Protein tyrosine phosphatase 1B regulates fibroblasts proliferation, motility and extracellular matrix synthesis via the MAPK/ERK signalling pathway in keloid

EEPD1 regulates inflammation and endothelial apoptosis in atherosclerosis through KLF4-EEPD1-ERK axis

BACKGROUND

Inflammation and endothelial apoptosis are implicated in the advancement of atherosclerosis. EEPD1 holds a pivotal position in the repair of DNA damage and contributes to the progression of multiple cancers. However, the role of EEPD1 in cardiovascular diseases needs to be explored further, especially in atherosclerosis.

METHODS

We constructed EEPD1 and ApoE (apolipoprotein E)-deficient mice to assess how EEPD1 influences endothelial inflammation and apoptosis within atherosclerotic plaques. High-throughput RNA sequencing of human aortic endothelial cell groups treated with siCon+TNFα and siEEPD1+TNFα identified notable disparities in the MAPK pathway between groups. Chromatin immunoprecipitation and luciferase reporter assay confirmed that KLF4 directly regulates EEPD1.

RESULTS

Further examination of gene expression data revealed elevated EEPD1 concentrations in atherosclerotic plaques of patients, which findings were corroborated in the aortas of ApoE-/- mice. Present study demonstrated that adhesion molecule expression, endothelial apoptosis, aortic root plaques and macrophage accumulation were markedly ameliorated in EEPD1-/-ApoE-/- mice compared to WT ApoE-/- mice. Functional analysis revealed that increase in EEPD1 promotes ERK phosphorylation and significantly increases endothelial apoptosis and inflammation in atherosclerosis, which was abrogated by inhibition of ERK phosphorylation. We found KLF4 to be the transcription repressor of EEPD1 through luciferase assay and chromatin immunoprecipitation, and KLF4 inhibition abrogated the amelioration of endothelial apoptosis and inflammation caused by EEPD1 deletion.

CONCLUSIONS

Collectively, this study revealed that EEPD1 deletion can lead to amelioration of atherosclerosis through the KLF4-EEPD1-ERK axis. Hence, targeting EEPD1 could be a promising therapeutic strategy for patients with atherosclerosis.

Astragalin inhibits fibroblast proliferation, motion, and ECM synthesis and regulates the MAPK pathway in keloid

Keloid is a fibroproliferative skin disorder characterized by fibroblast hyperproliferation and excessive extracellular matrix (ECM) deposition. Astragalin (AST) is a bioactive natural flavonoid with multiple pharmacological properties. This study aims to investigate the effect of AST on keloid formation in vitro. Primary keloid fibroblasts (KFs) and normal fibroblasts (NFs) were isolated from human keloid tissues and normal skin tissues, respectively, and treated with or without AST. MTT, colony formation, and Transwell assays were utilized to evaluate AST's effect on fibroblast proliferation, migration, and invasiveness. Western blotting was implemented for detecting protein levels of ECM components and mitogen-activated protein kinases (MAPKs). The results showed that AST treatment hindered the proliferative, migratory, and invasive capacities of KFs and NFs, and KFs were more sensitive to AST than NFs. AST restrained ECM deposition and inactivated the MAPK signaling pathway in KFs and NFs. In conclusion, AST suppresses the invasive growth of keloid fibroblasts probably by inactivating MAPK signaling.

Orthogonal upconversion nanocarriers for combined photodynamic therapy and precisely triggered gene silencing in combating keloids

Keloids are pathological scars characterized by excessive fibroblast proliferation, abnormal collagen deposition, and chronic inflammation, which often result in high recurrence rates and limited treatment success. Targeting BACH1 with gene therapy has shown promise in regulating fibroblast activity and reducing inflammation. However, effective delivery systems for targeted gene therapy in keloids remain a major challenge. Here, we develop a novel nanocarrier platform based on orthogonal upconversion nanoparticles (OUNCs) to achieve spatiotemporal silencing of BACH1 and combined photodynamic therapy (PDT). The OUNCs are composed of orthogonal upconversion nanoparticles (UCNPs), photosensitizer (Rose Bengal), ROS-sensitive diselenide bonds (SeSe), therapeutic siBACH1, and an active targeting moiety (hyaluronic acid) to specifically target keloid fibroblasts (KFs). We demonstrate that the OUNCs can effectively induce KFs apoptosis, inhibit KFs proliferation, and reduce M2 macrophages recruitment by modulating the Rap1/MEK/ERK signaling pathway. Our study represents a breakthrough in precision therapy for keloids, providing a promising platform that integrates siBACH1-based gene therapy with NIR light-triggered PDT.

Comprehensive Insights into Keloid Pathogenesis and Advanced Therapeutic Strategies

Keloid scars, characterized by abnormal fibroproliferation and excessive extracellular matrix (ECM) production that extends beyond the original wound, often cause pruritus, pain, and hyperpigmentation, significantly impacting the quality of life. Keloid pathogenesis is multifactorial, involving genetic predisposition, immune response dysregulation, and aberrant wound-healing processes. Central molecular pathways such as TGF-β/Smad and JAK/STAT are important in keloid formation by sustaining fibroblast activation and ECM deposition. Conventional treatments, including surgical excision, radiation, laser therapies, and intralesional injections, yield variable success but are limited by high recurrence rates and potential adverse effects. Emerging therapies targeting specific immune pathways, small molecule inhibitors, RNA interference, and mesenchymal stem cells show promise in disrupting the underlying mechanisms of keloid pathogenesis, potentially offering more effective and lasting treatment outcomes. Despite advancements, further research is essential to fully elucidate the precise mechanisms of keloid formation and to develop targeted therapies. Ongoing clinical trials and research efforts are vital for translating these scientific insights into practical treatments that can markedly enhance the quality of life for individuals affected by keloid scars.

Identification of novel immune-related signatures for keloid diagnosis and treatment: insights from integrated bulk RNA-seq and scRNA-seq analysis

BACKGROUND

Keloid is a disease characterized by proliferation of fibrous tissue after the healing of skin tissue, which seriously affects the daily life of patients. However, the clinical treatment of keloids still has limitations, that is, it is not effective in controlling keloids, resulting in a high recurrence rate. Thus, it is urgent to identify new signatures to improve the diagnosis and treatment of keloids.

METHOD

Bulk RNA seq and scRNA seq data were downloaded from the GEO database. First, we used WGCNA and MEGENA to co-identify keloid/immune-related DEGs. Subsequently, we used three machine learning algorithms (Randomforest, SVM-RFE, and LASSO) to identify hub immune-related genes of keloid (KHIGs) and investigated the heterogeneous expression of KHIGs during fibroblast subpopulation differentiation using scRNA-seq. Finally, we used HE and Masson staining, quantitative reverse transcription-PCR, western blotting, immunohistochemical, and Immunofluorescent assay to investigate the dysregulated expression and the mechanism of retinoic acid in keloids.

RESULTS

In the present study, we identified PTGFR, RBP5, and LIF as KHIGs and validated their diagnostic performance. Subsequently, we constructed a novel artificial neural network molecular diagnostic model based on the transcriptome pattern of KHIGs, which is expected to break through the current dilemma faced by molecular diagnosis of keloids in the clinic. Meanwhile, the constructed IG score can also effectively predict keloid risk, which provides a new strategy for keloid prevention. Additionally, we observed that KHIGs were also heterogeneously expressed in the constructed differentiation trajectories of fibroblast subtypes, which may affect the differentiation of fibroblast subtypes and thus lead to dysregulation of the immune microenvironment in keloids. Finally, we found that retinoic acid may treat or alleviate keloids by inhibiting RBP5 to differentiate pro-inflammatory fibroblasts (PIF) to mesenchymal fibroblasts (MF), which further reduces collagen secretion.

CONCLUSION

In summary, the present study provides novel immune signatures (PTGFR, RBP5, and LIF) for keloid diagnosis and treatment, and identifies retinoic acid as potential anti-keloid drugs. More importantly, we provide a new perspective for understanding the interactions between different fibroblast subtypes in keloids and the remodeling of their immune microenvironment.

Therapeutic potential and pharmacological mechanism of visnagin

Visnagin is a furanochromone and one of the most important compound in the Ammi visnaga (L.) Lam (a synonym of Visnaga daucoides Gaertn.) plant, which is used to cure various ailments. Many investigations into the bioactive properties of visnagin have been studied to date. The literature on visnagin demonstrates its biological properties, including anti-inflammatory, anti-diabetic, and beneficial effects in cardiovascular and renal diseases. Moreover, visnagin improves sperm quality parameters, stimulates steroidogenesis, and increases serum gonadotropins and testosterone levels, while decreasing pro-inflammatory cytokines, oxidative damage, genomic instability, and it modulates apoptosis. Thus, visnagin has emerged as an exciting lead for further research, owing to its potential in various unmet clinical needs. The current review summarized its basic structure, pharmacokinetics, and pharmacological effects, focusing on its mechanisms of action. The review will help to understand the potential of visnagin as an alternative treatment strategy for several diseases and provide insight into research topics that need further exploration for visnagin's safe clinical use. Please cite this article as: Yadav P, Singh SK, Datta S, Verma S, Verma A, Rakshit A, Bali A, Bhatti JS, Khurana A, Navik U. Therapeutic potential and pharmacological mechanism of visnagin. J Integr Med. 2024; 22(4): 399-412.

The PTP1B Inhibitor Trodusquemine (MSI-1436) Improves Glucose Uptake in Equine Metabolic Syndrome Affected Liver through Anti-Inflammatory and Antifibrotic Activity

Background

Hyperactivation of protein tyrosine phosphatase (PTP1B) has been associated with several metabolic malfunctions ranging from insulin resistance, metaflammation, lipotoxicity, and hyperglycaemia. Liver metabolism failure has been proposed as a core element in underlying endocrine disorders through persistent inflammation and highly fibrotic phenotype.

Methods

In this study, the outcomes of PTP1B inhibition using trodusquemine (MSI-1436) on key equine metabolic syndrome (EMS)-related alterations including inflammation, fibrosis, and glucose uptake have been analyzed in liver explants collected from EMS-affected horses using various analytical techniques, namely, flow cytometry, RT-qPCR, and Western blot.

Results

PTP1B inhibition using trodusquemine resulted in decreased proinflammatory cytokines (IL-1β, TNF-α, and IL-6) release from liver and PBMC affected by EMS and regulated expression of major proinflammatory microRNAs such as miR-802 and miR-211. Moreover, MSI-1436 enhanced the anti-inflammatory profile of livers by elevating the expression of IL-10 and IL-4 and activating CD4+CD25+Foxp3+ regulatory T cells in treated PBMC. Similarly, the inhibitor attenuated fibrogenic pathways in the liver by downregulating TGF-β/NOX1/4 axis and associated MMP-2/9 overactivation. Interestingly, PTP1B inhibition ameliorated the expression of TIMP-1 and Smad7, both important antifibrotic mediators. Furthermore, application of MSI-1436 was found to augment the abundance of glycosylated Glut-2, which subsequently expanded the glucose absorption in the EMS liver, probably due to an enhanced Glut-2 stability and half-life onto the plasma cell membranes.

Conclusion

Taken together, the presented data suggest that the PTP1B inhibition strategy and the use of its specific inhibitor MSI-1436 represents a promising option for the improvement of liver tissue integrity and homeostasis in the course of EMS and adds more insights for ongoing clinical trials for human MetS management.

Role of Protein Tyrosine Phosphatase 1B Inhibitor in Early Brain Injury of Subarachnoid Hemorrhage in Mice

Clinically, early brain injury (EBI), which refers to the acute injuries to the whole brain in the phase of the first 72 h following subarachnoid hemorrhage (SAH), is intensely investigated to improve neurological and psychological function. Additionally, it will be meaningful to explore new therapeutic approaches for EBI treatment to improve the prognosis of patients with SAH. To investigate the underlying neuroprotection mechanism in vitro, the Protein tyrosine phosphatase 1B inhibitor (PTP1B-IN-1) was put in primary neurons induced by OxyHb to observe neuroapoptosis, neuroinflammation, and ER stress. Then, one hundred forty male mice were subjected to Experiment two and Experiment three. The mice in the SAH24h + PTP1B-IN-1 group were given an intraperitoneal injection of 5 mg/kg PTP1B-IN-1 30 min before anesthesia. SAH grade, neurological score, brain water content, Western blot, PCR, and Transmission Electron Microscopy (TEM) were performed to observe the underlying neuroprotection mechanism in vivo. Overall, this study suggests that PTP1B-IN-1 could ameliorate neuroapoptosis, neuroinflammation, and ER stress in vitro and in vivo by regulating the IRS-2/AKT signaling pathway, suggesting that PTP1B-IN-1 may be a candidate drug for the treatment of early brain injury after SAH.

Repair of degenerative nucleus pulposus by polyphenol nanosphere-encapsulated hydrogel gene delivery system

Intervertebral disc degeneration (IDD) progresses due to local inflammatory response, gradually unbalanced anabolic/catabolic activity, and progressive functional impairment within the nucleus pulposus. Antagomir-21, a cholesterol-modified miRNA-21 inhibitor, has potential extracellular matrix (ECM) regenerative ability, but its application for IDD is limited by inadequate local delivery systems. An injectable hydrogel gene delivery system encapsulating a modified tannic acid nanoparticles (TA NPs) vector was engineered for on-demand and sustained delivery of antagomir-21 into the nucleus pulposus. After nucleus pulposus cell uptake, antagomir-21 was released from TA NPs and regulated the ECM metabolic balance by inhibiting the MAPK/ERK signaling pathway. TA NPs scavenged intracellular ROS and reduced inflammation by downregulating TNF-α expression. In vivo, synergistic anti-inflammatory effects and ECM regeneration effectively promoted therapeutic efficacy against IDD. This hydrogel gene delivery system represents a creative, promising strategy for IDD repair.

Novel Genes Potentially Involved in Fibroblasts of Diabetic Wound

Fibroblasts are the essential cell type of skin, highly involved in the wound regeneration process. In this study, we sought to screen out the novel genes which act important roles in diabetic fibroblasts through bioinformatic methods. A total of 811 and 490 differentially expressed genes (DEGs) between diabetic and normal fibroblasts were screened out in GSE49566 and GSE78891, respectively. Furthermore, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways involved in type 2 diabetes were retrieved from miRWalk. Consequently, the integrated bioinformatic analyses revealed the shared KEGG pathways between DEG-identified and diabetes-related pathways were functionally enriched in the MAPK signaling pathway, and the MAPKAPK3, HSPA2, TGFBR1, and p53 signaling pathways were involved. Finally, ETV4 and NPE2 were identified as the targeted transcript factors of MAPKAPK3, HSPA2, and TGFBR1. Our findings may throw novel sight in elucidating the molecular mechanisms of fibroblast pathologies in patients with diabetic wounds and targeting new factors to advance diabetic wound treatment in clinic.