RESUMEN
The ubiquitous metalloenzymes carbonic anhydrases (CAs, EC 4.2.1.1) are responsible for the reversible hydration of CO2 to bicarbonate (HCO3-) and protons (Hâº). Bicarbonate may subsequently generate carbonate used in many functional activities by marine organisms. CAs play a crucial role in several physiological processes, e.g., respiration, inorganic carbon transport, intra and extra-cellular pH regulation, and bio-mineralization. Multiple transcript variants and protein isoforms exist in the organisms. Recently, 16 α-CA isoforms have been identified in the coral Stylophora pistillata. Here, we focalized the interest on three coral isoforms: SpiCA1 and SpiCA2, localized in the coral-calcifying cells; and SpiCA3, expressed in the cytoplasm of the coral cell layers. The three recombinant enzymes were heterologously expressed and investigated for their inhibition profiles with sulfonamides and sulfamates. The three coral CA isoforms differ significantly in their susceptibility to inhibition with sulfonamides. This study provides new insights into the coral physiology and the comprehension of molecular mechanisms involved in the bio-mineralization processes, since CAs interact with bicarbonate transporters, accelerating the trans-membrane bicarbonate movement and modulating the pH at both sides of the plasma membranes.
Asunto(s)
Antozoos/metabolismo , Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/metabolismo , Sulfonamidas/farmacología , Secuencia de Aminoácidos , Animales , Antozoos/efectos de los fármacos , Antozoos/genética , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/aislamiento & purificación , Genoma , Isoenzimas/antagonistas & inhibidores , Isoenzimas/genética , Isoenzimas/aislamiento & purificación , Isoenzimas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Relación Estructura-ActividadRESUMEN
A series of N'-phenyl-N-hydroxyureas has been prepared by reacting hydroxylamine with aromatic isocyanates. These compounds were investigated as inhibitors of human carbonic anhydrases (hCAs, EC 4.2.1.1), considering four physiologically relevant isoforms, the cytosolic isoforms hCA I and II, and tumor associated, transmembrane isoforms hCA IX and XII. The new compounds reported here did not inhibit the widespread cytosolic isoforms hCA I and II, but they inhibited the tumor associated isoforms with interesting potencies. The most effective inhibitors showed KIs ranging between 72.8 and 78.9â¯nM against hCA IX and between 6.9 and 7.2 against hCA XII, making them of interest as candidates for antitumor studies.
Asunto(s)
Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/metabolismo , Hidroxiurea/farmacología , Inhibidores de Anhidrasa Carbónica/síntesis química , Inhibidores de Anhidrasa Carbónica/química , Relación Dosis-Respuesta a Droga , Humanos , Hidroxiurea/análogos & derivados , Hidroxiurea/química , Isoenzimas/antagonistas & inhibidores , Isoenzimas/metabolismo , Estructura Molecular , Relación Estructura-ActividadRESUMEN
The first activation study of a η-class carbonic anhydrase (CAs, EC 4.2.1.1) is reported. A panel of 24 natural and non-natural amino acids and amines was used to explore the activation profile of Plasmodium falciparum CA (PfACA). The most effective activators belonged to the amino acid chemotype, with d-Glu, l-Asp, l-/d-Phe and l-/d-DOPA possessing activation constant in the range of 82â¯nM-0.75⯵M, whereas l-/d-His, l-Tyr, 4-amino-l-Phe and l-Gln were slightly less effective (KA in the range of 1.00-2.51⯵M. The only amine with submicromolar activating properties was 1-(2-aminoethyl-piperazine) with a KA of 0.71⯵M, whereas histamine, dopamine and serotonin showed KA ranging between 7.18 and 9.97⯵M. As CA activators have scarcely been investigated for their interaction with protozoan CAs, this study may be relevant for an improved understanding of the role of this enzyme in the life cycle of the malaria producing organisms belonging to the genus Plasmodium.
Asunto(s)
Aminas/metabolismo , Aminoácidos/metabolismo , Anhidrasas Carbónicas/metabolismo , Plasmodium falciparum/enzimología , Proteínas Protozoarias/metabolismo , Aminas/química , Aminoácidos/química , Anhidrasas Carbónicas/química , Humanos , Isoenzimas/química , Isoenzimas/metabolismo , Cinética , Estadios del Ciclo de Vida , Proteínas Protozoarias/química , Relación Estructura-ActividadRESUMEN
The inhibition of α-, ß-, γ-, and δ-class carbonic anhydrases (CAs, EC 4.2.1.1) from bacteria (Vibrio cholerae and Porphyromonas gingivalis) and diatoms (Thalassiosira weissflogii) with a panel of N'-aryl-N-hydroxy-ureas is reported. The α-/ß-CAs from V. cholerae (VchCAα and VchCAß) were effectively inhibited by some of these derivatives, with KIs in the range of 97.5 nM - 7.26 µM and 52.5 nM - 1.81 µM, respectively, whereas the γ-class enzyme VchCAγ was less sensitive to inhibition (KIs of 4.75 - 8.87 µM). The ß-CA from the pathogenic bacterium Porphyromonas gingivalis (PgiCAß) was not inhibited by these compounds (KIs > 10 µM) whereas the corresponding γ-class enzyme (PgiCAγ) was effectively inhibited (KIs of 59.8 nM - 6.42 µM). The δ-CA from the diatom Thalassiosira weissflogii (TweCAδ) showed effective inhibition with these derivatives (KIs of 33.3 nM - 8.74 µM). As most of these N-hydroxyureas are also ineffective as inhibitors of the human (h) widespread isoforms hCA I and II (KIs > 10 µM), this class of derivatives may lead to the development of CA inhibitors selective for bacterial/diatom enzymes over their human counterparts and thus to anti-infectives or agents with environmental applications.
Asunto(s)
Inhibidores de Anhidrasa Carbónica/farmacología , Diatomeas/enzimología , Hidroxiurea/farmacología , Isoenzimas/antagonistas & inhibidores , Porphyromonas gingivalis/enzimología , Vibrio cholerae/enzimología , Inhibidores de Anhidrasa Carbónica/aislamiento & purificación , Humanos , Hidroxiurea/químicaRESUMEN
A series of symmetric molecules incorporating aryl or pyridyl moieties as central core and 1,4-substituted triazoles as a side bridge was synthesised. The new compounds were investigated as lactate dehydro-genase (LDH, EC 1.1.1.27) inhibitors. The cancer associated LDHA isoform was inhibited with IC50 = 117-174 µM. Seven compounds exhibited better LDHA inhibition (IC50 117-136 µM) compared to known LDH inhibitor - galloflavin (IC50 157 µM).
Asunto(s)
Inhibidores Enzimáticos/farmacología , Isocumarinas/farmacología , L-Lactato Deshidrogenasa/antagonistas & inhibidores , Triazoles/farmacología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Isocumarinas/química , L-Lactato Deshidrogenasa/metabolismo , Estructura Molecular , Relación Estructura-Actividad , Triazoles/químicaRESUMEN
The α- and ß-class carbonic anhydrases (CAs, EC 4.2.1.1) from the pathogenic bacterium Vibrio cholerae, VchCAα, and VchCAß, were investigated for their activation with natural and non-natural amino acids and amines. The most effective VchCAα activators were L-tyrosine, histamine, serotonin, and 4-aminoethyl-morpholine, which had KAs in the range of 8.21-12.0 µM. The most effective VchCAß activators were D-tyrosine, dopamine, serotonin, 2-pyridyl-methylamine, 2-aminoethylpyridine, and 2-aminoethylpiperazine, which had KAs in the submicromolar - low micromolar range (0.18-1.37 µM). The two bacterial enzymes had very different activation profiles with these compounds, between each other, and in comparison to the human isoforms hCA I and II. Some amines were selective activators of VchCAß, including 2-pyridylmethylamine (KA of 180 nm for VchCAß, and more than 20 µM for VchCAα and hCA I/II). The activation of CAs from bacteria, such as VchCAα/ß has not been considered previously for possible biomedical applications. It would be of interest to study in more detail the extent that CA activators are implicated in the virulence and colonisation of the host by such pathogenic bacteria, which for Vibrio cholerae, is highly dependent on the bicarbonate concentration and pH in the surrounding tissue.
Asunto(s)
Aminas/farmacología , Aminoácidos/farmacología , Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/metabolismo , Vibrio cholerae/enzimología , Aminas/síntesis química , Aminas/química , Aminoácidos/síntesis química , Aminoácidos/química , Inhibidores de Anhidrasa Carbónica/síntesis química , Inhibidores de Anhidrasa Carbónica/química , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Relación Estructura-Actividad , Vibrio cholerae/patogenicidadRESUMEN
The ß-class carbonic anhydrase (CA, EC 4.2.1.1) from the pathogenic bacterium Burkholderia pseudomallei, BpsCAß, that is responsible for the tropical disease melioidosis was investigated for its activation with natural and non-natural amino acids and amines. Previously, the γ-CA from this bacterium has been investigated with the same library of 19 amines/amino acids, which show very potent activating effects on both enzymes. The most effective BpsCAß activators were L- and D-DOPA, L- and D-Trp, L-Tyr, 4-amino-L-Phe, histamine, dopamine, serotonin, 2-pyridyl-methylamine, 1-(2-aminoethyl)-piperazine and L-adrenaline with KAs of 0.9-27 nM. Less effective activators were D-His, L- and D-Phe, D-Tyr, 2-(2-aminoethyl)pyridine and 4-(2-aminoethyl)-morpholine with KAs of 73 nM-3.42 µM. The activation of CAs from bacteria, such as BpsCAγ/ß, has not been considered previously for possible biomedical applications. It would be of interest to perform studies in which bacteria are cultivated in the presence of CA activators, which may contribute to understanding processes connected with the virulence and colonization of the host by pathogenic bacteria.
Asunto(s)
Aminas/metabolismo , Aminoácidos/metabolismo , Burkholderia pseudomallei/enzimología , Anhidrasas Carbónicas/metabolismo , Aminas/química , Aminoácidos/química , Estructura MolecularRESUMEN
The activation of the δ-class carbonic anhydrase (CAs, EC 4.2.1.1) from the diatom Thalassiosira weissflogii (TweCAδ) was investigated using a panel of natural and non-natural amino acids and amines. The most effective activator of TweCAδ was d-Tyr (KA of 51 nM), whereas several other amino acids and amines, such as L-His, L-Trp, d-Trp, dopamine and serotonin were submicromolar activators (KAs from 0.51 to 0.93 µM). The most ineffective activator of TweCAδ was 4-amino-l-Phe (18.9 µM), whereas d-His, l-/d-Phe, l-/d-DOPA, l-Tyr, histamine, some pyridyl-alkylamines, l-adrenaline and aminoethyl-piperazine/morpholine were moderately potent activators (KAs from 1.34 to 8.16 µM). For any δ-CA, there are no data on the crystal structure, homology modelling and the amino acid residues that are responsible for proton transfer to the active site are currently unknown making it challenging to provide a detailed rational for these findings. However, these data provide further evidence that this class of underexplored CA deserves more attention.
Asunto(s)
Aminas/farmacología , Aminoácidos/farmacología , Diatomeas/enzimología , Aminas/química , Aminoácidos/química , Anhidrasas Carbónicas/metabolismo , Humanos , Modelos MolecularesRESUMEN
The activation of a ß-class carbonic anhydrase (CAs, EC 4.2.1.1) from Mycobacterium tuberculosis, encoded by the gene Rv3273 (mtCA 3), was investigated using a panel of natural and non-natural amino acids and amines. mtCA 3 was effectively activated by D-DOPA, L-Trp, dopamine and serotonin, with KAs ranging between 8.98 and 12.1 µM. L-His and D-Tyr showed medium potency activating effects, with KAs in the range of 17.6-18.2 µM, whereas other amines and amino acids were relatively ineffective activators, with KAs in the range of 28.9-52.2 µM. As the physiological roles of the three mtCAs present in this pathogen are currently poorly understood and considering that inhibition of these enzymes has strong antibacterial effects, discovering molecules that modulate their enzymatic activity may lead to a better understanding of the factors related to the invasion and colonisation of the host during Mycobacterium tuberculosis infection.
Asunto(s)
Aminas/metabolismo , Aminoácidos/química , Aminoácidos/metabolismo , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/metabolismo , Mycobacterium tuberculosis/enzimología , Aminas/química , Estructura Molecular , Mycobacterium tuberculosis/genéticaRESUMEN
Carbonic anhydrases (CAs, EC 4.2.1.1) are widespread metalloenzymes used by living organisms to accelerate the CO2 hydration/dehydration reaction at rates dramatically high compared to the uncatalyzed reaction. These enzymes have different isoforms and homologues and can be found in the form of cytoplasmic, secreted or membrane-bound proteins. CAs play a role in numerous physiological processes including biomineralization and symbiosis, as is the case in reef-building corals. Previously, molecular and biochemical data have been obtained at the molecular level in the branching coral Stylophora pistillata for two coral isoforms which differ significantly in their catalytic activity and susceptibility to inhibition with anions and sulfonamides. More recently it has been determined that the genome of S. pistillata encodes for 16 CAs. Here, we cloned, expressed, purified and characterized a novel α-CA, named SpiCA3, which is cytoplasmic and ubiquitously expressed in all the cell layers including the calcifying cells. SpiCA3 is the most effective CA among the coral isoforms investigated and the most efficient catalyst known up to date in Metazoa. We also investigated the inhibition profiles of SpiCA3 and compared it with those obtained for the two other isoforms in the presence of inorganic anions and other small molecules known to interfere with metalloenzymes. These results suggest that S. pistillata has adapted its CA isoforms to achieve the physiological functions in different physicochemical microenvironments.
Asunto(s)
Antozoos/enzimología , Anhidrasas Carbónicas/metabolismo , Isoformas de Proteínas/metabolismo , Proteínas Recombinantes/metabolismo , Secuencia de Aminoácidos , Animales , Anhidrasas Carbónicas/química , Anhidrasas Carbónicas/genética , Datos de Secuencia Molecular , Isoformas de Proteínas/genética , Proteínas Recombinantes/genéticaRESUMEN
Total extracts of Drechslera rostrata and Eurotium tonophilum in addition of two isolated compounds from their cultures [di-2-ethylhexyl phthalate (H1) and 1,8-Dihydroxy-3-methoxy-6-methyl-anthraquinone (H2)] were tested for their antitumor activity using four human carcinoma cell lines. Antitumor activity was assessed by performing MTT assay to check the % cell viability. The % viability of HCT-116 (colon carcinoma), HeLa (cervical carcinoma), HEp-2 (larynx carcinoma) and HepG-2 (hepatocellular carcinoma) cells decreased after treatment with Drechslera rostrata and Eurotium tonophilum extracts, these effects were ranged from 059.0 ± â¯0.1 to 217.0⯠± â¯0.3⯵g/ml on all types of cancer cells. The best activity was recorded for Eurotium tonpholium extract (054.5⯱â¯0.3, 059.0⯱â¯0.5 and 059.0⯱â¯0.1 for HEp-2, Hela, and HepG-2 respectively). The isolated compounds (H1&H2) were found to be responsible about the activities because they recorded the lowest IC50 on tested cell lines with range of 9.5-20.3⯵g/ml. Vinblastine sulphate was used as a reference standard and showed in vitro anticancer activity. This study demonstrated that all extracts and isolated compounds have antitumor activity against HCT-116, HeLa, HEp-2 and HepG-2 cells.
RESUMEN
Two novel quinazoline derivatives named as; 3-[(4-hydroxy-3-methoxy-benzylidene)-amino]-2-p-tolyl-3H-quinazolin-4-one (5) and 2-p-Tolyl-3-[3,4,5-trimethoxy-benzylidene-amino]-3H-quinazolin-4-one (6) in addition to one acetamide derivative named as 2-(2-Hydroxycarbonylphenylamino)-N-(4-aminosulphonylphenyl) 11 were synthesized, and evaluated for their anti-ulcerogenic & Anti-Ulcerative colitis activities. All of the three compounds showed curative activity against acetic acid induced ulcer model at a dose of 50 mg/kg, they produced 65%, 85% & 57.74% curative ratio for compounds 5, 6 & 11 respectively. The effect of the tested compounds 5, 6 & 11 at dose 50â¯mg/kg were significantly (P < 0.01) more effective than dexamesathone (0.1â¯mg/kg) in reducing all parameters. Compounds showed curative activity of for peptic ulcer (induced by absolute alcohol (at a dose of 50â¯mg/kg, it produced Curative of control ulcer 56.00%, 61.70% & 87.1% for compounds 5, 6 & 11 respectively at dose 50â¯mg/kg, while the standard drug (Omeprazole 20â¯mg/kg) produced 33.3%. In both tests, the activity of our target compounds were higher than the standard drugs used for treatment of peptic ulcer and ulcerative colitis. No side effects were reported on liver and kidney functions upon prolonged oral administration of this compounds.
RESUMEN
A series of monothiocarbamates (MTCs) was investigated for the inhibition of the ß-class carbonic anhydrase (CAs, EC 4.2.1.1) from the fungal parasite Malassezia globosa, MgCA. These MTCs incorporate various scaffolds, among which aliphatic amine with 1-4 carbons atom in their molecule, morpholine, piperazine, as well as phenethylamine and benzylamine derivatives. All the reported MTCs displayed a better efficacy in inhibiting MgCA compared to the clinically used sulphonamide drug acetazolamide (KI of 74 µM), with KIs spanning between 1.85 and 18.9 µM. The homology model of the enzyme previously reported by us was used to rationalize the results by docking some of these MTCs within the fungal CA active site. This study might be useful to enrich the knowledge of the MgCA inhibition profile, eliciting novel ideas pertaining the design of modulators with potential efficacy in combatting dandruff or other fungal infections.
Asunto(s)
Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/metabolismo , Malassezia/química , Tiocarbamatos/farmacología , Inhibidores de Anhidrasa Carbónica/química , Inhibidores de Anhidrasa Carbónica/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad , Tiocarbamatos/química , Tiocarbamatos/aislamiento & purificaciónRESUMEN
The carbonic anhydrase superfamily (CA, EC 4.2.1.1) of metalloenzymes is present in all three domains of life (Eubacteria, Archaea, and Eukarya), being an interesting example of convergent/divergent evolution, with its seven families (α-, ß-, γ-, δ-, ζ-, η-, and θ-CAs) described so far. CAs catalyse the simple, but physiologically crucial reaction of carbon dioxide hydration to bicarbonate and protons. Recently, our groups characterised the α-CA from the thermophilic bacterium, Sulfurihydrogenibium yellowstonense finding a very high catalytic activity for the CO2 hydration reaction (kcat = 9.35 × 105 s-1 and kcat/Km = 1.1 × 108 M-1 s-1) which was maintained after heating the enzyme at 80 °C for 3 h. This highly thermostable SspCA was covalently immobilised within polyurethane foam and onto the surface of magnetic Fe3O4 nanoparticles. Here, we describe a one-step procedure for immobilising the thermostable SspCA directly on the surface membrane of Escherichia coli, using the INPN domain of Pseudomonas syringae. This strategy has clear advantages with respect to other methods, which require as the first step the production and the purification of the biocatalyst, and as the second step the immobilisation of the enzyme onto a specific support. Our results demonstrate that thermostable SspCA fused to the INPN domain of P. syringae ice nucleation protein (INP) was correctly expressed on the outer membrane of engineered E. coli cells, affording for an easy approach to design biotechnological applications for this highly effective thermostable catalyst.
Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Anhidrasas Carbónicas/metabolismo , Escherichia coli/metabolismo , Bacterias Gramnegativas Quimiolitotróficas/enzimología , Temperatura , Relación Estructura-Actividad , Propiedades de SuperficieRESUMEN
Elevated blood glucose and increased activities of secreted phospholipase A2 (sPLA2) are strongly linked to coronary heart disease. In this report, our goal was to develop small heterocyclic compound that inhibit sPLA2. The title compounds were also tested against α-glucosidase and α-amylase. This array of enzymes was selected due to their implication in blood glucose regulation and diabetic cardiovascular complications. Therefore, two distinct series of quinoxalinone derivatives were synthesised; 3-[N'-(substituted-benzylidene)-hydrazino]-1H-quinoxalin-2-ones 3a-f and 1-(substituted-phenyl)-5H-[1,2,4]triazolo[4,3-a]quinoxalin-4-ones 4a-f. Four compounds showed promising enzyme inhibitory effect, compounds 3f and 4b-d potently inhibited the catalytic activities of all of the studied proinflammatory sPLA2. Compound 3e inhibited α-glucosidase (IC50 = 9.99 ± 0.18 µM); which is comparable to quercetin (IC50 = 9.93 ± 0.66 µM), a known inhibitor of this enzyme. Unfortunately, all compounds showed weak activity against α-amylase (IC50 > 200 µM). Structure-based molecular modelling tools were utilised to rationalise the SAR compared to co-crystal structures with sPLA2-GX as well as α-glucosidase. This report introduces novel compounds with dual activities on biochemically unrelated enzymes mutually involved in diabetes and its complications.
Asunto(s)
Inhibidores Enzimáticos/farmacología , Fosfolipasas A2 Secretoras/antagonistas & inhibidores , Quinoxalinas/farmacología , alfa-Glucosidasas/metabolismo , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Humanos , Modelos Moleculares , Estructura Molecular , Fosfolipasas A2 Secretoras/metabolismo , Quinoxalinas/síntesis química , Quinoxalinas/química , Relación Estructura-ActividadRESUMEN
We cloned, expressed, purified, and determined the kinetic constants of the recombinant α-carbonic anhydrase (rec-MgaCA) identified in the mantle tissue of the bivalve Mediterranean mussel, Mytilus galloprovincialis. In metazoans, the α-CA family is largely represented and plays a pivotal role in the deposition of calcium carbonate biominerals. Our results demonstrated that rec-MgaCA was a monomer with an apparent molecular weight of about 32 kDa. Moreover, the determined kinetic parameters for the CO2 hydration reaction were kcat = 4.2 × 105 s-1 and kcat/Km of 3.5 × 107 M-1 ×s-1. Curiously, the rec-MgaCA showed a very similar kinetic and acetazolamide inhibition features when compared to those of the native enzyme (MgaCA), which has a molecular weight of 50 kDa. Analysing the SDS-PAGE, the protonography, and the kinetic analysis performed on the native and recombinant enzyme, we hypothesised that probably the native MgaCA is a multidomain protein with a single CA domain at the N-terminus of the protein. This hypothesis is corroborated by the existence in mollusks of multidomain proteins with a hydratase activity. Among these proteins, nacrein is an example of α-CA multidomain proteins characterised by a single CA domain at the N-terminus part of the entire protein.
Asunto(s)
Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/aislamiento & purificación , Mytilus/enzimología , Animales , Clonación Molecular , Mytilus/genéticaRESUMEN
The Novel target compounds (CP-1-7) were synthesized and tested at doses up to 1000 mg/kg for their entitled activities. They exerted promising results without any behavioral changes and mortality in mice. Therefore, according to the results obtained in our study, it could be categorized as highly safe agents for treating UC since substances possessing LD50 higher than 50 mg/kg are considered nontoxic. They also possessed a potent anti-ulcerogenic activity with different potentials. The most effective compound was CP-4, it produced 97.7% ulcer protection of control followed by CP-3, which produced 90.3% protection, while the standard drug ranitidine (100 mg/kg) produced 49.2% protection. Compound CP-1 showed lowest activity among the current series, it produced 55.5% protection. The target compounds were significantly more effective than the standard in reducing ulcer index. The anti-ulcerative colitis activity was tested using acetic acid induced colitis model. The curative effect of the tested compounds at a dose of 50 mg/kg oral administration on rats showed a potent anti-ulcerative colitis activity with different potentials. They induced a significant decrease in ulcer score, ulcer area, ulcer index and weight/length of the colon specimens. The percent protection of control colitis ranged from 66.8% for CP-7 to 22.3% for CP-5; however the percent protection for dexamesathone (0.1 mg/kg) was 59.3%. The effect of the tested compounds CP-7 and CP-3 at dose 50 mg/kg were significantly more effective than dexamesathone (0.1 mg/kg) in reducing all parameters. Liver functions were not affected as there is no effect on the activity of both AST and ALT in animals that received the compounds, so the compounds didn't reveal hepatotoxic manifestation. Although, the results on kidney functions showed that, CP-1 slightly elevated blood urea concentration and CP-3 & CP-4 slightly elevated serum creatinine; no apparent nephrotoxic manifestations were recorded.
RESUMEN
A novel and safe essential amino acid (Leucine) incorporating sulfanilamide was synthesized, and evaluated for its anti-ulcerogenic activity and in vitro anti-Helicobacter pylori activity. The new molecule showed a dose dependent activity against absolute ethanol-induced ulcer in rats, it produced percent protection of control ulcer by 66.7 at dose 100 mg/kg. In addition it showed a potent anti-Helicobacter pylori activity in vitro against 7 clinically isolated strains. The minimum inhibitory concentration (MIC) ranged from 12.5 to 50 µg/ml. The preliminary safety studies and toxicity profile are optimistic and encouraging.
RESUMEN
Condensation of substituted anthranilic acids with 4-isothiocyanatoethyl-benzenesulfonamide led to series of heterocyclic benzenesulfonamides incorporating 2-mercapto-quinazolin-4-one tails. These sulfonamides were investigated as inhibitors of the human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms hCA I and II (cytosolic isozymes), as well as hCA XII (a transmembrane, tumor-associated enzyme also involved in glaucoma-genesis). The new sulfonamides acted as medium potency inhibitors of hCA I (KIs of 28.5-2954nM), being highly effective as hCA II (KIs in the range of 0.62-12.4nM) and XII (KIs of 0.54-7.11nM) inhibitors. All substitution patterns present in these compounds (e.g., halogens, methyl and methoxy moieties, in positions 6, 7 and/or 8 of the 2-mercapto-quinazolin-4-one ring) led to highly effective hCA II/XII inhibitors. These compounds should thus be of interest as preclinical candidates in pathologies in which the activity of these enzymes should be inhibited, such as glaucoma (CA II and XII as targets) or some tumors in which the activity of isoforms CA II and XII is dysregulated.
Asunto(s)
Anhidrasa Carbónica II/antagonistas & inhibidores , Inhibidores de Anhidrasa Carbónica/química , Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/metabolismo , Sulfonamidas/química , Sulfonamidas/farmacología , Anhidrasa Carbónica II/metabolismo , Inhibidores de Anhidrasa Carbónica/síntesis química , Humanos , Quinazolinonas/síntesis química , Quinazolinonas/química , Quinazolinonas/farmacología , Sulfonamidas/síntesis química , BencenosulfonamidasRESUMEN
A library of 53 benzimidazole derivatives, with substituents at positions 1, 2 and 5, were synthesized and screened against a series of reference strains of bacteria and fungi of medical relevance. The SAR analyses of the most promising results showed that the antimicrobial activity of the compounds depended on the substituents attached to the bicyclic heterocycle. In particular, some compounds displayed antibacterial activity against two methicillin-resistant Staphylococcus aureus (MRSA) strains with minimum inhibitory concentrations (MICs) comparable to the widely-used drug ciprofloxacin. The compounds have some common features; three possess 5-halo substituents; two are derivatives of (S)-2-ethanaminebenzimidazole; and the others are derivatives of one 2-(chloromethyl)-1H-benzo[d]imidazole and (1H-benzo[d]imidazol-2-yl)methanethiol. The results from the antifungal screening were also very interesting: 23 compounds exhibited potent fungicidal activity against the selected fungal strains. They displayed equivalent or greater potency in their MIC values than amphotericin B. The 5-halobenzimidazole derivatives could be considered promising broad-spectrum antimicrobial candidates that deserve further study for potential therapeutic applications.