TGF-β1 Secretion Research Articles

Differential activity of MAPK signalling defines fibroblast subtypes in pancreatic cancer

Fibroblast heterogeneity is increasingly recognised across cancer conditions. Given their important contribution to disease progression, mapping fibroblasts’ heterogeneity is critical to devise effective anti-cancer therapies. Cancer-associated fibroblasts (CAFs) represent the most abundant cell population in pancreatic ductal adenocarcinoma (PDAC). Whether CAF phenotypes are differently specified by PDAC cell lineages remains to be elucidated. Here, we reveal an important role for the MAPK signalling pathway in defining PDAC CAF phenotypes. We show that epithelial MAPK activity promotes the myofibroblastic differentiation of CAFs by sustaining the expression and secretion of TGF-β1. We integrate single-cell profiling of post-perturbation transcriptional responses from mouse models with cellular and spatial profiles of human tissues to define a MAPKhigh CAF (mapCAF) phenotype. We show that this phenotype associates with basal-like tumour cells and reduced frequency of CD8+ T cells. In addition to elevated MAPK activity, this mapCAF phenotype is characterized by TGF-β signalling, hypoxia responsive signatures, and immunoregulatory gene programs. Furthermore, the mapCAF signature is enriched in myofibroblastic CAFs from various cancer conditions and correlates with reduced response to immune checkpoint inhibition in melanoma. Altogether, our data expand our knowledge on CAF phenotype heterogeneity and reveal a potential strategy for targeting myofibroblastic CAFs in vivo.

Cancer Cell-Derived Exosomal miR-500a-3p Modulates Hepatic Stellate Cell Activation and the Immunosuppressive Microenvironment.

Hepatocellular carcinoma (HCC) mainly depends on liver fibrosis/cirrhosis, which is regulated by tumor cells and the tumor microenvironment (TME), and is a crucial factor in tumor progression. This study aimed to identify abnormally expressed miR-500a-3p in the hepatitis-cirrhosis-HCC pathway and explored the roles of miR-500a-3p in HCC progression. A clinical cohort of patients with HCC is studied retrospectively. Subsequently, the role of miR-500a-3p transported by HCC exosomes in hepatic stellate cell (HSC) activation, hepatoma growth and invasion, and immune cell differentiation is determined by in vitro and in vivo experiments. In clinical tissues, miR-500a-3p is significantly enriched in HCC and cirrhosis tissues, and co-expression of the immune marker CD4 or PD-L1 significantly correlates with low survival rates in patients. Extracellular miR-500a-3p is taken up by HSC and PBMC, which promotes the secretion of the cytokines TGF-β1 and IL-10, increases PD-L1 expression in HSC, and stabilizes PD-1 expression in PBMC to affect the TME. Moreover, miR-500a-3p is associated with CD4+ T-cell exhaustion and Treg differentiation and is significantly associated with increased tumorigenicity in in situ mouse HCC models. Mechanistically, HCC-derived exosomal miR-500a-3p directly influences SOCS2 to regulate the JAK3/STAT5A/STAT5B signaling pathway. MiR-500a-3p promotes the growth and migration of HCC through the SOCS2/JAK3/STAT5A/STAT5B axis.

Proteoglycans Enhance the Therapeutic Effect of BMSC Transplantation on Osteoarthritis.

The injection of bone mesenchymal stem cells (BMSCs) for osteoarthritis (OA) treatment fails to address the disrupted extracellular microenvironment, limiting the differentiation and paracrine functions of BMSCs and resulting in suboptimal therapeutic outcomes. Proteoglycans (PGs) promote cell differentiation, tissue repair, and microenvironment remodeling. This study investigated the potential of combining PGs with BMSCs to increase the efficacy of OA treatment. We evaluated the effects of PG on BMSC and chondrocyte functions by adding various PG concentrations to the culture media. Additionally, a Transwell system was used to assess the impact of PG on the communication between BMSCs and chondrocytes. The results of the in vitro experiment were verified by tissue staining and immunohistochemistry following the treatment of OA model rats. Our findings indicate that PG effectively induces Col II expression in BMSCs and enhances the paracrine secretion of TGF-β1, thereby activating the TGF-β signaling pathway in chondrocytes and increasing PRG4 gene expression. Compared with the other groups, the BMSC/PG treatment group presented a smoother articular surface and more robust extracellular matrix than the other groups in vivo, with significantly increased expression and distribution of Smad2/3 and PRG4. PG enhances BMSC differentiation into chondrocytes and stimulates paracrine TGF-β1 secretion. Proteoglycans not only promote chondrocyte differentiation and paracrine TGF-β1 signaling in BMSCs but also increase the sensitivity of chondrocytes to TGF-β1 secreted from BMSCs, leading to PRG4 expression through the TGFR/Smad2/3 pathway. Proteoglycans can enhance the therapeutic effect of BMSC treatment on OA and have the potential to delay the degeneration of OA cartilage.

Harnessing β-glucan conjugated quercetin nanocomplex to function as a promising anti-inflammatory agent via macrophage-targeted delivery

Quercetin, a promising anti-inflammatory agent, faces challenges related to poor bioavailability and limited practical applications. β-glucan, a natural polysaccharide, can be specifically recognized by macrophages, making it an ideal targeting carrier to enhance therapeutic efficacy for macrophage-related dysfunctions. In this study, β-glucan conjugated quercetin nano-complexes (CM-Cur@QT) were developed to target macrophage and alleviate pro-inflammatory response in M1-like macrophages. The results demonstrated that CM-Cur@QT exhibited a spheric shape with an average diameter around 200 nm. FT-IR, 1H NMR, XRD and XPS analyses confirmed the complexation of CM-Cur@QT. This complex showed excellent stability during stimulated digestion, protecting QT from degradation while maintaining favorable antioxidant activity. After complexation, CM-Cur@QT displayed sustained uptake kinetics and enhanced accumulation in macrophages, with a 61.88 % increase compared to individual quercetin after 5 h of incubation. Meanwhile, CM-Cur@QT administration induced evidently cell cycle phases transitions and altered phagocytotic activity in M1-like macrophages. Furthermore, CM-Cur@QT reduced intracellular ROS accumulation, achieving a ROS scavenging rate of up to 49.92 %, compared to 25.59 % in quercetin group. This complex also effectively modulated TNF-a, IL-6 and TGF-β secretion profiles in pro-inflammatory macrophages, outperforming individual QT treatment. Notably, CM-Cur@QT facilitated anti-inflammatory effects while minimizing impacts on inactivated M0 macrophages. These findings underscore the potential of CM-Cur@QT as a promising agent for mitigating inflammatory disorders.

Phyllanthi Fructus ameliorates hyperuricemia and kidney injure via inhibiting uric acid synthesis, modulating urate transporters, and alleviating inflammation

Phyllanthi Fructus, known as Yuganzi (YGZ), is a unique medicine and food homologous fruit with both medicinal and nutritional properties. Its historical use in treating hyperuricemia (HUA) and gout is well-documented. However, the precise therapeutic effects and potential molecular mechanisms remain unclear. In this study, an experimental rat modelling by a high-fat/high-sugar diet and potassium oxonate/adenine oral administration was used to evaluate the pharmacodynamic effects of YGZ. Network pharmacology, molecular docking and molecular dynamics simulation were utilized to elucidate the potential mechanisms. Supplementation with YGZ effectively ameliorated HUA by inhibiting xanthine oxidase activity, and enhancing uric acid excretion through up-regulating of OAT1 and ABCG2, while down-regulating of URAT1. Furthermore, YGZ supplementation enhanced superoxide dismutase activity, reduced malondialdehyde content, and inhibited the secretion of IL1B, IL6, TNFα, ICAM1, VCAM1, TGFβ1, and NF-κB protein expression. Network pharmacology analysis indicated that YGZ influences 138 targets, modulating the disease network via lipid and atherosclerosis, insulin resistance, HIF-1, TNF, IL-17, TLRS, and NF-κB signaling pathways. Molecular docking analysis suggested that organic acids (e.g. ellagic acid, gallic acid) and flavonoids (e.g. quercetin, delphinidin, luteolin, epigallocatechin gallate) exhibited superior binding abilities to key targets (e.g. XDH, ABCG2, URAT1, OAT1, IRS1, PTGS2, TLR4). Noteworthy, molecular dynamics simulations confirmed that epigallocatechin gallate binds to URAT1 with the greatest stability. These results provide substantial evidence for the therapeutic efficacy of YGZ and establish a theoretical foundation for the development of natural products in treating hyperuricemia.

NSDHL contributes to breast cancer stem-like cell maintenance and tumor-initiating capacity through TGF-β/Smad signaling pathway in MCF-7 tumor spheroid

BackgroundNAD(P)-dependent steroid dehydrogenase-like protein (NSDHL), which is involved in breast tumor growth and metastasis, has been implicated in the maintenance of cancer stem cells. However, its role in regulating breast cancer stem-like cells (BCSCs) remains unclear. We have previously reported the clinical significance of NSDHL in patients with estrogen receptor-positive (ER +) breast cancer. This study aimed to elucidate the molecular mechanisms by which NSDHL regulates the capacity of BCSCs in the ER + human breast cancer cell line, MCF-7.MethodsNSDHL knockdown suppressed tumor spheroid formation in MCF-7 human breast cancer cells grown on ultralow-attachment plates. RNA sequencing revealed that NSDHL knockdown induced widespread transcriptional changes in the MCF-7 spheroids. TGF-β signaling pathway was the most significantly enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway (fold change ≥ 2, P ≤ 0.05) identified in NSDHL-knockdown MCF-7 spheroids compared with the control. In orthotopic tumor models injected with NSDHL-knockdown MCF-7 spheroids, tumor initiation and growth were strongly suppressed compared with those in the control.ResultsBCSC populations with CD44+/CD24- and CD49f+/EpCAM + phenotypes and high ALDH activity were decreased in NSDHL-knockdown MCF-7 spheroids and xenograft tumors relative to controls, along with decreased secretion of TGF-β1 and 3, phosphorylation of Smad2/3, and expression of SOX2. In RNA-sequencing data from The (TCGA) database, a positive correlation between the expression of NSDHL and SOX2 was found in luminal-type breast cancer specimens (n = 998). Our findings revealed that NSDHL plays an important role in maintaining the BCSC population and tumor-initiating capacity of ER-positive MCF-7 spheroids, suggesting that NSDHL is an attractive therapeutic target for eliminating BCSCs, thus preventing breast cancer initiation and progression.ConclusionsOur findings suggest that NSDHL regulates the BCSC/tumor-initiating cell population in MCF-7 spheroids and xenograft tumors.

Huaxian formula prevents the progression of radiation-induced pulmonary fibrosis by inhibiting the pro-fibrotic effects of macrophages

Ethnopharmacological relevanceThe Huaxian formula (HXF), a traditional Chinese medicine (TCM) remedy, specifically targets the pathological factors of “heat toxicity” and “phlegm stasis” induced by radiation in radiation-induced pulmonary fibrosis (RIPF). It works by clearing heat and invigorating the blood, addressing these key factors in the development of RIPF. Aim of the studyThe HXF has demonstrated potential in preventing RIPF, although its underlying mechanisms remain unclear. This study aims to investigate the efficacy, molecular targets, and mechanisms of action of HXF. Materials and methodsThe major constituents of the HXF were identified by ultra performance liquid chromatography and tandem mass spectrometry (UPLC-MS). C57BL/6j mice were divided into four groups: control (Ctrl), HXF alone (HXF), 17Gy-irradiation alone (IR), and irradiation plus HXF (IR + HXF). Lung damage and fibrosis were assessed by histopathological staining, and the flow cytometry and immunohistochemistry (IHC) were used to detect the macrophages phenotype of lung tissues in vivo at 16 weeks post-irradiation. Transcriptomic sequencing and bioinformatics analyses identified key genes modulated by HXF. In vitro assays included flow cytometry, western bolt, and quantitative PCR (qPCR) explored the impact of HXF on macrophage polarization and fibrotic activity, while co-culture experiments of the macrophage conditional medium and mouse embryo fibroblast NIH/3T3 investigated macrophage-fibroblast interactions. Results20 major constituents of HXF were identified. And the in vivo results revealed significant lung damage and fibrosis in the IR group, which were notably mitigated in the IR + HXF group. And HXF has been shown to significantly inhibit the infiltration of M2-type macrophages in lung tissues. Transcriptomic analysis identified differentially expressed genes (DEGs) such as Arg1, Mmp10, and Fgf23. Bioinformatics enrichment analysis indicated that these DEGs are involved in pathways related to the inhibition of extracellular matrix formation and inflammation. In vitro, HXF-containing serum reduced M2-type macrophage polarization and decreased the secretion of Arginase1 and TGFβ1. Conditioned medium from HXF-treated macrophages suppressed fibroblast activation. ConclusionHXF's preventive effects on RIPF involve multiple targets and mechanisms, including the modulation of Arg1, Mmp10, and Fgf23 expression. By inhibiting the pro-fibrotic capacity of macrophages, HXF suppresses fibroblast activation and collagen production, thereby alleviating lung fibrosis. These findings underscore the potential of HXF as a preventive strategy in managing RIPF.

Epoxymicheliolide Reduces Radiation-Induced Senescence and Extracellular Matrix Formation by Disrupting NF-κB and TGF-β/SMAD Pathways in Lung Cancer.

Lung cancer is a major cause of cancer-related mortality, and radiotherapy is often limited by tumor resistance and side effects. This study explores whether epoxymicheliolide (ECL), a compound from feverfew, can enhance radiotherapy efficacy in lung cancer. We tested ECL on A549 and PC-9 lung cancer cell lines to evaluate its effect on x-ray irradiation. We measured apoptosis, NF-κB pathway inhibition, TGF-β secretion reduction, and epithelial-mesenchymal transition suppression. Invivo, C57BL/6 mice with lung tumors received ECL and radiotherapy. ECL enhanced the antiproliferative effects of x-ray irradiation, induced apoptosis in senescent cells, inhibited the NF-κB pathway, reduced TGF-β levels, and suppressed epithelial-mesenchymal transition. ECL also inhibited tumor growth and improved survival in mice. ECL is a promising adjunct to radiotherapy for lung cancer, improving treatment outcomes by targeting multiple tumor progression mechanisms. It offers potential for enhanced management of lung cancer.

MiR-1226-5p is involved in radioresistance of colorectal cancer by activating M2 macrophages through suppressing IRF1

BackgroundAlthough the representative treatment for colorectal cancer (CRC) is radiotherapy, cancer cells survive due to inherent radioresistance or resistance acquired after radiation treatment, accelerating tumor malignancy and causing local recurrence and metastasis. However, the detailed mechanisms of malignancy induced after radiotherapy are not well understood. To develop more effective and improved radiotherapy and diagnostic methods, it is necessary to clearly identify the mechanisms of radioresistance and discover related biomarkers.MethodsTo analyze the expression pattern of miRNAs in radioresistant CRC, sequence analysis was performed in radioresistant HCT116 cells using Gene Expression Omnibus, and then miR-1226-5p, which had the highest expression in resistant cells compared to parental cells, was selected. To confirm the effect of miR-1226-5 on tumorigenicity, Western blot, qRT-PCR, transwell migration, and invasion assays were performed to confirm the expression of EMT factors, cell mobility and invasiveness. Additionally, the tumorigenic ability of miR-1226-5p was confirmed in organoids derived from colorectal cancer patients. In CRC cells, IRF1, a target gene of miR-1226-5p, and circSLC43A1, which acts as a sponge for miR-1226-5p, were discovered and the mechanism was analyzed by confirming the tumorigenic phenotype. To analyze the effect of tumor-derived miR-1226-5p on macrophages, the expression of M2 marker in co-cultured cells and CRC patient tissues were confirmed by qRT-PCR and immunohistochemical (IHC) staining analyses.ResultsThis study found that overexpressed miR-1226-5p in radioresistant CRC dramatically promoted epithelial-mesenchymal transition (EMT), migration, invasion, and tumor growth by suppressing the expression of its target gene, IRF1. Additionally, we discovered circSLC43A1, a factor that acts as a sponge for miR-1226-5p and suppresses its expression, and verified that EMT, migration, invasion, and tumor growth are suppressed by circSLC43A1 in radioresistant CRC cells. Resistant CRC cells-derived miR-1226-5p was transferred to macrophages and contributed to tumorigenicity by inducing M2 polarization and secretion of TGF-β.ConclusionsThis study showed that the circSLC43A1/miR-1226-5p/IRF1 axis is involved in radioresistance and cancer aggressiveness in CRC. It was suggested that the discovered signaling factors could be used as potential biomarkers for diagnosis and treatment of radioresistant CRC.

CKIP-1 inhibits M2 macrophage polarization to suppress the progression of gastric cancer by inactivating JAK/STAT3 signaling.

Gastric cancer (GC) is a frequently occurring malignancy with poor prognosis. Casein kinase 2 interacting protein-1 (CKIP-1) is a PH domain-containing protein implicated in regulating tumorigenesis and macrophage homeostasis. This study aimed to elucidate the role and potential mechanism of CKIP-1 in the progression of GC. CKIP-1 expression in GC tumor and para-carcinoma tissues was detected using RT-qPCR. Then, human monocyte cell line THP-1 was treated with PMA, interleukin (IL)-4 and IL-13 to induce M2-polarized macrophages. CD206, arginase-1 (Arg-1) and transforming growth factorβ1 (TGFβ1) expression in M2-polarized macrophages with or without CKIP-1 overexpression was evaluated. Moreover, GC cell lines (MKN45 and HGC27 cells) were co-cultured with CKIP-1-overexpressed M2-polarized macrophages, and the viability, migration and invasion of GC cells were measured. Additionally, immunoblotting assessed the expression of JAK/STAT3 signaling-related proteins and STAT3 agonist Colivelin was used to treat GC cells to perform the rescue experiments to analyze the changes of malignant phenotypes of GC cells. Results showed that CKIP-1 was downregulated in GC tissues and M2-polarized macrophages. CKIP-1 overexpression inhibited M2 macrophage polarization and decreased TGFβ1 secretion. Besides, elevated CKIP-1 expression in M2-polarized macrophages inhibited the viability, migration and invasion of GC cells. Furthermore, CKIP-1 overexpression inactivated JAK2/STAT3 signaling in GC cells by inhibiting TGFβ1 level. Specifically, Colivelin treatment abrogated the influences of CKIP-1 upregulation on the malignant phenotypes of GC cells. Collectively, CKIP-1 inhibits M2 macrophage polarization to suppress the progression of GC by inactivating JAK/STAT3 signaling pathway.

On the pathogenesis of COVID-19: the role of transforming growth factor beta

Proteins of the transforming growth factor beta (TGF-β) family regulate numerous cellular processes that are essential in the pathogenesis of acute respiratory distress syndrome (ARDS), contributing to increased alveolar epithelial permeability, activation of fibroblasts, and extracellular matrix remodeling. TGF-β is involved in the pathogenesis of inflammatory respiratory diseases during the development of COVID-19. SARS-CoV-2 leads to complex immune responses that include the release of inflammatory cytokines, increased activity of mast cells, and the release of mast cell secretome, in particular profibrotic enzymes and cytokines, including TGF-β.Tryptaseand chymase-positive mast cells play a major role in pulmonary fibrosis and embolism in COVID-19. Mast cell chymase is angiotensin-converting enzyme 2-independent due to extracellular formation of angiotensin II in the interstitium; it also activates TGF-β and other molecules, thereby playing a role in tissue remodeling. Mast cell β-tryptase increases the secretion of TGF-β1 by airway smooth muscle tissue and the expression of α-smooth muscle actin (α-SMA). TGF-β also induces the generation of mitochondrial reactive oxygen species (ROS), which enhances the production of ROS in lung fibroblasts. TGF-β is crucial for induing the synthesis of extracellular matrix components by fibroblasts.The review is devoted to the structure of TGF-β, the sources of its secretion and functions, the mechanism of its involvement in the pathogenesis of COVID-19, and the possibility of its use as a prognostic marker of COVID-19 severity.

Autoinduction-Based Quantification of In Situ TGF-β Activity in Native and Engineered Cartilage.

Transforming growth factor beta (TGF-β) is a potent growth factor that regulates the homeostasis of native cartilage and is administered as an anabolic supplement for engineered cartilage growth. The quantification of TGF-β activity in live tissues in situ remains a significant challenge, as conventional activity assessments (e.g., Western blotting of intracellular signaling molecules or reporter cell assays) are unable to measure absolute levels of TGF-β activity in three-dimensional tissues. In this study, we develop a quantification platform established on TGF-β's autoinduction response, whereby active TGF-β (aTGF-β) signaling in cells induces their biosynthesis and secretion of new TGF-β in its latent form (LTGF-β). As such, cell-secreted LTGF-β can serve as a robust, non-destructive, label-free biomarker for quantifying in situ activity of TGF-β in live cartilage tissues. Here, we detect LTGF-β1 secretion levels for bovine native tissue explants and engineered tissue constructs treated with varying doses of media-supplemented aTGF-β3 using an isoform-specific ELISA. We demonstrate that: 1) LTGF-β secretion levels increase proportionally to aTGF-β exposure, reaching 7.4- and 6.6-fold increases in native and engineered cartilage, respectively; 2) synthesized LTGF-β exhibits low retention in both native and engineered cartilage tissue; and 3) secreted LTGF-β is stable in conditioned media for 2 weeks, thus enabling a reliable biological standard curve between LTGF-β secretion and exposed TGF-β activity. Accordingly, we perform quantifications of TGF-β activity in bovine native cartilage, demonstrating up to 0.59 ng/mL in response to physiological dynamic loading. We further quantify the in situ TGF-β activity in aTGF-β-conjugated scaffolds for engineered tissue, which exhibits 1.81 ng/mL of TGF-β activity as a result of a nominal 3 μg/mL loading dose. Overall, cell-secreted LTGF-β can serve as a robust biomarker to quantify in situ activity of TGF-β in live cartilage tissue and can be potentially applied for a wide range of applications, including multiple tissue types and tissue engineering platforms with different cell populations and scaffolds.

Evaluation and the mechanism of ShengXian and JinShuiLiuJun decoction in the treatment of silicotic fibrosis: An integrated network pharmacology, life omics, and experimental validation study

BackgroundSilicosis is a systemic disease characterized by extensive fibrosis due to prolonged exposure to silica dust, with rising incidence rates significantly impacting global public health. ShengXian and JinShuiLiuJun Decoction (SXD) is a Chinese medicinal preparation containing a variety of medicinal plants. It has shown notable clinical efficacy in treating silicotic fibrosis in China. However, the precise mechanisms underlying its therapeutic effects remain unclear. This study integrates network pharmacology, multi-omics analysis, and experimental validation to investigate the potential mechanisms by which SXD treats silicotic fibrosis. ObjectiveThe study aims to investigate the therapeutic efficacy of SXD in treating silicotic fibrosis and to elucidate its underlying molecular mechanisms. MethodsHPLC-Q-TOF-MS was used to identify the active components of SXD, and combined with network pharmacology, metabolomics, and transcriptomics, the mechanism of SXD in treating silicotic fibrosis was explored from multiple perspectives. The therapeutic effect of SXD was assessed through HE staining, Masson staining, Micro CT imaging, pulmonary function tests, and hydroxyproline content in lung tissue. Finally, network pharmacology and multi-omics findings were validated using molecular docking. CETSA, immunofluorescence, SPR, and Western blotting were used to analyze key factors in the NF-κB pathway at the animal, cellular, and molecular levels. ResultsSXD treatment improved lung function in silicosis rats, reduced inflammatory cell infiltration, collagen deposition, fibrosis and other pathological changes, and inhibited the protein expression of TNF-α, IL-17A, and IL-1β, and NF-κB in lung tissue. HPLC-Q-TOF-MS combined with network pharmacology identified key compounds such as Liquiritigenin, 3-Methoxynobiletin, Isomangiferin, Hesperidin, shogaol, and Ligustroflavone, which likely exert therapeutic effects through the TNF, IL-17, NF-κB, and TGF-β signaling pathways. Transcriptomics and metabolomics results revealed that SXD up-regulated the expression of NF-κB pathway-related genes (NFKBIA, NFKBIZ) and key regulators of the retinol metabolism pathway, while down-regulating pro-inflammatory genes (IL1B, IL17A, IL6). Experimental findings confirmed that SXD suppressed the expression of NF-κB pathway-related proteins and upstream activators TNF-α, IL-17A, and IL-1β, as well as their receptors, in both lung tissue and cellular models. Additionally, SXD-containing serum had a direct, non-toxic effect on MRC-5 cells, effectively inhibiting collagen expression and TGF-β secretion. SXD also had a positive effect on collagen production and extracellular matrix (ECM) aggregation in fibroblasts. Molecular dynamics studies showed that SXD directly binds to NF-κB and IκB. ConclusionSXD exerts therapeutic effects on silicotic fibrosis by inhibiting NF-κB signaling transduction mediated by TNF-α, IL-17A, and IL-1β, and suppressing fibroblast activation.

Alpha(α)-mangostin (Xanthone of Garcinia mangostana L.): Augmenting Macrophages Activity for an Effective Diabetic Wound Healing

Diabetic wounds are particularly difficult to treat medically because they heal at a slower pace than regular wounds. Macrophages are essential in all stages of normal wound healing, including inflammation, proliferation and rem odelling. When wound healing is affected, macrophages can reduce the level of growth factor and increase the level of interleukin-6 (IL-6), disrupt the balance between tissue inhibitors of metalloproteinase (TIMPs) and matrix metalloproteinase (MMPs), which can slow down healing. Alpha(α)-mangostin, a natural xanthone derived from the pericarp of the mangosteen, has gained considerable attention due to its anti-inflammatory properties, suggesting its potential to promote wound healing. However, its exact role in healing diabetic foot ulcers, common in diabetes, remains unclear. Hence, this study aims to explore how α-mangostin might affect diabetic wound healing by evaluating its impact on PDGF, CTGF, BFGF, VEGF, TGF-β, MMP-9, TIMP-2 and IL-6 secretion in macrophage cells. Human monocytic macrophages (THP-1) were incubated with a 35 mM glucose solution for 72 h to create a glucose-enriched medium. The cells were then incubated with α-mangostin (0.15, 2.5 and 5 µg/mL) together with 35 mM glucose. Carboxymethyl cellulose (CMC) served as positive controls; glucose-enriched media and media-alone served as negative controls. Protein expression was measured using ELISA. α-mangostin (2.5 µg/mL) increased the levels of PDGF and VEGF and decreased the level of MMP-9 compared to glucose controls. There was no significant difference in other growth factors, TIMP-2 and IL-6 protein levels across any of the treatment groups compared to glucose controls. In conclusion, α-mangostin particularly at 2.5 µg/mL demonstrated a significant increase in PDGF and VEGF levels while simultaneously reducing MMP-9 in macrophage cells under glucose-induced conditions. These findings suggest that α-mangostin holds the potential for enhancing the healing of chronic wounds in diabetic conditions. HIGHLIGHTS Treatment of macrophages (THP-1 cells) with 2.5 µg/mL Alpha (α)-mangostin in a high glucose medium led to a significant increase in PDGF and VEGF secretion compared to glucose control. Treatment of the cells with 2.5 µg/mL Alpha (α)-mangostin in a high glucose medium led to a significant reduction of MMP-9 secretion compared to glucose control. There is no significant effects of Alpha (α)-mangostin on IL-6 and TIMP secretion compared to controls This study suggests that Alpha (α)-mangostin may be beneficial in promoting diabetic wound healing via stimulation of PDGF and VEGF secretion and reducing MMP-9 levels. GRAPHICAL ABSTRACT

SNRK regulates TGFβ levels in atria to control cardiac fibrosis.

Atrial fibrosis is central to the pathology of heart failure (HF) and atrial fibrillation (AF). Identifying precise mechanisms underlying atrial fibrosis will provide effective strategies for clinical intervention. This study investigates a metabolic serine threonine kinase gene, sucrose non-fermenting related kinase (SNRK), that we previously reported to control cardiac metabolism and function. Conditional knockout of Snrk in mouse cardiomyocytes ( Snrk cmcKO) leads to atrial fibrosis and subsequently HF. The precise mechanism underlying cardiomyocyte SNRK-driven repression of fibrosis is not known. Here, using mouse, rat, and human tissues, we demonstrate that SNRK expression is high in atria, especially in atrial cardiomyocytes. SNRK expression correlates with lower levels of pro-fibrotic protein transforming growth factor-beta 1 (TGFβ1) in the atrial cardiomyocytes. In HL-1 adult immortalized mouse atrial cells, using siRNA approaches, we show that Snrk knockdown cells show more TGFβ1 secretion, which was also observed in heart lysates from Snrk cardiac-specific knockout mice in vivo. These effects were exacerbated upon infusion of Angiotensin II. Results from Snrk knockdown cardiomyocytes co-cultured with cardiac fibroblasts suggest that SNRK represses TGFβ1 signaling (Smad 2/3) in atrial CMs and prevents paracrine cardiac fibroblast activation (α-SMA marker). In conclusion, high SNRK expression in atria regulates cardiac homeostasis, by preventing the release of TGFβ1 secretion to block cardiac fibrosis. These studies will assist in developing heart chamber-specific fibrosis therapy for non-ischemic HF and AF.

Updates on the controversial roles of regulatory lymphoid cells in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is the most common and severe form of pulmonary fibrosis, characterized by scar formation in the lung interstitium. Transforming growth factor beta (TGF-β) is known as a key mediator in the fibrotic process, acting on fibroblasts and mediating their proliferation and differentiation into myofibroblasts. Although the immune system is not considered responsible for the initiation of IPF, markers of tolerogenic immunity define the pro-fibrotic microenvironment in the lungs. In homeostatic conditions, regulatory T cells (Tregs) constitute the main lymphoid population responsible for maintaining peripheral tolerance. Similar to Tregs, regulatory B cells (Bregs) represent a recently described subset of B lymphocytes with immunosuppressive functions. In the context of IPF, numerous studies have suggested a role for Tregs in enhancing fibrosis, mainly via the secretion of TGF-β. In humans, most studies show increased percentages of Tregs associated with the severity of IPF, although their exact role remains unclear. In mice, the most commonly used model involves triggering acute lung inflammation with bleomycin, leading to a subsequent fibrotic process. Consequently, data are still conflicting, as Tregs may play a protective role during the inflammatory phase and a deleterious role during the fibrotic phase. Bregs have been less studied in the context of IPF, but their role appears to be protective in experimental models of lung fibrosis. This review presents the latest updates on studies exploring the implication of regulatory lymphoid cells in IPF and compares the different approaches to better understand the origins of conflicting findings.

Resolvin D2/GPR18 signaling enhances monocytic myeloid-derived suppressor cell function to mitigate abdominal aortic aneurysm formation.

Abdominal aortic aneurysm (AAA) formation is a chronic vascular pathology characterized by inflammation, leukocyte infiltration, and vascular remodeling. The aim of this study was to delineate the protective role of Resolvin D2 (RvD2), a bioactive isoform of specialized pro-resolving lipid mediators, via G-protein-coupled receptor 18 (GPR18) receptor signaling in attenuating AAAs. Importantly, RvD2 and GPR18 levels were significantly decreased in aortic tissue of AAA patients compared with controls. Furthermore, using an established murine model of AAA in C57BL/6 (WT) mice, we observed that treatment with RvD2 significantly attenuated aortic diameter, pro-inflammatory cytokine production, immune cell infiltration (neutrophils and macrophages), elastic fiber disruption, and increased smooth muscle cell α-actin expression as well as increased TGF-β2 and IL-10 expressions compared to untreated mice. Moreover, the RvD2-mediated protection from vascular remodeling and AAA formation was blocked when mice were previously treated with siRNA for GPR18 signifying the importance of RvD2/GPR18 signaling in vascular inflammation. Mechanistically, RvD2-mediated protection significantly enhanced infiltration and activation of monocytic myeloid-derived suppressor cells (M-MDSCs) by increasing TGF-β2 and IL-10 secretions in a GPR18-dependent manner to attenuate aortic inflammation and vascular remodeling. Collectively, this study demonstrates that RvD2 treatment induces an expansion of myeloid-lineage committed progenitors, such as M-MDSCs, activates GPR18-dependent signaling to enhance TGF-β2 and IL-10 secretion, and mitigates SMC activation that contributes to resolution of aortic inflammation and remodeling during AAA formation.

A Strategy Involving Microporous Microneedles Integrated with CAR-TREM2-Macrophages for Scar Management by Regulating Fibrotic Microenvironment.

Dipeptidyl peptidase 4 (DPP4) positive fibroblasts play a pivotal role in scar development following skin injury. Heterogeneous vascular endothelial cells (ECs) within scarred areas retain the capacity to drive tissue regeneration and repair. Simultaneously, TREM2 macrophages play a crucial role in the progression and resolution of fibrosis by engaging in mutual regulation with ECs. However, effective strategies to inhibit scar formation through multi-factor regulation of the scar microenvironment remain a challenge. Here, CAR-TREM2-macrophages (CAR-TREM2-Ms) capable of targeting DPP4+ fibroblasts and modulating ECs subtype within the scar microenvironment are engineered to effectively prevent scarring. Hydrogel microporous microneedles (mMNs) are employed to deliver CAR-TREM2-Ms, which can effectively alleviate scar. Single-cell transcriptome sequencing (scRNA-seq) analysis reveals that CAR-TREM2-Ms can modify ECs fibrotic phenotype and regulate fibrosis by suppressing the profibrotic gene leucine-rich-alpha-2-glycoprotein 1 (Lrg1). In vitro experiments further demonstrate that CAR-TREM2-Ms improve the scar microenvironment by phagocytosing DPP4+ fibroblasts and suppressing TGFβ secretion. This, in turn, inhibits the phenotypic conversion of LRG1 ECs and provides multifactorial way of alleviating scars. This study uncovers the evidence that mMNs attached to CAR-TREM2-Ms may exert vital influences on skin scarring through the regulation of the skin scar microenvironment, providing a promising approach for treating posttraumatic scarring.

Cytomegalovirus results in poor graft function via bone marrow-derived endothelial progenitor cells.

Poor graft function (PGF), characterized by myelosuppression, represents a significant challenge following allogeneic hematopoietic stem cell transplantation (allo-HSCT) with human cytomegalovirus (HCMV) being established as a risk factor for PGF. However, the underlying mechanism remains unclear. Bone marrow endothelial progenitor cells (BM-EPCs) play an important role in supporting hematopoiesis and their dysfunction contributes to PGF development. We aim to explore the effects of CMV on BM-EPCs and its underlying mechanism. We investigated the compromised functionality of EPCs derived from individuals diagnosed with HCMV viremia accompanied by PGF, as well as after infected by HCMV AD 169 strain in vitro, characterized by decreased cell proliferation, tube formation, migration and hematopoietic support, and increased apoptosis and secretion of TGF-β1. We demonstrated that HCMV-induced TGF-β1 secretion by BM-EPCs played a dominant role in hematopoiesis suppression in vitro experiment. Moreover, HCMV down-regulates Vitamin D receptor (VDR) and subsequently activates p38 MAPK pathway to promote TGF-β1 secretion by BM-EPCs. HCMV could infect BM-EPCs and lead to their dysfunction. The secretion of TGF-β1 by BM-EPCs is enhanced by CMV through the activation of p38 MAPK via a VDR-dependent mechanism, ultimately leading to compromised support for hematopoietic progenitors by BM EPCs, which May significantly contribute to the pathogenesis of PGF following allo-HSCT and provide innovative therapeutic strategies targeting PGF.

Research on curcumin mediating immunotherapy of colorectal cancer by regulating cancer associated fibroblasts.

The objective was to investigate curcumin's (Cur) function and associated molecular mechanisms in regulating tumor immunity in colon cancer. Primary cancer-associated fibroblasts (CAFs) from mouse CT26 colon cancer tumors were isolated. Validation of primary CAFs using immunofluorescence assay was done. Cell Counting Kit-8 experiments, real-time quantitative PCR (qPCR), and enzyme linked immunosorbent assay experiments were conducted to investigate how curcumin affected the growth and cytokine secretion functions of CAFs. The effect of curcumin on regulating PD-L1 expression on CT26 cells through CAFs in vitro was explored through coculture of CAFs and tumor cells, qPCR, and western blot experiments. A mouse colon cancer cell model was established in Balb/c nude mice to explore the effect of curcumin on colon tumor cells. Changes in the tumor microenvironment were detected by flow cytometry to explore the synergistic effect of curcumin combined with anti-PD-1 monoclonal antibody in the treatment of mouse colon cancer. In vitro, curcumin prevented the growth and TGF-β secretion of CT26 cells. At the same time, curcumin inhibited the secretion of TGF-β by CAFs, thereby downregulating the PD-L1 expression of CT26 cells. In vivo, curcumin combined with anti-PD-1 antibodies can further enhance the inhibitory effect of PD-1 antibodies on tumors and increase the number of tumor-suppressing immune cells in the tumor microenvironment, such as M1 macrophages and CD8 T cells, thus inhibiting tumors. Immune M2 macrophages, regulatory T cells, and other cells were reduced. In conclusion, curcumin reduces the expression of PD-L1 in colon cancer cells and improves the tumor immune microenvironment by inhibiting the proliferation of CAFs and the secretion of TGF-β. Curcumin and anti-PD-1 treatment have synergistic inhibitory effects on colon cancer.