Matrix Metalloproteinase Research Articles

Milk fat globule-epidermal growth factor 8 exerts anti-osteoarthritis effects by inhibiting apoptosis and inducing autophagy in mouse chondrocytes

Osteoarthritis (OA) is a chronic degenerative joint disease, characterized by cartilage injury. Milk fat globule-epidermal growth factor 8 (MFG-E8) exhibited anti-inflammatory effects, with undefined mechanism in OA. Eighteen C57BL/6 J mice were randomized into Sham and destabilization of medial meniscus (DMM) groups, with DMM surgery for OA model establishment. Subsequently, DMM mice received rmMFG-E8 (50 ng/g) as rmMFG-E8 group (n = 6). HE staining and Safranin O/Fast green staining for cartilage tissue pathological damage, TUNEL staining for apoptosis, ELISA for pro-inflammatory factors, and immunohistochemistry were performed. Following extraction of primary mouse chondrocytes, cells were randomized into Control, OA (10 ng/mL IL-1β), OA + rmMFG-E8 (500 ng/mL), and OA + rmMFG-E8+3-MA (autophagy inhibitor, 5 mM) groups. Cell viability by CCK8, pro-inflammatory factors by qRT-PCR, and apoptosis by flow cytometry were detected. In vivo and in vitro, transmission electron microscopy for autophagy and Western blot for autophagy- and apoptosis-related expression were conducted. In vivo, DMM group showed severe cartilage tissue damage, higher matrix metalloproteinase 13 (MMP13), Cleaved caspase-3, Cleaved PARP, Bax, TNF-α, IL-1β, IL-6 levels, and lower Bcl-2, MFG-E8, Collagen II, LC3II/LC3I, Beclin1, and ATG5 expression. Further rmMFG-E8 intervention improved mobility and pathological damage in DMM mice, with lower MMP13 expression. In vitro, rmMFG-E8 in OA group reduced TNF-α, IL-1β, IL-6, Cleaved caspase-3, Cleaved PARP, Bax, and P62 levels, and enhanced cell viability, Bcl-2, LC3II/LC3I, Beclin1, and ATG5 expression. Further 3-MA treatment up-regulated apoptosis and decreased cell viability and autophagy. Therefore, MFG-E8 exerts anti-OA effects by inhibiting apoptosis and inducing autophagy, offering a new potential target for OA treatment.

Single-cell RNA sequencing reveals S100A8/A9hi neutrophils-induced endothelial cell death and lymphocyte infiltration after ischemic stroke

Stroke is a major global cause of death and disability, with ischemic stroke being the most common type. The disruption of the blood-brain barrier (BBB) is a key factor in the pathophysiology of ischemic stroke, allowing immune cells to infiltrate and worsening neuroinflammation. This study uses single-cell RNA sequencing (scRNA-seq) to examine the transcriptional changes in neutrophils, endothelial cells, and T cells during ischemic stroke. Our findings indicate a significant increase in neutrophil and lymphocyte infiltration, along with a notable decrease in endothelial cell populations, demonstrating severe BBB disruption. Differential gene expression analysis shows that endothelial cells lose important characteristics post-stroke, while lymphocytes activate cytotoxic pathways that may lead to neuronal damage. Additionally, we reveal the contrasting roles of CXCR2 and CXCR4 in neutrophil movement and identify neutrophil-derived damage-associated molecular patterns (DAMPs) and matrix metalloproteinases (MMPs) as key drivers of endothelial cell apoptosis. Notably, the S100A8/A9 inhibitor paquinimod significantly protects neurons and reduces lymphocyte infiltration, suggesting that targeting S100A8/A9 could be a promising therapeutic strategy for reducing neurological deficits after ischemic stroke. Overall, these results enhance our understanding of the complex interactions between immune cells and the BBB in ischemic stroke, paving the way for innovative therapeutic approaches aimed at maintaining brain integrity and improving patient outcomes.

Extracellular Matrix as a Target in Melanoma Therapy: From Hypothesis to Clinical Trials.

Melanoma is a malignant, highly metastatic neoplasm showing increasing morbidity and mortality. Tumor invasion and angiogenesis are based on remodeling of the extracellular matrix (ECM). Selective inhibition of functional components of cell-ECM interaction, such as hyaluronic acid (HA), matrix metalloproteinases (MMPs), and integrins, may inhibit tumor progression and enhance the efficacy of combination treatment with immune checkpoint inhibitors (ICIs), chemotherapy, or immunotherapy. In this review, we combine the results of different approaches targeting extracellular matrix elements in melanoma in preclinical and clinical studies. The identified limitations of many approaches, including side effects, low selectivity, and toxicity, indicate the need for further studies to optimize therapy. Nevertheless, significant progress in expanding our understanding of tumor biology and the development of targeted therapies holds great promise for the early approaches developed several decades ago to inhibit metastasis through ECM targeting.

Effects of Minocycline on Early Wound Healing after Implant Placement: An InVitro and Randomized Clinical Study.

To determine the invitro effects of minocycline on human gingival fibroblasts (HGFs), its clinical impact on early wound healing after implant placement, and its potential mechanism of action. First, we evaluated the invitro proliferation, migration, and collagen production of HGFs treated with different concentrations of minocycline, as well as the underlying mechanism. Subsequently, we conducted a clinical trial and randomly assigned 40 partially edentulous patients to either the test (minocycline hydrochloride treatment) or control (blank control) group immediately after implant surgery. The early wound healing score (EHS), pain index, gingival index (GI), modified sulcus bleeding index (mSBI), and peri-implant crevicular fluid samples were assessed or collected 3 and/or 7 days after surgery. In vitro, 1 μg/mL minocycline promoted the proliferation, migration, and collagen production of HGFs. Minocycline inhibited collagen degradation by downregulating the expression of matrix metalloproteinase-2 (MMP-2) and MMP-14 and upregulating tissue inhibitors of metalloproteinases-2. However, higher concentrations of minocycline, 10 and 100 μg/mL, exhibited adverse effects. In the randomised clinical trial, the test group showed significantly better clinical outcomes compared to the control group, with higher EHS and lower GI, mSBI, concentrations of IL-1β, IL-10, and TNF-α, and relative abundance of Streptococcus and gram-negative anaerobic bacteria. Small doses of minocycline (1 μg/mL) promoted the proliferation and migration of HGFs and inhibited collagen degradation invitro. Locally delivered minocycline after implant surgery improves clinical outcomes by promoting early wound healing, relieving the inflammatory response, and decreasing early colonisation of gram-negative anaerobic bacteria. This clinical trial was registered in the Chinese Clinical Trial Registry (registration number: ChiCTR2100044680).

The dual effect of fiber density and matrix stiffness on A549 tumor multicellular migration

The tumor microenvironment features dynamic biomechanical interactions between extracellular matrix physics and tumor progression. Tumor growth compresses the supportive matrix, and the stiffness-gradient guides tumor invasion. From the mechanical perspective, the complexity of the matrix topology involving durotaxis-driven metastasis remains lacking in a comprehensive description. In this study, A549 adenocarcinoma spheroids were exposed to a stiffness-and fiber-adjusted collagen matrix to examine the influence of collective motility. Centrifugated compression on the collagen constructs was adopted to mimic the matrix deformation in response to solid tumor development. Centrifugated compression physically stiffened and condensed collagen constructs simultaneously. Cultured with A549 spheroids for 7 days, compressed collagen constructs disadvantaged spheroid expansion without the effect of tumor proliferation potency but promoted matrix metalloproteinase activity corresponding to softened rigidity. Results suggested that the fibrous structure may counterbalance the matrix stiffness-induced motility.

The Role of Platelets in Atherosclerosis: A Historical Review.

Atherosclerosis is a chronic, multifactorial inflammatory disorder of large and medium-size arteries, which is the leading cause of cardiovascular mortality and morbidity worldwide. Although platelets in cardiovascular disease have mainly been studied for their crucial role in the thrombotic event triggered by atherosclerotic plaque rupture, over the last two decades it has become clear that platelets participate also in the development of atherosclerosis, owing to their ability to interact with the damaged arterial wall and with leukocytes. Platelets participate in all phases of atherogenesis, from the initial functional damage to endothelial cells to plaque unstabilization. Platelets deposit at atherosclerosis predilection sites before the appearance of manifest lesions to the endothelium and contribute to induce endothelial dysfunction, thus supporting leukocyte adhesion to the vessel wall. In particular, platelets release matrix metalloproteinases, which interact with protease-activated receptor 1 on endothelial cells triggering adhesion molecule expression. Moreover, P-selectin and glycoprotein Ibα expressed on the surface of vessel wall-adhering platelets bind PSGL-1 and β2 integrins on leukocytes, favoring their arrest and transendothelial migration. Platelet-leukocyte interactions promote the formation of radical oxygen species which are strongly involved in the lipid peroxidation associated with atherosclerosis. Platelets themselves actively migrate through the endothelium toward the plaque core where they release chemokines that modify the microenvironment by modulating the function of other inflammatory cells, such as macrophages. While current antiplatelet agents seem unable to prevent the contribution of platelets to atherogenesis, the inhibition of platelet secretion, of the release of MMPs, and of some specific pathways of platelet adhesion to the vessel wall may represent promising future strategies for the prevention of atheroprogression.

Hsa-miR-885-5p As Post Transcription Regulator of Matrix metalloproteinase 9 in Tuberculous Meningitis

hsa-miR-885-5p As Post Transcription Regulator of Matrix metalloproteinase 9 in Tuberculous Meningitis

Impacts of mesenchymal stem cells and hyaluronic acid on inflammatory indicators and antioxidant defense in experimental ankle osteoarthritis.

No effective treatment guarantees full recovery from osteoarthritis (OA), and few therapies have disadvantages. To determine if bone marrow mesenchymal stem cells (BMMSCs) and hyaluronic acid (HA) treat ankle OA in Wistar rats. BMMSCs were characterized using flow cytometry with detection of surface markers [cluster of differentiation 90 (CD90), CD105, CD34, and CD45]. Fifty male Wistar rats were divided into five groups of 10 rats each: Group I, saline into the right tibiotarsal joint for 2 days; Group II, monosodium iodate (MIA) into the same joint; Groups III, MIA + BMMSCs; Group IV, MIA + HA; and Group V, MIA + BMMSCs + HA. BMMSCs (1 × 106 cells/rat), HA (75 µg/rat), and BMMSCs (1 × 106 cells/rat) alongside HA (75 µg/rat) were injected intra-articularly into the tibiotarsal joint of the right hind leg at the end of weeks 2, 3, and 4 after the MIA injection. The elevated right hind leg circumference values in the paw and arthritis clinical score of osteoarthritic rats were significantly ameliorated at weeks 4, 5, and 6. Lipid peroxide significantly increased in the serum of osteoarthritic rats, whereas reduced serum glutathione and glutathione transferase levels were decreased. BMMSCs and HA significantly improved OA. The significantly elevated ankle matrix metalloproteinase 13 (MMP-13) mRNA and transforming growth factor beta 1 (TGF-β1) protein expression, and tumor necrosis factor alpha (TNF-α) and interleukin-17 (IL-17) serum levels in osteoarthritic rats were significantly downregulated by BMMSCs and HA. The effects of BMMSCs and HA on serum TNF-α and IL-17 were more potent than their combination. The lowered serum IL-4 levels in osteoarthritic rats were significantly upregulated by BMMSCs and HA. Additionally, BMMSCs and HA caused a steady decrease in joint injury and cartilage degradation. BMMSCs and/or HA have anti-arthritic effects mediated by antioxidant and anti-inflammatory effects on MIA-induced OA. MMP-13 and TGF-β1 expression improves BMMSCs and/or HA effects on OA in Wistar rats.

Long non-coding RNA HOTAIR promotes tumorigenesis by affecting proliferation, invasion, migration and apoptosis of liver cancer cells.

Increasing evidence shows that Hox transcript antisense RNA (HOTAIR) plays a vital role in liver cancer initiation and progression by affecting the proliferation, invasion, migration and apoptosis of liver cancer cells. However, the underlying mechanism of how HOTAIR exerts its functions in liver cancer cells remains unclear. Previous studies have shown that HOTAIR affects the invasion and migration of liver cancer cells by regulating the expression of E-cadherin. Snail2, a transcription factor involved in epithelial-mesenchymal transition, directly binds to the E-boxes of theE-cadherinpromoter to repress its transcription. The aim of the study was to examine the correlation between HOTAIR and Snail2 in the HOTAIR/Snail2/E-cadherin signal pathway and explore the role of HOTAIR in the proliferation, invasion, migration and apoptosis of liver cancer cells. 50 matched normal liver tissues and 373 liver cancer tissues were analysed and evaluated. HepG2 and SNU-387 cells were cultured and transfected with plasmids knocking down HOTAIR to disrupt HOTAIR expression. Cell scratch and transwell assays were performed to examine the migration and invasion of HepG2 and SNU-387 cells; in addition, the expression of MMP2 and MMP9 was detected by immunoblotting analysis, RT-qPCR analysis, immunofluorescence analysis, and bioinformatics analysis, which elucidated the regulatory relationship between HOTAIR and Snail2. We used flow cytometry and JC-1 probe analysis assays to clarify the function of HOTAIR in liver cancer cell apoptosis. The HOTAIR mRNA was upregulated in liver cancer tissues, which was related to worse overall survival. HOTAIR induced the expression of matrix metalloproteinase-9 (MMP9) and metalloproteinase-2 (MMP2), leading to degradation of extracellular matrix. HOTAIR knockdown significantly reduced the doubling time and inhibited cell migration and invasion of liver cancer cells. Furthermore, HOTAIR depletion induced mitochondrial-related apoptosis in HepG2 and SNU-387 cell lines. In this study, we proposed a novel mechanism in which HOTAIR promotes invasion and migration of liver cancer cells by regulating the nuclear localization of Snail2.

C1GALT1 high expression enhances the progression of glioblastoma through the EGFR-AKT/ERK cascade

Core1 β1,3-galactosyltransferase (C1GALT1) is an essential glycotransferase controlling the elongation of GalNAc-type O-glycosylation and its altered expression contributes tumor progression in various cancers. However, the mechanism how C1GALT1 influences gliomas remains unclear. Here，our results from The Cancer Genome Atlas (TCGA) database, The Chinese Glioma Genome Atlas (CGGA) database and the Clinical Proteomic Tumor Analysis Consortium (CPTAC) database showed that the expression of C1GALT1 was increased in higher grade gliomas namely glioblastoma compared with low grade gliomas or non-tumor tissues and significantly associated with poor survival. Downregulation of C1GALT1 suppressed cell proliferation, invasion, and migration in glioma cell lines. Consistent with the result in vitro, C1GALT1 knockdown distinctly inhibited the weight and tumor growth in nude mice. Mechanistically, C1GALT1 knockdown decreased the level of terminal galactose O-glycosylation and phosphorylation on epidermal growth factor receptor (EGFR). Moreover, The AKT/ERK phosphorylation was attenuated in C1GALT1 knockdown cells. And C1GALT1 knockdown decreased the expression of cyclinD1, matrix metalloproteinase 9 (MMP9) through the AKT/ERK signaling pathway Furthermore, transcription factor SP1 which the expression was found to be associated the C1GALT1 expression could bind to the promoter of C1GALT1 gene and regulated its expression. In conclusion, our data show that C1GALT1 enhances the progression of glioma by regulated the O-glycosylation and phosphorylation of EGFR and the subsequent downstream AKT/ERK signaling pathway. Therefore, C1GALT1 represents a potential target for the diagnosis and treatment of glioma.

Syringin ameliorates dextran sulphate colitis via alteration oxidative stress, inflammation NF-κB signalling pathway and gut microbiota.

The objective of the current study was to investigate the potential effects of syringin against dextran sulphate colitis (DSS)-induced ulcerative colitis (UC) in mice. In vitro study was performed on the RAW 264.7 cells and cytokines and inflammatory level were estimated. The oxidative stress, inflammatory cytokines, apoptosis and inflammatory parameters were estimated. The mRNA expression and faecal samples were estimated in the colon tissue. Syringin treatment enhanced the body weight, colon length and reduced the disease activity index (DAI), spleen index. Syringin treatment remarkably suppressed the level of nitric oxide (NO), myeloperoxidase (MPO), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) along with alteration of antioxidant parameters. Syringin treatment also altered level of cytokines in the serum and colon tissue; inflammatory parameters viz., platelet-activating factor (PAF), cyclooxygenase-2 (COX-2), prostaglandin (PGE2), inducible nitric oxide synthetase (iNOS), nuclear factor κ-B (NF-κB); matrix metalloproteinases (MMP) level. Syringin significantly (p < 0.001) enhanced the level of nuclear factor erythroid 2-related factor (Nrf2) and heme oxygenase-1 (HO-1). Syringin remarkably altered the relative abundance of gut microbiota like Firmicutes, Bacteroidetes, F/B ratio, Verrucomicrobia and Actinobacteria. Syringin exhibited the protective effect against DSS-induced UC in mice via alteration of NF-κB signalling pathway.

Radioiodinated Nanobody immunoPET probe for in vivo detection of CD147 in pan-cancer.

To develop the extracellular matrix metalloproteinase inducer (CD147)-targeting therapeutic strategies, accurate detection of CD147 expression in tumors is crucial. Owing to their relatively low molecular weights and high affinities, nanobodies (Nbs) may be powerful candidates for cancer diagnosis and therapy. In this study, we developed a novel CD147-targeted nanobody radiotracer, [124I]I-NB147, which provides guidance for the noninvasive detection of CD147-overexpressing cancers. CD147 expression in human cancers was detected via immunohistochemistry (IHC) on tissue microarrays (TMAs). Western blot (WB) and flow cytometry were used to screen CD147-positive malignant melanoma (MM), triple-negative breast cancer (TNBC), and pancreatic cancer (PCA) cell lines. The CD147 nanobody (NB147) was labeled with [124I]INa using Iodogen as the oxidizing agent and was purified by the PD-10 column. The physicochemical properties, affinity, metabolic characteristics, biodistribution, and immunoPET imaging of [124I]I-NB147 were evaluated Moreover, [18F]F-FDG was used as a control. Finally, CD147 expression analysis was performed via multiplex immunofluorescence (MxIF) and autoradiography on human cancer specimens and tumor-bearing mice tissues. TMAs results revealed that CD147 is highly expressed in MM, TNBC, and PCA. A CD147-specific nanobody, NB147, was successfully generated with excellent in vitro binding characteristics. [124I]I-NB147 was obtained with high radiochemical yield and purity, and was stable for at least 4h in vitro. WB and FCM revealed that CD147 was positive in A375, MDA-MB-435 and ASPC1 cells, whereas SK-MEL-28, 4T1 and BXPC3 cells presented low expression levels. The radio-ELISA results indicated that [124I]I-NB147 had a high binding affinity to CD147. The uptake of [124I]I-NB147 was significantly different between CD147 high-expression cells and CD147 low-expression cells (P < 0.001). The biological half-life of the distribution and clearance phases were 0.05h and 1.58h, respectively. In CD147-positive tumor models, the [124I]I-NB147 accumulated in A375, MDA-MB-435, and ASPC1 tumors, and the uptake value was significantly higher than that of [18F]F-FDG. Uptake in SK-MEL-28, BXPC3, and 4T1 tumors was not clearly observed. Finally, through autoradiography and histological studies, the correlation analysis between tumor uptake and CD147 expression level was determined. The high expression of CD147 in MM, TNBC, and PCA tissuesand in tumor cells was verified. The CD147 nanobody, NB147 was produced and radiolabeled to obtain the immunoPET probe, [124I]I-NB147, which showed high affinity to CD147 and precise visualization for accurate diagnosis of CD147-expressing lesions in different cancers. These results provide insight into the imaging and binding properties of nanobody NB147 over extended periods of time, reinforcing its potential in developing radionuclide therapies for CD147-positive cancer patients.

Effects of invigorating-spleen and anticancer prescription on extracellular signal-regulated kinase/mitogen-activated protein kinase signaling pathway in colon cancer mice model.

Colon cancer (CC) is one of the most common malignant tumors in the gastrointestinal system. Overall, CC had the third highest incidence but the second highest mortality rate globally in 2020. Nowadays, CC is mainly treated with capecitabine chemotherapy regimen, supplemented by radiotherapy, immunotherapy and targeted therapy, but there are still limitations, so Chinese medicine plays an important role. To investigate the effects of invigorating-spleen and anticancer prescription (ISAP) on body weight, tumor inhibition rate and expression levels of proteins in extracellular-signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) signaling pathway in CC mice model. The CC mice model were established and the mice were randomly divided into 5 groups, including the control group, capecitabine group, the low-dose, medium-dose and high-dose groups of ISAP, with 8 mice in each group, respectively. After 2 weeks of intervention, the body weight and tumor inhibition rate of mice were observed, and the expression of RAS, ERK, phosphorylated ERK (p-ERK), C-MYC and matrix metalloproteinase 2 (MMP2) proteins in the tissues of tumors were detected. Compared with the control group, the differences of body weight before and after treatment was much smaller in the groups of ISAP, with the smallest difference in the high-dose group of ISAP, while the capecitabine group had the greatest difference, indicating ISAP had a significant inhibiting effect on the growth of transplanted tumor in mice. The expression of RAS protein was decreased in the low- and medium-dose groups of ISAP, and the change of p-ERK was significant in the medium- and high- dose groups of ISAP. MMP2 protein expression was significantly decreased in both the low-dose and medium-dose groups of ISAP. There were no significant changes in ERK in the ISAP group compared to the capecitabine group, while RAS, MMP2, and C-MYC protein expression were reduced in the ISAP group. The expression level of C-MYC protein decreased after treated with ISAP, and the decrease was the most significant in the medium-dose group of ISAP. ISAP has a potential inhibiting effect on transplanted tumor in mice, and could maintain the general conditions, physical strength and body weight of mice. The expression levels of RAS, p-ERK, MMP2 and c-myc were also decreased to a certain extent. By inhibiting the expression of upstream proteins, the expression levels of downstream proteins in ERK/MAPK signaling pathway were significantly decreased. Therefore, it can be concluded that ISAP may exert an anti-tumor effect by blocking the ERK/MAPK signaling pathway and inhibiting the expression of MMP2 and c-myc proteins.

Role of MMPs in connective tissue breakdown and periodontal disease: A Review

Matrix metalloproteinases (MMPs) are a group of zinc-dependent enzymes that play a critical role in the degradation of extracellular matrix components, including collagen, elastin, and proteoglycans, making them central to tissue remodeling processes. In the context of periodontal disease, MMPs are key mediators of connective tissue breakdown and alveolar bone destruction, driven by chronic inflammation. This review focuses on the role of MMPs in periodontal disease, highlighting their regulation, activation mechanisms, and the interplay with inflammatory cytokines such as interleukins and tumor necrosis factor-alpha (TNF-α). Furthermore, the review discusses the contribution of specific MMPs, including MMP-1, MMP-8, and MMP-9, in periodontal tissue degradation and explores potential therapeutic approaches to inhibit MMP activity to prevent periodontal disease progression. By understanding the molecular basis of MMP involvement in periodontal pathology, this review aims to provide insights into novel therapeutic strategies aimed at mitigating connective tissue breakdown in periodontal disease.

Diabetes-induced alteration of metal ion levels declines the activity of MMPs to decrease aortic aneurysm risk

AimsDiabetes mellitus (DM) links the risk of cardiovascular diseases. Inverse to the enhanced expression of matrix metalloproteinases (MMPs), the development of aortic aneurysm is lower in diabetic population. We examined the hypothesis that DM-induced alteration of metal ion levels declines the activity of MMPs to decrease aortic aneurysm risk. Methods & ResultsBy culturing vascular smooth muscle cells (VSMCs) or macrophages with different concentrations of glucose in the medium, we confirmed that high glucose significantly increased the expression of fibronectin and CTGF in VSMCs, and induced MMP2 expression and MMP9 secretion in macrophages. We also established an abdominal aortic aneurysm model in streptozotocin-induced diabetic mice and evaluated aneurysm development six weeks later. Compared to the healthy controls, diabetic mice had significantly lower levels of Zn2+ and Mg2+ in serum and developed significantly smaller sizes of aneurysms with higher expression of fibronectin and CTGF; but dietary zinc supplementation to diabetic mice effectively neutralized these differences. Gelatin zymography assay indicated that the enzymatic digestion activity of MMP2 was changed under different concentrations of ZnSO4 and MgSO4. Clinical data analysis also confirmed that DM, serum Zn2+ level, and aortic aneurysm risk closely correlated with each other. ConclusionIt seems that DM-induced alteration of metal ion levels declines the activity of MMPs to negate aortic aneurysm development. Our data provide novel mechanistical insight and therapeutic strategy for aortic aneurysms.

Ionizing radiation inhibits zebrafish embryo hatching through induction of tissue inhibitors of metalloproteinases (TIMPs) expression.

Ionizing radiation (IR) has garnered growing attention because of its biological effects on aquatic organisms and humans. Here, we identify the most impacted organs and uncover the molecular mechanisms causing the changes in the context of vertebrate development using single-cell RNA sequencing. Alterations in cellular composition and biological functions were explored using transcriptomic profiling of zebrafish embryos exposed to 5 Gy. Single-cell RNA sequencing analyses unveiled notable shifts in the proportions of brain/central nervous system and hatching gland clusters. Although IR exposure led to increased expression of hatching enzymes, a significant but mild delay in hatching was observed following 5 Gy IR exposure. Gene Ontology analysis showed an increased expression of tissue inhibitors of metalloproteinases (TIMPs), known as matrix metalloproteinase inhibitors, which was confirmed via whole-mount in situ hybridization. Correlation analysis linked TIMPs to transcription factors cebpb and cebpd, which were significantly correlated post-IR exposure. Although no morphological changes were observed in some organs, including the brain, the study reveals substantial alterations in developing vertebrates. Notably, despite increased hatching enzymes, elevated TIMPs in the hatching gland suggest a regulatory mechanism impacting hatching activity. This research contributes to comprehending the ecological repercussions of IR exposure, emphasizing the importance of safety measures for aquatic ecosystems and overall environmental health.

Synthetic Protein-to-DNA Input Exchange for Protease Activity Detection Using CRISPR-Cas12a.

We present a novel activity-based detection strategy for matrix metalloproteinase 2 (MMP2), a critical cancer protease biomarker, leveraging a mechanism responsive to the proteolytic activity of MMP2 and its integration with CRISPR-Cas12a-assisted signal amplification. We designed a chemical translator comprising two functional units─a peptide and a peptide nucleic acid (PNA), fused together. The peptide presents the substrate of MMP2, while the PNA serves as a nucleic acid output for subsequent processing. This chemical translator was immobilized on micrometer magnetic beads as a physical support for an activity-based assay. We incorporated into our design a single-stranded DNA partially hybridized with the PNA sequence and bearing a region complementary to the RNA guide of CRISPR-Cas12a. The target-induced nuclease activity of Cas12a results in the degradation of FRET-labeled DNA reporters and amplified fluorescence signal, enabling the detection of MMP2 in the low picomolar range, showing a limit of detection of 72 pg/mL. This study provides new design principles for a broader applicability of CRISPR-Cas-based biosensing.

The Inhibitory Effect of Hedera helix and Coptidis Rhizome Mixture in the Pathogenesis of Laryngopharyngeal Reflux: Cleavage of E-Cadherin in Acid-Exposed Primary Human Pharyngeal Epithelial Cells.

Laryngopharyngeal reflux disease (LPRD) is a prevalent upper airway disorder characterized by inflammation and epithelial damage due to the backflow of gastric contents. Current treatments, primarily proton pump inhibitors (PPIs), often show variable efficacy, necessitating the exploration of alternative or adjunctive therapies. This study investigates the therapeutic potential of a mixture of Hedera helix and Coptidis rhizome (HHCR) in mitigating the pathophysiological mechanisms of LPRD. Using an in vitro model of human pharyngeal epithelial cells exposed to acidic conditions, we observed that acid exposure significantly increased the expression of adenosine A3 receptor (adenosine A3) and matrix metalloproteinase-7 (MMP-7), leading to E-cadherin cleavage and compromised epithelial integrity. Treatment with the HHCR mixture effectively suppressed adenosine A3 expression and MMP-7 activity, thereby reducing E-cadherin cleavage and preserving cellular cohesion. These results highlight the HHCR mixture's ability to modulate the adenosine A3-MMP-7-E-cadherin pathway, suggesting its potential as a valuable adjunctive therapy for LPRD, particularly for patients unresponsive to conventional PPI treatment. This study provides new insights into the molecular interactions involved in LPRD and supports further clinical evaluation of HHCR as a complementary treatment option.

Rosuvastatin activates autophagy via inhibition of the Akt/mTOR axis in vascular smooth muscle cells.

The proliferation and migration of vascular smooth muscle cells (VSMCs) are key contributors to the development of atherosclerosis and restenosis. We investigated the impact of rosuvastatin (RSV) on platelet-derived growth factor (PDGF)-BB-induced proliferation and migration of VSMCs, with a focus on the Akt/mTOR-autophagy signaling pathways. The cytotoxicity of RSV was assessed using MTT and annexin V staining, while the proliferation and migration capabilities of PDGF-BB-induced VSMCs were evaluated using MTT and cell migration assays. Confocal microscopy was employed to examine autophagic cell images, and protein expressions were analyzed via Western blotting. Our key findings revealed that RSV inhibited PDGF-BB-induced proliferation and migration of VSMCs, significantly reducing the expression of proliferating cell nuclear antigen and matrix metalloproteinase-2, which are crucial for these processes. RSV also enhanced autophagy in PDGF-BB-stimulated cells by inducing the maturation of microtubule-associated protein light chain 3 and increasing the expression of Beclin-1, autophagy related (Atg)3, Atg5, and Atg7. The regulatory effects of RSV on PDGF-BB-induced autophagy, proliferation, and migration were associated with the suppression of the Akt/mTOR signaling pathway. These findings suggest that RSV may have potential therapeutic benefits in preventing and treating vascular diseases by targeting the Akt/mTOR pathway and inducing autophagy.

Exiguolysin, a Novel Thermolysin (M4) Peptidase from Exiguobacterium oxidotolerans.

This study details a comprehensive biochemical and structural characterization of exiguolysin, a novel thermolysin-like, caseinolytic peptidase secreted by a marine isolate of Exiguobacterium oxidotolerans strain BW26. Exiguolysin demonstrated optimal proteolytic activity at 37 °C and pH 3, retaining 85% activity at 50 °C, highlighting its potential stability under broad reaction conditions. SDS-PAGE and LC-MS analysis identified the enzyme as a 32 kDa M4-family metalloprotease. Exiguolysin activity was inhibited by 1,10-phenanthroline, confirming its dependence on metal ions for activity. Zymographic analysis and substrate specificity assays revealed selective hydrolysis of matrix metalloproteinase (MMP) substrates but no activity against elastase substrates. Analysis of the predicted gene sequence and structural predictions using AlphaFold identified the presence and position of HEXXH and Glu-Xaa-Xaa-Xaa-Asp motifs, crucial for zinc binding and catalytic activity, characteristic of 'Glu-zincins' and members of the M4 peptidase family. High-throughput screening of a 20 × 20 N-alpha mercaptoamide dipeptide inhibitor library against exiguolysin identified SH-CH2-CO-Met-Tyr-NH2 as the most potent inhibitor, with a Ki of 1.95 μM. Notably, exiguolysin selectively inhibited thrombin-induced PAR-1 activation in PC-3 cells, potentially indicating a potential mechanism of virulence in modulating PAR-1 signalling during infection by disarming PARs. This is the first detailed characterization of a peptidase of the M4 (thermolysin) family in the genus Exiguobacterium which may have industrial application potential and relevance as a putative virulence factor.