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1.
Bioinform Biol Insights ; 18: 11779322231223857, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38283284

RESUMO

The study investigated the antidiabetic potentials of the fruit extract of Parquetina nigrescens with the aim of justifying its folkloric antidiabetic usage in some part of Nigeria. Acute toxicity test of the plant extract was assessed using Lorke's method. Its antidiabetic activities were assayed in α-amylase, α-glucosidase, glucose, and streptozotocin-induced diabetic rats' models at various doses with acarbose and glibenclamide (5 mg/kg) as positive controls. Molecular docking studies were performed to identify the antidiabetic constituent of the extract and elucidate its possible mechanism of action. The estimated median lethal dose (LD50) of the extract was above 5000 mg/kg. In the α-amylase, α-glucosidase study, the extract elicited concentration-dependent activity similar to acarbose. In the glucose-induced hyperglycaemic model, 200 mg/kg of the extract was the most effective dose with comparable (P > .05) antihyperglycaemic activity to glibenclamide (5 mg kg) at 1 to 4 h. Also in the streptozotocin-induced diabetic rats model, 100 and 200 mg/kg of the extract gave comparable (P > 0.05) activity on days 4 to 14 that were significantly better than that of glibenclamide on days 4 to 7. The n-hexane and ethylacetate fractions of the extract, both at 200 mg/kg were the most active with comparable activity to glibenclamide at all time points. The molecular docking studies identified isorhoifolin as the best binder against alpha amylase with binding energy (-9.1 kcal/mol), alpha glucosidase (-9.4 kcal/mol), sodium-glucose cotransporter-2 (-9.5 kcal/mol), peroxisome proliferator activated receptor gamma (-10.3 kcal/mol), 11ß-Hydroxysteroid dehydrogenase (-10.8 kcal/mol), and dipeptidyl peptidase IV (-9.4 kcal/mol). The results of the antidiabetic study of P nigrescence fruit extract justified its usage in ethnomedicne in diabetes management.

2.
J Biomol Struct Dyn ; 42(5): 2570-2585, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37116195

RESUMO

Malaria is among the top-ranked parasitic diseases that pose a threat to the existence of the human race. This study evaluated the antimalarial effect of the rhizome of Zingiber officinale in infected mice, performed secondary metabolite profiling and detailed computational antimalarial evaluation through molecular docking, molecular dynamics (MD) simulation and density functional theory methods. The antimalarial potential of Z. officinale was performed using the in vivo chemosuppressive model; secondary metabolite profiling was carried out using liquid chromatography-mass spectrometry (LC-MS). Molecular docking was performed with Autodock Vina while the MD simulation was performed with Schrodinger desmond suite for 100 ns and DFT calculations with B3LYP (6-31G) basis set. The extract showed 64% parasitaemia suppression, with a dose-dependent increase in activity up to 200 mg/kg. The chemical profiling of the extract tentatively identified eight phytochemicals. The molecular docking studies with plasmepsin II and Plasmodium falciparum dihydrofolate reductase-thymidylate synthase (PfDHFR-TS) identified gingerenone A as the hit molecule, and MMGBSA values corroborate the binding energies obtained. The electronic parameters of gingerenone A revealed its significant antimalarial potential. The antimalarial activity elicited by the extract of Z. officinale and the bioactive chemical constituent supports its usage in ethnomedicine.Communicated by Ramaswamy H. Sarma.


Assuntos
Antimaláricos , Diarileptanoides , Antagonistas do Ácido Fólico , Zingiber officinale , Humanos , Animais , Camundongos , Antimaláricos/química , Simulação de Acoplamento Molecular , Espectrometria de Massa com Cromatografia Líquida , Cromatografia Líquida , Espectrometria de Massas em Tandem , Antagonistas do Ácido Fólico/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Plasmodium falciparum
3.
Bioinform Biol Insights ; 18: 11779322231223851, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38250561

RESUMO

Type 2 diabetes is a major health concern contributing to most of diabetic cases worldwide. Mangiferin and its congeners are known for their diverse pharmacological properties. This study sought to investigate the inhibitory property of naturally occurring mangiferin congeners on sodium-glucose co-transporter 2 protein (SGLT-2) using comprehensive computational methods. The naturally occurring mangiferin congeners were subjected to molecular docking, molecular dynamics (MDs) simulation (100 ns), molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) binding free energy, density functional theory calculations (B3LYP 6-31G basis set), and ADMET approaches to identify potential SGLT-2 inhibitor. The molecular docking studies revealed neomangiferin (-9.0 kcal/mol) as the hit molecule compared with dapagliflozin (-8.3 kcal/mol). Root-mean-square deviation (RMSD) and root-mean-square fluctuation (RMSF) plots from the MD simulations established that neomangiferin stabilizes SGLT-2 better than the dapagliflozin, a standard drug. The MM-PBSA binding free energy calculations showed that neomangiferin (-26.05 kcal/mol) elicited better binding affinity than dapagliflozin (-17.42 kcal/mol). The electronic studies showed that neomangiferin (3.48 eV) elicited high electrophilicity index compared with mangiferin (3.31 eV) and dapagliflozin (2.11 eV). Also, the ADMET properties showed that the hit molecule is safe when administered to diabetic subjects. The current in silico studies suggest that neomangiferin could emerge as a promising lead molecule as a SGLT-2 inhibitor.

4.
J Biomol Struct Dyn ; 41(20): 10957-10968, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36940367

RESUMO

Alzheimer's disease is among the major health challenges that currently attract the attention of health care givers and drug discovery and development experts worldwide. This study investigated the acetylcholinesterase inhibitory activity of sappanin-type homisoflavonoids isolated from the inter-bulb surface of Scilla nervosa. Molecular docking, molecular dynamics simulation, ADMET and in vitro studies were performed to identify the hit molecules, understand their binding mode and interaction, druggability and establish their inhibitory potentials against acetylcholinesterase enzyme. The hit compounds 5, 2, 1 and 4 were identified as the hit molecules through the molecular docking. The molecular dynamics simulation and MM-PBSA analysis showed the hit homoisoflavonoids established stability and good binding affinity against the acetylcholinesterase enzyme. Also, 5 elicited the best inhibitory activity followed by 2, 1 and 4 in the in vitro experiment. Furthermore, the selected homoisoflavonoids exhibit interesting drug likeness and pharmacokinetic properties as drug candidate. The results suggest further investigations towards the development of the phytochemicals as possible acetylcholinesterase inhibitors.Communicated by Ramaswamy H. Sarma.


Assuntos
Acetilcolinesterase , Scilla , Humanos , Acetilcolinesterase/química , Simulação de Acoplamento Molecular , Scilla/metabolismo , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/química , Simulação de Dinâmica Molecular
5.
Bioinform Biol Insights ; 17: 11779322231154966, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36860650

RESUMO

Malaria is a deadly disease that continues to pose a threat to children and maternal well-being. This study was designed to identify the chemical constituents in the ethanolic fruit extract of Azadirachta indica, elucidate the pharmacological potentials of identified phytochemicals through the density functional theory method and carry out the antimalarial activity of extract using chemosuppression and curative models. The liquid chromatography-mass spectrometry (LC-MS) analysis of the ethanolic extract was carried out, followed by the density functional theory studies of the identified phytochemicals using B3LYP and 6-31G (d, p) basis set. The antimalarial assays were performed using the chemosuppression (4 days) and curative models. The LC-MS fingerprint of the extract led to the identification of desacetylnimbinolide, nimbidiol, O-methylazadironolide, nimbidic acid, and desfurano-6α-hydroxyazadiradione. Also, the frontier molecular orbital properties, molecular electrostatic potential, and dipole moment studies revealed the identified phytochemicals as possible antimalarial agents. The ethanolic extract of A indica fruit gave 83% suppression at 800 mg/kg, while 84% parasitaemia clearance was obtained in the curative study. The study provided information about the phytochemicals and background pharmacological evidences of the antimalarial ethnomedicinal claim of A indica fruit. Thus, isolation and structure elucidation of the identified phytochemicals from the active ethanolic extract and extensive antimalarial studies towards the discovery of new therapeutic agents is recommended for further studies.

6.
J Biomol Struct Dyn ; : 1-16, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37968884

RESUMO

Plamepsin II has been identified as a therapeutic target in the Plasmodium falciparum's life cycle and may lead to a drastic reduction in deaths caused by malaria worldwide. Africa flora is rich in medicinal qualities and possesses both simple and complex bioactive phytochemicals. This study utilized computational approaches like molecular docking, molecular dynamics simulation, quantum chemical calculations and ADMET to evaluate the plasmepsin II inhibitory properties of phytochemicals isolated from African antimalarial plants. Molecular docking was carried out to estimate the binding affinity of 229 phytochemicals whereby ekeberin A, dichamanetin, 10-hydroxyusambaresine, chamuvaritin and diuvaretin were selected. Further, RMSD and RMSF plots from the 100 ns simulation results showed that the screened phytochemicals were stable in the enzyme's binding pocket. The quantum chemical calculation revealed that all the phytochemicals are strong electrophiles, while ekeberin A was identified as the most stable and dichamanetin as the most reactive. Also, ADMET studies established the drug candidacy of the phytochemicals. Thus, these phytochemicals could act as good antimalarial agents after extensive in vitro and in vivo studies.Communicated by Ramaswamy H. Sarma.

7.
J Biomol Struct Dyn ; : 1-12, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38069604

RESUMO

Type 2 diabetes accounts for the largest percentage of all diabetic cases worldwide. Cucurbitane-type triterpenes are mainly found in Momordica charantia and possess excellent pharmacological activities. This study was designed to identify cucurbitane-type triterpene from Momordica charantia using Liquid Chromatography-Mass Spectrometry (LC-MS) analysis, examine its anti-diabetic property with molecular docking against diabetes enzymes (alpha-amylase, alpha-glucosidase, dipeptidyl dipeptidase IV and peroxisome proliferator-activated receptor gamma). The stability and interactions of the docked complexes were investigated using molecular dynamics simulation, while the pharmacokinetic and toxicity profile of the ligand was examined using an ADMET server. (23E)-Cucurbita-5,23,25-triene-3,7-dione (CUB) was identified from the LC-MS profiling of the methanolic extract of M. charantia. The molecular docking studies showed that the identified phytochemical elicited good binding energy against all the target receptors. The RMSD and RMSF plots obtained from the 100 ns molecular dynamics simulation showed that the ligand was stable and established substantial interactions with the amino acid residues of the diabetes enzymes which were confirmed by the MM\GBSA computations. The pharmacokinetic and toxicity properties of the ligand showed it was safer as an anti-diabetic drug candidate. Extensive isolation, in vitro and in vivo studies of the ligand against the diabetic enzymes is recommended.Communicated by Ramaswamy H. Sarma.

8.
Int J Obes (Lond) ; 36(1): 93-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21487397

RESUMO

BACKGROUND: Body size is associated with increased brachial systolic blood pressure (SBP) and aortic stiffness. The aims of this study were to determine the relationships between central SBP and body size (determined by body mass index (BMI), waist circumference and waist/hip ratio) in health and disease. We also sought to determine if aortic stiffness was correlated with body size, independent of BP. METHODS: BMI, brachial BP and estimated central SBP (by SphygmoCor and radial P2) were recorded in controls (n=228), patients with diabetes (n=211), coronary artery disease (n=184) and end-stage kidney disease (n=68). Additional measures of waist circumference and arterial stiffness (aortic and brachial pulse wave velocity (PWV)) were recorded in a subgroup of 75 controls (aged 51 ± 12 years) who were carefully screened for factors affecting vascular function. RESULTS: BMI was associated with brachial (r=0.30; P<0.001) and central SBP (r=0.29; P<0.001) in the 228 controls, but not the patient populations (r<0.13; P>0.15 for all comparisons). In the control subgroup, waist circumference was also significantly correlated with brachial SBP (r=0.29; P=0.01), but not central SBP (r=0.22; P=0.07). Independent predictors of aortic PWV in the control subgroup were brachial SBP (ß=0.43; P<0.001), age (ß=0.37; P<0.001), waist circumference (ß=0.39; P=0.02) and female sex (ß=-0.24; P=0.03), but not BMI. CONCLUSION: In health, there are parallel increases in central and brachial SBP as BMI increases, but these relationships are not observed in the presence of chronic disease. Moreover, BP is a stronger correlate of arterial stiffness than body size.


Assuntos
Pressão Sanguínea , Índice de Massa Corporal , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Falência Renal Crônica/fisiopatologia , Rigidez Vascular , Velocidade do Fluxo Sanguíneo , Artéria Braquial/fisiopatologia , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/epidemiologia , Doença Crônica , Estudos Transversais , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Ecocardiografia , Feminino , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/epidemiologia , Masculino , Manometria , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Fluxo Pulsátil , Fatores de Risco , Esfigmomanômetros , Circunferência da Cintura , Relação Cintura-Quadril
9.
J Biomol Struct Dyn ; 40(14): 6340-6349, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-33583331

RESUMO

This study aimed to identify novel α-amylase and α-glucosidase inhibitors from Nigerian antidiabetic plants through in silico approach. Virtual screening of the 93 phytoconstituents was performed, and their inhibitory potentials were ranked based on their docking scores. Five hit molecules were selected for each enzyme target with their hydrogen bonding, hydrophobic, electrostatic, and pi interactions analyzed with discovery studio visualizer. The drug-likeness and ADMET studies of the hit molecules were performed to ascertain their druggability properties. Further, three top-ranked hit molecules were subjected to molecular dynamics simulations. The virtual screening, drug-likeness property, and ADMET studies, and molecular dynamics simulations carried out reveal Newbouldiaquinone A, Foetidin, Chamuvaritin, Cajaflavanone, and Azadirolic acid as potential inhibitors of α-amylase while Chamuvaritin, Newbouldiaquinone A, Flowerone, Scoparic acid A and Nimonol were potential inhibitors of α-glucosidase enzyme.Communicated by Ramaswamy H. Sarma.


Assuntos
Inibidores de Glicosídeo Hidrolases , alfa-Amilases , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , Nigéria , Plantas , alfa-Amilases/química
10.
Bioinform Biol Insights ; 16: 11779322221118330, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046175

RESUMO

The inhibition of acetylcholinesterase plays a vital role in the treatment of Alzheimer disease. This study aimed to explore the acetylcholinesterase inhibition potential of Phyllanthus amarus and its phytoconstituents through an in vitro and in silico approach. The in vitro acetylcholinesterase inhibitory activity of P amarus was carried out, followed by the molecular docking studies of its phytoconstituents. The top-ranked molecules identified through molecular docking were subjected to molecular dynamics simulation (MDS) and density functional theory (DFT) studies. The results obtained revealed the methanolic extract of P amarus as a potent acetylcholinesterase inhibitor, while amarosterol A, hinokinin, ß-sitosterol, stigmasterol and ellagic acid were identified as potential acetylcholinesterase inhibitors. The MDS and DFT results are in agreement with those obtained from the docking studies. Our findings suggest further studies on the hit molecules.

12.
J Biomed Mater Res B Appl Biomater ; 106(5): 1987-1997, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28990317

RESUMO

Absorbable implants made of magnesium alloys may revolutionize surgical intervention, and fine magnesium wire will be critical to many applications. Functionally, the wires must have sufficient mechanical properties to withstand implantation and in-service loading, have excellent tissue tolerance, and exhibit an appropriate degradation rate for the application. Alloy chemistry and thermomechanical processing conditions will significantly impact the material's functional performance, but the exact translation of these parameters to implant performance is unclear. With this in mind, fine (127 µm) WE43B magnesium alloy wires in five thermomechanical process (TMP) conditions (90% cold work [CW], and 250, 375, 400, and 450°C heat treatments) were investigated for their effect on mechanical and corrosion behavior. The TMP conditions gave clear metallurgical differences: transverse grain dimensions ranged from 200 nm (CW) to 3 µm (450°C), UTS varied from 324 MPa (450°C) to 608 MPa (250°C), and surgical knotting showed some were suitable (CW, 400°C, 450°C) while others were not (250°C, 350°C). In vitro and in vivo corrosion testing yielded interesting and in some cases conflicting results. After 1 month immersion in cell culture medium, wire corrosion was extensive, and TMP conditions altered the macrocorrosion morphology but not the rate or total release of magnesium ions. After 1 month subdermal implantation in mice, all wires were well tolerated and showed very little corrosion (per µCT and histology), but differences in localized corrosion were detected between conditions. This study indicates that WE43B wires treated at 450°C may be most suitable for surgical knotting procedures. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1987-1997, 2018.


Assuntos
Implantes Absorvíveis , Ligas/química , Materiais Biocompatíveis/química , Fios Ortopédicos , Magnésio/química , Teste de Materiais , Animais , Corrosão , Feminino , Camundongos
13.
J Clin Endocrinol Metab ; 95(9): 4455-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20610595

RESUMO

CONTEXT: Postprandial dysmetabolism is emerging as an important cardiovascular risk factor. Augmentation index (AIx) is a measure of systemic arterial stiffness and independently predicts cardiovascular outcome. OBJECTIVE: The objective of this study was to assess the effect of a standardized high-fat meal on metabolic parameters and AIx in 1) lean, 2) obese nondiabetic, and 3) subjects with type 2 diabetes mellitus (T2DM). DESIGN AND SETTING: Male subjects (lean, n = 8; obese, n = 10; and T2DM, n = 10) were studied for 6 h after a high-fat meal and water control. Glucose, insulin, triglycerides, and AIx (radial applanation tonometry) were measured serially to determine the incremental area under the curve (iAUC). RESULTS: AIx decreased in all three groups after a high-fat meal. A greater overall postprandial reduction in AIx was seen in lean and T2DM compared with obese subjects (iAUC, 2251 +/- 1204, 2764 +/- 1102, and 1187 +/- 429% . min, respectively; P < 0.05). The time to return to baseline AIx was significantly delayed in subjects with T2DM (297 +/- 68 min) compared with lean subjects (161 +/- 88 min; P < 0.05). There was a significant correlation between iAUC AIx and iAUC triglycerides (r = 0.50; P < 0.05). CONCLUSIONS: Obesity is associated with an attenuated overall postprandial decrease in AIx. Subjects with T2DM have a preserved, but significantly prolonged, reduction in AIx after a high-fat meal. The correlation between AIx and triglycerides suggests that postprandial dysmetabolism may impact on vascular dynamics. The markedly different response observed in the obese subjects compared with those with T2DM was unexpected and warrants additional evaluation.


Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Dieta Aterogênica , Gorduras na Dieta/farmacologia , Obesidade/fisiopatologia , Resistência Vascular/efeitos dos fármacos , Adulto , Idoso , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Diabetes Mellitus Tipo 2/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Período Pós-Prandial/efeitos dos fármacos , Risco
14.
Microbiology (Reading) ; 149(Pt 5): 1357-1365, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12724397

RESUMO

Rhizobium leguminosarum fur mutants were unaffected in Fe-dependent regulation of several operons that specify different Fe uptake systems, yet cloned R. leguminosarum fur partially corrected an Escherichia coli fur mutant and R. leguminosarum Fur protein bound to canonical fur boxes. The lack of a phenotype in fur mutants is not due to functional redundancy with Irr, another member of the Fur superfamily found in the rhizobia, since irr fur double mutants are also unaffected in Fe-responsive regulation of several operons involved in Fe uptake. Neither Irr nor Fur is needed for symbiotic N(2) fixation on peas. As in Bradyrhizobium japonicum, irr mutants accumulated protoporphyrin IX. R. leguminosarum irr is not regulated by Fur and its Irr protein lacks the motif needed for haem-dependent post-translational modification that occurs in B. japonicum Irr. The similarities and differences in the Fur superfamily in the rhizobia and other Gram-negative bacteria are discussed.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Ferro/metabolismo , Mutação , Proteínas Repressoras/metabolismo , Rhizobium leguminosarum/metabolismo , Aldeído Oxirredutases/genética , Aldeído Oxirredutases/metabolismo , Proteínas de Bactérias/genética , Fixação de Nitrogênio , Pisum sativum/microbiologia , Rhizobium leguminosarum/genética , Rhizobium leguminosarum/crescimento & desenvolvimento , Simbiose , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica
15.
Biochem Soc Trans ; 30(4): 771-4, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12196192

RESUMO

The X-ray crystal structure of the apo-form of the Fur protein from Rhizobium leguminosarum has been solved at 2.7 A resolution. Small-angle X-ray scattering was used to give information on the solution conformation of the protein. The Fur homodimer folds into two domains. The N-terminal domain is formed from the packing of two helix-turn-helix motifs while the C-terminal domain appears primarily to stabilize the dimeric state of the protein.


Assuntos
Proteínas de Bactérias/química , Ferro/metabolismo , Proteínas Repressoras/química , Rhizobium leguminosarum/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , Metaloproteínas/química , Modelos Moleculares , Conformação Proteica
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