Inhibition Of Ca2 Research Articles

Populus euphratica R2R3-MYB transcription factor RAX2 binds ANN1 promoter to increase cadmium enrichment in Arabidopsis

The expression of R2R3-MYB transcription factor PeRAX2 increased transiently upon CdCl2 exposure (100 μM, 48 h) in leaves and roots of Populus euphratica. We observed that overexpression of PeRAX2 increased Cd2+ concentration in Arabidopsis root cells and Cd2+ amount in whole plant, which was due to the increased Cd2+ influx into root tips. However, the Cd2+ influx facilitated by PeRAX2 overexpression was substantially reduced by LaCl3 (an inhibitor of Ca2+-channels), suggesting that PeRAX2 could promote the Cd2+ entering through PM Ca2+-permeable channels (CaPCs) in the roots. It is noting that the expression of annexin1 (AtANN1), which mediates the influx of divalent cations through the PM calcium channels, was upregulated by Cd2+ in PeRAX2-transgenic Arabidopsis. Bioinformatic analysis revealed that the AtANN1 promoter (AtANN1-pro) contains four cis-elements for MYB binding. The PeRAX2 interaction with AtANN1-pro was validated by LUC reporter assay, EMSA, and Y1H assay. Our data showed that PeRAX2 binds to the AtANN1 promoter region to regulate gene transcription and that AtANN1 mediates the Cd2+ entry through CaPCs in the PM, leading to a Cd2+ enrichment in transgenic plants. The PeRAX2-stimulated Cd2+ enrichment consequently resulted in high H2O2 production in root cells of transgenic plants. The expression of AtSOD and AtPOD and activities of CAT, SOD, POD increased in the transgenic lines under Cd2+ stress. However, the Cd2+-upregulated expression and activity of antioxidative enzymes were less pronounced in the PeRAX2-overexpressed lines, compared to the wildtype and vector controls. As a result, root length and plant growth were more suppressed by Cd2+ in the transgenic lines. Our data suggest that transcriptional regulation of AtANN1 by PeRAX2 can be utilized to improve Cd2+ enrichment and phytoremediation, although the enriched Cd2+ affected antioxidant defense system and plant growth in the model species.

Experience in managing patients with X-linked congenital retinoschisis

AIM: To describe the clinical manifestations and management experience of patients with X-linked congenital retinoschisis (XLRS).
 MATERIAL AND METHODS: The study was conducted in the ophthalmology department of the multidisciplinary clinical medical center Bonum (Yekaterinburg). Two brothers with XLRS were under observation. They underwent complete ophthalmological examinations, including electrophysiological examinations, optical coherence tomography (OCT), and fundus photoregistration. The mother refused genetic testing.
 RESULTS: Both siblings had early (up to 1 year) manifestations of central foveolamellar and peripheral bullous retinoschisis. The parents are phenotypically healthy, and the relatives have no hereditary eye diseases. The younger brother had a progressive peripheral retinoschisis and underwent barrier laser retinopexy; as a result, the progression stopped at the last examination. Acetazolamide 125 mg given orally daily for 4 weeks did not have a noticeable effect on the volume of bullous cavities. The older brother had been under observation for 4 years, and spontaneous closure of retinal cavities on the periphery in one eye and retinal detachment in the other after surgical treatment of retinoschisis were observed.
 CONCLUSION: Clinical cases of long-term follow-up of two brothers with XLRS are described. OCT is indicated to diagnose, assess the length and the state of the vitreoretinal interface, and monitor XLRS. Electroretignography is a specific and sensitive method for the complex diagnosis of XLRS. Barrier laser retinopexy is indicated for progressive peripheral retinoschisis. The efficacy and safety of carbonic anhydrase inhibitors in patients with XLRS require further study.

Identification, crystallization, and first X-ray structure analyses of phenyl boronic acid-based inhibitors of human carbonic anhydrase-II

Human carbonic anhydrases (hCAs) play a central role in various physiological processes in the human body. HCAs catalyze the reversible hydration of CO2 into HCO3−, and hence maintains the fluid and pH balance. Overexpression of CA II is associated with diseases, such as glaucoma, and epilepsy. Therefore, CAs are important clinical targets and inhibition of different isoforms, especially hCA II is used in treatment of glaucoma, altitude sickness, and epilepsy. Therapeutically used CA inhibitors (CAI) are sulfonamide-based, such as acetazolamide, dichlorphenamide, methazolamide, ethoxzolamide, etc. However, they exhibit several undesirable effects such as numbness, tingling of extremities, malaise, metallic taste, fatigue, renal calculi, and metabolic acidosis. Therefore, there is an urgent need to identify safe and effective inhibitors of the hCAs. In this study, different phenyl boronic acids 1–5 were evaluated against bovine (bCA II) and hCA II. Among all, compound 1 (4-acetylphenyl boronic acid) was found to be active against bCAII and hCA II with IC50 values of 246 ± 0.48 and 281.40 ± 2.8 μM, respectively, while the remaining compounds were found in-active. Compound 1 was identified as competitive inhibitor of hCA II enzyme (Ki = 283.7 ± 0.002 μM). Additionally, compound 1 was found to be non-toxic against BJ Human fibroblast cell line. The X-ray crystal structure for hCA II in-complex with compound 1 was evaluated to a resolution of 2.6 Å. In fact, this the first structural analysis of a phenyl boron-based inhibitor bound to hCA II, allowing an additional structure-activity analysis of the compounds. Compound 1 was found to be directly bound in the active site of hCA II by interacting with His94, His119, and Thr199 residues. In addition, a bond of 3.11 Å between the zinc ion and coordinated boron atom of the boronic acid moiety of compound 1 was also observed, contributing to binding affinity of compound 1 for hCA II. PDB ID8IGF.

Novel 1,2,4-triazoles as selective carbonic anhydrase inhibitors showing ancillary anticathepsin B activity.

Background: Exploration of the multi-target approach considering both human carbonic anhydrase (hCA) IX and XII and cathepsin B is a promising strategy to target cancer. Methodology & Results:22novel 1,2,4-triazole derivatives were synthesized and evaluated for their inhibition efficacy against hCA I, II, IX,XII isoforms and cathepsin B. The compounds demonstrated effective inhibition against hCA IX and/or XII isoforms with considerable selectivity over off-targethCA I/II. All compounds presented significant anticathepsin B activities at a low concentration of 10-7M and in vitro results were also supported by themolecular modelingstudies. Conclusion: Insights of present study can be utilized in the rational design of effective and selective hCA IX and XII inhibitors capable of inhibiting cathepsin B.

Design and Synthesis of Novel N-Benzylidene Derivatives of 3-Amino-4-imino-3,5-dihydro-4H-chromeno[2,3-d]pyrimidine under Microwave, In Silico ADME Predictions, In Vitro Antitumoral Activities and In Vivo Toxicity.

The synthesis of a series of new N-benzylidene derivatives of 3-amino-4-imino-3,5-dihydro-4H-chromeno[2,3-d]pyrimidine 10(a-l) bearing two points of molecular diversity is reported. These new compounds were synthesized in five steps including two steps under microwave dielectric heating. They were fully characterized using 1H and 13C NMR, FTIR and HRMS. The in silico physicochemical properties of compounds 10(a-l) were determined according to Lipinski's rules of five (RO5) associated with the prediction of their bioavailability. These new compounds 10(a-l) were tested for their antiproliferative activities in fibroblasts and eight representative human tumoral cell lines (Huh7 D12, Caco2, MDA-MB231, MDA-MB468, HCT116, PC3, MCF7 and PANC1). Among them, the compounds 10h and 10i showed sub-micromolar cytotoxic activity on tumor cell lines (0.23 < IC50 < 0.3 μM) and no toxicity on fibroblasts (IC50 > 25 μM). A dose-dependent inhibition of Store-Operated Ca+2 Entry (SOCE) was observed in the HEK293 cell line with 10h. In vitro embryotoxicity and angiogenesis on the mCherry transgenic zebrafish line showed that 10h presented no toxic effect and no angiogenic effect on embryos with a dose of 5 μM at 72 hpf.

The Effect of Chronic Levetiracetam Use on Erythrocyte Deformability

ABSTRACT Background: The inhibition of carbonic anhydrase (CA) isoenzymes is one of the targets in the development of new antiepileptics. Levetiracetam (LEV) is a new-generation antiepileptic drug frequently used in pediatric patients. It has a strong inhibitory effect on CA enzymes in many tissues, including erythrocytes. Objective: Due to CA enzymes have physical connection with the erythrocyte membrane and cytoskeleton, we aimed to evaluate the probable effect of LEV on the erythrocyte deformability. Materials and Methods: This study was conducted in the Experimental Animal Laboratory of Ankara Training and Research Hospital 24 prepubertal female Wistar albino rats were divided into four groups with six animals in each group. Group I: Control (distilled water), Group II: LEV50 (50 mg/kg/day), Group III: LEV150 (150 mg/kg/day), Group IV: LEV300 (300 mg/kg/day). The calculated dose for each animal was given by oral gavage once a day for 14 days, which is accepted as chronic use in experimental models. At the end of the treatment period, erythrocyte deformability was evaluated both with whole blood viscosity at high shear rates, and osmotic fragility test. Results: No statistically significant difference was found between the groups in terms of osmotic fragility. Whole blood and plasma viscosity values also did not show any statistically significant difference between the groups. Conclusion: In this study, it has been shown that LEV does not have a negative effect on erythrocyte deformability. Therefore, we thought that it may be a good choice when an antiepileptic is needed in pediatric patients with hematological disorders.

Synthesis, molecular docking analysis, drug-likeness evaluation, and inhibition potency of new pyrazole-3,4-dicarboxamides incorporating sulfonamide moiety as carbonic anhydrase inhibitors.

A series of novel pyrazole-dicarboxamides were synthesized from pyrazole-3,4-dicarboxylic acid chloride and various primary and secondary sulfonamides. The structures of the new compounds were confirmed by FT-IR, 1H-NMR, 13C-NMR, and HRMS. Then the inhibition effects of newly synthesized molecules on human erythrocyte hCA I and hCA II isoenzymes were investigated. Ki values of the compounds were in the range of 0.024-0.496 µM for hCA I and 0.006-5.441 µM for hCA II. Compounds 7a and 7i showed nanomolar level of inhibition of hCA II, and these compounds exhibited high selectivity for this isoenzyme. Molecular docking studies were performed between the most active compounds 7a, 7b, 7i, and the reference inhibitor AAZ and the hCAI and hCAII to investigate the binding mechanisms between the compounds and the isozymes. These compounds showed better interactions than the AAZ. ADMET and drug-likeness analyses for the compounds have shown that the compounds can be used pharmacologically in living organisms.

Polmacoxib: A Review of the Newer Non-steroidal Anti-inflammatory Drug in Osteoarthritis.

Osteoarthritis represents a huge socioeconomic burden and has a significant impact on daily life and productivity. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used in the management of osteoarthritis to curbinflammation, pain, and stiffness and improve physical function. However, due to the various side effects, most healthcare professionals avoid using NSAIDs for a long period. Nonselective cyclooxygenase (COX) inhibitors and cyclooxygenase-1 (COX-1) inhibitors are associated with increased gastrointestinal adverse effects due to the inhibition of prostaglandins, which are responsible for protecting the gastric mucosa. Cyclooxygenase-2 (COX-2) inhibitors are associated with an increased incidence of adverse cardiovascular effects due to their COX-2 inhibitory activity in the circulatory system. Therefore, there is a need for a newer NSAID that has a better safety profile to be used in osteoarthritis. Polmacoxib is a new, orally active, first-in-class NSAID that is a dual inhibitor of COX-2 and carbonic anhydrase (CA). The dual mode of action exhibited by polmacoxib is expected to minimize adverse cardiovascular effects while achieving maximum effectiveness in inflamed osteoarthritic joints. This article aims toreview the pharmacological properties, clinical efficacy, and safety data of polmacoxib in osteoarthritis.

Inhibitor binding to metal-substituted metalloenzyme: Sulfonamide affinity for carbonic anhydrase IX

Transition metal ions are structural and catalytic cofactors of many proteins including human carbonic anhydrase (CA), a Zn-dependent hydrolase. Sulfonamide inhibitors of CA recognize and form a coordination bond with the Zn ion located in the active site of the enzyme. The Zn ion may be removed or substituted with other metal ions. Such CA protein retains the structure and could serve as a tool to study metal ion role in the recognition and binding affinity of inhibitor molecules. We measured the affinities of selected divalent transition metal ions, including Mn, Fe, Co, Ni, Cu, Cd, Hg, and Zn to metal-free CA isozymes CA I, CA II, and CAIX by fluorescence-based thermal shift assay, prepared metal-substituted CAs, and determined binding of diverse sulfonamide compounds.Sulfonamide inhibitor binding to metal substituted CA followed a U-shape pH dependence. The binding was dissected to contributing binding-linked reactions and the intrinsic binding reaction affinity was calculated. This value is independent of pH and protonation reactions that occur simultaneously upon binding native CA and as demonstrated here, to metal substituted CA. Sulfonamide inhibitor binding to cancer-associated isozyme CAIX diminished in the order: Zn > Co > Hg > Cu > Cd > Mn > Ni. Energetic contribution of the inhibitor-metal coordination bond was determined for all above metals. The understanding of the principles of metal influence on ligand affinity and selectivity should help design new drugs targeting metalloenzymes.

Efficient activation of peroxymonosulfate by Co/Cu co-substituted-ferrite and carbon composite for rapid degradation of tetracycline in aqueous phase: Performance evaluation and mechanisms

In this study, a novel Co/Cu co-substituted ferrite-carbon composite CoxCu1-xFe2O4@C (x = 0.1, 0.3, 0.5, 0.7, and 0.9) was prepared by gel-thermolysis to activate peroxymonosulfate (PMS) for tetracycline (TC) removal. The materials were comprehensively characterized using different instruments. Batch experiments were conducted to investigate the effects of different operating parameters on TC removal. Our findings indicated that appropriate amount of Co and Cu substitution was very important. Co0.5Cu0.5Fe2O4@C (CoCF-0.5@C) exhibited the best activity. Using 0.1 g/LCoCF-0.5@C and 0.15 g/LPMS achieved 90.06 % TC removal (0.4091 min−1) in 6 min. Humic acid significantly inhibited TC removal, whereas the impact of coexisting anions varied. Thereinto, CO32− displayed moderate inhibitory effect, Ca2+ and NH4+ showed weak inhibitory effect, and SO42− exhibited insignificant effect. CoCF-0.5@C demonstrated not only excellent activity but also remarkable stability and anti-interference ability, achieving over 60 % TC removal under diverse conditions, such as a wide pH range (pH 3–11), different coexisting ions, and various matrices. Even after 5 cycles, CoCF-0.5@C could maintain 78.4 % TC removal. Compared to other catalysts in previous studies, CoCF-0.5@C combines the dual advantages of high activity and reproducibility. The results of quenching experiments, EPR/ESR and electrochemical tests showed that TC removal mechanism were dominated by non-radical 1O2 and direct electron transfer. The cycling of Cu2+/Cu+, Fe3+/Fe2+, and Co3+/Co2+ in CoCF-0.5@C played a pivotal role in PMS activation, accelerating electron transfer and reactive oxygen species (ROS) generation. The carbon helped to disperse ferrite and avoid its agglomeration, which significantly enhanced electron transfer. Based on the degradation products of TC, two possible pathways for TC degradation were proposed. This study provides a new approach for development of efficient PMS activators to promote TC degradation.

Hypoxia-activated and improved cell uptake near-infrared fluorescent probe for precise guiding surgical resection

Tumor imaging and fluorescence-guided surgical resection offers a promising therapeutic approach for the treatment of cancer with simple operation. Hypoxia, as a crucial feature in solid tumor, is closely related to the design of hypoxia-activated fluorescent probes to distinguish tumor and normal tissue. In present, many hypoxia-activated fluorescent probes have received widespread attention in various imaging applications. However, as far as we know, hypoxia-activated near-infrared fluorescent probe for tumor fluorescence-guided surgical resection is not currently reported. Therefore, a hypoxia-activated near-infrared fluorescent probes Fu-Cy was synthesized. It was able to produce near-infrared fluorescence (780 nm) in specific response to overexpressed nitroreductase in hypoxic tumors with rapid response. However, the uptake of the probe in the cell will affect the imaging ability of the probe. Therefore, acetazolamide (AZ), a well-known inhibitor of carbonic anhydrase IX (CAIX), was coupled to Fu-Cy by clicking reaction to obtain the improved probe Az-Fu-Cy, which is more absorbed by cancer cells than Fu-Cy. Thus, Az-Fu-Cy can effectively distinguish between tumors and normal organs by spraying. Interestingly, it showed accurate guidance during surgical resection.

Exploring Novel Schiff Base Compounds Derived from Benzothiophene-3- carboxaldehyde Hydrazones: In vitro and In silico Evaluation as Potential Inhibitors of Cholinesterases and Carbonic Anhydrases I-II

In this study, inhibitions of some cytosolic enzymes were evaluated. Inhibitors of these enzymes can help illuminate and treat many related diseases (Alzhaimer, Parkinson's, Glaucoma, etc.). It is aimed to minimize drug side effects with multiple effects in one molecule. For this purpose in vitro effects of two benzothiophene Schiff bases on cholinesterases (AChE and BuChE) and human carbonic anhydrase isoforms (CAI and CAII) were investigated. Molecular modeling studies were carried out to elucidate the inhibition mechanism of two effective compounds on these enzymes. Then, two benzothiophene Schiff bases (1a and 1b compounds) were tested in vitro on these enzymes. The in vitro study results supported the in silico study results. Obtained results revealed that the benzothiophene derivatives inhibited the enzymes significantly. Ki values for CAI isoenzyme were determined to be in the range of 58.82 ± 7.96-126.28 ± 26.22 nM; for the CAII isoenzyme in the range of 27.86 ± 3.76-74.30 ± 7.89 nM; for acetylcholinesterase in the range of 1.31 ± 0.39-2.16 ± 1.01 nM; for butyrylcholinesterase in the range of 1.80 ± 0.27-2.01 ± 1.67 nM. Compared to the AZA control compound, 1b has demonstrated more strong inhibitory effect against CAI and CAII. Wherease compared with other control compound Tacrine, both compounds showed more potent inhibitory effect for cholinesterases (AChE and BuChE).

Acetazolamide as an effective treatment for pilomotor seizures in autoimmune encephalitis.

Pilomotor seizures are strongly associated with autoimmune encephalitis (AE), particularly anti-LGI1 encephalitis. The carbonic anhydrase inhibitor acetazolamide may have special efficacy for treating AE-associated pilomotor seizures. Six patients with AE (five anti-LGI1, one seronegative) and temporal lobe pilomotor seizures (five with seizures inducible by hyperventilation) were treated with acetazolamide, administered in a cycling (2-days-ON, 4-days-OFF) regimen to offset tolerance. Seizures were assessed during epilepsy monitoring unit (EMU) recordings in four inpatients (one of whom also maintained an outpatient seizure diary chronicling 1203 seizures over 1079 days); two outpatients self-reported seizure frequencies. The extended diary revealed an inverse correlation between acetazolamide and proportion of seizures/day: 6%, 2% (days 1, 2 ON); 3%, 13%, 31%, 45% (days 1, 2, 3, 4 OFF). This patient later developed focal status epilepticus upon wean of antiseizure medications during a seropositive AE relapse that was remarkably aborted with acetazolamide monotherapy. The other three EMU patients averaged .56 seizures/day ON, and 3.81 seizures/day OFF (p = .004). The two outpatients reported seizure reductions from 3-5/day to 2/week, and 15-20/day to none, respectively, after initiation of cycling acetazolamide. Likely related to cerebral CO2/pH sensitivity, acetazolamide can be unusually effective in controlling pilomotor seizures in AE, chronically or in acute settings.

Identification of Ureidocoumarin-Based Selective Discoidin Domain Receptor 1 (DDR1) Inhibitors via Drug Repurposing Approach, Biological Evaluation, and In Silico Studies.

Discoidin domain receptor 1 (DDR1) kinase has emerged as a promising target for cancer therapy, and selective DDR1 inhibitors have shown promise as effective therapeutic candidates. Herein, we have identified the first coumarin-based selective DDR1 inhibitors via repurposing of a recent series of carbonic anhydrase inhibitors. Among these, ureidocoumarins 3a, 3i, and 3q showed the best DDR1 inhibitory activities. The m-trifluoromethoxy phenyl member 3q potently inhibited DDR1 with an IC50 of 191 nM, while it showed less inhibitory activity against DDR2 (IC50 = 5080 nM). 3q also exhibited favorable selectivity in a screening platform with 23 common off-target kinases, including BCR-ABL. In the cellular context, 3q showed moderate antiproliferative effects, while 3i, with the third rank in DDR1 inhibition, exerted the best anticancer activity with sub-micromolar GI50 values over certain DDR1-dependent cell lines. Molecular docking and MD simulations disclosed the putative binding mode of this coumarin chemotype and provided insights for further optimization of this scaffold. The present findings collectively supported the potential improvement of ureidocoumarins 3i and 3q for cancer treatment.

Combining BNCT with carbonic anhydrase inhibition for mesothelioma treatment: Synthesis, in vitro, in vivo studies of ureidosulfamido carboranes

Mesothelioma is a malignant neoplasm of mesothelial cells caused by exposure to asbestos. The average survival time after diagnosis is usually nine/twelve months. A multi-therapeutic approach is therefore required to treat and prevent recurrence. Boronated derivatives containing a carborane cage, a sulfamido group and an ureido functionality (CA-USF) have been designed, synthesised and tested, in order to couple Boron Neutron Capture Therapy (BNCT) and the inhibition of Carbonic Anhydrases (CAs), which are overexpressed in many tumours. In vitro studies showed greater inhibition than the reference drug acetazolamide (AZ). To increase solubility in aqueous media, CA-USFs were used as inclusion complexes of hydroxypropyl β-cyclodextrin (HP-β-CD) in all the inhibition and cell experiments. BNCT experiments carried out on AB22 (murine mesothelioma) cell lines showed a marked inhibition of cell proliferation by CA-USFs, and in one case a complete inhibition of proliferation twenty days after neutron irradiation. Finally, in vivo neutron irradiation experiments on a mouse model of mesothelioma demonstrated the efficiency of combining CA IX inhibition and BNCT treatment. Indeed, a greater reduction in tumour mass was observed in treated mice compared to untreated mice, with a significant higher effect when combined with BNCT. For in vivo experiments CA-USFs were administered as inclusion complexes of higher molecular weight β-CD polymers thus increasing the selective extravasation into tumour tissue and reducing clearance. In this way, boron uptake was maximised and CA-USFs demonstrated to be in vivo well tolerated at a therapeutic dose. The therapeutic strategy herein described could be expanded to other cancers with increased CA IX activity, such as melanoma, glioma, and breast cancer.

Профилактический эффект ингибитора карбоангидразы на повышение внутриглазного давления после интравитреальных инъекций анти-VEGF препарата

Purpose. To evaluate the effect of a carbonic anhydrase inhibitor (brinzolamide 1%) on the short-term increase of intraocular pressure (IOP) after intravitreal injections (IVI) of an anti-VEGF drug in patients with neovascular AMD (nAMD). Material and methods. This study included 60 patients with newly diagnosed nAMD. In group 1 (30 people), prophylactic drugs were not used; in group 2 (30 people), brinzolamide 1% was instilled twice the day before the injection (at 8 pm) and on the day of injection 2 hours before the procedure (at 8 am). IOP was measured with an ICare Pro before IVI (T0), 1 minute after IVI (T₁), 30 minutes (T₂), 60 minutes (T₃). Results. Dynamic changes of IOP in all groups occurred with the same pattern: IOP increased immediately after IVI of the anti-VEGF drug, after 30 minutes IOP decreased and returned to the initial IOP level over the next 60 minutes. Brinzolamide 1% led to a statistically significant decrease in IOP immediately after injection during the first IVI by an average of 3.84 ± 5.1 [95 % CI 1.58–6.1] mm Hg. compared with the control group (p &lt; 0.001), during the second IVI by 5.26 ± 5.7 [95 % CI 2.86–7.66] mm Hg (p &lt; 0.001), by 5.49 ± 5.8 [95 % CI 3.1–7.88] mm Hg (p &lt; 0.001) during the third IVI. Conclusions. Prophylactic instillation of carbonic anhydrase inhibitor (brinzolamide 1%) twice led to a statistically significant decrease in ocular hypertension immediately after IVI of anti-VEGF drug compared to the control group over three loading injections. Keywords: anti-VEGF drug, intraocular pressure, carbonic anhydrase inhibitor

Sulfonamide-incorporated bis(α-aminophosphonates) as promising carbonic anhydrase inhibitors: Design, synthesis, biological evaluation, and X-ray crystallographic studies.

A novel series of sulfonamide-incorporated bis(α-aminophosphonates) acting as effective carbonic anhydrase (CA, EC 4.2.1.1) inhibitors is reported. The synthesized bivalent ligands were tested against five human (h) isoforms, hCA I, hCA II, hCA VII, hCA IX, and hCA XIII. Such derivatives showed high activity and selectivity against the cancer-related, membrane-bound isoform hCA IX, and among them, compound 5h, tetraisopropyl (1,3-phenylenebis{[(4-sulfamoylphenyl)amino]methylene})bis(phosphonate)showed a KI of 15.1 nM, being highly selective against this isoform over all other investigated ones (hCA I/IX = 42; hCA II/IX = 6, hCA VII/IX = 3, hCA XIII/IX = 5). Therefore, compound 5h could be a potential lead for the development of selective anticancer agents. The newly developed sulfonamides were also found effective inhibitors against the cytosolic hCA XIII isoform. Compound 5i displayed the best inhibition against this isoform with a KI of 17.2 nM, equal to that of the well-known inhibitor acetazolamide (AAZ), but significantly more selective over all other tested isoforms (hCA I/XIII = 239; hCA II/XIII = 23, hCA VII/XIII = 2, hCA IX/XIII = 3) compared to AAZ.

Exploring rhodanine linked enamine-carbohydrazide derivatives as mycobacterial carbonic anhydrase inhibitors: Design, synthesis, biological evaluation, and molecular docking studies.

With the rise of multidrug-resistant tuberculosis, the imperative for an alternative and superior treatment regimen, incorporating novel mechanisms of action, has become crucial. In pursuit of this goal, we have developed and synthesized a new series of rhodanine-linked enamine-carbohydrazide derivatives, exploring their potential as inhibitors of mycobacterial carbonic anhydrase. The findings reveal their efficacy, displaying notable selectivity toward the mycobacterial carbonic anhydrase 2 (mtCA 2) enzyme. While exhibiting moderate activity against human carbonic anhydrase isoforms, this series demonstrates promising selectivity, positioning these compounds as potential antitubercular agents. Compound 6d was the best one from the series with a Ki value of 9.5 µM toward mtCA 2. Most of the compounds displayed moderate to good inhibition against the Mtb H37Rv strain; compound 11k showed a minimum inhibitory concentration of 1 µg/mL. Molecular docking studies revealed that compounds 6d and 11k show metal coordination with the zinc ion, like classical CA inhibitors.

New N-(1,3,4-thiadiazole-2-yl)acetamide derivatives as human carbonic anhydrase I and II and acetylcholinesterase inhibitors

Various carbonic anhydrase (CA) enzyme isoforms are known today. In addition to the use of CA inhibitors as diuretics, antiepileptics and antiglaucoma agents, the inhibition of other specific isoforms of CA was reported to have clinical benefits in cancers. In this study, two groups of 1,3,4-thiadiazole derivatives were designed and synthesized to act as human CA I and II (hCA I and hCA II) inhibitors. The activities of these compounds were tested in vitro and evaluated in silico studies. The activity of the synthesized compounds was also tested against acetylcholinesterase (AChE) to evaluate the relation of the newly designed structures to the activity against AChE. The synthesized compounds were analyzed by 1H NMR,13C NMR and high-resolution mass spectroscopy (HRMS). The results displayed a better activity of all the synthesized compounds against hCA I than that of the commonly used standard drug, Acetazolamide (AAZ). The compounds also showed better activity against hCA II, except for compounds 5b and 6b. Only compounds 6a and 6c showed superior activity against AChE compared to the standard agent, tacrine (THA). In silico studies, including absorption, distribution, metabolism and excretion (ADME) and drug-likeness evaluation, molecular docking, molecular dynamic simulations (MDSs) and density functional theory (DFT) calculations, were compatible with the in vitro results and presented details regarding the structure–activity relationship. Communicated by Ramaswamy H. Sarma

Novel Anthraquinone-Based Benzenesulfonamide Derivatives and Their Analogues as Potent Human Carbonic Anhydrase Inhibitors with Antitumor Activity: Synthesis, Biological Evaluation, and In Silico Analysis.

In this study, we designed two series of novel anthraquinone-based benzenesulfonamide derivatives and their analogues as potential carbonic anhydrase inhibitors (CAIs) and evaluated their inhibitory activities against off-target human carbonic anhydrase II (hCA II) isoform and tumor-associated human carbonic anhydrase IX (hCA IX) isoform. Most of these compounds exhibited good inhibitory activities against hCA II and IX. The compounds that exhibited the best hCA inhibition were further studied against the MDA-MB-231, MCF-7, and HepG2 cell lines under hypoxic and normoxic conditions. Additionally, the compounds exhibiting the best antitumor activity were subjected to apoptosis and mitochondrial membrane potential assays, which revealed a significant increase in the percentage of apoptotic cells and a notable decrease in cell viability. Molecular docking studies were performed to demonstrate the presence of numerous hydrogen bonds and hydrophobic interactions between the compounds and the active site of hCA. Absorption, distribution, metabolism, excretion (ADME) predictions showed that all of the compounds had good pharmacokinetic and physicochemical properties.