Matrix Metalloproteinase-9 Activity Research Articles

Blood-brain barrier dysfunction and decreased transcription of tight junction proteins in epileptic dogs.

Epilepsy in dogs and humans is associated with blood-brain barrier (BBB) dysfunction (BBBD), which may involve dysfunction of tight junction (TJ) proteins, matrix metalloproteases, and astrocytes. Imaging techniques to assess BBB integrity, to identify potential treatment strategies, have not yet been evaluated in veterinary medicine. Some dogs with idiopathic epilepsy (IE) will exhibit BBBD. Identifying BBBD may improve antiepileptic treatment in the future. Twenty-seven dogs with IE and 10 healthy controls. Retrospective, prospective cohort study. Blood-brain barrier permeability (BBBP) scores were calculated for the whole brain and piriform lobe of all dogs by using dynamic contrast enhancement (DCE) magnetic resonance imaging (MRI) and subtraction enhancement analysis (SEA). Matrix metalloproteinase-9 (MMP9) activity in serum and cerebrospinal fluid (CSF) was measured and its expression in the piriform lobe was examined using immunofluorescent staining. Gene expression of TJ proteins and astrocytic transporters was analyzed in the piriform lobe. The DCE-MRI analysis of the piriform lobe identified higher BBBP score in the IE group when compared with controls (34.5% vs 26.5%; P = .02). Activity and expression of MMP9 were increased in the serum, CSF, and piriform lobe of IE dogs as compared with controls. Gene expression of Kir4.1 and claudin-5 in the piriform lobe of IE dogs was significantly lower than in control dogs. Our findings demonstrate BBBD in dogs with IE and were supported by increased MMP9 activity and downregulation of astrocytic potassium channels and some TJ proteins. Blood brain barrier dysfunction may be a novel antiepileptic therapy target.

Zinc Iodide Dimethyl Sulfoxide Reduces Collagen Deposition by Increased Matrix Metalloproteinase-2 Expression and Activity in Lung Fibroblasts.

Chronic inflammatory lung diseases are characterized by disease-specific extracellular matrix accumulation resulting from an imbalance of matrix metalloproteinases (MMPs) and their inhibitors. Zinc is essential for the function of MMPs, and zinc deficiency has been associated with enhanced tissue remodeling. This study assessed if zinc iodide (ZnI) supplementation through dimethyl sulfoxide (DMSO) modifies the action of MMPs in isolated human lung fibroblasts. The expression and activity of two gelatinases, MMP-2 and MMP-9, were determined by gelatin zymography and enzyme-linked immuno-sorbent assay (ELISA). Collagen degradation was determined by cell-based ELISAs. Collagen type I and fibronectin deposition was stimulated by human recombinant tumor growth factor β1 (TGF-β1). Untreated fibroblasts secreted MMP-2 but only minute amounts of MMP-9. TGF-β1 (5 ng/mL) reduced MMP-2 secretion, but stimulated collagen type I and fibronectin deposition. All the effects of TGF-β1 were significantly reduced in cells treated with ZnI-DMSO over 24 h, while ZnI and DMSO alone had a lower reducing effect. ZnI-DMSO alone did not increase MMP secretion but enhanced the ratio of active to inactive of MMP-2. ZnI alone had a lower enhancing effect than ZnI-DMSO on MMP activity. Furthermore, MMP-2 activity was increased by ZnI-DMSO and ZnI in the absence of cells. Soluble collagen type I increased in the medium of ZnI-DMSO- and ZnI-treated cells. Blocking MMP activity counteracted all the effects of ZnI-DMSO. Conclusion: The data suggest that the combination of ZnI with DMSO reduces fibrotic processes by increasing the degradation of collagen type I by up-regulating the activity of gelatinases. Thus, the combination of ZnI with DMSO might be considered for treatment of fibrotic disorders of the lung. DMSO supported the beneficial effects of ZnI.

Flavonoids as dual-action agents for anticancer and anti-tooth caries: a molecular docking and dynamics simulation on MMP2 inhibition

Objective: Cancer pathogenesis is linked to matrix metalloproteinase-2 (MMP2). Numerous studies have indicated an elevated expression of MMP2 in the tissue microenvironment of different cancers, including breast, oral, prostate, ovarian, colorectal, bladder, lung, and hepatocellular carcinoma. The significant role of MMP2 in the degradation of organic compounds in dentin, causing dental caries, has been indicated by accumulating evidence. This study explored the possibility of using flavonoids as natural compounds capable of inhibiting MMP2 to meet the need for new and potent MMP2 inhibitors. Methods: The AutoDock software evaluated the binding energies between selected flavonoids and the MMP2 catalytic domain and ranked the ligands based on their inhibition constant (Ki) values and Gibbs free binding energy scores. The Discovery Studio Visualizer tool demonstrated how the highest-ranked flavonoids interact with the MMP2. Molecular dynamics was conducted for the most potent MMP2 inhibitor in a 100 ns computer simulation. Results: Kaempferol 3-rutinoside-7-sophoroside demonstrated an inhibitory effect against MMP2 with a Ki value and ΔGbinding score of 209.92 fM and −17.30 kcal/mol, respectively. This flavonoid was able to restrict MMP2 activity within a femtomolar range. This study identified eight flavonoids with Ki values in the picomolar range. According to the study, the docked pose of kaempferol 3-rutinoside-7-sophoroside within the MMP2 catalytic domain reached stability after a simulation of ~60 nanoseconds. Conclusion: Inhibition of MMP2 by flavonoids, notably kaempferol derivatives, might be an effective therapeutic strategy for cancer treatment.

#2307 Serum NGAL, MMP-9 and suPAR in the assessment of kidney impairment and cardiovascular risk in children and adolescents with type 1 diabetes or obesity

Abstract Background and Aims Type 1 diabetes mellitus (DM1) and obesity represent two chronic paediatric diseases with worryingly rising incidence, characterized by chronic inflammation, endothelial dysfunction and increased risk for kidney impairment and cardiovascular disease. The aim of this cross-sectional study was to explore the potential usefulness of serum Neutrophil Gelatinase-Associated Lipocalin (NGAL), Matrix Metalloproteinase-9 (MMP-9) and Soluble Urokinase Plasminogen Activator Receptor (suPAR) for predicting early kidney injury or increased cardiovascular risk in children and adolescents with DM1 or obesity. Method Serum samples were obtained from children and adolescents aged <18 years old with DM1 (n=35) or obesity (n=38) and normal renal function with no history of albuminuria, as well as from healthy controls (n=23). Serum NGAL, MMP-9 and suPAR concentrations were measured using commercially available sandwich ELISA kits (NGAL: (DY1757-05), MMP-9: (DMP900); suPAR: (DUP00); R&D systems). All patients were evaluated for anthropometric indices (weight, height, BMI) while for different degrees of weight status we used the body mass index (BMI) z-score adjusted for age and sex. Estimated glomerular filtration rate (eGFR) was calculated according to the revised bedside Schwartz formula. Results Serum NGAL values were found significantly higher in patients with obesity but not in those with DM1. A positive correlation was found in patients with T1DM with diabetes duration (Spearman rho 0.364, p=0.044), and in all study participants with BMI z-score (Spearman rho 0.401, p=0.004). Furthermore, serum MMP-9 levels were significantly increased in patients with T1DM and in patients with obesity compared to controls. Mean serum suPAR levels were significantly higher in patients with obesity compared to patients with T1DM and controls, while children with T1DM had similar suPAR levels to controls (Table 1). Finally, serum suPAR levels showed a negative correlation with age (Spearman rho −0.359, p<0.001) and creatinine levels (Spearman rho −0.334, p=0.005), and a positive correlation with BMI z-score (Spearman rho 0.354, p=0.009). Conclusion Circulating NGAL, MMP-9 levels may prove useful as surrogate biomarkers to creatinine, GFR and albumin excretion rate for early detection of kidney injury, inflammation or endothelial dysfunction and cardiovascular complications in children and adolescents with T1DM or obesity. Children with obesity may have impaired inflammation status, kidney and endothelial function to a higher degree compared to children with T1DM, which may suggest that obesity may impose a greater health burden than T1DM, at least during childhood or the first years after T1DM diagnosis.

Ratiometric Afterglow Luminescent Imaging of Matrix Metalloproteinase-2 Activity via an Energy Diversion Process.

Ratiometric afterglow luminescent (AGL) probes are attractive for in vivo imaging due to their high sensitivity and signal self-calibration function. However, there are currently few ratiometric AGL probes available for imaging enzymatic activity in living organisms. Here, we present an energy diversion (ED) strategy that enables the design of an enzyme-activated ratiometric AGL probe (RAG-RGD) for in vivo afterglow imaging. The ED process provides RAG-RGD with a radiative transition for an 'always on' 520-nm AGL signal (AGL520) and a cascade three-step energy transfer (ET) process for an 'off-on' 710-nm AGL signal (AGL710) in response to a specific enzyme. Using matrix metalloproteinase-2 (MMP-2) as an example, RAG-RGD shows a significant ~11-fold increase in AGL710/AGL520 toward MMP-2. This can sensitively detect U87MG brain tumors through ratiometric afterglow imaging of MMP-2 activity, with a high signal-to-background ratio and deep imaging depth. Furthermore, by utilizing the self-calibration effect of ratiometric imaging, RAG-RGD demonstrated a strong negative correlation between the AGL710/AGL520 value and the size of orthotopic U87MG tumor, enabling accurate monitoring of orthotopic glioma growth in vivo. This ED process may be applied for the design of other enzyme-activated ratiometric afterglow probes for sensitive afterglow imaging.

Evaluation of potential anti-aging effects of Achillea phrygia Boiss. & Balansa (Asteraceae)

This study aims to determine the anti-aging effects of Achillea phrygia, an endemic plant, by evaluating its sun protection factor (SPF) level, antioxidant activity, total phenolic content, extracellular matrix-degrading enzymes (ECM) inhibition, genotoxic/anti-genotoxic, and cytotoxic activities. The SPF level was assessed using an in vitro quantitative method, while antioxidant capacity was determined through DPPH, β-carotene, and hydroxyl-radical (H2O2) scavenging assays. The total phenolic content was quantitatively conducted using the Folin Ciocalteu reagent. The inhibition of ECM-degrading enzymes was determined using matrix metalloproteinase-1 (MMP-1), hyaluronidase, and elastase enzymes. Genotoxic/anti-genotoxic properties were assessed using the AMES Salmonella/microsome assay, and cytotoxicity effects were assessed through the MTT assay. The results indicated that A. phrygia showed moderate SPF activity (SPF = 4.013) and exhibited IC50 values of 0.183 ± 0.03, 0.079 ± 0.51, and 1.18 ± 0.35 mg/mL for DPPH, β-carotene, and hydroxyl-radicals, respectively. The total phenolic content was measured to be 23.56 ± 1.42 mg GAE/g dry extract. Furthermore, the extract demonstrated inhibition of MMP-1 (47.98%) and elastase (39.2%) activities. Importantly, it did not induce DNA damage and showed antigenotoxic activity ranging from 10% to 65.6%. The cytotoxicity assay revealed an IC50 value of 42.41±4.05 µg/mL. These findings suggest that A. phrygia could be utilized as a cosmetic ingredient in skincare products due to its ability to protect against UV radiation, exhibit antioxidant properties, prevent extracellular matrix degradation, and inhibit DNA damage.

Nitric oxide releasing nanofiber stimulates revascularization in response to ischemia via cGMP-dependent protein kinase.

Nitric oxide (NO) promotes angiogenesis via various mechanisms; however, the effective transmission of NO in ischemic diseases is unclear. Herein, we tested whether NO-releasing nanofibers modulate therapeutic angiogenesis in an animal hindlimb ischemia model. Male wild-type C57BL/6 mice with surgically-induced hindlimb ischemia were treated with NO-releasing 3-methylaminopropyltrimethoxysilane (MAP3)-derived or control (i.e., non-NO-releasing) nanofibers, by applying them to the wound for 20 min, three times every two days. The amount of NO from the nanofiber into tissues was assessed by NO fluorometric assay. The activity of cGMP-dependent protein kinase (PKG) was determined by western blot analysis. Perfusion ratios were measured 2, 4, and 14 days after inducing ischemia using laser doppler imaging. On day 4, Immunohistochemistry (IHC) with F4/80 and gelatin zymography were performed. IHC with CD31 was performed on day 14. To determine the angiogenic potential of NO-releasing nanofibers, aorta-ring explants were treated with MAP3 or control fiber for 20 min, and the sprout lengths were examined after 6 days. As per either LDPI (Laser doppler perfusion image) ratio or CD31 capillary density measurement, angiogenesis in the ischemic hindlimb was improved in the MAP3 nanofiber group; further, the total nitrate/nitrite concentration in the adduct muscle increased. The number of macrophage infiltrations and matrix metalloproteinase-9 (MMP-9) activity decreased. Vasodilator-stimulated phosphoprotein (VASP), one of the major substrates for PKG, increased phosphorylation in the MAP3 group. MAP3 nanofiber or NO donor SNAP (s-nitroso-n-acetyl penicillamine)-treated aortic explants showed enhanced sprouting in an ex vivo aortic ring assay, which was partially abrogated by KT5823, a potent inhibitor of PKG. These findings suggest that the novel NO-releasing nanofiber, MAP3 activates PKG and promotes therapeutic angiogenesis in response to hindlimb ischemia.

Topical Application of Autologous Plasma-Derived Plasminogen Accelerates Healing of Chronic Foot Ulcers in Type 2 Diabetes Patients.

Plasminogen (Pg) is currently considered a master regulator of wound healing, but the molecular mechanisms of its efficacy in improving impaired closure of chronic skin ulcers in type 2 diabetes patients remain unclear. Here, we investigated wound healing effects of autologous plasma-derived Pg in diabetes patients with chronic foot ulcers and evaluated Pg-induced changes in levels of key protein markers related to wound repair. Type 2 diabetes patients with chronic wounds of lower extremities were included in the study and received topical applications of Pg in a dose of 1.0 mg/mL every 2 days during 20 days, in addition to the standard wound management treatment. Patients treated only according to conventional protocol served as a control. Wound closure rates were monitored by digital planimetry of wound areas. Plasminogen supplementary treatment significantly accelerated relative wound closure as compared with diabetes patients from the control group (24 ± 4 days vs 120 ± 17 days, respectively, P < .01). As shown by Western blot, Pg application reduced expression of protein regulators of hypoxia events, angiogenesis, and autophagy such as hypoxia-inducible factor-1α (by 6.3-folds, P < .01), angiostatins (by 2.5-folds, P < .05), and autophagy marker LC3-II/LC3-I (by 8.6-folds, P < .05), while increasing vascular endothelial growth factor level by 1.9-folds (P < .05). Gelatin zymography showed that Pg-supplemented therapy decreased activity of matrix metalloproteinase-9 (MMP-9) by 3.5-folds at the end of treatment period (P < .01). We report here for the first time that topically applied plasma-derived Pg has a pronounced beneficial effect in promoting foot ulcer healing in patients with type 2 diabetes through preventing hypoxia-induced signaling, reducing autophagy flux, diminishing excessive MMP activity, and enhancing angiogenesis.

Antioxidant, anti-photoaging, anti-inflammatory, and skin-barrier-protective effects of Gleichenia japonica extract

Ferns native to Korea, such as Davallia mariesii, Dicranopteris pedata, and Gleichenia japonica, possess antioxidant and antibacterial properties. However, their inhibitory effects on skin photoaging have not been demonstrated. Measurement and comparison of the antioxidant activity of three types of ferns revealed that the extract from G. japonica had the best effect. This study evaluates the potential of G. japonica extract as a new functional material for preventing skin damage caused by ultraviolet radiation. G. japonica extracts showed protective effects against ultraviolet B (UVB) radiation in human epidermal keratinocyte cells; the extracts inhibited intracellular reactive oxygen species production. In addition, collagen biosynthesis increased, and matrix metalloproteinase-1 activity and protein expression level decreased in human primary dermal fibroblast irradiated with UVB. The main peak (compound 1) of the extract was separated through high-performance liquid chromatography analysis and preparative liquid chromatography. Compound 1 is strongly inferred to be the main active ingredient because it showed better antioxidant activity and UVB protection effect than G. japonica extract. These results demonstrate the physiological effects of G. japonica extract and suggest its applicability as a new functional substance for preventing skin damage caused by ultraviolet radiation.

Deflamin Attenuated Lung Tissue Damage in an Ozone-Induced COPD Murine Model by Regulating MMP-9 Catalytic Activity.

Chronic obstructive pulmonary disease (COPD) is comprised of histopathological alterations such as pulmonary emphysema and peribronchial fibrosis. Matrix metalloproteinase 9 (MMP-9) is one of the key enzymes involved in both types of tissue remodeling during the development of lung damage. In recent studies, it was demonstrated that deflamin, a protein component extracted from Lupinus albus, markedly inhibits the catalytic activity of MMP-9 in experimental models of colon adenocarcinoma and ulcerative colitis. Therefore, in the present study, we investigated for the first time the biological effect of deflamin in a murine COPD model induced by chronic exposure to ozone. Ozone exposure was carried out in C57BL/6 mice twice a week for six weeks for 3 h each time, and the treated group was orally administered deflamin (20 mg/kg body weight) after each ozone exposure. The histological results showed that deflamin attenuated pulmonary emphysema and peribronchial fibrosis, as evidenced by H&E and Masson's trichrome staining. Furthermore, deflamin administration significantly decreased MMP-9 activity, as assessed by fluorogenic substrate assay and gelatin zymography. Interestingly, bioinformatic analysis reveals a plausible interaction between deflamin and MMP-9. Collectively, our findings demonstrate the therapeutic potential of deflamin in a COPD murine model, and suggest that the attenuation of the development of lung tissue damage occurs by deflamin-regulated MMP-9 catalytic activity.

Association of Matrix Metalloproteinase-2 (MMP-2) and MMP-9 Promoter Variants, Their Serum Levels, and Activities with Aortic Valve Calcification (AVC) in a Population from Western Iran.

Background: Matrix metalloproteinase (MMP) enzyme gene polymorphisms MMP-2-1575G/A and MMP-9-1562C/T promoter polymorphism, their serum levels, and activity are associated with aortic valve calcification (AVC). Materials and Methods: The synergistic link between the risk of AVC and the alleles T and A of MMP-9 and MMP-2 was investigated, respectively. Ninety-two cases with AVC and 92 healthy individuals from the west of Iran were included, and MMP- 2-1575G/A and MMP-9-1562C/T promoter polymorphisms were detected using PCR-RFLP. The serum levels and activity of MMP-2 and -9 were assessed using ELISA and gelatin zymography methods, respectively. In addition, serum biochemical markers, including FBS, urea and creatinine, cholesterol, triglyceride, HDL, LDL, calcium, phosphorus, and blood pressure: systolic blood pressure and diastolic blood pressure were measured. Results: Heart valve calcification disease was associated with a comparatively higher frequency of the A allele of the MMP2-1575 variation (p = 0.002). In addition, the frequency of T allele of the MMP9-1562 variant was higher than the control group (p = 0.007). Conclusion: MMP-2 and MMP-9 serum levels and activities were observed to be considerably higher in the experimental group than in the control group (p < 0.001). Patients are more susceptible to cardiovascular disease than the control group due to elevated serum levels and activity of MMP-2 and MMP-9.

ACE2 and a Traditional Chinese Medicine Formula NRICM101 Could Alleviate the Inflammation and Pathogenic Process of Acute Lung Injury

The coronavirus disease 2019 (COVID-19) is a highly transmittable respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and acute lung injury (ALI) is the major complication of COVID-19. The challenge in studying SARS-CoV-2 pathogenicity is the limited availability of animal model. Therefore, it is necessary to establish animal models that can reproduce multiple characteristics of ALI to study therapeutic application. The present study established a mouse model that has features of ALI that are similar to COVID-19 syndrome to investigate the role of human angiotensin-converting enzyme type II (ACE2) and the administration of the Chinese herbal prescription Chingguan Yihau (NRICM101) in ALI. The mice with ACE2 genetic modifications, including the overexpression of human ACE2 (K18-hACE2 TG) and the absence of ACE2 (mACE2 KO), were intratracheally instillated with hydrochloric acid to induce ALI. The acid intratracheal instillation induced the imbalance between angiotensin-converting enzyme (ACE) and ACE2 (i.e., ACE/ACE2), severe immune cell infiltration, cytokine storms, inflammatory effect, and pulmonary disease in the mice. Compared with K18-hACE2 TG mice, mACE2 KO mice exhibited dramatically increased levels of multiple inflammatory cytokines Interleukin-6 (IL-6) and Tumor necrosis factor alpha (TNF-α) in bronchoalveolar lavage fluid, histological evidence of lung injury, the production of the ACE expression, and the activation of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) expression. The results indicate that overproduction of ACE2 and induction of the ACE2-Ang-(1-7)/Mas axis could counteract the proinflammatory effect of acid-induced ALI and effectively alleviate the pathogenic process of acid-induced ALI by regulating MAPK, p-ERK1/2, and p-STAT3 pathways and dysregulation of MMP-2/MMP-9 activation. In addition, NRICM101, which is an effective TCM that has both antiviral and anti-inflammatory effects against COVID-19, shows potential for treating acid-induced ALI. NRICM101 could alleviate the disease progression of acid-induced ALI by suppressing IL-6 and TNF-α production in alveoli. In conclusion, the established mouse model provided an effective platform for researchers to investigate the role of ACE2 on pathological mechanisms and develop therapeutic strategies for ALI, including COVID-19-related pulmonary diseases. The effects of NRICM101 administration is a potential strategy for curing acid-induced ALI evaluated in the mouse model in this study. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Dexmedetomidine alleviates blood-brain barrier disruption in rats after cerebral ischemia-reperfusion by suppressing JNK and p38 MAPK signaling.

Dexmedetomidine displays multiple mechanisms of neuroprotection in ameliorating ischemic brain injury. In this study, we explored the beneficial effects of dexmedetomidine on blood-brain barrier (BBB) integrity and neuroinflammation in cerebral ischemia/reperfusion injury. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 1.5 h and reperfusion for 24 h to establish a rat model of cerebral ischemia/reperfusion injury. Dexmedetomidine (9 􀁐g/kg) was administered to rats 30 min after MCAO through intravenous injection, and SB203580 (a p38 MAPK inhibitor, 200 􀁐g/kg) was injected intraperitoneally 30 min before MCAO. Brain damages were evaluated by 2,3,5-triphenyltetrazolium chloride staining, hematoxylin-eosin staining, Nissl staining, and brain water content assessment. BBB permeability was examined by Evans blue staining. Expression levels of claudin-5, zonula occludens-1, occludin, and matrix metalloproteinase-9 (MMP-9) as well as M1/M2 phenotypes-associated markers were assessed using immunofluorescence, RT-qPCR, Western blotting, and gelatin zymography. Enzyme-linked immunosorbent assay was used to examine inflammatory cytokine levels. We found that dexmedetomidine or SB203580 attenuated infarct volume, brain edema, BBB permeability, and neuroinflammation, and promoted M2 microglial polarization after cerebral ischemia/reperfusion injury. Increased MMP-9 activity by ischemia/reperfusion injury was inhibited by dexmedetomidine or SB203580. Dexmedetomidine inhibited the activation of the ERK, JNK, and p38 MAPK pathways. Moreover, activation of JNK or p38 MAPK reversed the protective effects of dexmedetomidine against ischemic brain injury. Overall, dexmedetomidine ameliorated brain injury by alleviating BBB permeability and promoting M2 polarization in experimental cerebral ischemia/reperfusion injury model by inhibiting the activation of JNK and p38 MAPK pathways.

Green tea extract suppresses airway inflammation via oxidative stress-driven MAPKs/MMP-9 signaling in asthmatic mice and human airway epithelial cells.

The anti-inflammatory effect of green tea extract (GTE) has been confirmed in asthmatic mice, however, the pharmacological mechanism is not fully elucidated. To investigate the therapeutic efficacy of GTE in asthma and identify specific pathways, murine model of allergic asthma was established by ovalbumin (OVA) sensitization and the challenge for 4 weeks, with oral treatment using GTE and dexamethasone (DEX). Inflammatory cell counts, cytokines, OVA-specific IgE, airway hyperreactivity, and antioxidant markers in the lung were evaluated. Also, pulmonary histopathological analysis and western blotting were performed. In vitro, we established the model by stimulating the human airway epithelial cell line NCI-H292 using lipopolysaccharide, and treating with GTE and mitogen-activated protein kinases (MAPKs) inhibitors. The GTE100 and GTE400 groups showed a decrease in airway hyperresponsiveness and the number of inflammatory cells in the bronchoalveolar lavage fluid (BALF) compared to the OVA group. GTE treatment also reduced interleukin (IL)-13, IL-5, and IL-4 levels in the BALF, and OVA-specific immunoglobulin E levels in the serum compared to those in the OVA group. GTE treatment decreased OVA-induced mucus secretion and airway inflammation. In addition, GTE suppressed the oxidative stress, and phosphorylation of MAPKs, which generally occurs after exposure to OVA. GTE administration also reduced matrix metalloproteinase-9 activity and protein levels. GTE effectively inhibited asthmatic respiratory inflammation and mucus hyperproduction induced by OVA inhalation. These results suggest that GTE has the potential to be used for the treatment of asthma.

N-Terminomic Identification of Intracellular MMP-2 Substrates in Cardiac Tissue.

Proteases are enzymes that induce irreversible post-translational modifications by hydrolyzing amide bonds in proteins. One of these proteases is matrix metalloproteinase-2 (MMP-2), which has been shown to modulate extracellular matrix remodeling and intracellular proteolysis during myocardial injury. However, the substrates of MMP-2 in heart tissue are limited, and lesser known are the cleavage sites. Here, we used degradomics to investigate the substrates of intracellular MMP-2 in rat ventricular extracts. First, we designed a novel, constitutively active MMP-2 fusion protein (MMP-2-Fc) that we expressed and purified from mammalian cells. Using this protease, we proteolyzed ventricular extracts and used subtiligase-mediated N-terminomic labeling which identified 95 putative MMP-2-Fc proteolytic cleavage sites using mass spectrometry. The intracellular MMP-2 cleavage sites identified in heart tissue extracts were enriched for proteins primarily involved in metabolism, as well as the breakdown of fatty acids and amino acids. We further characterized the cleavage of three of these MMP-2-Fc substrates based on the gene ontology analysis. We first characterized the cleavage of sarco/endoplasmic reticulum calcium ATPase (SERCA2a), a known MMP-2 substrate in myocardial injury. We then characterized the cleavage of malate dehydrogenase (MDHM) and phosphoglycerate kinase 1 (PGK1), representing new cardiac tissue substrates. Our findings provide insights into the intracellular substrates of MMP-2 in cardiac cells, suggesting that MMP-2 activation plays a role in cardiac metabolism.

The Antitumoral Effect In Ovo of a New Inclusion Complex from Dimethoxycurcumin with Magnesium and Beta-Cyclodextrin.

Breast cancer is one of the leading causes of death in the female population because of the resistance of cancer cells to many anticancer drugs used. Curcumin has cytotoxic activities against breast cancer cells, although it has limited use due to its poor bioavailability and rapid metabolic elimination. The synthesis of metal complexes of curcumin and curcuminoids is a relevant topic in the search for more active and selective derivatives of these molecular scaffolds. However, solubility and bioavailability are concomitant disadvantages of these types of molecules. To overcome such drawbacks, the preparation of inclusion complexes offers a chemical and pharmacologically safe option for improving the aqueous solubility of organic molecules. Herein, we describe the preparation of the inclusion complex of dimethoxycurcumin magnesium complex (DiMeOC-Mg, (4)) with beta-cyclodextrin (DiMeOC-Mg-BCD, (5)) in the stoichiometric relationship 1:1. This new inclusion complex's solubility in aqueous media phosphate buffer saline (PBS) was improved by a factor of 6x over the free metal complex (4). Furthermore, 5 affects cell metabolic rate, cell morphology, cell migration, induced apoptosis, and downregulation of the matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), and signal transducer and activator of transcription-3 (STAT3) expression levels on MD Anderson metastasis breast-231 cancer (MDA-MB-231) cell lines. Results of an antitumor assay in an in ovo model showed up to 30% inhibition of tumor growth for breast cancer (MDA-MB-231) when using (5) (0.650 mg/kg dose) and 17.29% inhibition with the free homoleptic metal complex (1.5 mg/kg dose, (4)). While the formulation of inclusion complexes from metal complexes of curcuminoids demonstrates its usefulness in improving the solubility and bioavailability of these metallodrugs, the new compound (5) exhibits excellent potential for use as a therapeutic agent in the battle against breast cancer.

Delving into Matrix Metalloproteinase-1 (MMP-1) and its Significance in Periodontal Diseases.

Matrix metalloproteinase-1 (MMP-1) plays a pivotal role in the pathogenesis of periodontal diseases, particularly periodontitis, by virtue of its collagenolytic activity targeting collagen type I, the primary component of periodontal tissues. This review abstract elucidates the intricate involvement of MMP-1 in periodontal tissue homeostasis and its dysregulation in disease states. Elevated MMP-1 levels, observed in gingival tissues and crevicular fluid of individuals with periodontitis, correlate with the degradation of collagen fibers within the periodontium. This degradation contributes to the detachment of teeth from surrounding tissues and exacerbates alveolar bone resorption, hallmark features of periodontal breakdown. Therapeutically, targeting MMP-1 activity emerges as a promising strategy, prompting ongoing research into MMP inhibitors and host modulation therapies. Understanding MMP-1's nuanced role in periodontal diseases paves the way for personalized treatment approaches and holds promise in reshaping periodontal disease management for improved patient outcomes and periodontal health.

Aflatoxin B1 decreased flesh flavor and inhibited muscle development in grass carp (Ctenopharyngodon idella)

In nature, aflatoxins, especially aflatoxin B1 (AFB1), are the common mycotoxins, which cause serious health problems for humans and animals. This paper aimed to study the effects of AFB1 on flesh flavor and muscle development of grass carp (Ctenopharyngodon idella) and its mechanism. There were 1440 individual fish in total, with 6 treatments and each treatment replicated 3 times. The 6 treatments were fed a control diet with different doses of AFB1 (0.04, 29.48, 58.66, 85.94, 110.43 and 146.92 μg/kg diet) for 60 d. AFB1 increased myofiber diameter, as well as decreased myofiber density of grass carp muscle (P < 0.05). The contents of free amino acid decreased gradually (P < 0.05) as dietary AFB1 increased in the muscle of grass carp. The levels of reactive oxygen species, malonaldehyde and protein carbonyl (PC) were increased (P < 0.05) with the dietary AFB1 increased. The levels of antioxidant enzyme (glutathione peroxidase, glutathione, glutathione reductase, total antioxidant capacity, anti-superoxide anion, and anti-hydroxyl radical) were decreased (P < 0.05) with the dietary AFB1 increased. In addition, dietary AFB1 decreased the content of collagen, and downregulated the mRNA and protein levels of transforming growth factor-β (TGF-β)/Smads signaling pathway in grass carp muscle (P < 0.05). The mRNA and protein levels of myogenic regulatory factors were downregulated in grass carp muscle (P < 0.05). Furthermore, the activities of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) were increased (P < 0.05), and the protein levels of phosphorylate-38 mitogen-activated protein kinase (p-p38MAPK), phosphorylate-c-Jun N-terminal kinase, urokinase-type plasminogen activator (uPA), MMP-2 and MMP-9 were upregulated (P < 0.05), but collagen Ⅰ, laminin β1 and fibronectin were downregulated (P < 0.05) with the dietary AFB1 increased in the muscle of grass carp. Based on the results of this study, we can draw the following conclusion: dietary AFB1 might damage flesh flavor and inhibit the muscle development through MAPK/uPA/MMP/extracellular matrix (ECM) signaling pathway in grass carp. Moreover, the recommended safe limit of AFB1 in feed is no more than 26.77 μg/kg diet according to the PC levels in grass carp muscle.

Increased matrix metalloproteinase-2 in ligamentum flavum hypertrophy and the regulation of MMP-2/TIMPs by elastin-derived peptides.

The study aimed to examine matrix metalloproteinase-2 (MMP-2) expression in a rat ligamentum flavum (LF) hypertrophy model in vivo, and the effect of elastin-derived peptides (EDPs) on MMP-2 and tissue inhibitors of metalloproteinases (TIMPs) in rat LF cells in vitro. Surgical destabilization was performed at the rat spinal L3/4 level to induce increased mechanical stress. Rats were killed at 6- and 12-weeks postsurgery for histological staining, immunohistochemical staining, RT-qPCR and western blot. 100 µg/mL EDPs were applied to isolated normal rat LF cells, with or without pretreatment of elastin receptor complex (ERC) inhibitors, to assess the expression of MMP-2, TIMP-1, and TIMP-2. Spinal destabilization led to LF hypertrophy, observed through increased LF thickness and area, along with histological changes of chondrometaplasia and elastic fiber degradation. LF was also stained positively for Col I and Col II, where elastic fiber has broken down. MMP-2 expression was notably elevated in the hypertrophied LF, accompanied by increased TIMP-2 and TIMP-3 levels. EDPs were found to suppress MMP-2 expression and reduce TIMP-1 and TIMP-2 levels in rat LF cells. Interestingly, exposure to EDPs led to a significant rise in MMP-2/TIMP-1 and MMP-2/TIMP-2 ratios, dependent on the ERC. Collectively, the study suggests that increased MMP-2 activity contributes to elastic fiber degradation in hypertrophied LF, generating EDPs that further enhance the MMP-2/TIMPs ratio in LF cells in an ERC-dependent manner. Further research is essential to delve into the mechanisms of EDPs in LF hypertrophy.

Inhibition of melanoma cell migration and invasion by natural coumarin auraptene through regulating EMT markers and reducing MMP-2 and MMP-9 activity

Melanoma, the most invasive form of skin cancer, shows a rising incidence trend in industrial countries. Since the main reason for the failure of current therapeutic approaches against melanoma is metastasis, there is a great interest in introducing effective natural agents to combat melanoma cell migration and invasion. Auraptene (AUR) is the most abundant coumarin derivative in nature with valuable pharmaceutical effects. In this study, we aimed to investigate whether AUR could induce inhibitory effects on the migration and invasion of melanoma cells. B16F10 melanoma cells were treated with different concentrations of AUR and the viability of cells was evaluated by alamarBlue assay. Then, cells were treated with 20 μM AUR, and wound healing, invasion, and adhesion assays were carried out. In addition, the activity of matrix metalloproteinase-2 (MMP-2) and MMP-9 was assessed by gelatin zymography and the expression of genes related to epithelial-mesenchymal transition (EMT) was investigated by qPCR. Finally, the interactions between AUR and MMPs were stimulated by molecular docking. Findings revealed that AUR significantly reduced the migration and invasion of B16F10 cells while improved their adhesion. Furthermore, results of gelatin zymography indicated that AUR suppressed the activity of MMP-2 and MMP-9, and qPCR revealed negative regulatory effect of AUR on the expression of mesenchymal markers including fibronectin and N-cadherin. In addition, molecular docking verified the interactions between AUR and the active sites of wild-type and mutant MMP-2 and MMP-9. Accordingly, AUR could be considered as a potential natural agent with inhibitory effects on the migration and invasion of melanoma cells for future preclinical studies.