Implications of MMP-12 in the pathophysiology of ischaemic stroke

This article focuses on the emerging role of matrix metalloproteinase-12 (MMP-12) in ischaemic stroke (IS). MMP-12 expression in the brain increases dramatically in animal models of IS, and its suppression reduces brain damage and promotes neurological, sensorimotor and cognitive functional outcomes. Thus, MMP-12 could represent a potential target for the management of IS. This article provides an overview of MMP-12 upregulation in the brain following IS, its deleterious role in the post-stroke pathogenesis (blood-brain barrier disruption, inflammation, apoptosis and demyelination), possible molecular interactions and mechanistic insights, its involvement in post-ischaemic functional deficits and recovery as well as the limitations, perspectives, challenges and future directions for further research. Prior to testing any MMP-12-targeted therapy in patients with acute IS, additional research is needed to establish the effectiveness of MMP-12 suppression against IS in older animals and in animals with comorbidities. This article also examines the clinical implications of suppressing MMP-12 alone or in combination with MMP-9 for extending the currently limited tissue plasminogen activator therapy time window. Targeting of MMP-12 is expected to have a profound influence on the therapeutic management of IS in the future.

Batimastat Induces Cytotoxic and Cytostatic Effects in In Vitro Models of Hematological Tumors

The role of metalloproteinases (MMPs) in hematological malignancies, like acute myeloid leukemia (AML), myelodysplastic neoplasms (MDS), and multiple myeloma (MM), is well-documented, and these pathologies remain with poor outcomes despite treatment advancements. In this study, we investigated the effects of batimastat (BB-94), an MMP inhibitor (MMPi), in single-administration and daily administration schemes in AML, MDS, and MM cell lines. We used four hematologic neoplasia cell lines: the HL-60 and NB-4 cells as AML models, the F36-P cells as an MDS model, and the H929 cells as a model of MM. We also tested batimastat toxicity in a normal human lymphocyte cell line (IMC cells). BB-94 decreases cell viability and density in a dose-, time-, administration-scheme-, and cell-line-dependent manner, with the AML cells displaying higher responses. The efficacy in inducing apoptosis and cell cycle arrests is dependent on the cell line (higher effects in AML cells), especially with lower daily doses, which may mitigate treatment toxicity. Furthermore, BB-94 activated apoptosis via caspases and ERK1/2 pathways. These findings highlight batimastat's therapeutic potential in hematological malignancies, with daily dosing emerging as a strategy to minimize adverse effects.

Inhibition of MMP-2 and MMP-9 by Dietary Antioxidants in THP-1 Macrophages and Sera from Patients with Breast Cancer

Polyphenols, the main antioxidants of diet, have shown anti-inflammatory, antioxidant and anticarcinogenic activities. Here, we compared the effects of four polyphenolic compounds on ROS production and on the levels of matrix metalloproteinase (MMP)-2 and -9, which represent important pathogenetic factors of breast cancer. THP-1 differentiated macrophages were activated by LPS and simultaneously treated with different doses of a green tea extract (GTE), resveratrol (RSV), curcumin (CRC) and an olive fruit extract (oliplus). By using the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, we found that all of the tested compounds showed antioxidant activity in vitro. In addition, GTE, RSV and CRC were able to counteract ROS production induced by H2O2 in THP-1 cells. As assessed by a zymographic analysis of THP-1 supernatants and by an "in-gel zymography" of a pool of sera from patients with breast cancer, the antioxidant compounds used in this study inhibited both the activity and expression of MMP-2 and MMP-9 through different mechanisms related to their structures and to their ability to scavenge ROS. The results of this study suggest that the used antioxidants could be promising agents for the prevention and complementary treatment of breast cancer and other diseases in which MMPs play a pivotal role.

Discovery of matrix metalloproteinase inhibitors as anti-skin photoaging agents

Photodamage is the result of prolonged exposure of the skin to sunlight. This exposure causes an overexpression of matrix metalloproteinases (MMPs), leading to the abnormal degradation of collagen in the skin tissue and resulting in skin aging and damage. This review presents a detailed overview of MMPs as a potential target for addressing skin aging. Specifically, we elucidated the precise mechanisms by which MMP inhibitors exert their anti-photoaging effects. Furthermore, we comprehensively analyzed the current research progress on MMP inhibitors that demonstrate significant inhibitory activity against MMPs and anti-skin photoaging effects. The review also provides insights into the structure-activity relationships of these inhibitors. Our objective in conducting this review is to provide valuable practical information to researchers engaged in investigations on anti-skin photoaging.

Chemosensitization of non-small cell lung cancer to sorafenib via non-hydroxamate s-triazinedione-based MMP-9/10 inhibitors

Non-small cell lung cancer (NSCLC) continues to be a leading cause of cancer death. Its fatality is associated with angiogenesis and metastasis. While VEGFR inhibitors are expected to be the central pillar for halting lung cancer, several clinical reports declared their subpar activities as monotherapy. These results directed combination studies of VEGFR inhibitors, especially sorafenib (Nexavar®), with various chemotherapeutic agents. Matrix metalloproteinase (MMP) inhibitors are seldom utilized in such combinations despite the expected complementary therapeutic outcome. This could be attributed to the clinical unsuitability of MMP inhibitors from the hydroxamate family. Herein, we report new non-hydroxamate s-triazinedione-based inhibitors of MMP-9 (6b; IC50 = 0.112 μM), and MMP-10 (6e; IC50 = 0.076 μM) surpassing the hydroxamate inhibitor NNGH for chemosensitization of NSCLC to sorafenib. MMPs inhibition profiling of the hits revealed MMP-9 over -2 and MMP-10 over -13 selectivity. 6b and 6e were potent (IC50 = 0.139 and 0.136 µM), safe (SI up to 6.77) and superior to sorafenib (IC50 = 0.506 µM, SI = 6.27) against A549 cells. When combined with sorafenib, the studied MMP inhibitors enhanced its cytotoxic efficacy up to 26 folds as confirmed by CI and DRI values for 6b (CI = 0.160 and DRI = 22.175) and 6e (CI = 0.096 and DRI = 29.060). 6b and 6e exerted anti-invasive activities in A549 cells as single agents (22.66 and 39.67 %) and in sorafenib combinations (29.96 and 91.83 %) compared to untreated control. Both compounds downregulated VEGF in A549 cells by approximately 70 % when combined with sorafenib, highlighting enhanced anti-angiogenic activities. Collectively, combinations of 6b and 6e with sorafenib demonstrated synergistic NSCLC cytotoxicity with pronounced anti-invasive and anti-angiogenic activities introducing a promising start point for preclinical studies.

Data-Independent Acquisition Proteomics and N-Terminomics Methods Reveal Alterations in Mitochondrial Function and Metabolism in Ischemic-Reperfused Hearts

Myocardial ischemia-reperfusion (IR) (stunning) injury triggers changes in the proteome and degradome of the heart. Here, we utilize quantitative proteomics and comprehensive degradomics to investigate the molecular mechanisms of IR injury in isolated rat hearts. The control group underwent aerobic perfusion, while the IR injury group underwent 20 min of ischemia and 30 min of reperfusion to induce a stunning injury. As MMP-2 activation has been shown to contribute to myocardial injury, hearts also underwent IR injury with ARP-100, an MMP-2-preferring inhibitor, to dissect the contribution of MMP-2 to IR injury. Using data-independent acquisition (DIA) and mass spectroscopy, we quantified 4468 proteins in ventricular extracts, whereby 447 proteins showed significant alterations among the three groups. We then used subtiligase-mediated N-terminomic labeling to identify more than a hundred specific cleavage sites. Among these protease substrates, 15 were identified following IR injury. We identified alterations in numerous proteins involved in mitochondrial function and metabolism following IR injury. Our findings provide valuable insights into the biochemical mechanisms of myocardial IR injury, suggesting alterations in reactive oxygen/nitrogen species handling and generation, fatty acid metabolism, mitochondrial function and metabolism, and cardiomyocyte contraction.

MMP inhibition as a novel strategy for extracellular matrix preservation during whole liver decellularization

As the only reliable treatment option for end-stage liver diseases, conventional liver transplantation confronts major supply limitations. Accordingly, the decellularization of discarded livers to produce bioscaffolds that support recellularization with progenitor/stem cells has emerged as a promising translational medicine approach. The success of this approach will substantially be determined by the extent of extracellular matrix (ECM) preservation during the decellularization process. Here, we assumed that the matrix metalloproteinase (MMP) inhibition could reduce the ECM damage during the whole liver decellularization of an animal model using a perfusion-based system. We demonstrated that the application of doxycycline as an MMP inhibitor led to significantly higher preservation of collagen, glycosaminoglycans, and hepatic growth factor (HGF) contents, as well as mechanical and structural features, including tensile strength, fiber integrity, and porosity. Notably, produced bioscaffolds were biocompatible and efficiently supported cell viability and proliferation in vitro. We also indicated that produced bioscaffolds efficiently supported HepG2 cell function upon seeding onto liver ECM discs using albumin and urea assay. Additionally, MMP inhibitor pretreated decellularized livers were more durable in contact with collagenase digestion compared to control bioscaffolds in vitro. Using zymography, we confirmed the underlying mechanism that results in these promising effects is through the inhibition of MMP2 and MMP9. Overall, we demonstrated a novel method based on MMP inhibition to ameliorate the ECM structure and composition preservation during liver decellularization as a critical step in fabricating transplantable bioengineered livers.

Matrix Metalloproteinase-9 inhibitors as therapeutic drugs for traumatic brain injury

Traumatic brain injury (TBI) is one of the leading causes of morbidity and mortality among young adults and the elderly. In the United States, TBI is responsible for around 30 percent of all injuries brought on by injuries in general. Vasogenic cerebral edema due to blood-brain barrier (BBB) dysfunction and the associated elevation of intracranial pressure (ICP) are some of the major causes of secondary injuries following traumatic brain injury. Matrix metalloproteinase-9 (MMP-9) is a therapeutic target for being an enzyme that degrades the proteins that make up a part of the microvascular basal lamina as well as inter-endothelial tight junctions of the blood-brain barrier. MMP-9-mediated BBB dysfunctions and the compromise of the BBB is a major pathway that leads the development of vasogenic cerebral edema, elevation of ICP, poor cerebral perfusion and brain herniation following traumatic brain injury. That makes MMP-9 an effective therapeutic target and endogenous or exogenous MMP-9 inhibitors as therapeutic drugs for preventing secondary brain damage after traumatic brain injury. Although our understanding of the mechanisms that underlie the primary and secondary stages of damage following a TBI has significantly improved in recent years, such information has not yet resulted in the successful development of novel pharmacological treatment options for traumatic brain injury. Recent pre-clinical and/or clinical studies have demonstrated that there are several compounds with specific or non-specific MMP-9 inhibitory properties either directly binding and inhibiting MMP-9 or by indirectly inhibiting MMP-9, with potential as therapeutic agents for traumatic brain injury. This article reviews the efficacy of several such medications and potential agents that include endogenous and exogeneous compounds that are at various levels of research and development. MMP-9-based therapeutic drug development has enormous potential in the pharmacological treatment of cerebral edema and/or neuronal injury resulting from traumatic brain injury.

Effects of Kojic Acid-mediated Sonodynamic Therapy as a Matrix Metalloprotease-9 Inhibitor against Oral Squamous Cell Carcinoma: A Bioinformatics Screening and In Vitro Analysis

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a type of cancer that is responsible for a significant amount of morbidity and mortality worldwide. Researchers are searching for promising therapeutic methods to manage this cancer. In this study, an in silico approach was used to evaluate the activity of sonodynamic therapy (SDT) based on the use of Kojic acid as a sonosensitizer to inhibit matrix metalloprotease-9 (MMP-9) in OSCC.

MATERIALS AND METHODS

The three-dimensional structure of MMP-9 was predicted and validated by computational approaches. The possible functional role of MMP-9 was determined in terms of Gene Ontology (GO) enrichment analysis. In silico, molecular docking was then performed to evaluate the binding energies of Kojic acid with MMP-9, and ADME parameters and toxicity risks were predicted. The pharmacokinetics and drug-likeness properties of Kojic acid were assessed. Moreover, after the determination of the cytotoxicity effect of Kojic acid-mediated SDT, the change of mmp-9 gene expression was assessed on OSCC cells.

RESULTS

The results of the study showed that Kojic acid could efficiently interact with MMP-9 protein with a strong binding affinity. Kojic acid obeyed Lipinski's rule of five without violation and exhibited drug-likeness. The cytotoxic effects of Kojic acid and ultrasound waves on the OSCC cells were dose-dependent, and the lowest expression level of the mmp-9 gene was observed in SDT.

CONCLUSIONS

Overall, Kojic acid-mediated SDT as an MMP-9 inhibitor can be a promising adjuvant treatment for OSCC. The study highlights the potential of In silico approaches to evaluate therapeutic methods for cancer treatment.

Generation of Protease Inhibitory Antibodies by Functional In Vivo Selection

Targeting dysregulated protease expression and/or abnormal substrate proteolysis, highly selective inhibition of pathogenic proteases by monoclonal antibodies (mAbs) presents an attractive therapeutic approach for the treatment of diseases including cancer. Herein, we report a functional selection method for protease inhibitory mAbs by periplasmic co-expression of three recombinant proteins-a protease of interest, an antibody Fab library, and a modified β-lactamase TEM-1. We validate this approach by isolation of highly selective and potent mAbs inhibiting human matrix metalloproteinase 9 (MMP9).

A fragment-based exploration of diverse MMP-9 inhibitors through classification-dependent structural assessment

Matrix metalloproteinases (MMPs) are belonging to the Zn2+-dependent metalloenzymes. These can degenerate the extracellular matrix (ECM) that is entailed with various biological processes. Among the MMP family members, MMP-9 is associated with several pathophysiological circumstances. Apart from wound healing, remodeling of bone, inflammatory mechanisms, and rheumatoid arthritis, MMP-9 has also significant roles in tumor invasion and metastasis. Therefore, MMP-9 has been in the spotlight of anticancer drug discovery programs for more than a decade. In this present study, classification-based QSAR techniques along with fragment-based data mining have been carried out on divergent MMP-9 inhibitors to point out the important structural attributes. This current study may be able to elucidate the importance of several pivotal molecular fragments such as sulfonamide, hydroxamate, i-butyl, and ethoxy functions for imparting potential MMP-9 inhibition. These observations are in correlation with the ligand-bound co-crystal structures of MMP-9. Therefore, these findings are beneficial for the design and discovery of effective MMP-9 inhibitors in the future.

Exploring natural anthraquinones as potential MMP2 inhibitors: A computational study

OBJECTIVE

Matrix metalloproteinase-2 (MMP2) plays a significant role in cleaving extracellular matrix components, leading to many cancer cells' progression and invasion behavior. Therefore, MMP2 inhibition may hold promise for cancer treatment. Anthraquinones have shown antineoplastic effects, some of which have been used in clinical practice as anticancer drugs. This study used a computational drug discovery approach to assess the possible inhibitory effects of selected anthraquinones on MMP2. The results were then compared with that of Captopril, which was considered a standard drug.

METHODS

This study used the AutoDock 4.0 tool to evaluate the binding affinity of 21 anthraquinones to the MMP2 catalytic domain. The most favorable scores based on the Gibbs free binding energy scores were given to the highest-ranked ligands. The Discovery Studio Visualizer tool illustrated interactions between MMP2 residues and top-ranked anthraquinones.

RESULTS

A total of 12 anthraquinones were identified with ΔGbinding scores less than - 10 kcal/mol. Pulmatin (Chrysophanol-8-glucoside) was the most potent MMP2 inhibitor, with a ΔGbinding score of - 12.91 kcal/mol. This anthraquinone was able to restrict MMP2 activity within a picomolar range.

CONCLUSION

MMP2 inhibition by anthraquinones, notably Pulmatin, may be a useful therapeutic approach for cancer treatment.

Matrix Metalloproteinases in Oral Cancer Pathogenesis and their Use in Therapy

Matrix metalloproteinases (MMPs) are proteolytic enzymes that aid in extracellular matrix (ECM) remodeling. MMPs destroy the extracellular matrix, causing tumor growth and metastasis. MMPs are involved in the spread and metastasis of oral cancer. High levels of MMPs and oral squamous cell carcinoma have been linked to cancer prognosis. Modern medicine aims to prevent the illness from spreading through early intervention and examining changes in MMP genes. MMP gene polymorphism has recently been identified as one of the factors predicting susceptibility or risk in the development of oral carcinoma. This review aims to provide insight into the function of MMP subtypes involved in cancer. The genetic polymorphism in MMP genes and its predictive value in risk evaluation have been elaborated. Novel personalized therapeutic approaches for oral cancer, like the use of MMP inhibitors, nanoparticle-mediated targeting of MMP, or gene silencing by microRNA, can be designed.

Effect of MMP Inhibitors on the Bond Strength of Fibre Posts After Ageing

AIM

This in vitro study aimed to evaluate the effect of matrix metalloproteinase (MMP) inhibitors on the bond strength of resin-cemented fibre posts to radicular dentin under an aged-loaded condition.

MATERIALS AND METHODS

Radicular dentin was prepared and irrigated by MMP inhibitor solution after root canal obturation in 60 extracted single-rooted teeth based on 6 groups: (1) 2% chlorhexidine (CHX) + loaded; (2) CHX + unloaded; (3) 0.5% benzalkonium chloride (BAC) + loaded; (4) BAC + unloaded; (5) 17% ethylenediaminetetraacetic acid (EDTA) + loaded; and (6) EDTA + unloaded. After final rinsing, all specimens were sliced cross-sectionally and kept in a water bath for 12 months of ageing. Groups 1, 3, and 5 were subjected to cyclic loading. Push-out tests were conducted using a universal testing machine, and failure mode was examined. The data were analysed using 3-way analysis of variance and post hoc tests at α = 0.05.

RESULTS

BAC + unloaded demonstrated the highest mean bond strength (3.12 ± 0.18 MPa; P < .001), while the BAC + loaded and CHX + loaded groups showed a significantly lower push-out bond strength than their unloaded counterparts. Mixed adhesive-cohesive failure was the most common failure mode observed.

CONCLUSIONS

Without cycling loading, BAC was superior to CHX and EDTA in preserving the bond strength of resin-cemented fibre posts after 12 months of ageing. Loading significantly weakened the effectiveness of BAC and CHX in preserving the bond strength.

Enzyme-Responsive Nanoparticles for the Targeted Delivery of an MMP Inhibitor to Acute Myocardial Infarction

Herein, we have developed a drug-loaded matrix metalloproteinase (MMP)-responsive micellar nanoparticle (NP) intended for minimally invasive intravenous injection during the acute phase of myocardial infarction (MI) and prolonged retention in the heart for small-molecule drug delivery. Peptide-polymer amphiphiles (PPAs) bearing a small-molecule MMP inhibitor (MMPi), PD166793, were synthesized via ring-opening metathesis polymerization (ROMP) and formulated into spherical micelles by transitioning to aqueous solution. The resulting micellar NPs underwent MMP-induced aggregation, demonstrating enzyme responsiveness. Using a rat MI model, we observed that these NPs were capable of successfully extravasating into the infarcted region of the heart where they were retained due to the active, enzyme-mediated targeting, remaining detectable after 1 week post administration without increasing macrophage recruitment. Furthermore, in vitro studies show that these NPs demonstrated successful drug release following MMP treatment and maintained drug bioactivity as evidenced by comparable MMP inhibition to free MMPi. This work establishes a targeted NP platform for delivering small-molecule therapeutics to the heart after MI, opening possibilities for myocardial infarction treatment.

Structure-Based Optimization and Biological Evaluation of Potent and Selective MMP-7 Inhibitors for Kidney Fibrosis

Matrix metalloproteinase-7 (MMP-7) has been shown to play important roles in pathophysiological processes involved in the development/progression of diseases such as cancer and fibrosis. We discovered selective MMP-7 inhibitors composed of arylsulfonamide, carboxylate, and short peptides by a molecular hybridization approach. These compounds interacted with MMP-7 via multiple hydrogen bonds in the cocrystal structures. To obtain compounds for in vivo evaluation, we attempted structural optimization, particularly targeting Tyr167 at the S3 subsite through structure-based drug design, and identified compound 15 as showing improved MMP-7 potency and MMP subtype selectivity. A novel π-π stacking interaction with Tyr167 was achieved when 4-pyridylalanine was introduced as the P3 residue. Compound 15 suppressed the progression of kidney fibrosis in a dose-dependent manner in a mouse model of unilateral ureteral obstruction. Thus, we demonstrated, for the first time, that potent and selective MMP-7 inhibitors could prevent the progression of kidney fibrosis.

Type I collagen proteolysis by matrix metalloproteinase-2 contributes to focal adhesion kinase activation and vascular smooth muscle cell proliferation in the aorta in early hypertension

INTRODUCTION

Increased matrix metalloproteinase (MMP)-2 activity contributes to increase vascular smooth muscle cell (VSMC) proliferation in the aorta in early hypertension by cleaving many proteins of the extracellular matrix. Cleaved products from type I collagen may activate focal adhesion kinases (FAK) that trigger migration and proliferation signals in VSMC. We therefore hypothesized that increased activity of MMP-2 proteolyzes type I collagen in aortas of hypertensive rats, and thereby, induces FAK activation, thus leading to increased VSMC proliferation and hypertrophic remodeling in early hypertension.

METHODS

Male Sprague-Dawley rats were submitted to renovascular hypertension by the two kidney-one clip (2K1C) model and treated with doxycycline (30 mg/kg/day) by gavage from the third to seventh-day post-surgery. Controls were submitted to sham surgery. Systolic blood pressure (SBP) was measured daily by tail-cuff plethysmography and the aortas were processed for zymography and Western blot for MMP-2, pFAK/FAK, integrins and type I collagen. Mass spectrometry, morphological analysis and Ki67 immunofluorescence were also done to identify collagen changes and VSMC proliferation. A7r5 cells were stimulated with collagen and treated with the MMP inhibitors (doxycycline or ARP-100), and with the FAK inhibitor PND1186 for 24 h. Cells were lysed and evaluated by Western blot for pFAK/FAK.

RESULTS

2K1C rats developed elevated SBP in the first week as well as increased expression and activity of MMP-2 in the aorta (p < 0.05 vs. Sham). Treatment with doxycycline reduced both MMP activity and type I collagen proteolysis in aortas of 2K1C rats (p < 0.05). Increased pFAK/FAK and increased VSMC proliferation (p < 0.05 vs. Sham groups) were also seen in the aortas of 2K1C and doxycycline decreased both parameters (p < 0.05). Higher proliferation of VSMC contributed to hypertrophic remodeling as seen by increased media/lumen ratio and cross sectional area (p < 0.05 vs Sham groups). In cell culture, MMP-2 cleaves collagen, an effect reversed by MMP inhibitors (p < 0.05). Increased levels of pFAK/FAK were observed when collagen was added in the culture medium (p < 0.05 vs control) and MMP and FAK inhibitors reduced this effect.

CONCLUSIONS

Increase in MMP-2 activity proteolyzes type I collagen in the aortas of 2K1C rats and contributes to activate FAK and induces VSMC proliferation during the initial phase of hypertension.

An updated patent review of matrix metalloproteinase (MMP) inhibitors (2021-present)

INTRODUCTION

Matrix metalloproteinases (MMPs) are strongly interlinked with the progression and mechanisms of several life-threatening diseases including cancer. Thus, novel MMP inhibitors (MMPIs) as promising drug candidates can be effective in combating these diseases. However, no MMPIs are marketed to date due to poor pharmacokinetics and lower selectivity. Therefore, this review was performed to study the newer MMPIs patented after the COVID-19 period for an updated perspective on MMPIs.

AREAS COVERED

This review highlights patents related to MMPIs, and their therapeutic implications published between January 2021 and August 2023 available in the Google Patents, Patentscope, and Espacenet databases.

EXPERT OPINION

Despite various MMP-related patents disclosed up to 2020, newer patent applications in the post-COVID-19 period decreased a lot. Besides major MMPs, other isoforms (i.e. MMP-3 and MMP-7) have gained attention recently for drug development. This may open up newer dimensions targeting these MMPs for therapeutic advancements. The isoform selectivity and bioavailability are major concerns for effective MMPI development. Thus, adopting theoretical approaches and experimental methodologies can unveil the development of novel MMPIs with improved pharmacokinetic profiles. Nevertheless, the involvement of MMPs in cancer, and the mechanisms of such MMPs in other diseases should be extensively studied for novel MMPI development.

Assessing structural insights into in-house arylsulfonyl L-(+) glutamine MMP-2 inhibitors as promising anticancer agents through structure-based computational modelling approaches

MMP-2 is potentially contributing to several cancer progressions including leukaemias. Therefore, considering MMP-2 as a promising target, novel anticancer compounds may be designed. Here, 32 in-house arylsulfonyl L-(+) glutamines were subjected to various structure-based computational modelling approaches to recognize crucial structural attributes along with the spatial orientation for higher MMP-2 inhibition. Again, the docking-based 2D-QSAR study revealed that the Coulomb energy conferred by Tyr142 and total interaction energy conferred by Ala84 was crucial for MMP-2 inhibition. Importantly, the docking-dependent CoMFA and CoMSIA study revealed the importance of favourable steric, electrostatic, and hydrophobic substituents at the terminal phenyl ring. The MD simulation study revealed a lower fluctuation in the RMSD, RMSF, and Rg values indicating stable binding interactions of MMP-2 and these molecules. Moreover, the residual hydrogen bond and their interaction analysis disclosed crucial amino acid residues responsible for forming potential hydrogen bonding for higher MMP-2 inhibition. The results can effectively aid in the design and discovery of promising small-molecule drug-like MMP-2 inhibitors with greater anticancer potential in the future.

Novel Matrix Metalloproteinase-9 (MMP-9) Inhibitors in Cancer Treatment

Matrix metalloproteinases (MMPs) belong to a family of zinc-dependent proteolytic metalloenzymes. MMP-9, a member of the gelatinase B family, is characterized as one of the most intricate MMPs. The crucial involvement of MMP-9 in extracellular matrix (ECM) remodeling underscores its significant correlation with each stage of cancer pathogenesis and progression. The design and synthesis of MMP-9 inhibitors is a potentially attractive research area. Unfortunately, to date, there is no effective MMP-9 inhibitor that passes the clinical trials and is approved by the FDA. This review primarily focuses on exploring the diverse strategies employed in the design and advancement of MMP-9 inhibitors, along with their anticancer effects and selectivity. To illuminate the essential structural characteristics necessary for the future design of novel MMP-9 inhibitors, the current narrative review highlights several recently discovered MMP-9 inhibitors exhibiting notable selectivity and potency.

Computational design of matrix metalloprotenaise-9 (MMP-9) resistant to auto-cleavage

Matrix metalloproteinase-9 (MMP-9) is an endopeptidase that remodels the extracellular matrix. MMP-9 has been implicated in several diseases including neurodegeneration, arthritis, cardiovascular diseases, fibrosis and several types of cancer, resulting in a high demand for MMP-9 inhibitors for therapeutic purposes. For such drug design efforts, large amounts of MMP-9 are required. Yet, the catalytic domain of MMP-9 (MMP-9Cat) is an intrinsically unstable enzyme that tends to auto-cleave within minutes, making it difficult to use in drug design experiments and other biophysical studies. We set our goal to design MMP-9Cat variant that is active but stable to auto-cleavage. For this purpose, we first identified potential auto-cleavage sites on MMP-9Cat using mass spectroscopy and then eliminated the auto-cleavage site by predicting mutations that minimize auto-cleavage potential without reducing enzyme stability. Four computationally designed MMP-9Cat variants were experimentally constructed and evaluated for auto-cleavage and enzyme activity. Our best variant, Des2, with 2 mutations, was as active as the wild-type enzyme but did not exhibit auto-cleavage after 7 days of incubation at 37°C. This MMP-9Cat variant, with an identical with MMP-9Cat WT active site, is an ideal candidate for drug design experiments targeting MMP-9 and enzyme crystallization experiments. The developed strategy for MMP-9CAT stabilization could be applied to redesign other proteases to improve their stability for various biotechnological applications.

Matrix metalloproteinase-2 proteolyzes mitofusin-2 and impairs mitochondrial function during myocardial ischemia-reperfusion injury

During myocardial ischemia and reperfusion (IR) injury matrix metalloproteinase-2 (MMP-2) is rapidly activated in response to oxidative stress. MMP-2 is a multifunctional protease that cleaves both extracellular and intracellular proteins. Oxidative stress also impairs mitochondrial function which is regulated by different proteins, including mitofusin-2 (Mfn-2), which is lost in IR injury. Oxidative stress and mitochondrial dysfunction trigger the NLRP3 inflammasome and the innate immune response which invokes the de novo expression of an N-terminal truncated isoform of MMP-2 (NTT-MMP-2) at or near mitochondria. We hypothesized that MMP-2 proteolyzes Mfn-2 during myocardial IR injury, impairing mitochondrial function and enhancing the inflammasome response. Isolated hearts from mice subjected to IR injury (30 min ischemia/40 min reperfusion) showed a significant reduction in left ventricular developed pressure (LVDP) compared to aerobically perfused hearts. IR injury increased MMP-2 activity as observed by gelatin zymography and increased degradation of troponin I, an intracellular MMP-2 target. MMP-2 preferring inhibitors, ARP-100 or ONO-4817, improved post-ischemic recovery of LVDP compared to vehicle perfused IR hearts. In muscle fibers isolated from IR hearts the rates of mitochondrial oxygen consumption and ATP production were impaired compared to those from aerobic hearts, whereas ARP-100 or ONO-4817 attenuated these reductions. IR hearts showed higher levels of NLRP3, cleaved caspase-1 and interleukin-1β in the cytosolic fraction, while the mitochondria-enriched fraction showed reduced levels of Mfn-2, compared to aerobic hearts. ARP-100 or ONO-4817 attenuated these changes. Co-immunoprecipitation showed that MMP-2 is associated with Mfn-2 in aerobic and IR hearts. ARP-100 or ONO-4817 also reduced infarct size and cell death in hearts subjected to 45 min ischemia/120 min reperfusion. Following myocardial IR injury, impaired contractile function and mitochondrial respiration and elevated inflammasome response could be attributed, at least in part, to MMP-2 activation, which targets and cleaves mitochondrial Mfn-2. Inhibition of MMP-2 activity protects against cardiac contractile dysfunction in IR injury in part by preserving Mfn-2 and suppressing inflammation.

Designed Loop Extension Followed by Combinatorial Screening Confers High Specificity to a Broad Matrix MetalloproteinaseInhibitor

Matrix metalloproteinases (MMPs) are key drivers of various diseases, including cancer. Development of probes and drugs capable of selectively inhibiting the individual members of the large MMP family remains a persistent challenge. The inhibitory N-terminal domain of tissue inhibitor of metalloproteinases-2 (N-TIMP2), a natural broad MMP inhibitor, can provide a scaffold for protein engineering to create more selective MMP inhibitors. Here, we pursued a unique approach harnessing both computational design and combinatorial screening to confer high binding specificity toward a target MMP in preference to an anti-target MMP. We designed a loop extension of N-TIMP2 to allow new interactions with the non-conserved MMP surface and generated an efficient focused library for yeast surface display, which was then screened for high binding to the target MMP-14 and low binding to anti-target MMP-3. Deep sequencing analysis identified the most promising variants, which were expressed, purified, and tested for selectivity of inhibition. Our best N-TIMP2 variant exhibited 29 pM binding affinity to MMP-14 and 2.4 µM affinity to MMP-3, revealing 7500-fold greater specificity than WT N-TIMP2. High-confidence structural models were obtained by including NGS data in the AlphaFold multiple sequence alignment. The modeling together with experimental mutagenesis validated our design predictions, demonstrating that the loop extension packs tightly against non-conserved residues on MMP-14 and clashes with MMP-3. This study demonstrates how introduction of loop extensions in a manner guided by target protein conservation data and loop design can offer an attractive strategy to achieve specificity in design of protein ligands.

Metalloproteases in Pain Generation and Persistence: A Possible Target?

Matrix metalloproteinases (MMPs) are a large family of zinc-dependent proteolytic enzymes associated with extracellular matrix protein turnover and tissue degradation. They participate to many different physiological reactions but are also hyperactivated in several diseases. Various literature studies have documented that MMPs play a role in the modulation of neuropathic and nociceptive pain. The heterogeneity of clinical and pre-clinical data is an important issue in this experimental context. Despite the presence of a good number of studies on MMP inhibitors, these drugs showed scarce efficacy and relevant side effects. In the present manuscript, we reviewed studies in the literature that define a possible role of MMPs in pain and the effects of their modulation.

MT1-MMP Expression Levels and Catalytic Functions Dictate LDL Receptor-Related Protein-1 Ligand Internalization Capacity in U87 Glioblastoma Cells

Modulations in cell surface receptor ectodomain proteolytic shedding impact on receptor function and cancer biomarker expression. As such, heavily pursued therapeutic avenues have exploited LDL receptor-related protein-1 (LRP-1)-mediated capacity in internalizing Angiopep-2 (An2), a brain-penetrating peptide that allows An2-drug conjugates to cross the blood-brain tumor barrier (BBTB). Given that LRP-1 is proteolytically shed from the cell surface through matrix metalloproteinase (MMP) activity, the balance between MMP expression/function and LRP-1-mediated An2 internalization is unknown. In this study, we found that membrane type-1 (MT1)-MMP expression increased from grade 1 to 4 brain tumors, while that of LRP-1 decreased inversely. MMP pharmacological inhibitors such as Ilomastat, Doxycycline and Actinonin increased in vitro An2 internalization by up to 2.5 fold within a human grade IV-derived U87 glioblastoma cell model. Transient siRNA-mediated MT1-MMP gene silencing resulted in increased basal An2 cell surface binding and intracellular uptake, while recombinant MT1-MMP overexpression reduced both cell surface LRP-1 expression as well as An2 internalization. The addition of Ilomastat to cells overexpressing recombinant MT1-MMP restored LRP-1 expression at the cell surface and An2 uptake to levels comparable to those observed in control cells. Collectively, our data suggest that MT1-MMP expression status dictates An2-mediated internalization processes in part by regulating cell surface LRP-1 functions. Such evidence prompts preclinical evaluations of combined MMP inhibitors/An2-drug conjugate administration to potentially increase the treatment of high-MT1-MMP-expressing brain tumors.