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1.
Bioorg Chem ; 147: 107366, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38636435

RESUMEN

α-Glycosidase inhibition is one of the main approaches to treat Diabetes mellitus. Polyphenolic moieties are known to be responsible for yielding exhibit potent α-glycosidase inhibitory effects. In addition, compounds containing benzothiazole and Schiff base functionalities were previously reported to show α-glycosidase inhibition. In this paper, the synthesis of seven new phloroglucinol-containing benzothiazole Schiff base derivatives through the reaction of 6-substituted-2-aminobenzothiazole compounds with 2,4,6-trihydroxybenzaldehyde using acetic acid as a catalyst was reported. The synthesized compounds were characterized using spectroscopic methods such as FT-IR, 1H NMR, 13C NMR, and elemental analysis. The synthesized compounds were evaluated for their inhibitory effects on α-glycosidase, compounds 3f and 3g were found to show significant inhibitory properties when compared to the positive control. The IC50 values of 3f and 3g were calculated as 24.05 ± 2.28 and 18.51 ± 1.19 µM, respectively. Kinetic studies revealed that compounds 3f and 3g exhibited uncompetitive mode of inhibition against α-glycosidase. Molecular modeling predicted druglikeness for the title compounds and underpinned the importance of phloroglucinol hydroxyls for interacting with the key residues of α-glycosidase.


Asunto(s)
Benzotiazoles , Inhibidores Enzimáticos , Polifenoles , Benzotiazoles/química , Benzotiazoles/farmacología , Benzotiazoles/síntesis química , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Polifenoles/química , Polifenoles/farmacología , Polifenoles/síntesis química , Relación Estructura-Actividad , Estructura Molecular , Glicósido Hidrolasas/antagonistas & inhibidores , Glicósido Hidrolasas/metabolismo , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/síntesis química , Simulación del Acoplamiento Molecular , Humanos , Relación Dosis-Respuesta a Droga , alfa-Glucosidasas/metabolismo , Cinética
2.
Chem Biodivers ; : e202401386, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39031506

RESUMEN

Various Vinca species have been traditionally used for their antihypertensive, sedative, and hemostatic properties, as well as for treating diabetes. In this study, some flavonoids, phenolic acids and iridoids were isolated from an endemic Vinca species, Vinca soneri for the first time. α-Glucosidase inhibitory effects of the isolates were tested and kaempferol-3-O-α-rhamnopyranosyl (1→6) ß-galactopyranoside (1) was found to be the most active one with an IC50 value of 285.73 ± 7.35 µM. Enzyme kinetic assay revealed that it inhibited α-glucosidase in competitive manner. Molecular geometry of 1 was predicted and Frontier molecular orbital analysis was performed using Density Functional Theory (DFT) calculations. Molecular docking and MM-GBSA calculations predicted good fit for 1 in the enzyme active site and key interactions with the catalytic residues. As a result, current study identifies 1 as a promising competitive α-glucosidase inhibitor to be developed as a potential antidiabetic drug candidate.

3.
Drug Dev Res ; 85(3): e22184, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38634273

RESUMEN

Alzheimer's disease (AD), one of the main causes of dementia, is a neurodegenerative disorder. Cholinesterase inhibitors are used in the treatment of AD, but prolonged use of these drugs can lead to serious side effects. Drug repurposing is an approach that aims to reveal the effectiveness of drugs in different diseases beyond their clinical uses. In this work, we investigated in vitro and in silico inhibitory effects of 11 different drugs on cholinesterases. The results showed that trimebutine, theophylline, and levamisole had the highest acetylcholinesterase inhibitory actions among the tested drugs, and these drugs inhibited by 68.70 ± 0.46, 53.25 ± 3.40, and 44.03 ± 1.20%, respectively at 1000 µM. In addition, these drugs are bound to acetylcholinesterase via competitive manner. Molecular modeling predicted good fitness in acetylcholinesterase active site for these drugs and possible central nervous system action for trimebutine. All of these results demonstrated that trimebutine was determined to be the drug with the highest potential for use in AD.


Asunto(s)
Enfermedad de Alzheimer , Trimebutino , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Acetilcolinesterasa/metabolismo , Trimebutino/uso terapéutico , Inhibidores de la Colinesterasa/química , Modelos Moleculares , Simulación del Acoplamiento Molecular
4.
Chem Biodivers ; 20(11): e202301003, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37819048

RESUMEN

In this work, the phytochemical characterization, biological activity, and cytotoxic mechanism of aerial and rhizome methanol extracts (SME and RME) of Epimedium pubigerum were investigated to demonstrate its potential usage in the treatment of lung cancer. LC-HRMS analysis, total phenolic/flavonoid content assay, DPPH radical scavenging assay, DNA interaction, cytotoxicity, and western blotting were investigated using different methods. Fumaric acid was found to be the most abundant compound in both extracts. SME and RME were cytotoxic on A549 cells concentration-dependently. Also, in vitro scratch assay showed that SME and RME led to a significant anti-migratory effect at 1 mg/mL. Cytochrome c, p53, and caspase 3 expression significantly increased in the presence of RME compared to the control. All of these results claimed that RME might be suggested as a theoretically more effective phytotherapeutic agent for lung cancer compared to the effect seen with the SME.


Asunto(s)
Antineoplásicos , Epimedium , Neoplasias Pulmonares , Humanos , Antioxidantes/química , Extractos Vegetales/química , Neoplasias Pulmonares/tratamiento farmacológico
5.
Drug Dev Res ; 84(5): 1018-1028, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37154110

RESUMEN

Azoles, which have been used for antifungal chemotherapy for decades, have recently been of interest for their efficacy against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). There is little known about the potential of azoles against BChE, however there is none regarding their inhibitory effects against mutants of BChE. In the current study, an azole library of 1-aryl-2-(1H-imidazol-1-yl)ethanol/ethanone oxime esters were tested against AChE and BChE, which yielded derivates more potent than the positive control, galantamine, against both isoforms. Kinetic analyses were performed for wildtype and mutant (A328F and A328Y) inhibition for the two most potent BChE inhibitors, pivalic and 3-bezoylpropanoic acid esters of 2-(1H-imidazol-1-yl)-1-(2-naphthyl)ethanol, which were found to have great affinity to the wildtype and mutant BChE types with Ki values as low as 0.173 ± 0.012 µM. The compounds were identified to show linear competitive or mixed type inhibition. Molecular modeling confirmed these kinetic data and provided further insights regarding molecular basis of BChE inhibition by the active derivatives. Thus, current study suggests new azole derivatives with promising cholinesterase inhibitory effects and reveals the first set of information to promote our understanding for the inhibitory behavior of this class against the mutant BChE forms.


Asunto(s)
Acetilcolinesterasa , Butirilcolinesterasa , Butirilcolinesterasa/genética , Butirilcolinesterasa/metabolismo , Acetilcolinesterasa/genética , Acetilcolinesterasa/metabolismo , Azoles/farmacología , Inhibidores de la Colinesterasa/farmacología , Ésteres , Simulación del Acoplamiento Molecular , Relación Estructura-Actividad
6.
Chem Biodivers ; 19(10): e202200352, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36149030

RESUMEN

Polydatin or piceid, is the 3-O-glucoside of resveratrol and is found abundantly in grapes, peanuts, wine, beer, and cacao products. Although anticancer activity of polydatin was reported before, and potential antiproliferative mechanisms of polydatin have been proposed, its direct effects on DNA and inhibitory potential against topoisomerase enzymes have remained unknown. In this study we aimed to reveal the link between polydatin's effects on DNA and DNA-topoisomerases and its antiproliferative promise. For this purpose, we evaluated the effects of polydatin on DNA and DNA topoisomerase using in vitro and in silico techniques. Polydatin was found to protect DNA against Fenton reaction-induced damage while not showing any hydrolytic nuclease effect. Further, polydatin inhibited topoisomerase II but not topoisomerase I. According to molecular docking studies, polydatin preferably showed minor groove binding to DNA where the stilbene moiety was important for binding to the DNA-topoisomerase II complex. As a result, topoisomerase II inhibition might be another anticancer mechanism of polydatin.


Asunto(s)
Estilbenos , Resveratrol , Simulación del Acoplamiento Molecular , Estilbenos/farmacología , Estilbenos/química , Glucósidos/farmacología , ADN-Topoisomerasas de Tipo II , ADN/metabolismo
7.
Chem Biodivers ; 19(7): e202200027, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35695705

RESUMEN

Cholinesterase inhibition is of great importance in the fight against neurodegenerative disorders such as Alzheimer's disease. Azole antifungals have come under the spotlight with recent discoveries that underline the efficacy and potential of miconazole and its derivatives against cholinesterase enzymes. In this study, we evaluated a library of azoles against acetylcholinesterase and butyrylcholinesterase using in vitro and in silico methods to identify potent inhibitors. Low micromolar IC50 values were obtained for imidazole derivatives, which were further tested and found potent competitive cholinesterase inhibitors via enzyme kinetics study. The active derivatives showed negligible toxicity in in vitro cytotoxicity tests. Molecular modeling studies predicted that these derivatives were druglike, could penetrate blood-brain barrier, and tightly bind to cholinesterase active site making key interactions via the imidazole moiety at protonated state. Thus, current study identifies potent and competitive cholinesterase inhibitor azoles with minor toxicity and potential to pass into the central nervous system.


Asunto(s)
Enfermedad de Alzheimer , Inhibidores de la Colinesterasa , Acetilcolinesterasa/metabolismo , Antifúngicos/farmacología , Azoles/farmacología , Butirilcolinesterasa/metabolismo , Sistema Nervioso Central , Inhibidores de la Colinesterasa/química , Humanos , Imidazoles , Simulación del Acoplamiento Molecular , Naftalenos , Relación Estructura-Actividad
8.
Drug Dev Res ; 83(1): 184-193, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34291476

RESUMEN

Nafimidone is known for its clinical antiepileptic effects and alcohol derivatives of nafimidone were reported be potent anticonvulsants. These compounds are structurally similar to miconazole, which is known to inhibit cholinesterases, protect neurons, and ameliorate cognitive decline. Herein, we aimed to reveal the potential of three nafimidone alcohol esters (5 g, 5i, and 5 k), which were previously reported for their anticonvulsant effects, against co-morbidities of epilepsy such as inflammatory and neuropathic pain, cognitive and behavioral deficits, and neuron death, and understand their roles in related pathways such as γ-butyric acid type A (GABAA ) receptor and cholinesterases using in vitro, in vivo and in silico methods. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test was used for cytotoxicity evaluation, hippocampal slice culture assay for neuroprotection, formalin test for acute and inflammatory pain, sciatic ligation for neuropathic pain, Morris water maze and open field locomotor tasks for cognitive and behavioral deficits, radioligand binding for GABAA receptor affinity, spectrophotometric methods for cholinesterase inhibition in vitro, and molecular docking in silico. The compounds were non-toxic to fibroblast cells. 5 k was neuroprotective against kainic acid-induced neuron death. 5i reduced pain response of mice in both the acute and the inflammatory phases. 5i improved survival upon status epilepticus. The compounds showed no affinity to GABAA receptor but inhibited acetylcholinesterase, 5 k also inhibited butyrylcholinesterase. The compounds were predicted to interact mainly with the peripheric anionic site of cholinesterase enzymes. The title compounds showed neuroprotective, analgesic, and cholinesterase inhibitory effects, thus they bear promise against certain co-morbidities of epilepsy with neurological insults.


Asunto(s)
Butirilcolinesterasa , Epilepsia , Acetilcolinesterasa/metabolismo , Animales , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/uso terapéutico , Epilepsia/tratamiento farmacológico , Ratones , Simulación del Acoplamiento Molecular , Morbilidad , Nafazolina/análogos & derivados
9.
Bioorg Chem ; 107: 104637, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33454505

RESUMEN

Cancer has become an important public problem in worldwide since cancer incidence and mortality are growing rapidly. In this study, water soluble and non-aggregated silicon (IV) phthalocyanines and naphthalocyanines containing (3,5-bis{3-[3-(diethylamino)phenoxy]propoxy}phenyl)methoxy groups have been synthesized and characterized to investigate their anticancer potential. Their DNA binding/nuclease, topoisomerases inhibition were investigated using UV-Vis absorption, thermal denaturation and agarose gel electrophoresis. The in vitro cytotoxic properties of the compounds on human lung (A549), breast (BT-20), liver (SNU-398), prostate (DU-145), melanoma (SK-Mel 128) carcinoma and human fibroblast (HFC) normal cell lines were evaluated by using MTT assay. In order to determine the mechanism of cancer cell growth suppression, cell cycle analysis was carried out using flow cytometer on A549 cell line. The Kb values of SiPc1a and SiNc2a were 6.85 ± (0.35) × 106 and 1.72 ± (0.16) × 104 M-1 and Tm values of ct-DNA were calculated as 82.02 °C and 78.07 °C, respectively in the presence of both compounds. The ΔTm values of SiPc1a and SiNc2a were calculated as 6.45 and 2.50 °C, respectively. The nuclease effects of SiPc1a and SiNc2a with supercoiled plasmid pBR322 DNA demonstrated that both compounds did not trigger any DNA nuclease effects at the lowest concentrations without irradiation whereas both compounds in the presence of activating agent (H2O2) showed significant plasmid DNA nuclease actions under irradiation (22.5 J/cm2). SiPc1a and SiNc2a inhibited to topoisomerase I on increasing concentrations whilst they had lower inhibition action toward topoisomerase II that of topoisomerase I. The in vitro cytotoxicity studies displayed that SiPc1a had the highest cytotoxic effects among the tested compounds against A549, SNU-398, SK-MEL128, DU-145, BT-20 and HFC cell lines with CC50 values ranged from 0.49 to 2.99 µM. Furthermore, SiPc1a inhibited cell proliferation by cell cycle arrest in G0/G1 phase. All of these results suggested that SiPc1a is a promising candidate as an anticancer agent.


Asunto(s)
Antineoplásicos/síntesis química , Diseño de Fármacos , Indoles/química , Compuestos de Organosilicio/química , Inhibidores de Topoisomerasa I/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , ADN/química , ADN/metabolismo , ADN-Topoisomerasas de Tipo I/química , ADN-Topoisomerasas de Tipo I/metabolismo , ADN-Topoisomerasas de Tipo II/química , ADN-Topoisomerasas de Tipo II/metabolismo , Desoxirribonucleasas/antagonistas & inhibidores , Desoxirribonucleasas/metabolismo , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Humanos , Peróxido de Hidrógeno/farmacología , Indoles/metabolismo , Indoles/farmacología , Compuestos de Organosilicio/metabolismo , Compuestos de Organosilicio/farmacología , Solubilidad , Inhibidores de Topoisomerasa I/metabolismo , Inhibidores de Topoisomerasa I/farmacología , Agua/química
10.
Phytochem Anal ; 31(3): 314-321, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31997462

RESUMEN

INTRODUCTION: Tyrosinase is a multifunctional copper-containing oxidase enzyme that catalyses the first steps in the formation of melanin pigments. Identification of tyrosinase inhibitors is of value for applications in cosmetics, medicine and agriculture. OBJECTIVE: To develop an analytical method that allows identification of drug-like natural products that can be further developed as tyrosinase inhibitors. Results of in vitro and in silico studies will be compared in order to gain a deeper insight into the mechanism of action of enzyme inhibition. METHOD: Using an in vitro assay we tested tyrosinase inhibitor effects of five structurally related flavones, i.e. luteolin (1), eupafolin (2), genkwanin (3), nobiletin (4), and chrysosplenetin (5). The strongest inhibitors were further investigated in silico, using enzyme docking simulations. RESULTS: All compounds tested showed modest tyrosinase inhibitory effect compared to the positive control, kojic acid. The polymethoxy flavones 4 and 5 exhibited the strongest tyrosinase inhibitory effect with the half maximal inhibitory concentration (IC50 ) values of 131.92 ± 1.75 µM and 99.87 ± 2.38 µM respectively. According to kinetic analysis 2, 4 and 5 were competitive inhibitors, whereas 1 and 3 were non-competitive inhibitors of tyrosinase. Docking studies indicated that methoxy groups on 4 and 5 caused steric hindrance which prevented alternative binding modes in the tyrosinase; the methoxy groups on the B-ring of these flavones faced the catalytic site in the enzyme. CONCLUSIONS: The docking simulations nicely complemented the in vitro kinetic studies, opening the way for the development of predictive models for use in drug design.


Asunto(s)
Agaricales , Flavonas , Inhibidores Enzimáticos , Cinética , Simulación del Acoplamiento Molecular , Estructura Molecular , Monofenol Monooxigenasa , Relación Estructura-Actividad
11.
Bioorg Chem ; 86: 296-304, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30738329

RESUMEN

Bark of Quercus coccifera is widely used in folk medicine. We tested tyrosinase and α-glucosidase inhibitory effects of Q. coccifera bark extract and isolated compounds from it. The extract inhibited tyrosinase with an IC50 value of 75.13 ±â€¯0.44 µg/mL. Among the isolated compounds, polydatin (6) showed potent tyrosinase inhibition compared to the positive control, kojic acid, with an IC50 value of 4.05 ±â€¯0.30 µg/mL. The Q. coccifera extract also inhibited α-glucosidase significantly with an IC50 value of 3.26 ±â€¯0.08 µg/mL. (-)-8-Chlorocatechin (5) was the most potent isolate, also more potent than the positive control, acarbose, with an IC50 value of 43.60 ±â€¯0.67 µg/mL. According to the kinetic analysis, 6 was a noncompetitive and 5 was a competitive inhibitor of tyrosinase, and 5 was a noncompetitive α-glucosidase inhibitor. In the light of these findings, we performed in silico molecular docking studies for 5 and 6 with QM/MM optimizations to predict their tyrosinase inhibition mechanisms at molecular level and search for correlations with the in vitro results. We found that the ionized form of 5 (5i) showed higher affinity and more stable binding to tyrosinase catalytic site than its neutral form, while 6 bound to the predicted allosteric sites of the enzyme better than the catalytic site.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Glucósidos/farmacología , Simulación del Acoplamiento Molecular , Monofenol Monooxigenasa/antagonistas & inhibidores , Extractos Vegetales/farmacología , Estilbenos/farmacología , alfa-Glucosidasas/metabolismo , Agaricales/enzimología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Glucósidos/química , Glucósidos/aislamiento & purificación , Estructura Molecular , Monofenol Monooxigenasa/metabolismo , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Quercus/química , Saccharomyces cerevisiae/enzimología , Estilbenos/química , Estilbenos/aislamiento & purificación , Relación Estructura-Actividad
12.
Bioorg Chem ; 92: 103259, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31518762

RESUMEN

In the present study, we aimed to identify the tyrosinase enzyme inhibitory potential of Vinca major L. extract and its secondary metabolites. The extract possessed remarkable tyrosinase enzyme inhibitory effect with IC50 value of 20.39 ±â€¯0.44 µg/mL compared to the positive control, kojic acid (IC50 8.56 ±â€¯0.17 µg/mL). Compounds 1 and 5 were the most potent isolates with IC50 values of 32.41 ±â€¯0.99 and 31.34 ±â€¯0.75 µM, they were more potent than kojic acid (IC50: 60.25 ±â€¯0.54 µM). Compound 2 also exhibited remarkable tyrosinase inhibition with an IC50 value of 64.51 ±â€¯1.29 µM. An enzyme kinetics analysis revealed that 1 was a mixed-type, 2 and 5 were noncompetitive inhibitors. Using molecular docking, we predicted binding affinity and interactions of the compounds, which were in good alignment with a pharmacophore hypothesis generated out of a number of known tyrosinase inhibitors. The modelling studies underlined crucial interactions with the copper ions and residues around them such as Asn260, His263, and Met280.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Vinca/química , Agaricales/enzimología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Cinética , Modelos Moleculares , Estructura Molecular , Monofenol Monooxigenasa/metabolismo , Relación Estructura-Actividad , Vinca/metabolismo
13.
Support Care Cancer ; 27(11): 4273-4281, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30874926

RESUMEN

PURPOSE: The aim of the present study was to evaluate the potential uroprotective effect of pantoprazole (PPZ) in a mouse model of cyclophosphamide (CP)-induced hemorrhagic cystitis (HC) due to its antioxidant and anti-inflammatory properties. METHODS: Balb/c mice received a single intraperitoneal (i.p.) injection of CP (300 mg/kg) to induce HC. PPZ (20, 50, and 100 mg/kg/day;i.p.) was administered for 3 consecutive days before the induction of HC. Mesna (30 mg/kg;i.p.) was administered 20 min before, 4 and 8 h after CP injection to compare the protective effects of PPZ. After 24 h of HC induction, the bladders were removed for functional studies, biochemical analyses, and histopathological examination. RESULTS: In vitro contractility studies demonstrated that CP-induced HC decreased the responsiveness of detrusor muscle strips to acetylcholine (ACh), which was reversed by PPZ pretreatment at all doses tested. However, mesna treatment was not able to improve responsiveness to ACh. Biochemical analyses showed that CP caused significant elevation of malondialdehyde (MDA), reduction of total glutathione (GSH), and increment of proinflammatory cytokine tumor necrosis factor-alpha (TNF-α) level, which were measured in bladder homogenates. PPZ pretreatment at three doses found to be effective in reducing the CP-induced elevation of MDA and TNF-α levels. The highest dose of PPZ (100 mg/kg) caused a significant increase in GSH level. CP induced severe HC with marked bladder edema and histological disturbances which were partially abolished by PPZ pretreatment. CONCLUSIONS: Our results indicate that PPZ pretreatment could attenuate CP-induced HC by interfering with oxidative stress and modulating proinflammatory cytokines.


Asunto(s)
Ciclofosfamida/efectos adversos , Cistitis/inducido químicamente , Cistitis/tratamiento farmacológico , Inmunosupresores/efectos adversos , Pantoprazol/uso terapéutico , Inhibidores de la Bomba de Protones/uso terapéutico , Animales , Cistitis/patología , Modelos Animales de Enfermedad , Masculino , Ratones , Pantoprazol/farmacología , Inhibidores de la Bomba de Protones/farmacología
14.
Bioorg Chem ; 81: 168-174, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30130649

RESUMEN

Flavonoids are main polyphenolic groups widely distributed to fruits, vegetables and beverages we consumed daily. They exhibit many biological effects. We tested tyrosinase inhibitor potential of structurally related (1-9) flavonoids and found that all the tested materials possessed tyrosinase inhibitory effect compared to the positive control, kojic acid. 2 exhibited the strongest tyrosinase inhibitory effect with an IC50 value of 40.94 ±â€¯0.78 µM in a competitive manner. According to kinetic analysis 1, 4 and 7 were found to be competitive inhibitors, 3, 5, and 6 noncompetitive inhibitors of tyrosinase. According to the docking studies, A and C ring of the flavonoid structure, hydroxyl substituent at the 7th position, and hydroxyl substituents at para or para and meta position of ring B play key role for competitive inhibition of the enzyme.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Flavonoides/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Flavonoides/síntesis química , Flavonoides/química , Humanos , Cinética , Estructura Molecular , Monofenol Monooxigenasa/metabolismo , Relación Estructura-Actividad
15.
Bioorg Chem ; 79: 257-264, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29778797

RESUMEN

Beside other pharmaceutical benefits, flavonoids are known for their potent α-glucosidase inhibition. In the present study, we investigated α-glucosidase inhibitory effects of structurally related 11 flavonols, among which quercetin-3-O-(3″-O-galloyl)-ß-galactopyranoside (8) and quercetin 3-O-(6″-O-galloyl)-ß-glucopyranoside (9) showed significant inhibition compared to the positive control, acarbose, with IC50 values of 0.97 ±â€¯0.02 and 1.35 ±â€¯0.06 µM, respectively. It was found that while sugar substitution to C3-OH of C ring reduced the α-glucosidase inhibitory effect, galloyl substitution to these sugar units increased it. An enzyme kinetics analysis revealed that 7 was competitive, whereas 1, 2, 8, and 9 were uncompetitive inhibitors. In the light of these findings, we performed molecular docking studies to predict their inhibition mechanisms at atomic level.


Asunto(s)
Descubrimiento de Drogas , Flavonoles/farmacología , Inhibidores de Glicósido Hidrolasas/farmacología , Simulación del Acoplamiento Molecular , alfa-Glucosidasas/metabolismo , Relación Dosis-Respuesta a Droga , Flavonoles/síntesis química , Flavonoles/química , Inhibidores de Glicósido Hidrolasas/síntesis química , Inhibidores de Glicósido Hidrolasas/química , Humanos , Cinética , Estructura Molecular , Relación Estructura-Actividad
16.
Bioorg Chem ; 81: 545-552, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30245236

RESUMEN

Some Geranium species have been used to treat diabetes. To evaluate the scientific basis of this ethnopharmacological use, we aimed to isolate potent α-glucosidase inhibitory metabolites of Geranium asphodeloides Burm. through in vitro bioactivity-guided fractionation. All the tested extracts showed high α-glucosidase inhibitory effect compared to acarbose. Among the tested extracts, the ethyl acetate subextract showed the highest activity with an IC50 value of 0.85 ±â€¯0.01 µM. A hydrolysable tannin, 1,2,4-tri-O-galloyl-ß-d-glucopyranose (1), and five flavonoid glycosides, kaempferol-3-O-α-rhamnopyranoside (2), kaempferol-3-O-α-arabinofuranoside (3), quercetin-3-O-ß-glucopyranoside (4), quercetin-3-O-α-rhamnopyranoside (5), and quercetin-3-O-α-rhamnofuranoside (6), were isolated from the ethyl acetate subextract. Their structures were identified by 1D- and 2D-NMR experiments. 1 exhibited the highest α-glucosidase inhibitory effect, approximately 61 times more potent than positive control, acarbose, with an IC50 value of 0.95 ±â€¯0.07 µM. Also, 2 was more potent than acarbose. An enzyme kinetics analysis revealed that compounds 2, 3 and 4 were competitive, whereas 1 and 6 uncompetitive inhibitors. Molecular docking studies were performed to get insights into inhibition mechanisms of the isolated compounds in the light of the enzyme kinetic studies using various binding sites of the enzyme model.


Asunto(s)
Geranium/química , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Polifenoles/química , Polifenoles/farmacología , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimología , alfa-Glucosidasas/metabolismo , Simulación del Acoplamiento Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología
17.
Arch Pharm (Weinheim) ; 350(2)2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28032664

RESUMEN

New 3,5-disubstituted-2-pyrazoline derivatives (4-6), their boron-fluorine complexes (boron (3-(2'-aminophenyl),5-(2'-/3'-/4'-pyridyl)pyrazoline, BOAPPY) (7-9) and boron 1,2'-diazaflavone complex (BODAF) (11) were synthesized starting from azachalcones (1-3) to diazaflavone (10), respectively. Biological evaluation of compounds 4-9 and 11 showed remarkable antioxidant, antibacterial, and acetylcholinesterase and tyrosinase enzyme inhibition activities. All newly synthesized compounds 4-9 and 11 showed respectable antibacterial effect with minimum inhibitory concentrations in the range of 4.7-150 µg/mL.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Boro/química , Inhibidores de la Colinesterasa/farmacología , Flúor/química , Monofenol Monooxigenasa/antagonistas & inhibidores , Pirazoles/síntesis química , Pirazoles/farmacología , Antibacterianos/síntesis química , Antioxidantes/síntesis química , Inhibidores de la Colinesterasa/síntesis química , Relación Dosis-Respuesta a Droga , Depuradores de Radicales Libres/síntesis química , Depuradores de Radicales Libres/farmacología , Técnicas In Vitro , Pruebas de Sensibilidad Microbiana , Pirazoles/química , Relación Estructura-Actividad
18.
Arch Pharm (Weinheim) ; 349(11): 881-888, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27681014

RESUMEN

Novel 2-substitutedbenzyl-4(7)-phenyl-1H-benzo[d]imidazole compounds were synthesized and characterized. Although 2a and 2b were reported previously in the literature, 11 compounds were synthesized (nine of them were newly synthesized) and the tyrosinase inhibitory effects and antioxidant activities of these compounds were studied for the first time. All of the synthesized compounds displayed certain inhibitory effects on tyrosinase, with IC50 values ranging from 37.86 ± 0.24 to 75.81 ± 2.49 µM. Among the compounds, 2j exhibited similar tyrosinase inhibitory effect (IC50 = 37.86 ± 0.24 µM) to the positive control, kojic acid (IC50 = 21.93 ± 0.11 µM). Kinetic studies revealed it to act as non-competitive tyrosinase inhibitor with a Ki value of 50.2 µM. The antioxidant activities of the compounds were investigated by using in vitro antioxidant assays, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP). All of these results indicated that the compounds might have potential application as tyrosinase inhibitors.


Asunto(s)
Antioxidantes/síntesis química , Antioxidantes/farmacología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Imidazoles/síntesis química , Imidazoles/farmacología , Monofenol Monooxigenasa/antagonistas & inhibidores , Relación Dosis-Respuesta a Droga , Técnicas In Vitro , Pironas/farmacología , Relación Estructura-Actividad
19.
J Inorg Biochem ; 257: 112581, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38718499

RESUMEN

Type 2 diabetes (T2DM) is a progressive metabolic disease associated with high blood sugar levels that affects 537 million people worldwide. This study aim is to investigate the potential for use in the treatment of T2DM by examining the in vitro glucosidase inhibitory effects of novel synthesized metallophthalocyanines. For this reason, we have synthesized cobalt(II), copper(II) phthalocyanines (3PY-ON-CoQ, 3PY-ON-CuQ) that are both water-soluble and do not aggregate in water. These compounds were characterized by using various spectroscopic methods. The α-glucosidase inhibitory properties of 3PY-ON-CoQ and 3PY-ON-CuQ were carried out using the spectrophotometric method. Then, Lineweaver-Burk and Dixon plots were examined to determine the inhibitory type and constant (Ki). The IC50 values of 3PY-ON-CoQ and 3PY-ON-CuQ were 6.85 ± 1.25 µM and 55.09 ± 2.64 µM, respectively. Both compounds displayed mixed inhibitory effects on α-glucosidase according to Lineweaver-Burk plots. The Ki values of 3PY-ON-CoQ and 3PY-ON-CuQ were calculated as 6.30 ± 1.55 µM and 54.25 ± 1.20 µM, respectively. The results of this work may lead to the discovery of new compounds for the treatment of T2DM.


Asunto(s)
Cobalto , Cobre , Inhibidores de Glicósido Hidrolasas , Indoles , Isoindoles , alfa-Glucosidasas , Inhibidores de Glicósido Hidrolasas/química , Inhibidores de Glicósido Hidrolasas/farmacología , Inhibidores de Glicósido Hidrolasas/síntesis química , Cobre/química , Indoles/química , Indoles/farmacología , Isoindoles/química , Isoindoles/farmacología , alfa-Glucosidasas/metabolismo , Cobalto/química , Solubilidad , Agua/química , Complejos de Coordinación/química , Complejos de Coordinación/farmacología , Complejos de Coordinación/síntesis química
20.
Nat Prod Res ; : 1-8, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949574

RESUMEN

This study aimed to evaluate the potential of Hedera colchica as an alternative to Hedera helix species for the treatment of mild inflammatory conditions of the upper respiratory tract and chronic inflammatory bronchial diseases. The H. colchica extract with the highest saponin content (C3S; 468.19 ± 16.01 mg HE/g dry weight) and the extract with the highest total phenol content (C1F; 108.60 ± 5.61 mg GAE/g dry weight). Chemical analysis and standardisation of the extract with the highest selective COX-2 inhibitory effect was performed using the LC-MS/MS technique. It was determined that the substances found in the highest ratio in the C1F extract were quinic acid (45.909 µg/g extract) and hesperidin (37.077 µg/g extract). As a result, secondary metabolites, in addition to saponins, found in Hedera species may also contribute to the extract's effectiveness, more potent extracts can be obtained compared to the total extract-containing preparations available in the market.

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