Matrix metalloproteinases and tissue inhibitors of metalloproteinases: structure, function, and biochemistry

Effects of in vitro cytochalasin D and hypoxia on mitochondrial energetics and biogenesis, cell signal status and actin/tubulin/Hsp/MMP entity in air-breathing fish heart

The cardiac actin cytoskeleton has a dynamic pattern of polymerisation. It is uncertain how far actin destabilisation impacts mitochondrial energetics and biogenesis, cell signal status, and structural entities in cardiomyocytes, particularly in hypoxic conditions. We thus tested the in vitro action of cytochalasin D (Cyt D), an inhibitor of actin polymerisation, in hypoxic ventricular explants to elucidate the role of the actin in mitochondrial energetics and biogenesis, cell signals and actin/tubulin/hsps/MMPs dynamics in hypoxic air-breathing fish hearts. The COX activity increased upon Cyt D exposure, whereas hypoxia lowered COX and SDH activities but increased LDH activity. The ROS increased, and NO decreased by Cyt D. COX and LDH activities, and NO content reversed after Cyt D exposure in hypoxic hearts. Cyt D exposure upregulated actin isoform expression (Actc1 and Actb1) but downregulated tubulin isoform (Tedc1). Hypoxia upregulated actin (Acta1a, Actb1, Actb2, Actc1a) tubulin (Tuba, Tubb5, Tedc1, Tubd1) and hsp (Hspa5, Hspa9, Hspa12a, Hspa14, Hspd1, Hsp90) isoform transcript expression and Cyt D in hypoxic hearts reversed these isoform's expression. Hypoxia upregulated Mmp2 and 9 transcript expressions but downregulated Mfn1, Fis1, Nfkb1, Prkacaa, and Aktip expressions, and Cyt D exposure reversed almost all these markers in hypoxic hearts. The data provide novel evidence for the mechanistic role of actin in integrating mitochondrial energetics and biogenesis, cell signal status and actin/tubulin/Hsp/MMP entity, indicating its critical cardioprotective role in defending against hypoxia. Besides proposing an air-breathing fish heart as a model, the study further brings the therapeutic potential of Cyt D towards hypoxia intervention.

Multi-omics analysis of synovial tissue and fluid reveals differentially expressed proteins and metabolites in osteoarthritis

BACKGROUND

Knee osteoarthritis is a common degenerative joint disease involving multiple pathological processes, including energy metabolism, cartilage repair, and osteogenesis. To investigate the alterations in critical metabolic pathways and differential proteins in osteoarthritis patients through metabolomic and proteomic analyses and to explore the potential mechanisms underlying synovial osteogenesis during osteoarthritis progression.

METHODS

Metabolomics was used to analyze metabolites in the synovial fluid and synovium of osteoarthritis patients (osteoarthritis group: 10; control group: 10), whereas proteomics was used to examine differential protein expression. Alkaline phosphatase activity was assessed to evaluate osteogenesis.

RESULTS

Upregulation of the tricarboxylic acid cycle: Significant upregulation of the tricarboxylic acid cycle in the synovial fluid and synovium of osteoarthritis patients indicated increased energy metabolism and cartilage repair activity. Arginine metabolism and collagen degradation: Elevated levels of ornithine, proline, and hydroxyproline in the synovial fluid reflect active collagen degradation and metabolism, contributing to joint cartilage breakdown. Abnormal Phenylalanine Metabolism: Increased phenylalanine and tyrosine metabolite levels in osteoarthritis patients suggest their involvement in cartilage destruction and osteoarthritis progression. Synovial osteogenesis: Increased expression of type I collagen in the synovium and elevated alkaline phosphatase activity confirmed the occurrence of osteogenesis, potentially driven by the differentiation of synovial fibroblasts, mesenchymal stem cells, and hypertrophic chondrocytes. Relationships between differential proteins and osteogenesis: FN1 and TGFBI are closely associated with synovial osteogenesis, while the upregulation of energy metabolism pathways provides the energy source for osteogenic transformation.

CONCLUSIONS

Alterations in energy metabolism, cartilage repair, and osteogenic mechanisms are critical. The related metabolites and proteins have potential as diagnostic and therapeutic targets for osteoarthritis.

Antibiofilm properties, cytotoxicity, and effect on protease activity of antibiotics and EGCG-based medications for endodontic purposes

OBJECTIVE

To evaluate the effect of two intracanal medications (IM) containing epigallocatechin-3-gallate (EGCG) with fosfomycin (FOSFO) and a triantibiotic combination of metronidazole, ciprofloxacin and fosfomycin (TRI), compared to controls calcium hydroxide (CH), all dissolved in polyethylene glycol 400 (PEG) on multispecies biofilms, fibroblast toxicity and on collagenolytic and gelatinolytic activities detected in radicular dentin.

METHODS

The antibiofilm effect and cytotoxicity of medications containing EGCG + FOSFO, TRI or CH were evaluated on multispecies biofilms formed in bovine root dentin specimens by confocal microscopy and on fibroblasts by resazurin assays, respectively. The inhibition of protease activity of each IM was evaluated by measuring collagenolytic enzyme activity by ELISA (Enzyme-linked immunosorbent assay) and gelatinolytic activity by metalloproteinases (MMPs) using in situ zymography in radicular dentin specimens.

RESULTS

PEG containing EGCG+FOSFO, PEG+TRI, and PEG+CH significantly reduced multispecies biofilms in radicular dentin tubules. At the concentrations tested, those IM were not toxic to fibroblasts. Additionally, all IM presented anti-collagenolytic activity by reducing telopeptide fragments released from radicular dentin compared to PEG carrier and water controls. In situ gelatinolytic activity, assessed via fluorescence levels, was significantly lower in radicular dentin adjacent to PEG containing CH, EGCG+FOSFO, or TRI compared to PEG and water controls.

CONCLUSION

EGCG+FOSFO and TRI in PEG-400 exhibited antibiofilm, anti-collagenolytic and anti-gelatinolytic properties at concentrations that were non-toxic to fibroblasts, making them feasible intracanal medications for endodontic applications.

CLINICAL SIGNIFICANCE

EGCG-based medications enhance the efficacy of endodontic treatment by providing antibiofilm, anti-collagenolytic, and anti-gelatinolytic properties, contributing to the preservation of root structure and improved treatment outcomes.

Comparative effects of various extracellular vesicle subpopulations derived from clonal mesenchymal stromal cells on cultured fibroblasts in wound healing-related process

INTRODUCTION

Non-healing wounds pose significant challenges and require effective therapeutic interventions. Extracellular vesicles (EVs) have emerged as promising cell-free therapeutic agents in tissue regeneration. However, the functional differences between different subpopulations of EVs in wound healing remain understudied. This study aimed to evaluate the effects of two distinct subpopulations of clonal mesenchymal stromal cells (cMSC)-derived EVs (cMSC-EVs), namely 20 K and 110K-cMSC-EVs, primarily on in vitro wound healing process, providing fast and cost-effective alternatives to animal models.

METHODS

In vitro assays were conducted to compare the effects of 20 K and 110K-cMSC-EVs, isolated through high-speed centrifugation and differential ultracentrifugation, respectively. For evaluation the main mechanisms of wound healing, including cell proliferation, cell migration, angiogenesis, and contraction. Human dermal fibroblasts (HDF) were considered as the main cells for analysis of these procedures. Moreover, gene expression analysis was performed to assess the impact of these EV subpopulations on the related process of wound healing on HDF.

RESULTS

The results demonstrated that both 20 K and 110K-cMSC-EVs exhibited beneficial effects on cell proliferation, cell migration, angiogenesis, and gel contraction. RT-qPCR revealed that both EV types downregulated interleukin 6 (IL6), induced proliferation by upregulating proliferating cell nuclear antigen (PCNA), and regulated remodeling by upregulating matrix metallopeptidase 1 (MMP1) and downregulating collagen type 1 (COL1).

DISCUSSION

This study highlights the effects of both 20 K and 110K-cMSC-EVs on the potency of HDFs in wound healing-related process. As the notable finding, 20K-cMSC-EVs offer a more feasible and cost-effective subpopulation for isolation and follow the GMP standard, recommended to utilize this fraction for therapeutic application.

Vimentin intermediate filaments coordinate actin stress fibers and podosomes to determine the extracellular matrix degradation by macrophages

Macrophages possess the capacity to degrade extracellular matrix (ECM), but the specific roles of different cytoskeletal structures in controlling this process are incompletely understood. Here, we report that the inward flow of actin stress fibers delivers endocytosed ECM for lysosomal elimination, replenishing the pool of enzymes for extracellular ECM hydrolysis in actin-rich podosomes. Vimentin deficiency disrupted the balance between stress fibers and podosomes, impairing ECM degradation through integrin CD11b in THP-1 macrophages. In lung adenocarcinoma patient samples, M2-type macrophages exhibit a tighter podosome organization, surrounded by compact vimentin filaments, than M1-type. In vitro experiments verified that the invasion ability of A549 lung carcinoma cells was enhanced when accompanied by wild type, but not vimentin knockout M2-type THP-1, macrophages. Subcutaneous injections of macrophages and tumor cells in nude mice showed that vimentin in macrophages can reduce tumor collagen fibers. Together, our findings provide insights into the cytoskeletal dynamics governing macrophage ECM degradation.

Tissue-specific and spatially dependent metabolic signatures perturbed by injury in skeletally mature male and female mice

Joint injury is a risk factor for post-traumatic osteoarthritis. However, metabolic and microarchitectural changes within the joint post-injury in both sexes remain unexplored. This study identified tissue-specific and spatially-dependent metabolic signatures in male and female mice using matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI) and LC-MS metabolomics. Male and female C57Bl/6J mice were subjected to non-invasive joint injury. Eight days post-injury, serum, synovial fluid, and whole joints were collected for metabolomics. Analyses compared between injured, contralateral, and naïve mice, revealing local and systemic responses. Data indicate sex influences metabolic profiles across all tissues, particularly amino acid, purine, and pyrimidine metabolism. MALDI-MSI generated 2D ion images of bone, the joint interface, and bone marrow, highlighting increased lipid species in injured limbs, suggesting physiological changes across injured joints at metabolic and spatial levels. Together, these findings reveal significant metabolic changes after injury, with notable sex differences.

Myeloid Cell mPGES-1 Deletion Attenuates Calcium Phosphate-induced Abdominal Aortic Aneurysm in Male Mice

Microsomal PGE2 synthase (mPGES)-1 is the key enzyme responsible for synthesizing inflammatory prostaglandin E2 (PGE2). Our previous studies have shown that deletion mPGES-1 in myeloid cells hinders atherogenesis, suppresses vascular proliferative response to injury and enhances survival after myocardial infarction. Here we aimed to further explore the influence of myeloid cell mPGES-1 deletion in abdominal aortic aneurysm (AAA) formation. The AAA was triggered by applying 0.5 M calcium phosphate (CaPO4) to the infrarenal aorta of both myeloid mPGES-1 knockout (Mac-mPGES-1-KO) and their littermate control Mac-mPGES-1-WT mice. AAA induction was assessed by calculating the expansion of the infrarenal aortic diameter 4 weeks after CaPO4 application. The maximum diameters of the aortas were measured by morphometry and the mean maximal diameters were calculated. Paraffin sections of the infrarenal aortas were examined for morphological analysis and immunohistochemical staining. The results showed that myeloid cell mPGES-1 deletion significantly mitigated AAA formation, including reducing expansion of the infrarenal aorta, preventing elastic lamellar degradation, and decreasing aortic calcium deposition. Immunohistochemical staining further indicated that macrophage infiltration and matrix metalloproteinase 2 (MMP2) expression was attenuated in the Mac-mPGES-1-KO aortas. Consistently, in vitro experiments showed that expression of pro-inflammatory cytokines and MMPs was significantly reduced when mPGES-1 was lacking in the primary cultured peritoneal macrophages. These data altogether demonstrated that deletion of mPGES-1 in myeloid cells may attenuate AAA formation and targeting myeloid cell mPGES-1 could potentially offer an effective strategy for the treatment and prevention of vascular inflammatory diseases.

The evolution of adhesive dentistry: From etch-and-rinse to universal bonding systems

OBJECTIVES

This review aimed at presenting the mechanisms and pitfalls of adhesion to enamel and dentin, advances in the materials science and in the development of strategies to improve hybrid layer (HL) longevity.

METHODS

Search of the literature was performed on PubMed, Scopus and Web of Science with keywords related to the structure of the dental substrate, HL degradation mechanisms and strategies to contrast them.

RESULTS

Albeit the advances in the dental materials' properties, HL degradation is still a relevant and current issue in adhesive dentistry. However, adhesive materials have become more resistant and less operator sensitive, and good adhesion is currently in the hands of every practitioner. Numerous novel strategies are being developed, able to improve the resistance of adhesive resins to degradation, their ability to infiltrate and chemically bond to dentin, to remove the unbound/residual water within the HL, reinforce the dentin collagen matrix, and inhibit endogenous metalloproteinases. Many of the strategies have turned to nature in search for powerful biomodifying compounds, and for the inspiration as to mimic naturally occurring regenerative processes.

SIGNIFICANCE

Extensive knowledge on the structure of the dental substrate and the complexity of adhesion to dentin has led to the development of improved formulations of dental adhesives and numerous valid strategies to improve the strength and longevity of the HL. Nevertheless, for many of them the road from bench to chairside still seems long. We encourage practitioners to know their materials well and use the strategies readily available to them.

FFA intervention on LO2 cells mediates SNX-10 synthesis and regulates MMP9 secretion in LX2 cells via TGF-β1

BACKGROUND

Metabolic-associated fatty liver disease (MAFLD) is a public health concern. Transforming growth factor-β1(TGF-β1) plays an important regulatory role in multiple MAFLD stages, as it can promote the expression of matrix metalloproteinase-9 (MMP9) and promote liver fibrosis. Sorting nexin protein-10 (SNX-10) may be involved in the occurrence and development of fatty liver disease.

METHODS

Free fatty acids (FFA) treatment was used to simulate the cellular lipid deposition stage of MAFLD and the interactions between cells were simulated via LX2 and LO2 coculture. The molecular interaction between the two cell types was studied via ELISA, immunoprecipitation, qPCR, and western blotting.

RESULTS

In FFA-treated LO2 cells, intracellular TGF-β1 expression increased as lipid deposition increased. FFA-treated LO2 cells promoted the expression and secretion of MMP9 by LX2 cells through paracrine pathways. MMP9 secretion decreased with decreasing SNX-10 expression in LX2 cells. The interaction between MMP9 and SNX-10 was confirmed by coimmunoprecipitation. TGF-β1 promoted the synthesis of SNX-10 through the p38 MAPK pathway, and SNX-10 affected the secretion of MMP9 through protein interactions, thereby affecting the development of liver fibrosis.

CONCLUSIONS

FFA induced lipid deposition in LO2 cells, and TGF-β1 mediated the p38 MAPK pathway to promote SNX-10 synthesis and stimulate MMP9 secretion, thereby regulating the involvement of LX2 in the process of liver fibrosis.

Myricetin Modulates Matrix Metalloproteinases Expression Induced by TEGDMA in Human Odontoblast-Like Cells

The activity of matrix metalloproteinases (MMPs) plays a crucial role in the aging of the resin-dentin interface. The in situ action of MMP-2 and MMP-9 has been confirmed in the process of dentin-collagen degradation. However, the involvement of dental pulp cells in MMP secretion as a response to oxidative stress induced by contact with resin monomers has not been fully elucidated. Myricetin (MYR), like proanthocyanidin (PAC), has antioxidant properties and may help prevent extracellular matrix degradation. The objective was to evaluate the effect of MYR on the MMP expression and activity in response to reactive oxygen species (ROS) increase induced by triethylene glycol dimethacrylate (TEGDMA) in human odontoblast-like cells (hOLCs). hOLCs differentiated from dental pulp mesenchymal stem cells were exposed to TEGDMA released from dentin blocks using a barrier model with transwell inserts for 18, 24, and 36 h. Intracellular oxidation was evaluated using the 2',7'-dichlorofluorescein probe. The effect of 600 μM MYR on the MMP-2 and MMP-9 expression was determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The extracellular MMP levels were quantified using enzyme-linked immunosorbent assay, and their activation by means of a proteolytic fluorometric assay. The results were analyzed by one-way analysis of variance and Tukey's post hoc test, p ≤ 0.05. TEGDMA exposure increased intracellular ROS and upregulated MMP-2 and MMP-9 mRNA in hOLCs (p < 0.001). The levels of MMPs increased significantly 24 h after TEGDMA exposure (p = 0.013). These secreted proteases exhibited high activation ability. MYR reduced ROS production and downregulated MMP expression and activity at both mRNA and protein levels, similar to the effect found for PAC, which was used as a control. A relationship was observed between MMP-2 and MMP-9 expression, secretion, and early activation with ROS increase due to TEGDMA exposure. MYR showed potential as a therapeutic strategy to control MMP expression and modulate redox imbalance, offering a protective effect on cellular response.

The interplay of senescence and MMPs in myocardial infarction: implications for cardiac aging and therapeutics

Aging is associated with a marked increase in cardiovascular diseases, such as myocardial infarction (MI). Cellular senescence is also a crucial factor in the development of age-related MI. Matrix metalloproteinases (MMPs) interaction with cellular senescence is a critical determinant of MI development and outcomes, most notably in the aged heart. After experiencing a heart attack, senescent cells exhibit a Senescence-Associated Secretory Phenotype (SASP) and are involved in tissue regeneration and chronic inflammation. MMPs are necessary for extracellular matrix proteolysis and have a biphasic effect, promoting early heart healing and detrimental change if overexpressed shortly. This review analyses the complex connection between senescence and MMPs in MI and how it influences elderly cardiac performance. Critical findings suggest that increasing cellular senescence in aged hearts elevates MMP activity and aggravates extended ventricular remodeling and dysfunction. Additionally, we explore potential therapeutics that address MMPs and senescence to enhance old MI patient myocardial performance and regeneration.

Bond strength to eroded dentin as per chlorhexidine use for controlling erosive wear or interface aging: an 18-month assay

The aim of this study was to assess the effect of a chlorhexidine digluconate solution (CHX) applied as an antiproteolytic agent for controlling erosive tooth wear or as part of the adhesive treatment on long-term bond strength to eroded dentin. Dentin specimens were abraded with a 600-grit silicon carbide (SiC) paper for 1 min (sound dentin - S), subsequently treated with 2% CHX for 1 min (with excess removed, followed by a 6-hour rest), and eroded by exposure to Coca-Cola for 5 min, three times a day, for 5 days (CHX-treated and eroded dentin - CHXE), or only eroded (eroded dentin - E). The specimens were acid-etched (15 s), rinsed (30 s), dried (15 s), and rehydrated with 1.5 μL of distilled water for 1 min, with excess removed (control - S.C/CHXE.C/E.C) or 2% CHX (S.CHX/CHXE.CHX/E.CHX). Adper Single Bond 2 was scrubbed twice on the surface for 15 s each and then light-cured for 10 s, and resin composite cores were built up. Specimens were sectioned into beams and microtensile bond strength was tested (μTBS; 0.5 mm/min) immediately or after 18-month aging. Failure modes were analyzed using a digital microscope. Data (μTBS/MPa) were analyzed by three-way ANOVA, followed by Tukey's test (α = 0.05). μTBS to E and CHXE, irrespective of the rehydration solution and aging period, were equivalent to each other and lower than that to S. CHX as the rehydration solution reduced immediate and long-term µTBS to S. Aging reduced μTBS. By controlling tooth wear or interface aging, CHX could not influence long-term bonding to eroded dentin.

Galectin-3 disrupts tight junctions of airway epithelial cell monolayers by inducing expression and release of matrix metalloproteinases upon influenza A infection

Galectins are β-galactosyl-binding lectins with key roles in early development, immune regulation, and infectious disease. Influenza A virus (IAV) infects the airway epithelia, and in severe cases may lead to bacterial superinfections and hypercytokinemia, and eventually, to acute respiratory distress syndrome (ARDS) through the breakdown of airway barriers. The detailed mechanisms involved, however, remain poorly understood. Our prior in vivo studies in a murine model system revealed that upon experimental IAV and pneumococcal primary and secondary challenges, respectively, galectin-1 and galectin-3 (Gal-3) are released into the airway and bind to the epithelium that has been desialylated by the viral neuraminidase, contributing to secondary bacterial infection and hypercytokinemia leading to the clinical decline and death of the animals. Here we report the results of in vitro studies that reveal the role of the extracellular Gal-3 in additional detrimental effects on the host by disrupting the integrity of the airway epithelial barrier. IAV infection of the human airway epithelia cell line A549 increased release of Gal-3 and its binding to the A549 desialylated cell surface, notably to the transmembrane signaling receptors CD147 and integrin-β1. Addition of recombinant Gal-3 to A549 monolayers resulted in enhanced expression and release of matrix metalloproteinases, leading to disruption of cell-cell tight junctions, and a significant increase in paracellular permeability. This study reveals a critical mechanism involving Gal-3 that may significantly contribute to the severity of IAV infections by promoting disruption of tight junctions and enhanced permeability of the airway epithelia, potentially leading to lung edema and ARDS.

Mechanisms Underlying Vascular Inflammaging: Current Insights and Potential Treatment Approaches

Inflammaging refers to chronic, low-grade inflammation that becomes more common with age and plays a central role in the pathophysiology of various vascular diseases. Key inflammatory mediators involved in inflammaging contribute to endothelial dysfunction and accelerate the progression of atherosclerosis. In addition, specific pathological mechanisms and the role of inflammasomes have emerged as critical drivers of immune responses within the vasculature. A comprehensive understanding of these processes may lead to innovative treatment strategies that could significantly improve the management of age-related vascular diseases. Emerging therapeutic approaches, including cytokine inhibitors, senolytics, and specialized pro-resolving mediators, aim to counteract inflammaging and restore vascular health. This review seeks to provide an in-depth exploration of the molecular pathways underlying vascular inflammaging and highlight potential therapeutic interventions.

Identification of potential MMP-8 inhibitors through virtual screening of natural product databases

Matrix metalloproteinase-8 (MMP-8), a type II collagenase, is a key enzyme in the degradation of collagens and is implicated in various pathological processes, making it a promising target for drug discovery. Despite advancements in the development of MMP-8 inhibitors, concerns over potential adverse effects persist. This study aims to address these concerns by focusing on the development of novel compounds with improved safety profiles while maintaining efficacy. In this study, we employed a computational approach to screen potent and safe inhibitors of MMP-8 from the Natural Product Activity and Species Source Database (NPASS). Initially, we constructed a pharmacophore model based on the crystal structure of the MMP-8-FIN complex (PDB ID: 4EY6) utilizing the Pharmit tool. This model then guided the selection of 44 promising molecules from NPASS, setting the stage for further analysis and evaluation. We comprehensively evaluated their drug-likeness and toxicity profiles. Molecules 21, 4, and 44 were identified as potentially effective MMP-8 inhibitors through a robust pipeline that included ADMET profiling, molecular docking, and molecular dynamics simulations. Notably, molecule 21 stood out for its low toxicity, high binding stability, and favorable ADMET profile, while molecule 44 demonstrated excellent affinity. These compounds offer structural novelty compared to known MMP-8 inhibitors. These computational results can be combined with in vitro experiments in the future to validate their activity and safety. These findings provide an important reference for drug design of MMP-8 inhibitors.

MMP-9 and TIMPs profiles in sulfur mustard-exposed individuals with serious lung complications

Sulfur mustard (SM), a chemical weapon used in the Iraq-Iran war, can pose severe health risks, especially to the lungs. Dysregulation of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) have been implicated in various inflammatory lung diseases. This study compares the levels of MMPs and TIMPs in the serum and sputum of veterans with serious lung complications to a control group. Serum and sputum samples were collected and analyzed using the ELISA sandwich method. Differences between SM-exposed and control groups were assessed statistically. The serum levels of TIMP-4 and MMP-9/TIMP-4 were significantly lower and higher in the SM-exposed group respectively compared to the control group. In SM-exposed individuals resembling Bronchiolitis Obliterans (BO), Chronic Bronchitis (CB), and Asthma, TIMP-4 levels were lower than controls, while TIMP-2 levels were higher in those with CB. Although the increased TIMP-2 levels in these patients align with COPD studies, differences were observed in other factors with COPD and asthma-related MMP-9 and TIMP-4 findings. Assessment of serum levels of these factors based on severity reveals lower MMP-9/TIMP-4 levels in the severe group compared to the mild-moderate group. Individuals exposed to SM exhibit distinct MMP and TIMP profiles, with significantly lower TIMP-4 levels and higher MMP-9/TIMP-4 ratios, compared to controls. These profiles vary across different lung conditions, indicating a unique disease mechanism in SM-exposed individuals. This distinctive profile supports the classification of this condition as 'Mustard Lung.' Further research is needed to elucidate these mechanisms for targeted therapeutic interventions.

Exploring the effectiveness of doxycycline in restorative dentistry: a systematic review of in vitro studies

This systematic review evaluated the efficacy of doxycycline in MMP inhibition, its antibacterial action, and other properties relevant to dental materials testing. The study protocol was registered at the Open Science Framework ( https://doi.org/10.17605/OSF.IO/ZVK2T ). Reporting was based on PRISMA statement. The search was carried out in the databases: PubMed, Scopus, Web of Science, Embase, Lilacs, and Google Scholar. Articles were restricted to Portuguese, English, and Spanish, with no date limit. In vitro studies were selected based on the following outcomes: DOX antibacterial and anti-metalloproteinase activity and its influence in physico-chemical properties. Two researchers independently selected the articles and collected the data. Of 1507 documents, 82 were fully evaluated and 21 were included. Different forms of doxycycline incorporation were found, both as free form and incorporated into carrier agents. The drug was tested as primers, incorporated in adhesive or glass ionomer cement. No studies were found that evaluated its incorporation in resin composite or resin cement. The results confirmed the therapeutic properties of the medication, with more significant results when incorporated in an adhesive. However, although promising, the use of this substance requires standardization in application methods and adopted concentrations, allowing for more direct comparisons between studies. Furthermore, long-term studies are interesting to conduct, ensuring biocompatibility and complete understanding of long-term effects on dental materials.

Advances focusing on the application of decellularization methods in tendon-bone healing

BACKGROUND

The tendon or ligament is attached to the bone by a triphasic but continuous area of heterogeneous tissue called the tendon-bone interface (TBI). The rapid and functional regeneration of TBI is challenging owing to its complex composition and difficulty in self-healing. The development of new technologies, such as decellularization, has shown promise in the regeneration of TBI. Several ex vivo and in vivo studies have shown that decellularized grafts and decellularized biomaterial scaffolds achieved better efficacy in enhancing TBI healing. However further information on the type of review that is available is needed.

AIM OF THE REVIEW

In this review, we discuss the current application of decellularization biomaterials in promoting TBI healing and the possible mechanisms involved. With this work, we would like to reveal how tissues or biomaterials that have been decellularized can improve tendon-bone healing and to provide a theoretical basis for future related studies.

KEY SCIENTIFIC CONCEPTS OF THE REVIEW

Decellularization is an emerging technology that utilizes various chemical, enzymatic and/or physical strategies to remove cellular components from tissues while retaining the structure and composition of the extracellular matrix (ECM). After decellularization, the cellular components of the tissue that cause an immune response are removed, while various biologically active biofactors are retained. This review further explores how tissues or biomaterials that have been decellularized improve TBI healing.

Single Nucleotide Polymorphisms and Tendon/Ligament Injuries in Athletes: A Systematic Review and Meta-analysis

This systematic review and meta-analysis aimed to identify the association between genetic polymorphisms and tendon and ligament injuries in adolescent and adult athletes of multiple competition sports. The PubMed, Web of Science, EBSCO, Cochrane Library, and MEDLINE databases were searched until July 7, 2023. Eligible articles included genetic studies on tendon and ligament injuries and comparisons between injured and non-injured athletes. This review included 31 articles, comprising 1,687 injury cases and 2,227 controls, from a meta-analysis of 12 articles. We identified 144 candidate gene polymorphisms (only single nucleotide polymorphisms were identified). The meta-analyses included vascular endothelial growth factor A (VEGFA) rs699947, collagen type I alpha 1 rs1800012, collagen type V alpha 1 rs12722, and matrix metalloproteinase 3 rs679620. The VEGFA rs699947 polymorphism showed a lower risk of injuries in athletes with the C allele ([C vs. A]: OR=0.80, 95% CI: 0.65-0.98, I 2 =3.82%, p=0.03). The risk of these injuries were not affected by other polymorphisms. In conclusion, the VEGFA rs699947 polymorphism is associated with the risk of tendon and ligament injuries in athletes. This study provides insights into genetic variations that contribute to our understanding of the risk factors for such injuries in athletes.

The effects of coagulation factors on the risk of autoimmune diseases: A Mendelian randomization study

The objective of this study was to investigate the potential causal relationship between coagulation factors and autoimmune diseases (ADs). We employed Mendelian randomization to investigate the associations between selected 7 coagulation factors and 10 ADs, leveraging genetic variants as instrumental variables to assess causal relationships between exposures of interest and outcomes. Within the scope of this investigation, coagulation factors were designated as the exposure source, while ADs were observed to manifest as the consequent outcome. Our analysis using the inverse-variance weighted (IVW) method revealed that Factor VIII (FVIII) (P = .0067) exhibited significant causal associations with a reduced risk of multiple sclerosis. In contrast, fibrinogen (P = .0004) was associated with an increased risk of multiple sclerosis. The analysis also indicated that activated partial thromboplastin time (P = .0047) was implicated in elevating the risk of urticaria. The results also showed that protein C (P = .0188) was inversely associated with the risk of systemic lupus erythematosus. The results unveiled a significant positive correlation between fibrinogen (P = .0318) and the risk of rheumatoid arthritis. Similarly, Factor VII (P = .0119), FVIII (P = .0141), and von Willebrand Factor (P = .0494) were also found to be positively associated with the risk of inflammatory bowel disease. The IVW analysis demonstrated a causal relationship between von Willebrand Factor (P = .0316) and FVIII (P = .0408) and a decreased risk of primary sclerosing cholangitis. IVW results confirmed that protein C (P = .0409) had a protective effect on vitiligo. No significant associations were found between psoriatic arthritis, rosacea, and the 7 coagulation factors in this study. This is of significant importance for advancing the prevention, diagnosis, and treatment of ADs.

The Influence of Bariatric Surgery on Matrix Metalloproteinase Plasma Levels in Patients with Type 2 Diabetes Mellitus

BACKGROUND

Bariatric surgery is a safe and effective procedure for treating obesity and metabolic conditions such as type 2 diabetes mellitus (T2DM). Remodeling of the extracellular matrix (ECM) supports adipose tissue expansion and its metabolic activity, where matrix metalloproteinases (MMPs) play a key role in ECM regulation. The MMPs, particularly MMP-2 and MMP-9, are elevated in patients with morbid obesity, metabolic syndrome, and T2DM.

OBJECTIVES

To evaluate the effect of weight loss in bariatric surgery patients using oxidative stress markers and to compare MMP levels in patients undergoing bariatric surgery.

METHODS

This was a prospective, controlled study including 45 morbidly obese patients with T2DM (BMI > 35 kg/m2) who underwent RYGB (n = 24) or VG (n = 21). Weight loss was assessed through anthropometric measurements (weight, height, BMI). MMP-2 and MMP-9 levels were measured preoperatively and at 3 and 12 months postoperatively.

RESULTS

Significant and sustained weight loss was observed after surgery in both groups, with reductions in BMI. MMP-2 and MMP-9 levels decreased significantly after one year of follow-up.

CONCLUSIONS

Bariatric surgery is an effective long-term intervention for weight loss and associated comorbidities, including T2DM. MMP-2 and MMP-9 proved to be effective markers of extracellular matrix remodeling, with significant reductions following surgery.

Targeting Matrix Metalloproteinases and Their Inhibitors in Melanoma

Malignant melanoma is one of the most important dermatological neoplasms. The high mortality rate associated with this skin disease is primarily due to the occurrence of metastases, while the diagnosis and treatment of melanoma in its early stages has a favorable prognosis. Early detection is crucial because the success of treatment is directly related to the depth of cancerous growth. The family of matrix metalloproteinases (MMPs) plays a critical role in the initiation and progression of melanoma. Prominent MMPs, including MMP-1, MMP-2, MMP-3, MMP-9, MMP-13, and MMP-14, have been shown to significantly contribute to the development of melanoma. The tumor microenvironment, particularly the extracellular matrix (ECM), has emerged as a critical factor in modulating cancer progression. This review focuses on the role of matrix metalloproteinases and their inhibitors in ECM degradation and the subsequent progression of melanoma, as well as their potential as therapeutic targets.

Special Issue: The Role of Extracellular Matrix Proteins in Pathogenesis

The extracellular matrix (ECM) serves as a complex network that regulates cellular behavior and maintains tissue architecture [...].

Molecular and metabolomic characterization of hiPSC-derived cardiac fibroblasts transitioning to myofibroblasts

Background

Mechanical stress and pathological signaling trigger the activation of fibroblasts to myofibroblasts, which impacts extracellular matrix composition, disrupts normal wound healing, and can generate deleterious fibrosis. Myocardial fibrosis independently promotes cardiac arrhythmias, sudden cardiac arrest, and contributes to the severity of heart failure. Fibrosis can also alter cell-to-cell communication and increase myocardial stiffness which eventually may lead to lusitropic and inotropic cardiac dysfunction. Human induced pluripotent stem cell derived cardiac fibroblasts (hiPSC-CFs) have the potential to enhance clinical relevance in precision disease modeling by facilitating the study of patient-specific phenotypes. However, it is unclear whether hiPSC-CFs can be activated to become myofibroblasts akin to primary cells, and the key signaling mechanisms in this process remain unidentified.

Objective

We aim to explore the notable changes in fibroblast phenotype upon passage-mediated activation of hiPSC-CFs with increased mitochondrial metabolism, like primary cardiac fibroblasts.

Methods

We activated the hiPSC-CFs with serial passaging from passage 0 to 3 (P0 to P3) and treatment of P0 with TGFβ1.

Results

Passage-mediated activation of hiPSC-CFs was associated with a gradual induction of genes to initiate the activation of these cells to myofibroblasts, including collagen, periostin, fibronectin, and collagen fiber processing enzymes with concomitant downregulation of cellular proliferation markers. Most importantly, canonical TGFβ1 and Hippo signaling component genes including TAZ were influenced by passaging hiPSC-CFs. Seahorse assay revealed that passaging and TGFβ1 treatment increased mitochondrial respiration, consistent with fibroblast activation requiring increased energy production, whereas treatment with the glutaminolysis inhibitor BPTES completely attenuated this process.

Conclusion

Our study highlights that the hiPSC-CF passaging enhanced fibroblast activation, activated fibrotic signaling pathways, and enhanced mitochondrial metabolism approximating what has been reported in primary cardiac fibroblasts. Thus, hiPSC-CFs may provide an accurate in vitro preclinical model for the cardiac fibrotic condition, which may facilitate the identification of putative anti-fibrotic therapies, including patient-specific approaches.

Matrix Metalloproteinases on Skin Photoaging

BACKGROUND

Skin aging is characterized by an imbalance between the generation and degradation of extracellular matrix molecules (ECM). Matrix metalloproteinases (MMPs) are the primary enzymes responsible for ECM breakdown. Intrinsic and extrinsic stimuli can induce different MMPs. However, there is limited literature especially on the summary of skin MMPs and potential inhibitors.

OBJECTIVE

We aim to focus on the upregulation of MMP expression or activity in skin cells following exposure to UV radiation. We also would like to offer valuable insights into potential clinical applications of MMP inhibitors for mitigating skin aging.

METHODS

This article presents the summary of prior research, which involved an extensive literature search across diverse academic databases including Web of Science and PubMed.

RESULTS

Our findings offer a comprehensive insight into the effects of MMPs on skin aging after UV irradiation, including their substrate preferences and distinct roles in this process. Additionally, a comprehensive list of natural plant and animal extracts, proteins, polypeptides, amino acids, as well as natural and synthetic compounds that serve as inhibitors for MMPs is compiled.

CONCLUSION

Skin aging is a complex process influenced by environmental factors and MMPs. Research focuses on UV-induced skin damage and the formation of Advanced Glycosylation End Products (AGEs), leading to wrinkles and impaired functionality. Inhibiting MMPs is crucial for maintaining youthful skin. Natural sources of MMP inhibitor substances, such as extracts from plants and animals, offer a safer approach to obtain inhibitors through dietary supplements. Studying isolated active ingredients can contribute to developing targeted MMP inhibitors.

Collagen and collagenases in mare's endometrium with endometrosis

Equine endometrosis is a degenerative and predominantly fibrotic condition resulting from progressive and irreversible multifactorial causes that influence the endometrium of mare. Tissue remodeling in the equine endometrium occurs as part of the pathogenesis of endometrosis, a process characterized by a shift in extracellular matrix (ECM) components. The relationship between matrix metalloproteinases and their specific inhibitors is crucial for the remodeling process. Collagen play a significant role in maintaining a healthy uterus and may promote fibrotic processes. The aim of this study was to quantify endometrial collagen deposition using picrosirius 25 red (PSR) staining, and to evaluate gene expression of collagen type 2 (COL-2) and 3 (COL-3), matrix metalloproteinases 1 (MMP-1) and 2 (MMP-2), their tissue inhibitor (TIMP-2), and tumor necrosis factor (TNF-α) in the endometrium of mares with different grades of fibrosis. The samples (n = 34) were classified into three categories based on the frequency and distribution of fibrosis-related changes in the endometrium: Category I (healthy endometrium, n = 12), Category II (moderate fibrosis, n = 12), and Category III (severe fibrosis, n = 10). Collagen quantification demonstrate a substantial proportional increase (P < 0.0001) in collagen deposition across Category I (11.72 ± 1.39 %), Category II (17.76 ± 1.29 %), and Category III (24.15 ± 1.87 %). In transcript evaluations, higher COL-2 expression was found in Category II than in mares classified as Category I or III. MMP-1 showed increased transcript expression in Category II compared to Category III endometrial samples. Higher expression of MMP-2 was detected in Category III than in Category I and II. TIMP-2 showed lower mRNA expression in Category III vs Category I and II. However, TNF-α gene expression was higher in Category II than in Categories I and III. This study demonstrates that endometrial evaluation using PSR can play an important role in routine analyses for the detection and objective quantification of collagen in endometrial tissues. Additionally, this study demonstrated through gene expression analysis that MMP-1 may be linked to physiological endometrial remodeling. In contrast, MMP-2 could be associated with fibrogenesis in the endometrium, which is regulated by the inhibitor TIMP-2. Furthermore, COL-2 and TNF-α could be considered as biological markers involved in the progression endometrosis in mares. As such, the results of this study may contribute to the development of future antifibrotic therapies that aim to delay or even reverse the pathological remodeling of the extracellular matrix in the uterus, in addition to optimizing the diagnosis and prognosis of endometrial fibrosis in mares.

Vascular fibrosis and extracellular matrix remodelling in post-COVID 19 conditions

Causal associations between viral infections and acute myocardial injury are not fully understood, with mechanisms potentially involving direct cardiovascular involvement or systemic inflammation. This review explores plausible mechanisms of vascular fibrosis in patients with post-COVID-19 syndrome, focusing on extracellular matrix remodelling. Despite global attention, significant mechanistic or translational breakthroughs in the management of post-viral syndromes remain limited. No effective pharmacological or non-pharmacological interventions are currently available for patients experiencing persistent symptoms following COVID-19 infection. The substantial expansion of scientific knowledge resulting from collaborative efforts by medical experts, scientists, and government organisations in undertaking COVID-19 research could inform treatment strategies for other post-viral syndromes and respiratory illnesses. There is a critical need for clinical trials to evaluate potential therapeutic candidates, providing evidence to guide treatment decisions for post-COVID-19 syndromes.

Inflammation and lipoperoxidation in mucopolysaccharidoses type II patients at diagnosis and post-hematopoietic stem cell transplantation

INTRODUCTION

Mucopolysaccharidosis type II (MPS II) is caused by deficiency of the enzyme iduronate-2-sulfatase; one possible therapy for MPS II is hematopoietic stem cell transplantation (HSCT). It is established that there is excessive production of reactive species in MPS II patients, which can trigger several processes, such as the inflammatory cascade.

OBJECTIVES

Our aim was to outline an inflammatory profile and lipoperoxidation of MPS II patients for a better understanding of disease and possible benefits that HSCT can bring in these processes.

MATERIALS AND METHODS

We investigate oxidative damage to lipids by 15-F2t-isoprostane urinary concentrations and plasma pro-and anti-inflammatory cytokine concentrations in MPS II patients at diagnosis, MPS II post-HSCT patients, and controls.

RESULTS

Interleukin (IL)-1β and IL-17a concentrations were significantly increased and a tendency toward increased IL-6 production in the diagnosis group was verified. We found significant decrease in IL-4 and increase in 15-F2t-isoprostane concentrations in the diagnosis group, while IL-1β, IL-6, IL-17a and 15-F2t-isoprostane concentrations were similar between control and post-HSCT groups.

CONCLUSIONS

Our study demonstrated that MPS II patients at diagnosis are in a pro-inflammatory state, bringing a novel result showing increased production of IL-17a, an osteoclastogenic cytokine, as well as demonstrating that these patients have oxidative damage to lipids. Furthermore, evidence suggests that HSCT can reduce inflammation and lipoperoxidation in MPS II patients.

Recoverability of zebrafish from decabromodiphenyl ether exposure: The persisted interference with extracellular matrix production and collagen synthesis and the enhancement of arrhythmias

As a widely used brominated flame retardant, the widespread presence of decabromodiphenyl ether (BDE-209) in the natural environment and the toxicity risks it poses are well established, but the recoverability of BDE-209-induced individual injuries remains unknown. Therefore, a 7-day depuration experiment following a 4-day exposure of zebrafish to BDE-209 was conducted to confirm the recoverability and its mode of action. Oxidative stress after depuration was significantly reduced compared with BDE-209 exposure as indicated by the decreased expression level of oxidative stress-related genes and the reduced MDA, Gpx, and GST in zebrafish, indicating a gradual recovery of antioxidant activity. However, BDE-209 inhibition of extracellular matrix (ECM) proteins worsened after depuration. Mechanistically, BDE-209 mediated ECM production and secretion by down-regulating integrin expression. Furthermore, BDE-209 inhibition of collagen synthesis worsened after depuration. Biochemical assays and histopathological observations revealed a same result in zebrafish. Mechanistically, lysine hydroxylation is inhibited thereby affecting collagen synthesis. Interestingly, zebrafish showed arrhythmia after depuration compared to BDE-209 exposure, and abnormal changes in ATPase levels indicated that disturbances in Ca2+ homeostasis contributed to arrhythmia. Collectively, BDE-209-induced interference with ECM production and collagen synthesis persisted after depuration, which will provide new insights for understanding the recovery patterns of individuals under BDE-209 stress.

Structure optimization and molecular dynamics studies of new tumor-selective s-triazines targeting DNA and MMP-10/13 for halting colorectal and secondary liver cancers

A series of triazole-tethered triazines bearing pharmacophoric features of DNA-targeting agents and non-hydroxamate MMPs inhibitors were synthesized and screened against HCT-116, Caco-2 cells, and normal colonocytes by MTT assay. 7a and 7g surpassed doxorubicin against HCT-116 cells regarding potency (IC50 = 0.87 and 1.41 nM) and safety (SI = 181.93 and 54.41). 7g was potent against liver cancer (HepG-2; IC50 = 65.08 nM), the main metastatic site of CRC with correlation to MMP-13 expression. Both derivatives induced DNA damage at 2.67 and 1.87 nM, disrupted HCT-116 cell cycle and triggered apoptosis by 33.17% compared to doxorubicin (DNA damage at 0.76 nM and 40.21% apoptosis induction). 7g surpassed NNGH against MMP-10 (IC50 = 0.205 μM) and MMP-13 (IC50 = 0.275 μM) and downregulated HCT-116 VEGF related to CRC progression by 38%. Docking and MDs simulated ligands-receptors binding modes and highlighted SAR. Their ADMET profiles, drug-likeness and possible off-targets were computationally predicted.

Protein biomarkers in assessing kidney quality before transplantation‑current status and future perspectives (Review)

To meet the demand for kidney transplants (KTx), organs are frequently retrieved not only from standard criteria donors (SCD; a donor who is aged <50 years and suffered brain death from any number of causes, such as traumatic injuries or a stroke) but also from expanded criteria donors (any donor aged >60 years or donors aged >50 years with two of the following: A history of high blood pressure, a creatinine serum level ≥1.5 mg/dl or death resulting from a stroke). This comes at the cost of a higher risk of primary non‑function (the permanent hyperkalemia, hyperuremia and fluid overload that result in the need for continuous dialysis after KTx), delayed graft function (the need for dialysis session at least once during the first week after KTx), earlier graft loss and urinary complications (vesico‑ureteral reflux, obstruction of the vesico‑ureteral anastomosis, urine leakage). At present, there are no commercially available diagnostic tools for assessing kidney quality prior to KTx. Currently available predictive models based on clinical data, such as the Kidney Donor Profile Index, are insufficient. One promising option is the application of perfusion solutions for protein biomarkers of kidney quality and predictors of short‑ and long‑term outcomes. However, to date, protein markers that can be detected with ELISA, western blotting and cytotoxic assays have not been identified to be a beneficial predictors of kidney quality. These include lactate dehydrogenases, glutathione S‑transferases, fatty acid binding proteins, extracellular histones, IL‑18, neutrophil gelatinase‑associated lipocalin, MMPs and kidney injury molecule‑1. However, novel methods, including liquid chromatography‑mass spectrometry (LC‑MS) and microarrays, allow the analysis of all renal proteins suspended/dissolved in the acellular preservation solution used for kidney storage before KTx (including hypothermic machine perfusion as one of kidney storage methods) e.g. Belzer University of Wisconsin. Recent proteomic studies utilizing LC‑MS have identified complement pathway elements (C3, C1QB, C4BPA, C1S, C1R and C1RL), desmoplakin, blood coagulation pathway elements and immunoglobulin heavy variable 2‑26 to be novel predictors of kidney quality before transplantation. This was because they were found to correlate with estimated glomerular filtration rate at 3 and 12 months after kidney transplantation. However, further proteomic studies focusing on distinct markers obtained from hypothermic and normothermic machine perfusion are needed to confirm their predictive value and to improve kidney storage methods. Therefore, the present literature review from PubMed, Scopus, Embase and Web of Science was performed with the aims of summarizing the current knowledge on the most frequently studied single protein biomarkers. In addition, novel analytical methods and insights into organ injury during preservation were documented, where future directions in assessing organ quality before kidney transplantation were also discussed.

Matrix metalloproteinases in kidney homeostasis and diseases: an update

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases with important roles in kidney homeostasis and pathology. While capable of collectively degrading each component of the extracellular matrix, MMPs also degrade nonmatrix substrates to regulate inflammation, epithelial plasticity, proliferation, apoptosis, and angiogenesis. More recently, intriguing mechanisms that directly alter podocyte biology have been described. There is now irrefutable evidence for MMP dysregulation in many types of kidney disease including acute kidney injury, diabetic and hypertensive nephropathy, polycystic kidney disease, and Alport syndrome. This updated review will detail the complex biology of MMPs in kidney disease.

Unveiling the molecular Hallmarks of Peyronie's disease: a comprehensive narrative review

Peyronie's disease, a fibroinflammatory disorder, detrimentally impacts the sexual well-being of men and their partners. The manifestation of fibrotic plaques within penile tissue, attributed to dysregulated fibrogenesis, is pathognomonic for this condition. The onset of fibrosis hinges on the perturbation of the equilibrium between matrix metalloproteinases (MMPs), crucial enzymes governing the extracellular matrix, and tissue inhibitors of MMPs (TIMPs). In the context of Peyronie's disease, there is an elevation in TIMP levels coupled with a decline in MMP levels, culminating in fibrogenesis. Despite the scant molecular insights into fibrotic pathologies, particularly in the context of Peyronie's disease, a comprehensive literature search spanning 1995 to 2023, utilizing PubMed Library, was conducted to elucidate these mechanisms. The findings underscore the involvement of growth factors such as FGF and PDGF, and cytokines like IL-1 and IL-6, alongside PAI-1, PTX-3, HIF, and IgG4 in the fibrotic cascade. Given the tissue-specific modulation of fibrosis, comprehending the molecular underpinnings of penile fibrosis becomes imperative for the innovation of novel and efficacious therapies targeting Peyronie's disease. This review stands as a valuable resource for researchers and clinicians engaged in investigating the molecular basis of fibrotic diseases, offering guidance for advancements in understanding Peyronie's disease.

MMP-9 expression in rat pup incisor teeth is not altered by maternal hypertension or maternal atenolol treatment during pregnancy and lactation

Hypertension alters tooth formation and Atenolol reduces the blood pressure of spontaneously hypertensive rats (SHR) during pregnancy and lactation, and as demonstrated before, increases the microhardness of the SHR offspring's teeth. MMP-9 is overexpressed in different tissues of hypertensive animals and treatment of hypertension substances can reverse this alteration. We hypothesize hypertension alters the expression of MMP-9 in dental structures of SHR offspring and that treating female SHR with atenolol prevents this alteration. This study aimed to evaluate the expression of matrix metalloproteinase (MMP-9) in incisor teeth (IT) in male offspring of SHR (30 days old) treated or untreated with Atenolol during pregnancy and lactation. MMP-9 expression was evaluated in ameloblasts (AM), enamel matrix (EM), odontoblasts (OD), and predentin (PD) of IT through immunohistochemical reactions (immunoperoxidase). Data were analyzed by Shapiro-Wilk and Kruskal-Wallis (p < 0.05), with Dunn post-test. Histological differences were not observed between IT tissues of SHR and normotensive Wistar rats. For the first time, our data showed that MMP-9 expression in specific dental structures is not altered in SHR. Atenolol treatment increased MMP-9 immunostaining in EM of Wistar rat, however, Atenolol did not alter MMP-9 in the IT tissues of SHR. Our results demonstrated that MMP-9 expression in dental tissues is not affected by hypertension or atenolol treatment in dental tissues. If confirmed in humans, the results obtained in this study will corroborate the suggestion that MMP-9 is not a viable therapeutic target for the treatment of dental alterations associated with maternal hypertension.

Latest advance anti-inflammatory hydrogel wound dressings and traditional Lignosus rhinoceros used for wound healing agents

Wound healing is a physiological process occurring after the onset of a skin lesion aiming to reconstruct the dermal barrier between the external environment and the body. Depending on the nature and duration of the healing process, wounds are classified as acute (e.g., trauma, surgical wounds) and chronic (e.g., diabetic ulcers) wounds. The latter, often affect millions of people globally, take months to heal or not heal non-healing chronic wounds, are typically susceptible to microbial infection, and are a major cause of morbidity. Wounds can be treated with a variety of non-surgical (topical formulations, wound dressings) and surgical (debridement, skin grafts/flaps) methods. Three-dimensional (3D)-(bio) printing and traditional wound dressings are two examples of modern experimental techniques. This review focuses on several types of anti-inflammatory wound dressings, especially focusing on hydrogels and traditional macro-fungi like L. rhinocerotis as agents that promote wound healing. In this study, we introduced novel anti-inflammatory hydrogel dressings and offered innovative methods for application and preparation to aid in the healing. Additionally, we summarize the key elements required for wound healing and discuss our analysis of potential future issues. These findings suggest that L. rhinocerotis and various anti-inflammatory hydrogels can be considered as conventional and alternative macro-fungi for the treatment of non-communicable diseases. We summarized the development of functional hydrogel dressings and traditional Lignosus rhinoceros used for wound healing agents in recent years, as well as the current situation and future trends, in light of their preparation mechanisms and functional effects.

Modeling collagen fibril degradation as a function of matrix microarchitecture

Collagenolytic degradation is a process fundamental to tissue remodeling. The microarchitecture of collagen fibril networks changes during development, aging, and disease. Such changes to microarchitecture are often accompanied by changes in matrix degradability. In a matrix, the pore size and fibril characteristics such as length, diameter, number, orientation, and curvature are the major variables that define the microarchitecture. In vitro, collagen matrices of the same concentration but different microarchitectures also vary in degradation rate. How do different microarchitectures affect matrix degradation? To answer this question, we developed a computational model of collagen degradation. We first developed a lattice model that describes collagen degradation at the scale of a single fibril. We then extended this model to investigate the role of microarchitecture using Brownian dynamics simulation of enzymes in a multi-fibril three dimensional matrix to predict its degradability. Our simulations predict that the distribution of enzymes around the fibrils is non-uniform and depends on the microarchitecture of the matrix. This non-uniformity in enzyme distribution can lead to different extents of degradability for matrices of different microarchitectures. Our simulations predict that for the same enzyme concentration and collagen concentration, a matrix with thicker fibrils degrades more than that with thinner fibrils. Our model predictions were tested using in vitro experiments with synthetic collagen gels of different microarchitectures. Experiments showed that indeed degradation of collagen depends on the matrix architecture and fibril thickness. In summary, our study shows that the microarchitecture of the collagen matrix is an important determinant of its degradability.

Effects of Acute Maximum-Intensity Exercise on Matrix Metalloproteinase-2, -9, and Tissue Inhibitor of Metalloproteinase-1 Levels in Adult Males with Type 1 Diabetes Mellitus Treated with Insulin Pumps

Background: Dysregulation of matrix metalloproteinases (MMPs) activity is considered one of the potential causes of vascular complications in diabetic patients. Since training volume may influence MMPs levels in varying ways, the aim of our study was to evaluate changes in MMPs levels following acute maximum-intensity exercise in male patients with type 1 diabetes mellitus (T1DM). Methods: This study included 24 male T1DM patients and 10 healthy controls. Aerobic capacity was evaluated with a treadmill test. Levels of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase-1 (TIMP-1) were measured both before the aerobic capacity test and 60 min after its completion utilizing enzyme-linked immunosorbent assay (ELISA) system kits. Results: Before the aerobic capacity test only, MMP-9 serum levels were significantly elevated in the T1DM group compared to the controls. Following maximum-intensity exercise, the levels of MMP-2, MMP-9, and TIMP-1 were significantly higher in T1DM patients than in the control group. Between-group comparisons revealed that maximum-intensity exercise induced a statistically significant increase in MMP-2 serum levels from baseline in T1DM patients compared to controls. Conclusions: Our findings suggest that high-intensity exercise in T1DM patients leads to dysregulation of MMPs, as manifested by a significant increase in MMP-2 levels. This dysregulation may play a role in the development of vascular complications in diabetic patients.

Role of Metalloproteinases in Adhesion to Radicular Dentin: A Literature Review

INTRODUCTION

Root dentin is a porous and complex dental surface that may have irregularities and deposits of organic material. To achieve an effective bond between restorative materials and root dentin, it is necessary that the restorative materials adhere intimately to the dentin surface. Metalloproteinases (MMPs) are a group of proteolytic enzymes that perform an important role in degrading the extracellular matrix and remodeling connective tissue. The aim of this research was to determine the scientific evidence available on the role played by MMPs in adhesion to root dentin and their putative inhibitors.

MATERIALS AND METHODS

Several techniques have been used to evaluate the presence of MMPs in the root dentin of human and bovine teeth, such as Western blot, immunohistochemistry, immunofluorescence, and zymography, the latter also being used together with the EnzCheck assay to evaluate the inhibitory effect of adhesion protocols on the activity of root MMPs in vitro.

RESULTS

When analyzing the databases, 236 articles were found, 12 of which met the selection criteria. The variables analyzed were articles that evaluated different MMP inhibitors in root dentin.

CONCLUSIONS

In the adhesion to radicular dentin, MMPs have a crucial role in the degradation of the extracellular matrix of dentin and the remodeling of the dentin surface because excessive MMP activity can be harmful to dental health, since excessive degradation of the extracellular matrix of dentin can weaken the tooth structure and decrease fracture resistance. Therefore, it is important to monitor MMP activity during root dentin bonding procedures.

Integrating UHPLC-Q-TOF-MS/MS, network pharmacology, bioinformatics and experimental validation to uncover the anti-cancer mechanisms of TiaoPi AnChang decoction in colorectal cancer

ETHNOPHARMACOLOGICAL RELEVANCE

The TiaoPi AnChang Decoction (TPACD), a Traditional Chinese Medicine (TCM) prescription based on Xiangsha Liujunzi Decoction, has demonstrated clinical efficacy as an adjuvant therapy for colorectal cancer (CRC) patients. However, its specific ingredients and potential mechanisms of action remain unclear.

AIM OF THE STUDY

To identify the primary active ingredients of TPACD, their molecular targets, and potential mechanisms underlying the efficacy of TPACD in CRC treatment.

MATERIALS AND METHODS

This study investigated the clinically validated TCM formula TPACD. In vitro and in vivo experiments were used to demonstrate TPACD's regulatory effects on various malignant phenotypes of tumors, providing basic research support for its anti-cancer activity. To understand its pharmacodynamic basis, we utilized ultra-high performance liquid chromatography-quadrupole-time-of-flight-mass spectrometry/mass spectrometry (UHPLC-Q-TOF-MS/MS) to analyze TPACD constituents present in the bloodstream. Network pharmacology and bioinformatics analyses were used to identify potential active components and their molecular targets for TPACD's therapeutic effects in CRC. Subsequent experiments further elucidated its pharmacological mechanism.

RESULTS

TPACD inhibits various malignant cellular processes, such as cell proliferation, apoptosis, migration, and invasion, and has shown potential anti-CRC activities both in vitro and in vivo. Following the identification of 109 constituents absorbed into the blood from TPACD, network pharmacology analysis predicted 42 potential anti-CRC targets. Clinical analyses highlighted three genes as prognostic key genes of TPACD's therapeutic action: C-X-C motif chemokine ligand 8 (CXCL8), fatty acid binding protein 4 (FABP4), and matrix metallopeptidase 3 (MMP3). Drug sensitivity analyses, molecular docking simulations and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) identified MMP3 as the most promising target for TPACD's anti-CRC action. Enzyme activity assays confirmed that TPACD inhibits MMP3 enzyme activity. Surface plasmon resonance (SPR) characterized the binding affinity between MMP3 and effective active components of TPACD, including luteolin, quercetin, kaempferol, and liensinine.

CONCLUSIONS

TPACD exhibits anti-CRC activity in vitro and in vivo, with MMP3 identified as a critical target. The active compounds, including luteolin, quercetin, kaempferol, and liensinine, absorbed into the bloodstream, contribute to TPACD's efficacy by targeting MMP3.

Active-Matrix Metalloproteinase-8, Myeloperoxidase in Relation With Periodontics, Preterm Birth

OBJECTIVE

To investigate serum, placental levels of active-matrix metalloproteinase-8 (aMMP-8), myeloperoxidase (MPO) in preterm-birth with/without pre-eclampsia and term counterparts in relation with clinical periodontal parameters.

METHODS

Clinical periodontal measurements were recorded. Serum and placenta samples were collected during 173 full-term (FT), pre-term (PT) or pre-term complicated by pre-eclampsia (PTPE) deliveries. aMMP-8 levels were measured by IFMA. MPO levels in the serum and placenta samples were determined by ELISA. Data were tested using non-parametric tests.

RESULTS

PTBE group exhibited higher full-mouth probing depth and clinical attachment loss values than the other two groups (p < 0.05). Percentages of sites with plaque and bleeding on probing were lower in the PTBE group than in the other groups (p < 0.05). Serum aMMP-8 and MPO concentrations were higher in PTPE group than in the other groups (p < 0.05). Placenta aMMP-8 level was higher in the control group than in the PTPE group (p < 0.05). There was no significant difference between the groups in the placenta MPO levels (p > 0.05).

CONCLUSIONS

Within the limits of this cross-sectional study, it may be suggested that serum aMMP-8 and MPO concentrations together with placenta aMMP-8 levels may be associated with and reflect adverse pregnancy outcomes. Clinical periodontal findings did not reveal significant associations with these proteolytic and oxidative biomarkers.

Gelatinolytic activity in dentin upon adhesive treatment

In this multi-parameter study, the effect of diverse factors related to adhesive application on the activation of host-derived gelatinases was investigated by gelatin zymography, in-situ zymography, fluorogenic DQ-gelatin assay and micro-tensile bond-strength (μTBS) testing. Gelatin zymography disclosed the presence of gelatinases in phosphoric acid-etched dentin powder, while two gold-standard adhesives generated no measurable MMP activation. In-situ zymography revealed that the interfacial gelatinolytic activity from specimens treated with the two adhesives appeared similar as that of the EDTA negative control, indicating no detectable gelatinases were activated upon adhesive treatment. In solution, MMP-2/9 activity significantly decreased upon interaction with both adhesives (two-way linear mixed effects model [LMEM]: p < 0.05); gelatinases were almost completely deactivated upon 1-week incubation at 37 °C (general linear model: p < 0.05); light-curing adhesives increased temperature up to 55 °C, which appeared sufficient to dramatically decrease MMP-2/9 activity (two-way ANOVA: p < 0.05). Finally, challenging adhesive-dentin interfaces with highly concentrated MMP-9 (at a much higher concentration than present in saliva) for 1 m did not significantly affect μTBS (two-way LMEM: p > 0.05). Taken together, the two adhesives did not activate but rather inhibited the release and activation of dentinal gelatinases.

Transcriptomic analysis of the 12 major human breast cell types reveals mechanisms of cell and tissue function

A fundamental question in biology, central to our understanding of cancer and other pathologies, is determining how different cell types coordinate to form and maintain tissues. Recognizing the distinct features and capabilities of the cells that compose these tissues is critical. Unfortunately, the complexity of tissues often hinders our ability to distinguish between neighboring cell types and, in turn, scrutinize their transcriptomes and generate reliable and tractable cell models for studying their inherently different biologies. We have recently introduced a novel method that permits the identification and purification of the 12 cell types that compose the human breast-nearly all of which could be reliably propagated in the laboratory. Here, we explore the nature of these cell types. We sequence mRNAs from each purified population and investigate transcriptional patterns that reveal their distinguishing features. We describe the differentially expressed genes and enriched biological pathways that capture the essence of each cell type, and we highlight transcripts that display intriguing expression patterns. These data, analytic tools, and transcriptional analyses form a rich resource whose exploration provides remarkable insights into the inner workings of the cell types composing the breast, thus furthering our understanding of the rules governing normal cell and tissue function.

A comparison of different cleaning approaches for blood contamination after curing universal adhesives on the dentine surface

OBJECTIVE

This study compared the effectiveness of various cleaning approaches, including spray rinsing, repreparing with diamond burs, and using phosphoric acid or sodium hypochlorite alone or with polyphenols (resveratrol or myricetin), in removing blood contamination from the dentine after adhesive light-curing.

METHODS

The contact angles of the treated surfaces were measured and scanning electron microscopy/ energy dispersive X-ray spectroscopy observation was performed. The bond strength and nanoleakage were assessed, and in situ zymography was performed before and after aging. Interactions between matrix metalloproteinase (MMP)-9 and polyphenols were evaluated using molecular dynamics and rhMMP-9 inhibition analyses. The destruction of sodium hypochlorite on collagen and the resistance of polyphenols-treated dentine collagen to enzymolysis were evaluated using the hydroxyproline (HYP) assay. The effect of polyphenols on dentine collagen crosslinking was assessed by Fourier Transform Infrared Spectroscopy.

RESULTS

The repreparation group had the lowest contact angle compared to the other groups. The spray rinsing group had the lowest bond strength and highest amounts of nanoleakage. Cleaning with phosphoric acid or sodium hypochlorite alone removed the blood contaminants and parts of the adhesive; moreover, applying polyphenols further improved the bond strength and decreased nanoleakage and MMP activity after aging. Both polyphenols inhibited rhMMP-9 activity and promoted collagen crosslinking. Sodium hypochlorite showed the maximum HYP release when used alone, which was decreased after adding polyphenols.

SIGNIFICANCE

Phosphoric acid or sodium hypochlorite cleaning can remove blood contamination from the dentine surface after adhesive curing, and the addition of polyphenols can improve the durability of dentine bonding.

Expression of Reversion-Inducing Cysteine-Rich Protein with Kazal Motifs (RECK) Gene and Its Regulation by miR200b in Ovarian Endometriosis

Endometriosis is a common chronic disorder characterized by the growth of endometrium-like tissue outside the uterine cavity. The disease is associated with chronic inflammation and pelvic pain and may have an impact on the patient's fertility. The causative factors and pathophysiology of the disease are still poorly recognized. The dysregulation of the immune system, aberrant tissue remodeling, and angiogenesis contribute to the disease progression. In endometriosis patients, the proteins regulating the breakdown and reorganization of the connective tissue, e.g., collagenases, and other proteases, as well as their inhibitors, show an incorrect pattern of expression. Here, we report that the expression of reversion-inducing cysteine-rich protein with Kazal motifs (RECK), one of the inhibitors of connective tissue proteases, is elevated in endometrioma cysts as compared to normal endometrium from unaffected women. We also demonstrate a reduced level of miR200b in endometriotic tissue that correlates with RECK mRNA levels. Furthermore, we employ the 12Z cell line, derived from a peritoneal endometriotic lesion, and the Ishikawa cell line, originating from endometrial adenocarcinoma to identify RECK as a direct target of miR200b. The described effect of miR200b on RECK, together with the aberrant expression of both genes in endometrioma, may help to understand the role played by the tissue remodeling system in the pathogenesis of endometriosis.

Floral Elegance Meets Medicinal Marvels: Traditional Uses, Phytochemistry, and Pharmacology of the Genus Lagerstroemia L

The genus Lagerstroemia L. (Lythraceae), known for its exquisite flowers and prolonged flowering period, is commonly employed in traditional medicinal systems across Asian countries, where it has always been consumed as tea or employed to address ailments such as diabetes, urinary disorders, coughs, fevers, inflammation, pain, and anesthesia. Its diverse uses may be attributed to its rich active ingredients. Currently, at least 364 biological compounds have been identified from Lagerstroemia extracts, encompassing various types such as terpenes, flavonoids, phenolic acids, alkaloids, and phenylpropanoids. Extensive in vitro and in vivo experiments have examined the pharmacological activities of different extracts, revealing their potential in various domains, including but not limited to antidiabetic, anti-obesity, antitumor, antimicrobial, antioxidant, anti-inflammatory, analgesic, and hepatoprotective effects. Additionally, 20 core components have been proven to be associated with antidiabetic and hypoglycemic effects of Lagerstroemia. Overall, Lagerstroemia exhibit substantial medicinal potential, and the alignment between its traditional applications and contemporary pharmacological findings present promising opportunities for further investigation, particularly in food and health products, drug development, herbal teas, and cosmetics. However, evidence-based pharmacological research has largely been confined to in vitro screening and animal model, lacking clinical trials and bioactive compound isolations. Consequently, future endeavors should adopt a more holistic approach.

miR126-mediated impaired vascular integrity in Rett syndrome

Rett syndrome (RTT) is a neurodevelopmental disorder that is caused by mutations in melty-CpG binding protein 2 (MeCP2). MeCP2 is a non-cell type-specific DNA binding protein, and its mutation influences not only neural cells but also non-neural cells in the brain, including vasculature associated with endothelial cells. Vascular integrity is crucial for maintaining brain homeostasis, and its alteration may be linked to the pathology of neurodegenerative disease, but a non-neurogenic effect, especially the relationship between vascular alternation and Rett syndrome pathogenesis, has not been shown. Here, we recapitulate a microvascular network using Rett syndrome patient-derived induced pluripotent stem (iPS) cells that carry MeCP2[R306C] mutation to investigate early developmental vascular impact. To expedite endothelial cell differentiation, doxycycline (DOX)-inducible ETV2 expression vectors were inserted into the AAVS1 locus of Rett syndrome patient-derived iPS cells and its isogenic control by CRISPR/Cas9. With these endothelial cells, we established a disease microvascular network (Rett-dMVNs) and observed higher permeability in the Rett-dMVNs compared to isogenic controls, indicating altered barrier function by MeCP2 mutation. Furthermore, we unveiled that hyperpermeability is involved in the upregulation of miR126-3p in Rett syndrome patient-derived endothelial cells by microRNA profiling and RNAseq, and rescue of miR126-3p level can recover their phenotype. We discover miR126-3p-mediated vascular impairment in Rett syndrome patients and suggest the potential application of these findings for translational medicine.

Escherichia coli induced matrix metalloproteinase-9 activity and type IV collagen degradation is regulated by progesterone in human maternal decidual

BACKGROUND

Escherichia coli (E. coli) is one of the main bacteria associated with preterm premature rupture of membranes by increasing pro-matrix metalloproteinase 9 (proMMP-9) and degradation of type IV collagen in human feto-maternal interface (HFMi). proMMP-9 is regulated by progesterone (P4) but it is unclear whether P4 inhibits proMMP in human maternal decidual (MDec). This study aimed to determine a role of P4 on proMMP-2 and - 9 and type IV collagen induced by E. coli infection in MDec.

METHODS

Nine HFMi were mounted in a Transwell system. MDec was stimulated with P4 or E. coli for 3-, 6-, or 24-hours. proMMP-2, -9 and type IV collagen were assessed.

RESULTS

Gelatin zymography revealed an increase in proMMP-9 after 3, 6, and 24 h of stimulating MDec with E. coli. Using immunofluorescence, it was confirmed the increase in the HFMi tissue and a reduction on the amount of type IV collagen leading to the separation of fetal amniochorion and MDEc. The degradative activity of proMMP-9 was reduced by 20% by coincubation with P4.

CONCLUSIONS

P4 modulates the activity of proMMP-9 induced by E. coli stimulation but it was unable to completely reverse the degradation of type IV collagen in human MDec tissue.

Update on the genetic profile of mitral valve development and prolapse

The purpose of this review is to present a comprehensive overview of the literature published up to February 2024 on the PubMed database regarding the development of mitral valve disease, with detailed reference to mitral valve prolapse, from embryology to a genetic profile. Out of the 3291 publications that deal with mitral valve embryology, 215 refer to mitral valve genetics and 83 were selected for further analysis. After reviewing these data, we advocate for the importance of a gene-based therapy that should be available soon, to prevent or treat non-invasively the valvular degeneration.

Angiogenesis unveiled: Insights into its role and mechanisms in cartilage injury

Osteoarthritis (OA) commonly results in compromised mobility and disability, thereby imposing a significant burden on healthcare systems. Cartilage injury is a prevalent pathological manifestation in OA and constitutes a central focus for the development of treatment strategies. Despite the considerable number of studies aimed at delaying this degenerative process, their outcomes remain unvalidated in preclinical settings. Recently, therapeutic strategies focused on angiogenesis have attracted the growing interest from researchers. Thus, we conducted a comprehensive literature review to elucidate the current progress in research and pinpoint research gaps in this domain. Additionally, it provides theoretical guidance for future research endeavors and the development of treatment strategies.

Unravelling the molecular tapestry of pterygium: insights into genes for diagnostic and therapeutic innovations

Pterygium, an ocular surface disorder, manifests as a wing-shaped extension from the corneoscleral limbus onto the cornea, impacting vision and causing inflammation. With a global prevalence of 12%, varying by region, the condition is linked to UV exposure, age, gender, and socioeconomic factors. This review focuses on key genes associated with pterygium, shedding light on potential therapeutic targets. Matrix metalloproteinases (MMPs), especially MMP2 and MMP9, contribute to ECM remodelling and angiogenesis in pterygium. Vascular endothelial growth factor (VEGF) plays a crucial role in angiogenesis and is elevated in pterygium tissues. B-cell lymphoma-2, S100 proteins, DNA repair genes (hOGG1, XRCC1), CYP monooxygenases, p53, and p16 are implicated in pterygium development. A protein-protein interaction network analysis highlighted 28 edges between the aforementioned proteins, except for VEGF, indicating a high level of interaction. Gene ontology, microRNA and pathway analyses revealed the involvement of processes such as base excision repair, IL-17 and p53 signalling, ECM disassembly, oxidative stress, hypoxia, metallopeptidase activity and others that are essential for pterygium development. In addition, miR-29, miR-125, miR-126, miR-143, miR-200, miR-429, and miR-451a microRNAs were predicted, which were shown to have a role in pterygium development and disease severity. Identification of these molecular mechanisms provides insights for potential diagnostic and therapeutic strategies for pterygium.