpha using its ligand, WY14643, on acute lung allograft rejection in a rat model and its mechanism of action. The left lungs were transplanted orthotopically from Brown-Norway donors to F344 recipients. The recipients were then divided into control and WY14643 treatment groups. The allograft rejection was evaluated by daily chest X-ray imaging and was evaluated histologically on Day 7 after transplantation. The cytokine messenger RNA (mRNA) expression at Days 3 and 5 were also evaluated in allografts and recipient spleens. The radiologic and histologic findings indicated that treatment with the WY14643 reduced acute allograft rejection. WY14643 also significantly extended the allograft survival time. This amelioration of acute rejection by WY14643 was also associated with up-regulated interleukin (IL)-4, IL-10, and transforming growth factor-beta (TGFbeta) mRNA expression in the lung allografts and spleens. This study demonstrated that the administration of the PPARa ligand, WY14643, ameliorates acute lung allograft rejection in rats. Treatment with WY14643 reduced histopathologic scores, prolonged graft survival, and up-regulated the expression of anti-inflammatory cytokine IL-4, IL-10, and TGFbeta mRNA compared with the control.

Intratracheal instillation of bone marrow-derived cell in an experimental model of silicosis

The time course of lung mechanics, histology, and inflammatory and fibrogenic mediators are analysed after intratracheal instillation (IT) of bone marrow-derived cells (BMDC) in a model of silicosis. C57BL/6 mice were randomly divided into SIL (silica, 20mg IT) and control (CTRL) groups (saline IT). At day 15, mice received saline or BMDC (2 x 10(6)cells) IT. The biodistribution of technetium-99m BMDC was higher in lungs compared with other organs. At days 30 and 60, lung mechanics, the area of granulomatous nodules, and mRNA expression of IL-1beta and TGF-beta were higher in SIL than CTRL animals. BMDC minimized changes in lung mechanics, the area of granulomatous nodules, and total cell infiltration at day 30, but these effects were no longer observed at day 60. Conversely, BMDC avoided the expression of IL-1beta at days 30 and 60 and TGF-beta only at day 30. In conclusion, BMDC therapy improved lung mechanics and histology, but this beneficial effect was not maintained in the course of injury.

Anti-fibrotic effect of thalidomide through inhibiting TGF-β-induced ERK1/2 pathways in bleomycin-induced lung fibrosis in mice

This study is designed to confirm the anti-fibrotic effect of thalidomide on bleomycin-induced lung fibrosis in a mouse model and to identify whether this anti-fibrotic effect is associated with inhibition of the transforming growth factor-beta (TGF-beta)-induced extracellular signal-regulated kinase1/2 (ERK1/2). C57BL/6 female mice were administered blomycin sulfate. In cultured human lung fibroblasts, expressions of type I collagen, fibronectin, and either TGF-beta or IL-6 were measured after thalidomide treatment by reverse transcription-polymerase chain reaction (RT-PCR). Expressions of ERK1/2, type I collagen, fibronectin, and TGF-beta1 from lung tissues of blomycin-induced mice and from mouse lung fibroblasts were evaluated using RT-PCR and western blotting. Thalidomide administration significantly inhibits TGF-beta1 mRNA expression in a dose-dependant manner following administration of IL-6 and IL-6R. In the analysis of BAL fluids, total BAL inflammatory cell counts, TGF-beta1, and IL-6 levels in thalidomide-treated mice were significantly reduced when compared with bleomycin-treated mice (p < 0.01, p < 0.01, and p < 0.001, respectively). Thalidomide inhibited total ERK1/2 and phospho-ERK1/2 expression after TGF-beta1 stimulation in the RT-PCR and western blotting. The results of our study suggest that the anti-fibrotic effect of thalidomide on lung fibrosis may be related to suppression of the TGF-beta1-induced ERK1/2 signaling pathway.

Expression of TGF-beta1 and the mechanism of invasiveness and metastasis induced by TGF-beta1 in breast cancer

To investigate the expression of MMP-2, TIMP-2, TGF-beta1 and TGF-betaRI and the relationship among them in breast cancer. The protein expression of MMP-2, TIMP-2, TGF-beta1 and TGF-betaRI was detected on tissue chips by S-P immunohistochemical staining in 160 cases of breast carcinoma. The positive rates of TGF-beta1, TGF-beta1 mRNA, MMP-2, MMP-9, TIMP-1 and TIMP-2 expression were 73.7%, 56.2%, 96.9%, 95.0%, 87.5% and 89.4%, respectively. Axillary lymph node metastasis and TNM staging (P < 0.01 and P < 0.01, respectively) were positively correlated to the expression of TGF-beta1. Relase-free survival of TGF-beta1 positive group was lower than that of TGF-beta1 negative group (P = 0.023). The expression of MMP-2 or MMP-9 was positively correlated to that of TGF-beta1 (r = 0.170, P < 0.05; r = 0.221, P < 0.01) and was negatively correlated to that of TGF-beta1 mRNA (r = -0.126, P > 0.05;r = 0.019, P > 0.05). The expression of TGF-beta1 may be closely correlated with the invasion and metastasis of breast cancer. TGF-beta1-induced invasiveness and metastasis of breast cancer cells are mediated by MMP-2 and MMP-9.

Renoprotective effects of an angiotensin II receptor blocker in experimental model rats with hypertension and metabolic disorders

Metabolic syndrome (MS) is an independent risk factor for chronic kidney diseases. As the renin-angiotensin system (RAS) is known to have a key role in renal damage, blockade of RAS may show renoprotective effects in MS. In this study, we investigated the renoprotective effects and mechanisms of action of an angiotensin receptor blocker (ARB) in spontaneously hypertensive (SHR/NDmcr-cp) rats as a model of MS. Male SHR/NDmcr-cp rats at 9 weeks of age were divided into three groups, each of which was treated for 12 weeks with vehicle, hydralazine (7.5 mg kg(-1) per day, p.o.) or ARB (olmesartan, 5 mg kg(-1) per day, p.o.). Blood pressure and urinary protein (UP) excretion were monitored. Kidney tissues were subjected to histological, immunohistochemical and molecular analyses. UP excretion increased with age in vehicle-treated SHR/NDmcr-cp rats compared with that in age-matched WKY/Izm rats. In addition, there was significant glomerular damage (increased glomerular sclerosis index, desmin staining and proliferating cell nuclear antigen (PCNA)-positive cells, electron microscopic findings of podocyte injury) and tubulointerstitial damage (increased tubulointerstitial fibrosis index, type IV collagen staining, PCNA-positive cells and expression of TGF-beta mRNA) in vehicle-treated SHR/NDmcr-cp rats compared with that in control rats. All the findings that related to glomerular and tubulointerstitial damage were significantly improved by ARB. Hydralazine mitigated the observed renal damage but was much less effective than ARB, despite similar decreases in blood pressure. There were no significant differences in glucose and lipid metabolism among vehicle-treated, hydralazine-treated and ARB-treated SHR/NDmcr-cp animals. These data suggest that RAS is deeply involved in the pathogenesis of renal damage in MS, and ARBs could provide a powerful renoprotective regimen for patients with MS.

Peroxisome proliferator-activated receptor-γ (PPAR-γ) agonist inhibits transforming growth factor-beta1 and matrix production in human dermal fibroblasts

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonists are increasingly used in patients with diabetes, and some studies have suggested a beneficial effect on organ fibrosis, but their effects on dermal cell growth and extracellular matrix (ECM) turnover are unknown. To investigate the effect of the PPAR-gamma agonist troglitazone on cell growth and matrix production in human dermal fibroblasts (HDF), HDF were cultured and grown in a different concentration of troglitazone. PPAR-gamma expression and matrix production were measured in HDF in the presence of troglitazone. The mRNA expressions of TGF-beta1, collagen I (Col I) and fibronectin (FN) were determined by quantitative real-time reverse transcription polymerase chain reaction (RT-PCR). The protein of transforming growth factor-beta1 (TGF-beta1) was determined by enzyme-linked immunosorbent assay (ELISA) and proteins of Col I and FN were determined by Western blotting. The mRNA expression of TGF-beta1, Col I and FN were significantly decreased in HDF in 15-30 micromol l(-1) troglitazone compared to the control group with Dulbecco's modified Eagle's medium (P<0.01). An obvious decrease of TGF-beta1 protein was found in troglitazone-treated groups as compared to the control group (P<0.05). Exposure of HDF to troglitazone reduced col I secretion (P<0.05), and fibronectin secretion (P<0.05). This study suggests that PPAR-gamma agonist will provide a novel approach with therapeutic potential in dermal fibrosis, such as hypertrophic scar, keloid and so on.

Effect of Transdermal Electromotive Drug Therapy on Fibrogenic Cytokine Expression in Peyronie's Disease

To assess the effect of transdermal electromotive drug therapy (EMDT) on transforming growth factor-beta (TGF-beta) and basic fibroblast growth factor (bFGF) expression and their receptors in plaques in patients with Peyronie's disease. Tissue was obtained from 13 patients with stable Peyronie's disease who had undergone plaque excision because of penile curvature. Of the 13 patients, 7 underwent EMDT with dexamethasone, verapamil, and lidocaine as first-line therapy before plaque excision and 6 were therapy naive. TGF-beta and bFGF mRNA and protein expression and that of their receptors were measured using real-time polymerase chain reaction and Western blotting. The mean patient age was 52.83 years. The mean interval from the end of EMDT to plaque excision was 7.6 months, with stable disease for >or=5 months. The comparison of TGF-beta mRNA expression in the plaques showed no difference between the EMDT and therapy-naive patients (P = .17). Also, TGF-beta protein expression in the plaques was not significantly different between the EMDT and therapy-naive patients (P = .443). TGF-beta receptor 1 mRNA expression in the plaques was significantly different between the EMDT and therapy-naive patients (P = .023), but no difference was found for TGF-beta receptor 2 mRNA (P = .292). The expression of bFGF mRNA (P = .0005) and bFGF protein expression (P = .034) in the plaques was significantly lower after EMDT. bFGF receptor mRNA expression (P = .619) showed no significant differences. Patients with Peyronie's had significantly lower bFGF mRNA and bFGF protein expression in the plaques after EMDT. Also, overexpression of TGF-beta protein and the TGF-beta receptor was identified in the EMDT plaques compared with the therapy-naive plaques.

Antifibrotic effects of N-acetyl-seryl-aspartyl-lysyl-proline mediated by regulation of transforming growth factor beta and connective tissue growth factor expression on rats with silicosis

To investigate whether the effect of N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP) on transforming growth factor beta (TGF-beta1) and connective tissues growth factor (CTGF) was involved in AcSDKP's antifibrotic effect on the rats with silicosis. Rats were divided into 6 groups randomly, 10 rats in each group: Control of silicotic model: 1.0 ml normal sodium and was killed after 4 or 8 weeks; Silicotic model 1: 50 mg/ml silica suspension and was killed after 4 weeks; Silicotic model 2: 50 mg/ml silica suspension and was killed after 8 weeks; Anti-fibrosis treatment of AcSDKP: after each rat was intratracheally instilled with 50 mg/ml silica suspension for 4 weeks, AcSDKP 800 microg/(kg x d) was administered into every rat and rats were killed at the 8 weeks; Preventing fibrosis treatment of AcSDKP: after AcSDKP [800 microg/(kg x d)] was administered into every rat for 48 hours, each rat was intratracheally instilled with 50 mg/ml silica suspension and rats were killed at the 8 weeks. Lung fibrosis in morphology was observed by HE staining. The expressions of TGF-beta1 and CTGF in lung were observed by immunohistochemistry. The mRNA expressions of TGF-beta1 and CTGF in lung were observed by real-time PCR. In anti-fibrosis treatment of AcSDKP group, protein expression of TGF-beta1 and CTGF were (0.244 +/- 0.016) and (0.241 +/- 0.017) respectively, and significantly lower that those in the silicotic model 1 and 2 groups; mRNA expressions of TGF-beta1 and CTGF decreased, mRNA expressions of CTGF were significantly lower that those in the silicotic model 1 and 2 groups (P < 0.05); In preventing fibrosis treatment of AcSDKP group, protein expression and mRNA expression of TGF-beta1 were significantly lower that those in the silicotic model 2 group (P < 0.05). AcSDKP can decrease the expressions of TGF-beta1 and CTGF in lung tissues of the rats with experimentally induced pulmonary fibrosis.

Decreased Expression of Thrombospondin-1 in Failing Hearts May Favor Ventricular Remodeling

Thrombospondin-1 (TSP-1) is a potent inhibitor of angiogenesis and an activator of tissue transforming growth factor-beta1 (TGF-beta1). Analyses using genetically modified mice suggested that TSP-1 may play a protective role to prevent infiltration and tissue remodeling responses after myocardial infarction. The expression levels of TSP-1 and their putative role in ventricular remodeling have not been determined in patients with heart failure (HF). We analyzed the expression of TSP-1 and TGF-beta1 mRNA in myocardial biopsies from 34 subjects with end-stage HF undergoing heart transplantation and 13 healthy controls from heart donors. Among total RNA extracted from the left ventricle, 1 microg was retrotranscribed and mRNA expression levels were quantified by real-time polymerase chain reaction (PCR). The mean age of subjects was 54 +/- 2 years; mean ejection fraction, 21 +/- 5%; end-diastolic diameter and end-systolic diameter, 73 +/- 10 and 61 +/- 11 mm, respectively. TSP-1 mRNA expression in ventricular tissue from HF patients was lower (159.04 +/- 14.55 ng-equivalents [ng-equiv]) than in controls (234 +/- 30.66 ng-equiv; P < .05). Tissue from HF subjects also showed lower levels of TGF-beta1 (68.42 +/- 4.36 vs 80.58 +/- 5.26 ng-equiv; P < .05). TSP-1 mRNA levels correlated positively with TGF-beta1 (P = .001; R(2) = .2), and lower TSP-1 mRNA levels were observed with increasing left ventricular diameters. Patients with end-stage HF show decreased TSP-1 mRNA levels, which agrees with published results showing lower circulating TSP-1. Ventricular dilatation observed in these patients may be related to lower expression of TSP-1. Surprisingly, TGF-beta1 mRNA levels were lower in failing hearts, which suggested that fibrogenesis takes place in earlier phases of HF.

Differential role of mesangial cells and podocytes in TGF-beta-induced mesangial matrix synthesis in chronic glomerular disease.

Glomerulosclerosis is characterized by mesangial matrix accumulation that is mediated primarily by activation of transforming growth factor-beta (TGF-beta). Unlike podocytes, mesangial cells secrete TGF-beta in response to common in vitro fibrogenic stimuli. However, mesangial immunostaining for active TGF-beta1 in chronic glomerular disease is almost negligible, despite increased mesangial TGF-beta1 mRNA expression, while podocytes covering the sclerotic glomerular segments exhibit increased TGF-beta1 protein expression. The mechanisms whereby TGF-beta is activated in the diseased glomeruli and how the activated TGF-beta leads to mesangial matrix overproduction are not clear. We provide evidence that TGF-beta secreted as latent complexes by mesangial cells is stored in the mesangial matrix, from which soluble forms of latent TGF-beta are released and localized to the podocyte surface in chronic glomerular disease. Podocyte-derived reactive oxygen species, plasmin and thrombospondin-1, particularly renin-angiotensin-aldosterone system-induced oxidative stress, seem to be involved in TGF-beta activation in podocytes. We also provide evidence that the TGF-beta-induced secretion of connective tissue growth factor and vascular endothelial growth factor by podocytes acts as a paracrine regulatory mechanism on mesangial cells, which may cause mesangial matrix accumulation culminating in the development of glomerulosclerosis. Collectively, these data bring new insights into our understanding of the roles of the mesangial cells and podocytes in the TGF-beta-induced mesangial matrix synthesis in chronic glomerular disease.

Impaired cutaneous wound healing with excess granulation tissue formation in TNFα-null mice

We examined the effects of lacking tumor necrosis factor alpha (TNFalpha) on the healing process of a cutaneous wound in mice using TNFalpha-deficient mice. A full-thickness circular cutaneous wound 5.0 mm in diameter was produced in the dorsal skin of wild-type (WT) or TNFalpha-null (KO) mice. After specific intervals of healing, the healing pattern was evaluated by macroscopic observation, histology, immunohistochemistry, or real-time reverse transcription-polymerase chain reaction. Effect of Smad7 gene transfer on the healing phenotype of KO mice was also examined. The results showed that loss of TNFalpha promotes granulation tissue formation and retards reepithelialization in a circular wound in mouse dorsal skin. Immunohistochemistry showed that distribution of macrophages and myofibroblasts in newly generated granulation tissue seemed similar between WT and KO mice. However, lacking TNFalpha enhanced mRNA expression of TGFbeta1 and collagen Ialpha2 in such tissue. Smad7 gene transfer counteracted excess granulation tissue formation in KO mice. In conclusion, lacking TNFalpha potentiates Smad-mediated fibrogenic reaction in healing dermis and retards reepithelialization in a healing mouse cutaneous wound.

Dietary olive oil prevents carbon tetrachloride-induced hepatic fibrosis in mice

The specific purpose of this study was to investigate the effects of dietary olive oil on hepatic fibrosis induced by chronic administration of carbon tetrachloride (CCl(4)) in the mouse. In addition, the effects of oleic acid, a major component of olive oil, on activation of hepatic stellate cells (HSCs) were investigated in vitro. Mice were fed liquid diets containing either corn oil (control, AIN-93) or olive oil (6.25 g/L) throughout experiments. Animals were treated with CCl(4) for 4 weeks intraperitoneally. The mRNA expression of TGF-beta1 and collagen 1alpha2 (col1alpha2) in the liver was assessed by reverse transcriptase-polymerase chain reaction (RT-PCR). The HSCs were isolated from mice, and co-cultured with either oleic acid (100 microM) or linoleic acid (100 microM) for 2 days. The expression of alpha-smooth muscle actin (alpha-SMA) was assessed by immunohistochemistry. In addition, the production of hydroxyproline was determined. Serum alanine aminotransferase levels and the mRNA expression of TGF-beta and collalpha2 were significantly reduced by treatment of olive oil. Dietary olive oil blunted the expression of alpha-SMA in the liverand liver injury and hepatic fibrosis were prevented by treatment of olive oil. The number of alpha-SMA positive cells was significantly lower in HSCs co-cultured with oleic acid than in those co-cultured with linoleic acid. Concentration of hydroxyproline in culture medium was significantly lower in cells co-cultured with oleic acid than in the control. Dietary olive oil prevents CCl(4)-induced tissue injury and fibrosis in the liver. Since oleic acid inhibited activation of HSCs, oleic acid may play a key role on this mechanism.

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

AimTo 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.MethodologyForty-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.ResultsThe 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-β1 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.ConclusionThe 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.

A Continuous Observation of the Degenerative Process in the Intervertebral Disc of Smad3 Gene Knock-Out Mice

Pathologic changes were observed in the spine of small mother against decapentaplegic (Smad) 3 mice at different time points. To observe the degeneration of the intervertebral disc (IVD) in Smad3 gene knock-out mice with growth. Smad3 gene knock-out (Smad3) mice displays phenotypes similar to human osteoarthritis. Despite the similarities between IVD cartilage endplate and the articular cartilage, there has been relatively little interest in exploring the possibility that IVD degeneration might be driven by the deficiency of Smad3. The Smad3 mice were killed at the 10th, 30th, and 60th day after their birth and the IVD samples of spine were harvested for histologic and immunohistochemical studies. Total RNA isolated from these samples were used for real-time PCR analysis of type II collagen (Col2alpha1), type X collagen (Col10alpha1), aggrecan, and transforming growth factor-beta1 (TGF-beta1). Compared with the wild-type mice, Smad3 mice appeared significantly smaller in size. Radiograph showed that the spine of Smad3 mice is malformation and kyphosis. Histologic analysis revealed the declined height of cartilage endplate, decreased proteoglycan and collagen content in disc of Smad3 mice. With growth, especially of the 30- and 60-day old Smad3 mice, the protein positive staining of type II collagen, aggrecan, and TGF-beta1 in the disc decreased, while that of type X collagen increased. And the analysis of real-time PCR showed that the mRNA expression of Col2alpha1, aggrecan, and TGF-beta1 decreased, while that of Col10alpha1 increased. Smad3 gene knock-out mice develop IVD degeneration with growth.

Ciprofloxacin decreases survival in HT‐29 cells via the induction of TGF‐β1 secretion and enhances the anti‐proliferative effect of 5‐fluorouracil

Fluoroquinolones are potent anti-microbial agents with multiple effects on host cells and tissues. Previous studies have highlighted their pro-apoptotic effect on human cancer cells and an immunoregulatory role in animal models of inflammatory bowel disease. We examined the effect of ciprofloxacin on proliferation, cell cycle and apoptosis of HT-29 cells, a human colonic epithelial cell line sensitive to transforming growth factor (TGF)-beta1-mediated growth inhibition and its role in TGF-beta1 production. We also examined the effect of ciprofloxacin on proliferation of HT-29 cells in combination with 5-fluorouracil (5-FU), a well-established pro-apoptotic agent. Using subconfluent cultures of HT-29 and Caco-2 cells, we studied the effect of ciprofloxacin, TGF-beta1 and 5-FU on proliferation, apoptosis, necrosis and cell cycle. The effect of ciprofloxacin on TGF-beta1 mRNA expression and production was studied in RNA extracts and cell culture supernatants respectively, using confluent cultures. Ciprofloxacin decreased proliferation of HT-29 cells in a concentration- and time-dependent manner. This was mediated by accumulation of HT-29 cells into the S-phase but without any effect on apoptosis or necrosis. Additionally, ciprofloxacin enhanced the antiproliferative effect of 5-FU. Interestingly, ciprofloxacin was found to up-regulate TGF-beta1 production by HT-29 cells and its anti-proliferative effect was abolished when TGF-beta1 was blocked. Confirming this mechanism further, ciprofloxacin had no effect on Caco-2, a human colonic epithelial cell line that lacks functional TGF-beta1 receptors. We demonstrate a novel anti-proliferative and immunoregulatory effect of ciprofloxacin on human intestinal epithelial cells mediated via TGF-beta1.

Site‐specific anti‐tumor immunity: Differences in DC function, TGF‐β production and numbers of intratumoral Foxp3+ Treg

Gliomas localized within the CNS are generally not rejected by the immune system despite being immunogenic. This failure of the immune system has been associated both with glioma-derived immunosuppressive molecules and the immune-privileged state of the CNS. However, the relative contribution of tumor location to the glioma-mediated immunosuppression, as well as the immune mechanisms involved in the failure of glioma rejection are not fully defined. We report here that syngeneic GL261 gliomas growing either intracranially or subcutaneously in mice are infiltrated by DC and T cells. However, only subcutaneous gliomas elicit an effective anti-tumor immune response. In contrast to DC infiltrating subcutaneously grown GL261 gliomas, tumor-infiltrating DC from intracranial gliomas do not activate antigen-dependent T-cell proliferation in vitro. In addition, brain-localized GL261 gliomas are characterized by significantly higher numbers of Foxp3(+) Treg and higher levels of TGF-beta1 mRNA and protein expression when compared with GL261 gliomas in the skin. Our data show that gliomas in the CNS, but not in the skin, give rise to TGF-beta production and accumulation of both Treg and functionally impaired DC. Thus, not the tumor itself, but its location dictates the efficiency of the anti-tumor immune response.

Intrastromal Keratotomy with Femtosecond Laser Avoids Profibrotic TGF-β1 Induction

To examine expression of the profibrotic cytokine TGF-beta1 after selective intrastromal corneal injury with the use of a femtosecond laser. Rabbits underwent monocular intrastromal keratotomy at a preoperatively determined corneal depth of 160 to 200 mum with the use of a femtosecond laser. Femtosecond laser-induced TGF-beta1 expression was compared in nonoperated control eyes and eyes treated with photorefractive keratectomy (PRK). Follow-up examinations were performed 1, 3, 7, and 28 days after surgery. TGF-beta1 protein was identified by immunofluorescence labeling. With the use of laser-capture microdissection, epithelial, stromal, and endothelial cell layers were collected, and changes in TGF-beta1 mRNA expression were quantified with quantitative RT-PCR. TGF-beta1 mRNA and protein expression did not significantly increase after intrastromal femtosecond laser keratotomy. In contrast, TGF-beta1 was induced in corneal epithelial and stromal cells after PRK and showed up to 23-fold higher TGF-beta1 mRNA levels compared with control corneas. The increase of TGF-beta1 mRNA levels after PRK was accompanied by increased TGF-beta1 protein production. Isolated stromal injury with a femtosecond laser does not result in induction of the profibrotic cytokine TGF-beta1. Because TGF-beta1 has been implicated in a fibrotic response of the corneal stroma to injury, absence of TGF-beta1 induction argues for a favorable wound-healing response. These findings support highly selective intrastromal procedures in refractive surgery.