Salvianolate ameliorates inflammation and oxidative stress in high-glucose induced HK-2 cells by blocking TGF-ß/Smad signal pathway.

The objective of this research is to assess how salvianolate impacts inflammation and oxidative stress in a laboratory setting, as well as to investigate the underlying mechanisms. HK-2 cells were subjected to different treatments, including normal glucose, mannitol, high glucose and high glucose plus salvianolate. Cell proliferation, death, MDA levels, IL-1ß, IL-6, TNF-α, MCP-1 concentrations, ROS levels, MMP, MPTP and ATP levels were assessed using various kits. The protein expressions of NOX4, TGF-ß1, P-Smad2, P-Smad3, Smad4 and Smad7 were ascertained through western blot analysis. Our results indicated salvianolate could reduce the release of IL-1ß, IL-6, TNF-α, as well as MCP-1, alleviate the levels of oxidative stress markers NOX4 and MDA, and improve mitochondrial function by increasing MMP and ATP levels while reducing ROS and MPTP opening. Furthermore, salvianolate inhibited the TGF-ß1/Smad2, Smad3 signaling pathway, suppressed Smad4 expression and increased Smad7 expression. Salvianolate seems to mitigate inflammation and oxidative stress through a variety of mechanisms. These discoveries offer valuable understanding into the possible mechanisms by which salvianolate may be employed in the treatment of diabetic nephropathy.

F127-SE-tLAP thermosensitive hydrogel alleviates bleomycin-induced skin fibrosis via TGF-ß/Smad pathway.

BACKGROUND: Skin fibrosis affects the normal function of the skin. TGF-ß1 is a key cytokine that affects organ fibrosis. The latency-associated peptide (LAP) is essential for TGF-ß1 activation. We previously constructed and prepared truncated LAP (tLAP), and confirmed that tLAP inhibited liver fibrosis by affecting TGF-ß1. SPACE peptide has both transdermal and transmembrane functions. SPACE promotes the delivery of macromolecules through the stratum corneum into the dermis. This study aimed to alleviate skin fibrosis through the delivery of tLAP by SPACE. METHODS: The SPACE-tLAP (SE-tLAP) recombinant plasmid was constructed. SE-tLAP was purified by nickel affinity chromatography. The effects of SE-tLAP on the proliferation, migration, and expression of fibrosis-related and inflammatory factors were evaluated in TGF-ß1-induced NIH-3T3 cells. F127-SE-tLAP hydrogel was constructed by using F127 as a carrier to load SE-tLAP polypeptide. The degradation, drug release, and biocompatibility of F127-SE-tLAP were evaluated. Bleomycin was used to induce skin fibrosis in mice. HE, Masson, and immunohistochemistry were used to observe the skin histological characteristics. RESULTS: SE-tLAP inhibited the proliferation, migration, and expression of fibrosis-related and inflammatory factors in NIH-3T3 cells. F127-SE-tLAP significantly reduced ECM production, collagen deposition, and fibrotic pathological changes, thereby alleviating skin fibrosis. CONCLUSION: F127-SE-tLAP could increase the transdermal delivery of LAP, reduce the production and deposition of ECM, inhibit the formation of dermal collagen fibers, and alleviate the progression of skin fibrosis. It may provide a new idea for the therapy of skin fibrosis.

The SGLT2 inhibitor empagliflozin inhibits skeletal muscle fibrosis in naturally aging male mice through the AMPKα/MMP9/TGF-ß1/Smad pathway.

ABSTACT: With advancing age, the incidence of sarcopenia increases, eventually leading to a cascade of adverse events. However, there is currently a lack of effective pharmacological treatment for sarcopenia. Sodium-glucose co-transporter 2 inhibitor (SGLT2i) empagliflozin demonstrates anti-fibrotic capabilities in various organs. This study aims to determine whether empagliflozin can improve skeletal muscle fibrosis induced by sarcopenia in naturally aging mice. A natural aging model was established by feeding male mice from 13 months of age to 19 months of age. A fibrosis model was created by stimulating skeletal muscle fibroblasts with TGF-ß1. The Forelimb grip strength test assessed skeletal muscle function, and expression levels of COL1A1, COL3A1, and α-SMA were analyzed by western blot, qPCR, and immunohistochemistry. Additionally, levels of AMPKα/MMP9/TGFß1/Smad signaling pathways were examined. In naturally aging mice, skeletal muscle function declines, expression of muscle fibrosis markers increases, AMPKα expression is downregulated, and MMP9/TGFß1/Smad signaling pathways are upregulated. However, treatment with empagliflozin reverses this phenomenon. At the cellular level, empagliflozin exhibits similar anti-fibrotic effects, and these effects are attenuated by Compound C and siAMPKα. Empagliflozin exhibits anti-fibrotic effects, possibly associated with the AMPK/MMP9/TGFß1/Smad signaling pathways.

Poly-L-Lactic acid increases collagen gene expression and synthesis in cultured dermal fibroblast (Hs68) through the TGF-ß/Smad pathway.

OBJECTIVE: Poly-L-Lactic Acid (PLLA) is a synthetic polymer which possesses biocompatible and biodegradable properties, and is widely used in the clinical filler material. This study focuses on the potential role of PLLA on the collagen production of dermal fibroblasts and its mechanism. METHODS: The dermal fibroblast Hs60 was treated with different concentration of PLLA. RT-qPCR was conducted for the determination of mRNA levels of collagen type I (COL1) alpha 1 (COL1A1), COL1 alpha 2 (COL1A2), elastin, matrix metalloproteinase 1 (MMP-1), tissue inhibitor of metalloproteinase 1 (TIMP-1), and TIMP-2. Procollagen Type I C-peptide (PIP) enzyme immunoassay (EIA) Kit assay was carried out to analyze procollagen production. Western Blot was employed to examine the effect of PLLA and transforming frown factor (TGF-ß) receptor-specific inhibitor (SB431542) on protein levels of COL1A1 and TGF-ß/Smad signaling pathway related proteins. RESULTS: With the increase of PLLA concentration, the production of procollagen gradually increased, and both protein and mRNA levels of COL1A1 and COL1A2 gradually increased (p < 0.001). Elevated PLLA concentrations increased elastin, TIMP-1, and TIMP-2 levels and attenuated MMP-1 expression. PLLA increased TGF-ß levels in a dose-dependently manner. p-Smad2 and p-Smad3 protein levels were also increased by PLLA, but the influences were reversed by SB431542 (p < 0.001). Similarly, increased levels of COL1A1, COL1A2, TIMP-1, and TIMP-2 caused by PLLA were significantly inhibited by SB431542, whereas MMP-1 was typically elevated (p < 0.001). CONCLUSION: Poly-L-Lactic Acid promotes the collagen production of dermal fibroblasts by activating the TGF-ß/Smad signaling pathway. The findings may lay a foundation for clinical material applications of PLLA.

Oroxylin A inhibits the migration of hepatocellular carcinoma cells by inducing NAG-1 expression.

Hepatocellular carcinoma (HCC), the most prevalent liver cancer, is considered one of the most lethal malignancies with a dismal outcome mainly due to frequent intrahepatic and distant metastasis. In the present study, we demonstrated that oroxylin A, a natural product extracted from Scutellaria radix, significantly inhibits transforming growth factor-beta1 (TGF-ß1)-induced epithelial-mesenchymal transition (EMT) and metastasis in HCC. Oroxylin A blocked the TGF-ß1/Smad signaling via upregulating the non-steroidal anti-inflammatory drug-activated gene-1 (NAG-1) expression. Oroxylin A promoted NAG-1 transcription by regulating the acetylation of CCAAT/enhancer binding protein ß (C/EBPß), a transcription factor that binds to the NAG-1 promoter. In terms of the underlying mechanism, oroxylin A may interact with histone deacetylase 1 (HDAC1) by forming hydrogen bonds with GLY149 residue and induce proteasome-mediated degradation of HDAC1 subsequently impairing HDAC1-mediated deacetylation of C/EBPß and promoting the expression of NAG-1. Taken together, our findings revealed a previously unknown tumor-suppressive mechanism of oroxylin A. Oroxylin A should be further investigated as a potential clinical candidate for inhibiting HCC metastasis.

Hesperetin regulates transforming growth factor-ß1/Smads pathway to suppress epithelial-mesenchymal transition -mediated invasion and migration in cervical cancer cell.

Hesperetin is an abundant flavonoid in citrus fruits, and be confirmed to possess a chemo-preventive effect on cancer. Migration and invasion are the main causes of death of cervical cancer patients, in which epithelial-mesenchymal transition (EMT) can directly contribute to malignant phenotypes of tumor cells. The present study aims to investigate the inhibitory effect of hesperetin on EMT-mediated invasion and migration in cervical cancer cells through transforming growth factor-ß1 (TGF-ß1)/Smads pathway. Cell viability, cell migration and invasion ability, and cell morphology were evaluated and monitored using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assays, Transwell assays and optical microscope, respectively. The change of EMT marker protein E-cadherin and N-cadherin was assessed by immunofluorescence assay, whereas the protein expression of EMT bio-marker and TGF-ß1/Smads pathway were detected through western blot analysis. In conclusion, hesperetin can suppress EMT-mediated invasion and migration of cervical cancer cells by inhibiting abnormal activation of TGF-ß1/Smads pathway. The study provides an experimental basis for the prevention of the invasion and migration of cervical cancer.

MGMT-inhibitor in combination with TGF-ßRI inhibitor or CDK 4/6 inhibitor increases temozolomide sensitivity in temozolomide-resistant glioblastoma cells.

BACKGROUND: Glioblastoma (GB) remains an incurable and deadly brain malignancy that often proves resistant to upfront treatment with temozolomide. Nevertheless, temozolomide remains the most commonly prescribed FDA-approved chemotherapy for GB. The DNA repair protein methylguanine-DNA methyl transferase (MGMT) confers resistance to temozolomide. Unsurprisingly temozolomide-resistant tumors tend to possess elevated MGMT protein levels or lack inhibitory MGMT promotor methylation. In this study, cultured human temozolomide resistance GB (43RG) cells were introduced to the MGMT inhibitor O6-benzylguanine combined with temozolomide and either LY2835219 (CDK 4/6 inhibitor) or LY2157299 (TGF-ßRI inhibitor) seeking to overcome GB treatment resistance. METHODS: Treatment effects were assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, western blot, cell viability, and cell cycle progression. RESULTS: Our in vitro study demonstrated that sequential treatment of O6-Benzylguanine with either LY2385219 or LY2157299-enhanced temozolomide enhanced sensitivity in MGMT+ 43RG cells. Importantly, normal human neurons and astrocytes remained impervious to the drug therapies under these conditions. Furthermore, LY2835219 has additional anti-proliferative effects on cell cycling, including induction of an RB-associated G (1) arrest via suppression of cyclin D-CDK4/6-Rb pathway. LY2157299 enhances anti-tumor effect by disrupting TGF-ß-dependent HIF-1α signaling and by activating both Smad and PI3K-AKT pathways towards transcription of S/G2 checkpoints. CONCLUSION: This study establishes the groundwork for the development of a combinatorial pharmacologic approach by using either LY2385219 or LY2157299 inhibitor plus O6-Benzylguanine to augment temozolomide response in temozolomide-resistant GB cells.

Gene regulation gravitates toward either addition or multiplication when combining the effects of two signals.

Two different cell signals often affect transcription of the same gene. In such cases, it is natural to ask how the combined transcriptional response compares to the individual responses. The most commonly used mechanistic models predict additive or multiplicative combined responses, but a systematic genome-wide evaluation of these predictions is not available. Here, we analyzed the transcriptional response of human MCF-7 cells to retinoic acid and TGF-ß, applied individually and in combination. The combined transcriptional responses of induced genes exhibited a range of behaviors, but clearly favored both additive and multiplicative outcomes. We performed paired chromatin accessibility measurements and found that increases in accessibility were largely additive. There was some association between super-additivity of accessibility and multiplicative or super-multiplicative combined transcriptional responses, while sub-additivity of accessibility associated with additive transcriptional responses. Our findings suggest that mechanistic models of combined transcriptional regulation must be able to reproduce a range of behaviors.

4-Octyl itaconate protects against renal fibrosis via inhibiting TGF-ß/Smad pathway, autophagy and reducing generation of reactive oxygen species.

Renal fibrosis is an inevitable course of all kinds of progressive chronic kidney disease (CKD). Itaconic acid is an endogenous metabolite that has shown anti-inflammatory and antioxidant effects. 4-octyl itaconate (OI), a derivative of itaconic acid with higher fat solubility, can penetrate the cell membranes and be metabolized into itaconic acid in vitro. However, whether OI has an anti-renal fibrotic effect is still unclear. The current study purposed to investigate the anti-fibrotic effect in renal and the underlying mechanisms of OI. The unilateral ureteral occlusion (UUO) model and adenine-induced fibrosis model in Sprague-Dawley (SD) rats and Transforming growth factor-ß1 (TGF-ß1) induced HK-2 cells were applied to investigate the renoprotective effects of OI. This study reports for the first time that OI ameliorated renal fibrosis by suppressing the activation of TGF-ß/Smad and nuclear factor kappa B (NF-κB) pathways, reducing generation of reactive oxygen species and inhibiting autophagy. These results clearly suggest that OI has great clinical potential for managing renal fibrosis.

Honokiol: A polyphenol neolignan ameliorates pulmonary fibrosis by inhibiting TGF-ß/Smad signaling, matrix proteins and IL-6/CD44/STAT3 axis both in vitro and in vivo.

Pulmonary fibrosis (PF) is an epithelial/fibroblastic crosstalk disorder of the lungs with highly complex etiopathogenesis. Limited treatment possibilities are responsible for poor prognosis and mean survival rate of 3 to 5 years of PF patients after definite diagnosis. Once thought to be an irreversible disorder, recent evidences have brought into existence the concept of organ fibrosis reversibility due to plastic nature of fibrotic tissues. These findings have kindled interest among the scientific community and given a new direction for research in the arena of fibrosis for developing new anti-fibrotic therapies. The current study is designed to evaluate the anti-fibrotic effects of Honokiol (HNK), a neolignan active constituent from Magnolia officinalis. This study has been conducted in TGF-ß1 induced in vitro model and 21 day in vivo murine model of Bleomycin induced PF. The findings of our study suggest that HNK was able to inhibit fundamental pathways of epithelial to mesenchymal transition (EMT) and TGF-ß/Smad signaling both in vitro and in vivo. Additionally, HNK also attenuated collagen deposition and inflammation associated with fibrosis. We also hypothesized that HNK interfered with IL-6/CD44/STAT3 axis. As hypothesized, HNK significantly mitigated IL-6/CD44/STAT3 axis both in vitro and in vivo as evident from outcomes of various protein expression studies like western blotting, immunohistochemistry and ELISA. Taken together, it can be concluded that HNK reversed pulmonary fibrotic changes in both in vitro and in vivo experimental models of PF and exerted anti-fibrotic effects majorly by attenuating EMT, TGF-ß/Smad signaling and partly by inhibiting IL-6/CD44/STAT3 signaling axis.

Aucubin exerts anti-osteoporotic effects by promoting osteoblast differentiation.

Osteoporosis is a metabolic disease characterized by reduced osteoblast differentiation and proliferation. Oxidative stress plays a role in the pathogenesis of osteoporosis. Aucubin (AU), an iridoid glycoside, was previously shown to promote osteoblast differentiation. We investigated the effects of AU on MG63 human osteoblast-like cells treated with dexamethasone (Dex) or hydrogen peroxide (H2O2) to induce oxidative damage. AU protected MG63 cells against apoptosis, and promoted increased expression of cytokines associated with osteoblast differentiation, including collagen I, osteocalcin (OCN), osteopontin (OPN), and osterix. In Dex- and H2O2-treated MG63 cells, AU also enhanced the expression of anti-oxidative stress-associated factors in the nuclear respiratory factor 2 signaling pathway, including superoxide dismutases 1 and 2, heme oxygenases 1 and 2, and catalase. In vivo, using a Dex-induced mouse model of osteoporosis, AU promoted increased cortical bone thickness, increased bone density, and tighter trabecular bone. Additionally, it stimulated an increase in the expression of collagen I, OCN, OPN, osterix, and phosphorylated Akt and Smads in bone tissue. Finally, AU stimulated the expression of cytokines associated with osteoblast differentiation in bone tissue and serum. Our data indicate AU may have therapeutic efficacy in osteoporosis.

Mechanistic aspects of antifibrotic effects of honokiol in Con A-induced liver fibrosis in rats: Emphasis on TGF-ß/SMAD/MAPK signaling pathways.

Aim Liver fibrosis represents a massive global health burden with limited therapeutic options. Thus, the need for curative options is evident. Thus, this study aimed to assess the potential antifibrotic effect of honokiol in Concanavalin A (Con A) induced immunological model of liver fibrosis as well the possible underlying molecular mechanisms. METHODS: Male Sprague-Dawley rats were treated with either Con A (20 mg/kg, IV) and/or honokiol (10 mg/kg, orally) for 4 weeks. Hepatotoxicity indices were as well as histopathological evaluation was done. Hepatic fibrosis was assessed by measuring alpha smooth muscle actin (α-SMA) expression and collagen fibers deposition by Masson's trichrome stain and hydroxyproline content. To elucidate the underlying molecular mechanisms, the effect of honokiol on oxidative stress, inflammatory markers as well as transforming growth factor beta (TGF-ß)/SMAD and mitogen-activated protein kinase (MAPK) pathways was assessed. KEY FINDINGS: Honokiol effectively reversed the hepatotoxicity indices elevations and abnormal histopathological changes induced by Con A. Besides, honokiol attenuated Con A-induced liver fibrosis by down-regulation of hydroxyproline levels, α-SMA expression together with a marked decrease in collagen fibers deposition. Mechanistically Con A induced oxidative stress, provocation of inflammatory responses and activation of TGF-ß/SMAD/MAPK pathways. Contrariwise, honokiol co-treatment significantly restored antioxidant defence mechanisms, down-regulated inflammatory cascades and inhibited TGF-ß/SMAD/MAPK signaling pathways. CONCLUSION: The results provide an evidence for the promising antifibrotic effect of honokiol that could be partially due to suppressing oxidative stress and inflammatory processes as well as inhibition of TGF-ß/SMAD/MAPK signaling pathways.

TCDD inhibited the osteogenic differentiation of human fetal palatal mesenchymal cells through AhR and BMP-2/TGF-ß/Smad signaling.

Exposure to environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes cleft palate at high rates, but little is known about the underlying biological mechanisms. In the present study, we cultured osteoblasts from human fetal palate mesenchymal cells (hFPMCs) to explore the effects of TCDD on osteogenic differentiation. The results showed that TCDD significantly decreased cell proliferation, alkaline phosphatase (ALP) activity and calcium deposition. RNA analyses and protein detection demonstrated that TCDD downregulated a wide array of pro-osteogenic biomarkers. Further investigation of the underlying molecular mechanisms revealed that exposure to TCDD activated aryl hydrocarbon receptor (AhR) signaling and inhibited BMP-2/TGF-ß1/Smad pathway molecules. The inactivation of AhR signaling using CRISPR/Cas9-mediated AhR deletion or by genetic siRNA knockdown significantly blocked the effects induced by TCDD, suggesting a critical role of AhR activation in the TCDD-mediated inhibition of hFPMC osteogenic differentiation. The cotreatment with TGF-ß1 or BMP-2 and TCDD significantly relieved the activation of AhR and rescued the impairment of osteogenesis caused by TCDD. Taken together, our findings indicated that TCDD inhibited the osteogenic differentiation of hFPMCs via crosstalk between AhR and BMP-2/TGF-ß1/Smad signaling pathway.

Salvianolic acid B exerts anti-liver fibrosis effects via inhibition of MAPK-mediated phospho-Smad2/3 at linker regions in vivo and in vitro.

AIM: To investigate anti-liver fibrosis effects of Salvianolic acid B (Sal B) from Salvia miltiorrhiza Bunge involved mitogen-activated protein kinase (MAPK)-mediated transforming growth factor-beta (TGF-ß) signaling. MAIN METHODS: Diethylnitrosamine (DEN)-induced liver fibrosis in mice and TGF-ß1-activated hepatic stellate cells (HSCs) were established and treated with dosage/concentration-graded Sal B and/or MAPK activator (Vacquinol-1: MKK4-specific activator)/inhibitors (PD98059: ERK-specific inhibitor; SP600125: JNK-specific inhibitor; SB203580: p38-specific inhibitor). Histopathological characteristics and cell migration were assessed, α-SMA, Collagen I and members of TGF-ß/MAPK/Smad signal transduction pathway were measured. KEY FINDINGS: Results in vivo showed that Sal B alleviated DEN-caused liver fibrosis embodied in ameliorative histopathological characteristics and decreased protein levels of hepatic fibrosis related markers (α-SMA, Collagen I, TGF-ß1), its molecular mechanisms of action were correlative with inhibited activation of MAPK and phosphorylation of Smad2/3 at linker regions (P-Smad2/3L) and Smad2 at C-terminal (P-Smad2C) while increased phosphorylation of Smad3 at C-terminal (P-Smad3C). Results in vitro showed that Sal B restrained TGF-ß1-induced HSCs activation, Collagen I production and cell migration; Sal B inhibited activation of MAPK and markedly decreased protein levels of P-Smad2/3L and P-Smad2C while slightly increased P-Smad3C in TGF-ß1-stimulated HSCs, the expression of PAI-1 was inhibited by Sal B; activating MAPK receded inhibitory effects of Sal B on α-SMA, Collagen I, P-Smad2L and P-Smad3L expression while inhibited activation of MAPK reinforced those. SIGNIFICANCE: Sal B attenuates liver fibrosis via mediation of TGF-ß/Smad and MAPK pathways, especially inhibition of MAPK-mediated P-Smad2/3L signaling, which maybe provides theoretical foundation of Sal B for treating clinically liver fibrosis.

[Doxycycline inhibits paraquat-induced pulmonary fibrosis via TGF-ß1/Smad pathway].

Objective: To investigate the possible mechanism of doxycycline inhibiting paraquat-induced pulmonary fibrosis and provide a theoretical basis for its clinical application. Methods: Human lung fibroblast HFL1 cells were selected as the research object in the cell group. Divided into blank group, paraquat group, paraquat+doxycycline group. The expression of TGF-ß1, a-SMA, Smad3 and Smad2 protein was detected by ELISA using 40 ml of paraquat 40 umol/L and 3 mg/L of oleic acid 10 mg/L. In the animal group, 120 healthy and clean SD rats were randomly divided into three groups: blank group, paraquat group, paraquat+doxycycline group. The expression of TGF-ß1, a-SMA, Smad3 and Smad2 protein in lung tissue of mice at 1 day, 3 days, 7 days, 14 days and 21 days was detected by Elisa method. The expression of TGF-ß1, a-SMA, Smad3 and Smad2 protein in lung tissue of 21-day mice was detected by Western Blotting. The pathological changes of lung tissue were observed by HE staining for 1 day, 3 days, 7 days, 14 days and 21 days. Results: In the cell group experiment, the expression of TGF-ß1, a-SMA, Smad3 and Smad2 protein increased gradually with paraquat in the paraquat group, and the expression of TGF-ß1, a-SMA, Smad3 and Smad2 protein was significantly higher than that in the blank group. The difference was statistically significant (P<0.05) . The expressions of TGF-ß1, a-SMA, Smad3 and Smad2 in the paraquat+doxycycline group were significantly lower than those in the paraquat group, but still higher than the blank group, the difference was statistically significant (P<0.05) . Conclusion: Doxycycline inhibits paraquat-induced pulmonary fibrosis by inhibiting the expression of TGF-ß1, a-SMA and Smad3, Smad2 proteins.

Effect of Dexamethasone on TGF-ß1/Smad3 Signalling Pathway in Airway Remodelling Model of Asthmatic Rats.

OBJECTIVE: To determine the effect of dexamethasone on regulating the TGF-ß1/Smad3 signalling pathway in airway remodelling model of asthmatic rats. STUDY DESIGN: An experimental study. PLACE AND DURATION OF STUDY: Department of Pathology, The First Hospital of Wuhan, Hubei Province, China, from February 2017 to April 2018. METHODOLOGY: Thirty male SPF Sprague-Dawley rats were randomly divided into the control group, the model group and the dexamethasone group, with 10 rats in each group. Rats were sensitised and excited by ovalbumin (OVA) to establish the model of bronchial asthma. The bronchial basement membrane perimeter (Pbm), the bronchial wall thickness (Wat), the smooth muscle thickness (Wam), collagenous fiber thickness (Wac) and other airway remodelling indices were measured and calculated by image analysis system. The expressions of TGF-ß1 and Smad3 mRNA and protein in lung tissue of each group of rats were detected by RT-PCR and Western blot. RESULTS: Wat/Pbm, Wai/Pbm and Wam/Pbm in the model group were higher compared with those in the control group (all p<0.001); Wat/Pbm, Wai/Pbm, and Wam/Pbm in the dexamethasone group were significantly lower than those in the model group (all p<0.001). Relative expression levels of TGF-ß1, Smad3 mRNA and protein in the model group were higher than those in the control group (all p<0.001); the relative expression levels of TGF-ß1, Smad3 mRNA and protein in the dexamethasone group were lower than those in the model group (all p<0.001). CONCLUSION: Dexamethasone may antagonize airway remodeling by regulating TGF-ß1/Smad3 signaling pathway, which likely to play a role in the treatment of bronchial asthma.

Bi-directional regulation of TGF-ß/Smad pathway by arsenic: A systemic review and meta-analysis of in vivo and in vitro studies.

BACKGROUND: Arsenic exposure can cause fibrosis of organs including the liver, heart and lung. It was reported that TGF-ß/Smad pathway played a crucial role in the process of fibrosis. However, the mechanism of arsenic-induced fibrosis through TGF-ß/Smad signaling pathway has remained controversial. OBJECTIVE: A systematic review and meta-analysis was performed to clarify the relationship between arsenic and TGF-ß/Smad pathway, providing a theoretical basis of fibrosis process caused by arsenic. METHODS: A meta-analysis was used to reveal a correlation between arsenic and fibrosis markers of TGF-ß/Smad pathway, including 47 articles of both in vivo and in vitro studies. (Standardized Mean Difference) SMD was employed to compare and analyze the combined effects. When I2 > was 50%, random effect model was selected and subgroup analysis was used to explore the source of heterogeneity. RESULTS: Arsenic exposure up-regulated the expression of TGF-ß1, p-Smad2/3, α-SMA, Collagen1/3 and FN. The dose-response relationship showed that low dose (≤5 µmol/L) arsenic exposure up-regulated the expression of TGF-ß1, whereas high doses had a tendency to down-regulate that of TGF-ß1. Subgroup analysis showed that low or short-term arsenic exposure induced the expression of TGF-ß1 and fibrosis markers. CONCLUSION: The results indicated that arsenic activates the TGF-ß/Smad pathway and induced fibrosis. The mechanism is related to the up-regulation of NADPH oxidase and ROS accumulation. However, high-dose arsenic exposure may inhibit this pathway.

Oridonin Inhibits Myofibroblast Differentiation and Bleomycin-induced Pulmonary Fibrosis by Regulating Transforming Growth Factor ß (TGFß)/Smad Pathway.

BACKGROUND Idiopathic pulmonary fibrosis (IPF) is a progressive disease with unknow. etiology and a high mortality rate. Oridonin is a diterpenoid isolated from the Rabdosia rubesecens with diverse biological functions. However, whether oridonin possess potential protective activity on IPF is still unclear. MATERIAL AND METHODS The aim of the present study was to explore the therapeutic effects of oridonin on IPF. First, TGF-ß1-induced MRC-5 cells were employed for the evaluation of inhibitory activity in vitro. Then, a bleomycin (BLM)-induced mice pulmonary fibrosis model was used to verify the activity of oridonin in vivo. Several pathological changes, including alveolar space collapse, emphysema, and infiltration of inflammatory cells, were observed in the BLM­treated mice. RESULTS Oridonin could significantly inhibit the mRNA and protein expression levels of α-SMA and COL1A1 in TGF-ß1-induced MRC-5 cells. Oridonin could attenuate pathological changes, including alveolar space collapse, emphysema, and infiltration of inflammatory cells induced by BLM. In addition, oridonin could significantly inhibit BLM-induced upregulation of α-SMA and COL1A1 and the phosphorylation of Smad2/3 in lung tissues of mice. CONCLUSIONS Oridonin could be used as a potential therapeutic agent in treatment for patients with IPF. The mechanisms of anti-fibrosis effect of oridonin might be inhibition of the TGF-ß/Smad pathway.