Lumican, a Multifunctional Cell Instructive Biomarker Proteoglycan Has Novel Roles as a Marker of the Hypercoagulative State of Long Covid Disease

This study has reviewed the many roles of lumican as a biomarker of tissue pathology in health and disease. Lumican is a structure regulatory proteoglycan of collagen-rich tissues, with cell instructive properties through interactions with a number of cell surface receptors in tissue repair, thereby regulating cell proliferation, differentiation, inflammation and the innate and humoral immune systems to combat infection. The exponential increase in publications in the last decade dealing with lumican testify to its role as a pleiotropic biomarker regulatory protein. Recent findings show lumican has novel roles as a biomarker of the hypercoagulative state that occurs in SARS CoV-2 infections; thus, it may also prove useful in the delineation of the complex tissue changes that characterize COVID-19 disease. Lumican may be useful as a prognostic and diagnostic biomarker of long COVID disease and its sequelae.

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.

Matrix metalloproteinases as therapeutic targets in breast cancer

Matrix metalloproteinases (MMPs) are the most prominent proteinases involved in tumorigenesis. They were initially recognized to promote tumor progression by remodeling the extracellular matrix through their proteolytic activity. However, accumulating evidence has revealed that some MMPs have protective roles in cancer progression, and the same MMP can exert opposing roles depending on the cell type in which it is expressed or the stage of cancer. Moreover, studies have shown that MMPs are involved in cancer progression through their roles in other biological processes such as cell signaling and immune regulation, independent of their catalytic activity. Despite the prognostic significance of tumoral or stromal expression of MMPs in breast cancer, their roles and molecular mechanisms in breast cancer progression remain unclear. As the failures of early clinical trials with broad-spectrum MMP inhibitors were mainly due to a lack of drug specificity, substantial efforts have been made to develop highly selective MMP inhibitors. Some recently developed MMP inhibitory monoclonal antibodies demonstrated promising anti-tumor effects in preclinical models of breast cancer. Importantly, anti-tumor effects of these antibodies were associated with the modulation of tumor immune microenvironment, suggesting that the use of MMP inhibitors in combination with immunotherapy can improve the efficacy of immunotherapy in HER2-positive or triple-negative breast cancer. In this review, the current understanding of the roles of tumoral or stromal MMPs in breast cancer is summarized, and recent advances in the development of highly selective MMP inhibitors are discussed.

Doxycycline Decreases Atherosclerotic Lesions in the Aorta of ApoE-⁄- and Ovariectomized Mice with Correlation to Reduced MMP-2 Activity

Atherogenic events promote changes in vessel walls, with alteration of the redox state, and increased activity of matrix metalloproteinases (MMPs). Thus, this study aims to evaluate aortic remodeling, MMP activity, and reactive oxygen species (ROS) levels after treatment with doxycycline in ApoE-⁄- and ovariectomized mice (OVX). Female ApoE-⁄--knockout mice (5 weeks) were submitted to ovariectomy surgery to induce experimental menopause. They then received chow enriched with 1% cholesterol to induce hypercholesterolemia. The animals were divided into two experimental groups: ApoE-⁄-/OVX vehicle and ApoE-⁄-/OVX doxycycline (30 mg/kg) administered by gavage once a day for 28 days (15th to the 18th week of life). Blood samples were collected to measure total cholesterol and fractions. The aorta was used for morphometry and to measure the activity and expression of MMP-2 and ROS levels. The ApoE-⁄-/OVX doxycycline group showed no change in total and fraction cholesterol levels. However, there was a reduction in ROS levels, MMP-2 expression, and activity that correlated with a decrease in atherosclerotic lesions relative to the ApoE-⁄-/OVX vehicle (p > 0.05). Therefore, we conclude that doxycycline in ApoE-⁄-/OVX animals promotes a reduction in atherosclerotic lesions by reducing ROS and MMP-2 activity and expression.

Lupinus albus Protein Components Inhibit MMP-2 and MMP-9 Gelatinolytic Activity In Vitro and In Vivo

Matrix metalloproteinases 2 and 9 (MMP-2 and MMP-9) are regarded as important clinical targets due to their nodal-point role in inflammatory and oncological diseases. Here, we aimed at isolating and characterizing am MMP-2 and-9 inhibitor (MMPI) from Lupinus albus and at assessing its efficacy in vitro and in vivo. The protein was isolated using chromatographic and 2-D electrophoretic procedures and sequenced by using MALDI-TOF TOF and MS/MS analysis. In vitro MMP-2 and 9 inhibitions were determined on colon adenocarcinoma (HT29) cells, as well as by measuring the expression levels of genes related to these enzymes. Inhibitory activities were also confirmed in vivo using a model of experimental TNBS-induced colitis in mice, with oral administrations of 15 mg·kg^-1. After chromatographic and electrophoretic isolation, the L. albus MMP-9 inhibitor was found to comprise a large fragment from δ-conglutin and, to a lower extent, small fragments of β-conglutin. In vitro studies showed that the MMPI successfully inhibited MMP-9 activity in a dose-dependent manner in colon cancer cells, with an IC50 of 10 µg·mL^-1 without impairing gene expression nor cell growth. In vivo studies showed that the MMPI maintained its bioactivities when administered orally and significantly reduced colitis symptoms, along with a very significant inhibition of MMP-2 and -9 activities. Overall, results reveal a novel type of MMPI in lupine that is edible, proteinaceous in nature and soluble in water, and effective in vivo, suggesting a high potential application as a nutraceutical or a functional food in pathologies related to abnormally high MMP-9 activity in the digestive system.

Synthesis and Bioactivity of Ancorinoside B, a Marine Diglycosyl Tetramic Acid

The sponge metabolite ancorinoside B was prepared for the first time in 16 steps and 4% yield. It features a β-d-galactopyranosyl-(1→4)-β-d-glucuronic acid tethered to a d-aspartic acid-derived tetramic acid. Key steps were the synthesis of a fully protected d-lactose derived thioglycoside, its attachment to a C20-aldehyde spacer, functionalization of the latter with a terminal N-(β-ketoacyl)-d-aspartate, and a basic Dieckmann cyclization to close the pyrrolidin-2,4-dione ring with concomitant global deprotection. Ancorinoside B exhibited multiple biological effects of medicinal interest. It inhibited the secretion of the cancer metastasis-relevant matrix metalloproteinases MMP-2 and MMP-9, and also the growth of Staphylococcus aureus biofilms by ca 87% when applied at concentrations as low as 0.5 µg/mL. This concentration is far below its MIC of ca 67 µg/mL and thus unlikely to induce bacterial resistance. It also led to a 67% dispersion of preformed S. aureus biofilms when applied at a concentration of ca 2 µg/mL. Ancorinoside B might thus be an interesting candidate for the control of the general hospital, catheter, or joint protheses infections.

Extended Cheese Whey Fermentation Produces a Novel Casein-Derived Antibacterial Polypeptide That Also Inhibits Gelatinases MMP-2 and MMP-9

Our previous works produced a whey fermentation methodology that yielded antibacterial activity and potential inhibition of matrix metalloproteases (MMP)-2 and -9. Here, we evaluated if these activities were due to fermentation-produced peptides. Prolonged fermentation was carried out in the presence of our specific lactic acid bacteria (LAB) consortium. LAB fermentation yielded a total of 11 polypeptides, which were predominantly produced after 6 days of fermentation. One which was derived from beat casein presented a particularly high antibacterial activity against food pathogenic bacteria and was more effective than standard food disinfectants. This polypeptide was further studied and was also found to be active against several strains of pathogenic bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), in a dose-dependent manner. It also inhibited MMP-2 and MMP-9 whilst reducing HT29 cancer cell migration in vitro. Overall, this novel whey-derived polypeptide presents dual antibacterial and anti-inflammatory activity, revealing a strong potential to be used in functional foods or as a nutraceutical. Its identification and further characterization can open novel perspectives in the field of preventive/curative diets related to gut microbiota, gut inflammation, and cancer prevention, particularly if used in in vivo studies.

Monitoring matrix remodeling in the cellular microenvironment using microrheology for complex cellular systems

Multiple particle tracking (MPT) microrheology was employed for monitoring the development of extracellular matrix (ECM) mechanical properties in the direct microenvironment of living cells. A customized setup enabled us to overcome current limitations: (i) Continuous measurements were enabled using a cell culture chamber, with this, matrix remodeling by fibroblasts in the heterogeneous environment of macroporous scaffolds was monitored continuously. (ii) Employing tracer laden porous scaffolds for seeding human mesenchymal stem cells (hMSCs), we followed conventional differentiation protocols. Thus, we were, for the first time able to study the massive alterations in ECM elasticity during hMSC differentiation. (iii) MPT measurements in 2D cell cultures were enabled using a long distance objective. Exemplarily, local mechanical properties of the ECM in human umbilical vein endothelial cell (HUVEC) cultures, that naturally form 2D layers, were investigated scaffold-free. Using our advanced setup, we measured local, apparent elastic moduli G_0,app in a range between 0.08 and 60 Pa. For fibroblasts grown in collagen-based scaffolds, a continuous decrease of local matrix elasticity resulted during the first 10 hours after seeding. The osteogenic differentiation of hMSC cells cultivated in similar scaffolds, led to an increase of G_0,app by 100 %, whereas after adipogenic differentiation it was reduced by 80 %. The local elasticity of ECM that was newly secreted by HUVECs increased significantly upon addition of protease inhibitor and in high glucose conditions even a twofold increase in G_0,app was observed. The combination of these advanced methods opens up new avenues for a broad range of investigations regarding cell-matrix interactions and the propagation of ECM mechanical properties in complex biological systems. STATEMENT OF SIGNIFICANCE: Cells sense the elasticity of their environment on a micrometer length scale. For studying the local elasticity of extracellular matrix (ECM) in the direct environment of living cells, we employed an advanced multipleparticle tracking microrheology setup. MPT is based on monitoring the Brownian motion oftracer particles, which is restricted by the surrounding network. Network elasticity can thusbe quantified. Overcoming current limitations, we realized continuous investigations of ECM elasticityduring fibroblast growth. Furthermore, MPT measurements of stem cell ECM showed ECMstiffening during osteogenic differentiation and softening during adipogenic differentiation.Finally, we characterized small amounts of delicate ECM newly secreted in scaffold-freecultures of endothelial cells, that naturally form 2D layers.

Design, synthesis, and biological evaluation of 4-phenoxybenzenesulfonyl pyrrolidine derivatives as matrix metalloproteinase inhibitors

A series of 4-phenoxybenzenesulfonyl pyrrolidine derivatives were designed, synthesized, and evaluated as matrix metalloproteinases (MMPs) inhibitors. All of the synthesized compounds displayed inhibitory activity against MMP-2 and MMP-9. Compounds 4a, 4e, and 4i displayed more potent activity than the other compounds. While the three compounds mildly or moderately inhibited the proliferation of cancer cells, they significantly suppressed the migration and invasion of cancer cells at relatively low concentrations as determined by a wound healing assay and transwell assay. In addition, compound 4e suppressed vascular endothelial cell tube formation and sprouting of microvessels from aortic rings in vitro in a dose-dependent manner. Compound 4e markedly suppressed the pulmonary metastasis of H22 cells in mice. These findings along with molecular docking results suggested that compound 4e might be a promising candidate for further structural optimization to develop MMP inhibitors as potential anticancer agents.

Andrographolide as a Therapeutic Agent Against Breast and Ovarian Cancers

Andrographolide (ANDR), isolated from Andrographis paniculata, is a medicinal compound effective against infections, inflammatory disorders, and various cancers. In the present study, the effects of ANDR on NFkB (nuclear factor kappa-light-chain-enhancer of activated B cells) activation, caspase-8-mediated apoptosis and pyroptosis, and extra cellular matrix (ECM) degradation were analyzed in A431, MDA-MB231, and SKOV-3 cell lines. Results showed that ANDR inhibited the growth and proliferation of cancer cell lines by inhibiting NFkB signaling. A significant decrease in phospho-p65 level was observed upon increasing ANDR concentration in epidermoid carcinoma and breast cancer cell lines, A431 and MDA-MB231, respectively. Accordingly, upon ANDR treatment, the expression of caspase-8 was increased, whereas no significant induction of caspase-1 expression was observed. Moreover, we observed a significant increase in the expression of tissue inhibitor of metallopeptidase-1 (TIMP1) upon increasing ANDR concentration. Such induction of TIMP1 inhibited the activity of matrix metallopeptidase-7 (MMP-7), thus preventing the degradation of ECM. Therefore, as ANDR shows cytotoxicity towards cancer cells via the NFkB signal transduction pathway without inducing pyroptosis and blocks breast and ovarian cancer invasion by inhibiting MMP-7 expression through TIMP1 up-regulation, it has the potential to be developed as a drug targeting ovarian and breast cancers.

MMP targeting in the battle for vision: Recent developments and future prospects in the treatment of diabetic retinopathy

Matrix metalloproteinases (MMPs) are enzymes capable of degrading nearly all types of extracellular matrix. They perform a wide range of roles in physiological processes, which is the reason for their strict regulation by numerous mechanisms including natural tissue inhibitors of metalloproteinases (TIMP). Research only started to shed light on more troublesome aspects of MMPs function, like cancer progression, Alzheimer's disease, atherosclerosis, ageing. Moreover, their profound role in diabetes is being carefully investigated including one of its most debilitating complications - diabetic retinopathy (DR), the leading cause of acquired blindness worldwide. Traditional treatment of this condition seems to be only mildly satisfactory, which elicited substantial interest in the field of new therapeutic methods including MMP targeting. So far, significant roles of MMP-2 and MMP-9 in the development of retinopathy have been established, with special attention given to the process of blood-retinal barrier impairment. Further exploration revealed MMP-10 and MMP-14 involvement as well as changes in MMP/TIMP ratio. In this review, we provide insight into MMPs role in diabetic retinopathy with a clarification of various mechanisms regulating MMP activity in the light of the recent studies. We conclude with an overview of novel DR therapies targeting MMPs and point to the need of further examination of their usefulness in clinical setting, with an eye towards future research.

Targeting M3 Muscarinic Receptors for Colon Cancer Therapy

BACKGROUND

Expression and activation of subtype-3 muscarinic receptors (M3R) plays an important role in the progression of colorectal neoplasia.

METHOD

Herein, we describe the role of muscarinic receptors in colon cancer, focusing specifically on M3R, illustrate how M3R over-expression and activation of post-receptor signaling pathways potentiates tumor progression, and explore the efficacy and safety of a variety of therapeutic approaches that can target the molecules involved.

RESULTS

Colon cancers overexpress M3R mRNA (CHRM3) and protein, and post-M3R signaling stimulates cell proliferation. Post-M3R signal transduction is complex, involving interplay between epidermal growth factor receptors (EGFR)/ERK and protein kinase C (PKC)/p38 mitogen-activated protein (MAP) kinase signaling pathways. In particular, the development of an invasive and metastatic phenotype requires that these signaling interactions augment cellular release of a key collagenase, matrix metalloproteinase-1 (MMP1). Blocking either M3R activation or post-M3R signaling attenuates MMP1 release and colon cancer invasiveness.

CONCLUSION

Parsing the complexities of these signaling interactions is important, not only to understand these mechanisms of cancer initiation and progression, but also to develop novel treatment modalities. Since the vast majority of persons with colon cancer die from disseminated disease, preventing or reversing metastatic spread of cancer cells by targeting M3R, post-M3R signaling, or MMP1 has therapeutic potential.

Clusterin from human clinical tear samples: Positive correlation between tear concentration and Schirmer strip test results

PURPOSE

To investigate the relationship between tear concentration of the homeostatic protein clusterin (CLU) and dry eye signs and symptoms, and to characterize tear CLU protein.

METHODS

Two independent studies were conducted, one in Tucson (44 subjects), the other in Los Angeles (52 subjects). A cohort study design was employed to enroll patients without regard to dry eye diagnosis. Dry eye signs and symptoms were assessed using clinical tests. Tear samples were collected by Schirmer strip, and also by micropipette at slit lamp when possible. CLU from both sample types was quantified by immunoassay. The relationship between CLU concentration and clinical test scores was determined by Pearson's correlation coefficient (for individual eyes) and multiple linear regression analysis (including both eyes). CLU was also evaluated biochemically by western blotting.

RESULTS

In the Tucson cohort, a positive correlation was observed between tear CLU concentration and results of the Schirmer strip test, a measure of tear flow (p = 0.021 includes both eyes). This result was corroborated in the Los Angeles cohort (p = 0.013). The mean tear CLU concentration was 31 ± 14 μg/mL (n = 18 subjects, 33 eyes; range = 7-48 μg/mL). CLU from clinical tear samples appeared biochemically similar to CLU from a non-clinical tear sample and from blood plasma.

CONCLUSIONS

Results support the hypothesis that an optimal concentration of tear CLU is important for ocular surface health, and that this drops below the effective threshold in dry eye. Tear CLU measurement might identify patients that could benefit from supplementation. Information about concentration will aid development of therapeutic dosage parameters.

Synthesis and biological evaluation of novel benzofuroxan-based pyrrolidine hydroxamates as matrix metalloproteinase inhibitors with nitric oxide releasing activity

On the basis of the strategy of "multifunctional drugs", a series of novel matrix metalloproteinase inhibitors (MMPIs) containing benzofuroxan scaffold as a nitric oxide donor were designed, synthesized and evaluated. All synthesized compounds, especially 16a, exhibited potent MMP-2,9 inhibitory activities, anti-proliferative activities and could produce high levels of NO in Hela cells. They were also evaluated for both of their anti-invasion and anti-angiogenesis effects. Furthermore, compared with LY52, 16a demonstrated competitive antitumor activity in vivo. These hybrid NO-MMPIs might offer suitable scaffolds to develop valuable MMP inhibitors for the further discovery of novel anti-cancer drugs.

Cutting to the Chase: How Matrix Metalloproteinase-2 Activity Controls Breast-Cancer-to-Bone Metastasis

Bone metastatic breast cancer is currently incurable and will be evident in more than 70% of patients that succumb to the disease. Understanding the factors that contribute to the progression and metastasis of breast cancer can reveal therapeutic opportunities. Matrix metalloproteinases (MMPs) are a family of proteolytic enzymes whose role in cancer has been widely documented. They are capable of contributing to every step of the metastatic cascade, but enthusiasm for the use of MMP inhibition as a therapeutic approach has been dampened by the disappointing results of clinical trials conducted more than 20 years ago. Since the trials, our knowledge of MMP biology has expanded greatly. Combined with advances in the selective targeting of individual MMPs and the specific delivery of therapeutics to the tumor microenvironment, we may be on the verge of finally realizing the promise of MMP inhibition as a treatment strategy. Here, as a case in point, we focus specifically on MMP-2 as an example to show how it can contribute to each stage of breast-cancer-to-bone metastasis and also discuss novel approaches for the selective targeting of MMP-2 in the setting of the bone-cancer microenvironment.

Dual function of proanthocyanidins as both MMP inhibitor and crosslinker in dentin biomodification: A literature review

Proanthocyanidin, a natural phytochemical bioactive agent, simultaneously can silence the activity of dentinal proteases and crosslink the collagen matrix; both of these phenomena would be the fundamentals for bio-stability of resin-dentin interface which is essential for a promising adhesive dentistry. This review provides an overview of the data developed by different groups of researchers and highlighted topics are proanthocyanidin chemistry, natural resources and the unique interactions between proanthocyanidincollagen and proanthocyanidin-MMPs in dentin. Besides, clinical applications of proanthocyanidin in the form of proanthocyanidin-containing adhesives, preconditioners and etchants have been reviewed. One hundred and twelve studies have been published in peer-reviewed journals from 1981 to 2017, all were comprised in this review, some of them have been actually proven to be promising from clinical point of view and others need further assessment before their adoption as clinically practicable protocols.

Chitosan-doxycycline hydrogel: An MMP inhibitor/sclerosing embolizing agent as a new approach to endoleak prevention and treatment after endovascular aneurysm repair

The success of endovascular repair of abdominal aortic aneurysms remains limited due to the development of endoleaks. Sac embolization has been proposed to manage endoleaks, but current embolizing materials are associated with frequent recurrence. An injectable agent that combines vascular occlusion and sclerosing properties has demonstrated promise for the treatment of endoleaks. Moreover, the inhibition of aneurysmal wall degradation via matrix metalloproteinases (MMPs) may further prevent aneurysm progression. Thus, an embolization agent that promotes occlusion, MMP inhibition and endothelial ablation was hypothesized to provide a multi-faceted approach for endoleak treatment. In this study, an injectable, occlusive chitosan (CH) hydrogel containing doxycycline (DOX)-a sclerosant and MMP inhibitor-was developed. Several CH-DOX hydrogel formulations were characterized for their mechanical and sclerosing properties, injectability, DOX release rate, and MMP inhibition. An optimized formulation was assessed for its short-term ability to occlude blood vessels in vivo. All formulations were injectable and gelled rapidly at body temperature. Only hydrogels prepared with 0.075M sodium bicarbonate and 0.08M phosphate buffer as the gelling agent presented sufficient mechanical properties to immediately impede physiological flow. DOX release from this gel was in a two-stage pattern: a burst release followed by a slow continuous release. Released DOX was bioactive and able to inhibit MMP-2 activity in human glioblastoma cells. Preliminary in vivo testing in pig renal arteries showed immediate and delayed embolization success of 96% and 86%, respectively. Altogether, CH-DOX hydrogels appear to be promising new multifunctional embolic agents for the treatment of endoleaks.

STATEMENT OF SIGNIFICANCE

An injectable embolizing chitosan hydrogel releasing doxycycline (DOX) was developed as the first multi-faceted approach for the occlusion of blood vessels. It combines occlusive properties with DOX sclerosing and MMP inhibition properties, respectively known to prevent recanalization process and to counteract the underlying pathophysiology of vessel wall degradation and aneurysm progression. After drug release, the biocompatible scaffold can be invaded by cells and slowly degrade. Local DOX delivery requires lower drug amount and decreases risks of side effects compared to systemic administration. This new gel could be used for the prevention or treatment of endoleaks after endovascular aneurysm repair, but also for the embolization of other blood vessels such as venous or vascular malformations.

Effect of matrix metalloproteinase inhibitor on disrupted E-cadherin after acid exposure in the human nasal epithelium

OBJECTIVE

Laryngopharyngeal reflux disease (LPRD) is one of potential factors in recalcitrant chronic rhinosinusitis with or without polyps. An increase in junctional permeability in the nasal mucosa in LPRD may be due to disrupted protein bridge formation with cell-to-cell adhesion molecules such as E-cadherin. Despite the relationship between nasal mucosal inflammation and LPRD, the clear mechanism by which acid reflux affects the nasal epithelium remains unclear.

METHODS

The expression levels and distribution patterns of E-cadherin in primary culture of nasal epithelial cells after acid exposure with or without dexamethasone and matrix metalloproteinase (MMP) inhibitor were determined using Western blot and immunocytochemistry. The functional roles of MMP inhibitor in maintaining junctional permeability in the nasal epithelium were elucidated by transepithelial permeability test.

RESULTS

By acid exposure to nasal epithelial cells, mature E-cadherin was decreased and cleaved E-cadherin was increased. This was thought to be caused by cleavage of mature E-cadherin between cells and was confirmed by the increment of E-cadherin inside a cell in immunocytochemical evaluation. Whereas disruption of E-cadherin was not recovered by steroid medication with various treatments of dexamethasone, disrupted E-cadherin was restored to normal by inhibition of MMPs with actinonin, a broad MMP inhibitor. This recovery was functionally demonstrated by transepithelial permeability test.

CONCLUSION

Our results suggest that altered expression of E-cadherin in the nasal epithelium by acid exposure may be a possible mechanism for nasal tissue injury in chronic nasal inflammation with LPRD, and that MMP inhibition is a potential treatment.

LEVEL OF EVIDENCE

NA. Laryngoscope, 128:E1-E7, 2018.

Effectiveness of pre-treatment with chlorhexidine in restoration retention: A 36-month follow-up randomized clinical trial

OBJECTIVES

This study evaluated the effect of the pre-treatment with 2% chlorhexidine digluconate (CHX) as coadjutant in restoration retention of noncarious cervical lesions (NCCL), after 36 months of follow-up.

METHODS

A randomized controlled split-mouth and triple-blind (operators, patients and evaluator) trial was carried out. Patients (n=42) with at least two non-carious cervical lesions were included. The teeth with NCCL were randomly assigned to two treatment groups: application of 2% CHX (experimental group) or a placebo solution (control group) for 60s after acid etching and before the adhesive application. A trained and calibrated examiner evaluated the restorations at baseline (1 week) and at each recall (6, 12, 24 and 36 months) using the FDI criteria. A total of 225 restorations were evaluated after 36-month follow-up. Data were subjected to survival analysis using the Kaplan-Meier method, and the log-rank test was used to evaluate the existence of differences between the survival curves (α=0.05).

RESULTS

The restorations survival rate after 36 months of follow-up was 76.1%. There was no difference in the retention and failure rates between the experimental and the control group (p=0.968). There was an increased failure trend when restorations were located subgingival compared to those at the gingival level or supragingival.

CONCLUSION

The pre-treatment with 2% chlorhexidine digluconate did not promote further restoration retention of noncarious cervical lesions.

CLINICAL SIGNIFICANCE

The cavity pre-treatment with chlorhexidine for inhibition of hybrid layer degradation does not add any beneficial effect to the clinical performance of restorations.

Nanoparticulate delivery of agents for induced elastogenesis in three-dimensional collagenous matrices

The degradation of elastic matrix in the infrarenal aortic wall is a critical parameter underlying the formation and progression of abdominal aortic aneurysms. It is mediated by the chronic overexpression of matrix metalloprotease (MMP)-2 and MMP-9, leading to a progressive loss of elasticity and weakening of the aortic wall. Delivery of therapeutic agents to inhibit MMPs, while concurrently coaxing cell-based regenerative repair of the elastic matrix represents a potential strategy for slowing or arresting abdominal aortic aneurysm growth. Previous studies have demonstrated elastogenic induction of healthy and aneurysmal aortic smooth muscle cells and inhibition of MMPs, following exogenous delivery of elastogenic factors such as transforming growth factor (TGF)-β1, as well as MMP-inhibitors such as doxycycline (DOX) in two-dimensional culture. Based on these findings, and others that demonstrated elastogenic benefits of nanoparticulate delivery of these agents in two-dimensional culture, poly(lactide-co-glycolide) nanoparticles were developed for localized, controlled and sustained delivery of DOX and TGF-β1 to human aortic smooth muscle cells within a three-dimensional gels of type I collagen, which closely simulate the arterial tissue microenvironment. DOX and TGF-β1 released from these nanoparticles influenced elastogenic outcomes positively within the collagen constructs over 21 days of culture, which were comparable to that induced by exogenous supplementation of DOX and TGF-β1 within the culture medium. However, this was accomplished at doses ~20-fold lower than the exogenous dosages of the agents, illustrating that their localized, controlled and sustained delivery from nanoparticles embedded within a three-dimensional scaffold is an efficient strategy for directed elastogenesis. Copyright © 2014 John Wiley & Sons, Ltd.

Antibody-dependent CD56+ T cell responses are functionally impaired in long-term HIV-1 infection

Background

Antibody-dependent cellular cytotoxicity (ADCC), which mainly mediated by natural killer (NK) cells, may play a critical role in slowing human immunodeficiency virus type-1 (HIV-1) disease progression and protecting from HIV-1 infection. Besides classic NK cells, CD56+ T cells also have some NK cell-like properties, such as the large granular lymphocyte morphology and the capacity to destroy NK-sensitive target cells. However, little is known about the potentials of antibody-dependent CD56+ T cell responses and the association between antibody-dependent CD56+ T cell responses and HIV-1 disease progression.

Results

In the present study, we showed evidences that, in addition to NK cells, CD56+ T cells could generate degranulation upon CD16 cross-linking. Ex vivo study showed that FcγRIII (CD16)-mediated CD56+ T cell responses were distinctly induced by IgG antibody-bound P815 cells. Comparatively, CD56− T cells and invariant NKT (CD3+ 6B11+) failed to induce antibody-dependent activation. Antibody-dependent CD56+ T cell responses were mainly ascribed to CD4/CD8 double negative subset and were functionally impaired in long-term HIV-1-infected former plasma donors, regardless of hepatitis C virus (HCV) coinfection status. Also, CD56+ T cell-mediated HIV-1-specific antibody-dependent responses were declined in men who have sex with men with HIV-1 infection over 3 years. Finally, we showed that matrix metalloprotease (MMP) inhibitor GM6001 could partially restored antibody-dependent CD56+ T cell responses of chronic HIV-1-infected subjects.

Conclusions

Our results suggested that CD56+ T cells could mediate ADCC responses and the responses were impaired in chronic HIV-1 infection.

Electronic supplementary material

The online version of this article (doi:10.1186/s12977-016-0313-6) contains supplementary material, which is available to authorized users.

Pneumococcal Infection Aggravates Elastase-Induced Emphysema via Matrix Metalloproteinase 12 Overexpression

BACKGROUND

Acute exacerbation of chronic obstructive pulmonary disease (COPD)--typically caused by bacterial or viral infection--is associated with poor prognosis and emphysema progression through unknown mechanisms. We aimed to elucidate the mechanisms responsible for the poor prognosis and emphysema progression associated with COPD exacerbation.

METHODS

We established a mouse model mimicking acute human COPD exacerbation, wherein mice with elastase-induced emphysema were intranasally infected with Streptococcus pneumoniae.

RESULTS

In mice with elastase-induced emphysema, infection with S. pneumoniae resulted in increased mortality, an increased number of inflammatory cells in bronchoalveolar lavage fluid (BALF), and increased matrix metalloproteinase 12 (MMP-12) production in the lungs, as well as enhanced emphysema progression. The increased MMP-12 production was mostly due to alveolar type II cells, alveolar macrophages, and lymphocytes that aggregated around vessels and bronchioles. Dexamethasone treatment suppressed the mortality rate and number of inflammatory cells in BALF but not emphysema progression, possibly owing to the failure of MMP-12 suppression in the lungs, whereas treatment with the MMP inhibitor ONO-4817 dramatically suppressed both mortality rate and emphysema progression.

CONCLUSIONS

These results suggest that MMP-12 production during COPD exacerbation results in increased mortality and emphysema progression. Our study identifies MMP-12 as a target to prevent further aggravation of COPD.

Comparison of the Effects of Matrix Metalloproteinase Inhibitors on TNF-α Release from Activated Microglia and TNF-α Converting Enzyme Activity

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases that regulate cell-matrix composition and are also involved in processing various bioactive molecules such as cell-surface receptors, chemokines, and cytokines. Our group recently reported that MMP-3, -8, and -9 are upregulated during microglial activation and play a role as proinflammatory mediators (Lee et al., 2010, 2014). In particular, we demonstrated that MMP-8 has tumor necrosis factor alpha (TNF-α)-converting enzyme (TACE) activity by cleaving the prodomain of TNF-α and that inhibition of MMP-8 inhibits TACE activity. The present study was undertaken to compare the effect of MMP-8 inhibitor (M8I) with those of inhibitors of other MMPs, such as MMP-3 (NNGH) or MMP-9 (M9I), in their regulation of TNF-α activity. We found that the MMP inhibitors suppressed TNF-α secretion from lipopolysaccharide (LPS)-stimulated BV2 microglial cells in an order of efficacy: M8I>NNGH>M9I. In addition, MMP inhibitors suppressed the activity of recombinant TACE protein in the same efficacy order as that of TNF-α inhibition (M8I>NNGH>M9I), proving a direct correlation between TACE activity and TNF-α secretion. A subsequent pro-TNF-α cleavage assay revealed that both MMP-3 and MMP-9 cleave a prodomain of TNF-α, suggesting that MMP-3 and MMP-9 also have TACE activity. However, the number and position of cleavage sites varied between MMP-3, -8, and -9. Collectively, the concurrent inhibition of MMP and TACE by NNGH, M8I, or M9I may contribute to their strong anti-inflammatory and neuroprotective effects.

Hydroxamic acid - A novel molecule for anticancer therapy

Hydroxamic acid is a potent moiety not only in the field of cancer therapy but also as a mutagenic agent. Among the various derivatives of hydroxamic acid, SAHA (Suberoylanilide Hydroxamic Acid) is considered as a potent anticancer agent. Scientists from the different corner synthesized different hydroxamic acid moieties with some straight chain oxazole, thiadiazole, biphenyl moieties in the terminal position. Acetylation and deacetylation of histones of the core proteins of nucleosomes in chromatin play an important role in the regulation of gene expression. The level of acetylation of histones is established and maintained by two classes of enzymes, histone acetyltransferase and histone deacetylases, which have been identified as transcriptional coactivators and transcriptional corepressors, respectively. There is increasing evidence that aberrant histone acetylation has been linked to various malignant diseases. Great efforts are currently underway for the design of more potent and less toxic candidates for the treatment of cancer. In recent years, hydroxamic acid derivatives have attracted increasing attention for their potential as highly efficacious in combating various etiological factors associated with cancer. Our main intention to draw an attention is that this single functional moiety has not only fit in the receptor but also create a diversified activity.