In vitro multitarget activity of sulfadiazine substituted triazenes as antimicrobial, cytotoxic, and larvicidal agents.

Multidrug resistance (MDR) causes difficulties in the treatment of infections and cancer. Research and development studies have become increasingly important for the strategy of preventing MDR. There is a need for new multitarget drug research and advancement to reduce the development of drug resistance in drug-drug interactions and reduce cost and toxic effects. This study aimed to determine the effects of multi-target triazene compounds on antibacterial, antifungal, antiviral, cytotoxic, and larvicidal activities were investigated in vitro. A series of 12 novel of 1,3-diaryltriazene-substituted sulfadiazine (SDZ) derivatives were synthesized, and the obtained pure products characterized in detail by spectroscopic and analytic methods (FT-IR, 1 H-NMR, 13 C-NMR, and melting points). The antibacterial and antifungal activities of these derivatives (AH1-12) were determined by broth microdilution method. All derivatives have been evaluated in cell-based assays for cytotoxic and antiviral activities against Modified Vaccinia Virus Ankara. The larvicidal efficacy of these chemical compounds was also investigated by using Lucilia sericata (L. sericata) larvae. Twelve 1,3-diaryltriazene-substituted SDZ derivatives (AH1-12) were designed and developed as potent multitargeted compounds. Among them, the AH1 derivative showed the most antibacterial and antifungal activity. Besides, synthesized derivatives AH2, AH3, AH5, and AH7 showed higher antiviral activity than SDZ. All synthesized derivatives showed higher cytotoxic activity than SDZ. Also, they showed larvicidal activity at 72 h of the experiment. As a result, these compounds might be great leads for the development of next-generation multitargeted agents.

Diaryl triazenes inhibit cytochrome P450 1A1 and 1B1 more strongly than aryl morpholino triazenes.

Several diaryl triazene derivatives were synthesized and tested for their ability to inhibit cytochrome P450 1A1 and 1B1 as a potential means to prevent and treat cancer. These compounds are more planar than their conformational flexible aryl morpholino triazene counterparts that were previously shown to inhibit the above enzymes. As a result, the diaryl triazenes are more likely to exhibit increased binding to the enzyme active sites and inhibit these enzymes more strongly than the aryl morpholino triazenes. The data indicates that the diaryl triazenes inhibit cytochrome P450 1A1 and 1B1 one to two orders of magnitude more strongly than the aryl morpholino triazenes. Furthermore, compounds 8-10 strongly inhibited cytochrome P450 1B1 with IC50 values of 51 nM, 740 nM, and 590 nM respectively. Thus, diaryl triazenes should be further investigated as a potential chemopreventive agent.

Short Chain Fatty Acid Acetate Increases TNFα-Induced MCP-1 Production in Monocytic Cells via ACSL1/MAPK/NF-κB Axis.

Short-chain fatty acid (SCFA) acetate, a byproduct of dietary fiber metabolism by gut bacteria, has multiple immunomodulatory functions. The anti-inflammatory role of acetate is well documented; however, its effect on monocyte chemoattractant protein-1 (MCP-1) production is unknown. Similarly, the comparative effect of SCFA on MCP-1 expression in monocytes and macrophages remains unclear. We investigated whether acetate modulates TNFα-mediated MCP-1/CCL2 production in monocytes/macrophages and, if so, by which mechanism(s). Monocytic cells were exposed to acetate with/without TNFα for 24 h, and MCP-1 expression was measured. Monocytes treated with acetate in combination with TNFα resulted in significantly greater MCP-1 production compared to TNFα treatment alone, indicating a synergistic effect. On the contrary, treatment with acetate in combination with TNFα suppressed MCP-1 production in macrophages. The synergistic upregulation of MCP-1 was mediated through the activation of long-chain fatty acyl-CoA synthetase 1 (ACSL1). However, the inhibition of other bioactive lipid enzymes [carnitine palmitoyltransferase I (CPT I) or serine palmitoyltransferase (SPT)] did not affect this synergy. Moreover, MCP-1 expression was significantly reduced by the inhibition of p38 MAPK, ERK1/2, and NF-κB signaling. The inhibition of ACSL1 attenuated the acetate/TNFα-mediated phosphorylation of p38 MAPK, ERK1/2, and NF-κB. Increased NF-κB/AP-1 activity, resulting from acetate/TNFα co-stimulation, was decreased by ACSL1 inhibition. In conclusion, this study demonstrates the proinflammatory effects of acetate on TNF-α-mediated MCP-1 production via the ACSL1/MAPK/NF-κB axis in monocytic cells, while a paradoxical effect was observed in THP-1-derived macrophages.

Enhanced lipid metabolism induces the sensitivity of dormant cancer cells to 5-aminolevulinic acid-based photodynamic therapy.

Cancer can develop into a recurrent metastatic disease with latency periods of years to decades. Dormant cancer cells, which represent a major cause of recurrent cancer, are relatively insensitive to most chemotherapeutic drugs and radiation. We previously demonstrated that cancer cells exhibited dormancy in a cell density-dependent manner. Dormant cancer cells exhibited increased porphyrin metabolism and sensitivity to 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT). However, the metabolic changes in dormant cancer cells or the factors that enhance porphyrin metabolism have not been fully clarified. In this study, we revealed that lipid metabolism was increased in dormant cancer cells, leading to ALA-PDT sensitivity. We performed microarray analysis in non-dormant and dormant cancer cells and revealed that lipid metabolism was remarkably enhanced in dormant cancer cells. In addition, triacsin C, a potent inhibitor of acyl-CoA synthetases (ACSs), reduced protoporphyrin IX (PpIX) accumulation and decreased ALA-PDT sensitivity. We demonstrated that lipid metabolism including ACS expression was positively associated with PpIX accumulation. This research suggested that the enhancement of lipid metabolism in cancer cells induces PpIX accumulation and ALA-PDT sensitivity.

Assessment of the biological potential of diaryltriazene-derived triazene compounds.

In the present study, novel, 1,3-diaryltriazene-derived triazene compounds were synthesized and tested. Triazenes are versatile and belong to a group of alkylating agents with interesting physicochemical properties and proven biological activities. This study describes the synthesis, molecular and crystalline structure, biological activity evaluation, and antifungal and antimicrobial potentials of 1,3-bis(X-methoxy-Y-nitrophenyl)triazenes [X = 2 and 5; Y = 4 and 5]. The antimicrobial and antifungal activities of the compounds were tested by evaluating the sensitivity of bacteria (American Type Culture Collection, ATCC) and clinical isolates to their solutions using standardized microbiological assays, cytotoxicity evaluation, and ecotoxicity tests. The antimicrobial potentials of triazenes were determined according to their minimum inhibitory concentrations (MICs); these compounds were active against gram-positive and gram-negative bacteria, with low MIC values. The most surprising result was obtained for T3 having the effective MIC of 9.937 µg/mL and antifungal activity against Candida albicans ATCC 90028, C. parapsilosis ATCC 22019, and C. tropicallis IC. To the best of our knowledge, this study is the first to report promising activities of triazene compounds against yeast and filamentous fungi. The results showed the potential utility of triazenes as agents affecting selected resistant bacterial and fungal strains.

Antibacterial Therapy by Ag+ Ions Complexed with Titan Yellow/Congo Red and Albumin during Anticancer Therapy of Urinary Bladder Cancer.

According to the World Health Organization report, the increasing antibiotic resistance of microorganisms is one of the biggest global health problems. The percentage of bacterial strains showing multidrug resistance (MDR) to commonly used antibiotics is growing rapidly. Therefore, the search for alternative solutions to antibiotic therapy has become critical to combat this phenomenon. It is especially important as frequent and recurring infections can cause cancer. One example of this phenomenon is urinary tract infections that can contribute to the development of human urinary bladder carcinoma. This tumor is one of the most common malignant neoplasms in humans. It occurs almost three times more often in men than in women, and in terms of the number of cases, it is the fifth malignant neoplasm after prostate, lung, colon, and stomach cancer. The risk of developing the disease increases with age. Despite the improvement of its treatment methods, the current outcome in the advanced stages of this tumor is not satisfactory. Hence, there is an urgent need to introduce innovative solutions that will prove effective even in the advanced stage of the disease. In our study, a nanosystem based on ionic silver (Ag+) bound to a carrier-Titan yellow (TY) was analyzed. The possibility of binding the thus formed TY-Ag system to Congo red (CR) and albumin (BSA) was determined. TY-Ag binding to CR provides for better nanosystem solubility and enables its targeted intracellular transport and binding to immune complexes. The binding of TY-Ag or CR-TY-Ag to albumin also protects the system against the uncontrolled release of silver ions. It will also allow the delivery of silver in a targeted manner directly to the desired site in the case of intravenous administration of such a system. In this study, the MIC (Minimum Inhibitory Concentration) and MBC (Minimum Bactericidal Concentration) values of the TY-Ag or BSA-TY-Ag systems were determined in two reference strains (Escherichia coli and Staphylococcus aureus). The paper presents nanosystems with a size of about 40-50 nm, with an intense antibacterial effect obtained at concentrations of 0.019 mM. We have also discovered that TY-Ag free or complexed with BSA (with a minimal Ag+ dose of 15-20 µM) inhibited cancer cells proliferation. TY-Ag complex diminished migration and effectively inhibited the T24 cell viability and induced apoptosis. On the basis of the obtained results, it has been shown that the presented systems may have anti-inflammatory and antitumor properties at the same time. TY-Ag or BSA-TY-Ag are new potential drugs and may become in future important therapeutic compounds in human urinary bladder carcinoma treatment and/or potent antimicrobial factors as an alternative to antibiotics.

Synthesis and in silico studies of triazene-substituted sulfamerazine derivatives as acetylcholinesterase and carbonic anhydrases inhibitors.

A novel series of sulfonamides, 4-(3-phenyltriaz-1-en-1-yl)-N-(4-methyl-2-pyrimidinyl)benzenesulfonamides (1-9), was designed and synthesized by the diazo reaction between sulfamerazine and substituted aromatic amines for the first time. Their chemical structures were characterized by 1 H nuclear magnetic resonance (NMR), 13 C NMR, and high-resolution mass spectra. The newly synthesized compounds were evaluated in terms of acetylcholineasterase (AChE) and human carbonic anhydrases (hCA) I and II isoenzymes inhibitory activities. According to the AChE inhibition results, the Ki values of the compounds 1-9 were in the range of 19.9 ± 1.5 to 96.5 ± 20.7 nM against AChE. Tacrine was used as the reference drug and its Ki value was 49.2 ± 2.7 nM against AChE. The Ki values of the compounds 1-9 were in the range of 10.2 ± 2.6 to 101.4 ± 27.8 nM against hCA I, whereas they were 18.3 ± 4.4 to 48.1 ± 4.5 nM against hCA II. Acetazolamide was used as a reference drug and its Ki values were 72.2 ± 5.4 and 52.2 ± 5.7 nM against hCA I and hCA II, respectively. The most active compounds, 1 (nonsubstituted) against AChE, 5 (4-ethoxy-substituted) against hCA I, and 8 (4-bromo-substituted) against hCA II, were chosen and docked at the binding sites of these enzymes to explain the inhibitory activities of the series. The newly synthesized compounds presented satisfactory pharmacokinetic properties via the estimation of ADME properties.

Proof-of-Concept Study of the NOTI Chelating Platform: Preclinical Evaluation of 64Cu-Labeled Mono- and Trimeric c(RGDfK) Conjugates.

PURPOSE: We recently developed a chelating platform based on the macrocycle 1,4,7-triazacyclononane with up to three five-membered azaheterocyclic arms for the preparation of 68Ga- and 64Cu-based radiopharmaceuticals. Based on this platform, the chelator scaffold NOTI-TVA with three additional carboxylic acid groups for bioconjugation was synthesized and characterized. The primary aims of this proof-of-concept study were (1) to evaluate if trimeric radiotracers on the basis of the NOTI-TVA 6 scaffold can be developed, (2) to determine if the additional substituents for bioconjugation at the non-coordinating NH atoms of the imidazole residues of the building block NOTI influence the metal binding properties, and (3) what influence multiple targeting vectors have on the biological performance of the radiotracer. The cyclic RGDfK peptide that specifically binds to the αvß3 integrin receptor was selected as the biological model system. PROCEDURES: Two different synthetic routes for the preparation of NOTI-TVA 6 were explored. Three c(RGDfK) peptide residues were conjugated to the NOTI-TVA 6 building block by standard peptide chemistry providing the trimeric bioconjugate NOTI-TVA-c(RGDfK)3 9. Labeling of 9 with [64Cu]CuCl2 was performed manually at pH 8.2 at ambient temperature. Binding affinities of Cu-8, the Cu2+ complex of the previously described monomer NODIA-Me-c(RGDfK) 8, and the trimer Cu-9 to integrin αvß3 were determined in competitive cell binding experiments in the U-87MG cell line. The pharmacokinetics of both 64Cu-labeled conjugates [64Cu]Cu-8 and [64Cu]Cu-9 were determined by small-animal PET imaging and ex vivo biodistribution studies in mice bearing U-87MG xenografts. RESULTS: Depending on the synthetic route, NOTI-TVA 6 was obtained with an overall yield up to 58 %. The bioconjugate 9 was prepared in 41 % yield. Both conjugates [64Cu]Cu-8 and [64Cu]Cu-9 were radiolabeled quantitatively at ambient temperature in high molar activities of Am ~ 20 MBq nmol-1 in less than 5 min. Competitive inhibitory constants IC50 of c(RDGfK) 7, Cu-8, and Cu-9 were determined to be 159.5 ± 1.3 nM, 256.1 ± 2.1 nM, and 99.5 ± 1.1 nM, respectively. In small-animal experiments, both radiotracers specifically delineated αvß3 integrin-positive U-87MG tumors with low uptake in non-target organs and rapid blood clearance. The trimer [64Cu]Cu-9 showed a ~ 2.5-fold higher tumor uptake compared with the monomer [64Cu]Cu-8. CONCLUSIONS: Functionalization of NOTI at the non-coordinating NH atoms of the imidazole residues for bioconjugation was straightforward and allowed the preparation of a homotrimeric RGD conjugate. After optimization of the synthesis, required building blocks to make NOTI-TVA 6 are now available on multi-gram scale. Modifications at the imidazole groups had no measurable impact on metal binding properties in vitro and in vivo suggesting that the NOTI scaffold is a promising candidate for the development of 64Cu-labeled multimeric/multifunctional radiotracers.

Co-culture hydrogel micro-chamber array-based plate for anti-tumor drug development at single-element resolution.

In response to the need for reliable cellular models that reflect complex tumor microenvironmental properties, and enable more precise testing of anti-cancer therapeutics effects on humans, a co-culture platform for in-vitro model that enhances the physiology of breast cancer (BC) microenvironment is presented. A six well imaging plate wherein each macro-well contains several separate compartments was designed. Three-dimensional (3D) cancer spheroids are generated and cultured in the inner compartment which is embossed with an array of nano-liter micro-chambers made of hydrogel. Stromal cells are cultured in the outer chambers. The two cell types are cultured side-by-side, sharing a common space, thus enabling extra-cellular communication via secreted molecules. As proof of concept, a model of BC tumor microenvironment was recapitulated by co-cultivating 3D MCF7 spheroids in the presence of tumor-associated macrophages (TAMs). The presence of TAMs induced an aggressive phenotype by promoting spheroid growth, enhancing survivin expression levels and enabling invasive behavior. Moreover, TAMs influenced the response of BC spheroids to cytotoxic treatment as well as hormonal drug therapy, and enhanced the effects of nitric oxide donor. The platform enables time-lapse imaging and treatment without losing spatial location of the measured spheroids, thereby allowing measurements and analysis at individual-object resolution in an easy and efficient manner.

Expedient synthesis and anticancer evaluation of dual-action 9-anilinoacridine methyl triazene chimeras.

The efficient synthesis of molecular hybrids including a DNA-intercalating 9-anilinoacridine (9-AnA) core and a methyl triazene DNA-methylating moiety is described. Nucleophilic aromatic substitution (SN Ar) and electrophilic aromatic substitution (EAS) reactions using readily accessible starting materials provide a quick entry to novel bifunctional anticancer molecules. The chimeras were evaluated for their anticancer activity. Chimera 7b presented the highest antitumor activity at low micromolar IC50 values in antiproliferative assays performed with various cancer cell lines. In comparison, compound 7b outperformed DNA-intercalating drugs like amsacrine and AHMA. Mechanistic studies of chimera 7b suggest a dual mechanism of action: methylation of the DNA-repairing protein MGMT associated with the triazene structural portion and Topo II inhibition by intercalation of the acridine core.

SR-BI mediates neutral lipid sorting from LDL to lipid droplets and facilitates their formation.

SR-BI binds various lipoproteins, including HDL, LDL as well as VLDL, and mediates selective cholesteryl ester (CE) uptake. HDL derived CE accumulates in cellular lipid droplets (LDs), which also store triacylglycerol (TAG). We hypothesized that SR-BI could significantly facilitate LD formation, in part, by directly transporting LDL derived neutral lipids (NL) such as CE and TAG into LDs without lipolysis and de novo lipid synthesis. SR-BI overexpression greatly increased LDL uptake and LD formation in stably transfected HeLa cells (SR-BI-HeLa). LDs isolated from SR-BI-HeLa contained 4- and 7-times more CE and TAG, respectively, than mock-transfected HeLa (Mock-HeLa). In contrast, LDL receptor overexpression in HeLa (LDLr-HeLa) greatly increased LDL uptake, degradation with moderate 1.5- and 2-fold increases of CE and TAG, respectively. Utilizing CE and TAG analogs, BODIPY-TAG (BP-TAG) and BODIPY-CE (BP-CE), for tracking LDL NL, we found that after initial binding of LDL to SR-BI-HeLa, apoB remained at the cell surface, while BP-CE and BP-TAG were sorted and simultaneously transported together to LDs. Both lipids demonstrated limited internalization to lysosomes or endoplasmic reticulum in SR-BI-HeLa. In LDLr-HeLa, NLs demonstrated clear lysosomal sequestration without their sorting to LDs. An inhibition of TAG and CE de novo synthesis by 90-95% only reduced TAG and CE LD content by 45-50%, and had little effect on BP-CE and BP-TAG transport to LDs in SR-BI HeLa. Furthermore, intravenous infusion of 1-2 mg of LDL increased liver LDs in normal (WT) but not in SR-BI KO mice. Mice transgenic for human SR-BI demonstrated higher liver LD accumulation than WT mice. Finally, Electro Spray Infusion Mass Spectrometry (ESI-MS) using deuterated d-CE found that LDs accumulated up to 40% of unmodified d-CE LDL. We conclude that SR-BI mediates LDL-induced LD formation in vitro and in vivo. In addition to cytosolic NL hydrolysis and de novo lipid synthesis, this process includes selective sorting and transport of LDL NL to LDs with limited lysosomal NL sequestration and the transport of LDL CE, and TAG directly to LDs independently of de novo synthesis.

The effect of the triazene compound CT913 on ovarian cancer cells in vitro and its synergistic interaction with the PARP-inhibitor olaparib.

OBJECTIVES: Extending the therapeutic spectrum of PARP-inhibitors (PARPi) beyond BRCA1-deficiency and/or overcoming PARPi-resistance is of high clinical interest. This is particularly true for the identification of innovative therapeutic strategies for ovarian cancer, given the recent advances in the use of PARPi in clinical practice. In this regard, the combination of PARPi with chemotherapy is a possible strategy for defining new therapeutic standards. In this study, we analyzed the therapeutic effect of novel triazene derivatives, including the drug CT913 and its metabolite CT913-M1 on ovarian cancer cells and describe their interaction with the PARPi olaparib. METHODS: In vitro assays for drug characterization including RNA-Seq were applied in a selected panel of ovarian cancer cell lines. RESULTS: CT913 treatment conferred a dose-dependent reduction of cell viability in a set of platinum-sensitive and platinum-resistant ovarian cancer cell lines with an IC50 in the higher micromolar range (553-1083 µM), whereas its metabolite CT913-M1 was up to 69-fold more potent, especially among long-term treatment (IC50 range: 8-138 µM). Neither of the drugs sensitized for cisplatin. CT913 conferred synthetic lethality in BRCA1-deficient ovarian cancer cells, indicating that its effect is augmented by a deficiency in homologous recombination repair (HR). Furthermore, CT913 showed a synergistic interaction with olaparib, independently of BRCA1 mutational status. CT913 strongly induced CDKN1A transcription, suggesting cell cycle arrest as an early response to this drug. It moreover downregulated a variety of transcripts involved in DNA-repair pathways. CONCLUSIONS: This is the first study, suggesting the novel triazene drug CT913 as enhancer drug for extending the therapeutic spectrum of PARPi.

Long-chain acyl-CoA synthetase-1 mediates the palmitic acid-induced inflammatory response in human aortic endothelial cells.

Saturated fatty acid (SFA) induces proinflammatory response through a Toll-like receptor (TLR)-mediated mechanism, which is associated with cardiometabolic diseases such as obesity, insulin resistance, and endothelial dysfunction. Consistent with this notion, TLR2 or TLR4 knockout mice are protected from obesity-induced proinflammatory response and endothelial dysfunction. Although SFA causes endothelial dysfunction through TLR-mediated signaling pathways, the mechanisms underlying SFA-stimulated inflammatory response are not completely understood. To understand the proinflammatory response in vascular endothelial cells in high-lipid conditions, we compared the proinflammatory responses stimulated by palmitic acid (PA) and other canonical TLR agonists [lipopolysaccharide (LPS), Pam3-Cys-Ser-Lys4 (Pam3CSK4), or macrophage-activating lipopeptide-2)] in human aortic endothelial cells. The expression profiles of E-selectin and the signal transduction pathways stimulated by PA were distinct from those stimulated by canonical TLR agonists. Inhibition of long-chain acyl-CoA synthetases (ACSL) by a pharmacological inhibitor or knockdown of ACSL1 blunted the PA-stimulated, but not the LPS- or Pam3CSK4-stimulated proinflammatory responses. Furthermore, triacsin C restored the insulin-stimulated vasodilation, which was impaired by PA. From the results, we concluded that PA stimulates the proinflammatory response in the vascular endothelium through an ACSL1-mediated mechanism, which is distinct from LPS- or Pam3CSK4-stimulated responses. The results suggest that endothelial dysfunction caused by PA may require to undergo intracellular metabolism. This expands the understanding of the mechanisms by which TLRs mediate inflammatory responses in endothelial dysfunction and cardiovascular disease.

Guanosine Neuroprotective Action in Hippocampal Slices Subjected to Oxygen and Glucose Deprivation Restores ATP Levels, Lactate Release and Glutamate Uptake Impairment: Involvement of Nitric Oxide.

Stroke is a major cause of disability and death worldwide. Oxygen and glucose deprivation (OGD) in brain tissue preparations can reproduce several pathological features induced by stroke providing a valuable ex vivo protocol for studying the mechanism of action of neuroprotective agents. Guanosine, an endogenous guanine nucleoside, promotes neuroprotection in vivo and in vitro models of neurotoxicity. We previously showed that guanosine protective effect was mimicked by inhibition of nitric oxide synthases (NOS) activity. This study was designed to investigate the involvement of nitric oxide (NO) in the mechanisms related to the protective role of guanosine in rat hippocampal slices subjected to OGD followed by reoxygenation (OGD/R). Guanosine (100 µM) and the pan-NOS inhibitor, L-NAME (1 mM) afforded protection to hippocampal slices subjected to OGD/R. The presence of NO donors, DETA-NO (800 µM) or SNP (5 µM) increased reactive species production, and abolished the protective effect of guanosine or L-NAME against OGD/R. Guanosine or L-NAME treatment prevented the impaired ATP production, lactate release, and glutamate uptake following OGD/R. The presence of a NO donor also abolished the beneficial effects of guanosine or L-NAME on bioenergetics and glutamate uptake. These results showed, for the first time, that guanosine may regulate cellular bioenergetics in hippocampal slices subjected to OGD/R injury by a mechanism that involves the modulation of NO levels.

Synthesis, characterization, biological evaluation, and in silico studies of novel 1,3-diaryltriazene-substituted sulfathiazole derivatives.

In the present study, a series of eleven novel 1,3-diaryltriazene-substituted sulfathiazole moieties (ST1-11) was synthesized by the reaction of diazonium salt of sulfathiazole with substituted aromatic amines and their chemical structures were characterized by Fourier transform infrared, 1 H-NMR (nuclear magnetic resonance), 13 C-NMR, and high-resolution mass spectroscopy methods. These synthesized novel derivatives were found to be effective inhibitor molecules for α-glycosidase (α-GLY), human carbonic anhydrase (hCA), and acetylcholinesterase (AChE), with KI values in the range of 426.84 ± 58.42-708.61 ± 122.67 nM for α-GLY, 450.37 ± 50.35-1,094.34 ± 111.37 nM for hCA I, 504.37 ± 57.22-1,205.36 ± 195.47 nM for hCA II, and 68.28 ± 10.26-193.74 ± 19.75 nM for AChE. Among the synthesized novel compounds, several lead compounds were investigated against the tested metabolic enzymes. More specifically, ST11 (4-[3-(perfluorophenyl)triaz-1-en-1-yl]-N-(thiazol-2-yl)benzenesulfonamide) showed a highly efficient inhibition profile against hCA I, hCA II, and AChE, with KI values of 450.37 ± 50.35, 504.37 ± 57.22, and 68.28 ± 10.26 nM, respectively. Due to its significant biological inhibitory potency, this derivative may be considered as an interesting lead compound against these enzymes.

Multi-Stress Induction of the Mycobacterium tuberculosis MbcTA Bactericidal Toxin-Antitoxin System.

MbcTA is a type II toxin/antitoxin (TA) system of Mycobacterium tuberculosis. The MbcT toxin triggers mycobacterial cell death in vitro and in vivo through the phosphorolysis of the essential metabolite NAD+ and its bactericidal activity is neutralized by physical interaction with its cognate antitoxin MbcA. Therefore, the MbcTA system appears as a promising target for the development of novel therapies against tuberculosis, through the identification of compounds able to antagonize or destabilize the MbcA antitoxin. Here, the expression of the mbcAT operon and its regulation were investigated. A dual fluorescent reporter system was developed, based on an integrative mycobacterial plasmid that encodes a constitutively expressed reporter, serving as an internal standard for monitoring mycobacterial gene expression, and an additional reporter, dependent on the promoter under investigation. This system was used both in M. tuberculosis and in the fast growing model species Mycobacterium smegmatis to: (i) assess the autoregulation of mbcAT; (ii) perform a genetic dissection of the mbcA promoter/operator region; and (iii) explore the regulation of mbcAT transcription from the mbcA promoter (PmbcA) in a variety of stress conditions, including in vivo in mice and in macrophages.

Synthesis of sulpha drug based hydroxytriazene derivatives: Anti-diabetic, antioxidant, anti-inflammatory activity and their molecular docking studies.

Herein, we report synthesis, characterization, anti-diabetic, anti-inflammatory and anti-oxidant activities of hydroxytriazenes derived from sulpha drugs, namely sulphanilamide, sulphadiazine, sulphapyridine and sulphamethazine. Before biological screening of the compounds, theoretical prediction using PASS was done which indicates probable activities ranging from Pa (probable activity) values 65-98% for anti-inflammatory activity. As per the predication, experimental validation of some of the predicted activities particularly anti-diabetic, anti-inflammatory and anti-oxidant was done. Anti-diabetic activities have been screened using two methods namely α-amylase and α-glucosidase inhibition method and IC50 values were ranging from 66 to 260 and 148 to 401 µg/mL, while for standard drug acarbose the values were 12 µg/mL and 70 µg/mL, respectively. Docking studies have also been done for antidiabetic target pancreatic alpha amylase. The molecular docking studies in α-amylase enzyme reveal that the middle phenyl ring of all the compounds mainly occupies in the small hydrophobic pocket formed by the Ala198, Trp58, Leu162, Leu165 and Ile235 residues and sulphonamide moiety establish H-bond interaction by two water molecules. Further, anti-inflammatory activity has been evaluated using carrageenan induced paw-edema method and results indicate excellent anti-inflammatory activity by hydroxytriazenes (71 to 97%) and standard drug diclofenac 94% after 4 h of treatment. Moreover, antioxidant effect of the compounds was tested using DPPH and ABTS methods. All the compounds displayed good results (24-488 µg/mL) against ABTS radical and many compounds are more active than ascorbic acid (69 µg/mL) while all other compounds showed moderate activity against DPPH radical (292-774 µg/mL) and ascorbic acid (29 µg/mL). Thus, the studies reveal potential of sulfa drug based hydroxytriazenes as candidates for antidiabetic, anti-inflammatory and antioxidant activities which have been experimentally validated.

Access to a Library of 1,3-disubstituted-1,2,3-triazenes and Evaluation of their Antimicrobial Properties.

BACKGROUND: Due to the rapid development of microbial resistance, finding new molecules became urgent to counteract this problem. OBJECTIVE: The objective of this work is to access 1,2,3-triazene-1,3-disubstituted, a class of molecule with high therapeutic potential. METHODS: Here we describe the access to 17 new triazene including six with an imidazole-1,2,3-triazene moiety and eleven with an alkyl-1,2,3-triazene moiety and their evaluation against five strains: two gram (-): Escherichia coli ATCC 25921 and Pseudomonas aeruginosa ATCC 27253; two gram (+) : Staphylococcus aureus ATCC 38213 and Enterococcus faecalis ATCC 29212; and one fungi: Candida albicans ATCC 24433. RESULTS: All strains were sensitive and the best MIC, 0.28 µM, is observed for 4c against Escherichia coli ATCC 25921. Compound 9, 3-isopropynyltriazene, appears to be the most interesting since it is active on the five evaluated strains with satisfactory MIC 0.32 µM against Escherichia coli and Pseudomonas aeruginosa and 0.64 µM against Enterococcus faecalis and Pseudomonas aeruginosa. CONCLUSION: Comparing the structure activity relationship, electron withdrawing groups appear to increase antimicrobial activity.

Novel sulphonamides incorporating triazene moieties show powerful carbonic anhydrase I and II inhibitory properties.

A series of compounds incorporating 3-(3-(2/3/4-substituted phenyl)triaz-1-en-1-yl) benzenesulfonamide moieties were synthesised and their chemical structure was confirmed by physico-chemical methods. Carbonic anhydrase (CA, EC 4.2.1.1) inhibitory effects of the compounds were evaluated against human isoforms hCA I and II. KI values of these sulphonamides were in the range of 21 ± 4-72 ± 2 nM towards hCA I and in the range of 16 ± 6-40 ± 2 nM against hCA II. The 4-fluoro substituted derivative might be considered as an interesting lead due to its effective inhibitory action against both hCA I and hCA II (KIs of 21 nM), a profile rarely seen among other sulphonamide CA inhibitors, making it of interest in systems where the activity of the two cytosolic isoforms is dysregulated.

ACSL1 Regulates TNFα-Induced GM-CSF Production by Breast Cancer MDA-MB-231 Cells.

Overexpression of granulocyte-macrophage colony-stimulating factor (GM-CSF) in different types of cancer is associated with tumor growth and progression. Tumor necrosis factor-α (TNFα) is involved in the induction of GM-CSF in different cells; however, the underlying molecular mechanism in this production of GM-CSF has not been fully revealed. Recently, it was noted that TNFα mediates inflammatory responses through long-chain acyl-CoA synthetase 1 (ACSL1). Therefore, we investigated the role of ACSL1 in the TNFα mediated production of GM-CSF. Our results showed that MDA-MB-231 cells displayed increased GM-CSF mRNA expression and secretion after incubation with TNFα. Blocking of ACSL1 activity in the cells with triacsin C markedly suppressed the secretion of GM-CSF. However, inhibition of ß-oxidation and ceramide biosynthesis were not required for GM-CSF production. By small interfering RNA mediated knockdown, we further demonstrated that TNFα induced GM-CSF production was significantly diminished in ACSL1 deficient cells. TNFα mediated GM-CSF expression was significantly reduced by inhibition of p38 MAPK, ERK1/2 and NF-κB signaling pathways. TNFα induced phosphorylation of p38, ERK1/2, and NF-κB was observed during the secretion of GM-CSF. On the other hand, inhibition of ACSL1 activity attenuates TNFα mediated phosphorylation of p38 MAPK, ERK1/2, and NF-κB in the cells. Importantly, our findings suggest that ACSL1 plays an important role in the regulation of GM-CSF induced by TNFα in MDA-MB-231 cells. Therefore, ACSL1 may be considered as a potential novel therapeutic target for tumor growth.