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Hyaluronidase and Gelatinase (MMP-2, MMP-9) Inhibitor Plants
Published in Megh R. Goyal, Durgesh Nandini Chauhan, Assessment of Medicinal Plants for Human Health, 2020
C. Donmez, G. D. Durbilmez, H. El-Seedi, U. Koca-Caliskan
Gelatinase is a proteolytic enzyme that catalyzes the breakdown of gelatin. Gelatinase includes MMPs that are found in human, vertebrate, and nonvertebrate.66 MMPs, belonging to the “Metzincins” superfamily, are calcium-dependent. These include MMP-2 (gelatinase-A) and MMP-9 (gelatinase-B). Their basic activity is to hydrolyze the gelatin to amino acid. Further, it reduces the extracellular matrix components (ECM) like elastin, fibronectin, and collagens (types IV, V, VII, and X) in helical domains.35 While activated MMP-2 may connect to integrin αvβ3 on the uppermost layer of angiogenic endothelial cells and spreading cancer cells, MMP-9 binds to type IV collagen α2 chains on the surface of various cell types especially in skin cancers.7,51 Moreover, angiogenesis and tumor cell invasion are supported via the localizations of MMPs to the cell surfaces. In malignant cancers, MMPs are activated and their levels are increased. Therefore, inhibition of these enzymes is required for treatments of many cancers.66 MMPs are involved in numerous biological and physiological processes, such as embryonic development, inflammatory response, tissue morphogenesis, wound repairing, bone remodeling, autoimmunity, and cell growth.45,50,52
Effects of TNF-α on Endothelial Control of Hemostasis
Published in Pia Glas-Greenwalt, Fibrinolysis in Disease Molecular and Hemovascular Aspects of Fibrinolysis, 2019
The TNF-α-induced secretion of u-PA by endothelial cells in vitro is vectorial.121 With endothelial cells cultured on porous filters it has been demonstrated that almost all u-PA is secreted to the basolateral side of the cell. On the other hand, the production of t-PA and PAI-1 occurs almost equally towards the luminal and the basolateral sides of the cells. The increased production of u-PA is accompanied by an increased degradation of extracellular matrix proteins.123 The pericellular action of u-PA is spatially controlled by a specific cellular receptor.27,83,133 Parallel with the induction of u-PA, TNF-α increases the expression of the matrix metalloproteinases stromelysin, type I collagenase, and gelatinase-B by endothelial cells.134 It is of interest to note that gelatinase activities are also secreted predominantly to the basolateral side of endothelial cells.135 This favors the idea that u-PA, probably together with plasmin and matrix metalloproteinases, has a function in proteolytic events regulating the interaction of the cell with its basal membrane. The simultaneous induction of u-PA and PAI-1 by TNF-α may therefore point to an additional function of PAI-1: to protect the extracellular matrix against excessive u-PA action.
Serratia
Published in Dongyou Liu, Handbook of Foodborne Diseases, 2018
Naheed S. Kanji, Umesh Narsinghani, Ritu A. Kumar
Serratia also has a unique ability to produce extracellular enzymes, specifically protease, DNase, lipase, and gelatinase2; thus, it can degrade chitin, a substance that is a main component of fungal cell walls.45 Such chitinolytic enzymes could have possible industrial and agricultural uses such as the introduction of these genes for chitin-degrading enzymes into crops and fermentative bacteria.46 Some Serratia species have the reproducible capability to break down casein via proteases that disrupt the peptide bonds (CO-NH) producing a clearing on milk agar plates. Hydrolysis of casein is not a common trait and thus is useful in the differentiation of Serratia from other strains of Enterobacteriaceae and Pseudomonadaceae.47 Similarly, gelatinase breaks down gelatin, an incomplete protein that lacks tryptophan. Gelatin hydrolysis transforms the protein to individual amino acids and causes it to liquefy in cold conditions under 25°C, when it would otherwise be solid.48 As a facultative anaerobe, Serratia uses fermentation as the means of gathering energy and produces enzymes such as superoxide dismutase, catalase, and peroxides that protect it from reactive oxygen species, allowing it to live in oxygenated environments.
Serum activity of matrix metalloproteinase-2 and -9 is increased in chronic post-stroke individuals: a cross-sectional exploratory study
Published in Topics in Stroke Rehabilitation, 2022
Luisa Fernanda García-Salazar, Jean Alex Matos Ribeiro, Jonathan Emanuel Cunha, Stela Marcia Mattiello, Thiago Luiz Russo
Matrix Metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that promote the degradation and synthesis of extracellular matrix (ECM) proteins. Among one of the categories of this type of enzymes are gelatinase matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9).1 In blood circulation, high concentrations of these gelatinases, are associated with an inflammatory process such as that observed after stroke.2,3 Activation of MMP-2 begins during hypoxia and participates in the disruption of the ECM proteins in the basal lamina and degrades the tight junction proteins.1,4 On the other hand, inducible MMP-9 enzymes, which are normally kept inactive, become active due to the action of free radicals and other enzymes, and induce the opening of the blood-brain barrier (BBB). This gelatinase degrades the neurovascular matrix, promoting neuroinflammation and vasogenic edema, including the activation of several other pro-inflammatory cytokines and chemokines such as interleukin (IL)-1 and tumor necrosis factor alpha (TNF-α).1,4
A small molecule II-6s inhibits Enterococcus faecalis biofilms
Published in Journal of Oral Microbiology, 2021
Xinyi Kuang, Jin Zhang, Xian Peng, Qian Xie, Jiyao Li, Xuedong Zhou, Youfu Luo, Xin Xu
Endodontic diseases are results from inflammation and destruction of pulp and periradicular tissues, primarily initiated by oral biofilms and associated with multiple risk factors [1]. Root canal disinfection, aiming to disrupt biofilms and kill bacteria inside, is critical for successful endodontic treatment [2]. Enterococcus faecalis is the main species commonly isolated from root canals with persistent endodontic infection or post-treatment endodontic diseases [3,4]. Certain virulence factors of E. faecalis, such as collagen-binding protein, gelatinase, enterococcal surface protein and aggregation substance mediate the adherence and biofilm formation on the dentin surface of the root canal system [4–6]. E. faecalis can invade into dentinal tubules, compete with other microorganisms, and survive in the root canals with poor nutrition [3].
Combatting resistant enterococcal infections: a pharmacotherapy review
Published in Expert Opinion on Pharmacotherapy, 2018
Nicholas J Mercuro, Susan L Davis, Marcus J Zervos, Erica S Herc
Many agents with activity against Gram-positive bacteria are obsolete against enterococci due to intrinsic mechanisms of resistance: efflux pumps deter lincosamide activity; high-level cephalosporin resistance occurs through production of penicillin-binding proteins (PBP) 4/5; poor cell wall permeability prevents aminoglycoside activity; and folate synthesis inhibitors are hindered as Enterococcus absorbs folic acid from its environment [6]. Even the heavily depended-on classes of penicillin, oxazolidinone, lipopeptide, and glycopeptide antibiotics are subject to bacterial resistance through acquisition of plasmids and movement of transposons (Figure 2) [6]. In addition to resistance, the production of bacterial toxins, enzymes, and biofilms contribute to the elusiveness of enterococci. E. faecalis express toxins such as cytolysin/hemolysin, which contribute to cell lysis and virulence, while gelatinase and serine protease enzymes degrade host tissues, regulate development of biofilms, and facilitate microbial invasion. Adhesins and collagen binding proteins in E. faecalis and E. faecium support biofilm formation featured in endovascular infections [7]. Together, these factors complicate management of enterococcal infections.