Matrix Metalloproteinase Research Articles

A Pvr-AP-1-Mmp1 signaling pathway is activated in astrocytes upon traumatic brain injury.

Traumatic brain injury (TBI) caused by external mechanical forces is a major health burden worldwide, but the underlying mechanism in glia remains largely unclear. We report herein that Drosophila adults exhibit a defective blood-brain barrier, elevated innate immune responses, and astrocyte swelling upon consecutive strikes with a high-impact trauma device. RNA sequencing (RNA-seq) analysis of these astrocytes revealed upregulated expression of genes encoding PDGF and VEGF receptor-related (Pvr, a receptor tyrosine kinase), adaptor protein complex 1 (AP-1, a transcription factor complex of the c-Jun N-terminal kinase pathway) composed of Jun-related antigen (Jra) and kayak (kay), and matrix metalloproteinase 1 (Mmp1) following TBI. Interestingly, Pvr is both required and sufficient for AP-1 and Mmp1 upregulation, while knockdown of AP-1 expression in the background of Pvr overexpression in astrocytes rescued Mmp1 upregulation upon TBI, indicating that Pvr acts as the upstream receptor for the downstream AP-1-Mmp1 transduction. Moreover, dynamin-associated endocytosis was found to be an important regulatory step in downregulating Pvr signaling. Our results identify a new Pvr-AP-1-Mmp1 signaling pathway in astrocytes in response to TBI, providing potential targets for developing new therapeutic strategies for TBI.

A Pvr–AP-1–Mmp1 signaling pathway is activated in astrocytes upon traumatic brain injury

Traumatic brain injury (TBI) caused by external mechanical forces is a major health burden worldwide, but the underlying mechanism in glia remains largely unclear. We report herein that Drosophila adults exhibit a defective blood–brain barrier, elevated innate immune responses, and astrocyte swelling upon consecutive strikes with a high-impact trauma device. RNA sequencing (RNA-seq) analysis of these astrocytes revealed upregulated expression of genes encoding PDGF and VEGF receptor-related (Pvr, a receptor tyrosine kinase), adaptor protein complex 1 (AP-1, a transcription factor complex of the c-Jun N-terminal kinase pathway) composed of Jun-related antigen (Jra) and kayak (kay), and matrix metalloproteinase 1 (Mmp1) following TBI. Interestingly, Pvr is both required and sufficient for AP-1 and Mmp1 upregulation, while knockdown of AP-1 expression in the background of Pvr overexpression in astrocytes rescued Mmp1 upregulation upon TBI, indicating that Pvr acts as the upstream receptor for the downstream AP-1–Mmp1 transduction. Moreover, dynamin-associated endocytosis was found to be an important regulatory step in downregulating Pvr signaling. Our results identify a new Pvr–AP-1–Mmp1 signaling pathway in astrocytes in response to TBI, providing potential targets for developing new therapeutic strategies for TBI.

Molybdenum interferes with MMPs/TIMPs expression to reduce the receptivity of porcine endometrial epithelial cells

To investigate the effect of trace element molybdenum (Mo) on the receptivity of porcine endometrial epithelial cells (PEECs) and evaluate Mo toxicity and its potential molecular mechanisms, Mo-treated PEECs models were established by incubating the cells with various concentrations of medium containing Mo (0, 0.005, 0.020, 0.200, and 5 mmol/L MoNa2O4·2H2O). The results showed that Mo disrupted the morphology and ultrastructure of PEECs, triggered blurred cell edges, cell swelling, cell cycle arrest, and increased apoptosis. At the molecular level, Mo treatment activated the TGF-β1/SMAD2 and PI3K/AKT1 pathways, causing a significant increase in matrix metalloproteinase (MMP)-9 and MMP-2 protein expression. Accompanied by markedly increased tissue inhibitors matrix metalloproteinase (TIMP)-2 and decreased TIMP-1, the balance of MMP2/TIMP-2 and MMP-9/TIMP-1 were disrupted. Ultimately, the receptivity of PEECs was destroyed by excessive Mo, which is revealed by the significant decrease of receptive marker molecules, including leukemia inhibitory factor (LIF), integrins β3 (ITGβ3), heparin-binding epidermal growth factor (HB-EGF), and vascular endothelial growth factor (VEGF). To sum up, the current study demonstrated the potential toxicity of Mo to PEECs, indicating reproductive toxicity at high Mo concentrations and suggesting that the content of Mo should be evaluated as a potential risk factor.

Potential Strategies for Overcoming Drug Resistance Pathways Using Propolis and Its Polyphenolic/Flavonoid Compounds in Combination with Chemotherapy and Radiotherapy

Conventional cancer treatments include surgical resection, chemotherapy, hyperthermia, immunotherapy, hormone therapy, and locally targeted therapies such as radiation therapy. Standard cancer therapies often require the use of multiple agents, which can activate nuclear factor kappa B (NF-κB) in tumor cells, leading to reduced cell death and increased drug resistance. Moreover, the use of multiple agents also contributes to added toxicity, resulting in poor treatment outcomes. Cancer cells gradually develop resistance to almost all chemotherapeutics through various mechanisms, such as drug efflux, alterations in drug metabolism and transport, changes in signal transduction pathways, enhanced DNA repair capacity, evasion of apoptosis, increased mutations, reactivation of drug targets, interaction with the cancer microenvironment, cancer cell-stroma interactions, epithelial–mesenchymal transition (EMT)-mediated chemoresistance, epigenetic modifications, metabolic alterations, and the effect of cancer stem cells (CSCs). Developing new strategies to improve chemotherapy sensitivity while minimizing side effects is essential for achieving better therapeutic outcomes and enhancing patients’ quality of life. One promising approach involves combining conventional cancer treatments with propolis and its flavonoids. These natural compounds may enhance tumor response to treatment while reducing toxicity. Propolis and its components can sensitize cancer cells to chemotherapeutic agents, likely by inhibiting NF-κB activation, reprogramming tumor-associated macrophages (TAMs; an M2-like phenotype), and thereby reducing the release of matrix metalloproteinase (MMP)-9, cytokines, chemokines, and the vascular endothelial growth factor (VEGF). By reducing TAMs, propolis and its components may also overcome EMT-mediated chemoresistance, disrupt the crosstalk between macrophages and CSCs, inhibit the maintenance of stemness, and reverse acquired immunosuppression, thus promoting an antitumor response mediated by cytotoxic T-cells. This review highlights the potential of flavonoids to modulate the responsiveness of cancer to conventional treatment modalities. The evidence suggests that novel therapeutic strategies incorporating flavonoids could be developed to improve treatment outcomes. The positive effects of combining propolis with chemotherapeutics include reduced cytotoxicity to peripheral blood leukocytes, liver, and kidney cells. Therefore, polyphenolic/flavonoid components may hold potential for use in combination with chemotherapeutic agents in the clinical treatment of various types of cancers.

The Effect of the Root Bark of Lycium chinense (Lycii Radicis Cortex) on Experimental Periodontitis and Alveolar Bone Loss in Sprague-Dawley Rats

Lycii Radicis Cortex (LRC), the dried root bark of Lycium chinese Mill., has traditionally been used as a medicinal herb in East Asia to treat fever and hyperhidrosis. In the present study, we investigated the effects of LRC extract on ligation-induced experimental periodontitis and associated alveolar bone loss in rats. Twenty-four hours after ligation placement, LRC was orally administered once daily for 10 days. Firstly, LRC administration inhibited anaerobic bacterial proliferation and inflammatory cell infiltration in gingival tissues. Additionally, LRC exhibited anti-inflammatory effects by reducing the expression of inflammatory mediators, including prostaglandin E2, interleukin-1β, and tumor necrosis factor-α. LRC treatment also downregulated mRNA expression of these inflammatory mediators in lipopolysaccharide-stimulated RAW 264.7 cells by inhibiting the mitogen-activated protein kinases and nuclear factor-κB (NF-κB) signaling pathways. Furthermore, LRC showed an antioxidant effect by decreasing the malondialdehyde level and inducible nitric oxide synthase activity in gingival tissues. Moreover, LRC effectively prevented the connective tissue degradation by inhibiting matrix metalloproteinase-8 expression and the loss of collagen-occupied areas in gingival tissues. LRC also decreased the receptor activator of NF-κB ligand/osteoprotegerin (RANKL/OPG) ratio, as well as the number and occupied areas of osteoclasts on the alveolar bone surface, thereby inhibiting alveolar bone loss. In summary, these findings suggest that LRC is a promising medicinal herb for alleviating periodontitis and related alveolar bone loss through its antimicrobial, anti-inflammatory, and antioxidant properties.

Harnessing the Power of Non-diabetic Benefits of Metformin Derived from <i>Galega officinalis</i>: Focus on Wound Healing

This review explores the potential of metformin, a widely used type 2 diabetes medication, in accelerating wound healing. Derived from guanidine compounds found in <i>Galega officinalis</i>, a plant with a long history in traditional medicine, metformin has been recognized for its minimal side effects. Beyond its primary role in diabetes treatment, metformin shows promising non-diabetic benefits, particularly in wound healing. Research indicates that metformin enhances wound healing through multiple mechanisms. It increases circulating endothelial progenitor cells, improves vascular function, and regulates thrombospondin-1 levels. Metformin also modulates the AMPK/mTOR/NLRP3 inflammasome signaling pathway, promoting M2 macrophage polarization, which is crucial for tissue repair. Additionally, it reduces pro-inflammatory cytokines, increases growth factors, and decreases matrix metalloproteinases. Studies have shown that topical application of metformin accelerates wound contraction, closure, and overall healing. Furthermore, it has been found to reduce fibrosis-related gene expression and improve collagen synthesis. With chronic wounds affecting millions globally and causing significant healthcare costs, there is a pressing need for improved wound healing agents. This review advocates for further research to establish clinical guidelines on using metformin to enhance wound healing. By harnessing metformin’s pleiotropic effects, healthcare providers may offer personalized treatments that not only manage diabetes but also promote wound healing.

The role of fecal matrix metalloprotease-9 as a non-invasive marker in diagnosis and assessment of clinical activity in inflammatory bowel disease patients

BackgroundInflammatory bowel disease is characterized by chronic and relapsing inflammation of the gastrointestinal tract, including two prominent forms: Crohn’s disease and ulcerative colitis. Determining diagnostic biomarkers for predicting disease activity and treatment response remains a challenging aspect.Aim of the workThe purpose of our research was to compare fecal CP and fecal MMP-9, two non-invasive biomarkers for inflammatory bowel disease (IBD), and to find out how fecal MMP-9 levels relate to disease activity by looking at how they relate to clinical, endoscopic, and histologic scores of disease activity.Patients and methodsThis study was performed on 80 subjects divided into 3 groups: group A: 30 patients with Crohn’s disease evidenced by endoscopy ileocolonoscopy, upper GI endoscopy, and tissue biopsy (15 patients with active disease and 15 patients in remission). Group B: 30 patients with ulcerative colitis disease evidenced by colonoscopy and tissue biopsy (15 patients with active disease and 15 patients in remission). Group C: 20 age-matched and sex-matched healthy controls. All participants underwent a thorough history review, comprehensive physical examination, complete laboratory tests, and C-reactive protein measurements. A quantitative enzyme-linked immunosorbent assay was used to determine the levels of fecal matrix metalloproteinase MMP 9 for both the patients and the controls. Ulcerative colitis was evaluated using the Mayo score, Montreal classification, and the Riley histological score. Additionally, Crohn’s disease was assessed with the Crohn’s Disease Activity Index, the Simple Endoscopic Score for Crohn’s Disease, and the D’Haens histological score.ResultsComparing fecal MMP-9 with fecal calprotectin (FC), we found that fecal MMP-9 was superior to FC in differentiating active Crohn’s disease from inactive Crohn’s disease, although there was no significant difference between FC and MMP-9 (P-value = 0.561). However, in ulcerative colitis, FC was superior to MMP-9 in distinguishing active UC from inactive UC, but again, there was no significant difference between FC and MMP-9 (P-value = 0.0731).In both the ulcerative colitis and Crohn’s disease groups, fecal MMP-9 could discriminate between patients in remission and those with active disease. Fecal matrix metalloproteinase-9 (MMP-9) was discovered to be a significant marker for assessing the clinical activity of both Crohn’s disease (CD) and ulcerative colitis (UC), with an AUC of 0.998 for CD and 0.991 for UC. Fecal MMP-9 demonstrated great sensitivity (93.33%), specificity (100%), positive predictive value (PPV) of 100%, and negative predictive value (NPV) of 93.7% (with a P-value < 0.001) using cutoff values of > 0.34 ng/mL for CD and > 0.36 ng/mL for UC. There was a strong positive correlation between fecal MMP-9 and endoscopic and clinical scores of disease activity.ConclusionFecal MMP-9 has emerged as a promising biomarker for evaluating the clinical activity of both Crohn’s disease and ulcerative colitis. It demonstrated superior diagnostic performance compared to fecal calprotectin in distinguishing active from inactive disease, especially in Crohn’s disease. Although fecal calprotectin outperformed MMP-9 in identifying active ulcerative colitis, the differences between the two markers were not statistically significant, suggesting that they may complement each other in clinical practice. Furthermore, fecal MMP-9 is capable of assessing the activity of endoscopically visible inflammatory bowel disease (IBD), which could help reduce the need for invasive endoscopic procedures.

Correlation of MMP-9 (Matrix Metalloproteinase 9) and SMA (Smooth Muscle Actin) expression with Basal Cell Carcinoma’s risk of recurrence

Basal Cell Carcinoma (BCC) is the most common cancer in many countries, with its incidence steadily rising. Data from the Indonesian Pathologists Association show that among 1,530 skin cancer cases, BCC was the most frequent (39.93%), followed by Squamous Cell Carcinoma (23%) and Malignant Melanoma (7.9%). According to the 2018 WHO classification, BCC is divided into Low-Risk and High-Risk groups based on the risk of recurrence. BCC invades surrounding tissues through extracellular matrix degradation and enhanced cell motility, driven by the expression of MMP-9 (Matrix Metalloproteinase 9) and SMA (Smooth Muscle Actin). This study aims to evaluate the expression of MMP-9 and SMA in BCC using immunohistochemistry and analyze their correlation with the risk of recurrence. A total of 40 paraffin blocks from BCC patients diagnosed between 2019 and 2021 at Dr. Saiful Anwar General Hospital in Malang, Indonesia, were sampled. The blocks were sectioned, stained with MMP-9 and SMA antibodies, and examined for positive expression indicated by brown staining in the cytoplasm of tumor cell and peritumoral stroma. Spearman correlation showed r = 0.811 for MMP-9 and r = 0.857 for SMA (p &lt; 0.05, CI: 95%), indicating a significant relationship between these markers and the risk of recurrence. Higher MMP-9 and SMA expression corresponded to a higher risk of BCC recurrence, suggesting their potential as prognostic biomarkers. However, further research is needed to assess recurrence risk more accurately and determine the most appropriate therapy.

Mild hypercapnia before reperfusion reduces ischemia-reperfusion injury in hyperacute ischemic stroke rat model.

Endovascular thrombectomy has a recanalization rate over 80%; however, approximately 50% of ischemic stroke patients still experience dependency or mortality. Recently, clinical trials demonstrated the benefits of administering neuroprotective agents prior to endovascular thrombectomy. Additionally, recent studies showed neuroprotective effects of mild hypercapnia in patients resuscitated after cardiac arrest. However, its efficacy in ischemic stroke remains unclear. We aimed to investigate whether carbon dioxide (CO2) per-conditioning has neuroprotective effects in rat models with middle cerebral artery occlusion (MCAO). Rat models received intermittent inhalation of mixed gas during the MCAO period. After surgery, behavioral assessments, infarct size measurement, immunohistochemistry, and western blot analysis were performed. We found CO2 per-conditioning reduced infarct size and neurological deficit. The number of 8-hydroxy-2-deoxyguanosine (8-OHdG) positive cells and matrix metalloproteinase 9 (MMP-9)/platelet derived growth factor receptor beta (PDGFRβ) double positive cells were significantly decreased after CO2 per-conditioning. The expressions of tight junction protein and pericytes survival were preserved. This study underscores mild hypercapnia before reperfusion not only reduces neurologic deficit and infarct size, but also maintains the integrity of the blood-brain barrier and neurovascular unit, alongside mitigating oxidative stress in hyperacute stroke rat models. Therapeutic mild hypercapnia before reperfusion is promising and requires further clinical application.

Enocyanin promotes osteogenesis and bone regeneration by inhibiting MMP9.

Enocyanin (ENO), an anthocyanin extracted from grapes, has been shown to exert inhibitory effects on acid phosphatase and inflammation; however, its role in osteogenesis and bone formation is currently unknown. The present study aimed to investigate the effects of ENO on osteogenesis in vitro and bone formation in vivo, and to explore the rudimentary mechanisms. KusaO cells were employed to evaluate the osteogenic role of ENO in vitro by Alizarin red S staining, ALP staining, quantitative PCR and western blotting, and an in vivo analysis of the therapeutic effects of ENO on a femoral fracture model was performed using stereo microscope, micro‑CT and histological staining. To further investigate the underlying mechanisms, mRNA sequencing was employed to investigate the changes in gene expression and the downstream pathways after ENO treatment. The results showed that ENO could promote the osteogenic differentiation of KusaO cells in vitro and bone fracture regeneration in vivo. Mechanistically, ENO was highly related to bone formation, including the 'Wnt signalling pathway', 'bone development' and 'bone mineralization'. In addition, matrix metalloproteinase 9 (MMP9) was identified as one of the targets of ENO in its promotional role in osteogenesis. In conclusion, ENO may represent a therapeutic candidate for bone regeneration in bone fractures by regulating osteogenesis and bone formation via MMP9.

Biomarkers of rheumatoid arthritis-associated interstitial lung disease: a systematic review and meta-analysis

BackgroundInterstitial Lung Disease (ILD) represents the most common extra-articular manifestation of Rheumatoid Arthritis (RA) and is a major cause of mortality. This study aims to identify and evaluate biomarkers associated with Rheumatoid Arthritis-Associated Interstitial Lung Disease (RA-ILD).MethodsWe searched PubMed, Cochrane Library, EMBASE, and Web of Science databases for studies related to biomarkers of RA-ILD up until October 7, 2023. The Newcastle-Ottawa Scale (NOS) and standards recommended by the Agency for Healthcare Research and Quality (AHRQ) were used for quality assessment, and meta-analysis was conducted using Stata18.0 software.ResultsA total of 98 articles were assessed for quality, 48 of which were included in the meta-analysis. 83 studies were of high quality, and 15 were of moderate quality. The meta-analysis showed significant differences in biomarkers such as C-Reactive Protein (CRP), Erythrocyte Sedimentation Rate (ESR), Anti-Cyclic Citrullinated Peptide (anti-CCP) antibody, Rheumatoid Factor (RF), Krebs von den Lungen-6 (KL-6), Surfactant Protein D (SP-D), Carcinoembryonic Antigen (CEA), Carbohydrate Antigen 19-9 (CA19-9), Matrix Metalloproteinase-7 (MMP-7), C-X-C Motif Chemokine Ligand 10 (CXCL-10), and Neutrophil-to-Lymphocyte Ratio (NLR) between RA-ILD patients and RA patients. However, Platelet-to-Lymphocyte Ratio [Platelet-to-Lymphocyte Ratio (PLR)], Cancer Antigen 125 [Cancer Antigen 125 (CA-125)], and Cancer Antigen 153 [Cancer Antigen 153 (CA-153)] did not show significant differences between the two groups. KL-6, MMP-7, and Human Epididymis Protein 4 (HE4) are negatively correlated with lung function, and KL-6 is associated with the prognosis of RA-ILD.ConclusionsBiomarkers hold promising clinical value for prediction, diagnosis, severity assessment, and prognosis evaluation in RA-ILD. However, these findings need to be validated through multicenter, large-sample, prospective cohort studies.Systematic review registrationhttps://www.crd.york.ac.uk/prospero/, identifier CRD42023448372.

The influence of interleukin-4 on transendothelial transport of low-density lipoproteins

BACKGROUND: Cytokines are important participants in the atherosclerotic process. The product of T-helpers and mast cells, interleukin-4, causes activation of endothelial cells and induces polarization of macrophages into anti-inflammatory M2 phenotype. AIM: The aim was to study the influence of interleukin-4 on the activation of transendothelial transport of low-density lipoproteins. MATERIALS AND METHODS: Low-density lipoproteins transendothelial transport was evaluated in a two-chamber model on a monolayer of human endothelial cell line EA.hy926. For that, 200 mkg/ml of low-density lipoproteins, and 1, or 10, or 100 ng/ml of interleukin-4, or 10, or 50 ng/ml of interleukin-6, or 50 ng/ml of tumor necrosis factor, or 10 ng/ml of interleukin-4 and 50 ng/ml of tumor necrosis factor, or a phosphate buffer saline were added to the cells on 24 h. The integrity of endothelial monolayer was controlled by the passage through 1 mkg/ml of fluorescein Na. The levels of mRNA and proteins in the cells were determined by reverse transcription polymerase chain reaction and Western blotting, the activity of matrix metalloproteinases-1, -2 and -9 in the culture medium — by zymography, interleukin-6 and -8 concentrations — by enzyme-linked immunosorbent assay. RESULTS: Interleukin-4 had no effect on the passage of low-density lipoproteins through the monolayer of endothelial cells in basal and tumor necrosis factor stimulation conditions. At the same time, interleukin-4 suppressed interleukin-8 secretion by cells and increased their production of interleukin-6. The latter also did not cause the changes in the permeability of endothelial monolayer. In addition, interleukin-4 did not affect the expression of CAV, SCARB1, ACVRL1 genes, encoding proteins involved in low-density lipoproteins transendothelial transport. An addition of interleukin-4 or -6 to the cells did not change the activity of the matrix metalloproteinases. CONCLUSIONS: Interleukin-4 does not affect the transendothelial transport of low-density lipoproteins, while modulating the production of other cytokines by endothelial cells. In the future, it is necessary to establish the effect of a wider range of cytokines produced by intimal cells on low-density lipoproteins transendothelial transport, as well as to clarify the molecular mechanisms of influence of tumor necrosis factor on this process in order to identify new targets for atherosclerosis therapy.

MicroRNA-145-5p restricts cardiac scar resolution during cardiac regeneration

Abstract Background Human hearts have a very limited capacity to renew cardiomyocytes following injury. The lost myocardium is permanently replaced with noncontractile fibrotic tissue, consequently leading to heart failure. In contrast, zebrafish retain cardiac regenerative capacity during their lifetime. After injury, zebrafish hearts undergo transient fibrotic scarring that subsequently resolves and is replaced with new cardiomyocytes over time. Thus, understanding the molecular mechanisms governing cardiac scar resolution in zebrafish could offer insights into enhancing the regenerative capacities of human hearts. Objective We aimed to decipher the molecular pathways associated with zebrafish cardiac scar resolution. Methods We investigated the mRNA and miRNA responses to injury at 14 days post-injury by high-throughput transcriptome profiling of RNAs isolated from healthy or cryoinjured hearts. The prediction of miRNA-mRNA interactions was performed to identify the most differentially expressed miRNAs and their target genes. These miRNAs and genes were validated in zebrafish regenerating hearts and in the left ventricles of ischemic cardiomyopathy or dilated cardiomyopathy patients. The potential role of identified miRNAs in cardiac scar resolution was investigated in human cardiac fibroblasts. Results Principal component analyses identify two distinct clusters in both the mRNAome and miRNAome corresponding to healthy and injured hearts, indicating significant changes in transcriptome profiles during zebrafish cardiac regeneration. Gene set enrichment analyses indicate that molecular pathways involved in extracellular matrix organization and inflammatory response are markedly activated whereas genes associated with mitochondrial organization and oxidative phosphorylation are downregulated in injured hearts. We observed the downregulation of miR-145-5p and the upregulation of procollagen V in the injured hearts. In contrast to zebrafish, in the left ventricles of ischemic cardiomyopathy patients, miR-145-5p is significantly upregulated and procollagen V α1 is downregulated. Theoretical prediction of miRNA-mRNA interactions indicates procollagen V α1 is negatively correlated with miR-145-5p. Overexpression of miR-145-5p in human cardiac fibroblasts downregulates collagen V α1 and alpha smooth muscle actin, upregulates procollagen I and matrix metalloproteinase 9, and inhibits cell proliferation and migration. In contrast, inhibition of miR-145-5p upregulates collagen V α1 and alpha smooth muscle actin, downregulates procollagen I and matrix metalloproteinase 9, and stimulates cell proliferation and migration. Conclusion Our study suggests that miR-145-5p may play a role in the suppression of myofibroblast transdifferentiation via collagen V α1, which restricts scar resolution and cardiac repair.

Assessment of circulating biomarkers and hemodynamic response during stress to detect early cardiopulmonary complications in systemic sclerosis

Abstract Background Systemic sclerosis (SSc) is characterised by persistent immune-inflammatory system activation and excessive extracellular matrix (ECM) accumulation leading to fibrosis. Exercise Doppler Echocardiography (EDE) is a promising method to detect the early changes of fibrosis-related pulmonary and myocardial complications, like elevated left ventricular filling pressure or stress-induced pulmonary hypertension (PH). Aims The study aims to assess the linkage between the activity of fibrosis markers and abnormal exercise haemodynamics during stress in patients with SSc. Methods A total of 18 patients with SSc were enrolled in the single-centre prospective study (age 54±15,5years, 94,4 % women). SSc patients with resting PH and moderate to severe pulmonary fibrosis were excluded. According to a standardised protocol, all subjects underwent resting and exercise echocardiography on a semi-recumbent cycle ergometer with an incremental (25 watts) workload up to the maximally tolerated workload. Measurements focused on the left ventricular diastolic function (E/e’) and right ventricular haemodynamics (estimated systolic pulmonary pressure: PASP, right ventricular coupling: TAPSE/PASP, pulmonary vascular resistance: PVR). Blood samples were taken immediately before the stress test, and the Matrix Metalloproteinase-9 and 2 (MMP-9, MMP-2) levels were assessed with gelatin zymography method. Results During the EDE, PASP from baseline increased significantly (24,6mmHg±11 vs 38±16mmHg, p &amp;lt;0,0001), also PVR (1,2±0,49 vs 1,5±0,15 Wood unit, p&amp;lt;0,001) RV coupling was decreased significantly (1,2±0,68 vs 0,93±0,5, p&amp;lt;0,001). Left ventricular E/e’ was also increased during the stress (8,2±2 vs 10,5±5,1, p&amp;lt;0,05). Enzymatically active MMP-9 level was significantly correlated with RV coupling at rest and stress (p&amp;lt;0,05, r 0,63 at rest and r 0,52 at stress) and negatively correlated with PASP (p&amp;lt;0,05, r:-0,62 at rest and r -0,5 at stress). MMP-2 level only negatively correlated with resting PASP (p&amp;lt;0,05, r:-0,527). The left ventricular parameters did not show any relationship with MMP levels. Conclusions The level of circulating MMP-9 predicts haemodynamic behaviour during stress in SSc. MMPs could be a promising marker for detecting early changes in the right ventricle-pulmonary circulation unit.

Macrophages overexpressing interleukin-10 target and prevent atherosclerosis: regression of plaque formation and reduction in necrotic core

Abstract Background Atherosclerosis, a slowly progressing inflammatory disease, is characterized by the presence of monocyte-derived macrophages. Interventions targeting the inflammatory characteristics of atherosclerosis hold promising potential. Although interleukin (IL)-10 is widely acknowledged for its anti-inflammatory effects, systemic administration of IL-10 has limitations due to its short half-life and significant systemic side effects. Purpose We aimed to investigate the effectiveness of an approach designed to overexpress IL-10 in macrophages and subsequently introduce these genetically modified cells into ApoE-/- mice to promote atherosclerosis regression. Methods We engineered RAW264.7 cells to overexpress IL-10 (referred to as IL-10M) using lentivirusvectors. The ApoE-/- mice were divided into two groups based on the timing of the intervention. The early intervention group (n = 45) received intravenous tail injections from the beginning of Western diet (WD) at six weeks old. The late intervention group (n = 45) started receiving injections at 16 weeks old, 2 months after being fed the WD. Both the early and late intervention group stopped receiving injections after 5 months of being fed the WD. Results The IL-10M exhibited robust IL-10 secretion, maintained phagocytic function, improved mitochondrial membrane potentials, reduced superoxide production and showed a tendency toward the M2 phenotype when exposed to inflammatory stimuli. IL-10M can selectively target plaques in ApoE-/- mice, and oil red staining of the entire aorta unequivocally demonstrated that intervention with IL-10M elicited a substantial reduction in plaque area. H&amp;E staining revealed that mice treated with IL-10M in the early intervention group showed a significant reduction in the ratio of plaque area to lumen area. However, the late intervention group did not exhibit statistically significant differences. Notably, mice treated with IL-10M exhibited significantly smaller necrotic cores and reduction in matrix metalloproteinase 9 within the aortic plaques in both the early and late intervention groups. Additionally, the administration of IL-10M showed no obvious side effects. Conclusion We developed an anti-inflammatory protein delivery system based on engineered macrophages that can target atherosclerotic plaques and reduce the plaque area and necrotic core. This approach has a promising safety profile and has the potential to be a therapeutic strategy for the intervention of atherosclerosis.

Insulin-like growth factor binding protein 2 predicts course of concomitant right-ventricular dilation and tricuspid regurgitation after transcatheter edge-to-edge mitral valve repair

Abstract Aims Right ventricular (RV) dilation and secondary tricuspid regurgitation (TR) are highly prevalent comorbidities in patients with mitral regurgitation and are associated with a worse prognosis. TR improvement after successful transcatheter edge-to-edge mitral valve repair (M-TEER) is reported regularly, however specific factors contributing to the recovery of RV function and TR after M-TEER are poorly understood. Particularly the role of serum biomarkers in this context is unclear. We aimed to identify specific biomarkers associated with the course of concomitant RV dilation and TR after M-TEER. Methods and Results We prospectively included 242 patients undergoing M-TEER at our center and obtained pre-procedural blood samples for biomarker analysis. A commercial multiplex protein assay (Cardiovascular III, Olink, Uppsala, Sweden) was used to quantify expression levels of 92 defined biomarkers. We then analyzed differences in biomarker expression between patients with and without right ventricular reverse remodeling (RVRR) as defined by improvement of concomitant TR by at least one grade and/or downsizing of the basal RV diameter of at least 10%. 242 patients were included in this analysis, 94 had no/mild concomitant TR at baseline, 148 had moderate/severe TR. RV diameters correlated with TR severity and were significantly larger in patients with moderate/severe TR. At baseline, expression of numerous cardiometabolic biomarkers was significantly higher in patients with moderate/severe TR. These included NT-proBNP (1.9-fold, p &amp;lt; 0.001), matrix metalloproteinase 2 (1.4-fold, p &amp;lt; 0.001) as well as insulin-like growth factor binding proteins 1 (1.7-fold, p &amp;lt; 0.001), -2 (1.3-fold, p = 0.001) and -7 (1.4-fold, p &amp;lt; 0.001). Follow-up analysis was performed in patients with initial moderate/severe TR. The course of TR and RV dimensions three months after M-TEER could be assessed in 99 patients (56 with moderate TR, 43 with severe TR). RVRR had occurred in 50 patients (50.5%). Patients without RVRR had a higher prevalence of chronic pulmonary disease (24.5 vs. 2.2%, p &amp;lt; 0.001). No further differences in clinical characteristics were found. Specifically, RV diameter, systolic pulmonary artery pressure (sPAP) and right-ventricular systolic function did not differ substantially between both groups. Strikingly however, the expression of insulin-like growth factor binding protein 2 (IGFBP-2) was significantly higher in patients, who did not develop RVRR (fold change 1.3 compared to patients with RVRR, p = 0.022). After adjustment for covariates IGFBP-2 was independently associated with absence of RVRR (Odds Ratio 2.078, 95% Confidence interval 1.108 – 3.897, p = 0.023). Conclusions In patients undergoing M-TEER with concomitant moderate or severe TR, numerous cardiometabolic biomarkers including IGFBP-2 are upregulated. Higher levels of IGFBP-2 at baseline are independently associated with persistent TR and/or RV dilation after M-TEER.

C-C motif chemokine ligand 3 is associated with atherosclerotic plaque vulnerability and increased risk of mortality

Abstract Background and Purpose Chemokines play a crucial role in the inflammatory process underlying atherosclerotic plaque formation, progression and subsequent cardiovascular events. However, the specific role of C-C motif chemokine ligand 3 (CCL3) in atherosclerosis remains largely unexplored. This study aims to explore associations between intra-plaque levels of CCL3 and plaque vulnerability as well as to investigate the prognostic role of circulating CCL3 levels in patients undergoing carotid endarterectomy. Methods The CCL3 protein expression was measured using a proximity extension assay in 207 human carotid plaques and 558 plasma samples from patients undergoing carotid endarterectomy, all enrolled in the Carotid Plaque Imaging Project (CPIP) cohort. Protein expression is quantified as normalized protein expression (NPX), an arbitrary unit on a log2-scale. Plaque components and extracellular matrix including smooth muscle cells, macrophages, neutral lipids, intraplaque hemorrhage, collagen (by histology), and matrix metalloproteinases (assessed biochemically), were quantified. Plaque vulnerability index was calculated as the sum percentage of plaque areas stained for lipids, macrophages and hemorrhage, divided by the sum percentage of smooth muscle cells and collagen. Patients were followed up to 10.2 years to record cardiovascular events and mortality. Results Plaque and circulating levels of CCL3 were higher in symptomatic patients compared to asymptomatic patients (plaque, median NPX (interquartile range, IQR): 18.2 (17.4–19.1) vs 17.2 (16.4–18.0), P&amp;lt;0.001; plasma, median NPX (IQR): 1.78 (1.42–2.21) vs 1.56 (1.28–1.97), P&amp;lt;0.001). Plaque levels of CCL3 showed positive correlations with neutral lipids, macrophages, intraplaque hemorrhage, plaque vulnerability index and matrix metalloproteinases including MMP1, MMP2, MMP9, MMP10 and TIMP1, but inversely with smooth muscle cells. Among 511 patients with complete follow-up and circulating CCL3 measures, 144 (28.2%) patients developed cardiovascular events and 123 (24.1%) patients died. Elevated circulating CCL3 levels were associated with increased risk of cardiovascular events (hazard ratio (HR) per standard deviation (SD) = 1.40, 95% CI 1.06–1.84) and mortality (HR per SD=1.77, 95% CI 1.34–2.33), respectively. Higher levels of circulating CCL3 remained independently associated with an increased risk of mortality (HR per SD=1.50, 95% CI 1.09–2.04) even after adjustment for potential confounders. Conclusions Plaque levels of CCL3 are associated with plaque vulnerability features. Circulating levels of CCL3 predict higher risk of cardiovascular events and mortality among carotid endarterectomy patients.

Serpina3c deficiency aggravates vascular dysfunction and VSMC dysregulation through regulating adamts4 pathway activity in obese mice

Abstract Background Obesity leads to arterial stiffness (AS), which is an independent risk factor for cardiovascular disease. Vascular smooth muscle cell (VSMC) dysfunction is a critical step in the development of AS. Adamts4 (a disintegrin and metalloproteinase with thrombospondin motifs 4) promoting the ECM remodeling can regulate VSMC differentiation. Serpina3c is a serine protease inhibitor that plays a key role in VSMC proliferation and metabolic diseases. Purpose The present study aimed to investigate the function of Serpina3c in high-fat diet (HFD)-induced AS and regulation of VSMC phenotypic switching and possible mechanisms. Methods 8-week-old male Serpina3c-/- and C57BL/6 mice were fed normal diet (ND) or HFD for 12 weeks. The adipocyte-specific Serpina3c overexpression (AAV8-Serpina3c) were constructed and injected in situ into visceral or perivascular adipose tissue (AT) of Serpina3c-/- mice fed a 12-week HFD to test in vivo effect of AT-derived Serpina3c on arterial stiffness. In vivo vascular stiffness was analyzed by obtaining pulse wave velocity (PWV) measurements. Aortic rings were dissected to assess the ex-vivo effects of Serpina3c deprivation on vascular contractile and diastolic function. Elastin van Gieson (EVG) and Hematoxylin-eosin (H&amp;E) staining were implemented to observe the pathological morphology of aortas. IP-Western analysis was performed for identifying Serpina3c-adamts4 interactions. Results The obese WT mice exhibited significantly increased PWV values, compared with ND-fed mice, which were further increased in HFD+Serpina3c-/- mice (Fig. 1A). Phenylephrine-induced vascular constriction was impaired in HFD fed mice and further deteriorated with Serpina3c deficiency (Fig. 1B). No differences were noted in the endothelial-dependent acetylcholine-mediated relaxation in HFD-fed mice. Notably, Serpina3c-/- mice exhibited poorer endothelium-independent sodium nitroprusside induced relaxation (Fig. 1C and D). The HFD+Serpina3c-/- mice showed an increased breakage of elastin fibres and medial thickness compared with the aortas of HFD+WT mice (Fig. 1E and F). Serpina3c deprivation aggravated collagen deposition and matrix metalloproteinases (MMPs, MMP2 and MMP9) accumulation. VSMC contractile gene α smooth muscle actin were upregulated and synthetic phenotype marker osteopontin were downregulated in HFD+WT mice. The effect was more pronounced in aortas with Serpina3c deficiency (Fig. 1G and H). Overexpression of serpina3c in both visceral and perivascular AT or adamts4 deprivation reversed the above phenotypes. Computer simulations and IP-Western results indicate that Serpina3c and adamts4 bind to and maintain the latter low-expression in response to obesity (Fig. 2). Conclusion Serpina3c interacts with adamts4 to maintain contractile phenotype of VSMC and suppress AS development in the context of nutrient excess. Serpina3c is a novel target for the prevention and treatment of obesity associated artery disease.Serpina3c maintains vascular functionSerpina3c interacts with adamts4

Lipoprotein(a) induces spontaneous aortic dissection via increasing monocyte mediated vascular smooth muscle cell phenotype transformation in human Lp(a) transgenic mice

Abstract Background Elevated lipoprotein(a) [Lp(a)] is a prevalent, independent risk factor of atherosclerotic cardiovascular disease and aortic valve stenosis. Recent studies have reported that high levels of Lp(a) are strongly associated with aortic dissection (AD), independent of other cardiovascular risk factors. However, orthologues of Lp(a) are only found in humans, Old World monkeys, apes, and hedgehogs. The lack of a proper animal model has hindered elucidation of the true pathophysiological mechanisms of Lp(a). Here, we conducted the first humanized Lp(a) transgenic mice experiment to verify the pathological mechanism of Lp(a) in aortic dissection. Methods We conducted ApoE knock out and human ApoA transgenic mice via CRISPR-Cas9 and then crossed with human ApoB transgenic mice to achieve high levels of human-like Lp(a) particles in plasma. Plasma was assayed by ELISA for the concentrations of each lipoprotein. Echocardiography was performed to detect aortic morphology in vivo. Single cell transcriptome analysis was performed on the dissection lesion. Cell interaction was examined in macrophage from Lp(a) transgenic mice and vascular smooth muscle cell (VSMC) coculture system. Result Our results indicate that the concentration of ApoA and ApoB in plasma were increased in transgenic mice fed a chow diet. Low density lipoprotein (LDL) levels were increased and shows that LDL is the major cholesterol carrier in these mice. We were surprised to find that the dissection of the ascending aortic arch could be seen by echocardiography in transgenic mice as early as 2 months, and transgenic mice showed significant increase in aortic enlargement, dissection, and rupture in both the thoracic and abdominal aortic regions, resulting in a survival rate of only 58% after 12 months. Single cell transcriptome analysis revealed that Lp(a) transgene induced the inflammatory response, dedifferentiation and pathological VSMC phenotypical switch, and matrix metalloproteinase expression in macrophages. Monocytes isolated from transgenic mice with elevated Lp(a) remain in a long-lasting primed state, as evidenced by an increased capacity to transmigrate and produce proinflammatory cytokines on stimulation. Monocytes isolated from wild type mice cultured in media with high level Lp(a) for 24h also showed the ability to facilitated cocultured VSMC phenotype transformation, which was reversed by E06, a monoclonal antibody blocking the oxidized phospholipids in Lp(a). Conclusion These findings demonstrate that Lp(a) induces spontaneous aortic dissection via increasing monocyte trafficking to the arterial wall, mediating proinflammatory responses and VSMC phenotype transformation through its OxPL content. The study presents a rodent model of spontaneous aortic dissection and provide a novel mechanism by which Lp(a) mediates aortic dissection.Graphical abstract

Fenebrutinib, a Bruton’s tyrosine kinase inhibitor, blocks distinct human microglial signaling pathways

BackgroundBruton’s tyrosine kinase (BTK) is an intracellular signaling enzyme that regulates B-lymphocyte and myeloid cell functions. Due to its involvement in both innate and adaptive immune compartments, BTK inhibitors have emerged as a therapeutic option in autoimmune disorders such as multiple sclerosis (MS). Brain-penetrant, small-molecule BTK inhibitors may also address compartmentalized neuroinflammation, which is proposed to underlie MS disease progression. BTK is expressed by microglia, which are the resident innate immune cells of the brain; however, the precise roles of microglial BTK and impact of BTK inhibitors on microglial functions are still being elucidated. Research on the effects of BTK inhibitors has been limited to rodent disease models. This is the first study reporting effects in human microglia.MethodsHere we characterize the pharmacological and functional properties of fenebrutinib, a potent, highly selective, noncovalent, reversible, brain-penetrant BTK inhibitor, in human microglia and complex human brain cell systems, including brain organoids.ResultsWe find that fenebrutinib blocks the deleterious effects of microglial Fc gamma receptor (FcγR) activation, including cytokine and chemokine release, microglial clustering and neurite damage in diverse human brain cell systems. Gene expression analyses identified pathways linked to inflammation, matrix metalloproteinase production and cholesterol metabolism that were modulated by fenebrutinib treatment. In contrast, fenebrutinib had no significant impact on human microglial pathways linked to Toll-like receptor 4 (TLR4) and NACHT, LRR and PYD domains-containing protein 3 (NLRP3) signaling or myelin phagocytosis.ConclusionsOur study enhances the understanding of BTK functions in human microglial signaling that are relevant to MS pathogenesis and suggests that fenebrutinib could attenuate detrimental microglial activity associated with FcγR activation in people with MS.