SULF1 expression is increased and promotes fibrosis through the TGF-ß1/SMAD pathway in idiopathic pulmonary fibrosis.

BACKGROUND: Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease of unknown etiology. Despite the increasing global incidence and poor prognosis, the exact pathogenic mechanisms remain elusive. Currently, effective therapeutic targets and treatment methods for this disease are still lacking. This study tried to explore the pathogenic mechanisms of IPF. We found elevated expression of SULF1 in lung tissues of IPF patients compared to normal control lung tissues. SULF1 is an enzyme that modifies heparan sulfate chains of heparan sulfate proteoglycans, playing a critical role in biological regulation. However, the effect of SULF1 in pulmonary fibrosis remains incompletely understood. Our study aimed to investigate the impact and mechanisms of SULF1 in fibrosis. METHODS: We collected lung specimens from IPF patients for transcriptome sequencing. Validation of SULF1 expression in IPF patients was performed using Western blotting and RT-qPCR on lung tissues. ELISA experiments were employed to detect SULF1 concentrations in IPF patient plasma and TGF-ß1 levels in cell culture supernatants. We used lentiviral delivery of SULF1 shRNA to knock down SULF1 in HFL1 cells, evaluating its effects on fibroblast secretion, activation, proliferation, migration, and invasion capabilities. Furthermore, we employed Co-Immunoprecipitation (Co-IP) to investigate the regulatory mechanisms involved. RESULTS: Through bioinformatic analysis of IPF transcriptomic sequencing data (HTIPF) and datasets GSE24206, and GSE53845, we identified SULF1 may potentially play a crucial role in IPF. Subsequently, we verified that SULF1 was upregulated in IPF and predominantly increased in fibroblasts. Furthermore, SULF1 expression was induced in HFL1 cells following exposure to TGF-ß1. Knockdown of SULF1 suppressed fibroblast secretion, activation, proliferation, migration, and invasion under both TGF-ß1-driven and non-TGF-ß1-driven conditions. We found that SULF1 catalyzes the release of TGF-ß1 bound to TGFßRIII, thereby activating the TGF-ß1/SMAD pathway to promote fibrosis. Additionally, TGF-ß1 induces SULF1 expression through the TGF-ß1/SMAD pathway, suggesting a potential positive feedback loop between SULF1 and the TGF-ß1/SMAD pathway. CONCLUSIONS: Our findings reveal that SULF1 promotes fibrosis through the TGF-ß1/SMAD pathway in pulmonary fibrosis. Targeting SULF1 may offer a promising therapeutic strategy against IPF.

CD9 promotes TßR2-TßR1 association driving the transition of human dermal fibroblasts to myofibroblast under hypoxia.

BACKGROUND: During wound healing, fibroblast to myofibroblast transition is required for wound contraction and remodeling. While hypoxia is an important biophysical factor in wound microenvironment, the exact regulatory mechanism underlying hypoxia and fibroblast-to-myofibroblast transition remains unclear. We previously found that tetraspanin CD9 plays an important role in oxygen sensing and wound healing. Herein, we investigated the effects of physiological hypoxia on fibroblast-to-myofibroblast transition and the biological function and mechanism of CD9 in it. METHODS: Human skin fibroblasts (HSF) and mouse dermis wounds model were established under physiological hypoxia (2% O2). The cell viability and contractility of HSF under hypoxia were evaluated by CCK8 and collagen gel retraction, respectively. The expression and distribution of fibroblast-to-myofibroblast transition markers and CD9 in HSF were detected by Western blotting and immunofluorescence. CD9 slicing and overexpressing HSFs were constructed to determine the role of CD9 by small interfering RNA and recombinant adenovirus vector. The association of TßR2 and TßR1 was measured by immunoprecipitation to explore the regulatory mechanism. Additionally, further validation was conducted on mouse dermis wounds model through histological analysis. RESULTS: Enhanced fibroblast-to-myofibroblast transition and upregulated CD9 expression was observed under hypoxia in vitro and in vivo. Besides, reversal of fibroblast-to-myofibroblast transition under hypoxia was observed when silencing CD9, suggesting that CD9 played a key role in this hypoxia-induced transition. Moreover, hypoxia increased fibroblast-to-myofibroblast transition by activating TGF-ß1/Smad2/3 signaling, especially increased interaction of TßR2 and TßR1. Ultimately, CD9 was determined to directly affect TßR1-TßR2 association in hypoxic fibroblast. CONCLUSION: Collectively, these findings suggest that CD9 promotes TßR2-TßR1 association, thus driving the transition of human dermal fibroblasts to myofibroblast under hypoxia.

Experimental study on H2O2 activation of HSC-T6 and hepatic fibrosis in cholestatic mice by "Yajieshaba".

ETHNOPHARMACOLOGICAL RELEVANCE: Yajieshaba (YJSB), approved by the Yunnan Provincial Food and Drug Administration in 2008, are known for their anti-inflammatory, antiviral, and pro-apoptotic properties, effectively treating Hepatic fibrosis (HF). However, its mechanism of action remains unclear. AIM OF THE STUDY: The objective of this investigation is to explore how YJSB influences the TGF-ß1/Smad signaling pathway as a strategy for reducing HF. METHODS: The establishment of a HF model in mice involved ligation of the common bile duct, followed by administration of YJSB. Body and liver weights were measured, and the liver index calculated. Serum levels of ALT, AST, ALP, TBA, and TBIL were assessed using colorimetric methods. Additionally, liver homogenates were analyzed for PIIINP, Col-IV, LN, HA, and Hyp, as well as TGF-ß1 activity, using ELISA. Histological analyses of liver sections, stained with H&E, Ag, and Masson's trichrome, were performed to examine inflammation and the accumulation of collagen and reticular fibers. These studies aimed to elucidate the pharmacodynamic effects of YJSB on HF in mice with bile duct obstruction. The target pathways of YJSB were preliminarily identified through immunofluorescence detection of TGF-ß1, P-Smad2L, P-Smad2C, P-Smad3L, P-Smad3C, and Smad4 proteins. In vitro experiments included the induction of hepatic stellate cell (HSC-T6) activation by H2O2. A cell injury model was established for HSC-T6, and the CCK-8 assay was used to determine the optimal YJSB concentration and treatment duration. After pirfenidone (PFD) administration, which inhibits the TGF-ß1/Smad pathway, the effects of YJSB on HSC-T6 cell proliferation were observed. ELISA assays quantified Col-III, α-SMA, and Col-I in cell lysates to assess YJSB's impact on collagen synthesis in HSC-T6 cells. Western blot analysis was performed to assess the protein levels within the TGF-ß1/Smad signaling cascade. RESULTS: In the HF mouse model, administration of YJSB notably augmented the body weight and reduced the liver index. Concurrently, there was an elevation in serum concentrations of ALP, AST, ALT, TBA, and TBIL. Similarly, in the liver homogenates of HF mice, increases were observed in the levels of HA, PIIINP, Col-IV, LN, Hyp, and TGF-ß1. Histological assessments using H&E, Ag, and Masson stains indicated a substantial diminution in liver tissue damage. Through immunofluorescence analysis, it was discerned that YJSB modulated the expression of TGF-ß1, P-Smad2L, P-Smad2C, and P-Smad3L downwards, while elevating P-Smad3C and Smad4 protein expressions. Additional investigations revealed a significant reduction in α-SMA, Col-I, and Col-III levels in cell culture fluids, suggesting a decrease in collagen synthesis and a protective role against cellular damage. Western blot analyses demonstrated that the TGF-ß1/Smad pathway inhibitor, PFD, acted in synergy with YJSB, enhancing its regulatory effects on this pathway, decreasing levels of TGF-ß1, P-Smad2L, P-Smad2C, P-Smad3L, and promoting the expression of P-Smad3C. CONCLUSIONS: YJSB demonstrates a pharmacodynamic effect against HF, enhancing liver functionality and effectively mitigating the damage associated with bile duct obstruction. The proposed action mechanism of YJSB involves modulation of the TGF-ß1/Smad signaling pathway. Research indicates that YJSB might play a role in suppressing the movement, programmed cell death, and activation of HSC-T6, potentially decelerating the advancement of hepatic fibrosis.

TGFß1, SMAD and ß-catenin in pulmonary arteries of smokers, patients with small airway disease and COPD: potential drivers of EndMT.

We previously reported pulmonary arterial remodelling and active endothelial-to-mesenchymal transition (EndMT) in smokers and patients with early chronic obstructive pulmonary disease (COPD). In the present study, we aimed to evaluate the role of different drivers of EndMT. Immunohistochemical staining for EndMT drivers, TGF-ß1, pSMAD-2/3, SMAD-7, and ß-catenin, was performed on lung resections from 46 subjects. Twelve were non-smoker-controls (NC), six normal lung function smokers (NLFS), nine patients with small-airway diseases (SAD), nine mild-moderate COPD-current smokers (COPD-CS) and ten COPD-ex-smokers (COPD-ES). Histopathological measurements were done using Image ProPlus softwarev7.0. We observed lower levels of total TGF-ß1 (P<0.05) in all smoking groups than in the non-smoking control (NC). Across arterial sizes, smoking groups exhibited significantly higher (P<0.05) total and individual layer pSMAD-2/3 and SMAD-7 than in the NC group. The ratio of SAMD-7 to pSMAD-2/3 was higher in COPD patients compared with NC. Total ß-catenin expression was significantly higher in smoking groups across arterial sizes (P<0.05), except for COPD-ES and NLFS groups in small and medium arteries, respectively. Increased total ß-catenin was positively correlated with total S100A4 in small and medium arteries (r = 0.35, 0.50; P=0.02, 0.01, respectively), with Vimentin in medium arteries (r = 0.42, P=0.07), and with arterial thickness of medium and large arteries (r = 0.34, 0.41, P=0.02, 0.01, respectively). This is the first study uncovering active endothelial SMAD pathway independent of TGF-ß1 in smokers, SAD, and COPD patients. Increased expression of ß-catenin indicates its potential interaction with SMAD pathway, warranting further research to identify the deviation of this classical pathway.

Intrauterine infusion of platelet-rich plasma improves fibrosis by transforming growth factor beta 1/Smad pathway in a rat intrauterine adhesion model.

This study aims to elucidate the effects of Platelet-rich plasma (PRP) in fibrosis development in intrauterine adhesion (IUA), and the associated underlying mechanisms are also explored, which are expected to be a potential therapeutic scheme for IUA. In this research, PRP was obtained and prepared from the peripheral venous blood of rats. A rat model was induced by mechanical injury. Further, PRP was directly injected into the uterus for treatment. The appearance and shape of the uterus were assessed based on the tissues harvested. The fibrosis biomarker levels were analyzed. The transforming growth factor beta 1 (TGF-ß1) and Mothers against decapentaplegic homolog 7 (Smad7) levels, the phosphorylation of Smad2 (p-Smad2), and the phosphorylation of Smad3 (p-Smad3) were analyzed, and the molecular mechanism was investigated by rescue experiments. It was found that PRP improved the appearance and shape of the uterus in IUA and increased endometrial thickness and gland numbers. The administration of PRP resulted in a decrease in the expressions of fibrosis markers including collagen I, α-SMA, and fibronectin. Furthermore, PRP increased Smad7 levels and decreased TGF-ß1 levels, p-Smad2, and p-Smad3. Meanwhile, administration of TGF-ß1 activator reversed the therapeutic effects of PRP in IUA. Collectively, the intrauterine infusion of PRP can promote endometrial damage recovery and improve endometrial fibrosis via the TGF-ß1/Smad pathway. Hence, PRP can be a potential therapeutic strategy for IUA.

Protective Effect of Black Rice Cyanidin-3-Glucoside on Testicular Damage in STZ-Induced Type 1 Diabetic Rats.

Diabetic testicular damage is quite a common and significant complication in diabetic men, which could result in infertility. The natural fertility rate of type 1 diabetes men is only 50% because of testicular damage. This research first aimed to explore the intervention effect of C3G on testicular tissue damage induced by diabetes. Here, a streptozotocin-induced type 1 diabetic rat model was established, and then C3G was administered. After 8 weeks of C3G supplementation, the symptoms of diabetes (e.g., high blood glucose, lower body weight, polydipsia, polyphagia) were relieved, and at the same time that sperm motility and viability increased, sperm abnormality decreased in C3G-treated diabetic rats. Furthermore, the pathological structure of testis was restored; the fibrosis of the testicular interstitial tissue was inhibited; and the LH, FSH, and testosterone levels were all increased in the C3G-treated groups. Testicular oxidative stress was relieved; serum and testicular inflammatory cytokines levels were significantly decreased in C3G-treated groups; levels of Bax, Caspase-3, TGF-ß1 and Smad2/3 protein in testis decreased; and the level of Bcl-2 was up-regulated in the C3G-treated groups. A possible mechanism might be that C3G improved antioxidant capacity, relieved oxidative stress, increased anti-inflammatory cytokine expression, and inhibited the apoptosis of spermatogenic cells and testicular fibrosis, thus promoting the production of testosterone and repair of testicular function. In conclusion, this study is the first to reveal that testicular damage could be mitigated by C3G in type 1 diabetic rats. Our results provide a theoretical basis for the application of C3G in male reproductive injury caused by diabetes.

Compound collagen peptide powder improves skin photoaging by reducing oxidative stress and activating TGF-ß1/Smad pathway.

Fish collagen peptide (FCP) has been extensively investigated as a natural product that can combat photoaging; however, its efficacy is limited by its singular composition. Compound collagen peptide powder (CCPP) is a novel functional food formulation that exhibits photoprotective properties and comprises FCP and a blend of natural botanical ingredients. The objective of this study was to investigate the efficacy of CCPP and its molecular mechanism. CCPP had a low molecular weight, facilitating its efficient absorption, and was abundant in amino acids, total polyphenols, and total flavonoids. The results of in vivo studies demonstrated that CCPP exhibited significant efficacy in reducing skin wrinkles, enhancing the contents of water and oil in the skin, and ameliorating histopathological alterations in mice. The results of in vitro studies demonstrated that CCPP effectively mitigated photoaging in human skin fibroblasts by attenuating oxidative stress and promoting extracellular matrix (ECM) synthesis. Moreover, we clearly demonstrated that the TGF ß1/Smad pathway was involved in the promotion of ECM synthesis and cell proliferation by CCPP in human skin fibroblasts. These findings suggest that, compared with single collagen, CCPP has a more comprehensive range of antiphotoaging properties.

A novel electrospun polylactic acid silkworm fibroin mesh for abdominal wall hernia repair.

Objective: Abdominal wall hernias are common abdominal diseases, and effective hernia repair is challenging. In clinical practice, synthetic meshes are widely applied for repairing abdominal wall hernias. However, postoperative complications, such as inflammation and adhesion, are prevalent. Although biological meshes can solve this problem to a certain extent, they face the problems of heterogeneity, rapid degradation rate, ordinary mechanical properties, and high-cost. Here, a novel electrospinning mesh composed of polylactic acid and silk fibroin (PLA-SF) for repairing abdominal wall hernias was manufactured with good physical properties, biocompatibility and low production cost. Materials and methods: FTIR and EDS were used to demonstrate that the PLA-SF mesh was successfully synthesized. The physicochemical properties of PLA-SF were detected by swelling experiments and in vitro degradation experiments. The water contact angle reflected the hydrophilicity, and the stress‒strain curve reflected the mechanical properties. A rat abdominal wall hernia model was established to observe degradation, adhesion, and inflammation in vivo. In vitro cell mesh culture experiments were used to detect cytocompatibility and search for affected biochemical pathways. Results: The PLA-SF mesh was successfully synthesized and did not swell or degrade over time in vitro. It had a high hydrophilicity and strength. The PLA-SF mesh significantly reduced abdominal inflammation and inhibited adhesion formation in rat models. The in vitro degradation rate of the PLA-SF mesh was slower than that of tissue remodeling. Coculture experiments suggested that the PLA-SF mesh reduced the expression of inflammatory factors secreted by fibroblasts and promoted fibroblast proliferation through the TGF-ß1/Smad pathway. Conclusion: The PLA-SF mesh had excellent physicochemical properties and biocompatibility, promoted hernia repair of the rat abdominal wall, and reduced postoperative inflammation and adhesion. It is a promising mesh and has potential for clinical application.

Periplaneta americana extract attenuates hepatic fibrosis progression by inhibiting collagen synthesis and regulating the TGF-ß1/Smad signaling pathway.

INTRODUCTION: Liver fibrosis is the damage repair response following chronic liver diseases. Activated hepatic stellate cells (HSCs) are the main extracellular matrix (ECM)-producing cells and key regulators in liver fibrosis. Periplaneta americana shows prominent antifibrotic effects in liver fibrosis; however, the underlying mechanisms remain undetermined. This study aimed to elucidate the therapeutic effects of P. americana extract (PA-B) on liver fibrosis based on the regulation of the TGF-ß1/Smad signal pathway. MATERIAL AND METHODS: HSCs and Sprague Dawley rats were treated with TGF-ß1 and CCl4, respectively, to establish the hepatic fibrosis model in vitro and in vivo. The effect of PA-B on liver rat fibrosis was evaluated by biochemical (serum aspartate aminotransferase (AST), alanine aminotransferase (ALT), hyaluronic acid (HA), laminin (LN), collagen type IV (Col-IV), pro-collagen type III (PC-III)) and histological examinations. Further, fibrogenic markers expression of alpha smooth muscle actin (α-SMA), collagen type I (Col-I), and collagen type III (Col-III), and the TGF-ß1/Smad pathway-related factors were assessed by immunofluorescence (IF), real time quantitative polymerase chain reaction (RT-qPCR), and western blotting (WB). RESULTS: Treatment of HSC-T6 cells with PA-B suppressed the expression of α-SMA, Col-I, and Col-III, downregulated the expression of TGF-ß1 receptors I and II (TßR I and TßR II, respectively), Smad2, and Smad3, and upregulated Smad7 expression. PA-B mitigates pathologic changes in the rat model of liver fibrosis, thus alleviating liver index, and improving liver function and fibrosis indices. The effects of PA-B on the expression of α-SMA, Col-I, Col-III, TßR I, TßR II, Smad2, Smad3, and Smad7 were consistent with the in vitro results, including reduced TGF-ß1 expression. CONCLUSIONS: The therapeutic effect of PA-B on liver fibrosis might involve suppression of the secretion and expression of TGF-ß1, regulation of the TGF-ß1/Smad signaling pathway, and inhibition of collagen production and secretion.

Chromium Picolinate Protects against Testicular Damage in STZ-Induced Diabetic Rats via Anti-Inflammation, Anti-Oxidation, Inhibiting Apoptosis, and Regulating the TGF-ß1/Smad Pathway.

Chromium picolinate (CP) is an organic compound that has long been used to treat diabetes. Our previous studies found CP could relieve diabetic nephropathy. Thus, we speculate that it might have a positive effect on diabetic testicular injury. In this study, a diabetic rat model was established, and then the rats were treated with CP for 8 weeks. We found that the levels of blood glucose, food, and water intake were reduced, and body weight was enhanced in diabetic rats after CP supplementation. Meanwhile, in CP treatment groups, the levels of male hormone and sperm parameters were improved, the pathological structure of the testicular tissue was repaired, and testicular fibrosis was inhibited. In addition, CP reduced the levels of serum inflammatory cytokines, and decreased oxidative stress and apoptosis in the testicular tissue. In conclusion, CP could ameliorate testicular damage in diabetic rats, as well as being a potential testicle-protective nutrient in the future to prevent the testicular damage caused by diabetes.

Fluorofenidone alleviates liver fibrosis by inhibiting hepatic stellate cell autophagy via the TGF-ß1/Smad pathway: implications for liver cancer.

Objectives: Liver fibrosis is a key stage in the progression of various chronic liver diseases to cirrhosis and liver cancer, but at present, there is no effective treatment. This study investigated the therapeutic effect of the new antifibrotic drug fluorofenidone (AKF-PD) on liver fibrosis and its related mechanism, providing implications for liver cancer. Materials and Methods: The effects of AKF-PD on hepatic stellate cell (HSC) autophagy and extracellular matrix (ECM) expression were assessed in a carbon tetrachloride (CCl4)-induced rat liver fibrosis model. In vitro, HSC-T6 cells were transfected with Smad2 and Smad3 overexpression plasmids and treated with AKF-PD. The viability and number of autophagosomes in HSC-T6 cells were examined. The protein expression levels of Beclin-1, LC3 and P62 were examined by Western blotting. The Cancer Genome Atlas (TCGA) database was used for comprehensively analyzing the prognostic values of SMAD2 and SMAD3 in liver cancer. The correlation between SMAD2, SMAD3, and autophagy-related scores in liver cancer was explored. The drug prediction of autophagy-related scores in liver cancer was explored. Results: AKF-PD attenuated liver injury and ECM deposition in the CCl4-induced liver fibrosis model. In vitro, the viability and number of autophagosomes in HSCs were reduced significantly by AKF-PD treatment. Meanwhile, the protein expression of FN, α-SMA, collagen III, Beclin-1 and LC3 was increased, and P62 was reduced by the overexpression of Smad2 and Smad3; however, AKF-PD reversed these effects. SMAD2 and SMAD3 were hazardous factors in liver cancer. SMAD2 and SMAD3 correlated with autophagy-related scores in liver cancer. Autophagy-related scores could predict drug response in liver cancer. Conclusions: AKF-PD alleviates liver fibrosis by inhibiting HSC autophagy via the transforming growth factor (TGF)-ß1/Smadpathway. Our study provided some implications about how liver fibrosis was connected with liver cancer by SMAD2/SMAD3 and autophagy.

Low intensity pulsed ultrasound ameliorates Adriamycin-induced chronic renal injury by inhibiting ferroptosis.

OBJECTIVE: It is very important to develop a new therapeutic strategy to cope with the increasing morbidity and mortality of chronic kidney disease (CKD). As a kind of physical therapy, low intensity pulsed ultrasound (LIPUS) has remarkable anti-inflammatory and repair-promoting effects and is expected to become a new therapeutic method for CKD. This study aims to clarify the treatment effect of LIPUS on CKD-related renal inflammation and fibrosis, and to further explore the potential signal network of LIPUS treatment for ameliorating chronic renal injury. METHODS: A rat model simulating the progress of CKD was established by twice tail-vein injection of Adriamycin (ADR). Under anesthesia, bilateral kidneys of CKD rats were continuously stimulated by LIPUS for four weeks. The parameters of LIPUS were 1.0 MHz, 60 mW/cm2, 50% duty cycle and 20 min/d. RESULTS: LIPUS treatment effectively inhibited ADR-induced renal inflammation and fibrosis, and improved CKD-related to oxidative stress and ferroptosis. In addition, the therapeutic effect of LIPUS is closely related to the regulation of TGF-ß1/Smad and Nrf2/keap1/HO-1 signalling pathways. DISCUSSION: This study provides a new direction for further mechanism research and lays an important foundation for clinical trials.

Combined Inhibition of the TGF-ß1/Smad Pathway by Prevotella copri and Lactobacillus murinus to Reduce Inflammation and Fibrosis in Primary Sclerosing Cholangitis.

Primary sclerosing cholangitis (PSC) is a chronic cholestatic disease characterized by inflammation and fibrosis of the bile ducts. Cholestasis may lead to hepatic inflammation and fibrosis, and amelioration of cholestasis may allow recovery from inflammatory and fibrotic pathological damage. Prevotella copri (P. copri) interventions have been reported to significantly improve cholestasis and liver fibrosis in 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced PSC mouse models. Even though P. copri treatment alone cannot bring about recovery from DDC-induced inflammation, it increases the abundance of Lactobacillus murinus (L. murinus) compared with DDC treatment, which has been reported to have anti-inflammatory effects. The abundance of L. murinus still not recovering to a normal level may underlie hepatic inflammation in P. copri + DDC mice. Separate or combined interventions of P. copri and L. murinus were used to investigate the molecular mechanism underlying the improvement in PSC inflammation and fibrosis. P. copri and L. murinus significantly reduced the hepatic inflammatory cell aggregation and inflammatory factor expression as well as the hepatic collagen content and fibrin factor expression in the PSC mice. Further analysis of phosphorylation and dephosphorylation levels revealed that treating the PSC mice with the P. copri and L. murinus combined intervention inhibited the activity of the DDC-activated TGF-ß1/Smad pathway, thereby reducing liver inflammation and fibrosis. The combination of P. copri and L. murinus inhibits the TGF-ß1/Smad pathway and reduces inflammation and fibrosis in PSC.

Human-Induced Hepatocytes-Derived Extracellular Vesicles Ameliorated Liver Fibrosis in Mice Via Suppression of TGF-ß1/Smad Signaling and Activation of Nrf2/HO-1 Signaling.

Liver fibrosis is a wound-healing response caused by persistent liver injury and often occurs in chronic liver diseases. Effective treatments for liver fibrosis are still pending. Recent studies have revealed that extracellular vesicles (EVs) derived from primary hepatocytes (Hep-EVs) have therapeutic potential for multiple liver diseases. However, Hep-EVs are difficult to manufacture in bulk because of the limited sources of primary hepatocytes. Human-induced hepatocytes (hiHep) are hepatocyte-like cells that can expand in vitro, and their cell culture supernatant is thus an almost unlimited resource for EVs. This study aimed to investigate the potential therapeutic effects of EVs derived from hiHeps. hiHep-EVs inhibited the expression of inflammatory genes and the secretion of inflammation-related cytokines, and suppressed the activation of hepatic stellate cells by inhibiting the transforming growth factor (TGF)-ß1/Smad signaling pathway. The anti-inflammatory and antifibrotic effects of hiHep-EVs were similar to those of mesenchymal stem cell-EVs. Furthermore, the administration of hiHep-EVs ameliorated oxidative stress, inflammation, and fibrosis in a CCl4-induced liver fibrosis mouse model. The expression of α smooth muscle actin, collagen I, and collagen III was reduced, which may be attributed to the regulation of matrix metalloproteinase (MMP)-9, tissue inhibitor of metalloproteinases (TIMP)-1, and TIMP-2 by hiHep-EVs, and the protein expression of Nrf2, HO-1, and NQO1 was increased. Taken together, our results suggested that hiHep-EVs alleviated liver fibrosis by activating the Nrf2/HO-1 signaling pathway and inhibiting the TGF-ß1/Smad signaling pathway. This study revealed the hepatoprotective effect of hiHep-EVs, and provided a new approach to treating liver fibrosis.

ADAM17 Aggravates the Inflammatory Response by Modulating Microglia Polarization Through the TGF-ß1/Smad Pathway Following Experimental Traumatic Brain Injury.

Microglia-mediated neuroinflammatory responses play important roles in secondary neurological injury after traumatic brain injury (TBI). The TGF-ß pathway participates in the regulation of M1/M2 phenotype transformation of microglia. TGF-ß can activate the Smad pathway by binding to TGF-ßRs, which is regulated by the cleavage function of A disintegrin and metalloproteinase 17 (ADAM17). However, the role of ADAM17 and the associated signaling pathways in the pathological process after TBI remain unclear. Herein, we assessed the transformation of microglia M1/M2 phenotype polarization and the neuroinflammatory response after the inhibition of ADAM17. The formation of TGF-ßRs and TGF-ß1/TGF-ßRII complexes on microglia were detected to evaluate the effect of ADAM17 inhibition on the TGF-ß1/Smad pathway. ADAM17 was highly expressed after TBI and mainly located in the microglia. the inhibition of ADAM17 improved neurological function after TBI. The neuroprotective effect of ADAM17 inhibition was related to a shift from the M1 microglial phenotype to the M2 microglial phenotype, thus reducing TBI-induced neuroinflammation. ADAM17 inhibition increased expression of TGF-ßRs on the microglia membrane, promoted formation of TGF-ß1/TGF-ßRII complexes, and induced intranuclear translocation of Smads, which activated the TGF-ß/Smad pathway. In conclusion, our study suggested that ADAM17 inhibition regulated microglia M1/M2 phenotype polarization through the TGF-ß1/Smad pathway and influenced the neuroinflammatory response after TBI.

Levistolide A ameliorates fibrosis in chronic kidney disease via modulating multitarget actions in vitro and in vivo.

AIMS: The increasing incidence of chronic kidney disease (CKD) urgently calls for effective nephroprotective agents. Traditional Chinese Medicine Angelica sinensis and its formula are well known for CKD therapy, but the underlying mechanisms and effective substances of reno-protective effects remain unclear. To this end, we isolated eleven ligustilide dimers (1-11) from A. sinensis and examined the molecular mechanism of their nephroprotective effects. MAIN METHODS: Because of internal RAS playing an important role in CKD, we used renin expression as a target and screened preliminarily for antifibrotic effects of ligustilide dimers (1-11) by constructing a dual luciferase reporter gene in vitro. Furthermore, the reno-protective effects of the ligustilides and their underlying mechanism were investigated in TGF-ß1-stimulated HK-2 cells and 5/6 nephrectomy (Nx) mice. KEY FINDINGS: The ligustilide dimers exhibited anti-fibrotic effects by inhibiting human renin (hREN) promoter activity to decrease renin expression and down-regulate the expression of fibrosis-related factors, including α-SMA, collagen I, and fibronectin in vitro. Levistolide A (LA) and angeolide keto ester (AK) were screened out to identify their ability and underlying mechanism for treating CKD. Experimental validation further indicated that LA or AK treatment inhibited the expression of key molecules in RAS, TGF-ß1/Smad, and MAPK pathways to downregulate ECM deposition. Furthermore, LA obviously meliorated renal injury in 5/6 Nx mice through ameliorating oxidant stress, inflammation, apoptosis and renal fibrosis. SIGNIFICANCE: The experimental results demonstrated that ligustilide dimers were potential nephroprotective agents. LA might be an attractive drug candidate for renin-targeted CKD therapy.

Inhibition of TGFß1/Smad pathway by NF-κB induces inflammation leading to poor wound healing in high glucose.

This study mainly analyzed the relationship between nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and transforming growth factor-ß (TGFß1)/Smad under high glucose environment and its influence on wound healing. Fibroblast NIH-3T3 was used to analyze the effect of high concentration glucose (20 nmol/mL) on cell viability, migration ability, inflammation level and NF-κB pathway. Pyrrolidinedithiocarbamate (PDTC) was used to inhibit NF-κB for rescue experiments. Diabetic mice were used to construct wound healing models. Recombinant TGF-ß1 was used to promote wound healing in diabetic mice. FSL-1 was applied to activate NF-κB to verify the mechanism. High glucose inhibited cell viability and migration ability, promoted the expression of TNF-α, IL-6 and IL-1ß, induced the activation of NF-κB pathway in fibroblasts. Inhibition of NF-κB not only blocked the decrease in cell viability and migration ability induced by high glucose, but also relieved the release of inflammatory factors. TGF-ß1 activated the TGF-ß1/Smad pathway and promoted wound healing in diabetic mice. Activating the NF-κB pathway not only inhibited the activation of the TGF-ß1/Smad pathway, but also alleviated the promoting effect of TGF-ß1 on wound healing. In a high glucose environment, the activation of NF-κB may inhibit the function of fibroblasts by inhibiting the TGF-ß1/Smad pathway, resulting in poor wound healing.

Asiaticoside delays senescence and attenuate generation of ROS in UV­exposure cells through regulates TGF­ß1/Smad pathway.

Asiaticoside, isolated from Centella asiatica, shows great improvement on wound healing and anti-oxidation function in vitro and in vivo. From previous research, asiaticoside possesses the potential capability to delay skin aging and reduce wrinkles clinically, but its underlying mechanism to regulate aging have not well-investigated. The present study found that asiaticoside could improve the viability and maintains a normal morphology in ultraviolet (UV)-exposure cells. In addition, ß-galactosidase release was inhibited by treatment of asiaticoside in UV damaged cells was observed. The present study confirmed that UV-induced ROS generation and SOD reduction could be attenuated by incubation of asiaticoside. By using RNA sequencing technology, differential genes between UV and asiaticoside treatment were demonstrated and enriched genes suggested that asiaticoside is able to negatively regulate cell cycle and MAPK pathways. Western blotting was employed to clarify the variation of key proteins in TGF-ß1/Smad pathway and cell cycle and the result implied that asiaticoside is capable of attenuating upregulation of TGF-ß1, Smad2 and Smad3 to reverse cell senescence. The present study investigated regulation of asiaticoside to TGF-ß1/Smad pathway in UV-induced HaCat cells, showing its potential to against photoaging.

Mangiferin prevents hepatocyte epithelial-mesenchymal transition in liver fibrosis via targeting HSP27-mediated JAK2/STAT3 and TGF-ß1/Smad pathway.

Hepatocytes has been confirmed to undergo EMT and can be converted into myofibroblasts during hepatic fibrogenesis. However, the mechanism of hepatocyte EMT regulation in hepatic fibrosis, particularly through HSP27 (human homologue of rodent HSP25), remains unclear. Mangiferin (MAN), a compound extracted from Mangifera indica L, has been reported to attenuate liver injury. This study aimed to investigate the mechanisms underlying HSP27 inhibition and the anti-fibrotic effect of MAN in liver fibrosis. Our results revealed that the expression of HSP27 was remarkably increased in the liver tissues of patients with liver cirrhosis and CCl4 -induced fibrotic rats. However, HSP27 shRNA treatment significantly alleviated fibrosis. Furthermore, MAN was found to inhibit CCl4 - and TGF-ß1-induced liver fibrosis and reduced hepatocyte EMT. More importantly, MAN decreased HSP27 expression to suppress the JAK2/STAT3 pathway, and subsequently blocked TGF-ß1/Smad signaling, which were consistent with its protection against CCl4 -induced EMT and liver fibrosis. Together, these results suggest that HSP27 may play a crucial role in hepatocyte EMT and liver fibrosis by activating JAK2/STAT3 signaling and TGF-ß1/Smad pathway. The suppression of HSP27 expression by MAN may be a novel strategy for attenuating the hepatocyte EMT in liver fibrosis.

Transmembrane protein 88 inhibits transforming growth factor-ß1-induced-extracellular matrix accumulation and epithelial-mesenchymal transition program in human pleural mesothelial cells through modulating TGF-ß1/Smad pathway.

Pleural fibrosis is an irreversible pathological process occurred in the development of several lung diseases. TMEM88 is a member of transmembrane (TMEM) family and has been found to be involved in the regulation of fibrogenesis. However, the role of TMEM88 in pleural fibrosis remains unknown. In this study, we aimed to explore the role of TMEM88 in pleural fibrosis in vitro using transforming growth factor-ß1 (TGF-ß1)-induced human pleural mesothelial cell line MeT-5A cells. Our results showed that the expression levels of TMEM88 were downregulated in pleural fibrosis tissues and TGF-ß1-treated Met-5A cells. Overexpression of TMEM88 inhibited the proliferation of Met-5A cells under TGF-ß1 stimulation. In addition, TMEM88 overexpression prevented TGF-ß1-induced extracellular matrix (ECM) accumulation and epithelial-mesenchymal transition (EMT) in Met-5A cells with decreased expression levels of Col I and fibronectin, increased levels of cytokeratin-8 and E-cadherin, as well as decreased levels of vimentin and α-SMA. Furthermore, overexpression of TMEM88 inhibited the expression of TGF-ß receptor I (TßRI) and TßRII and suppressed the phosphorylation of Smad2 and Smad3 in Met-5A cells. In conclusion, these results indicated that TMEM88 exhibited an anti-fibrotic activity in pleural fibrosis via inhibiting the activation of TGF-ß1/Smad signaling pathway.