Changes in the balance between Treg and Th17 cells in patients with chronic hepatitis B

The purpose of this study was to explore the role of Treg cells, Th17 cells and cytokines associated with Treg/Th17 differentiation in the occurrence, development and outcome of chronic hepatitis B (CHB). To do so, we detected populations of Treg and Th17 cells and their associated cytokines in the peripheral blood of CHB patients. The populations of Treg cells (CD4(+)CD25(high)CD127(low) T cells) and Th17 cells (CD3(+)CD8(-)IL-17(+) T cells) were analyzed in 46 patients with low to moderate chronic hepatitis B (CHB-LM), 24 patients with severe chronic hepatitis B (CHB-S) and 20 healthy controls (HC) using flow cytometry. The levels of cytokines associated with Treg/Th17 differentiation, including IL-10, TGF-β1, IL-17 and IL-23, were measured by enzyme-linked immunosorbent assay (ELISA). Our study showed that the imbalance of Treg and Th17 cells might play an important role in the occurrence, development and outcome of CHB.

Inflammatory markers associated with osteoarthritis after destabilization surgery in young mice with and without Receptor for Advanced Glycation End-products (RAGE)

HtrA1, Ddr-2, and Mmp-13 are reliable biomarkers for osteoarthritis (OA), yet the exact mechanism for the upregulation of HtrA-1 is unknown. Some have shown that chondrocyte hypertrophy is associated with early indicators of inflammation including TGF-β and the Receptor for Advanced Glycation End-products (RAGE). To examine the correlation of inflammation with the expression of biomarkers in OA, we performed right knee destabilization surgery on 4-week-old-wild type and RAGE knock-out (KO) mice. We assayed for HtrA-1, TGF-β1, Mmp-13, and Ddr-2 in articular cartilage at 3, 7, 14, and 28 days post-surgery by immunohistochemistry on left and right knee joints. RAGE KO and wild type mice both showed staining for key OA biomarkers. However, RAGE KO mice were significantly protected against OA compared to controls. We observed a difference in the total number of chondrocytes and percentage of chondrocytes staining positive for OA biomarkers between RAGE KO and control mice. The percentage of cells staining for OA biomarkers correlated with severity of cartilage degradation. Our results indicate that the absence of RAGE did protect against the development of advanced OA. We conclude that HtrA-1 plays a role in lowering TGF-β1 expression in the process of making articular cartilage vulnerable to damage associated with OA progression.

Regional regulation of glutamate signaling during cuprizone-induced demyelination in the brain

Glutamate excitotoxicity is associated with a wide range of neurodegenerative disorders and also seems to be involved in the pathology of demyelinating disorders such as multiple sclerosis (MS). Cuprizone-induced toxic demyelination shows clear characteristics of MS such as demyelination and axonal damage without the involvement of the innate immune system. In this study, we have evaluated glutamate signaling during cuprizone-induced demyelination in the white and gray matter of mouse brain by studying the expression of ionotropic and metabotropic glutamate-receptors and -transporters by Affymetrix gene array analysis, followed by real-time PCR and western blot analysis. Cellular localization of glutamate transporters was investigated by fluorescence double-labeling experiments. Comparing white and gray matter areas, the expression of glutamate receptors was region-specific. Among NMDA receptor subunits, NR2A was up-regulated in the demyelinated corpus callosum (CC), whereas the metabotropic glutamate receptor mGluR2 was down-regulated in demyelinated gray matter. Glutamate-aspartate transporter (GLAST) co-localizing with GFAP(+) astrocytes was increased in both demyelinated CC and telencephalic cortex, whereas Slc1a4 transporter was up-regulated only in CC. Our data indicate that cuprizone treatment affects glutamate-receptors and -transporters differently in gray and white matter brain areas revealing particularly regulation of GLAST and Slc1a4 compared with other genes. This might have an important influence on brain-region selective sensitivity to neurotoxic compounds and the progression of demyelination as has been reported for MS and other demyelinating neurological diseases.

Inhibition of TGF-β1/Smad signal pathway is involved in the effect of Cordyceps sinensis against renal fibrosis in 5/6 nephrectomy rats

The present study aimed to investigate the effects of Cordyceps sinensis on renal fibrosis and its possible mechanisms. Sprague-Dawley rats were randomly divided into three groups: sham operation (SHAM) group, 5/6 subtotal nephrectomy (SNx) untreated group, and 5/6 subtotal nephrectomy treated with C. sinensis (2.0 g/kg d) (CS) group. Rats were studied 12 weeks after the surgery, and the CS group presented with significantly lower proteinuria, and better renal function compared with the SNx group (p<0.05). Pathological study showed that the glomerulosclerosis tubulointerstitial injury score was significantly reduced in the CS group compared with the SNx group. Furthermore, the mRNA expression of TGF-β1, Smad2 and Smad3 and the protein expression of TGF-β1, TβRI, TβRII and p-Smad2/3 were attenuated by the C. sinensis treatment. In constrast, the mRNA and protein expression of Smad7 was upregulated. Furthermore, the expression of α-SMA and FSP1 was also significantly attenuated, accompanied by the increasing expression of E-cadherin, suggesting the inhibition of the epithelial-mesenchymal transition (EMT).

IN CONCLUSION

C. sinensis exerted its antifibrotic effect on the SNx rats through the inhibition of the TGF-β1/Smad pathway.

PPARδ promotes oncogenic redirection of TGF-β1 signaling through the activation of the ABCA1-Cav1 pathway

TGF-β1 plays biphasic functions in prostate tumorigenesis, inhibiting cell growth at early stages but promoting malignant progression at later stages. However, the molecular basis for the oncogenic conversion of TGF-β1 function remains largely undefined. Here, we demonstrate that PPARδ is a direct transcription target of TGF-β1 and plays a critical role in oncogenic redirection of TGF-β1 signaling. Blockade of PPARδ induction enhances tumor cell response to TGF-β1-mediated growth inhibition, while its activation promotes TGF-β1-induced tumor growth, migration and invasion. PPARδ-mediated switch of TGF-β1 function is associated with down- and upregulation of Smad and ERK signaling, respectively, and tightly linked to its function to activate ABCA1 cholesterol transporter followed by caveolin-1 (Cav1) induction. Intriguingly, TGF-β1 activation of the PPARδ-ABCA1-Cav1 pathway facilitates degradation of TGF-β receptors (TβRs) and attenuates Smad but enhances ERK response to TGF-β1. Expression of PPARδ and Cav1 is tightly correlated in both prostate tissues and cell lines and significantly higher in cancer vs. normal tissues. Collectively, our study shows that PPARδ is a transcription target of TGF-β1 and contributes to the oncogenic conversion of TGF-β1 function through activation of the ABCA1-Cav1-TβR signaling axis.

Role of caveolin-1 in fibrotic diseases

Fibrosis underlies the pathogenesis of numerous diseases and leads to severe damage of vital body organs and, frequently, to death. Better understanding of the mechanisms resulting in fibrosis is essential for developing appropriate treatment solutions and is therefore of upmost importance. Recent evidence suggests a significant antifibrotic potential of an integral membrane protein, caveolin-1. While caveolin-1 has been widely studied for its role in the regulation of cell signaling and endocytosis, its possible implication in fibrosis remains largely unclear. In this review we survey involvement of caveolin-1 in various cellular processes and highlight different aspects of its antifibrotic activity. We hypothesize that caveolin-1 conveys a homeostatic function in the process of fibrosis by (a) regulating TGF-β1 and its downstream signaling; (b) regulating critical cellular processes involved in tissue repair, such as migration, adhesion and cellular response to mechanical stress; and (c) antagonizing profibrotic processes, such as proliferation. Finally, we consider this homeostatic function of caveolin-1 as a possible novel approach in treatment of fibroproliferative diseases.

Optimization of a chondrogenic medium through the use of factorial design of experiments

The standard culture system for in vitro cartilage research is based on cells in a three-dimensional micromass culture and a defined medium containing the chondrogenic key growth factor, transforming growth factor (TGF)-β1. The aim of this study was to optimize the medium for chondrocyte micromass culture. Human chondrocytes were cultured in different media formulations, designed with a factorial design of experiments (DoE) approach and based on the standard medium for redifferentiation. The significant factors for the redifferentiation of the chondrocytes were determined and optimized in a two-step process through the use of response surface methodology. TGF-β1, dexamethasone, and glucose were significant factors for differentiating the chondrocytes. Compared to the standard medium, TGF-β1 was increased 30%, dexamethasone reduced 50%, and glucose increased 22%. The potency of the optimized medium was validated in a comparative study against the standard medium. The optimized medium resulted in micromass cultures with increased expression of genes important for the articular chondrocyte phenotype and in cultures with increased glycosaminoglycan/DNA content. Optimizing the standard medium with the efficient DoE method, a new medium that gave better redifferentiation for articular chondrocytes was determined.

The right choice of antihypertensives protects primary human hepatocytes from ethanol- and recombinant human TGF-β1-induced cellular damage

Background

Patients with alcoholic liver disease (ALD) often suffer from high blood pressure and rely on antihypertensive treatment. Certain antihypertensives may influence progression of chronic liver disease. Therefore, the aim of this study is to investigate the impact of the commonly used antihypertensives amlodipine, captopril, furosemide, metoprolol, propranolol, and spironolactone on alcohol-induced damage toward human hepatocytes (hHeps).

Methods

hHeps were isolated by collagenase perfusion. Reactive oxygen species (ROS) were measured by fluorescence-based assays. Cellular damage was determined by lactate-dehydrogenase (LDH)-leakage. Expression analysis was performed by reverse-transcription polymerase chain reaction and Western blot. Transforming growth factor (TGF)-β signaling was investigated by a Smad3/4-responsive luciferase-reporter assay.

Results

Ethanol and TGF-β₁ rapidly increased ROS in hHeps, causing a release of 40%–60% of total LDH after 72 hours. All antihypertensives dose dependently reduced ethanol-mediated oxidative stress and cellular damage. Similar results were observed for TGF-β₁-dependent damage, except for furosemide, which had no effect. As a common mechanism, all antihypertensives increased heme-oxygenase-1 (HO-1) expression, and inhibition of HO-1 activity reversed the protective effect of the drugs. Interestingly, Smad3/4 signaling was reduced by all compounds except furosemide, which even enhanced this profibrotic signaling. This effect was mediated by expressional changes of Smad3 and/or Smad4.

Conclusions

Our results suggest that antihypertensives may both positively and negatively influence chronic liver disease progression. Therefore, we propose that in future patients with ALD and high blood pressure, they could benefit from an adjusted antihypertensive therapy with additional antifibrotic effects.

NO-releasing xanthine KMUP-1 bonded by simvastatin attenuates bleomycin-induced lung inflammation and delayed fibrosis

BACKGROUND AND PURPOSE

Pulmonary fibrosis (PF) is a progressing lung injury initiated by pulmonary inflammation (PI). Bleomycin (BLM) is the most common pathogenesis of PF through early PI and extensive extracellular matrix deposition. This study is aimed to determine whether NO-releasing KMUP-1 inhibits PI and PF, and if so, the benefits of KMUP-1S resulted from simvastatin (SIM)-bonding to KMUP-1.

EXPERIMENT APPROACH

C57BL/6 male mice were intra-tracheally administered BLM (4 U/kg) at day 0. KMUP-1 (1-5 mg/kg), KMUP-1S (2.5 mg/kg), SIM (5 mg/kg), Plus (KMUP-1 2.5 mg/kg + SIM 2.5 mg/kg), and clarithromycin (CAM, 10 mg/kg) were orally and daily administered for 7 and 28 days, respectively, to mice, sacrificed at day-7 and day-28 to isolate the lung tissues, for examining the inflammatory and fibrotic signaling and measuring the cell population and MMP-2/MMP-9 activity in broncholaveolar lavage fluid (BAL).

KEY RESULTS

KMUP-1 and KUP-1S significantly decreased neutrophil counts in BAL fluid. Fibroblastic foci were histologically assessed by H&E and Masson's trichrome stain and treated with KMUP-1 and references. Lung tissues were determined the contents of collagen and the expressions of TGF-β, α-SMA, HMGB1, CTGF, eNOS, p-eNOS, RhoA, Smad3, p-Smad3, MMP-2 and MMP-9 by Western blotting analyses, respectively. These changes areregulated by NO/cGMP and inhibited by various treatments. KMUP-1 and KMUP-1S predominantly prevented HMGB1/MMP-2 expression at day-7 and reduced TGF-β/phosphorylated Smad3 and CTGF at day-28.

CONCLUSIONS AND IMPLICATIONS

KMUP-1 and KMUP-S restore eNOS, inhibit iNOS/ROCKII/MMP-2/MMP-9, attenuate histologic collagen disposition and reduce BALF inflammatory cells, potentially useful for the treatment of BLM-lung PF.

Epigallocatechin-3-gallate inhibits collagen production of nasal polyp-derived fibroblasts

Nasal polyps are chronic inflammatory conditions characterized by myofibroblast differentiation and extracelluar matrix accumulation. The major catechin from green tea is (-)-epigallocatechin-3-gallate (EGCG), which has garnered attention for its potential to prevent oxidative stress-related diseases. The purpose of this study was twofold: (i) to determine the effect of EGCG on fibroblast differentiation into myofibroblasts and extracellular matrix accumulation in transforming growth factor (TGF)-β1-induced nasal polyp-derived fibroblasts (NPDFs) and (ii) to determine if the antioxidative effect of EGCG on reactive oxygen species (ROS) production in TGF-β1-induced NPDFs is involved in the aforementioned processes. TGF-β1-induced NPDFs were treated with or without EGCG. α-smooth muscle actin (α-SMA) and collagen type I mRNA were analyzed by reverse transcription-polymerase chain reaction. α-SMA protein was also detected using immunofluorescent staining. The amount of total soluble collagen was analyzed by Sircol collagen assay. ROS activity was measured by the nitroblue tetrazolium reduction assay and visualized by fluorescent microscopy. EGCG significantly inhibited expressions of α-SMA and collagen type I mRNA and reduced α-SMA and collagen protein levels at concentrations of 10-20 µg/mL. EGCG also inhibited TGF-β1-induced ROS production at the same concentrations. These results suggest the possibility that EGCG may be effective at inhibiting the development of nasal polyps through an anti-oxidant effect.

Overexpression of Sulf2 in idiopathic pulmonary fibrosis

Previously, we have shown that heparan sulfate (HS) 6-O-endosulfatase 1 (Sulf1) is a transforming growth factor-β1 (TGF-β1)-responsive gene in normal human lung fibroblasts and functions as a negative feedback regulator of TGF-β1 and that TGF-β1 induces the expression of Sulf1 as well as that of the closely related Sulf2 in a murine model of pulmonary fibrosis. In this study, we focused on the role of Sulf2 in modulating TGF-β1 function and the development of pulmonary fibrosis. We found that Sulf2 mRNA was overexpressed in lung samples from human patients with idiopathic pulmonary fibrosis (IPF), and Sulf2 protein was specifically localized to the hyperplastic type II alveolar epithelial cells (AECs). In vitro, TGF-β1 induced the expression of Sulf2 with accompanied HS 6-O-desulfation in A549 cells, adenocarcinoma cells derived from the type II alveolar epithelium. Using small interference RNA to block Sulf2 expression, we observed a biphasic TGF-β1 response with early enhanced Smad activation, but eventually reduced TGF-β1 target gene expression in Sulf2 knockdown A549 cells compared with the control cells. To study the role of Sulf2 in normal type II AECs, we isolated primary type II cells from wild-type and Sulf2 knockout mice. We observed enhanced Smad activation as well as enhanced TGF-β1 target gene expression in Sulf2 knockout type II AECs compared with wild-type type II AECs. In conclusion, Sulf2 is overexpressed in IPF and may play a role in regulating TGF-β1 signaling in type II AECs.

Microenvironment and tumor cell plasticity: an easy way out

Cancer cells undergo genetic changes allowing their adaptation to environmental changes, thereby obtaining an advantage during the long metastatic route, disseminated of several changes in the surrounding environment. In particular, plasticity in cell motility, mainly due to epigenetic regulation of cancer cells by environmental insults, engage adaptive strategies aimed essentially to survive in hostile milieu, thereby escaping adverse sites. This review is focused on tumor microenvironment as a collection of structural and cellular elements promoting plasticity and adaptive programs. We analyze the role of extracellular matrix stiffness, hypoxia, nutrient deprivation, acidity, as well as different cell populations of tumor microenvironment.

FGFR4 and TGF-β1 expression in hepatocellular carcinoma: correlation with clinicopathological features and prognosis

OBJECTIVE

To investigate the expression and correlation of transforming growth factor-β1 (TGF-β1) and fibroblast growth factor receptor 4 (FGFR4) in human hepatocellular carcinoma (HCC) and the relationship with clinicopathological features and prognosis.

MATERIALS AND METHODS

The expression of TGF-β1 and FGFR4 in 126 HCC samples was detected immunohistochemically. Combined with clinical postoperative follow-up data, the expression of TGF-β1 and FGFR4 in HCC and the relationship with the prognosis of patients were analyzed by statistically.

RESULTS

The positive expression rate of TGF-β1 was 84.1% (106/126) in tumors, and that in peritumoral liver tissues was 64.3% (81/126); the positive expression rate of FGFR4 in tumors was 74.6% (94/126) and that in peritumoral liver tissues was 57.1% (72/126). The expression of TGF-β1 and FGFR4 in the carcinoma tissues was significantly higher than that in peritumoral liver tissues (p < 0.05). Intratumoral TGF-β1 and FGFR4 expression was associated with TNM stage (p < 0.05). TGF-β1 and FGFR4 expression levels didn't significantly correlate with other clinicopathological parameters, including age, sex, tumor size, serum AFP level, tumor differentiation, lymph node metastasis, etc. (p > 0.05). TGF-β1 expression was positively correlated with FGFR4 expression (r = 0.595, p < 0.05). Patients with positive FGFR4 or TGF-β1 expression had shorter overall survival compared with negative expression (p < 0.05).

CONCLUSIONS

The expression of TGF-β1 and FGFR4 could make synergy on the occurrence and progression of HCC, and may be used as prognosis indicators for HCC patients.

The role of fibrosis in Duchenne muscular dystrophy

Muscular dystrophies such as Duchenne muscular dystrophy (DMD) are usually approached as dysfunctions of the affected skeletal myofibres and their force transmission. Comparatively little attention has been given to the increase in connective tissue (fibrosis) which accompanies these muscular changes. Interestingly, an increase in endomysial tissue is apparent long before any muscular degeneration can be observed. Fibrosis is the result of a reactive or reparative process involving mechanical, humoral and cellular factors. Originating from vulnerable myofibres, muscle cell necrosis and inflammatory processes are present in DMD. Muscular recovery is limited due to the limited number and capacity of satellite cells. Hence, a proactive and multimodal approach is necessary in order to activate protective mechanisms and to hinder catabolic and tissue degrading pathways. Several avenues are discussed in terms of potential antifibrotic therapy approaches. These include pharmaceutical, nutritional, exercise-based and other mechanostimulatory modalities (such as massage or yoga-like stretching) with the intention of exerting an anti-inflammatory and antifibrotic effect on the affected muscular tissues. A preventive intervention at an early age is crucial, based on the early and seemingly non-reversible nature of the fibrotic tissue changes. Since consistent assessment is essential, different measurement technologies are discussed.

TGF-β1 expression in wound healing is acutely affected by experimental malnutrition and early enteral feeding

Malnutrition is associated with the delay or failure of healing. We assessed the effect of experimental malnutrition and early enteral feeding with standard diet or diet supplemented with arginine and antioxidants on the levels of mRNA encoding growth factors in acute, open wound healing. Standardised cutaneous dorsal wounds and gastrostomies for enteral feeding were created in malnourished (M, n = 27) and eutrophic control (E, n = 30) Lewis male adult rats. Both M and E rats received isocaloric and isonitrogenous regimens with oral chow and saline (C), standard (S) or supplemented (A) enteral diets. On post-trauma day 7, mRNA levels of growth factor genes were analysed in wound granulation tissue by reverse transcription polymerase chain reaction (RT-PCR). M(C) rats had significantly lower transforming growth factor β(TGF-β1 ) mRNA levels than E(C) rats (2·58 ± 0·83 versus 3·53 ± 0·57, P < 0·01) and in comparison with M(S) and M(A) rats (4·66 ± 2·49 and 4·61 ± 2·11, respectively; P < 0·05). VEGF and KGF-7 mRNA levels were lower in M(A) rats than in E(A) rats (0·74 ± 0·16 versus 1·25 ± 0·66; and 1·07 ± 0·45 versus 1·79 ± 0·89, respectively; P≤ 0·04), but did not differ from levels in E(C) and M(C) animals. In experimental open acute wound healing, previous malnutrition decreased local mRNA levels of TGF-β1 genes, which was minimised by early enteral feeding with standard or supplemented diets.

Selective phosphodiesterase-5 (PDE-5) inhibitor vardenafil ameliorates renal damage in type 1 diabetic rats by restoring cyclic 3',5' guanosine monophosphate (cGMP) level in podocytes

BACKGROUND

Diabetic nephropathy (DN) is characterized by podocyte damage and increased phosphodiesterase-5 (PDE-5) activity-exacerbating nitric oxide (NO)-cyclic 3',5' guanosine monophosphate (cGMP) pathway dysfunction. It has been shown that PDE-5 inhibition ameliorates DN. The role of podocytes in this mechanism remains unclear. We investigated how selective PDE-5 inhibition influences podocyte damage in streptozotocin (STZ) diabetic rats.

METHODS

Male Sprague-Dawley rats (250-300 g) were injected with STZ and divided into two groups: (i) STZ control (non-treated, STZ, n=6) and (ii) STZ+vardenafil treatment (10 mg/kg/day, STZ-Vard, n=8). Non-diabetic rats served as negative controls (Control, n=7). Following 8 weeks of treatment, immunohistochemical and molecular analysis of the kidneys were performed.

RESULTS

Diabetic rats had proteinuria, increased renal transforming growth factor (TGF)-β1 expression and podocyte damage when compared with controls. Vardenafil treatment resulted in preserved podocyte cGMP levels, less proteinuria, reduced renal TGF-β1 expression, desmin immunostaining in podocytes and restored both nephrin and podocin mRNA expression. Diabetes led to increased glomerular nitrotyrosine formation and renal neuronal nitric oxide synthase and endothelial nitric oxide synthase mRNA expression, but vardenafil did not influence these parameters.

CONCLUSIONS

Our data suggest that a dysfunctional NO-cGMP pathway exacerbates podocyte damage in diabetes. In conclusion, vardenafil treatment preserves podocyte function and reduces glomerular damage, which indicates therapeutic potential in patients with DN.

Involvement of mast cell chymase in burn wound healing in hamsters

Mast cells play a significant role in the late stage of wound healing following burn injuries. In the present study, the possible role of mast cell chymase in burn wound healing was examined using a mast cell membrane stabilizer, ketotifen, in hamsters. A total of 28 hamsters were randomly divided into two groups (n=14), termed as the control and ketotifen groups. A deep partial-thickness burn injury was made on the back skin of the hamsters. The control group was orally administered physiological saline (1 ml) and the ketotifen group was orally administered ketotifen (4 mg/kg) once daily, two days prior to and two days subsequent to the burn. The results showed that concentrations of angiotensin II (Ang II), TGF-β1, collagens I and III and interleukin (IL)-1β were significantly decreased in the ketotifen group compared with those in the control group. However, there was no significant difference in fibroblast apoptosis between the two groups. The release of mast cell chymase was inhibited by the mast cell membrane stabilizer ketotifen. Taken together, these results suggest that mast cell chymase may participate in the process of burn wound healing. Chymase may therefore be a promising therapeutic target for the treatment of burn wounds.

T Cell Immunoglobulin Mucin Domain (TIM)-3 Promoter Activity in a Human Mast Cell Line

T cell immunoglobulin mucin domain (TIM)-3 is an immunomodulatory molecule and upregulated in T cells by several cytokines. TIM-3 also influences mast cell function but its transcriptional regulation in mast cells has not been clarified. Therefore, we examined the transcript level and the promoter activity of TIM-3 in mast cells. The TIM-3 transcript level was assessed by real-time RT-PCR and promoter activity by luciferase reporter assay. TIM-3 mRNA levels were increased in HMC-1, a human mast cell line by TGF-β1 stimulation but not by stimulation with interferon (IFN)-α, IFN-λ, TNF-α, or IL-10. TIM-3 promoter -349~+144 bp region relative to the transcription start site was crucial for the basal and TGF-β1-induced TIM-3 promoter activities in HMC-1 cells. TIM-3 promoter activity was increased by overexpression of Smad2 and Smad4, downstream molecules of TGF-β1 signaling. Our results localize TIM-3 promoter activity to the region spanning -349 to +144 bp in resting and TGF-β1 stimulated mast cells.

Differential effects of domoic acid and E. coli lipopolysaccharide on tumor necrosis factor-alpha, transforming growth factor-beta1 and matrix metalloproteinase-9 release by rat neonatal microglia: evaluation of the direct activation hypothesis

The excitatory amino acid domoic acid is the causative agent of amnesic shellfish poisoning in humans. The in vitro effects of domoic acid on rat neonatal brain microglia were compared with E. coli lipopolysaccharide (LPS), a known activator of microglia mediator release over a 4 to 24 hour observation period. LPS [3 ng/mL] but not domoic acid [1mM] stimulated a statistically significant increase in TNF-α mRNA and protein generation. Furthermore, both LPS and domoic acid did not significantly affect TGF-β1 gene expression and protein release. Finally, an in vitro exposure of microglia to LPS resulted in statistically significant MMP-9 expression and release, thus extending and confirming our previous observations. However, in contrast, no statistically significant increase in MMP-9 expression and release was observed after domoic acid treatment. Taken together our observations do not support the hypothesis that a short term (4 to 24 hours) in vitro exposure to domoic acid, at a concentration toxic to neuronal cells, activates rat neonatal microglia and the concomitant release of the pro-inflammatory mediators tumor necrosis factor-α (TNF-α) and matrix metalloproteinases-9 (MMP-9), as well as the anti-inflammatory cytokine transforming growth factor β1 (TGF-β1).

Synergistic Effect of TGF-β1 And BMP-7 on Chondrogenesis and Extracellular Matrix Synthesis: An In Vitro Study

Introduction:

The purpose of the present study seeks to determine the signal timing of BMP–7 and TGF-β1 from a novel chitosan based hydrogel system that may affect chondrocyte proliferation resulting in the presence of a synergism seen conspicuously in consecutive controlled delivery.

Methods:

Four groups of cultured chondrocytes were seeded on a novel designed chitosan based hydrogel. The hydrogel was left empty (control) in one group and loaded with BMP–7, TGF-β1 and their combination in the other groups, respectively. Hydrogel structure was analyzed with scanning electron microscope. The release kinetics of Growth Factors (GFs) was determined with ELISA. Chondrocyte viability and toxicity after being tested with MTS and collagen type II synthesis, were quantified with western blotting. Canonical regression analysis was used for measuring statistical evaluation.

Results:

Chitosan based hydrogel allowed controlled release of GFs in different time intervals for BMP–7 and TGF-β1. Double peak concentration gradient was found to be present in the group loaded with both GFs. In this group, substantially higher chondrocyte growth and collagen synthesis were also detected.

Conclusions:

We concluded that, chitosan based hydrogel systems may be adjusted to release GFs consecutively during biodegradation at the layers of surface, which may increase the cell number and enhance collagen type II synthesis.

Effects of TGF-β1 and VEGF-A transgenes on the osteogenic potential of bone marrow stromal cells in vitro and in vivo

An exogenous supply of growth factors and bioreplaceable scaffolds may help bone regeneration. The aim of this study was to examine the effects of TGF-β1 and VEGF-A transgenes on the osteogenic potential of bone marrow stromal cells. Rat bone marrow stromal cells were transfected with plasmids encoding mouse TGF-β1 and/or VEGF-A complementary DNAs and cultured for up to 28 days. Furthermore, collagen scaffolds carrying combinations of the plasmids-transfected cells were implanted subcutaneously in rats. The transgenes increased alkaline phosphatase activity, enhanced mineralized nodule formation, and elevated osteogenic gene expressions in vitro. In vivo, messenger RNA expression of osteogenic genes such as BMPs and Runx2 elevated higher by the transgenes. The data indicate that exogenous TGF-β1 and VEGF-A acted synergistically and could induce osteoblastic differentiation of bone marrow stromal cells in both cell culture and an animal model. The results may provide valuable information to optimize protocols for transgene-and-cell-based tissue engineering.

Lipid Peroxidation and Transforming Growth Factor-β1 Levels in Gastric Cancer at Pathologic Stages

OBJECTIVE

High levels of TGF-β1 and enhanced TGF-β1 receptor signaling are related to the pathology of gastric cancer. This effect is caused by oxidative stress and lipid peroxidation products. The aim of this study was to investigate the levels of TGF-β1 and lipid peroxidation products in gastric cancer patients and their correlation with pathologic stage.

MATERIAL AND METHODS

Lipid peroxidation products and TGF-β1 levels were studied in the serum samples of 50 gastric cancer patients and 18 control subjects.

RESULTS

HNE-protein adducts and TGF-β1 levels were significantly higher in T2, T3 and T4 gastric cancers than in either the T1 stage or controls (p<0.001). Pathologic stage was correlated with TGF-β1 levels (r=0.702, p<0.05).

CONCLUSION

These markers production may contribute to tumor angiogenesis and aid in the prognosis of the gastric cancer.

Less expression of prohibitin is associated with increased paired box 2 (PAX2) in renal interstitial fibrosis rats

Prohibitin (PHB) and paired box 2 (PAX2) are associated with the development of renal interstitial fibrosis (RIF). This study was performed to investigate whether or not the PHB could regulate the PAX2 gene expression in unilateral ureteral obstruction (UUO) in rats. Eighty Wistar male rats were randomly divided into two groups: sham operation group (SHO) and model group subjected to unilateral ureteral obstruction (GU), n = 40, respectively. The model was established by left ureteral ligation. Renal tissues were collected at 14-day and 28-day after surgery. RIF index, protein expression of PHB, PAX2, transforming growth factor-βl (TGF-β1), α-smooth muscle actin (α-SMA), collagen-IV (Col-IV), fibronectin (FN) or cleaved Caspase-3, and cell apoptosis index in renal interstitium, and mRNA expressions of PHB, PAX2 and TGF-β1 in renal tissue were detected. When compared with those in SHO group, expression of PHB (mRNA and protein) was significantly reduced, and expressions of PAX2 and TGF-β1 (protein and mRNA) were markedly increased in the GU group (each p < 0.01). Protein expressions of α-SMA, Col-IV, FN and cleaved Caspase-3, and RIF index or cell apoptosis index in the GU group were markedly increased when compared with those in the SHO group (each p < 0.01). The protein expression of PHB was negatively correlated with protein expression of PAX2, TGF-β1, α-SMA, Col-IV, FN or cleaved Caspase-3, and RIF index or cell apoptosis index (all p < 0.01). In conclusion, less expression of PHB is associated with increased PAX2 gene expression and RIF index in UUO rats, suggesting that increasing the PHB expression is a potential therapeutic target for prevention of RIF.

Telmisartan counteracts TGF-β1 induced epithelial-to-mesenchymal transition via PPAR-γ in human proximal tubule epithelial cells

Chronic renal failure (CRF) mainly results from kidney fibrosis. Epithelial-to-mesenchymal transition (EMT) occurs in stressed tubular epithelial cells and contributes to renal fibrosis. Transforming growth factor-β1 (TGF-β1) has been shown to initiate and complete the whole EMT process. Peroxisome proliferators-activated receptor-γ (PPAR-γ) exerts anti-inflammatory, anti-fibrotic and vaculo-protective effects on different renal diseases. Telmisartan is a member of angiotensin II (Ang II) receptor blocker (ARB) family. Recent studies show that Telmisartan has a partial agonistic effect on PPAR-γ. Therefore, we tested the hypothesis that Telmisartan reverses the progression of induced EMT by TGF-β1 in cultured human renal proximal tubular epithelial (HK-2) cells. Cultured HK-2 cells were treated with TGF-β1 (3 ng/ml), a combination of TGF-β1 and Telmisartan (10-200 umol/L) and a combination of TGF-β1, Telmisartan and GW9662, a PPAR-γ antagonist for 48 hours. EMT was determined by quantitative real-time PCR analysis of E-cadherin (E-cad), Connective Tissue Growth Factor (CTGF) and PPAR-γ transcript expression and immunocytochemical analysis of E-cad, α-Smooth Muscle Actin (α-SMA) and PPAR-γ protein expression. TGF-β1 induced phenotypic EMT in cultured HK-2 cell line via significantly reduced E-cad expression and significantly increased CTGF, α-SMA expression in association with the loss of epithelial morphology. Telmisartan reversed all EMT markers in a dose-dependent manner which was inhibited by PPAR antagonist GW9662. In the present study, it was suggested that Telmisartan attenuated TGF-β1 induced EMT by agonistic activation of PPAR-γ.

Lactoferrin Stimulates Mouse Macrophage to Express BAFF via Smad3 Pathway

B cell-activating factor belonging to the TNF family (BAFF) is primarily expressed by macrophages and stimulates B cell proliferation, differentiation, survival, and Ig production. In this study, we explored the effect of lactoferrin (LF) on BAFF expression by murine macrophages. We determined the level of BAFF expression at the transcriptional and protein levels using RT-PCR and ELISA, respectively. LF markedly enhanced BAFF expression in mouse macrophages at both the transcriptional and protein levels. Overexpression of Smad3/4 further increased LF-induced BAFF transcription while DN-Smad3 abolished the LF-induced BAFF expression. These results demonstrate that LF can enhance BAFF expression through Smad3/4 pathway.

Regulation of TGF-β1-Induced Pro-Apoptotic Signaling by Growth Factor Receptors and Extracellular Matrix Receptor Integrins in the Liver

Hepatocellular carcinoma (HCC) often arises from chronically diseased livers. Persistent liver inflammation causes the accumulation of excessive extracellular matrix (ECM) proteins and impairs the liver function, finally leading to the development of HCC. A pleiotropic cytokine, transforming growth factor (TGF)-β1, plays critical roles throughout the process of fibrogenesis and hepatocarcinogenesis. In the liver, TGF-β1 inhibits the proliferation of hepatocytes and stimulates the production of ECM from hepatic stellate cells (HSCs) to maintain tissue homeostasis. During disease progression, both growth factors/cytokines and the ECM alter the TGF-β1 signals by modifying the phosphorylation of Smad proteins at their C-terminal and linker regions. TGF-β1 stimulates the expression of integrins, cellular receptors for ECM, along with an increase in ECM accumulation. The activation of integrins by the ECM modulates the response to TGF-β1 in hepatic cells, resulting in their resistance to TGF-β1-induced growth suppression in hepatocytes and the sustained production of ECM proteins in activated HSCs/myofibroblasts. Both growth factor receptors and integrins modify the expression and/or functions of the downstream effectors of TGF-β1, resulting in the escape of hepatocytes from TGF-β1-induced apoptosis. Recent studies have revealed that the alterations of Smad phosphorylation that occur as the results of the crosstalk between TGF-β1, growth factors and integrins could change the nature of TGF-β1 signals from tumor suppression to promotion. Therefore, the modification of Smad phosphorylation could be an attractive target for the prevention and/or treatment of HCC.

TGF-β(1) in retinal ganglion cells in rats with chronic ocular hypertension: its expression and anti-apoptotic effect

AIM

To investigate the anti-apoptotic effect of transforming growth factor beta-1 (TGF-β(1)) on chronic ocular hypertension.

METHODS

The expression of TGF-β(1) in retinal ganglion cells (RCGs) was measured using the immunohistochemiscal S-P method and real-time PCR in the normally control group, the ocular hypertension group (experimental group A), the ocular hypertension plus antibody intervention group (experimental group B) and the ocular hypertension plus antigen intervention group (experimental group C) at 1, 2, 3 and 4 weeks postoperatively. The count of apoptotic RCGs was measured using the TUNEL method.

RESULTS

The expression of TGF-β(1 )was significantly higher in experimental group C than that in other three groups (P<0.05). The expression was the lowest in experimental group B (4.17%). A statistically significant difference was noted between the four groups (P<0.01). The count of apoptotic RCGs was statistically significantly lower in experimental group C than that in the experimental groups A and B (P<0.01). A statistically significant difference was noted in the count of apoptotic RCGs between these three experimental groups (P<0.01).

CONCLUSION

TGF-β(1) can inhibit the apoptosis of RCGs in rats with chronic ocular hypertension.

Role of chymase in the pathogenesis of experimental liver fibrosis in rats

AIM: To investigate the role of chymase in the pathogenesis of dimethylnitrosamine (DMN)-induced liver fibrosis in rats.

METHODS: Thirty male Wistar rats were randomly divided into three groups. The model group was administered with 10% DMN. The interventional group was given soybean trypsin inhibitor (SBTI) after induction of liver fibrosis with DMN. The normal group was given normal sodium. Liver histological and ultramicroscopic changes were observed, and serum indices for liver fibrosis, serum transforming growth factor β1 (TGF-β1) and hepatic chymase-like activity were measured at the end of the experiment.

RESULTS: Compared to the model group, the interventional group had narrower fiber separation and showed no typical pseudo-lobule. Transmission electron microscopy demonstrated that hepatic cell damage in the interventional group was lessened significantly as compared to that in the model group, and only scattered collagen fiber was observed in the sinus hepaticus. Serum levels of HA, LN, PC III, C IV, TGF-β1 and hepatic chymase-like activity in the interventional group were significantly lower than those in the model group (all P < 0.05).

CONCLUSION: Chymase participates in the development of liver fibrosis possibly by direct or indirect induction of TGF-β1 and may be a promising therapy target for hepatic fibrosis.

The Expressions of TGF-β(1) and IL-10 in Cultured Fibroblasts after ALA-IPL Photodynamic Treatment

BACKGROUND

Topical photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) was originally used for treating superficial skin tumors. The application of PDT to other inflammatory dermatoses like acne vulgaris, psoriasis, granuloma annulare, localized scleroderma and lichen sclerosus has recently been introduced. However, the underlying mechanisms are not well understood. We've previously reported the induction of tumor growth factor (TGF)-β(1) and interleukin (IL)-10 after PDT with ALA and intense pulsed light (IPL) in cultured HaCaT cells.

OBJECTIVE

The purpose of this study was to investigate the expressions of TGF-β(1) and IL-10 in cultured fibroblasts after PDT with using ALA and IPL.

METHODS

Cultured fibroblasts were treated with ALA-IPL PDT (1µmol/L of ALA; 0, 4, 8 and 12 J/cm(2) of IPL). The expressions of TGF-β(1) and IL-10 were investigated by reverse transcription-polymerase chain reaction and enzyme linked immunosorbent assay.

RESULTS

TGF-β(1) mRNA and protein were reduced down to 0.52- and 0.63-fold, respectively, after PDT and the IL-10 protein was increased up to 2.74-fold after PDT.

CONCLUSION

The reduction of TGF-β(1) was prominent after PDT and so an antisclerotic effect can be expected after PDT. The induction of IL-10 may contribute to the anti-inflammatory effect, which explains the therapeutic benefit of PDT for inflammatory dermatoses.

Transforming Growth Factor-β1 Antagonizes Interleukin-5 Pro-Survival Signaling by Activating Calpain-1 in Primary Human Eosinophils

BACKGROUND

Eosinophils rapidly undergo apoptosis unless exposed to prosurvival cytokines such as interleukin 5 (IL-5) or granulocyte-macrophage colony stimulating factor (GM-CSF). In vivo, eosinophils are exposed to TGF-β 1 which can induce apoptosis suggesting it may function to counteract the effects of IL-5 or GM-CSF and limit, in vivo tissue eosinophilia.

OBJECTIVE

The objective of this study was to investigate the proapoptotic effects of TGF-β alone and in combination with IL-5 on eosinophils.

METHODS

Peripheral blood eosinophil (PBEos) viability was assessed using flow cytometry after exposure to TGF-β1 and IL-5. Calpain-1 activation was determined in cell extracts by western blot analysis of endogenous substrates and with a fluorogenic α-spectrin substrate. Molecular interactions between calpain1 and calpastatin were assessed by immunoprecipitation and western blotting.

RESULTS

Physiologic concentrations of TGF-β1 significantly antagonized the prosurvival effects of IL-5. TGF-β1-induced apoptosis was suppressed by inhibitors of calpain, or its downstream target, caspase 3. TGF-β1 signaling through Smad3 was unaffected by IL-5 and was required for the pro-apoptotic effects of TGF-β1. However, IL-5 induced Akt phosphorylation was inhibited by TGF-β1 and was associated with accelerated calpain cleavage and eosinophil death.

CONCLUSION

TGF-β1 induces calpain-1 activation through antagonism of Akt which induces caspase activation and eosinophil apoptosis.

Tiul1 and TGIF are Involved in Downregulation of TGFbeta1-induced IgA Isotype Expression

TGF-β1 is well known to induce Ig germ-line α (GLα) transcription and subsequent IgA isotype class switching recombination (CSR). Homeodomain protein TG-interacting factor (TGIF) and E3-ubiquitin ligases TGIF interacting ubiquitin ligase 1 (Tiul1) are implicated in the negative regulation of TGF-β signaling. In the present study, we investigated the roles of Tiul1 and TGIF in TGFβ1-induced IgA CSR. We found that over-expression of Tiul1 decreased TGFβ1-induced GLα promoter activity and strengthened the inhibitory effect of Smad7 on the promoter activity. Likewise, overexpression of TGIF also diminished GLα promoter activity and further strengthened the inhibitory effect of Tiul1, suggesting that Tiul1 and TGIF can down-regulate TGFβ1-induced GLα expression. In parallel, overexpression of Tiul1 decreased the expression of endogenous IgA CSR-predicitive transcripts (GLT_α, PST_α, and CT_α) and TGFβ1-induced IgA secretion, but not GLT_γ3 and IgG3 secretion. Here, over-expressed TGIF further strengthened the inhibitory effect of Tiul1. These results suggest that Tiul1 and TGIF act as negatively regulators in TGFβ1-induced IgA isotype expression.

The Effects of TWEAK, Fn14, and TGF-beta1 on Degeneration of Human Intervertebral Disc

OBJECTIVE

The purpose of this study is to explain the effect and reciprocal action among tumor necrosis factor (TNF) like weak inducer of apoptosis (TWEAK), fibroblast growth factor-inducible 14 (Fn14), and transforming growth factor-beta1 (TGF-beta1) on degeneration of human intervertebral disc (IVD).

METHODS

Human intervertebral disc tissues and cells were cultured with Dulbecco's Modified Eagle's Medium/Nutrient F-12 Ham (DMEM/F-12) media in 37, 5% CO(2) incubator. When IVD tissues were cultured with TWEAK, Fn14 that is an antagonistic receptor for TWEAK and TGF-beta1, the level of sulfated glycosaminoglycan (sGAG) was estimated by dimethyl methyleneblue (DMMB) assay and sex determining region Y (SRY)-box 9 (Sox9) and versican messenger ribonucleic acid (mRNA) levels were estimated by reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTS

When human IVD tissue was cultured for nine days, the sGAG content was elevated in proportion to culture duration. The sGAG was decreased significantly by TWEAK 100 ng/mL, however, Fn14 500 ng/mL did not change the sGAG production of IVD tissue. The Fn14 increased versican and Sox9 mRNA levels decreased with TWEAK in IVD tissue TGF-beta1 20 ng/mL elevated the sGAG concentration 40% more than control. The sGAG amount decreased with TWEAK was increased with Fn14 or TGF-beta1 but the result was insignificant statistically. TGF-beta1 increased the Sox9 mRNA expression to 180% compared to control group in IVD tissue. Sox9 and versican mRNA levels decreased by TWEAK were increased with TGF-beta1 in primary cultured IVD cells, however, Fn14 did not show increasing effect on Sox9 and versican.

CONCLUSION

This study suggests that TWEAK would act a role in intervertebral disc degeneration through decreasing sGAG and the mRNA level of versican and Sox9.

Single nucleotide polymorphisms of cytokine genes are associated with fibrosis of the intrahepatic bile duct wall in human clonorchiasis

This study examined the association of cytokine gene polymorphisms with intrahepatic bile duct wall fibrosis in human clonorchiasis. A total of 240 residents in Heilongjiang, China underwent ultrasonography, blood sampling, and stool examination. Single nucleotide polymorphism (SNP) sites for IFN-gamma (+874 T/A), IL-10 (-1,082 G/A, -819 C/T, -592 C/A), TNF-alpha (-308 G/A), and TGF-beta1 (codon 10 T/C, codon 25 G/C) genes were observed with the TaqMan allelic discrimination assay. No significant correlation was observed between individual cytokine gene polymorphisms and intrahepatic duct dilatation (IHDD). Among individuals with clonorchiasis of moderate intensity, the incidence of IHDD was high in those with IFN-gamma intermediate-producing genotype, +874AT (80.0%, P = 0.177), and in those with TNF-alpha low-producing genotype, -308GG (63.0%, P = 0.148). According to the combination of IFN-gamma and TNF-alpha genotypes, the risks for IHDD could be stratified into high (intermediate-producing IFN-gamma and low producing TNF-alpha), moderate, and low (low-producing IFN-gamma and high producing TNF-alpha) risk groups. The incidence of IHDD was significantly different among these groups (P = 0.022): 88.9% (odds ratio, OR = 24.0) in high, 56.5% (OR = 3.9) in moderate, and 25.0% (OR = 1) in low risk groups. SNP of IFN-gamma and TNF-alpha genes may contribute to the modulation of fibrosis in the intrahepatic bile duct wall in clonorchiasis patients.

Expression of IL-10, TGF-beta(1) and TNF-alpha in Cultured Keratinocytes (HaCaT Cells) after IPL Treatment or ALA-IPL Photodynamic Treatment

BACKGROUND

Depending on the light dose and concentration of photosensitizer for photodynamic treatment (PDT), a multitude of dose-related events are demonstrable in PDT-treated cells. Sublethal doses may result in the alteration of cytokine release and consequently modify immune actions, rather than cause cell death.

OBJECTIVE

The purpose of this study was to investigate cytokine expression in cultured HaCaT cells after intense pulse light (IPL) treatment or PDT utilizing 5-aminolevulinic acid (ALA) and IPL at sublethal doses.

METHODS

Cultured HaCaT cells were treated with either IPL only (4, 8 and 12 J/cm(2)) or ALA-IPL PDT (100micromol/L of ALA; 0, 4, 8, and 12 J/cm(2) of IPL). The expression of IL-10, TGF-beta(1) and TNF-alpha was investigated by reverse transcription-polymerase chain reaction and enzyme linked immunosorbent assay.

RESULTS

IL-10 protein increased up to 5.95-fold after IPL treatment and up to 2.85-fold after PDT. TGF-beta(1) mRNA and protein showed slight increases after both IPL treatment and PDT, of which the latter induced slightly larger increases. TNF-alpha mRNA and protein showed no induction or reduction after PDT.

CONCLUSION

Increased expressions of IL-10 and TGF-beta(1) was observed after PDT. The induction of IL-10 may contribute to the anti-inflammatory effect, which explains the therapeutic benefit of PDT for inflammatory dermatoses, and that of TGF-beta(1) may be related to the therapeutic effect for psoriasis. The finding that IL-10 induction was more marked after IPL treatment than after PDT suggests that other mechanisms than IL-10 induction in keratinocytes after PDT may participate in the anti-inflammatory effect of PDT.

Production of TGF-beta1 as a Mechanism for Defective Antigen-presenting Cell Function of Macrophages Generated in vitro with M-CSF

Background

Macrophages generated in vitro using macrophage-colony stimulating factor (M-CSF) and interleukin (IL)-6 from bone marrow cells (BM-Mp) are defective in antigen presenting cell (APC) function as shown by their ability to induce the proliferation of anti-CD3 mAb-primed syngeneic T cells. However, they do express major histocompatibility (MHC) class I and II molecules, accessory molecules and intracellular adhesion molecules. Here we demonstrate that the defective APC function of macrophages is mainly due to production of TGF-β1 by BM-Mp.

Methods

Microarray analysis showed that TGF-β1 was highly expressed in BM-Mp, compared to a macrophage cell line, B6D, which exerted efficient APC function. Production of TGF-β1 by BM-Mp was confirmed by neutralization experiments of TGF-β1 as well as by real time-polymerase chain reaction (PCR).

Results

Addition of anti-TGF-β1 monoclonal antibody to cultures of BM-Mp and anti-CD3 mAb-primed syngeneic T cells efficiently induced the proliferation of syngeneic T cells. Conversely, the APC function of B6D cells was almost completely suppressed by addition of TGF-β1. Quantitative real time-PCR analysis also confirmed the enhanced expression of TGF-β1 in BM-Mp.

Conclusion

The defective APC function of macrophages generated in vitro with M-CSF and IL-6 was mainly due to the production of TGF-β1 by macrophages.

The Relation Between Sox9, TGF-beta1, and Proteoglycan in Human Intervertebral Disc Cells

OBJECTIVE

The aim of this study is to elucidate the effects of transforming growth factor-beta (TGF-beta)1 and L-ascorbic acid on proteoglycan synthesis, and the relationship between Sox9, proteoglycan, and TGF-beta1 in intervertebral disc cells.

METHODS

Human intervertebral disc tissue was sequentially digested to 0.2% pronase and 0.025% collagenase in DMEM/F-12 media and extracted cells were cultured in 37, 5% CO(2) incubator. When intervertebral disc cells were cultured with TGF-beta1 or L-ascorbic acid, the production level of sulfated glycosaminoglycan (sGAG) was estimated by dimethyl methyleneblue (DMMB) assay. The changes of Sox9 mRNA and protein levels via TGF-beta1 were detected by RT-PCR and Western blot analysis in each.

RESULTS

The amount of sGAG was increased with the lapse of time during incubation, and sGAG content of pellet cultured cells was much larger than monolayer culture. When primary cultured intervertebral disc cells in monolayer and pellet cultures were treated by TGF-beta1 20 ng, sGAG content of experimental group was increased significantly compared to control group in both cultures. L-Ascorbic acid of serial concentrations (50-300 ug/ml) increased sGAG content of mono layer cultured intervertebral disc cells significantly in statistics. The co-treatment of TGF-beta1 and L-ascorbic acid increased more sGAG production than respective treatment. After treating with TGF-beta1, Sox9 mRNA and protein expression rates were significantly increased in disc cells compared with the control group.

CONCLUSION

This study suggests that TGF-beta1 would increase sulfated glycosaminoglycan (sGAG) and other proteoglycans such as versican by elevating Sox9 mRNA and protein expressions in order.

Effect of Jiazhu on α-SMA and TGF-β1 expression in rats with hepatic fibrosis

AIM: To investigate the effect of Jiazhu on α-SMA and TGF-β1 expression in the liver of rats with hepatic fibrosis and its anti-fibrosis mechanism.

METHODS: A model of rat hepatic fibrosis was induced by injecting 40% CCl4, which was interfered with high [2.0 g/(kg·d)], medium [1.0 g/(kg·d)] and low doses [0.5 g/(kg·d)] of Jiazhu. Hepatic function and serum TGF-β1 were examined. Expression of α-SMA and TGF-β1 was detected by immunohistochemistry and RT-PCR.

RESULTS: Compared with the model group, the levels of aspartate transaminase and alanine transaminase were significantly decreased in the high, medium and low Jiazhu dose groups. Total protein and albumin increased while serum bilirub and TGF-β1 were significantly reduced. The expression of α-SMA and TGF-β1 in liver tissue was decreased. The mRNA expression, stained area and gray scale of α-SMA and TGF-β1 in the high, medium and low Jiazhu dose groups were significantly different compared with the model group(α-SMA: 9.21 ± 1.12、12.63 ± 2.42、14.23 ± 1.57 vs 16.32 ± 2.14, P < 0.01、P < 0.01、P < 0.05; TGF-β1 mRNA: 5.58 ± 0.80、8.62 ± 1.16、11.92 ± 1.35 vs 14.57±1.59, P < 0.01、P < 0.01、P < 0.01), (dyeing area of α-SMA: 9.21% ± 1.29%、12.63% ± 1.44%、14.23% ± 1.41% vs 16.32% ± 1.75%, P < 0.01、P < 0.01、P < 0.05; dyeing area of TGF-β1: 5.31% ± 0.70%、8.37% ± 1.09%、11.92% ± 1.42% vs 14.47% ± 1.48%, P < 0.01、P < 0.01、P < 0.01), (gray scale of α-SMA: 91.29 ± 9.53、99.55 ± 11.83、107.18 ± 12.06 vs 116.44 ± 12.97, P < 0.01、P < 0.01、P < 0.05; gray scale of TGF-β1: 89.96 ± 9.64、106.92 ± 13.90、110.50 ± 12.91 vs 127.13 ± 14.88, P < 0.01、P < 0.01、P < 0.05).

CONCLUSION: Jiazhu can inhibit rat hepatic fibrosis induced by CCL₄.

In vitro healing of avascular meniscal injuries with fresh and frozen plugs treated with TGF-beta1 and IGF-1 in sheep

We studied the effect of freezing and inserting meniscal plugs in lesions generated in the avascular area of sheep menisci maintained in vitro, and whether the healing process can be improved by adding growth factors TGF-beta1 and IGF-1. Thirty six menisci obtained from healthy 3 months-old sheep were cultured in 6 well plates and holes were perforated in the avascular area. Meniscal plugs, either fresh or frozen at -20 degrees C for 1 month, were used to fill in the lesions, and then cultured in the presence or absence of TGF-beta1 or IGF-1 for 8 weeks. Samples stained with Massons trichrome were analyzed to evaluate the attachment of the plug and the cell density of the tissue. BrdU immunohistochemistry was performed to identify the proliferation of meniscal cells. Both growth factors improved considerably the cell density of implanted plugs. TGF-beta1 increased significantly the attachment of both fresh and frozen plugs, but it had no effect on meniscal cell proliferation. In contrast, IGF-1 had no effect on the attachment, but did increase significantly the number of proliferating cells in the surface of the host meniscus and the inserted plug. In conclusion, frozen plugs can survive if treated with either TGF-beta1 or IGF-1. The combination of TGF-beta1 and IGF-1 could aid in the repairing of the avascular meniscal injuries, as they are capable of promoting the attachment of tissue, and increasing the proliferation of meniscal cells.

Improving in vitro generated cartilage-carrier-constructs by optimizing growth factor combination

The presented study is focused on the generation of osteochondral implants for cartilage repair, which consist of bone substitutes covered with in vitro engineered cartilage. Re-differentiation of expanded porcine cells was performed in alginate gel followed by cartilage formation in high-density cell cultures. In this work, different combinations of growth factors for the stimulation of re-differentiation and cartilage formation have been tested to improve the quality of osteochondral implants. It has been demonstrated that supplementation of the medium with growth factors has significant effects on the properties of the matrix. The addition of the growth factors IGF-I (100 ng/mL) and TGF-β1 (10 ng/mL) during the alginate culture and the absence of any growth factors during the high-density cell culture led to significantly higher GAG to DNA ratios and Young’s Moduli of the constructs compared to other combinations. The histological sections showed homogenous tissue and intensive staining for collagen type II.

Serum Levels of TGF-beta1, TIMP-1 and TIMP-2 in Patients with Lumbar Spinal Stenosis and Disc Herniation

Study Design

The serum levels of transforming growth factor-beta 1 (TGF-β1), tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and TIMP-2 were measured by enzyme-linked immunosorbent assay.

Purpose

To compare the serum levels of TGF-β1, TIMP-1 and TIMP-2 between patients with lumbar spinal stenosis and disc herniation.

Overview of Literature

It has been reported that increased concentrations of TGF-β1, TIMP-1 and TIMP-2 in the ligamentum flavum might be a possible pathogenesis for ligamentum flavum hypertrophy in spinal stenosis. However, it is not determined whether this phenomenon in spinal stenosis is a local or systemic problem.

Methods

The concentrations of TGF-β1, TIMP-1 and TIMP-2 were quantitatively analyzed by ELISA in the ligamentum flavum and serum of patients with lumbar spinal stenosis (n=16) and disc herniation (n=16). The thickness of ligamentum flavum was measured on axial T1-weigted magnetic resonance image. The biochemical and radiological results were compared for the two conditions.

Results

The thickness of the ligamentum flavum was larger in patients with spinal stenosis compared with that with disc herniation (p=0.001). The mean concentrations of TGF-β1, TIMP-1, and TIMP-2 in the ligamentum flavum were significantly higher in patients with spinal stenosis than those with disc herniation (all, p < 0.05). However, the difference in serum levels of TGF-β1 (p=0.464), TIMP-1 (p=0.146) and TIMP-2 (p=0.794) was not significant between the lumbar spinal stenosis and disc herniation patients.

Conclusions

Despite increased levels of TGF-β1, TIMP-1, and TIMP-2 in the ligamentum flavum of spinal stenosis patients compared to disc herniation patients, the serum levels of TGF-β1, TIMP-1 and TIMP-2 were very similar in both groups. These results indicate that the role of TGF-β1, TIMP-1 and TIMP-2 on hypertrophy of the ligamentum flavum in spinal stenosis patients is a local phenomenon, not systemic.

Role of transforming growth factor-beta1-smad signal transduction pathway in patients with hepatocellular carcinoma

AIM: To explore the role of transforming growth factor-beta1 (TGF-β1)-smad signal transduction pathway in patients with hepatocellular carcinoma.

METHODS: Thirty-six hepatocellular carcinoma specimens were obtained from Qidong Liver Cancer Institute and Department of Pathology of the Second Affiliated Hospital of Nanjing Medical University. All primary antibodies (polyclonal antibodies) to TGF-β1, type II Transforming growth factor-beta receptor (TβR-II), nuclear factor-kappaB (NF-κB), CD34, smad4 and smad7,secondary antibodies and immunohistochemical kit were purchased from Zhongshan Biotechnology Limited Company (Beijing, China). The expressions of TGF-β1, TβR-II, NF-κB, smad4 and smad7 proteins in 36 specimens of hepatocellular carcinoma (HCC) and its adjacent tissue were separately detected by immunohistochemistry to observe the relationship between TGF-β1 and TβR-II, between NF-κB and TGF-β1, between smad4 and smad7 and between TGF-β1 or TβR-IIand microvessel density (MVD). MVD was determined by labelling the vessel endothelial cells with CD34.

RESULTS: The expression of TGF-β1, smad7 and MVD was higher in HCC tissue than in adjacent HCC tissue (P<0.01, P <0.05, P <0.01 respectively). The expression of TβR-IIand smad4 was lower in HCC tissue than in its adjacent tissue (P <0.01, P <0.05 respectively). The expression of TGF-β1 protein and NF-κB protein was consistent in HCC tissue. The expression of TGF-β1 and MVD was also consistent in HCC tissue. The expression of TβR-IIwas negatively correlated with that of MVD in HCC tissue.

CONCLUSION: The expressions of TGF-β1, TβR-II, NF-κB, smad4 and smad7 in HCC tissue, which are major up and down stream factors of TGF-β1-smad signal transduction pathway , are abnormal. These factors are closely related with MVD and may play an important role in HCC angiogenesis. The inhibitory action of TGF-β1 is weakened in hepatic carcinoma cells because of abnormality of TGF-β1 receptors (such as TβR-II) and postreceptors (such as smad4 and smad7). NF-κB may cause activation and production of TGF-β1.

Expression of TGF- b1, TGF-β1RII and NF-k B in hepatocellular carcinoma

AIM: To explore the expression of TGF-β1, TGF-β1RII and NF-κB in hepatocellular carcinoma (HCC) tiussues.

METHODS: Immunohistochemistry was used to detect the expression of TGF-β1, TGF-βRII and NF-κB protein in 30 HCC and the corresponding cancer-adjacent tissues. The expression of TGF-β1 mRNA was determined in 30 HCC and the corresponding cancer-adjacent tissues by in situ hybridization. Vascular endothelial cells were labeled with CD34 to observe the microvessel density (MVD). Then the relationships between TGF-β1 protein and MVD, TGF-β1RII protein and MVD, NF-κB and TGF-β1 protein as well as between TGF-β1 protein and mRNA were analyzed.

RESULTS: The expression of TGF-β1 protein and mRNA in HCC tissues were significantly higher than those in the cancer-adjacent tissues (Mean optical density: 0.0725±0.0102 vs 0.0442±0.0103, P < 0.01; 0.1043±0.0350 vs 0.0620±0.0225,P < 0.01). The MVD in HCC tissues was also markedly higher than that in the cancer-adjacent tissues (31.23±9.25 vs4.24±2.10, P < 0.01). The level of NF-κB expression was significantly higher than that in the cancer-adjacent tissues (0.0723±0.0210 vs 0.0305±0.0116, P < 0.01), while the level of TGF-βRII was lower (0.0402±0.0113 vs 0.0669±0.0157, P < 0.01). Obviously positive relationships existed between TGF-β1 protein and MVD (t = 3.25, P < 0.01), TGF-β1 mRNA and TGF-β1 protein (χ² = 8.21, P < 0.01) as well as between NF-κB and TGF-β1 protein (χ² = 9.075, P < 0.01), but the expression of TGF-β RIIprotein was negatively related to MVD.

CONCLUSION: TGF-β1, TGF-β1RII and NF-κB protein is abnormally expressed in HCC tissues and they are significantly related to MVD. They may play important roles in the angiogenesis of hepatocellular carcinoma. NF-κB may mediate the activation and production of TGF-β1.

Effect of TGF-β1 Stimulation on the Smad Signal Transduction Pathway of Human Peritoneal Mesothelial Cells

OBJECTIVE

To prove whether the SMAD signal transduction pathway in human peritoneal mesothelial cells (HPMCs) influenced the process of human peritoneal fibrosis stimulated by TGF-β1.

METHODS

HPMCs were isolated from normal human omentum and the third generation cells were stimulated by 5 ng/ml TGF-β1. Immunohistochemistry, Western blotting, ELISA and RT-PCR were employed to investigate the protein expression of p-Smad2/3 and the protein and mRNA expressions of SMAD 7, fibronectin (FN) and collagen-I (COL1).

RESULTS

The protein expression of p-Smad2/3 in HPMCs was remarkably increased 15 min (29% p-Smad2/3-positive cells) after TGF-β1 stimulation, peaking from 30 min (81%) to 1 h (84%) and dropping after 2 h (37%); Meanwhile, p-Smad2/3 mainly distributed in cytoplasm at 15 min, concentrated in cell nucleus and peri-nucleus from 30 min to 1 h, and distributed in cytoplasm again at 2 h. The protein expression of SMAD 7 in cells was obviously increased 24 h after TGF-β1 stimulation, peaking at 48 h. The mRNA expression of SMAD7 was time-dependently increased. The expressions of extracellular FN protein, intracellular FN mRNA, as well as intracellular COL1 protein and mRNA were significantly increased and all of them displayed time dependency.

CONCLUSIONS

The SMAD signal transduction pathway of HPMCs can be specifically activated by TGF-β1 and influence the process of human peritoneal fibrosis. The protein and mRNA expression of SMAD 7 (an inhibitor of SMAD pathway) are significantly increased as a result of feedback.