Organ Fibrosis and Autoimmunity: The Role of Inflammation in TGFβ-Dependent EMT

TGF-β: elusive target in diabetic kidney disease

Transforming growth factor-beta (TGF-β), a cytokine with near omnipresence, is an integral part of many vital cellular processes across the human body. The family includes three isoforms: Transforming growth factor-beta 1, 2, and 3. These cytokines play a significant role in the fibrosis cascade. Diabetic kidney disease (DKD), a major complication of diabetes, is increasing in prevalence daily, and the classical diagnosis of diabetes is based on the presence of albuminuria. The occurrence of nonalbuminuric DKD has provided new insight into the pathogenesis of this disease. The emphasis on multifactorial pathways involved in developing DKD has highlighted some markers associated with tissue fibrosis. In diabetic nephropathy, TGF-β is significantly involved in its pathology. Its presence in serum and urine means that it could be a diagnostic tool while its regulation provides potential therapeutic targets. Completely blocking TGF-β signaling could reach untargeted regions and cause unanticipated effects. This paper reviews the basic details of TGF-β as a cytokine, its role in DKD, and updates on research carried out to validate its candidacy.

The KSR1/MEK/ERK signaling pathway promotes the progression of intrauterine adhesions

Kinase suppressor of Ras 1 (KSR1) serves as a scaffold protein within the RAS-RAF pathway and plays a role in tumorigenesis, immune regulation, cell proliferation, and apoptosis. However, the specific role of KSR1 in the formation and progression of fibrotic diseases, such as intrauterine adhesions (IUA), remains unclear. This study aims to investigate KSR1 expression in IUA and the mechanisms underlying its role in promoting IUA progression. KSR1 was found to be significantly overexpressed in the endometrium of both IUA model rats and patients with IUA. KSR1 is positively involved in the regulation of proliferation, migration, and fibrosis (FN1, Collagen I, α-SMA) in immortalized human endometrial stromal cells (THESCs). Furthermore, KSR1 knockdown was observed to inhibit the fibrosis, proliferation, and migration of transforming growth factor-β1 (TGF-β1)-induced THESCs. Further studies demonstrated that the key proteins of the MEK/ERK signaling pathway, p-MEK1 and p-ERK1/2, were significantly overexpressed in the uterus of IUA rats. In vitro rescue experiments confirmed that the MEK/ERK pathway inhibitor U0126 (An ERK inhibitor) effectively suppressed the enhanced fibrosis, proliferation, and migration induced by KSR1 overexpression. In conclusion, this study demonstrates that KSR1 promotes IUA by enhancing proliferation, migration, and fibrosis of endometrial stromal cells via the MEK/ERK signaling pathway.

Tryptanthrin alleviate lung fibrosis via suppression of MAPK/NF-κB and TGF-β1/SMAD signaling pathways in vitro and in vivo

Idiopathic pulmonary fibrosis (IPF), a progressive interstitial lung disease of unknown etiology, remains a therapeutic challenge with limited treatment options. This study investigates the therapeutic potential and molecular mechanisms of Tryptanthrin, a bioactive indole quinazoline alkaloid derived from Isatis tinctoria L., in pulmonary fibrosis. In a bleomycin-induced murine IPF model, Tryptanthrin administration (5 and 10 mg/kg/day for 28 days) significantly improved pulmonary function parameters and attenuated histological evidence of fibrosis. Mechanistic analysis revealed dual pathway modulation: Tryptanthrin suppressed MAPK/NF-κB signaling through inhibition of phosphorylation events, subsequently reducing pulmonary levels of pro-inflammatory cytokines (TNF-α, IL-1β, IL-6). Concurrently, it attenuated TGF-β1/Smad pathway activation by decreasing TGF-β1 expression and Smad2/3 phosphorylation, thereby downregulating fibrotic markers including COL1A1, α-smooth muscle actin (α-SMA), and fibronectin in lung tissues. Complementary in vitro studies using Lipopolysaccharide (LPS) or TGF-β1-stimulated NIH3T3 fibroblasts confirmed these anti-inflammatory and anti-fibrotic effects through analogous pathway inhibition. Our findings demonstrate that Tryptanthrin exerts therapeutic effects against pulmonary fibrosis via coordinated modulation of both inflammatory (MAPK/NF-κB) and fibrotic (TGF-β1/Smad) signaling cascades, suggesting its potential as a novel multi-target therapeutic agent for IPF management.

Neuroinflammation in kidney disease and dialysis

The complex relationship between chronic kidney disease (CKD) and neuroinflammation shows how important immunological processes are in mediating cognitive dysfunction and psychiatric symptoms in this disease. Proinflammatory cytokines and chemokines, such as IL-1β and IL-6, are capable of crossing the blood-brain barrier, and, consequently, may contribute to neuropsychiatric symptoms including anxiety, depression, and cognitive impairment in CKD patients. The peptides of the renin-angiotensin system (RAS), with their dual functions in inflammation and neuroprotection, also highlight the intricate immunological mechanisms operating within the kidney-brain axis. Understanding these immunological pathways is essential for developing targeted interventions to modulate neuroinflammation and improve cognitive outcomes in individuals with CKD. Further research in renal immunology and neuroinflammation holds promise for advancing our understanding of the intricate connections between kidney health, brain function, and immune responses in the context of CKD. This review summarizes the critical role of immunological factors in the pathophysiology of CKD-related cognitive impairment and psychiatric disorders.

TGF-β/SMAD Pathway Mediates Cadmium Poisoning-Induced Chicken Liver Fibrosis and Epithelial-Mesenchymal Transition

Cadmium(Cd) is a toxic heavy metal widely present in the environment, capable of accumulating in the liver and causing liver damage. In this study, the mechanism of cadmium-induced liver fibrosis in chickens was investigated from the perspective of hepatocyte epithelial-mesenchymal transition (EMT) based on the establishment of a model of chicken cadmium toxicity and a model of cadmium-stained cells in a chicken hepatocellular carcinoma cell line (LMH). The 7-day-old chickens were randomly divided into the regular group (C group) and cadmium poisoning group (Cd group), and the entire test cycle was 60 days. Three sampling time points of 20 days, 40 days, and 60 days were established. By testing the liver coefficient, histopathological and ultrastructural changes in chicken livers were observed. The enzyme activities of liver function and the expression changes of fibrosis markers (COL1A1, Fibronectin), epithelial-mesenchymal transition markers (E-cadherin, Vimentin, and α-SMA), and the critical factors of the TGF-β/SMAD signaling pathway (TGF-β1, SMAD 2, and SMAD 3) were detected in the liver expression changes. The results showed that at the same sampling time point, the chicken liver coefficient in group Cd was significantly higher than that in control group (P < 0.01); the activities of the liver function enzymes ALT and AST in chickens in the Cd group were significantly higher than those in the C group (P < 0.01); liver hepatocytes degenerated and necrotic, the number of erythrocytes in the blood vessels was increased, and inflammatory cells infiltrated in the sinusoidal gap; the perisinusoidal gap of the liver was enlarged, and there was an apparent aggregation of collagen fibers in the intervening period as seen by transmission electron microscopy. The results of Masson staining showed that the percentage of fiber area was significantly higher in the chickens' livers of the Cd group. The fiber area percentage was significantly higher. The results of real-time fluorescence quantitative PCR and Western Blot showed that the expression of E-cadherin in the livers of chickens in the Cd group was significantly lower than that in the C group (P < 0.01). The expression of α-SMA, Vimentin, COL1A1, Fibronectin, TGF-β1, SMAD 2, and SMAD 3 was significantly higher than that in the C group (P < 0.01). The results of in vitro assays showed that in the LMH cell model established by adding trimethylamine N-oxide, an activator of the TGF-β/SMAD signaling pathway, and oxidized picric acid, an inhibitor of the TGF-β/SMAD signaling pathway, the expression of E-cadherin was significantly reduced in cadmium-stained LMH cells (P < 0.01). The expression of α-SMA, Vimentin, COL1A1, Fibronectin, TGF-β, SMAD 2, and SMAD 3 was significantly elevated (P < 0.01). Cadmium and Trimethylamine N-oxide, an activator of the TGF-β/SMAD signaling pathway, promoted the expression of these factors. In contrast, the inhibitor of the TGF-β/SMAD signaling pathway, Oxymatrine, a TGF-β/SMAD signaling pathway inhibitor, significantly slowed down these changes. These results suggest that cadmium induces hepatic epithelial-mesenchymal transition by activating the TGF-β/SMAD signaling pathway in chicken hepatocytes, promoting hepatic fibrosis.

Research Progress on the Antifibrotic Activity of Traditional Chinese Medicine Polysaccharides

Fibrosis is a pathological process characterized by excessive extracellular matrix (ECM) deposition and proliferation fibrous tissue, a condition associated with various chronic diseases, such as liver cirrhosis, inflammation of the lungs, and myocarditis. Clinical treatment options for fibrotic diseases are currently limited and have poor efficacy. However, recent studies have increasingly demonstrated that polysaccharides exhibit significant antifibrotic activity by modulating cell proliferation and migration, inhibiting inflammation and oxidative stress associated fibrosis and regulating gut microbiota. This review provides an overview of recent advances in polysaccharide research for antifibrosis and offers new perspectives on the treatment of fibrotic diseases.

Mechanosensitive Ion Channel PIEZO1 as a Key Regulator of Intestinal Fibrosis in Crohn's Disease

BACKGROUND

We aimed to elucidate the function of the mechanosensitive ion channel PIEZO1 in intestinal fibrosis, which is invariably associated with Crohn's disease (CD) and often results in strictures and obstructions, requiring surgical intervention. Notably, PIEZO1 is strongly expressed in fibrotic tissues and linked with fibrotic progression.

METHODS

Intestinal tissues were procured from 28 patients diagnosed with CD and 8 healthy control subjects. Histological and immunofluorescence assays verified that PIEZO1 is substantially overexpressed in fibrotic intestinal tissues and is involved in epithelial‒mesenchymal transition (EMT). Further gene knockout experiments and transcriptome sequencing elucidated the specific role of PIEZO1 in the pathogenesis of intestinal fibrosis in CD. We generated mice with Piezo1 deletion specifically in intestinal epithelial cells (Piezo1f/f  Vilcre) to validate in vivo that inhibiting Piezo1 function attenuates or reverses intestinal fibrosis associated with CD.

RESULTS

PIEZO1 expression was strongly increased in the fibrotic small intestine of CD patients, thereby promoting EMT and exacerbating intestinal fibrosis. In vivo investigations revealed that the conditional suppression of Piezo1 in intestinal epithelial cells significantly mitigated intestinal fibrosis in dextran sulphate sodium (DSS)- and 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced chronic colitis model mice. In vitro examinations revealed that Piezo1 expression in intestinal epithelial cells preserved the stability of HIF-1α, induced EMT to stimulate the expression of fibrosis-associated molecules, and promoted fibrosis.

CONCLUSION

PIEZO1 plays a pivotal role in the regulation of intestinal fibrosis by maintaining the levels of HIF-1α, thereby promoting EMT. Therapeutic strategies targeting PIEZO1 could be used to prevent intestinal fibrosis in CD patients.

Radiation therapy-induced normal tissue damage: involvement of EMT pathways and role of FLASH-RT in reducing toxicities

Radiation therapy (RT) is fundamental to the fight against cancer because of its exceptional ability to target and destroy cancer cells. However, conventional radiation therapy can significantly affect the adjacent normal tissues, leading to fibrosis, inflammation, and decreased organ function. This tissue damage not only reduces the quality of life but also prevents the total elimination of cancer. The transformation of epithelial cells into mesenchymal-like cells, termed epithelial-mesenchymal transition (EMT), is essential for processes such as fibrosis, embryogenesis, and wound healing. Conventional radiation therapy increases the asymmetric activation of fibrotic and inflammatory pathways, and the resulting chronic fibrotic changes and organ dysfunction are linked to radiation-induced epithelial-mesenchymal transition. Recent advances in radiation therapy, namely flash radiation therapy (FLASH-RT), have the potential to widen the therapeutic index. Radiation delivered by FLASH-RT at very high dose rates (exceeding 40 Gy/s) can protect normal tissue from radiation-induced damage, a phenomenon referred to as the "FLASH effect". Preclinical studies have demonstrated that FLASH-RT successfully inhibits processes associated with fibrosis and epithelial-mesenchymal transition, mitigates damage to normal tissue, and enhances regeneration. Three distinct types of EMT have been identified: type-1, associated with embryogenesis; Type-2, associated with injury potential; and type-3, related with cancer spread. The regulation of EMT via pathways, including TGF-β/SMAD, WNT/β-catenin, and NF-κB, is essential for radiation-induced tissue remodelling. This study examined radiation-induced EMT, TGF-β activity, multiple signalling pathways in fibrosis, and the potential of FLASH-RT to reduce tissue damage. FLASH-RT is a novel approach to treat chronic tissue injury and fibrosis post-irradiation by maintaining epithelial properties and regulating mesenchymal markers including vimentin and N-cadherin. Understanding these pathways will facilitate the development of future therapies that can alleviate fibrosis, improve the efficacy of cancer therapy, and improve the quality of life of patients.

Skullcapflavone II suppresses TGF-β-induced corneal epithelial mesenchymal transition in vitro

AIM

To investigate the effect of skullcapflavone II (SCF-II) on the epithelial-mesenchymal transition (EMT) induced by transforming growth factor beta (TGF-β) in human corneal epithelial cells (HCECs), as well as to identify the signaling pathways that may be involved.

METHODS

HCECs were cultured in vitro. At a SCF-II (5, 10 µmol/L) dose, cell viability was analysed with a cell counting kit-8 (CCK-8) assay, and cell migration was monitored with wound healing and Transwell migration assays. There were 4 groups: SCF-II, TGF-β, SCF-II+TGF-β and Control. Western blotting and immunofluorescence were performed to show the expression of EMT markers and the translocation of nuclear factor kappa-B (NF-κB) into the nucleus in the 4 groups.

RESULTS

Treatment with SCF-II decreased HCEC viability in a dose-dependent manner. A concentration below 10 µmol/L did not present obvious cell toxicity, and survival rates were more than 70% at 48h. Treatment with SCF-II (5 and 10 µmol/L) significantly impeded migration in wound healing and Transwell migration assays (P<0.05), and EMT markers and NF-κB translocation into the nucleus were inhibited. After both TGF-β and SCF-II treatment, the migration of TGF-β-treated HCECs were suppressed by SCF-II (P<0.05). The expression levels of the mesenchymal markers N-cadherin (P<0.05), α-smooth muscle actin (α-SMA; P<0.05) and NF-κB (P<0.05) in both TGF-β- and SCF-II-treated HCECs were lower than those in the HCECs treated with TGF-β alone and higher than those in HCECs treated with SCF-II alone. Immunofluorescence showed that the entry of NF-κB into the nucleus in both TGF-β- and SCF-II-treated HCECs was less than that in the TGF-β-treated HCECs.

CONCLUSION

SCF-II inhibit TGF-β-induced EMT in HCECs by potentially regulating the NF-κB signalling pathway. Thus, SCF-II represents a candidate putative therapeutic agent in corneal fibrotic diseases.

Targeting epithelial-mesenchymal transition signaling pathways with Dietary Phytocompounds and repurposed drug combinations for overcoming drug resistance in various cancers

The epithelial-to-mesenchymal transition (EMT) is a crucial step in metastasis formation. It enhances the ability of cancer cells' to self-renew and initiate tumors, while also increasing resistance to apoptosis and chemotherapy. Among the signaling pathways a few signaling pathways such as Notch, TGF-beta, and Wnt-beta catenin are critically involved in the epithelial-to-mesenchymal transition (EMT) acquisition. Therefore, regulating EMT is a key strategy for controlling malignant cell behavior. This is done by interconnecting other signaling pathways in many cancer types. Although there is extensive preclinical evidence regarding EMT's function in the development of cancer, there is still a deficiency in clinical translation at the therapeutic level. Thus, there is a need for medications that are both highly effective and with low cytotoxic for modulating EMT transitions at ground level. Thus, this led to the study of the evaluation and efficiency of phytochemicals found in dietary sources of fruits and vegetables and also the combination of small molecular repurposed drugs that can enhance the effectiveness of traditional cancer treatments. This review summarises major EMT-associated pathways and their cross talks with their mechanistic insights and the role of different dietary phytochemicals (curcumin, ginger, fennel, black pepper, and clove) and their natural analogs and also repurposed drugs (metformin, statin, chloroquine, and vitamin D) which are commonly used in regulating EMT in various preclinical studies. This review also investigates the concept of low-toxicity and broad spectrum ("The Halifax Project") approach which can help for site targeting of several key pathways and their mechanism. We also discuss the mechanisms of action, models for our dietary phytochemicals, and repurposed drugs and their combinations used to identify potential anti-EMT activities. Additionally, we also analyzed existing literature and proposed new directions for accelerating the discovery of novel drug candidates that are safe to administer.

Role of E-cadherin in epithelial barrier dysfunction: implications for bacterial infection, inflammation, and disease pathogenesis

Epithelial barriers serve as critical defense lines against microbial infiltration and maintain tissue homeostasis. E-cadherin, an essential component of adherens junctions, has emerged as a pivotal molecule that secures epithelial homeostasis. Lately, its pleiotropic role beyond barrier function, including its involvement in immune responses, has become more evident. Herein, we delve into the intricate relationship between (dys)regulation of epithelial homeostasis and the versatile functionality of E-cadherin, describing complex mechanisms that underlie barrier integrity and disruption in disease pathogenesis such as bacterial infection and inflammation, among others. Clinical implications of E-cadherin perturbations in host pathophysiology are emphasized; downregulation, proteolytic phenomena, abnormal localization/signaling and aberrant immune reactions are linked with a broad spectrum of pathology beyond infectious diseases. Finally, potential therapeutic interventions that may harness E-cadherin to mitigate barrier-associated tissue damage are explored. Overall, this review highlights the crucial role of E-cadherin in systemic health, offering insights that could pave the way for strategies to reinforce/restore barrier integrity and treat related diseases.

Exploring the therapeutic potential of leriodenine and nuciferine from Nelumbo nucifera for renal fibrosis: an In-silico analysis

A major problem in chronic kidney illnesses is renal fibrosis. This research investigates the therapeutic potential of compounds derived from Nelumbo nucifera (Lotus). Comprehensive screening identified these compounds, which exhibit promising binding affinities with key targets associated with renal fibrosis. Leriodenine and Nuciferine demonstrate substantial potential by modulating critical targets such as PTGS2, JUN, EGFR, STAT3, mTOR, and AKT1. The identified biomolecule-target-pathway network highlights the intricate interactions underlying the therapeutic effects of lotus seed compounds in renal fibrosis. Strong binding affinities with PTGS2-PDBID:5F19, Leriodenine -8.99 kcal/mol and Nuciferine -9.33 kcal/mol, and JUN-PDBID:1S9K, Leriodenine -7.95 kcal/mol and Nuciferine -7.05 kcal/mol are shown by molecular docking investigations, indicating their potential as fibrotic process inhibitors. During 10 ns of molecular docking simulations, these compounds demonstrated robust hydrogen-bonding connections within the protein's active site, leading to a possible alteration in the conformation of the ligand-binding site. The research establishes the foundation for future experimental validation, clinical trials, to bridge the translational gap. The research combines target prediction, protein-protein interaction studies, and biomolecular screening to clarify the molecular pathways behind renal fibrosis. We also carried out Insilico molecular docking and carried out molecular dynamics simulation of the best compound identified to obtain more precise results.

Exploring the potential of TGFβ as a diagnostic marker and therapeutic target against cancer

Transforming Growth Factor-beta (TGF-β) is a multifunctional cytokine that exerts its biological effects through a complex process of activation and signaling. Initially synthesized in an inactive form bound to latency-associated peptide (LAP), TGF-β requires release from the extracellular matrix via proteolytic cleavage or integrin-mediated activation to engage with its receptors. Once active, TGF-β binds to type II receptor (TβRII), which then phosphorylates and activates type I receptor (TβRI), triggering downstream signaling cascades, including both Smad-dependent and non-Smad pathways. These signaling cascades regulate key processes like cell growth, differentiation, migration, and immune response modulation, thereby influencing tumor development, progression, and treatment outcomes. This review discusses the complex signaling pathways of TGF-β in cancer, including its interactions with other signaling molecules and its involvement in epithelial-mesenchymal transition (EMT) and in evading immune surveillance. Moreover, dysregulated TGF-β signaling due to alterations in receptor expression, mutations in key signaling proteins such as TβRII and Smads, and aberrant activation of non-canonical pathways, contributes significantly to tumor aggressiveness, metastasis, and therapy resistance. The article emphasizes the potential of TGF-β as a diagnostic biomarker for cancer, highlighting its use in early detection, prognosis assessment, and monitoring treatment response. Additionally, it underscores various therapeutic strategies targeting TGF-β, such as small molecule inhibitors, monoclonal antibodies, immunotherapies, and evaluates their efficacy and limitations in preclinical and clinical settings. Finally, the review provides a comprehensive analysis of TGF-β's role as both a diagnostic tool and a therapeutic target, while also discussing the challenges and opportunities in targeting TGF-β signaling for improving cancer treatment outcomes.

FBLN1 regulates ferroptosis in acute respiratory distress syndrome by reducing free ferrous iron by inhibiting the TGF-β/Smad pathway

BACKGROUND

Acute respiratory distress syndrome (ARDS) / acute lung injury (ALI) is a serious medical disease characterized by pulmonary dysfunction and inflammation. This study aims to determine the main molecular modules linked to ARDS and investigate the role of Fibulin-1 (FBLN1) in regulating ferroptosis in ARDS.

METHODS

Weighted Gene Co-expression Network Analysis (WGCNA) was employed on the GSE263867 dataset to find key modules associated with ALI. Differentially expressed genes (DEGs) and protein-protein interaction (PPI) networks were analyzed. MLE-12 cells were treated with lipopolysaccharide (LPS) to induce ferroptosis. In vitro studies were conducted to investigate the effects of FBLN1 and Transforming Growth Factor Beta 1 (TGF-β) overexpression on cell viability, oxidative stress markers, and ferroptosis-related proteins.

RESULTS

WGCNA identified the turquoise module as significantly negatively correlated with ARDS. Five key overlapping genes (GRIA1, OGN, COL14A1, FBLN1, and COL6A3) were significantly downregulated in ARDS samples. LPS treatment induced ferroptosis in MLE-12 cells, indicated by increased malondialdehyde (MDA), lipid reactive oxygen species (ROS), and ferrous iron (Fe2⁺) levels, and decreased cell viability and glutathione (GSH) levels. FBLN1 overexpression partially reversed these effects. Additionally, FBLN1 inhibited the TGF-β/Smad signaling pathway, as shown by decreased TGF-β and p-Smad protein levels. TGF-β overexpression exacerbated LPS-induced oxidative stress and ferroptosis, reducing cell viability and GSH levels. FBLN1 overexpression counteracted this effect, suggesting antagonistic roles for FBLN1 and TGF-β in regulating ferroptosis.

CONCLUSION

This study highlights FBLN1 as a critical regulator of ferroptosis in ARDS. Targeting the TGF-β/Smad pathway to modulate FBLN1 expression offers a potential therapeutic strategy to alleviate oxidative stress and mitigate pulmonary injury in inflammatory lung diseases.

Epithelial-mesenchymal transition to mitigate age-related progression in lung cancer

Epithelial-Mesenchymal Transition (EMT) is a fundamental biological process involved in embryonic development, wound healing, and cancer progression. In lung cancer, EMT is a key regulator of invasion and metastasis, significantly contributing to the fatal progression of the disease. Age-related factors such as cellular senescence, chronic inflammation, and epigenetic alterations exacerbate EMT, accelerating lung cancer development in the elderly. This review describes the complex mechanism among EMT and age-related pathways, highlighting key regulators such as TGF-β, WNT/β-catenin, NOTCH, and Hedgehog signalling. We also discuss the mechanisms by which oxidative stress, mediated through pathways involving NRF2 and ROS, telomere attrition, regulated by telomerase activity and shelterin complex, and immune system dysregulation, driven by alterations in cytokine profiles and immune cell senescence, upregulate or downregulate EMT induction. Additionally, we highlighted pathways of transcription such as SNAIL, TWIST, ZEB, SIRT1, TP53, NF-κB, and miRNAs regulating these processes. Understanding these mechanisms, we highlight potential therapeutic interventions targeting these critical molecules and pathways.

DsbA-L activates TGF-β1/SMAD3 signaling and M2 macrophage polarization by stimulating AKT1 and NLRP3 to promote pulmonary fibrosis

BACKGROUND

Pulmonary fibrosis (PF) is a progressive and difficult-to-heal lung disease that poses a significant threat to human life and health. This study aimed to investigate the potential pathological mechanisms of PF and to identify new avenues for the treatment of PF.

METHODS

Clinical samples were collected to assess the effect of disulfide-bond A oxidoreductase-like protein (DsbA-L) on PF. TGF-β1-induced MLE-12 cell model and bleomycin (BLM)-induced mice model were established. Changes in physiological morphology and fibrosis were observed in the lung tissues. The degree of apoptosis and the mitochondrial function was analyzed. The expression of relative cytokines was examined. The CD68+/CD206+ ratio was determined to indicate M2 macrophage polarization.

RESULTS

The expression of DsbA-L was upregulated in patients with PF and PF-like models. In vitro, DsbA-L overexpression exacerbated TGF-β1-induced the deposition of extracellular matrix (ECM), apoptosis, inflammation, and mitochondrial damage, whereas DsbA-L silencing exerted the opposite effects. DsbA-L silencing inhibited the activation of AKT1, NLRP3, and SMAD3 by TGF-β1. MLE-12 cells silencing DsbA-L limited the polarization of RAW264.7 cells towards the M2 phenotype. AKT1 agonist or NLRP3 agonist reversed the role of DsbA-L silencing in inhibiting the TGF-β1/SMAD3 pathway and M2 macrophage polarization. In vivo, DsbA-L knockout protected mice from PF-like pathological damage caused by BLM.

CONCLUSION

DsbA-L exhibited a significant profibrotic effect in lung epithelial cells and mice, which increased the levels of AKT1 and NLRP3 to activate the TGF-β1/SMAD3 pathway and M2 macrophage polarization. These findings could shed light on new clues for comprehension and treatment of PF.

New Insights into the Toxic Effects of Different Sizes of Nanosilica Particles in Food on the Mouse Bladder: Involving Epithelial-Mesenchymal Transition

Animals are widely exposed to nanosilica as a food additive. However, the negative effects of such nanosilica particles on animals' bladders are unclear. In the present study, we investigated the impact of MPs-SiO2 on mouse bladder and the underlying mechanisms. Mouse and MBEC cell models exposed to MPs-SiO2 with different particle sizes were established. At the same time, aminoguanidine hydrochloride (RNS inhibitor) and NF-κB activator were used to further explore its mechanism in vitro. We found that MPs-SiO2 of three sizes could induce RNS-induced pyroptosis causing EMT both in vitro and in vivo. After inhibiting RNS, the expression of related proteins in downstream pathways was decreased, and fibrosis was alleviated. The above situation was reversed by the addition of NF-κB activator. Furthermore, our data suggest that 300 nm MPs-SiO2 particles have a greater impact on the bladder than 50 nm particles. This study revealed the potential health risks of MPs-SiO2 and provided new insights into the toxicology of MPs-SiO2.

Exosomes on the development and progression of renal fibrosis

Renal fibrosis is a prevalent pathological alteration that occurs throughout the progression of primary and secondary renal disorders towards end-stage renal disease. As a complex and irreversible pathophysiological phenomenon, it includes a sequence of intricate regulatory processes at the molecular and cellular levels. Exosomes are a distinct category of extracellular vesicles that play a crucial role in facilitating intercellular communication. Multiple pathways are regulated by exosomes produced by various cell types, including tubular epithelial cells and mesenchymal stem cells, in the context of renal fibrosis. Furthermore, research has shown that exosomes present in bodily fluids, including urine and blood, may be indicators of renal fibrosis. However, the regulatory mechanism of exosomes in renal fibrosis has not been fully elucidated. This article reviewed and analysed the various mechanisms by which exosomes regulate renal fibrosis, which may provide new ideas for further study of the pathophysiological process of renal fibrosis and targeted treatment of renal fibrosis with exosomes.

MiR-125b-5p alleviates pulmonary fibrosis by inhibiting TGFβ1-mediated epithelial-mesenchymal transition via targeting BAK1

This study explores the role and potential mechanisms of microRNA-125b-5p (miR-125b-5p) in pulmonary fibrosis (PF). PF is a typical outcome of many chronic lung diseases, with poor prognosis and the lack of appropriate medical treatment because PF's molecular mechanisms remain poorly understood. In this study, using in vitro and in vivo analyses, we find that miR-125b-5p is likely a potent regulator of lung fibrosis. The findings reveal that, on the one hand, miR-125b-5p not only specifically decreases in the epithelial-mesenchymal transition (EMT) of lung epithelial cells, but also shows a downregulation trend in the lung tissues of mice with PF. On the other hand, overexpression of miR-125b-5p on the cellular and animal levels downregulates EMT and fibrotic phenotypes, respectively. To clarify the molecular mechanism of the "therapeutic" effect of miR-125b-5p, we use the target prediction tool combined with a dual luciferase assay and complete a rescue experiment by constructing the overexpression vector of the target gene Bcl-2 homologous antagonist/ killer (BAK1), thus confirming that miR-125b-5p can effectively inhibit EMT and fibrosis process by targeting BAK1 gene. MiR-125b-5p inhibits the EMT in lung epithelial cells by negatively regulating BAK1, while overexpression of miR-125b-5p can alleviate lung fibrosis. The findings suggest that MiR-125b-5p/BAK1 can serve as a potential treatment target for PF.

Immune and non-immune mediators in the fibrosis pathogenesis of salivary gland in Sjögren's syndrome

Sjögren's syndrome (SS) or Sjögren's disease (SjD) is a systemic autoimmune disease clinically manifested as sicca symptoms. This disease primarily impacts the functionality of exocrine glands, specifically the lacrimal and salivary glands (SG). SG fibrosis, an irreversible morphological change, is a severe consequence that occurs in the later stages of the disease due to sustained inflammation. However, the mechanism underlying SG fibrosis in SS remains under-investigated. Glandular fibrosis may arise from chronic sialadenitis, in which the interactions between infiltrating lymphocytes and epithelial cells potentially contributes to fibrotic pathogenesis. Thus, both immune and non-immune cells are closely involved in this process, while their interplays are not fully understood. The molecular mechanism of tissue fibrosis is partly associated with an imbalance of immune responses, in which the transforming growth factor-beta (TGF-β)-dependent epithelial-mesenchymal transition (EMT) and extracellular matrix remodeling are recently investigated. In addition, viral infection has been implicated in the pathogenesis of SS. Viral-specific innate immune response could exacerbate the autoimmune progression, resulting in overt inflammation in SG. Notably, post-COVID patients exhibit typical SS symptoms and severe inflammatory sialadenitis, which are positively correlated with SG damage. In this review, we discuss the immune and non-immune risk factors in SG fibrosis and summarize the evidence to understand the mechanisms upon autoimmune progression in SS.

Relationship of Signaling Pathways between RKIP Expression and the Inhibition of EMT-Inducing Transcription Factors SNAIL1/2, TWIST1/2 and ZEB1/2

Untreated primary carcinomas often lead to progression, invasion and metastasis, a process that involves the epithelial-to-mesenchymal transition (EMT). Several transcription factors (TFs) mediate the development of EMT, including SNAIL1/SNAIL2, TWIST1/TWIST2 and ZEB1/ZEB2, which are overexpressed in various carcinomas along with the under expression of the metastasis suppressor Raf Kinase Inhibitor Protein (RKIP). Overexpression of RKIP inhibits EMT and the above associated TFs. We, therefore, hypothesized that there are inhibitory cross-talk signaling pathways between RKIP and these TFs. Accordingly, we analyzed the various properties and biomarkers associated with the epithelial and mesenchymal tissues and the various molecular signaling pathways that trigger the EMT phenotype such as the TGF-β, the RTK and the Wnt pathways. We also presented the various functions and the transcriptional, post-transcriptional and epigenetic regulations for the expression of each of the EMT TFs. Likewise, we describe the transcriptional, post-transcriptional and epigenetic regulations of RKIP expression. Various signaling pathways mediated by RKIP, including the Raf/MEK/ERK pathway, inhibit the TFs associated with EMT and the stabilization of epithelial E-Cadherin expression. The inverse relationship between RKIP and the TF expressions and the cross-talks were further analyzed by bioinformatic analysis. High mRNA levels of RKIP correlated negatively with those of SNAIL1, SNAIL2, TWIST1, TWIST2, ZEB1, and ZEB2 in several but not all carcinomas. However, in these carcinomas, high levels of RKIP were associated with good prognosis, whereas high levels of the above transcription factors were associated with poor prognosis. Based on the inverse relationship between RKIP and EMT TFs, it is postulated that the expression level of RKIP in various carcinomas is clinically relevant as both a prognostic and diagnostic biomarker. In addition, targeting RKIP induction by agonists, gene therapy and immunotherapy will result not only in the inhibition of EMT and metastases in carcinomas, but also in the inhibition of tumor growth and reversal of resistance to various therapeutic strategies. However, such targeting strategies must be better investigated as a result of tumor heterogeneities and inherent resistance and should be better adapted as personalized medicine.

Identification of critical genes and metabolic pathways in rheumatoid arthritis and osteoporosis toward drug repurposing

BACKGROUND

Rheumatoid arthritis (RA) and osteoporosis (OP) are considered to be complex diseases. In recent studies, a positive association between RA and OP has been reported triggering growing research interest. This study aims to investigate the drugs related to critical genes in RA and OP, using bioinformatics approaches, toward drug repurposing.

METHOD

RA and OP genes were identified. The RA-OP PPI network was constructed and analyzed using the STRING and Cytoscape, respectively. Hub genes and modules were extracted and enriched Gene Ontology, through the WebGestalt and g:Profiler. The identification of the drugs related to critical genes using the DGIDB, and extracted the miRNAs using miRWalk and miRNet.

RESULTS

By network clustering, five significant modules were obtained that have important roles in the immune system. IL6, TNF, IL1B, STAT3, TGFB1, TP53, HIF1A, CCL2, IL10, and MMP9 were found as the top 10 hub genes in the RA-OP network. Hub genes were shown to have implications in inflammatory response, significant functions in cytokine receptor binding, and localized mostly in extracellular space. By investigating the drugs related to hub genes, 16 drugs were identified as repurposing candidate drugs. The 10 drugs included Hydroxychloroquine, Infliximab, Adalimumab, Etanercept, Certolizumab, Cyclosporine, Diacerein, Gevokizumab, Canakinumab, and Olokizumab proposed for OP. Also, six drugs including Pirfenidone, Pentoxifylline, Vadimezan, Rilonacept, Metelimumab, and Siltuximab have important roles in inflammatory control and were proposed for both RA and OP.

CONCLUSIONS

The results of the present study can provide novel insights into the pathogenesis and treatment of RA and OP.

RMRP accelerates ligamentum flavum hypertrophy by regulating GSDMD-mediated pyroptosis through Gli1 SUMOylation

Hypertrophy of ligamentum flavum (LF) is a significant contributing factor to lumbar spinal canal stenosis (LSCS). lncRNA plays a vital role in organ fibrosis, but its role in LF fibrosis remains unclear. Our previous findings have demonstrated that Hedgehog-Gli1 signaling is a critical driver leading to LF hypertrophy. Through the RIP experiment, our group found lnc-RMRP was physically associated with Gli1 and exhibited enrichment in Gli1-activated LF cells. Histological studies revealed elevated expression of RMRP in hypertrophic LF. In vitro experiments further confirmed that RMRP promoted Gli1 SUMO modification and nucleus transfer. Mechanistically, RMRP induced GSDMD-mediated pyroptosis, proinflammatory activation, and collagen expression through the Hedgehog pathway. Notably, the mechanical stress-induced hypertrophy of LF in rabbit exhibited analogous pathological changes of LF fibrosis occurred in human and showed enhanced levels of collagen and α-SMA. Knockdown of RMRP resulted in the decreased expression of fibrosis and pyroptosis-related proteins, ultimately ameliorating fibrosis. The above data concluded that RMRP exerts a crucial role in regulating GSDMD-mediated pyroptosis of LF cells via Gli1 SUMOylation, thus indicating that targeting RMRP could serve as a potential and effective therapeutic strategy for LF hypertrophy and fibrosis.

IL-1β-activated PI3K/AKT and MEK/ERK pathways coordinately promote induction of partial epithelial-mesenchymal transition

Epithelial-mesenchymal transition (EMT) is a cellular process in embryonic development, wound healing, organ fibrosis, and cancer metastasis. Previously, we and others have reported that proinflammatory cytokine interleukin-1β (IL-1β) induces EMT. However, the exact mechanisms, especially the signal transduction pathways, underlying IL-1β-mediated EMT are not yet completely understood. Here, we found that IL-1β stimulation leads to the partial EMT-like phenotype in human lung epithelial A549 cells, including the gain of mesenchymal marker (vimentin) and high migratory potential, without the complete loss of epithelial marker (E-cadherin). IL-1β-mediated partial EMT induction was repressed by PI3K inhibitor LY294002, indicating that the PI3K/AKT pathway plays a significant role in the induction. In addition, ERK1/2 inhibitor FR180204 markedly inhibited the IL-1β-mediated partial EMT induction, demonstrating that the MEK/ERK pathway was also involved in the induction. Furthermore, we found that the activation of the PI3K/AKT and MEK/ERK pathways occurred downstream of the epidermal growth factor receptor (EGFR) pathway and the IL-1 receptor (IL-1R) pathway, respectively. Our findings suggest that the PI3K/AKT and MEK/ERK pathways coordinately promote the IL-1β-mediated partial EMT induction. The inhibition of not one but both pathways is expected yield clinical benefits by preventing partial EMT-related disorders such as organ fibrosis and cancer metastasis.

Fibrosis-on-Chip: A Guide to Recapitulate the Essential Features of Fibrotic Disease

Fibrosis, which is primarily marked by excessive extracellular matrix (ECM) deposition, is a pathophysiological process associated with many disorders, which ultimately leads to organ dysfunction and poor patient outcomes. Despite the high prevalence of fibrosis, currently there exist few therapeutic options, and importantly, there is a paucity of in vitro models to accurately study fibrosis. This review discusses the multifaceted nature of fibrosis from the viewpoint of developing organ-on-chip (OoC) disease models, focusing on five key features: the ECM component, inflammation, mechanical cues, hypoxia, and vascularization. The potential of OoC technology is explored for better modeling these features in the context of studying fibrotic diseases and the interplay between various key features is emphasized. This paper reviews how organ-specific fibrotic diseases are modeled in OoC platforms, which elements are included in these existing models, and the avenues for novel research directions are highlighted. Finally, this review concludes with a perspective on how to address the current gap with respect to the inclusion of multiple features to yield more sophisticated and relevant models of fibrotic diseases in an OoC format.

Epicardial EMT and cardiac repair: an update

Epicardial epithelial-to-mesenchymal transition (EMT) plays a pivotal role in both heart development and injury response and involves dynamic cellular changes that are essential for cardiogenesis and myocardial repair. Specifically, epicardial EMT is a crucial process in which epicardial cells lose polarity, migrate into the myocardium, and differentiate into various cardiac cell types during development and repair. Importantly, following EMT, the epicardium becomes a source of paracrine factors that support cardiac growth at the last stages of cardiogenesis and contribute to cardiac remodeling after injury. As such, EMT seems to represent a fundamental step in cardiac repair. Nevertheless, endogenous EMT alone is insufficient to stimulate adequate repair. Redirecting and amplifying epicardial EMT pathways offers promising avenues for the development of innovative therapeutic strategies and treatment approaches for heart disease. In this review, we present a synthesis of recent literature highlighting the significance of epicardial EMT reactivation in adult heart disease patients.

Simulated gastrointestinal digestion of walnut protein yields anti-inflammatory peptides

The impact of the simulated gastrointestinal digestion process on walnut protein and the potential anti-inflammatory properties of its metabolites was studied. Structural changes induced by digestion, notably in α-Helix, β-Turn, and Random Coil configurations, were unveiled. Proteins over 10,000 Da significantly decreased by 35.6 %. Antioxidant activity in these metabolites paralleled increased amino acid content. Molecular docking identified three walnut polypeptides-IPAGTPVYLINR, FQGQLPR, and VVYVLR-with potent anti-inflammatory properties. RMSD and RMSF analysis demonstrated the stable and flexible interaction of these polypeptides with their target proteins. In lipopolysaccharide (LPS)-induced inflammation in normal human colon mucosal epithelial NCM460 cells, these peptides decreased 5-hydroxytryptamine (5-HT), tumor necrosis factor-alpha (TNF-α), and vascular endothelial growth factor (VEGF) expression, while mitigating cell apoptosis and inflammation. Our study offers valuable insights into walnut protein physiology, shedding light on its potential health benefits.

Acute and Long COVID Intestinal Changes in an Experimental Model of Coronavirus in Mice

The COVID-19 pandemic, which emerged in early 2020, has had a profound and lasting impact on global health, resulting in over 7.0 million deaths and persistent challenges. In addition to acute concerns, there is growing attention being given to the long COVID health consequences for survivors of COVID-19 with documented cases of cardiovascular abnormalities, liver disturbances, lung complications, kidney issues, and noticeable cognitive deficits. Recent studies have investigated the physiological changes in various organs following prolonged exposure to murine hepatitis virus-1 (MHV-1), a coronavirus, in mouse models. One significant finding relates to the effects on the gastrointestinal tract, an area previously understudied regarding the long-lasting effects of COVID-19. This research sheds light on important observations in the intestines during both the acute and the prolonged phases following MHV-1 infection, which parallel specific changes seen in humans after exposure to SARS-CoV-2. Our study investigates the histopathological alterations in the small intestine following MHV-1 infection in murine models, revealing significant changes reminiscent of inflammatory bowel disease (IBD), celiac disease. Notable findings include mucosal inflammation, lymphoid hyperplasia, goblet cell hyperplasia, and immune cell infiltration, mirroring pathological features observed in IBD. Additionally, MHV-1 infection induces villous atrophy, altered epithelial integrity, and inflammatory responses akin to celiac disease and IBD. SPIKENET (SPK) treatment effectively mitigates intestinal damage caused by MHV-1 infection, restoring tissue architecture and ameliorating inflammatory responses. Furthermore, investigation into long COVID reveals intricate inflammatory profiles, highlighting the potential of SPK to modulate intestinal responses and restore tissue homeostasis. Understanding these histopathological alterations provides valuable insights into the pathogenesis of COVID-induced gastrointestinal complications and informs the development of targeted therapeutic strategies.

SPIKENET: An Evidence-Based Therapy for Long COVID

The COVID-19 pandemic has been one of the most impactful events in our lifetime, caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Multiple SARS-CoV-2 variants were reported globally, and a wide range of symptoms existed. Individuals who contract COVID-19 continue to suffer for a long time, known as long COVID or post-acute sequelae of COVID-19 (PASC). While COVID-19 vaccines were widely deployed, both unvaccinated and vaccinated individuals experienced long-term complications. To date, there are no treatments to eradicate long COVID. We recently conceived a new approach to treat COVID in which a 15-amino-acid synthetic peptide (SPIKENET, SPK) is targeted to the ACE2 receptor binding domain of SARS-CoV-2, which prevents the virus from attaching to the host. We also found that SPK precludes the binding of spike glycoproteins with the receptor carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) of a coronavirus, murine hepatitis virus-1 (MHV-1), and with all SARS-CoV-2 variants. Further, SPK reversed the development of severe inflammation, oxidative stress, tissue edema, and animal death post-MHV-1 infection in mice. SPK also protects against multiple organ damage in acute and long-term post-MHV-1 infection. Our findings collectively suggest a potential therapeutic benefit of SPK for treating COVID-19.

Coenzyme Q0 inhibited the NLRP3 inflammasome, metastasis/EMT, and Warburg effect by suppressing hypoxia-induced HIF-1α expression in HNSCC cells

Coenzyme Q0 (CoQ0), a quinone derivative from Antrodia camphorata, has antitumor capabilities. This study investigated the antitumor effect of noncytotoxic CoQ0, which included NLRP3 inflammasome inhibition, anti-EMT/metastasis, and metabolic reprogramming via HIF-1α inhibition, in HNSCC cells under normoxia and hypoxia. CoQ0 suppressed hypoxia-induced ROS-mediated HIF-1α expression in OECM-1 and SAS cells. Under normoxia and hypoxia, the inflammatory NLRP3, ASC/caspase-1, NFκB, and IL-1β expression was reduced by CoQ0. CoQ0 reduced migration/invasion by enhancing epithelial marker E-cadherin and suppressing mesenchymal markers Twist, N-cadherin, Snail, and MMP-9, and MMP-2 expression. CoQ0 inhibited glucose uptake, lactate accumulation, GLUT1 levels, and HIF-1α-target gene (HK-2, PFK-1, and LDH-A) expressions that are involved in aerobic glycolysis. Notably, CoQ0 reduced ECAR as well as glycolysis, glycolytic capability, and glycolytic reserve and enhanced OCR, basal respiration, ATP generation, maximal respiration, and spare capacity in OECM-1 cells. Metabolomic analysis using LC-ESI-MS showed that CoQ0 treatment decreased the levels of glycolytic intermediates, including lactate, 2/3-phosphoglycerate, fructose 1,6-bisphosphate, and phosphoenolpyruvate, and increased the levels of TCA cycle metabolites, including citrate, isocitrate, and succinate. HIF-1α silencing reversed CoQ0-mediated anti-metastasis (N-Cadherin, Snail, and MMP-9) and metabolic reprogramming (GLUT1, HK-2, and PKM-2) under hypoxia. CoQ0 prevents cancer stem-like characteristics (upregulated CD24 expression and downregulated CD44, ALDH1, and OCT4) under normoxia and/or hypoxia. Further, in IL-6-treated SG cells, CoQ0 attenuated fibrosis by inhibiting TGF-β and Collagen I expression and suppressed EMT by downregulating Slug and upregulating E-cadherin expression. Interesting, CoQ0 inhibited the growth of OECM-1 tumors in xenografted mice. Our results advocate CoQ0 for the therapeutic application against HNSCC.

Cell type-specific transforming growth factor-β (TGF-β) signaling in the regulation of salivary gland fibrosis and regeneration

Salivary gland damage and hypofunction result from various disorders, including autoimmune Sjögren's disease (SjD) and IgG4-related disease (IgG4-RD), as well as a side effect of radiotherapy for treating head and neck cancers. There are no therapeutic strategies to prevent the loss of salivary gland function in these disorders nor facilitate functional salivary gland regeneration. However, ongoing aquaporin-1 gene therapy trials to restore saliva flow show promise. To identify and develop novel therapeutic targets, we must better understand the cell-specific signaling processes involved in salivary gland regeneration. Transforming growth factor-β (TGF-β) signaling is essential to tissue fibrosis, a major endpoint in salivary gland degeneration, which develops in the salivary glands of patients with SjD, IgG4-RD, and radiation-induced damage. Though the deposition and remodeling of extracellular matrix proteins are essential to repair salivary gland damage, pathological fibrosis results in tissue hardening and chronic salivary gland dysfunction orchestrated by multiple cell types, including fibroblasts, myofibroblasts, endothelial cells, stromal cells, and lymphocytes, macrophages, and other immune cell populations. This review is focused on the role of TGF-β signaling in the development of salivary gland fibrosis and the potential for targeting TGF-β as a novel therapeutic approach to regenerate functional salivary glands. The studies presented highlight the divergent roles of TGF-β signaling in salivary gland development and dysfunction and illuminate specific cell populations in damaged or diseased salivary glands that mediate the effects of TGF-β. Overall, these studies strongly support the premise that blocking TGF-β signaling holds promise for the regeneration of functional salivary glands.

From inflammation to renal fibrosis: A one-way road in autoimmunity?

Renal fibrosis is now recognized as a main determinant of renal pathology to include chronic kidney disease. Deposition of pathological matrix in the walls of glomerular capillaries, the interstitial space, and around arterioles predicts and contributes to the functional demise of the nephron and its surrounding vasculature. The recent identification of the major cell populations of fibroblast precursors in the kidney interstitium such as pericytes and tissue-resident mesenchymal stem cells, or bone-marrow-derived macrophages, and in the glomerulus such as podocytes, parietal epithelial and mesangial cells, has enabled the study of the fibrogenic process thought the lens of involved immunological pathways. Besides, a growing body of evidence is supporting the role of the lymphatic system in modulating the immunological response potentially leading to inflammation and ultimately renal damage. These notions have moved our understanding of renal fibrosis to be recognized as a clinical entity and new main player in autoimmunity, impacting directly the management of patients.

Knockdown of Notch Suppresses Epithelial-mesenchymal Transition and Induces Angiogenesis in Oral Submucous Fibrosis by Regulating TGF-β1

Oral submucous fibrosis (OSF) is a chronic disorder with a high malignant transformation rate. Epithelial-mesenchymal transition (EMT) and angiogenesis are key events in OSF. The Notch signaling plays an essential role in the pathogenesis of various fibrotic diseases, including OSF. Our study aimed to explore the effects of Notch on the EMT and angiogenesis processes during the development of OSF. The expression of Notch in OSF tissues versus normal buccal mucosa samples was compared. Arecoline was used to induce myofibroblast transdifferentiation of buccal mucosal fibroblasts (BMFs). Short hairpin RNA technique was used to knockdown Notch in BMFs. Pirfenidone and SRI-011381 were used to inhibit and activate the TGF-β1 signaling pathway in BMFs, respectively. The expression of Notch was markedly upregulated in OSF tissues and fibrotic BMFs. Knockdown of Notch significantly decreased the viability and promoted apoptosis in BMFs subjected to arecoline stimulation. Downregulation of Notch also significantly suppressed the EMT process, as shown by the reduction of N-cadherin and vimentin with concomitant upregulation of E-cadherin. In addition, knockdown of Notch upregulated VEGF and enhanced the angiogenic activity of fBMFs. Moreover, inhibition of TGF-β1 suppressed viability and EMT, promoted apoptosis, and induced angiogenesis of fBMFs, while activation of TGF-β1 significantly diminished the effects of Notch knockdown on fBMFs. Knockdown of Notch suppressed EMT and induced angiogenesis in OSF by regulating TGF-β1, suggesting that the Notch-TGF-β1 pathway may serve as a therapeutic intervention target for OSF.

Single-cell RNA-seq reveals keratinocyte and fibroblast heterogeneity and their crosstalk via epithelial-mesenchymal transition in psoriasis

The pathogenesis of psoriasis, a chronic inflammatory autoimmune skin disease with a high global prevalence, remains unclear. We performed a high-resolution single-cell RNA sequencing analysis of 94,759 cells from 13 samples, including those from psoriasis model mice and wild-type mice. We presented a single-cell atlas of the skin of imiquimod-induced mice with psoriasis and WT mice, especially the heterogeneity of keratinocytes and fibroblasts. More interestingly, we discovered that special keratinocyte subtypes and fibroblast subtypes could interact with each other through epithelial-mesenchymal transition and validated the results with drug verification. Moreover, we conducted a tentative exploration of the potential pathways involved and revealed that the IL-17 signalling pathway may be the most relevant pathway. Collectively, we revealed the full-cycle landscape of key cells associated with psoriasis and provided a more comprehensive understanding of the pathogenesis of psoriasis.

Epigenetic Regulation of EMP/EMT-Dependent Fibrosis

Fibrosis represents a process characterized by excessive deposition of extracellular matrix (ECM) proteins. It often represents the evolution of pathological conditions, causes organ failure, and can, in extreme cases, compromise the functionality of organs to the point of causing death. In recent years, considerable efforts have been made to understand the molecular mechanisms underlying fibrotic evolution and to identify possible therapeutic strategies. Great interest has been aroused by the discovery of a molecular association between epithelial to mesenchymal plasticity (EMP), in particular epithelial to mesenchymal transition (EMT), and fibrogenesis, which has led to the identification of complex molecular mechanisms closely interconnected with each other, which could explain EMT-dependent fibrosis. However, the result remains unsatisfactory from a therapeutic point of view. In recent years, advances in epigenetics, based on chromatin remodeling through various histone modifications or through the intervention of non-coding RNAs (ncRNAs), have provided more information on the fibrotic process, and this could represent a promising path forward for the identification of innovative therapeutic strategies for organ fibrosis. In this review, we summarize current research on epigenetic mechanisms involved in organ fibrosis, with a focus on epigenetic regulation of EMP/EMT-dependent fibrosis.

Deciphering the fibrotic process: mechanism of chronic radiation skin injury fibrosis

This review explores the mechanisms of chronic radiation-induced skin injury fibrosis, focusing on the transition from acute radiation damage to a chronic fibrotic state. It reviewed the cellular and molecular responses of the skin to radiation, highlighting the role of myofibroblasts and the significant impact of Transforming Growth Factor-beta (TGF-β) in promoting fibroblast-to-myofibroblast transformation. The review delves into the epigenetic regulation of fibrotic gene expression, the contribution of extracellular matrix proteins to the fibrotic microenvironment, and the regulation of the immune system in the context of fibrosis. Additionally, it discusses the potential of biomaterials and artificial intelligence in medical research to advance the understanding and treatment of radiation-induced skin fibrosis, suggesting future directions involving bioinformatics and personalized therapeutic strategies to enhance patient quality of life.

Multifaceted TGF-β signaling, a master regulator: From bench-to-bedside, intricacies, and complexities

Physiological embryogenesis and adult tissue homeostasis are regulated by transforming growth factor-β (TGF-β), an evolutionarily conserved family of secreted polypeptide factors, acting in an autocrine and paracrine manner. The role of TGF-β in inflammation, fibrosis, and cancer is complex and sometimes even contradictory, exhibiting either inhibitory or promoting effects depending on the stage of the disease. Under pathological conditions, especially fibrosis and cancer, overexpressed TGF-β causes extracellular matrix deposition, epithelial-mesenchymal transition, cancer-associated fibroblast formation, and/or angiogenesis. In this review article, we have tried to dive deep into the mechanism of action of TGF-β in inflammation, fibrosis, and carcinogenesis. As TGF-β and its downstream signaling mechanism are implicated in fibrosis and carcinogenesis blocking this signaling mechanism appears to be a promising avenue. However, targeting TGF-β carries substantial risk as this pathway is implicated in multiple homeostatic processes and is also known to have tumor-suppressor functions. There is a need for careful dosing of TGF-β drugs for therapeutic use and patient selection.

Biomimetic Corneal Stroma for Scarless Corneal Wound Healing via Structural Restoration and Microenvironment Modulation

Corneal injury-induced stromal scarring causes the most common subtype of corneal blindness, and there is an unmet need to promote scarless corneal wound healing. Herein, a biomimetic corneal stroma with immunomodulatory properties is bioengineered for scarless corneal defect repair. First, a fully defined serum-free system is established to derive stromal keratocytes (hAESC-SKs) from a current Good Manufacturing Practice (cGMP)-grade human amniotic epithelial stem cells (hAESCs), and RNA-seq is used to validate the phenotypic transition. Moreover, hAESC-SKs are shown to possess robust immunomodulatory properties in addition to the keratocyte phenotype. Inspired by the corneal stromal extracellular matrix (ECM), a photocurable gelatin-based hydrogel is fabricated to serve as a scaffold for hAESC-SKs for bioengineering of a biomimetic corneal stroma. The rabbit corneal defect model is used to confirm that this biomimetic corneal stroma rapidly restores the corneal structure, and effectively reshapes the tissue microenvironment via proteoglycan secretion to promote transparency and inhibition of the inflammatory cascade to alleviate fibrosis, which synergistically reduces scar formation by ≈75% in addition to promoting wound healing. Overall, the strategy proposed here provides a promising solution for scarless corneal defect repair.

Dermatologic Changes in Experimental Model of Long COVID

The coronavirus disease-19 (COVID-19) pandemic, declared in early 2020, has left an indelible mark on global health, with over 7.0 million deaths and persistent challenges. While the pharmaceutical industry raced to develop vaccines, the emergence of mutant severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) strains continues to pose a significant threat. Beyond the immediate concerns, the long-term health repercussions of COVID-19 survivors are garnering attention, particularly due to documented cases of cardiovascular issues, liver dysfunction, pulmonary complications, kidney impairments, and notable neurocognitive deficits. Recent studies have delved into the pathophysiological changes in various organs following post-acute infection with murine hepatitis virus-1 (MHV-1), a coronavirus, in mice. One aspect that stands out is the impact on the skin, a previously underexplored facet of long-term COVID-19 effects. The research reveals significant cutaneous findings during both the acute and long-term phases post-MHV-1 infection, mirroring certain alterations observed in humans post-SARS-CoV-2 infection. In the acute stages, mice exhibited destruction of the epidermal layer, increased hair follicles, extensive collagen deposition in the dermal layer, and hyperplasticity of sebaceous glands. Moreover, the thinning of the panniculus carnosus and adventitial layer was noted, consistent with human studies. A long-term investigation revealed the absence of hair follicles, destruction of adipose tissues, and further damage to the epidermal layer. Remarkably, treatment with a synthetic peptide, SPIKENET (SPK), designed to prevent Spike glycoprotein-1 binding with host receptors and elicit a potent anti-inflammatory response, showed protection against MHV-1 infection. Precisely, SPK treatment restored hair follicle loss in MHV-1 infection, re-architected the epidermal and dermal layers, and successfully overhauled fatty tissue destruction. These promising findings underscore the potential of SPK as a therapeutic intervention to prevent long-term skin alterations initiated by SARS-CoV-2, providing a glimmer of hope in the battle against the lingering effects of the pandemic.

The role of mitochondrial dysfunction in macrophages on SiO2 -induced pulmonary fibrosis: A review

Several epidemiologic and toxicological studies have widely regarded that mitochondrial dysfunction is a popular molecular event in the process of silicosis from different perspectives, but the details have not been systematically summarized yet. Thus, it is necessary to investigate how silica dust leads to pulmonary fibrosis by damaging the mitochondria of macrophages. In this review, we first introduce the molecular mechanisms that silica dust induce mitochondrial morphological and functional abnormalities and then introduce the main molecular mechanisms that silica-damaged mitochondria induce pulmonary fibrosis. Finally, we conclude that the mitochondrial abnormalities of alveolar macrophages caused by silica dust are involved deeply in the pathogenesis of silicosis through these two sequential mechanisms. Therefore, reducing the silica-damaged mitochondria will prevent the potential occurrence and fatality of the disease in the future.

Targeting Interleukin-17 as a Novel Treatment Option for Fibrotic Diseases

Fibrosis is the end result of persistent inflammatory responses induced by a variety of stimuli, including chronic infections, autoimmune reactions, and tissue injury. Fibrotic diseases affect all vital organs and are characterized by a high rate of morbidity and mortality in the developed world. Until recently, there were no approved antifibrotic therapies. In recent years, high levels of interleukin-17 (IL-17) have been associated with chronic inflammatory diseases with fibrotic complications that culminate in organ failure. In this review, we provide an update on the role of IL-17 in fibrotic diseases, with particular attention to the most recent lines of research in the therapeutic field represented by the epigenetic mechanisms that control IL-17 levels in fibrosis. A better knowledge of the IL-17 signaling pathway implications in fibrosis could design new strategies for therapeutic benefits.

Prospective therapeutics for intestinal and hepatic fibrosis

Currently, there are no effective therapies for intestinal and hepatic fibrosis representing a considerable unmet need. Breakthroughs in pathogenesis have accelerated the development of anti-fibrotic therapeutics in recent years. Particularly, with the development of nanotechnology, the harsh environment of the gastrointestinal tract and inaccessible microenvironment of fibrotic lesions seem to be no longer considered a great barrier to the use of anti-fibrotic drugs. In this review, we comprehensively summarize recent preclinical and clinical studies on intestinal and hepatic fibrosis. It is found that the targets for preclinical studies on intestinal fibrosis is varied, which could be divided into molecular, cellular, and tissues level, although little clinical trials are ongoing. Liver fibrosis clinical trials have focused on improving metabolic disorders, preventing the activation and proliferation of hepatic stellate cells, promoting the degradation of collagen, and reducing inflammation and cell death. At the preclinical stage, the therapeutic strategies have focused on drug targets and delivery systems. At last, promising remedies to the current challenges are based on multi-modal synergistic and targeted delivery therapies through mesenchymal stem cells, nanotechnology, and gut-liver axis providing useful insights into anti-fibrotic strategies for clinical use.

Transcriptomic and proteomic profiling reveals distinct pathogenic features of peripheral non-classical monocytes in systemic lupus erythematosus

Peripheral blood monocytes propagate inflammation in systemic lupus erythematosus (SLE). Three major populations of monocytes have been recognized namely classical (CM), intermediate (IM) and non-classical monocytes (NCM). Herein, we performed a comprehensive transcriptomic, proteomic and functional characterization of the three peripheral monocytic subsets from active SLE patients and healthy individuals. Our data demonstrate extensive molecular disruptions in circulating SLE NCM, characterized by enhanced inflammatory features such as deregulated DNA repair, cell cycle and heightened IFN signaling combined with differentiation and developmental cues. Enhanced DNA damage, elevated expression of p53, G0 arrest of cell cycle and increased autophagy stress the differentiation potential of NCM in SLE. This immunogenic profile is associated with an activated macrophage phenotype of NCM exhibiting M1 characteristics in the circulation, fueling the inflammatory response. Together, these findings identify circulating SLE NCM as a pathogenic cell type in the disease that could represent an additional therapeutic target.

A unique cell population expressing the Epithelial-Mesenchymal Transition-transcription factor Snail moderates microglial and astrocyte injury responses

Insults to the central nervous system (CNS) elicit common glial responses including microglial activation evidenced by functional, morphological, and phenotypic changes, as well as astrocyte reactions including hypertrophy, altered process orientation, and changes in gene expression and function. However, the cellular and molecular mechanisms that initiate and modulate such glial response are less well-defined. Here we show that an adult cortical lesion generates a population of ultrastructurally unique microglial-like cells that express Epithelial-Mesenchymal Transcription factors including Snail. Knockdown of Snail with antisense oligonucleotides results in a postinjury increase in activated microglial cells, elevation in astrocyte reactivity with increased expression of C3 and phagocytosis, disruption of astrocyte junctions and neurovascular structure, increases in neuronal cell death, and reduction in cortical synapses. These changes were associated with alterations in pro-inflammatory cytokine expression. By contrast, overexpression of Snail through microglia-targeted an adeno-associated virus (AAV) improved many of the injury characteristics. Together, our results suggest that the coordination of glial responses to CNS injury is partly mediated by epithelial-mesenchymal transition-factors (EMT-Fsl).

Interleukin-23 Involved in Fibrotic Autoimmune Diseases: New Discoveries

Interleukin (IL)-23 is a central pro-inflammatory cytokine with a broad range of effects on immune responses. IL-23 is pathologically linked to the induction of the production of the pro-inflammatory cytokines IL-17 and IL-22, which stimulate the differentiation and proliferation of T helper type 17 (Th17) cells. Recent discoveries suggest a potential pro-fibrotic role for IL-23 in the development of chronic inflammatory autoimmune diseases characterized by intense fibrosis. In this review, we summarized the biological features of IL-23 and gathered recent research on the role of IL-23 in fibrotic autoimmune conditions, which could provide a theoretical basis for clinical targeting and drug development.

Epithelial-Mesenchymal Transition Mechanisms in Chronic Airway Diseases: A Common Process to Target?

Epithelial-to-mesenchymal transition (EMT) is a reversible process, in which epithelial cells lose their epithelial traits and acquire a mesenchymal phenotype. This transformation has been described in different lung diseases, such as lung cancer, interstitial lung diseases, asthma, chronic obstructive pulmonary disease and other muco-obstructive lung diseases, such as cystic fibrosis and non-cystic fibrosis bronchiectasis. The exaggerated chronic inflammation typical of these pulmonary diseases can induce molecular reprogramming with subsequent self-sustaining aberrant and excessive profibrotic tissue repair. Over time this process leads to structural changes with progressive organ dysfunction and lung function impairment. Although having common signalling pathways, specific triggers and regulation mechanisms might be present in each disease. This review aims to describe the various mechanisms associated with fibrotic changes and airway remodelling involved in chronic airway diseases. Having better knowledge of the mechanisms underlying the EMT process may help us to identify specific targets and thus lead to the development of novel therapeutic strategies to prevent or limit the onset of irreversible structural changes.

Roles of the HIF-1α pathway in the development and progression of keloids

Keloids, a pathological scar that is induced by the consequence of aberrant wound healing, is still a major global health concern for its unsatisfactory treatment outcomes. HIF-1α, a main regulator of hypoxia, mainly acts through some proteins or signaling pathways and plays important roles in a variety of biological processes. Accumulating evidence has shown that HIF-1α played a crucial role in the process of keloid formation. In this review, we attempted to summarize the current knowledge on the association between HIF-1α expression and the development and progression of keloids. Through a comprehensive analysis, the molecular mechanisms underlying HIF-1α in keloids were shown to be correlated to the proliferation of fibroblasts, angiogenesis, and collagen deposits. The affected proteins and the signaling pathways were multiple. For instance, HIF-1α was reported to promote keloids formation by enhancing angiogenesis, fibroblast proliferation, and collagen deposition through the activation of periostin PI3K/Akt, TGF-β/Smad and TLR4/MyD88/NF-κB pathway. However, the specific effects of HIF-1α on keloids keloid illnesses in clinical practice is are entirely unclear, and further studies in clinical trials are still warranted. Therefore, an in-depth understanding of the biological mechanisms of HIF-1α in keloid formation is significant to develop promising therapeutic targets for the treatment of keloids in clinical practice.

Kidney Damage in Long COVID: Studies in Experimental Mice

Signs and symptoms involving multiple organ systems which persist for weeks or months to years after the initial SARS-CoV-2 infection (also known as PASC or long COVID) are common complications of individuals with COVID-19. We recently reported pathophysiological changes in various organs post-acute infection of mice with mouse hepatitis virus-1 (MHV-1, a coronavirus) (7 days) and after long-term post-infection (12 months). One of the organs severely affected in this animal model is the kidney, which correlated well with human studies showing kidney injury post-SARS-CoV-2 infection. Our long-term post-infection pathological observation in kidneys includes the development of edema and inflammation of the renal parenchyma, severe acute tubular necrosis, and infiltration of macrophages and lymphocytes, in addition to changes observed in both acute and long-term post-infection, which include tubular epithelial cell degenerative changes, peritubular vessel congestion, proximal and distal tubular necrosis, hemorrhage in the interstitial tissue, and vacuolation of renal tubules. These findings strongly suggest the possible development of renal fibrosis, in particular in the long-term post-infection. Accordingly, we investigated whether the signaling system that is known to initiate the above-mentioned changes in kidneys in other conditions is also activated in long-term post-MHV-1 infection. We found increased TGF-β1, FGF23, NGAL, IL-18, HIF1-α, TLR2, YKL-40, and B2M mRNA levels in long-term post-MHV-1 infection, but not EGFR, TNFR1, BCL3, and WFDC2. However, only neutrophil gelatinase-associated lipocalin (NGAL) increased in acute infection (7 days). Immunoblot studies showed an elevation in protein levels of HIF1-α, TLR-2, and EGFR in long-term post-MHV-1 infection, while KIM-1 and MMP-7 protein levels are increased in acute infection. Treatment with a synthetic peptide, SPIKENET (SPK), which inhibits spike protein binding, reduced NGAL mRNA in acute infection, and decreased TGF-β1, BCL3 mRNA, EGFR, HIF1-α, and TLR-2 protein levels long-term post-MHV-1 infection. These findings suggest that fibrotic events may initiate early in SARS-CoV-2 infection, leading to pronounced kidney fibrosis in long COVID. Targeting these factors therapeutically may prevent acute or long-COVID-associated kidney complications.

The macrocyclic lactone oxacyclododecindione reduces fibrosis progression

Background: Renal fibrosis is one of the most important triggers of chronic kidney disease (CKD), and only a very limited number of therapeutic options are available to stop fibrosis progression. As fibrosis is characterized by inflammation, myofibroblast activation, and extracellular matrix (ECM) deposition, a drug that can address all these processes might be an interesting therapeutic option. Methods: We tested in vivo in an ischemia-reperfusion (I/R) model in C57BL/6 mice and in kidney tubular epithelial cells (TEC) (HK2 cell line and primary cells) whether the natural product oxacyclododecindione (Oxa) reduces fibrosis progression in kidney disease. This was evaluated by Western blot, mRNA expression, and mass spectrometry secretome analyses, as well as by immunohistochemistry. Results: Indeed, Oxa blocked the expression of epithelial-mesenchymal transition marker proteins and reduced renal damage, immune cell infiltration, and collagen expression and deposition, both in vivo and in vitro. Remarkably, the beneficial effects of Oxa were also detected when the natural product was administered at a time point of established fibrotic changes, a situation close to the clinical situation. Initial in vitro experiments demonstrated that a synthetic Oxa derivative possesses similar features. Conclusion: Although open questions such as possible side effects need to be investigated, our results indicate that the combination of anti-inflammatory and anti-fibrotic effects of Oxa make the substance a promising candidate for a new therapeutic approach in fibrosis treatment, and thus in the prevention of kidney disease progression.

Network pharmacology combined with molecular docking and experimental validation to reveal the pharmacological mechanism of naringin against renal fibrosis

To explore the pharmacological mechanism of naringin (NRG) in renal fibrosis (RF) based on network pharmacology combined with molecular docking and experimental validation. We used databases to screen for the targets of NRG and RF. The "drug-disease network" was established using Cytoscape. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of targets were performed using Metascape, and molecular docking was performed using Schrödinger. We established an RF model in both mice and cells to validate the results of network pharmacology. After screening the database, we identified 222 common targets of NRG and RF and established a target network. Molecular docking showed that the target AKT had a good interaction with NRG. We found that the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway was enriched by multiple targets and served as a target for experimental validation through GO and KEGG. The results revealed that NRG ameliorated renal dysfunction, reduced the release of inflammatory cytokines, decreased the expression of α-SMA, collagen I, and Fn, and recovered the expression of E-cad by inhibiting the PI3K/AKT signaling pathway. Our study used pharmacological analysis to predict the targets and mechanisms of NRG against RF. Furthermore, experiments proved that NRG inhibited RF effectively by targeting the PI3K/AKT signaling pathway.