TGF-ß/Smad signaling pathway plays a crucial role in patulin-induced pro-fibrotic changes in rat kidney via modulation of slug and snail expression.

Patulin (PAT) is a mycotoxin that contaminates a variety of food and foodstuffs. Earlier in vitro and in vivo findings have indicated that kidney is one of the target organs for PAT-induced toxicity. However, no study has evaluated the chronic effects of PAT exposure at environmentally relevant doses or elucidated the detailed mechanism(s) involved. Here, using in vitro and in vivo experimental approaches, we delineated the mechanism/s involved in pro-fibrotic changes in the kidney after low-dose chronic exposure to PAT. We found that non-toxic concentrations (50 nM and 100 nM) of PAT to normal rat kidney cells (NRK52E) caused a higher generation of reactive oxygen species (ROS) (mainly hydroxyl (•OH), peroxynitrite (ONOO-), and hypochlorite radical (ClO-). PAT exposure caused the activation of mitogen-activated protein kinases (MAPKs) and its downstream c-Jun/Fos signaling pathways. Moreover, our chromatin immunoprecipitation (ChIP) analysis suggested that c-Jun/Fos binds to the promoter region of Transforming growth factor beta (TGF-ß1) and possibly induces its expression. Results showed that PAT-induced TGF-ß1 further activates the TGF-ß1/smad signaling pathways. Higher activation of slug and snail transcription factors further modulates the regulation of pro-fibrotic molecules. Similarly, in vivo results showed that PAT exposure to rats through gavage at 25 and 100 µg/kg b. wt had higher levels of kidney injury/toxicity markers namely vascular endothelial growth factor (VEGF), kidney Injury Molecule-1 (Kim-1), tissue inhibitor of metalloproteinase-1 (Timp-1), and clusterin (CLU). Additionally, histopathological analysis indicated significant alterations in renal tubules and glomeruli along with collagen deposition in PAT-treated rat kidneys. Overall, our data provide evidence of the involvement of ROS mediated MAPKs and TGF-ß1/smad pathways in PAT-induced pro-fibrotic changes in the kidney via modulation of slug and snail expression.

The cooperative effects of micro-grooved topography and TGF-ß1 on the vascular smooth muscle cell contractile protein expression of the mesenchymal stem cells.

Cell morphological changes induced by micro-grooved topography have been shown to be an important regulator of smooth muscle (SM) differentiation of mesenchymal stem cells (MSCs). In addition to the micro-grooved topography, transforming growth factor-ß1 (TGF-ß1) can also modulate MSCs differentiation towards smooth muscle cells (SMCs) through alterations in cell morphological characteristics. Thus, it can be hypothesized that substrate topography and TGF-ß1 may interact to facilitate differentiation of MSCs into SMCs. In this study, we investigated the time-course cooperative effects of substrate topography and TGF-ß1 in the regulation of SM differentiation of human MSCs. Western blotting, followed by image analysis, was performed to assess the protein expression of α-actin, h1-calponin and gelsolin. Three-way analysis of variance was employed to investigate the main effect of each independent variable, i.e. TGF-ß1 conditioning, substrate topography and culture time, along with the interactions of these variables. Each of TGF-ß1, substrate topography and culture time significantly affected the protein expression of α-actin, h1-calponin and gelsolin. Overall, TGF-ß1 conditioning of the cells and culturing the cells on the micro-grooved substrate resulted in greater protein expression of α-actin and h1-calponin, and lesser protein expression of gelsolin. In addition to the isolated effects of the variables, treatment type interacted with substrate topography and culture time to regulate the expression of the above-mentioned proteins. This study indicated the feasibility of promoting SM differentiation of human MSCs by simultaneous recruitment of micro-grooved topography and TGF-ß1. The findings could be of assistance when effective utilization of chemo-physical cues is needed to achieve functional SMC-like MSCs in vitro.

Silencing of Gal-7 inhibits TGF-ß1-induced apoptosis of human airway epithelial cells through JNK signaling pathway.

Apoptosis of epithelial cells is regarded as the initial pathological process of many lung diseases, including asthma. Previous studies have identified that galectin-7 (Gal-7), a regulator of apoptosis, was overexpressed in bronchial epithelial cells in asthma. However, the effect and mechanism of Gal-7 in the progression of asthma is still unclear. In this study, we investigated the expression and role of Gal-7 in the apoptosis of bronchial epithelial cells BEAS-2B upon TGF-ß1 stimulation. TGF-ß1 significantly induced apoptosis of BEAS-2B cells, as determined by flow cytometry. Western blot results revealed that the mRNA and protein expression of Gal-7 were obviously increased after TGF-ß1 stimulation. Small interfering RNA (siRNA)-mediated knockdown of Gal-7 abrogated TGF-ß1-evoked cell apoptosis. Simultaneously, increased Bcl-2 expression, decreased Bax expression and the cleavage of poly ADP-ribose polymerase (PARP) and caspase-3 activity were also monitored in TGF-ß1-treated cells after Gal-7 siRNA transfection. Gal-7 silence also inhibited TGF-ß1-induced c-Jun N-terminal kinase (JNK) phosphorylation in BEAS-2B cells. Furthermore, anisomycin, a specific activator for JNK, reversed the effect of Gal-7 siRNA on cell apoptosis induced by TGF-ß1. These results demonstrate that Gal-7 silence attenuates TGF-ß1-induced apoptosis in bronchial epithelial cells through the inactivation of JNK pathway. Therefore, Gal-7 may act as a potential target for asthma treatment.

Staphylococcus aureus induces TGF-ß1 and bFGF expression through the activation of AP-1 and NF-κB transcription factors in bovine mammary epithelial cells.

Staphylococcus aureus is a common Gram-positive pathogen that causes bovine mastitis, a persistent infection of the bovine mammary gland. Bovine mammary epithelial cells (BMEC) are important parenchymal cells of the bovine mammary gland. To better understand the importance of BMEC and the roles of the TLR-NF-κBand TLR-AP-1 signaling pathways in the regulation of S. aureus-associated mastitis and mammary fibrosis, BMEC cultured in vitro were stimulated with different concentrations of heat-inactivated S. aureus to analyze the gene and protein expression and production of toll-like receptor 2 (TLR2), toll-like receptor 4 (TLR4), transforming growth factor beta 1 (TGF-ß1), basic fibroblast growth factor (bFGF) as well as the protein expression of nuclear factor-kappa B (NF-κB) and activation protein-1 (AP-1) by means of quantitative polymerase chain reaction (qPCR) and western blotting, respectively. Specific NF-κB and AP-1 inhibitors were also used to investigate their effects on the regulation of TGF-ß1 and bFGF expression. The results indicated that, in addition to increasing mRNA expression and secretion of TLR2 and TLR4, S. aureus could also upregulate TGF-ß1 and bFGF mRNA expression and secretion through the activation of NF-κB and AP-1. The increase in TGF-ß1 and bFGF expression was shown to be inhibited by AP-1- and NF-κB-specific inhibitors. Taken together, S. aureus induces TGF-ß1 and bFGF expression through the activation of AP-1 and NF-κB in BMECs. This information offers new potential targets for the treatment of bovine mammary fibrosis.

Systemic expression of inflammatory mediators in patients with chronic rhinosinusitis and nasal polyps with and without Aspirin Exacerbated Respiratory Disease.

BACKGROUND: Systemic reactions are related to the pathogenesis of Aspirin Exacerbated Respiratory Disease (AERD). With this work we wanted to study the changes in the systemic levels of inflammatory mediators in both baseline and after oral aspirin challenge in patients with and without AERD. METHODS: Patients with nasal polyposis and asthma with AERD (n=20) and without (n=18) were orally challenged with aspirin in a single-blind placebo controlled study. Serum samples and urine were collected before and 6h after placebo and aspirin oral challenges. Serum levels of inflammatory mediators were assayed by using the Luminex technology and ELISA. The concentrations of 9-alpha, 11-beta prostaglandin F2, and leukotriene E4 (uLTE4) were measured in urine samples by ELISA. The expression of T-cell surface markers was analyzed in peripheral blood mononuclear cells isolated before and after the challenges. RESULTS: AERD patients showed significantly higher baseline levels of s-IL-5R-alpha, uLTE4 and percentage of CD4(+)CD25(+)CD127(pos) and CD4(+)CD45RA(-)CD45RO(+) but decreased levels of TGF-ß1 and number of CD4(+)CD25(+)CD127(neg) cells. Aspirin challenge induced the release of uLTE4, IL-6 and increased the number of CD4(+)CD45RA(-)CD45RO(+) memory T-cells only in AERD patients but failed to reduce the levels of sCD40L as observed in non-AERD subjects. Further, IL-8 and sIL-5R-alpha levels directly correlated with the PD20ASA and the effects of aspirin on IL-6 and number of memory T-cells was more pronounced in subjects showing more strong reaction (bronchial and nasal). CONCLUSIONS: AERD patients have a differential baseline inflammatory pattern that supports the role inflammation as underlying mechanism of the disease. Systemic response to oral aspirin challenge was related to an increase in serum IL-6 and the number of circulating memory T-cells in AERD patients.

Staphylococcus aureus induces TGF-ß1 and bFGF expression through the activation of AP-1 and NF-κB transcription factors in bovine mammary gland fibroblasts.

Staphylococcus aureus is a common Gram-positive pathogen that causes bovine mastitis, a persistent infection of the bovine mammary gland. To better understand the importance of bovine mammary fibroblasts (BMFBs) and the roles of the TLR-NF-κB and TLR-AP-1 signaling pathways in the regulation of S. aureus-associated mastitis and mammary fibosis, BMFBs cultured in vitro were stimulated with different concentrations of heat-inactivated S. aureus to analyze the gene and protein expression of toll-like receptor 2 (TLR2), toll-like receptor 4 (TLR4), transforming growth factor beta 1 (TGF-ß1), basic fibroblast growth factor (bFGF) as well as the protein expression of nuclear factor-kappa B (NF-κB) and activation protein-1 (AP-1) by means of quantitative polymerase chain reaction (qPCR) and western blotting, respectively. Specific NF-κB and AP-1 inhibitors were also used to investigate their effects on the regulation of TGF-ß1 and bFGF expression. The results indicated that, in addition to increasing mRNA and protein expression of TLR2 and TLR4, S. aureus could also upregulate TGF-ß1 and bFGF mRNA expression and secretion through the activation of NF-κB and AP-1. The increase in TGF-ß1 and bFGF expression was shown to be inhibited by AP-1- and NF-κB-specific inhibitors. Taken together, S. aureus induces TGF-ß1 and bFGF expression through the activation of AP-1 and NF-κB in BMFBs. This information offers new potential targets for the treatment of bovine mammary fibrosis.

Angiotensin II upregulates Kv1.5 expression through ROS-dependent transforming growth factor-beta1 and extracellular signal-regulated kinase 1/2 signalings in neonatal rat atrial myocytes.

Kv1.5 potassium channel represents a promising target for atrial fibrillation (AF) therapy. During AF, the renin-angiotensin system is markedly activated. Recent evidence indicates that angiotensin II (Ang II) can upregulate Kv1.5 channel, but the mechanism remains unknown. In this study, we report that Ang II-mediated transforming growth factor-beta1 (TGF-ß1)/Smad2/3 and extracellular signal-regulated kinase (ERK) 1/2 signalings are involved in atrial Kv1.5 expression. In neonatal rat atrial myocytes, quantitative PCR and Western blotting revealed that Ang II upregulated TGF-ß1, synapse-associated protein 97 (SAP97) and Kv1.5 expression in a time- and concentration-dependent manner. The Ang II-induced upregulation of Kv1.5, SAP97 and phosphorylated Smad2/3 (P-Smad2/3) were reversed by the Ang II type 1 (AT1) receptor antagonist losartan, an anti-TGF-ß1 antibody and the ERK 1/2 inhibitor PD98059 but not by the AT2 receptor antagonist PD123319. mRNA knockdown of either Smad2 or Smad3 blocked Ang II-induced expression of Kv1.5 and SAP97. These data suggest that AT1 receptor/TGF-ß1/P-Smad2/3 and ERK 1/2 signalings are involved in Ang II-induced Kv1.5 and SAP97 expression. Flow cytometry and Western blotting revealed that losartan and the anti-TGF-ß1 antibody diminished Ang II-induced reactive oxygen species (ROS) generation and that the antioxidants diphenyleneiodonium and N-acetyl cysteine inhibited Ang II-induced expression of P-Smad2/3, phosphorylated ERK (P-ERK) 1/2, Kv1.5, SAP97, suggesting that ROS participate in Kv1.5 and SAP97 regulation by modulating Ang II-induced P-Smad2/3 and P-ERK 1/2 expression. In conclusion, we demonstrate that ROS-dependent Ang II/AT1 receptor/TGF-ß1/P-Smad2/3 and Ang II/ERK 1/2 signalings are involved in atrial Kv1.5 and SAP97 expression. Antioxidants would be beneficial for AF treatment through inhibiting atrial Kv1.5 expression.

Co-delivery of pirfenidone and siRNA in ZIF-based nanoparticles for dual inhibition of hepatic stellate cell activation in liver fibrotic therapy.

Hepatic fibrosis, as a destructive liver disease, occurs due to activated hepatic stellate cells (HSCs) producing excessive extracellular matrix deposition. If left untreated, it could further deteriorate into cirrhosis and hepatoma with high morbidity and mortality. Currently, to break the dilemma of poor targeting efficiency on HSCs and limited effect of monotherapy, it is urgent to explore a precise and efficient treatment against liver fibrosis. In the present work, a novel multifunctional nanoplatform based on vitamin A (VA) modified zeolitic imidazolate framework-8 (ZIF-8) nanoparticles was designed for co-delivery of chemical drug (Pirfenidone) and genetic drug (TGF-ß1 siRNA) to achieve HSCs targeting mediated synergistic chemo-gene therapy against liver fibrosis. With the large specific surface area and acid-responsive degradation characteristics, ZIF-8 nanoparticles have great advantages to achieve high loading efficiency of Pirfenidone and enable acid-reactive drug release. After complexing siRNA, the prepared chemo-gene drug co-delivered nanocomplex (GP@ZIF-VL) proved excellent serum stability and effectively protected siRNA from degradation. Importantly, in vitro cell uptake and in vivo biodistribution demonstrated that VA functionalization markedly enhanced the delivery efficiency of GP@ZIF-VL nanocomplex into HSCs. As expected, GP@ZIF-VL significantly reduced extracellular matrix deposition and ameliorated hepatic fibrosis, as evidenced by decreased levels of liver enzymes in serum and a reduction in the hydroxyproline content in liver tissue. Therefore, GP@ZIF-VL nanocomplex displayed a bright future on the treatment of liver fibrosis with HSCs-targeting mediated chemo-gene synergetic therapy.

Evaluation of the flavonol-rich fraction of Rosa damascena in an animal model of liver fibrosis by targeting the expression of fibrotic cytokines, antioxidant/oxidant ratio and collagen cross-linking.

INTRODUCTION: The flavonoid-rich fraction of Rosa damascena (FRFRD) contains antioxidant and active compounds. Therefore, this study aimed to investigate the role of FRFRD, rich in quercetin and kaempferol, in liver fibrosis induced by CCl4. MATERIALS AND METHODS: The FRFRD fraction was separated and standardized by High-Performance Liquid Chromatography (HPLC) based on the levels of quercetin and kaempferol. Liver fibrosis was induced over CCl4 over 12 weeks in 30 male Wistar rats, and three concentrations of FRFRD were administered to them during the last four weeks. Subsequently, after evaluation of liver serum markers and fibrotic parameters, the relative expression of transforming growth factor-beta-1 (TGF-ß1), platelet-derived growth factor (PDGF), and lysyl oxidase homolog 2 (Loxl2) genes were assessed, along with the measurement of lysyl oxidase activity and oxidative markers. RESULTS: Fibrotic markers demonstrated progressive recovery of liver damage in the treated group compared to the non-treatment group (p < 0.01). These results were accompanied by a significant decrease in the expression of TGF-ß1, PDGF, and Loxl2 genes, as well as, a reduction in lysyl oxidase activity (p < 0.001). The antioxidant effects of the treatment were observed through a significant decrease in malondialdehyde (MDA) levels and an increase in catalase enzyme (CAT) and glutathione peroxidase (GPx) activity in the treatment group compared to the fibrotic group (p < 0.01). CONCLUSION: The flavonoid-rich fraction of Rosa damascena ameliorates liver damage by affecting collagen cross-linking and lowering oxidative and inflammatory levels.

[The 869C>T And 915G>C Polymorphisms of TGF-ß1 and Type 1 Diabetic Retinopathy in the Algerian Population]. / Polymorphismes 869C> T et 915 G>C du TGF-ß1 dans la rétinopathie du diabète de type 1 chez la population algérienne.

INTRODUCTION: Diabetic retinopathy (DR) is characterized by chronic low-grade inflammation in which the effects of genetic factors is well established. The objective of our study is to explore an association of the 869C>T and 915G>C polymorphisms of the TGF-ß1 gene with type 1 diabetic retinopathy in the Algerian population. PATIENTS AND METHODS: A case-control study was carried out in which the SNPs 869C>T and 915G>C of the TGF-ß1 gene were analysed by the PCR-SSP technique. We compared the distribution of allelic and genotypic frequencies between patients with and without retinopathy and looked for an association between these polymorphisms and certain clinical characteristics of and risk factors for diabetic retinopathy. RESULTS: A significant increase in the frequencies of the C allele (P=0.03) and GG genotype (P=0.007) of the 915 G>C polymorphism were found, respectively, in patients without and with retinopathy. However, no significant difference was found for allelic and genotypic frequencies of the 869C>T SNP (all P>0.05) or associations between genotypes and clinical characteristics or risk factors for DR. CONCLUSION: Our preliminary results suggest that the C allele of the 915 G>C polymorphism of TGF-ß1 is protective against type 1 diabetic retinopathy in the Algerian population, while the GG genotype could confer susceptibility to it.

The Role of Smad2 in Transforming Growth Factor ß1-Induced Hypertrophy of Ligamentum Flavum.

BACKGROUND: Hypertrophy of the ligamentum flavum (LF) contributes to the development of spinal stenosis. Smad proteins can mediate the fibrogenesis activity through the transforming growth factor ß1 (TGF-ß1) pathway, but which Smad protein plays a more important role in the hypertrophy process of LF is unclear. METHODS: The LF samples were obtained from 50 patients. After the LF cells (LFCs) were cultured, small interfering ribonucleic acid (siRNA) that target human phosphorylated-Smad2, 3, or 4 (p-Smad2,3,4) genes was transfected into LFCs. Next, proteins from cells were extracted and the protein levels of Smad2, Smad3, and Smad4 were detected by Western blot. The messenger ribonucleic acid level of TGF-ß1 was measured by real-time polymerase chain reaction (PCR). Furthermore, an enzyme-linked immunosorbent assay was performed to test the impact of Smad2 downstream of the TGF-ß1 signaling pathway. RESULTS: Degeneration of the LF was characterized by an increase in disorganized elastic fibers and fibrotic transformation by extracellular collagen deposition. The gene expression analysis of fibrotic genes in LFCs showed that knockdown of phosphorylated-Smad2 by siRNA significantly reduced the protein expression level of TGF-ß1 compared with other groups. The enzyme-linked immunosorbent assay suggested that the protein expression level of Smad2 can influence the downstream events of TGF-ß1 signaling pathway in the LFCs. CONCLUSIONS: Our findings suggest that Smad2 plays a potential role in the pathologic development of hypertrophy of LF. We also found that Smad2 knockdown by Smad-siRNA can influence the TGF-ß1 signaling pathway through decreasing expression of TGF-ß1, tumor necrosis factor α, and nuclear factor κb.

The role of miR-328 in high glucose-induced endothelial-to-mesenchymal transition in human umbilical vein endothelial cells.

AIMS: Endothelial-to-mesenchymal transition (EndMT) contribute to diabetic cardiac fibrosis, the underlying mechanisms are poorly understood. In the study, we aimed to investigate the role of miR-328 in EndMT mediated by high glucose (HG) and the signaling pathways implicated in human umbilical vein endothelial cells (HUVECs). MATERIALS AND METHODS: EndMT of HUVECs was determined by immunofluorescent staining and western blot of the markers CD31 and α-SMA. Real-time polymerase chain reaction was used to detect mRNA expression of miR-328 and transforming growth factor ß1 (TGF-ß1). SB431542 was used to study the relation of miR-328 and TGF-ß1 during EndMT induced by HG. Over-expression and inhibition of miR-328 were achieved by transduction of miR-328 and antagomiR-328. The effects of miR-328 on expression of type I and III collagen, p-MEK1/2, p-ERK1/2 were examined by Western blot. KEY FINDINGS: The level of miR-328 was significantly up-regulated in HG-induced EndMT. MiR-328 showed the independent capability of inducing EndMT, which was not related to TGF-ß1, and this effect was abrogated by antagomiR-328. MiR-328 affected type I collagen in a time- and dose-dependent manner and enhanced protein expression of type I and III collagens. Further investigation displayed that a significantly higher expression of p-MEK1/2 and p-ERK1/2 in HUVECs transduced with miR-328, and a lower expression of p-MEK1/2 and p-ERK1/2 in cells transduced with antagomiR-328. SIGNIFICANCE: These results suggest a novel role for miR-328 in HG-induced EndMT, MEK1/2-ERK1/2 pathway is likely to be involved in the associated effects. Our findings may suggest antagomiR-328 as an alternative agent in prevention of HG-induced EndMT.

Assessment of the possible roles of SB-269970 versus ketanserin on carbon tetrachloride-induced liver fibrosis in rats: Oxidative stress/TGF-ß1-induced HSCs activation pathway.

BACKGROUND: In liver fibrosis, a major morbid and mortal disease, oxidative stress motivation of hepatic stellate cells (HSCs)-into myofibroblasts terminated in collagen deposition remain the key pathophysiological deal. Serotonin (5-HT) through its HSCs-expressed receptors, especially 5-HT2A and 7, shows crucial events in fibrogenesis of chronic liver diseases. Molecular hepatic oxidative stress-fibrotic roles of 5-HT2A and 7 receptors antagonists (ketanserin and SB-269970 respectively) are still a challenging issue. METHODS: Seven groups of adult male Wistar rats (n=10) were used. A carbon tetrachloride (CCl4) solution was injected intraperitoneally twice weekly for 6 weeks. On the 7th week, rats developed liver fibrosis were treated either by ketanserin (1mg/kg/day, ip) or SB-269970 (2mg/kg/day, ip) for 14days. Survival rates, and serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels in addition to hepatic malondialdehyde (MDA) and reduced glutathione (GSH) levels, superoxide dismutase (SOD) and catalase (CAT) activities, and transforming growth factor-beta1 (TGF-ß1) and procollagen type I N-terminal propeptide (PINP) levels, beside the hepatic histopathological fibrotic changes, were evaluated. RESULTS: In CCl4-challenged rats, each therapeutic approach showed significant reductions in elevated serum ALT, and AST levels, hepatic MDA, TGF-ß1, and PINP levels, and histopathological hepatic fibrotic scores as well as significant elevations in survival rates, reduced hepatic GSH levels, and SOD, and CAT activities. Remarkably, significant ameliorative measurements were observed in SB-269970 treated group. CONCLUSION: Blockade of 5-HT2A and 7 receptors each alone could be a future reliable therapeutic approach in liver fibrosis through a reduction in oxidative stress/TGF-ß1-induced HSCs activation pathway.

Activation of AMPK Attenuated Cardiac Fibrosis by Inhibiting CDK2 via p21/p27 and miR-29 Family Pathways in Rats.

Cardiac fibrosis is pathological damage associated with nearly all forms of heart disease. AMP-activated protein kinase (AMPK) is an evolutionary conserved energy-sensing enzyme. Emerging evidences indicate that AMPK plays an important role in cardiac fibrosis and cell proliferation. However, less is known about the detailed mechanism of AMPK activation on cardiac fibrosis. In this study, we found the AMPK activation improved the impaired cardiac function of cardiac fibrosis rats and decreased interstitial fibrosis. Further results indicated AMPK activation promoted p21 and p27 and inhibited CDK2 and cyclin E protein expressions both in vivo and in vitro. Moreover, AMPK activation repressed downstream transcription factor hepatocyte nuclear factor 4 alpha (HNF-4α) expression and decreased the binding of HNF-4α to TGF-ß1 promoters, which eventually resulted in TGF-ß1 downregulation and miR-29 family upregulation. Furthermore, miR-29, in turn, inhibited the progression of cardiac fibrosis through suppressing its target CDK2. Taken together, activation of AMPK, on the one hand, upregulated p21 and p27 expression, further inhibited CDK2 and cyclin E complex, and finally suppressed the progression of cardiac fibrosis, and, on the other hand, repressed HNF-4α expression, further downregulated the activity of TGF-ß1 promoter, promoted miR-29 expression, and finally prevented the development of cardiac fibrosis.

Fluoride potentiates tubulointerstitial nephropathy caused by unilateral ureteral obstruction.

The contamination of ground water by fluoride has been reported worldwide. Most fluoride (approximately 70%) is filtered by the kidneys; humans or experimental animals with renal damage therefore may be more affected by fluoride exposure than those with normal kidney function. Tubulointerstitial fibrosis, which involves macrophage-promoted extracellular matrix production and myofibroblast migration, can be induced in rats by unilateral ureteral obstruction (UUO). We examined the effects of fluoride exposure on tubulointerstitial fibrosis in the obstructed kidney of UUO rats. The left ureters of 6-week-old male rats were ligated using silk sutures. Fluoride was then administered for 2 weeks at doses of 0, 75, and 150ppm in the drinking water. Real-time polymerase chain reaction was performed to analyze transforming growth factor beta 1 (TGF-ß1) transcription; histological and immunohistochemical staining were used to identify positive areas within the renal cortex and staining-positive cells by image analysis. Significant increases were observed in the obstructed kidneys of UUO rats exposed to 150ppm fluoride (compared to 0ppm) for areas or number of cells that stained with Masson trichrome or with antibodies against collagen type I, alpha-smooth muscle actin (α-SMA, a myofibroblast marker), ED1, ED2, and ED3 (macrophage markers), and TGF-ß1. Taken together, these observations suggested that fluoride exacerbates tuburointerstitial nephropathy resulting from UUO, and that this effect occurs via activation of the M2 macrophage-TGF-ß1-fibroblast/myofibroblast-collagen synthesis pathway.

Evaluation of breviscapine on prevention of experimentally induced abdominal adhesions in rats.

BACKGROUND: Adhesion formation, which results from mechanical peritoneal damage, tissue ischemia, or the presence of foreign materials, is a complicated process. The formation of adhesions is associated with inflammatory response and extracellular matrix deposition in response to injury. Although the pathophysiology of adhesion formation is widely understood, an absolute solution to this problem does not exist yet. As a main component of Erigeron breviscapus, breviscapine has exhibited the ability of anti-inflammatory and antifibrosis on many diseases. The purpose of this study was to investigate the effect of breviscapine on the development of postoperative intra-abdominal adhesions in Wistar rats. METHODS: Abdominal adhesions were induced by scraping the cecum in rats. Various dosages of breviscapine drugs were administered for 10 days after surgery. On the 11th day after surgery, the levels of interleukin (IL) 18, IL-6, tumor necrosis factor α in blood serum and transforming growth factor ß1 (TGF-ß1), connective tissue growth factor, tissue plasminogen activator (tPA), plasminogen activator inhibitor 1 (PAI-1) in peritoneal fluid were determined by enzyme linked immunosorbent assay. The expression of Smad7 and TGF-ß1 in rat cecum tissue was evaluated by Western blot analysis. Grades of intestinal adhesion were ranked by macroscopic observation. RESULTS: The intraperitoneal administration of breviscapine is effective on the prevention of the formation of postoperative adhesions in rats. Breviscapine decreased the levels of IL-18, IL-6, and tumor necrosis factor-α in blood serum and TGF-ß1, connective tissue growth factor, PAI-1 in peritoneal fluid. But the levels of tPA and the ratio of tPA and PAI-1 in peritoneal fluid were increased. In addition, breviscapine significantly inhibited the expression of TGF-ß1 and increased the level of Smad7 in the rat cecum tissue. CONCLUSIONS: These results suggested that intraperitoneal administration of breviscapine was effective in preventing intra-abdominal adhesion formation in rats. Breviscapine appears to have synergetic effects which could decrease fibrosis by inhibiting inflammation, upregulating peritoneal fibrinolytic activity and regulating the TGF and/or Smad signaling pathway. These data indicated a potential new therapeutic use of breviscapine on adhesion prevention.

TGF-ß1 and contact mediated suppression by CD4+CD25+CD127- T regulatory cells of patients with self-limiting hepatitis E.

BACKGROUND AND AIM: Literature on the role of Regulatory T cells (Tregs) in acute viral infections is limited. Having established that the Tregs in self-limiting hepatitis E infection are elevated and functional, this study has focused on characterizing the specificity, phenotypes and identifying the molecules or factors responsible for enhancement of Treg cells and abrogation of Treg-mediated suppression in hepatitis E. METHODS: HEV rORF2p specific (a) Treg frequency, subset analysis and expression of surface and intracellular markers on Tregs and CFSE based functional analysis by flow cytometry (b) key cytokines quantification by multiplex (c) suppressive functional assay in the presence of anti-TGF-ß1 or anti-IL-10 or both antibodies or Transwell insert or in combination were performed on samples from 58 acute patients (AVH-E), 45 recovered individuals from hepatitis E and 55 controls. RESULTS: In AVH-E, the increased frequencies of Tregs and Teff cells were HEV rORF2p specific and Treg cells were of effector memory phenotype. Higher expressions of HEV rORF2p stimulated CTLA-4, GITR, PD1L, CD103, CD39, TLR2 and TGF-ß1 molecules on Tregs of AVH-E were observed. Tregs produced TGF-ß1 and inhibited the secretion of IFN-γ. Transwell insert and cytokines blocking assays indicated Tregs mediated suppression in AVH-E patients is majorly TGF-ß1 mediated and partly cell-cell contact mediated. CONCLUSION: Overall, we have identified beneficial involvement of HEV specific, functional Tregs and TGF-ß1 as the regulatory molecule responsible for enhancement of Tregs in self-limiting HEV infection. Therefore, use of TGF-ß1 as a possible supplement for boosting Treg response in recovery from severe hepatitis E needs evaluation.

Compound Astragalus and Salvia miltiorrhiza extracts modulate MAPK-regulated TGF-ß/Smad signaling in hepatocellular carcinoma by multi-target mechanism.

ETHNOPHARMACOLOGICAL RELEVANCE: Astragalus membranaceus Bunge (Leguminosae) and Salvia miltiorrhiza Bunge (Lamiaceae) are two important Chinese herbs with a long history of extensive ethnobotanical usage in the treatment of liver-related diseases over many centuries. Presently, these two herbs are being used either as a single herbal formulation or a composite formula for the treatment of liver related conditions. In response, recent studies on these two herbs have focused on elucidating their mechanisms of action, particularly with regards to their anti-hepatocarcinogenic effects. Previously, we have reported that Compound Astragalus and Salvia miltiorrhiza extract (CASE), a synergized composite extract from Astragalus membranaceus and Salvia miltiorrhiza ameliorates liver fibrosis and hepatocellular carcinoma (HCC) by modulating the TGF-ß/Smad pathway. Meanwhile, MAPK activation and MAPK-dependent linker phosphorylation of Smad2/3 and their preferential nuclear import are crucial for overall oncogenic role of TGF-ß/Smad signaling in HCC. To elucidate further, we studied the effect of CASE on the MAPK pathway and how it affects MAPK-dependent regulation of TGF-ß/Smad signaling using both cell and animal models of HCC. MATERIALS AND METHODS: We used immunofluorescence and western blot techniques to monitor effect of CASE on the activation of the MAPKs (pERK, pJNK and pp38) in TGF-ß1-stimulated hepatic stellate cells (HSCs), HepG2 cells and also diethylnitrosamine (DEN)-induced HCC in rats. Also phosphorylation and subcellular distribution of pSmad2/3, Smad4 and Imp7/8 in TGF-ß1-stimulated HSC and HepG2 cells were monitored. The expression of pERK, pJNK, pp38 and PAI-1 gene were monitored by using western blot technique. The effect of CASE on domain-specific phosphorylation of Smad2/3 and their subcellular distribution, and the expression of Smad4 and its subcellular distribution in TGF-ß1-stimulated HSCs and HepG2 cells were evaluated by using immunofluorescence technique. And the expression of Imp7/8 and their subcellular distribution were assessed by both immunofluorescence and western blot techniques, while PAI-1 gene expression was assessed by western blot RESULTS: In vitro, CASE in a concentration-dependent manner increased the expression of pp38 but decreased the expression of pERK and pJNK; however, in vivo, CASE in a dose dependent manner decreased the expression of pERK, pJNK as well as pp38. Also, CASE concentration dependently inhibited pSmad2C/L, pSmad3L, Smad4, Imp7/8 and their nuclear import; it had no effect on pSmad3C in HepG2 cells; significantly decreased PAI-1 gene expression in both in vitro and in vivo. CONCLUSIONS: CASE blocked MAPK activation, MAPK-dependent linker phosphorylation of Smad2/3, Smad4 expression, Imp7 expression and their nuclear import leading to significant down-regulation of PAI-1 gene expression; further highlighting the multi-target anti-HCC effect of CASE and its potential drug candidature.

Evaluation of ligustrazine on the prevention of experimentally induced abdominal adhesions in rats.

OBJECTIVE: To determine the effects of ligustrazine on the prevention of postoperative intra-abdominal adhesions in rats. MATERIALS AND METHODS: Abdominal adhesions were induced by scraping the cecum of rats. Various dosages of ligustrazine were administered for 10 days after surgery. Grades of abdominal adhesions were ranked by macroscopic observation on the 11th day after surgery. Meanwhile, the levels of IL-1ß, IL-6, TNF-a in blood serum and TGF-ß1, CTGF in peritoneal fluid were determined by ELISA assay. In the cell experiment, the secretion of FN and CTGF undergoing stimulation with TGF ß1 in the culture fluid of rat peritoneal mesothelial cells (RPMC) were measured by ELISA assay. And the expression of Smad7 and p-smad 2/3 in RPMC were evaluated by western blot analysis. RESULTS: Ligustrazine remarkably alleviated the adhesions at the dose of 30 mg/kg and 60 mg/kg compared with the non-treated surgery group (p < 0.05). Ligustrazine decreased the levels of IL-1ß, IL-6, TNF-α in blood serum and the expression of TGF-ß1, CTGF in the peritoneal fluid in dose-dependent manner. In the cell experiment, ligustrazine markedly attenuated TGF-ß1 induced upregulation of FN and CTGF in RPMC. Meanwhile, ligustrazine significantly inhibited the expression of pSmad 2/3 and increased the level of Smad7 in the RPMC. CONCLUSIONS: Ligustrazine is a potent postoperative adhesion preventer by inhibiting inflammation and regulating the TGF/Smad signaling pathway.

Role of eukaryotic translation initiation factor 3a in bleomycin-induced pulmonary fibrosis.

Eukaryotic translation initiation factor 3a (eIF3a) is a multifunctional protein and plays an important role in regulation of cellular function including proliferation and differentiation. In the present study, we tested the function of eIF3a in pulmonary fibrosis. Pulmonary fibrosis was induced by intratracheal instillation of bleomycin (5mg/kg) in rats. Primary pulmonary fibroblasts were cultured for proliferation investigation by BrdU incorporation method and flow cytometry. The expression/level of eIF3a, TGF-ß1, ERK1/2 and α-SMA were analyzed by ELISA, real-time PCR or western blot. Results showed that the expression of eIF3a was obviously increased in lungs of pulmonary fibrosis rats accompanied by up-regulation of α-SMA and collagens. In cultured pulmonary fibroblasts, application of exogenous TGF-ß1 induced cell proliferation and differentiation concomitantly with up-regulation of eIF3a expression and ERK1/2 phosphorylation. The effects of TGF-ß1-induced proliferation of fibroblasts and up-regulation of α-SMA were abolished by eIF3a siRNA. TGF-ß1-induced eIF3a expression was reversed in the presence of PD98059, an inhibitor of ERK1/2. These findings suggest that eIF3a plays an important role in bleomycin-induced pulmonary fibrosis by regulating pulmonary fibroblasts׳ function, and up-regulation of eIF3a induced by TGF-ß1 is mediated via the ERK1/2 pathway.