Selective toxicity of antibacterial agents-still a valid concept or do we miss chances and ignore risks?

BACKGROUND: Selective toxicity antibacteribiotics is considered to be due to interactions with targets either being unique to bacteria or being characterized by a dichotomy between pro- and eukaryotic pathways with high affinities of agents to bacterial- rather than eukaryotic targets. However, the theory of selective toxicity oversimplifies the complex modes of action of antibiotics in pro- and eukaryotes. METHODS AND OBJECTIVE: This review summarizes data describing multiple modes of action of antibiotics in eukaryotes. RESULTS: Aminoglycosides, macrolides, oxazolidinones, chloramphenicol, clindamycin, tetracyclines, glycylcyclines, fluoroquinolones, rifampicin, bedaquillin, ß-lactams inhibited mitochondrial translation either due to binding to mitosomes, inhibition of mitochondrial RNA-polymerase-, topoisomerase 2ß-, ATP-synthesis, transporter activities. Oxazolidinones, tetracyclines, vancomycin, ß-lactams, bacitracin, isoniazid, nitroxoline inhibited matrix-metalloproteinases (MMP) due to chelation with zinc and calcium, whereas fluoroquinols fluoroquinolones and chloramphenicol chelated with these cations, too, but increased MMP activities. MMP-inhibition supported clinical efficacies of ß-lactams and daptomycin in skin-infections, and of macrolides, tetracyclines in respiratory-diseases. Chelation may have contributed to neuroprotection by ß-lactams and fluoroquinolones. Aminoglycosides, macrolides, chloramphenicol, oxazolidins oxazolidinones, tetracyclines caused read-through of premature stop codons. Several additional targets for antibiotics in human cells have been identified like interaction of fluoroquinolones with DNA damage repair in eukaryotes, or inhibition of mucin overproduction by oxazolidinones. CONCLUSION: The effects of antibiotics on eukaryotes are due to identical mechanisms as their antibacterial activities because of structural and functional homologies of pro- and eukaryotic targets, so that the effects of antibiotics on mammals are integral parts of their overall mechanisms of action.

The SARS-CoV-2 spike protein alters barrier function in 2D static and 3D microfluidic in-vitro models of the human blood-brain barrier.

As researchers across the globe have focused their attention on understanding SARS-CoV-2, the picture that is emerging is that of a virus that has serious effects on the vasculature in multiple organ systems including the cerebral vasculature. Observed effects on the central nervous system include neurological symptoms (headache, nausea, dizziness), fatal microclot formation and in rare cases encephalitis. However, our understanding of how the virus causes these mild to severe neurological symptoms and how the cerebral vasculature is impacted remains unclear. Thus, the results presented in this report explored whether deleterious outcomes from the SARS-CoV-2 viral spike protein on primary human brain microvascular endothelial cells (hBMVECs) could be observed. The spike protein, which plays a key role in receptor recognition, is formed by the S1 subunit containing a receptor binding domain (RBD) and the S2 subunit. First, using postmortem brain tissue, we show that the angiotensin converting enzyme 2 or ACE2 (a known binding target for the SARS-CoV-2 spike protein), is ubiquitously expressed throughout various vessel calibers in the frontal cortex. Moreover, ACE2 expression was upregulated in cases of hypertension and dementia. ACE2 was also detectable in primary hBMVECs maintained under cell culture conditions. Analysis of cell viability revealed that neither the S1, S2 or a truncated form of the S1 containing only the RBD had minimal effects on hBMVEC viability within a 48 h exposure window. Introduction of spike proteins to invitro models of the blood-brain barrier (BBB) showed significant changes to barrier properties. Key to our findings is the demonstration that S1 promotes loss of barrier integrity in an advanced 3D microfluidic model of the human BBB, a platform that more closely resembles the physiological conditions at this CNS interface. Evidence provided suggests that the SARS-CoV-2 spike proteins trigger a pro-inflammatory response on brain endothelial cells that may contribute to an altered state of BBB function. Together, these results are the first to show the direct impact that the SARS-CoV-2 spike protein could have on brain endothelial cells; thereby offering a plausible explanation for the neurological consequences seen in COVID-19 patients.

Antimetastatic Properties of Tea Polyphenols.

Metastasis of cells from primary site to distant organs involves a series of sequential steps, and molecules responsible for all these events are understandably considered as potential targets for metastasis management. Tea polyphenols, the secondary metabolites of the tea leaf Camellia sinensis, are increasingly being studied for their antimetastatic properties. In this article, effects of green tea polyphenols (GTP) and black tea polyphenols (BTP) on the molecules and events involved in metastasis are discussed in detail. As tea is a very popular beverage, tea polyphenols are expected to be potential chemopreventive agents that can be taken with normal diet and can be nontoxic due to their natural origin. However, individual variations in metabolic pathways, bioavailability, dose, and toxicity are some important factors that can modify the effectiveness of tea polyphenols within the human system.

A Network Pharmacology Analysis of the Active Components of the Traditional Chinese Medicine Zuojinwan in Patients with Gastric Cancer.

BACKGROUND Zuojinwan (ZJW) is a traditional Chinese prescription normally used for gastritis. Several studies indicated that it could fight against gastric cancer. This study was designed to determine the potential pharmacological mechanism of ZJW in the treatment of gastric cancer. MATERIAL AND METHODS Bioactive compounds and potential targets of ZJW and related genes of gastric cancer were retrieved from public databases. Pharmacological mechanisms including crucial ingredients, potential targets, and signaling pathways were determined using protein-protein interaction (PPI) and Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Virtual docking was performed to validate the findings. RESULTS Network analysis identified 47 active ZJW compounds, and 48 potential ZJW target genes linked to gastric cancer. Quercetin, beta-sitosterol, isorhamnetin, wogonin, and baicalein were identified as potential candidate agents. Our PPI analysis results combined with previously published results indicated that matrix metalloproteinases family members MMP9, MMP1, and MMP3 may play key roles in the anti-gastric cancer effect of ZJW. Molecular docking analysis showed that these crucial targets had good affinity for the representative components in ZJW. GO and KEGG enrichment analysis showed that ZJW target genes functioned in multiple pathways for treating gastric cancer, including interleukin-17 signaling and platinum drug resistance. CONCLUSIONS Our results illuminate the active ingredients, associated targets, biological processes, and signaling pathways of ZJW in the treatment of gastric cancer. This study enhances our understanding of the potential effects of ZJW in gastric cancer and demonstrates a feasible method for discovering potential drugs from Chinese medicinal formulas.

Effect of Chitosan as a Cross-Linker on Matrix Metalloproteinase Activity and Bond Stability with Different Adhesive Systems.

The aim of the present study was to evaluate the effect of 0.1% chitosan (Ch) solution as an additional primer on the mechanical durability and enzymatic activity on dentine using an etch-and-rinse (E&R) adhesive and a universal self-etch (SE) adhesive. Microtensile bond strength and interfacial nanoleakage expression of the bonded interfaces for all adhesives (with or without pretreatment with 0.1% Ch solution for 1 min and air-dried for 5 seconds) were analyzed immediately and after 10,000 thermocycles. Zymograms of protein extracts from human dentine powder incubated with Optibond FL and Scotchbond Universal on untreated or Ch-treated dentine were obtained to examine dentine matrix metalloproteinase (MMP) activities. The use of 0.1% Ch solution as an additional primer in conjunction with the E&R or SE adhesive did not appear to have influenced the immediate bond strength (T0) or bond strength after thermocycling (T1). Zymography showed a reduction in MMP activities only for mineralized and demineralized dentine powder after the application of Ch. Application of 0.1% Ch solution does not increase the longevity of resin-dentine bonds. Nonetheless, the procedure appears to be proficient in reducing dentine MMP activities within groups without adhesive treatments. Further studies are required to comprehend the cross-linking of Ch with dentine collagen.

Pharmacological inhibition of mTORC1 but not mTORC2 protects against human disc cellular apoptosis, senescence, and extracellular matrix catabolism through Akt and autophagy induction.

OBJECTIVE: The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that integrates nutrients to execute cell growth. We hypothesized that mTOR is influential in the intervertebral disc-largest avascular, low-nutrient organ. Our objective was to identify the optimal mTOR inhibitor for treating human degenerative disc disease. DESIGN: mTOR complex 1 (mTORC1) regulates p70/ribosomal S6 kinase (p70/S6K), negatively regulates autophagy, and is controlled by Akt. Akt is controlled by phosphatidylinositol 3-kinase (PI3K) and mTOR complex 2 (mTORC2). mTORC1 inhibitors-rapamycin, temsirolimus, everolimus, and curcumin, mTORC1&mTORC2 inhibitor-INK-128, PI3K&mTOR inhibitor-NVP-BEZ235, and Akt inhibitor-MK-2206-were applied to human disc nucleus pulposus (NP) cells. mTOR signaling, autophagy, apoptosis, senescence, and matrix metabolism were evaluated. RESULTS: mTORC1 inhibitors decreased p70/S6K but increased Akt phosphorylation, promoted autophagy with light chain 3 (LC3)-II increases and p62/sequestosome 1 (p62/SQSTM1) decreases, and suppressed pro-inflammatory interleukin-1 beta (IL-1ß)-induced apoptotic terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) positivity (versus rapamycin, 95% confidence interval (CI) -0.431 to -0.194; temsirolimus, 95% CI -0.529 to -0.292; everolimus, 95% CI -0.477 to -0.241; curcumin, 95% CI -0.248 to -0.011) and poly (ADP-ribose) polymerase (PARP) and caspase-9 cleavage, senescent senescence-associated beta-galactosidase (SA-ß-gal) positivity (versus rapamycin, 95% CI -0.437 to -0.230; temsirolimus, 95% CI -0.534 to -0.327; everolimus, 95% CI -0.485 to -0.278; curcumin, 95% CI -0.210 to -0.003) and p16/INK4A expression, and catabolic matrix metalloproteinase (MMP) release and activation. Meanwhile, dual mTOR inhibitors decreased p70/S6K and Akt phosphorylation without enhanced autophagy and suppressed apoptosis, senescence, and matrix catabolism. MK-2206 counteracted protective effects of temsirolimus. Additional disc-tissue analysis found relevance of mTOR signaling to degeneration grades. CONCLUSION: mTORC1 inhibitors-notably temsirolimus with an improved water solubility-but not dual mTOR inhibitors protect against inflammation-induced apoptosis, senescence, and matrix catabolism in human disc cells, which depends on Akt and autophagy induction.

Methotrexate an Old Drug with New Tricks.

Methotrexate (MTX) is the first line drug for the treatment of a number of rheumatic and non-rheumatic disorders. It is currently used as an anchor disease, modifying anti-rheumatic drug in the treatment of rheumatoid arthritis (RA). Despite the development of numerous new targeted therapies, MTX remains the backbone of RA therapy due to its potent efficacy and tolerability. There has been also a growing interest in the use of MTX in the treatment of chronic viral mediated arthritis. Many viruses-including old world alphaviruses, Parvovirus B19, hepatitis B/C virus, and human immunodeficiency virus-have been associated with arthritogenic diseases and reminiscent of RA. MTX may provide benefits although with the potential risk of attenuating patients' immune surveillance capacities. In this review, we describe the emerging mechanisms of action of MTX as an anti-inflammatory drug and complementing its well-established immunomodulatory activity. The mechanisms involve adenosine signaling modulation, alteration of cytokine networks, generation of reactive oxygen species and HMGB1 alarmin suppression. We also provide a comprehensive understanding of the mechanisms of MTX toxic effects. Lastly, we discussed the efficacy, as well as the safety, of MTX used in the management of viral-related rheumatic syndromes.

Quercetin Inhibits the Migration and Invasion of HCCLM3 Cells by Suppressing the Expression of p-Akt1, Matrix Metalloproteinase (MMP) MMP-2, and MMP-9.

BACKGROUND Quercetin is a natural bioactive flavonoid that is present in a wide variety of vegetables and fruits and exhibits a promising anti-metastasis property in various human cancer cells. However, the effect of quercetin on human HCCLM3 cells is unclear. MATERIAL AND METHODS In the current study, a wound-healing assay was performed using quercetin-treated HCCLM3 cells to further explore whether quercetin affects the motility of human HCCLM3 cells. Transwell assay was used to explore the potential effect of quercetin in HCCLM3 cells on cell migration and cell invasion. Western blotting analysis was used to explore the expression of p-Akt1, MMP-2, and MMP-9 in quercetin-treated HCCLM3 cells. RESULTS The wound-healing time was delayed in quercetin-treated HCCLM3 cells, and the ability to migrate and invade was inhibited in quercetin-treated human HCCLM3 cells. Moreover, the protein levels of p-Akt1, MMP-2, and MMP-9 were down-regulated in quercetin-treated HCCLM3 cells, as detected by Western blotting. CONCLUSIONS Our data show that quercetin attenuated cell migration and invasion by suppressing the protein levels of p-Akt1, MMP-2, and MMP-9 in HCCLM3 cells.

Biological wound matrices with native dermis-like collagen efficiently modulate protease activity.

OBJECTIVE: When the delicate balance between catabolic and anabolic processes is disturbed for any reason, the healing process can stall, resulting in chronic wounds. In chronic wound pathophysiology, proteolytic imbalance is implicated due to elevated protease levels mediating tissue damage. Hence, it is important to design appropriate wound treatments able to control and modulate protease activity directly at the host/biomaterial interface. Here, we investigate collagen-based wound dressings with the focus on their potential to adsorb and inactivate tissue proteases. METHOD: We examined the effect of six collagen-based dressings on their ability to adsorb and inactivate different granulocyte proteases, plasmin, human neutrophil elastase (HLE), and matrix metalloproteases (MMP)-1, -2, -8, and -9, by an integrated approach including immunoelectron microscopy. RESULTS: We observed a reduction of the proteolytic activities of plasmin, HLE, and MMP-1, -2, -8, and -9, both on the biomaterial surface and in human chronic wound fluid. The most pronounced effect was observed in collagen-based dressings, with the highest content of native collagen networks resembling dermis structures. CONCLUSION: Our data suggest that this treatment strategy might be beneficial for the chronic wound environment, with the potential to promote improved wound healing.

Evaluation of Hybrid Layer and Bonding Interface after Water Storage with and without the Usage of 2% Chlorhexidine: A Scanning Electron Microscope Study.

AIM: Restorative dentists employ different bonding systems between the resin and the dentin and other dentinal tissues to achieve the goal of micromechanical retention. Studies have shown that the bond between composite and dentin degrades over time because of the action of matrix metalloproteinases (MMPs) on collagen fibrils left unprotected by acid etching. The MMPs may be partially responsible for hybrid layer degradation. Since chlorhexidine (CHX) inhibits MMPs, we hypothesized that CHX would decelerate the loss of resin-dentin bonds. Hence, this in vitro study is intended to evaluate the effects of 2% CHX on hybrid layer and bonding interface. MATERIALS AND METHODS: Totally, 40 freshly extracted molars were randomly divided into four experimental groups. In all 40 specimens, class II cavities were prepared to a depth of 1 mm below the dentinoenamel junction with no axial wall, but the elimination of the proximal enamel ridge. The teeth were then randomly divided into four experimental groups, i.e., All Bond 2 without 2% CHX (group I), All Bond 2 with 2% CHX (group II), One Coat 7.0 without 2% CHX (group III), and One Coat 7.0 with 2% CHX (group IV). All the specimens were derooted and sectioned mesiodistally into two halves and placed under water at 37°C for 3 months and observed under scanning electron microscope for the hybrid layer and resin tag formation. RESULTS: Groups I and II showed statistically significant difference when the presence/absence of resin tags was compared. When groups III and IV were compared for the presence/absence of hybrid layer and resin tags, the results were statistically significant. CONCLUSION: Between all the four experimental groups, irrespective of the bonding systems used, we concluded that groups with 2% CHX usage showed promising results with presence/ absence of hybrid layer and resin tags formation. CLINICAL SIGNIFICANCE: Studies suggest that the bond between composite and dentin degrades over time because of the action of MMPs on collagen fibrils left unprotected by acid etching. Measures should be taken to prevent this from happening and thus allow bond between composite and dentin last longer.

Discovery of a Potent Inhibitor Class with High Selectivity toward Clostridial Collagenases.

Secreted virulence factors like bacterial collagenases are conceptually attractive targets for fighting microbial infections. However, previous attempts to develop potent compounds against these metalloproteases failed to achieve selectivity against human matrix metalloproteinases (MMPs). Using a surface plasmon resonance-based screening complemented with enzyme inhibition assays, we discovered an N-aryl mercaptoacetamide-based inhibitor scaffold that showed sub-micromolar affinities toward collagenase H (ColH) from the human pathogen Clostridium histolyticum. Moreover, these inhibitors also efficiently blocked the homologous bacterial collagenases, ColG from C. histolyticum, ColT from C. tetani, and ColQ1 from the Bacillus cereus strain Q1, while showing negligible activity toward human MMPs-1, -2, -3, -7, -8, and -14. The most active compound displayed a more than 1000-fold selectivity over human MMPs. This selectivity can be rationalized by the crystal structure of ColH with this compound, revealing a distinct non-primed binding mode to the active site. The non-primed binding mode presented here paves the way for the development of selective broad-spectrum bacterial collagenase inhibitors with potential therapeutic application in humans.

Intravitreal bevacizumab alters type IV collagenases and exacerbates arrested alveologenesis in the neonatal rat lungs.

Purpose/Aim: Intravitreal bevacizumab (Avastin) is an irreversible vascular endothelial growth factor (VEGF) inhibitor used off-label to treat severe retinopathy of prematurity in extremely low gestational age neonates. VEGF and matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs) participate in lung maturation. We tested the hypothesis that intravitreal bevacizumab enters the systemic circulation and has long-lasting effects on lung MMPs. MATERIALS AND METHODS: Neonatal rats were exposed to: (1) hyperoxia (50% O2); (2) intermittent hypoxia (IH) (50% O2 with brief episodes of 12% O2); or (3) room air (RA) from birth (P0) to P14. At P14, the time of eye opening in rats, a single dose of Avastin (0.125 mg) was injected into the vitreous cavity of the left eye. A control group received equivalent volume saline. At P23 and P45, lung MMP-2 and MMP-9, and TIMP-1, and TIMP-2 were assessed in the lungs. RESULTS: At P23, Avastin increased MMP-2, MMP-9, and TIMP-1 levels in the hyperoxia group but decreased TIMP-1 levels in the IH group. The ratios of MMP-2/TIMP-1 and MMP-9/TIMP-1 were significantly elevated at P23 in the IH group treated with Avastin. At P45, the levels of MMP-2 and MMP-9 remained elevated in the hyperoxia and IH groups treated with Avastin, while a rebound increase in TIMP-1 levels was noted in the IH group. CONCLUSIONS: Avastin treatment in IH has lasting alterations in the balance between MMPs and their tissue inhibitors. These changes may lead to impaired alveologenesis and tissue damage consistent with bronchopulmonary dysplasia/chronic lung disease.

Dual targeting of cancer-related human matrix metalloproteinases and carbonic anhydrases by chiral N-(biarylsulfonyl)-phosphonic acids.

A series of nanomolar phosphonate matrix metalloproteinase (MPP) inhibitors was tested for inhibitory activity against a panel of selected human carbonic anhydrase (CA, EC 4.2.1.1) isozymes, covering the cancer-associated CA IX and XII. None of the reported sulfonyl and sulfonylamino-derivatives sensitively affected the catalytic activity of the cytosolic isoforms CA I and II, which are considered off-target isoforms in view of their physiological role. The most active inhibitors were in the series of chiral N-(sulfonyl)phosphovaline derivatives, which showed good to excellent inhibitory activity over target CAs, with compound 15 presenting the best isoform-selectivity toward CA IX. We suggest here that the phosphonates have the potential as dual inhibitors of MMPs and CAs, both involved in tumor formation, invasion and metastasis.

Sinulariolide Suppresses Cell Migration and Invasion by Inhibiting Matrix Metalloproteinase-2/-9 and Urokinase through the PI3K/AKT/mTOR Signaling Pathway in Human Bladder Cancer Cells.

Sinulariolide is a natural product extracted from the cultured-type soft coral Sinularia flexibilis, and possesses bioactivity against the movement of several types of cancer cells. However, the molecular pathway behind its effects on human bladder cancer remain poorly understood. Using a human bladder cancer cell line as an in vitro model, this study investigated the underlying mechanism of sinulariolide against cell migration/invasion in TSGH-8301 cells. We found that sinulariolide inhibited TSGH-8301 cell migration/invasion, and the effect was concentration-dependent. Furthermore, the protein expressions of matrix metalloproteinases (MMPs) MMP-2 and MMP-9, as well as urokinase, were significantly decreased after 24-h sinulariolide treatment. Meanwhile, the increased expression of tissue inhibitors of metalloproteinases (TIMPs) TIMP-1 and TIMP-2 were in parallel with an increased concentration of sinulariolide. Finally, the expressions of several key phosphorylated proteins in the mTOR signaling pathway were also downregulated by sinulariolide treatment. Our results demonstrated that sinulariolide has significant effects against TSGH-8301 cell migration/invasion, and its effects were associated with decreased levels of MMP-2/-9 and urokinase expression, as well as increased TIMP-1/TIMP-2 expression. The inhibitory effects were mediated by reducing phosphorylation proteins of the PI3K, AKT, and mTOR signaling pathway. The findings suggested that sinulariolide is a good candidate for advanced investigation with the aim of developing a new drug for the treatment of human bladder cancer.

Norepinephrine modulates osteoarthritic chondrocyte metabolism and inflammatory responses.

OBJECTIVE: Norepinephrine (NE) was measured in synovial fluid of trauma patients and sympathetic nerve fibers were detected in healthy and osteoarthritic (OA) joint tissues indicating that cartilage pathophysiology might be influenced by sympathetic neurotransmitters. The aim of this study was to elucidate the mostly unknown role of NE in OA chondrocyte metabolism and inflammatory responses. METHODS: Articular cartilage was received after total knee replacement surgery from OA patients. Expression of adrenergic receptors (AR) and tyrosine hydroxylase (TH) was tested with end point polymerase chain reaction (PCR) and immunohistochemistry. 3-dimensional (3D) cell cultures were employed to analyze effects of NE on chondrocyte cell metabolism and the expression of interleukins (ILs), matrix metalloproteases (MMPs), tissue inhibitor of metalloproteases (TIMPs), glycosaminoglycan (GAG) and collagen II under non- and inflammatory conditions. Chondrocyte monolayer cultures were used to specify AR subtypes, to analyze cell cycle distribution and to determine catecholamines in cell culture supernatants. RESULTS: AR subtypes and TH were detected in chondrocytes, whereas NE was not released in measurable amounts. 10(-6) M NE reversed IL-1ß induced changes in IL-8, MMP-13, GAG and collagen II expression/production indicating for ß-AR signaling. Additionally, NE caused cell cycle slow down and decreased proliferation via ß-AR signaling. 10(-8) M NE increased the number of proliferating cells and induced apoptosis via α1-AR signaling. CONCLUSIONS: NE affects chondrocytes from OA cartilage regarding inflammatory response and its cell metabolism in a dose dependent manner. The sympathetic nervous system (SNS) may have a dual function in OA pathology with preserving a stable chondrocyte phenotype via ß-AR signaling and OA pathogenesis accelerating effects via α-AR signaling.

Protective Effects and Mechanisms of Salvianolic Acid B Against H2O2-Induced Injury in Induced Pluripotent Stem Cell-Derived Neural Stem Cells.

Induced pluripotent stem cells (iPSCs) have the potential to differentiate into neural lineages. Salvianolic acid B (Sal B) is a commonly used, traditional Chinese medicine for enhancing neuroprotective effects, and has antioxidant, anti-inflammatory, and antiapoptotic properties. Here, we explore the potential mechanism of Sal B in protecting iPSC-derived neural stem cells (NSCs) against H2O2-induced injury. iPSCs were induced into NSCs, iPSC-derived NSCs were treated with 50 µM Sal B for 24.5 h and 500 µM H2O2 for 24 h. The resulting effects were examined by flow cytometry analysis, quantitative reverse-transcription polymerase chain reaction, and western blotting. Upon H2O2 exposure, Sal B significantly promoted cell viability and stabilization of the mitochondrial membrane potential. Sal B also visibly decreased the cell apoptotic ratio. In addition, Sal B markedly reduced expression of matrix metalloproteinase (MMP)-2 and -9, and phosphospecific signal transducer and activator of transcription 3 (p-STAT3), and increased the level of tissue inhibitor of metalloproteinase (TIMP)-2 in iPSC-derived NSCs induced by H2O2. These results suggest that Sal B protects iPSC-derived NSCs against H2O2-induced oxidative stress. The mechanisms of this stress tolerance may be attributed to modulation of the MMP/TIMP system and inhibition of the STAT3 signaling pathway.

Anthocyanins from black rice (Oryza sativa L.) demonstrate antimetastatic properties by reducing MMPs and NF-κB expressions in human oral cancer CAL 27 cells.

Aside from the commonly known white rice lines, colored varieties also exist. These varieties have historically been used in Chinese medicine. Anthocyanins, a large group of natural polyphenols existing in a variety of daily fruits and vegetables, have been widely recognized as cancer chemopreventive agents. The primary objective of cancer treatment strategies has traditionally focused on preventing the occurrence of metastasis. In this research the antimetastatic mechanism of anthocyanins on the invasion/migration of human oral CAL 27 cells was performed using a transwell to quantify the migratory potential of CAL 27 cells and the results show that anthocyanins can inhibit the in vitro migration and invasion of CAL 27 cancer cells. In addition, the gelatin zymography assay indicated that anthocyanins inhibited the activity of matrix metalloproteinases-2 (MMP-2). Western blotting assay also demonstrated that anthocyanins inhibited the associated protein expression of migration/invasion of CAL 27 cell. Immunofluorescence staining proved that anthocyanins inhibited nuclear factor kappa B p65 (NF-κB p65) expressions. These results demonstrated that anthocyanins from a species of black rice (selected purple glutinous indica rice cultivated at Asia University) could suppress CAL 27 cell metastasis by reduction of MMP-2, MMP-9, and NF-κB p65 expression through the suppression of PI3K/Akt pathway and inhibition of NF-κB levels.

Tuberculosis, pulmonary cavitation, and matrix metalloproteinases.

Tuberculosis (TB), a chronic infectious disease of global importance, is facing the emergence of drug-resistant strains with few new drugs to treat the infection. Pulmonary cavitation, the hallmark of established disease, is associated with very high bacillary burden. Cavitation may lead to delayed sputum culture conversion, emergence of drug resistance, and transmission of the infection. The host immunological reaction to Mycobacterium tuberculosis is implicated in driving the development of TB cavities. TB is characterized by a matrix-degrading phenotype in which the activity of proteolytic matrix metalloproteinases (MMPs) is relatively unopposed by the specific tissue inhibitors of metalloproteinases. Proteases, in particular MMPs, secreted from monocyte-derived cells, neutrophils, and stromal cells, are involved in both cell recruitment and tissue damage and may cause cavitation. MMP activity is augmented by proinflammatory chemokines and cytokines, is tightly regulated by complex signaling paths, and causes matrix destruction. MMP concentrations are elevated in human TB and are closely associated with clinical and radiological markers of lung tissue destruction. Immunomodulatory therapies targeting MMPs in preclinical and clinical trials are potential adjuncts to TB treatment. Strategies targeting patients with cavitary TB have the potential to improve cure rates and reduce disease transmission.

Structural activity relationship analysis (SAR) and in vitro testing reveal the anti-ageing potential activity of acetyl aspartic acid.

BACKGROUND: Acetyl aspartic acid (A-A-A) was discovered through gene array analysis with corresponding connectivity mapping (Cmap), aiming for identification of new compounds with anti-ageing properties. OBJECTIVE: The aim of this study was to use structural activity relationship (SAR) analysis to identify a predictive mechanism of action of A-A-A. The findings from SAR will be further characterized by in vitro activity testing. Furthermore, we aimed to investigate the role of polymerized filamentous F-actin in ageing fibroblasts and to evaluate the effect of A-A-A on this model. METHODS: To predict the mode of action of A-A-A, we used the PASS computer program as a SAR model. In vitro, scratch motility tests with immortalized keratinocytes were used as a model for wound healing potential. Matrix metalloproteinase 1-3 (MMP 1-3) was analysed using multiplex protein assays (Luminex), and polymerized actin was detected by phalloidin staining in dermal fibroblasts (HDF). RESULTS: SAR analysis predicted that A-A-A would possess both epidermal and dermal activities with identification of wound healing and MMP inhibition potential. Further in vitro studies confirmed the wound healing potential using keratinocyte scratch motility assays. We were also able to confirm the dermal activities predicted by inhibition of MMP (MMP 1-3) in HDF by A-A-A. In addition, we found a positive relationship between age and F-actin expression. We also discovered that stimulation of HDF with A-A-A for 72 h significantly reduced the polymerized cytoskeletal network as visualized by inhibition of F-actin expression. In fact, A-A-A leveraged the expression of F-actin in middle-aged female fibroblasts (50 years of age) to the level of young female fibroblasts (30 years of age), corresponding to a 40% reduction in F-actin expression. CONCLUSION: Using an in silico and in vitro approach, we were able to demonstrate that A-A-A has the capacity to target different compartments of the skin through keratinocyte regeneration, MMP inhibition and relief in fibroblasts stiffness by reduction of F-actin cytoskeletal network in HDF.

[The influence of antihypertensive treatment on arterial stiffness, shear stress and activity of chosen matrix metalloproteinases]. / Wplyw 1ecenia przeciwnadcisnieniowego na sztywnosc tetnic, stres scinajacy i aktywnosc wybranych metaloproteinaz macierzy zewnatrzkomórkowej.

UNLABELLED: The aim of the study was to compare therapeutic effects of chosen antihypertensive drugs on arterial stiffness, shear stress in carotid arteries and metalloproteinases activity, moreover analysis of relationship of these variables in the course of treatment. METHODS: 95 patients with essential arterial hypertension stage 1 or 2 were randomized to 6 months monotherapy with: quinapril, amlodipine, hydrochlorothiazide, losartan or bisoprolol. Each therapeutic group consisted of 19 patients (N=19). Before and then after 1, 3 and 6 months of treatment carotid-femoral pulse wave velocity (PWV) by using a Complior device, ultrasound of carotid arteries were performed. Blood samples for the measurement of whole blood viscosity were taken during each visit. Shear stress (SS) was calculated using measured variables: blood viscosity and velocity of blood flow. Serum concentration of metalloproteinase 3 (MMP-3) and plasma concentration of tissue inhibitor of metalloproteinase I (TIMP-1) were measured at the initial visit and after 6 months of treatment. RESULTS: ANOVA for repeated measurements revealed for all groups significant decrease of PWV (ΔPWV) and MMP-3 (ΔMMP-3) concentration and increase of shear stress in carotid artery and TIMP-1 (ΔTIMP-1) concentration (p<0.05). No between groups differences appeared in above effects (p>0.05). The multiple regression analysis for the change of PWV (ΔPWV) in the study group considering all investigated variables at R2 = 0,27 revealed its significant relation to PWV at first visit, ΔTIMP-1, ΔMMP-3 and Δ shear stress counted for the maximum flow velocity in common carotid artery. Conclusion: Irrespectively of chosen drug we observed similar effect for PWV drop. Reduction of arterial stiffness as a result of antihypertensive therapy is strongly connected with shear stress increase that is secondary to blood flow velocity growth and changes in connective tissue metabolism.