Abrogation of transforming growth factor-β-induced tissue fibrosis in TBRIcaCol1a2Cre transgenic mice by the second generation tyrosine kinase inhibitor SKI-606 (Bosutinib)

Cluster of differentiation molecules in the metabolic syndrome

Metabolic syndrome (MetS) represents a significant public health concern due to its association with an increased risk of cardiovascular disease, type 2 diabetes, and other serious health conditions. Despite extensive research, the underlying molecular mechanisms contributing to MetS pathogenesis remain elusive. This review aims to provide a comprehensive overview of the molecular mechanisms linking MetS and cluster of differentiation (CD) markers, which play critical roles in immune regulation and cellular signaling. Through an extensive literature review with a systematic approach, we examine the involvement of various CD markers in MetS development and progression, including their roles in adipose tissue inflammation, insulin resistance, dyslipidemia, and hypertension. Additionally, we discuss potential therapeutic strategies targeting CD markers for the management of MetS. By synthesizing current evidence, this review contributes to a deeper understanding of the complex interplay between immune dysregulation and metabolic dysfunction in MetS, paving the way for the development of novel therapeutic interventions.

Emerging opportunities to treat idiopathic pulmonary fibrosis: Design, discovery, and optimizations of small-molecule drugs targeting fibrogenic pathways

Idiopathic pulmonary fibrosis (IPF) is the most common fibrotic form of idiopathic diffuse lung disease. Due to limited treatment options, IPF patients suffer from poor survival. About ten years ago, Pirfenidone (Shionogi, 2008; InterMune, 2011) and Nintedanib (Boehringer Ingelheim, 2014) were approved, greatly changing the direction of IPF drug design. However, limited efficacy and side effects indicate that neither can reverse the process of IPF. With insights into the occurrence of IPF, novel targets and agents have been proposed, which have fundamentally changed the treatment of IPF. With the next-generation agents, targeting pro-fibrotic pathways in the epithelial-injury model offers a promising approach. Besides, several next-generation IPF drugs have entered phase II/III clinical trials with encouraging results. Due to the rising IPF treatment requirements, there is an urgent need to completely summarize the mechanisms, targets, problems, and drug design strategies over the past ten years. In this review, we summarize known mechanisms, target types, drug design, and novel technologies of IPF drug discovery, aiming to provide insights into the future development and clinical application of next-generation IPF drugs.

New therapeutic approaches against pulmonary fibrosis

Pulmonary fibrosis is the end-stage change of a large class of lung diseases characterized by the proliferation of fibroblasts and the accumulation of a large amount of extracellular matrix, accompanied by inflammatory damage and tissue structure destruction, which also shows the normal alveolar tissue is damaged and then abnormally repaired resulting in structural abnormalities (scarring). Pulmonary fibrosis has a serious impact on the respiratory function of the human body, and the clinical manifestation is progressive dyspnea. The incidence of pulmonary fibrosis-related diseases is increasing year by year, and no curative drugs have appeared so far. Nevertheless, research on pulmonary fibrosis have also increased in recent years, but there are no breakthrough results. Pathological changes of pulmonary fibrosis appear in the lungs of patients with coronavirus disease 2019 (COVID-19) that have not yet ended, and whether to improve the condition of patients with COVID-19 by means of the anti-fibrosis therapy, which are the questions we need to address now. This review systematically sheds light on the current state of research on fibrosis from multiple perspectives, hoping to provide some references for design and optimization of subsequent drugs and the selection of anti-fibrosis treatment plans and strategies.

Oral Targeted Delivery of Imatinib by pH Responsive Copolymer Modulates Liver Fibrosis in the Mice Model

Liver fibrosis is a significant cause of morbidity and mortality without approved treatment. The therapeutic effects of Imatinib as a tyrosine kinase inhibitor on reversing liver fibrosis have already been shown. However, considering the conventional route of Imatinib administration, the amount of drug to be used is very high, and its side effects are raised. Therefore, we designed an efficient pH-sensitive polymer for the targeted delivery of Imatinib in treating a carbon tetrachloride (CCl4)-induced liver fibrosis. This nanotherapeutic system-based Vitamin A (VA)-modified Imatinib-loaded poly (lactic-co-glycolic acid)/Eudragit S100 (PLGA-ES100) has been successfully fabricated by adapting the solvent evaporation technique. The applying ES100 on the surface of our desired nanoparticles (NPs) protects drug release at the acidic pH of the gastric and guarantees the effective release of Imatinib at a higher pH of the intestine. Besides, VA-functionalized NPs could be an ideal efficient drug delivery system due to the high capacity of hepatic cell lines to absorb VA. For induction of liver fibrosis, CCL4 was intraperitoneally (IP) injected twice a week for six weeks in BALB/c mice. Oral administration of VA-targeted PLGA-ES100 NPs loaded with Rhodamine Red™ by live animal imaging showed a preferential accumulation of the selected NPs in the liver of mice. Besides, administrating targeted Imatinib-loaded NPs significantly decreased serum levels of ALT, and AST, and also reduced the expression of extracellular matrix components, including collagen I, collagen III, and α-SMA, considerably. Interestingly, histopathological evaluation of liver tissues through H&E and Masson's trichrome staining showed that oral administration of targeted Imatinib-loaded NPs reduced hepatic damage by enhancing hepatic structure condition. Also, the Sirius-red staining indicated a reduction in collagen expression during treatment with targeted NP containing Imatinib. The immunohistochemistry result on liver tissue shows a significant decrease in the expression of α-SMA in groups treated with targeted NP. In the meantime, administration of a very scarce dose of Imatinib via targeted NP caused a substantial decline in the expression of fibrosis marker genes (Collagen I, Collagen III, α-SMA). Our results confirmed that novel pH-sensitive VA-targeted PLGA-ES100 NPs could efficiently deliver Imatinib to the liver cells. Loading Imatinib in the PLGA-ES100/VA might overcome many challenges facing conventional Imatinib therapy, including gastrointestinal pH, the low concentration at the target region, and toxicity.

Imatinib Attenuates Pentylenetetrazole Kindled and Pilocarpine Induced Recurrent Spontaneous Seizures in Mice

c-Abl is a non-receptor tyrosine kinase that promotes intracellular apoptotic signaling in prolonged epileptic seizures. PTZ and pilocarpine-induced continuous epileptic convulsions cause neuronal death and gliosis. C-Abl is linked to oxidative stress, neuronal hyperexcitability, mitochondrial malfunction, and subsequent seizures. We investigated the involvement of c-Abl in epileptogenesis by employing its selective inhibitor Imatinib (1 & 3 mg/kg; i.p.) together with conventional medication valproate (110 mg/kg; i.p.) tends to be effective in decreasing seizures threshold provoked by PTZ for 15 days and pilocarpine for 37 days. Further, Imatinib was effective in preventing epileptic seizures arbitrated oxidative stress injury. Oxidative stress has been linked to excitotoxicity that is considered to pathogenic factor in epileptic brain damage. As ELIZA and biochemical estimations showed the high level of c-Abl as an indicator of neuronal oxidative and apoptosis under chronic PTZ & pilocarpine epileptic seizures marked by decreased antioxidants and elevated levels of caspase-3 that were successfully prevented with Imatinib treatment same as valproate (standard drug). Further, the aberrant c-Abl activation is also linked with neuroinflammation that is also predisposing factor in the development of seizures. Selective inhibition of c-Abl by Imatinib also showed anti-inflammatory activity marked with suppressed levels of NF-kB and pro-inflammatory mediators (TNF-alpha, IL-1β, and IL-6) suggesting the neuroprotective effect of Imatinib same as valproate (standard drug) in epilepsy. Therefore, the current study provides preclinical evidence of Imatinib as a potential treatment for seizures, as well as an understanding of potential role of c-Ablin epilepsy.

Genetic Disruption of Guanylyl Cyclase/Natriuretic Peptide Receptor-A Triggers Differential Cardiac Fibrosis and Disorders in Male and Female Mutant Mice: Role of TGF-β1/SMAD Signaling Pathway

The global targeted disruption of the natriuretic peptide receptor-A (NPRA) gene (Npr1) in mice provokes hypertension and cardiovascular dysfunction. The objective of this study was to determine the mechanisms regulating the development of cardiac fibrosis and dysfunction in Npr1 mutant mice. Npr1 knockout (Npr1^-/-, 0-copy), heterozygous (Npr1^+/-, 1-copy), and wild-type (Npr1^+/+, 2-copy) mice were treated with the transforming growth factor (TGF)-β1 receptor (TGF-β1R) antagonist GW788388 (2 µg/g body weight/day; ip) for 28 days. Hearts were isolated and used for real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blot, and immunohistochemical analyses. The Npr1^-/- (0-copy) mice showed a 6-fold induction of cardiac fibrosis and dysfunction with markedly induced expressions of collagen-1α (3.8-fold), monocyte chemoattractant protein (3.7-fold), connective tissue growth factor (CTGF, 5.3-fold), α-smooth muscle actin (α-SMA, 6.1-fold), TGF-βRI (4.3-fold), TGF-βRII (4.7-fold), and phosphorylated small mothers against decapentaplegic (pSMAD) proteins, including pSMAD-2 (3.2-fold) and pSMAD-3 (3.7-fold), compared with wild-type mice. The expressions of phosphorylated extracellular-regulated kinase ERK1/2 (pERK1/2), matrix metalloproteinases-2, -9, (MMP-2, -9), and proliferating cell nuclear antigen (PCNA) were also significantly upregulated in Npr1 0-copy mice. The treatment of mutant mice with GW788388 significantly blocked the expression of fibrotic markers, SMAD proteins, MMPs, and PCNA compared with the vehicle-treated control mice. The treatment with GW788388 significantly prevented cardiac dysfunctions in a sex-dependent manner in Npr1 0-copy and 1-copy mutant mice. The results suggest that the development of cardiac fibrosis and dysfunction in mutant mice is predominantly regulated through the TGF-β1-mediated SMAD-dependent pathway.

New Insights into Profibrotic Myofibroblast Formation in Systemic Sclerosis: When the Vascular Wall Becomes the Enemy

In systemic sclerosis (SSc), abnormalities in microvessel morphology occur early and evolve into a distinctive vasculopathy that relentlessly advances in parallel with the development of tissue fibrosis orchestrated by myofibroblasts in nearly all affected organs. Our knowledge of the cellular and molecular mechanisms underlying such a unique relationship between SSc-related vasculopathy and fibrosis has profoundly changed over the last few years. Indeed, increasing evidence has suggested that endothelial-to-mesenchymal transition (EndoMT), a process in which profibrotic myofibroblasts originate from endothelial cells, may take center stage in SSc pathogenesis. While in arterioles and small arteries EndoMT may lead to the accumulation of myofibroblasts within the vessel wall and development of fibroproliferative vascular lesions, in capillary vessels it may instead result in vascular destruction and formation of myofibroblasts that migrate into the perivascular space with consequent tissue fibrosis and microvessel rarefaction, which are hallmarks of SSc. Besides endothelial cells, other vascular wall-resident cells, such as pericytes and vascular smooth muscle cells, may acquire a myofibroblast-like synthetic phenotype contributing to both SSc-related vascular dysfunction and fibrosis. A deeper understanding of the mechanisms underlying the differentiation of myofibroblasts inside the vessel wall provides the rationale for novel targeted therapeutic strategies for the treatment of SSc.

The Role of Pro-fibrotic Myofibroblasts in Systemic Sclerosis: from Origin to Therapeutic Targeting

Systemic sclerosis (SSc, scleroderma) is a complex connective tissue disorder characterized by multisystem clinical manifestations resulting from immune dysregulation/autoimmunity, vasculopathy and, most notably, progressive fibrosis of the skin and internal organs. In recent years, it has emerged that the main drivers of SSc-related tissue fibrosis are myofibroblasts, a type of mesenchymal cells with both the extracellular matrix-synthesizing features of fibroblasts and the cytoskeletal characteristics of contractile smooth muscle cells. The accumulation and persistent activation of pro-fibrotic myofibroblasts during SSc development and progression result into elevated mechanical stress and reduced matrix plasticity within the affected tissues and may be ascribed to a reduced susceptibility of these cells to pro-apoptotic stimuli, as well as their increased formation from tissue-resident fibroblasts or transition from different cell types. Given the crucial role of myofibroblasts in SSc pathogenesis, finding the way to inhibit myofibroblast differentiation and accumulation by targeting their formation, function and survival may represent an effective approach to hamper the fibrotic process or even halt or reverse established fibrosis. In this review, we discuss the role of myofibroblasts in SSc-related fibrosis, with a special focus on their cellular origin and the signaling pathways implicated in their formation and persistent activation. Furthermore, we provide an overview of potential therapeutic strategies targeting myofibroblasts that may be able to counteract fibrosis in this pathological condition.

Repurposing of Kinase Inhibitors for Treatment of COVID-19

The outbreak of COVID-19, the pandemic disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spurred an intense search for treatments by the scientific community. In the absence of a vaccine, the goal is to target the viral life cycle and alleviate the lung-damaging symptoms of infection, which can be life-threatening. There are numerous protein kinases associated with these processes that can be inhibited by FDA-approved drugs, the repurposing of which presents an alluring option as they have been thoroughly vetted for safety and are more readily available for treatment of patients and testing in clinical trials. Here, we characterize more than 30 approved kinase inhibitors in terms of their antiviral potential, due to their measured potency against key kinases required for viral entry, metabolism, or reproduction. We also highlight inhibitors with potential to reverse pulmonary insufficiency because of their anti-inflammatory activity, cytokine suppression, or antifibrotic activity. Certain agents are projected to be dual-purpose drugs in terms of antiviral activity and alleviation of disease symptoms, however drug combination is also an option for inhibitors with optimal pharmacokinetic properties that allow safe and efficacious co-administration with other drugs, such as antiviral agents, IL-6 blocking agents, or other kinase inhibitors.

Src family kinases and pulmonary fibrosis: A review

Src family kinases (SFKs) is a non-receptor protein tyrosine kinases family. They are crucial in signal transduction and regulation of various cell biological processes, such as proliferation, differentiation and apoptosis. The role and mechanism of SFKs in tumorigenesis have been widely studied. However, more and more studies have also shown that SFKs are involved in the pathogenesis of pulmonary fibrosis (PF). Myofibroblasts activation, epithelial-mesenchymal transition and inflammation response are three pivotal pathomechanisms in the development of pulmonary fibrotic disease. In this article, we summarize the roles of SFKs in these biological processes. SFKs play a crucial role in the pathogenesis of PF, making it a promising molecular target for the treatment of these diseases. We will pay special attention to the role of SFKs in idiopathic pulmonary fibrosis (IPF), and also emphasize the important findings in other pulmonary fibrotic diseases because their pathological mechanisms are similar. We will then describe the translation results obtained with SFKs inhibitors in basic and clinical studies.

Therapeutic molecular targets of SSc-ILD

Systemic sclerosis is a fibrosing chronic connective tissue disease of unknown etiology. A major hallmark of systemic sclerosis is the uncontrolled and persistent activation of fibroblasts, which release excessive amounts of extracellular matrix, lead to organ dysfunction, and cause high mobility and motility of patients. Systemic sclerosis–associated interstitial lung disease is one of the most common fibrotic organ manifestations in systemic sclerosis and a major cause of death. Treatment options for systemic sclerosis–associated interstitial lung disease and other fibrotic manifestations, however, remain very limited. Thus, there is a huge medical need for effective therapies that target tissue fibrosis, vascular alterations, inflammation, and autoimmune disease in systemic sclerosis–associated interstitial lung disease. In this review, we discuss data suggesting therapeutic ways to target different genes in distinct tissues/organs that contribute to the development of SSc.

Insights into myofibroblasts and their activation in scleroderma: opportunities for therapy?

PURPOSE OF REVIEW

The persistence of myofibroblasts is a key feature of fibrosis and in fibrotic diseases including scleroderma. This review evaluates the emerging concepts of the origins and cell populations that contribute to myofibroblasts and the molecular mechanisms that govern phenotypic conversion and that highlight opportunities for new interventional treatments in scleroderma.

RECENT FINDINGS

Studies have defined heterogeneity in fibroblast-like cells that can develop into myofibroblast in normal wound healing, scarring and fibrosis. Characterizing these distinct cell populations and their behaviour has been a key focus. In addition, the overarching impact of epigenetic regulation of genes associated with inflammatory responses, cell signalling and cell communication and the extracellular matrix (ECM) has provided important insights into the formation of myofibroblast and their function. Important new studies include investigations into the relationship between inflammation and myofibroblast production and further evidence has been gathered that reveal the importance of ECM microenvironment, biomechanical sensing and mechanotransduction.

SUMMARY

This review highlights our current understanding and outlines the increasing complexity of the biological processes that leads to the appearance of the myofibroblast in normal functions and in diseased tissues. We also focus on areas of special interest in particular, studies that have therapeutic potential in fibrosis and scleroderma.

Systemic Sclerosis and Serum Content of Transforming Growth Factor

Systemic sclerosis is a connective tissue disease characterized by tissue fibrosis leading to interstitial lung disease. Transforming growth factor-β (TGF-β) has been of interest as a potential diagnostic marker and also as a drug target in systemic sclerosis. The aim of this study was to assess the serum content of TGF-β1 in patients with systemic sclerosis and to assess its potential role in tissue fibrosis. The study included 30 patients, 5 men and 25 women, of the mean age of 46.9 ± 12.8 years, diagnosed with systemic sclerosis. The control group consisted of 19 women of the mean age of 28.4 ± 7.8 years, diagnosed with primary Raynaud's disease. TGF-β1 serum levels were measured, chest imaging examinations were performed, and fibrotic tissue changes were assessed using the modified Rodnan Skin Score. We found that the mean serum TGF-β1 content in patients with systemic sclerosis was 598.7 ± 242.6 pg/mL, whereas it was 568.4 ± 322.2 pg/mL in the control group (p = 0.378). We also failed to substantiate any significant relationship between TGF-β1 serum levels and the severity of pulmonary and skin fibrosis in systemic sclerosis. In conclusion, systemic sclerosis does not seem a disease that would be accompanied by a specific enhancement of serum TGF-β1. Thus, this cytokine is rather unlikely to play an essential role in the development and course of the disease, nor can it be considered diagnostic or prognostic marker.