Niemann-Pick type C (NPC) disease is a lysosomal storage disorder arising from mutations in the cholesterol-trafficking protein NPC1 (95%) or NPC2 (5%). These mutations result in accumulation of low-density lipoprotein-derived cholesterol in late endosomes/lysosomes, disruption of endocytic trafficking, and stalled autophagic flux. Additionally, NPC disease results in sphingolipid accumulation, yet it is unique among the sphingolipidoses because of the absence of mutations in the enzymes responsible for sphingolipid degradation. In this work, we examined the cause for sphingosine and sphingolipid accumulation in multiple cellular models of NPC disease and observed that the activity of sphingosine kinase 1 (SphK1), one of the two isoenzymes that phosphorylate sphingoid bases, was markedly reduced in both NPC1 mutant and NPC1 knockout cells. Conversely, SphK1 inhibition with the isotype-specific inhibitor SK1-I in WT cells induced accumulation of cholesterol and reduced cholesterol esterification. Of note, a novel SphK1 activator (SK1-A) that we have characterized decreased sphingoid base and complex sphingolipid accumulation and ameliorated autophagic defects in both NPC1 mutant and NPC1 knockout cells. Remarkably, in these cells, SK1-A also reduced cholesterol accumulation and increased cholesterol ester formation. Our results indicate that a SphK1 activator rescues aberrant cholesterol and sphingolipid storage and trafficking in NPC1 mutant cells. These observations highlight a previously unknown link between SphK1 activity, NPC1, and cholesterol trafficking and metabolism.

• Keywords
• NPC1, Niemann–Pick type C, cholesterol, genetic disorder, lipid metabolism, lysosomal storage disease, neurodegeneration, sphingolipid, sphingolipids, sphingosine kinase, sphingosine kinase (SphK), sphingosine-1-phosphate (S1P),
• MeSH
• Cell Line MeSH
• Cholesterol metabolism   MeSH
• Endosomes metabolism   MeSH
• Cholesterol Esters metabolism   MeSH
• Fibroblasts MeSH
• Phosphotransferases (Alcohol Group Acceptor) metabolism   MeSH
• Intracellular Signaling Peptides and Proteins metabolism   MeSH
• Humans MeSH
• Lysosomes metabolism   MeSH
• Membrane Glycoproteins metabolism   MeSH
• Mice MeSH
• Niemann-Pick Disease, Type C metabolism   physiopathology   MeSH
• Primary Cell Culture MeSH
• Niemann-Pick C1 Protein genetics   metabolism   MeSH
• Sphingolipids metabolism   MeSH
• Sphingosine genetics   metabolism   MeSH
• Protein Transport MeSH
• Carrier Proteins metabolism   MeSH
• Vesicular Transport Proteins genetics   metabolism   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Research Support, N.I.H., Extramural MeSH
• Names of Substances
• Cholesterol MeSH
• Cholesterol Esters MeSH
• Phosphotransferases (Alcohol Group Acceptor) MeSH
• Intracellular Signaling Peptides and Proteins MeSH
• Membrane Glycoproteins MeSH
• NPC2 protein, human MeSH Browser
• Niemann-Pick C1 Protein MeSH
• Sphingolipids MeSH
• Sphingosine MeSH
• sphingosine kinase MeSH Browser
• Carrier Proteins MeSH
• Vesicular Transport Proteins MeSH

1-[2-[({[2-/3-(Alkoxy)phenyl]amino}carbonyl)oxy]-3-(dipropylammonio)propyl]pyrrolidinium/azepan- ium oxalates or dichlorides (alkoxy = butoxy to heptyloxy) were recently described as very promising antimycobacterial agents. These compounds were tested in vitro against Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212 (reference and control strains), three methicillin-resistant isolates of S. aureus, and three isolates of vancomycin-resistant E. faecalis. 1-[3-(Dipropylammonio)-2-({[3-(pentyloxy-/hexyloxy-/heptyloxy)phenyl]carbamoyl}oxy)propyl]pyrrolidinium dichlorides showed high activity against staphylococci and enterococci comparable with or higher than that of used controls (clinically used antibiotics and antiseptics). The screening of the cytotoxicity of the compounds as well as the used controls was performed using human monocytic leukemia cells. IC50 values of the most effective compounds ranged from ca. 3.5 to 6.3 µM, thus, it can be stated that the antimicrobial effect is closely connected with their cytotoxicity. The antibacterial activity is based on the surface activity of the compounds that are influenced by the length of their alkoxy side chain, the size of the azacyclic system, and hydro-lipophilic properties, as proven by in vitro experiments and chemometric principal component analyses. Synergistic studies showed the increased activity of oxacillin, gentamicin, and vancomycin, which could be explained by the direct activity of the compounds against the bacterial cell wall. All these compounds demonstrate excellent antibiofilm activity, when they inhibit and disrupt the biofilm of S. aureus in concentrations close to minimum inhibitory concentrations against planktonic cells. Expected interactions of the compounds with the cytoplasmic membrane are proven by in vitro crystal violet uptake assays.

• Keywords
• antibacterial, antibiofilm activity, carbamate, structure–activity relationships, synergy,
• Publication type
• Journal Article MeSH

Novel 1-(2-{3-/4-[(alkoxycarbonyl)amino]phenyl}-2-hydroxyethyl)-4-(2-fluorophenyl)-piperazin-1-ium chlorides (alkoxy = methoxy to butoxy; 8a-h) have been designed and synthesized through multistep reactions as a part of on-going research programme focused on finding new antimycobacterials. Lipophilic properties of these compounds were estimated by RP-HPLC using methanol/water mobile phases with a various volume fraction of the organic modifier. The log kw values, which were extrapolated from intercepts of a linear relationship between the logarithm of a retention factor k (log k) and volume fraction of a mobile phase modifier (ϕM), varied from 2.113 (compound 8e) to 2.930 (compound 8h) and indicated relatively high lipophilicity of these salts. Electronic properties of the molecules 8a-h were investigated by evaluation of their UV/Vis spectra. In a next phase of the research, the compounds 8a-h were in vitro screened against M. tuberculosis CNCTC My 331/88 (identical with H37Rv and ATCC 2794), M. kansasii CNCTC My 235/80 (identical with ATCC 12478), a M. kansasii 6 509/96 clinical isolate, M. avium CNCTC My 330/80 (identical with ATCC 25291) and M. avium intracellulare ATCC 13950, respectively, as well as against M. kansasii CIT11/06, M. avium subsp. paratuberculosis CIT03 and M. avium hominissuis CIT10/08 clinical isolates using isoniazid, ethambutol, ofloxacin, ciprofloxacin or pyrazinamide as reference drugs. The tested compounds 8a-h were found to be the most promising against M. tuberculosis; a MIC = 8 μM was observed for the most effective 1-(2-{4-[(butoxycarbonyl)amino]phen-ylphenyl}-2-hydroxyethyl)-4-(2-fluorophenyl)piperazin-1-ium chloride (8h). In addition, all of them showed low (insignificant) in vitro toxicity against a human monocytic leukemia THP-1 cell line, as observed LD50 values > 30 μM indicated. The structure-antimycobacterial activity relationships of the analyzed 8a-h series are also discussed.

• Keywords
• Mycobacterium tuberculosis H37Rv, N-arylpiperazines, arylaminoethanols, electronic properties, lipophilicity,
• MeSH
• Antitubercular Agents chemical synthesis   chemistry   pharmacology   MeSH
• Hydrophobic and Hydrophilic Interactions MeSH
• Humans MeSH
• Microbial Sensitivity Tests MeSH
• Molecular Structure MeSH
• Mycobacterium tuberculosis drug effects   MeSH
• Cell Line, Tumor MeSH
• Piperazines chemical synthesis   chemistry   pharmacology   MeSH
• Spectrum Analysis MeSH
• Cell Survival drug effects   MeSH
• Structure-Activity Relationship MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Antitubercular Agents MeSH
• Piperazines MeSH

Tertiary amines 3-(dialkylamino)-2-hydroxypropyl 4-[(alkoxycarbonyl)amino]benzoates and their quaternary ammonium salts were synthesized. The final step of synthesis of quaternary ammonium salts was carried out by microwave-assisted synthesis. Software-calculated data provided the background needed to compare fifteen new resulting compounds by their physicochemical properties. The acid dissociation constant (pKa) and lipophilicity index (log P) of tertiary amines were determined; while quaternary ammonium salts were characterized by software-calculated lipophilicity index and surface tension. Biological evaluation aimed at testing acetylcholinesterase and butyrylcholinesterase-inhibiting activity of synthesized compounds. A possible mechanism of action of these compounds was determined by molecular modelling study using combined techniques of docking; molecular dynamics simulations and quantum mechanics calculations.

• Keywords
• acetylcholinesterase, arylcarbonyloxyaminopropanols, butyrylcholinesterase, quaternary ammonium salts, tertiary amines,
• MeSH
• Acetylcholinesterase MeSH
• Enzyme Activation drug effects   MeSH
• Benzoates chemical synthesis   chemistry   pharmacology   MeSH
• Butyrylcholinesterase MeSH
• Models, Chemical MeSH
• Cholinesterase Inhibitors chemical synthesis   chemistry   pharmacology   MeSH
• Quaternary Ammonium Compounds chemical synthesis   chemistry   pharmacology   MeSH
• Models, Molecular * MeSH
• Salts chemistry   MeSH
• Chemistry Techniques, Synthetic * MeSH
• Protein Binding MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Acetylcholinesterase MeSH
• Benzoates MeSH
• Butyrylcholinesterase MeSH
• Cholinesterase Inhibitors MeSH
• Quaternary Ammonium Compounds MeSH
• Salts MeSH

Sphingosine kinase 1 (SphK1), the enzyme that produces the bioactive sphingolipid metabolite, sphingosine-1-phosphate, is a promising new molecular target for therapeutic intervention in cancer and inflammatory diseases. In view of its importance, the main objective of this work was to find new and more potent inhibitors for this enzyme possessing different structural scaffolds than those of the known inhibitors. Our theoretical and experimental study has allowed us to identify two new structural scaffolds (three new compounds), which could be used as starting structures for the design and then the development of new inhibitors of SphK1. Our study was carried out in different steps: virtual screening, synthesis, bioassays and molecular modelling. From our results, we propose a new dihydrobenzo[b]pyrimido[5,4-f]azepine and two alkyl{3-/4-[1-hydroxy-2-(4-arylpiperazin-1-yl)ethyl]phenyl}carbamates as initial structures for the development of new inhibitors. In addition, our molecular modelling study using QTAIM calculations, allowed us to describe in detail the molecular interactions that stabilize the different Ligand-Receptor complexes. Such analyses indicate that the cationic head of the different compounds must be refined in order to obtain an increase in the binding affinity of these ligands.

• Keywords
• Bioassays, Molecular modelling, Sphingosine kinase 1 inhibitors, Synthesis, Virtual screening,
• MeSH
• Phosphotransferases (Alcohol Group Acceptor) antagonists & inhibitors   metabolism   MeSH
• Protein Kinase Inhibitors chemical synthesis   chemistry   pharmacology   MeSH
• Quantum Theory MeSH
• Models, Molecular MeSH
• Molecular Structure MeSH
• Dose-Response Relationship, Drug MeSH
• Structure-Activity Relationship MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Phosphotransferases (Alcohol Group Acceptor) MeSH
• Protein Kinase Inhibitors MeSH
• sphingosine kinase MeSH Browser

This research was focused on in silico characterization and in vitro biological testing of the series of the compounds carrying a N-arylpiperazine moiety. The in silico investigation was based on the prediction of electronic, steric and lipohydrophilic features. The molecules were screened against Mycobacterium avium subsp. paratuberculosis CIT03, M. smegmatis ATCC 700084, M. kansasii DSM 44162, M. marinum CAMP 5644, Staphylococcus aureus ATCC 29213, methicillin-resistant S. aureus 63718, Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212, Candida albicans CCM 8261, C. parapsilosis CCM 8260 and C. krusei CCM 8271, respectively, by standardized microdilution methods. The eventual antiproliferative (cytotoxic) impact of those compounds was examined on a human monocytic leukemia THP-1 cell line, as a part of the biological study. Promising potential against M. kansasii was found for 1-[3-(3-ethoxyphenylcarbamoyl)oxy-2-hydroxypropyl]-4-(3-trifluoromethylphenyl)piperazin-1-ium chloride (MIC = 31.75 μM), which was comparable to the activity of isoniazid (INH; MIC = 29.17 μM). Moreover, 1-{2-hydroxy-3-(3-methoxyphenylcarbamoyl)oxy)propyl}-4-(4-fluorophenyl)piperazin-1-ium chloride was even more effective (MIC = 17.62 μM) against given mycobacterium. Among the tested N-arylpiperazines, 1-{2-hydroxy-3-(4-methoxyphenylcarbamoyl)oxy)propyl}-4-(3-trifluorometh-ylphenyl)piperazin-1-ium chloride was the most efficient against M. marinum (MIC = 65.32 μM). One of the common features of all investigated substances was their insignificant antiproliferative (i.e., non-cytotoxic) effect. The study discussed structure-antimicrobial activity relationships considering electronic, steric and lipophilic properties.

• Keywords
• Mycobacterium kansasii, Mycobacterium marinum, N-arylpiperazines, electronic properties, lipophilicity, structure–activity,
• Publication type
• Journal Article MeSH

Series of thirteen 1-[(2-chlorophenyl)carbamoyl]naphthalen-2-yl carbamates and thirteen 1-[(2-nitrophenyl)carbamoyl]naphthalen-2-yl carbamates with alkyl/cycloalkyl/arylalkyl chains were prepared and characterized. Primary in vitro screening of the synthesized compounds was performed against Staphylococcus aureus, two methicillin-resistant S. aureus strains, Mycobacterium marinum, and M. kansasii. 1-[(2-Chlorophenyl)carbamoyl]naphthalen-2-yl ethylcarbamate and 1-[(2-nitrophenyl)carbamoyl]naphthalen-2-yl ethylcarbamate showed antistaphylococcal (MICs = 42 µM against MRSA) and antimycobacterial (MICs = 21 µM) activity against the tested strains comparable with or higher than that of the standards ampicillin and isoniazid. In the case of bulkier carbamate tails (R > propyl/isopropyl), the activity was similar (MICs ca. 70 µM). Screening of the cytotoxicity of both of the most effective compounds was performed using THP-1 cells, and no significant lethal effect was observed (LD50 >30 µM). The structure-activity relationships are discussed.

• Keywords
• carbamates, hydroxynaphthalene-carboxamides, in vitro antibacterial activity, in vitro antimycobacterial activity, in vitro cytotoxicity assay, structure-activity relationships,
• MeSH
• Anti-Infective Agents * chemical synthesis   chemistry   pharmacology   MeSH
• Cytotoxins * chemical synthesis   chemistry   pharmacology   MeSH
• Carbamates * chemical synthesis   chemistry   pharmacology   MeSH
• Humans MeSH
• Methicillin-Resistant Staphylococcus aureus growth & development   MeSH
• Mycobacterium tuberculosis growth & development   MeSH
• Cell Line, Tumor MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Anti-Infective Agents * MeSH
• Cytotoxins * MeSH
• Carbamates * MeSH

A series of twelve 2-[(E)-2-substituted-ethenyl]-1,3-benzoxazoles was designed. All the synthesized compounds were tested against three mycobacterial strains. The compounds were also evaluated for their ability to inhibit photosynthetic electron transport (PET) in spinach (Spinacia oleracea L.) chloroplasts. 2-[(E)-2-(4-Methoxyphenyl)ethenyl]-1,3-benzoxazole, 2-[(E)-2-(2,3-dihydro-1-benzofuran-5-yl)ethenyl]-1,3-benzoxazole and 2-{(E)-2-[4-(methylsulfanyl)phenyl]ethenyl}-1,3-benzoxazole showed the highest activity against M. tuberculosis, M. kansasii, and M. avium, and they demonstrated significantly higher activity against M. avium and M. kansasii than isoniazid. The PET-inhibiting activity of the most active ortho-substituted compound 2-[(E)-2-(2-methoxyphenyl)ethenyl]-1,3-benzoxazole was IC₅₀ = 76.3 μmol/L, while the PET-inhibiting activity of para-substituted compounds was significantly lower. The site of inhibitory action of tested compounds is situated on the donor side of photosystem II. The structure-activity relationships are discussed.

• MeSH
• Anti-Bacterial Agents chemical synthesis   chemistry   pharmacology   MeSH
• Benzoxazoles chemical synthesis   chemistry   pharmacology   MeSH
• Chloroplasts metabolism   MeSH
• Species Specificity MeSH
• Photosynthesis drug effects   MeSH
• Inhibitory Concentration 50 MeSH
• Mycobacteriaceae drug effects   MeSH
• Spinacia oleracea MeSH
• Electron Transport drug effects   MeSH
• Structure-Activity Relationship MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Anti-Bacterial Agents MeSH
• Benzoxazoles MeSH