Sickling-suppressive effects of chrysin may be associated with sequestration of deoxy-haemoglobin, 2,3-bisphosphoglycerate mutase, alteration of redox homeostasis and functional chemistry of sickle erythrocytes

Sickle cell disease (SCD) is a medical condition caused by mutation in a single nucleotide in the β-globin gene. It is a health problem for people in sub-Saharan Africa, the Middle East and India. Orthodox drugs developed so far for SCD focus largely on symptomatic respite of pain and crisis mitigation. We investigated the antisickling effects of chrysin via modulation of deoxy-haemoglobin, 2,3-bisphosphoglycerate mutase, redox homeostasis and alteration of functional chemistry in human sickle erythrocytes. In silico and in vitro methods were adopted for the studies. Chrysin was docked against deoxy-haemoglobin and 2,3-bisphosphoglycerate mutase, with binding energies (−24.064 and −18.171 kcal/mol) and inhibition constant ( K i) of 0.990 µM and 0.993 µM at their active sites through strong hydrophobic and hydrogen bond interactions. Sickling was induced with 2% metabisulphite at 3 h. Chrysin was able to prevent sickling maximally at 2.5 µg/mL and reversed the same at 12.5 µg/mL, by 66.5% and 69.6%, respectively. Treatment with chrysin significantly ( p < 0.05) re-established the integrity of erythrocytes membrane as evident from the observed percentage of haemolysis relative to induced erythrocytes. Chrysin also significantly ( p < 0.05) prevented and reversed lipid peroxidation. Similarly, glutathione and catalase levels were observed to significantly ( p < 0.05) increase with concomitant significant ( p < 0.05) decrease in superoxide dismutase activity relative to untreated. From Fourier-transform infrared results, treatment with chrysin was able to favourably alter the functional chemistry, judging from the shifts and functional groups observed. Sickling-suppressive effects of chrysin may therefore be associated with sequestration of deoxy-haemoglobin, 2,3-bisphosphoglycerate mutase, alteration of redox homeostasis and functional chemistry of sickle erythrocytes.

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Antisickling Effects of Quercetin may be Associated with Modulation of Deoxyhaemoglobin, 2, 3-bisphosphoglycerate mutase, Redox Homeostasis and Alteration of Functional Chemistry in Human Sickle Erythrocytes.

Annals of Science and Technology ◽

10.2478/ast-2019-0005 ◽

2019 ◽

Vol 4 (1) ◽

pp. 38-47 ◽

Cited By ~ 2

Author(s):

Aliyu Muhammad ◽

Aliyu Dahiru Waziri ◽

Gilead Ebiegberi Forcados ◽

Babangida Sanusi ◽

Hadiza Sani ◽

...

Keyword(s):

Sickle Cell Anaemia ◽

Redox Homeostasis ◽

In Vitro Models ◽

Binding Energies ◽

Hydrogen Bond Interactions ◽

Sickle Erythrocyte ◽

Sickle Erythrocytes ◽

Catalytic Sites ◽

Bisphosphoglycerate Mutase

AbstractIt is now glaring that sickle cell anaemia is still one of the highest leading inbred hemoglobinopathy amongst Africans. This study examined the antisickling effects of quercetin via modulation of deoxy-haemoglobin, redox homeostasis and alteration of functional chemistry in human sickle erythrocyte using in silico and in vitro models while espousing preventive and curative approaches. Quercetin was docked against deoxy-haemoglobin and 2, 3-bisphosphoglycerate mutase, with binding energies (−30.427 and −21.106 kcal/mol) and Ki of 0.988μM and 0.992μM at their catalytic sites via strong hydrophobic and hydrogen bond interactions. Induction of sickling was done using 2% metabisulphite at 3h. Treatment with quercetin prevented sickling outstandingly at 5.0μg/mL and reversed same at 7.5μg/mL, 83.6% and 75.9%, respectively. Quercetin also significantly (P<0.05) maintained the integrity of erythrocyte membrane apparently from the observed % haemolysis relative to untreated. Quercetin significantly (P<0.05) prevented and counteracted lipid peroxidation while stimulating GSH and CAT levels which were detected to considerably (P<0.05) increase with simultaneous significant (P<0.05) reduction in SOD level based on curative approach. Umpiring from our FTIR results, a favorable alteration in the part of functional chemistry in terms of shifts (bend and stretches) and functional groups were observed relative to the induced erythrocyte/untreated. Thus, antisickling effects of quercetin may be associated with modulation of deoxy-haemoglobin, redox homeostasis and alteration of functional chemistry in human sickle erythrocytes.

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Discovery of a dual inhibitor of NQO1 and GSTP1 for treating glioblastoma

Journal of Hematology & Oncology ◽

10.1186/s13045-020-00979-y ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Kecheng Lei ◽

Xiaoxia Gu ◽

Alvaro G. Alvarado ◽

Yuhong Du ◽

Shilin Luo ◽

...

Keyword(s):

Oxidative Stress ◽

Crystal Structures ◽

Active Sites ◽

Redox Homeostasis ◽

Growth Factor Receptor ◽

Quinone Oxidoreductase ◽

Cancer Proliferation ◽

Dual Inhibitor

Abstract Background Glioblastoma (GBM) is a universally lethal tumor with frequently overexpressed or mutated epidermal growth factor receptor (EGFR). NADPH quinone oxidoreductase 1 (NQO1) and glutathione-S-transferase Pi 1 (GSTP1) are commonly upregulated in GBM. NQO1 and GSTP1 decrease the formation of reactive oxygen species (ROS), which mediates the oxidative stress and promotes GBM cell proliferation. Methods High-throughput screen was used for agents selectively active against GBM cells with EGFRvIII mutations. Co-crystal structures were revealed molecular details of target recognition. Pharmacological and gene knockdown/overexpression approaches were used to investigate the oxidative stress in vitro and in vivo. Results We identified a small molecular inhibitor, “MNPC,” that binds to both NQO1 and GSTP1 with high affinity and selectivity. MNPC inhibits NQO1 and GSTP1 enzymes and induces apoptosis in GBM, specifically inhibiting the growth of cell lines and primary GBM bearing the EGFRvIII mutation. Co-crystal structures between MNPC and NQO1, and molecular docking of MNPC with GSTP1 reveal that it binds the active sites and acts as a potent dual inhibitor. Inactivation of both NQO1 and GSTP1 with siRNA or MNPC results in imbalanced redox homeostasis, leading to apoptosis and mitigated cancer proliferation in vitro and in vivo. Conclusions Thus, MNPC, a dual inhibitor for both NQO1 and GSTP1, provides a novel lead compound for treating GBM via the exploitation of specific vulnerabilities created by mutant EGFR.

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Phloroglucinol as a Potential Candidate against Trypanosoma congolense Infection: Insights from In Vivo, In Vitro, Molecular Docking and Molecular Dynamic Simulation Analyses

Molecules ◽

10.3390/molecules27020469 ◽

2022 ◽

Vol 27 (2) ◽

pp. 469

Author(s):

Nasirudeen Idowu Abdulrashid ◽

Suleiman Aminu ◽

Rahma Muhammad Adamu ◽

Nasir Tajuddeen ◽

Murtala Bindawa Isah ◽

...

Keyword(s):

Molecular Docking ◽

Docking Studies ◽

Binding Energies ◽

Sub Saharan Africa ◽

Dynamics Simulation ◽

Potential Candidate ◽

Inhibitory Effects ◽

Hydrogen Bond Interaction

Sub-Saharan Africa is profoundly challenged with African Animal Trypanosomiasis and the available trypanocides are faced with drawbacks, necessitating the search for novel agents. Herein, the chemotherapeutic potential of phloroglucinol on T. congolense infection and its inhibitory effects on the partially purified T. congolense sialidase and phospholipase A2 (PLA2) were investigated. Treatment with phloroglucinol for 14 days significantly (p < 0.05) suppressed T. congolense proliferation, increased animal survival and ameliorated anemia induced by the parasite. Using biochemical and histopathological analyses, phloroglucinol was found to prevent renal damages and splenomegaly, besides its protection against T. congolense-associated increase in free serum sialic acids in infected animals. Moreover, the compound inhibited bloodstream T. congolense sialidase via mixed inhibition pattern with inhibition binding constant (Ki) of 0.181 µM, but a very low uncompetitive inhibitory effects against PLA2 (Ki > 9000 µM) was recorded. Molecular docking studies revealed binding energies of −4.9 and −5.3 kcal/mol between phloroglucinol with modeled sialidase and PLA2 respectively, while a 50 ns molecular dynamics simulation using GROMACS revealed the sialidase-phloroglucinol complex to be more compact and stable with higher free binding energy (−67.84 ± 0.50 kJ/mol) than PLA2-phloroglucinol complex (−77.17 ± 0.52 kJ/mol), based on MM-PBSA analysis. The sialidase-phloroglucinol complex had a single hydrogen bond interaction with Ser453 while none was observed for the PLA2-phloroglucinol complex. In conclusion, phloroglucinol showed moderate trypanostatic activity with great potential in ameliorating some of the parasite-induced pathologies and its anti-anemic effects might be linked to inhibition of sialidase rather than PLA2.

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Structure-based analysis of a natural GOT1-inhibitor Aspulvinone H arrests pancreatic ductal adenocarcinoma cells growth

10.22541/au.161881470.02929068/v1 ◽

2021 ◽

Author(s):

Zhang Yonghui ◽

Shan Yan ◽

Wei Song ◽

Qianqian Xu ◽

Changxing Qi ◽

...

Keyword(s):

Pancreatic Ductal Adenocarcinoma ◽

Anticancer Agents ◽

Active Sites ◽

Redox Homeostasis ◽

Xenograft Model ◽

Glutamine Metabolism ◽

Ductal Adenocarcinoma ◽

Biological Study

Pancreatic ductal adenocarcinoma (PDAC) cells are Gln-metabolism dependence, which can preferentially utilize glutamic oxaloacetate transaminase 1 (GOT1) to maintain the redox homeostasis of cancer cells. Therefore, small molecule inhibitors targeting GOT1 can be used as a new strategy for developing cancer therapies. Here, we identified a cyclobutyrolactone lignan, Aspulvinone H (AH), showing significant GOT1 inhibitory activity in vitro. The complex crystal structure of GOT1-AH elucidated the molecular mechanism, which AH and the cofactor pyrido-aldehyde 5-phosphate (PLP) competitively bound to the active sites of GOT1. Structure-activity relationship (SAR) analysis exhibited that the π-π stacking and isopentenyl side chain of aspulvinone were related to the inhibition of GOT1 activity. Further biological study indicated that AH could suppress glutamine metabolism, which made PDAC cells sensitive to oxidative stress and inhibited cell proliferation. Besides, AH exhibited potent in vivo antitumor activity in the SW1990 cell-induced xenograft model. These findings suggest that AH could be considered as a promising lead molecule for the development of PDAC anticancer agents.

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Mechanochemical Synthesis, in vitro Evaluation and Molecular Docking Studies of 4-Amino-2-arylamino-5-(benzofuran-2-oyl)thiazoles as Antidiabetic Agents

Letters in Organic Chemistry ◽

10.2174/1570178615666180815124425 ◽

2019 ◽

Vol 16 (7) ◽

pp. 560-568

Author(s):

Vijayan R. Akhila ◽

Maheswari R. Priya ◽

Daisy R. Sherin ◽

Girija K. Krishnapriya ◽

Sreerekha V. Keerthi ◽

...

Keyword(s):

Molecular Docking ◽

Mechanochemical Synthesis ◽

Active Sites ◽

Docking Studies ◽

Binding Energies ◽

Antidiabetic Activity ◽

Antidiabetic Agents ◽

Molecular Docking Studies ◽

Ic50 Value

The synthesis of 4-amino-2-arylamino-5-(benzofuran-2-oyl)thiazoles 4a-h, as example of 2,4-diaminothiazole-benzofuran hybrids and an evaluation of their antidiabetic activity, by in vitro and computational methods, are reported. The synthesis of these diaminothiazoles was achieved mechano chemically by a rapid solvent-less method. Their antidiabetic activity was assessed by α-glucosidase and α-amylase inhibition assays. The, IC50 value for α-glucosidase inhibition by 4-amino-5- (benzofuran-2-oyl)-2-(4-methoxyphenylamino)thiazole (4d) was found to be 20.04 µM and the IC50 value for α-amylase inhibition, 195.03 µM, whereas the corresponding values for reference acarbose were 53.38 µM and 502.03 µM, respectively. Molecular docking studies at the active sites of α- glucosidase and α-amylase showed that among the diaminothiazoles 4a-h now studied, 4-amino-5- (benzofuran-2-oyl)-2-(4-methoxyphenylamino)thiazole (4d) has the highest D-scores of -8.63 and -8.08 for α-glucosidase and for α-amylase, with binding energies -47.76 and -19.73 kcal/mol, respectively.

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Potency of bisresorcinol from Heliciopsis terminalis on skin aging: in vitro bioactivities and molecular interactions

PeerJ ◽

10.7717/peerj.11618 ◽

2021 ◽

Vol 9 ◽

pp. e11618

Author(s):

Charinrat Saechan ◽

Uyen Hoang Nguyen ◽

Zhichao Wang ◽

Sachiko Sugimoto ◽

Yoshi Yamano ◽

...

Keyword(s):

Active Sites ◽

Ethanolic Extract ◽

Skin Aging ◽

Spectroscopic Technique ◽

Binding Energies ◽

Preparative Chromatography ◽

Hydroxyl Groups ◽

Cosmetic Products ◽

Hydrogen Binding

Background A bisresorcinol was isolated as the main constituent of Heliciopsis terminalis’s trunk (Proteaceae). Recently, resorcinol is applied as an active whitening agent in various cosmetic products. Because of the structural mimic to resorcinol, benefits of the bisresorcinol as an aging-enzyme antagonist were demonstrated in this study. Methods The bisresorcinol was purified from the crude ethanolic extract of H. terminalis’s trunk by solvent extraction and preparative chromatography, respectively. Inhibitory activity on collagenase, elastase, and tyrosinase of the compound was investigated by using a different spectroscopic technique. Molecular docking was carried out to predict possible interactions of the substance around the enzyme active sites. Results The IC50 values on collagenase of the bisresorcinol and caffeic acid were 156.7 ± 0.7 and 308.9 ± 1.6 µmole L−1, respectively. For elastase activity, the IC50 of 33.2 ± 0.5 and 34.3 ± 0.3 µmole L−1 was respectively determined for the bisresorcinol and ursolic acid. The bisresorcinol was inhibitory to tyrosinase by exhibiting the IC50 of 22.8 µmole L−1, and that of 78.4 µmole L−1 was present for β-arbutin. The bisresorcinol bound to collagenase, elastase, and tyrosinase with the respective binding energies of −5.89, −5.69, and −6.57 kcal mol−1. These binding energies were in the same ranges of tested inhibitors. The aromatic phenol groups in the structure were responsible for principle as well as supporting binding interactions with enzymes. Hydrogen binding due to hydroxyl groups and π-related attractive forces from an aromatic ring(s) provided binding versatility to bisresorcinol. Conclusion The bisresorcinol purified from H. terminalis might be useful for inclusion in cosmetic products as an aging-enzyme antagonist.

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On the Adsorption of Aspartate Derivatives to Calcite Surfaces in Aqueous Environment

10.26434/chemrxiv.11558430.v1 ◽

2020 ◽

Author(s):

Robert Stepic ◽

Lara Jurković ◽

Ksenia Klementyeva ◽

Marko Ukrainczyk ◽

Matija Gredičak ◽

...

Keyword(s):

Active Sites ◽

Realistic Model ◽

Binding Energies ◽

Inhibition Mechanism ◽

Aqueous Environment ◽

Binding Modes ◽

Carboxylate Groups ◽

Dissolved Ions ◽

Living Organisms ◽

Dynamics Simulations

In many living organisms, biomolecules interact favorably with various surfaces of calcium carbonate. In this work, we have considered the interactions of aspartate (Asp) derivatives, as models of complex biomolecules, with calcite. Using kinetic growth experiments, we have investigated the inhibition of calcite growth by Asp, Asp2 and Asp3.This entailed the determination of a step-pinning growth regime as well as the evaluation of the adsorption constants and binding free energies for the three species to calcite crystals. These latter values are compared to free energy profiles obtained from fully atomistic molecular dynamics simulations. When using a flat (104) calcite surface in the models, the measured trend of binding energies is poorly reproduced. However, a more realistic model comprised of a surface with an island containing edges and corners, yields binding energies that compare very well with experiments. Surprisingly, we find that most binding modes involve the positively charged, ammonium group. Moreover, while attachment of the negatively charged carboxylate groups is also frequently observed, it is always balanced by the aqueous solvation of an equal or greater number of carboxylates. These effects are observed on all calcite features including edges and corners, the latter being associated with dominant affinities to Asp derivatives. As these features are also precisely the active sites for crystal growth, the experimental and theoretical results point strongly to a growth inhibition mechanism whereby these sites become blocked, preventing further attachment of dissolved ions and halting further growth.

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Targeting PPARalpha in Alzheimer's Disease

Current Alzheimer Research ◽

10.2174/1567205014666170505094549 ◽

2018 ◽

Vol 15 (4) ◽

pp. 345-354 ◽

Cited By ~ 13

Author(s):

Barbara D'Orio ◽

Anna Fracassi ◽

Maria Paola Cerù ◽

Sandra Moreno

Keyword(s):

Oxidative Stress ◽

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Molecular Mechanisms ◽

Redox Homeostasis ◽

Antioxidant Response ◽

Peroxisome Proliferator ◽

Prevailing Paradigm

Background: The molecular mechanisms underlying Alzheimer's disease (AD) are yet to be fully elucidated. The so-called “amyloid cascade hypothesis” has long been the prevailing paradigm for causation of disease, and is today being revisited in relation to other pathogenic pathways, such as oxidative stress, neuroinflammation and energy dysmetabolism. The peroxisome proliferator-activated receptors (PPARs) are expressed in the central nervous system (CNS) and regulate many physiological processes, such as energy metabolism, neurotransmission, redox homeostasis, autophagy and cell cycle. Among the three isotypes (α, β/δ, γ), PPARγ role is the most extensively studied, while information on α and β/δ are still scanty. However, recent in vitro and in vivo evidence point to PPARα as a promising therapeutic target in AD. Conclusion: This review provides an update on this topic, focussing on the effects of natural or synthetic agonists in modulating pathogenetic mechanisms at AD onset and during its progression. Ligandactivated PPARα inihibits amyloidogenic pathway, Tau hyperphosphorylation and neuroinflammation. Concomitantly, the receptor elicits an enzymatic antioxidant response to oxidative stress, ameliorates glucose and lipid dysmetabolism, and stimulates autophagy.

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Polyamines and Related Nitrogen Compounds in the Chemotherapy of Neglected Diseases Caused by Kinetoplastids

Current Topics in Medicinal Chemistry ◽

10.2174/1568026618666180427151338 ◽

2018 ◽

Vol 18 (5) ◽

pp. 321-368 ◽

Cited By ~ 2

Author(s):

Juan A. Bisceglia ◽

Maria C. Mollo ◽

Nadia Gruber ◽

Liliana R. Orelli

Keyword(s):

Drug Targets ◽

Redox Homeostasis ◽

Cost Effective ◽

Structural Features ◽

Mammalian Host ◽

Neglected Diseases ◽

Nitrogen Compounds ◽

Chemical Structures

Neglected diseases due to the parasitic protozoa Leishmania and Trypanosoma (kinetoplastids) affect millions of people worldwide, and the lack of suitable treatments has promoted an ongoing drug discovery effort to identify novel nontoxic and cost-effective chemotherapies. Polyamines are ubiquitous small organic molecules that play key roles in kinetoplastid parasites metabolism, redox homeostasis and in the normal progression of cell cycles, which differ from those found in the mammalian host. These features make polyamines attractive in terms of antiparasitic drug development. The present work provides a comprehensive insight on the use of polyamine derivatives and related nitrogen compounds in the chemotherapy of kinetoplastid diseases. The amount of literature on this subject is considerable, and a classification considering drug targets and chemical structures were made. Polyamines, aminoalcohols and basic heterocycles designed to target the relevant parasitic enzyme trypanothione reductase are discussed in the first section, followed by compounds directed to less common targets, like parasite SOD and the aminopurine P2 transporter. Finally, the third section comprises nitrogen compounds structurally derived from antimalaric agents. References on the chemical synthesis of the selected compounds are reported together with their in vivo and/or in vitro IC50 values, and structureactivity relationships within each group are analyzed. Some favourable structural features were identified from the SAR analyses comprising protonable sites, hydrophobic groups and optimum distances between them. The importance of certain pharmacophoric groups or amino acid residues in the bioactivity of polyamine derived compounds is also discussed.

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1'-methylspiro[indoline-3,4'-piperidine] Derivatives: Design, Synthesis, Molecular Docking and Anti-tumor Activity Studies

Letters in Drug Design & Discovery ◽

10.2174/1570180817999201117150714 ◽

2020 ◽

Vol 17 ◽

Author(s):

Junjian Li ◽

Lianbao Ye ◽

Yuanyuan Wang ◽

Ying Liu ◽

Xiaobao Jin ◽

...

Keyword(s):

Molecular Docking ◽

Cell Lines ◽

Active Sites ◽

Biological Activities ◽

Significant Inhibition ◽

Alkaline Condition ◽

Discovery Studio ◽

Hela Cell Lines ◽

Antiproliferative Activities

Background: Spirocyclic indoline compounds widely exist in numerous natural products with good biological activities and some drug molecules in many aspects. In recent years, it has attracted extensive attention as potent anti-tumor agents in the fields of pharmacology and chemistry. Objective: In this study, we focused on designing and synthesizing a set of novel 1'-H-spiro[indole-3,4'-piperidine] derivatives, which were evaluated by preliminary bioactivity experiment in vitro and molecular docking. Method: The key intermediate 1'-methylspiro[indoline-3,4'-piperidine] (B4) reacted with benzenesulfonyl chloride with different substituents under alkaline condition to obtain its sulfonyl derivatives (B5-B10). We evaluated their antiproliferative activities against A549, BEL-7402 and HeLa cells by MTT assay. We performed the CDOCKER module in Discovery Studio 2.5.5 software for molecular modeling of compound B5, and investigated the binding of compound B5 with the target proteins from PDB database. Results: The results indicated that compounds B4-B10 exhibited good antiproliferative activities against the above three types of cells, in which compound B5 with chloride atom as electron-withdrawing substituent on a phenyl ring showed the highest potency against BEL-7402 cells (IC50=30.03±0.43 μg/mL). By binging of the prominent bioactive compound B5 to CDK, c-Met, EGFR protein crystals, The binding energy of B5 with these three types receptors are -44.3583 kcal/mol, - 38.3292 kcal/mol, -33.3653 kcal/mol respectively. Conclusion: Six 1'-methylspiro[indoline-3,4'-piperidine] derivatives were synthesized and evaluated against BEL-7402, A- 549, HeLa cell lines. Compound B5 showed significant inhibition on BEL-7402 cell lines. Molecular docking revealed that B5 showed good affinity by the good fitting between B5 and these three targets with amino acid residues in active sites which encourage us to conduct further evaluation such as the kinase experiment.

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