201
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In vitro and in silico evaluation of Centaurea saligna (K.Koch) Wagenitz—An endemic folk medicinal plant. Comput Biol Chem 2018; 73:120-126. [DOI: 10.1016/j.compbiolchem.2018.02.010] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2017] [Revised: 02/05/2018] [Accepted: 02/11/2018] [Indexed: 01/19/2023]
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202
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Wen H, Tang B, Stewart AJ, Tao Y, Shao Y, Cui Y, Yue H, Pei J, Liu Z, Mei L, Yu R, Jiang L. Erythritol Attenuates Postprandial Blood Glucose by Inhibiting α-Glucosidase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:1401-1407. [PMID: 29361825 DOI: 10.1021/acs.jafc.7b05033] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Diabetes mellitus (DM) is a serious metabolic disorder, where impaired postprandial blood glucose regulation often leads to severe health complications. The natural chemical erythritol is a C4 polyol approved by the U.S. Food and Drug Administration for use as a sweetener. Here, we examined a potential role for erythritol in the control of postprandial blood glucose levels in DM. An anti-postprandial hyperglycemia effect upon erythritol administration (500 mg kg-1) was demonstrated in alloxan-induced DM model mice by monitoring changes in blood glucose after intragastric administration of drugs and starch. We also found that erythritol most likely exerts its anti-postprandial hyperglycemic activities by inhibiting α-glucosidase in a competitive manner. This was supported by enzyme activity assays and molecular modeling experiments. In the latter experiments, it was possible to successfully dock erythritol into the catalytic pocket of α-glucosidase, with the resultant interaction likely driven by electrostatic interactions involving Asp215, Asp69, and Arg446 residues. This study suggests that erythritol may not only serve as a glucose substitute but also be a useful agent in the treatment of DM to help manage postprandial blood glucose levels.
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Affiliation(s)
- Huaixiu Wen
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
| | - Bowen Tang
- School of Pharmaceutical Sciences, Xiamen University , Xiamen, Fujian 361005, People's Republic of China
| | - Alan J Stewart
- School of Medicine, University of St Andrews , St Andrews KY16 9TF, United Kingdom
| | - Yanduo Tao
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
| | - Yun Shao
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
| | - Yulei Cui
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
| | - Huilan Yue
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
| | - Jinjin Pei
- Shaanxi Key Laboratory of Bioresources and Biology, Shaanxi University of Technology , Hanzhong, Shaanxi 723001, People's Republic of China
| | - Zenggen Liu
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
| | - Lijuan Mei
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
| | - Ruitao Yu
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
| | - Lei Jiang
- Key Laboratory of Tibetan Medicine Research, Northwest Plateau Institute of Biology, Chinese Academy of Sciences , 23 Xinning Road, Xining, Qinghai 810001, People's Republic of China
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203
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Ding H, Hu X, Xu X, Zhang G, Gong D. Inhibitory mechanism of two allosteric inhibitors, oleanolic acid and ursolic acid on α-glucosidase. Int J Biol Macromol 2018; 107:1844-1855. [PMID: 29030193 DOI: 10.1016/j.ijbiomac.2017.10.040] [Citation(s) in RCA: 94] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 09/19/2017] [Accepted: 10/09/2017] [Indexed: 11/28/2022]
Abstract
Glycemic control which can be efficaciously regulated by inhibiting α-glucosidase activity is an effective therapy for diabetes mellitus. This work is to investigate the kinetics and inhibition mechanism of oleanolic acid and ursolic acid on α-glucosidase. Oleanolic acid and ursolic acid exhibited potent inhibitory activities with IC50 values of (6.35±0.02)×10-6 and (1.69±0.03)×10-5molL-1 respectively in a reversible and non-competitive manner. Both of them binding to α-glucosidase induced the conformational change and intrinsic fluorescence quenching of α-glucosidase. The binding constants of oleanolic acid and ursolic acid with α-glucosidase at 298K were (2.04±0.02)×103 and (1.87±0.02)×103Lmol-1, respectively. Docking results showed that oleanolic acid and ursolic acid bound in different allosteric sites of cavity 2 and cavity 4 on α-glucosidase, respectively, which triggered allosteric regulation to perturb conformational dynamics of α-glucosidase, eventually leading to a decrease of catalytic activity of the enzyme. The substrate was not catalyzed by α-glucosidase to generate further products due to formation of a nonreactive ternary complex of oleanolic acid- or ursolic acid-α-glucosidase-substrate. The combination of oleanolic acid and ursolic acid displayed a significant synergistic inhibition on α-glucosidase.
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Affiliation(s)
- Huafang Ding
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China
| | - Xing Hu
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China
| | - Ximing Xu
- Institute of Bioinformatics and Medical Engineering, School of Electrical and Info- rmation Engineering, Jiangsu University of Technology, Changzhou 213001, China
| | - Guowen Zhang
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China.
| | - Deming Gong
- State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047, China; New Zealand Institute of Natural Medicine Research, 8 Ha Crescent, Auckland 2104, New Zealand
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204
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Han L, Zhang L, Ma W, Li D, Shi R, Wang M. Proanthocyanidin B2 attenuates postprandial blood glucose and its inhibitory effect on alpha-glucosidase: analysis by kinetics, fluorescence spectroscopy, atomic force microscopy and molecular docking. Food Funct 2018; 9:4673-4682. [DOI: 10.1039/c8fo00993g] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
As a dimer of proanthocyanidin, proanthocyanidin B2 (PB2) was found to effectively attenuate postprandial blood glucose in mice after sucrose loading.
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Affiliation(s)
- Lin Han
- College of Food Science and Engineering
- Northwest A&F University
- Yangling 712100
- P. R. China
- College of Biology and Food Engineering
| | - Lingling Zhang
- College of Food Science and Engineering
- Northwest A&F University
- Yangling 712100
- P. R. China
| | - Wenfang Ma
- College of Food Science and Engineering
- Northwest A&F University
- Yangling 712100
- P. R. China
| | - Ding Li
- College of Chemistry & Pharmacy
- Northwest A&F University
- Yangling 712100
- P. R. China
| | - Rujie Shi
- College of Biology and Food Engineering
- Chongqing Three Gorges University
- Chongqing 404100
- P. R. China
| | - Min Wang
- College of Food Science and Engineering
- Northwest A&F University
- Yangling 712100
- P. R. China
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205
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Wang L, Chen C, Zhang B, Huang Q, Fu X, Li C. Structural characterization of a novel acidic polysaccharide from Rosa roxburghii Tratt fruit and its α-glucosidase inhibitory activity. Food Funct 2018; 9:3974-3985. [DOI: 10.1039/c8fo00561c] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
An acidic polysaccharide (RTFP-3) extracted from Rosa roxburghii Tratt fruit can inhibit the activity of α-glucosidase.
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Affiliation(s)
- Lei Wang
- School of Food Science and Engineering
- Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety
- South China University of Technology
- Guangzhou 510640
- China
| | - Chun Chen
- School of Food Science and Engineering
- Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety
- South China University of Technology
- Guangzhou 510640
- China
| | - Bin Zhang
- School of Food Science and Engineering
- Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety
- South China University of Technology
- Guangzhou 510640
- China
| | - Qiang Huang
- School of Food Science and Engineering
- Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety
- South China University of Technology
- Guangzhou 510640
- China
| | - Xiong Fu
- School of Food Science and Engineering
- Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety
- South China University of Technology
- Guangzhou 510640
- China
| | - Chao Li
- School of Food Science and Engineering
- Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety
- South China University of Technology
- Guangzhou 510640
- China
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206
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A strategy for screening of α-glucosidase inhibitors from Morus alba root bark based on the ligand fishing combined with high-performance liquid chromatography mass spectrometer and molecular docking. Talanta 2017; 180:337-345. [PMID: 29332820 DOI: 10.1016/j.talanta.2017.12.065] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2017] [Revised: 12/14/2017] [Accepted: 12/21/2017] [Indexed: 11/23/2022]
Abstract
A new method based on ligand fishing combined with high-performance liquid chromatography quadrupole-time-of-flight mass spectrometer and molecular docking was established to screen α-glucosidase inhibitors from a traditional Chinese medicine Morus alba root bark. α-Glucosidase was immobilized on magnetic nanoparticles, used as a solid support to incubate with crude extract. After ligand fishing, the eluates were analyzed by high-performance liquid chromatography quadrupole-time-of-flight mass spectrometer, obtaining eleven ligands (1-4, 6-12) eventually. In order to discriminate the non-specific binders and discover powerful enzyme inhibitors, molecular docking was further performed and three of the eleven ligands were optimized to be excellent α-glucosidase inhibitors by the confirmation of isolation and bioassay of individual compounds. These three ligands, sanggenons G (6), O (7) and sanggenol G (12) exhibited striking inhibitory activities with extremely low IC50 values. The results suggest that established method will be applied to a wide range of target protein to screen potential bioactive constituents from herbal medicines.
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207
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Dai T, Yan X, Li Q, Li T, Liu C, McClements DJ, Chen J. Characterization of binding interaction between rice glutelin and gallic acid: Multi-spectroscopic analyses and computational docking simulation. Food Res Int 2017; 102:274-281. [DOI: 10.1016/j.foodres.2017.09.020] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 09/02/2017] [Accepted: 09/08/2017] [Indexed: 10/18/2022]
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208
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Proença C, Freitas M, Ribeiro D, Oliveira EFT, Sousa JLC, Tomé SM, Ramos MJ, Silva AMS, Fernandes PA, Fernandes E. α-Glucosidase inhibition by flavonoids: an in vitro and in silico structure-activity relationship study. J Enzyme Inhib Med Chem 2017; 32:1216-1228. [PMID: 28933564 PMCID: PMC6009965 DOI: 10.1080/14756366.2017.1368503] [Citation(s) in RCA: 222] [Impact Index Per Article: 31.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
α-Glucosidase inhibitors are described as the most effective in reducing post-prandial hyperglycaemia (PPHG) from all available anti-diabetic drugs used in the management of type 2 diabetes mellitus. As flavonoids are promising modulators of this enzyme’s activity, a panel of 44 flavonoids, organised in five groups, was screened for their inhibitory activity of α-glucosidase, based on in vitro structure–activity relationship studies. Inhibitory kinetic analysis and molecular docking calculations were also applied for selected compounds. A flavonoid with two catechol groups in A- and B-rings, together with a 3-OH group at C-ring, was the most active, presenting an IC50 much lower than the one found for the most widely prescribed α-glucosidase inhibitor, acarbose. The present work suggests that several of the studied flavonoids have the potential to be used as alternatives for the regulation of PPHG.
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Affiliation(s)
- Carina Proença
- a UCIBIO, REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy , University of Porto , Porto , Portugal
| | - Marisa Freitas
- a UCIBIO, REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy , University of Porto , Porto , Portugal
| | - Daniela Ribeiro
- a UCIBIO, REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy , University of Porto , Porto , Portugal
| | - Eduardo F T Oliveira
- b UCIBIO, REQUIMTE, Faculty of Sciences, Department of Chemistry and Biochemistry , University of Porto , Porto , Portugal
| | - Joana L C Sousa
- c Department of Chemistry & QOPNA , University of Aveiro , Aveiro , Portugal
| | - Sara M Tomé
- c Department of Chemistry & QOPNA , University of Aveiro , Aveiro , Portugal
| | - Maria J Ramos
- b UCIBIO, REQUIMTE, Faculty of Sciences, Department of Chemistry and Biochemistry , University of Porto , Porto , Portugal
| | - Artur M S Silva
- c Department of Chemistry & QOPNA , University of Aveiro , Aveiro , Portugal
| | - Pedro A Fernandes
- b UCIBIO, REQUIMTE, Faculty of Sciences, Department of Chemistry and Biochemistry , University of Porto , Porto , Portugal
| | - Eduarda Fernandes
- a UCIBIO, REQUIMTE, Laboratory of Applied Chemistry, Department of Chemical Sciences, Faculty of Pharmacy , University of Porto , Porto , Portugal
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209
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Zhang BW, Li X, Sun WL, Xing Y, Xiu ZL, Zhuang CL, Dong YS. Dietary Flavonoids and Acarbose Synergistically Inhibit α-Glucosidase and Lower Postprandial Blood Glucose. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:8319-8330. [PMID: 28875706 DOI: 10.1021/acs.jafc.7b02531] [Citation(s) in RCA: 118] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
The inhibition of porcine pancreatic α-amylase and mammalian α-glucosidase by 16 individual flavonoids was determined. The IC50 values for baicalein, (+)-catechin, quercetin, and luteolin were 74.1 ± 5.6, 175.1 ± 9.1, 281.2 ± 19.2, and 339.4 ± 16.3 μM, respectively, against α-glucosidase. The IC50 values for apigenin and baicalein were 146.8 ± 7.1 and 446.4 ± 23.9 μM, respectively, against α-amylase. The combination of baicalein, quercetin, or luteolin with acarbose showed synergistic inhibition, and the combination of (+)-catechin with acarbose showed antagonistic inhibition of α-glucosidase. The combination of baicalein or apigenin with acarbose showed additive inhibition of α-amylase at lower concentrations and antagonistic inhibition at a higher concentration. Kinetic studies of α-glucosidase activity revealed that baicalein alone, acarbose alone, and the combination showed noncompetitive, competitive, and mixed-type inhibition, respectively. Molecular modeling revealed that baicalein had higher affinity to the noncompetitive binding site of maltase, glucoamylase, and isomaltase subunits of α-glucosidase, with glide scores of -7.64, -6.98, and -6.88, respectively. (+)-Catechin had higher affinity to the active sites of maltase and glucoamylase and to the noncompetitive site of isomaltase. After sucrose loading, baicalein dose-dependently reduced the postprandial blood glucose (PBG) level in mice. The combination of 80 mg/kg baicalein and 1 mg/kg acarbose synergistically lowered the level of PBG, and the hypoglycemic effect was comparable to 8 mg/kg acarbose. The results indicated that baicalein could be used as a supplemental drug or dietary supplement in dietary therapy for diabetes mellitus.
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Affiliation(s)
- Bo-Wei Zhang
- School of Life Science and Biotechnology, Dalian University of Technology , Dalian 116024, Liaoning, China
| | - Xia Li
- School of Life Science and Biotechnology, Dalian University of Technology , Dalian 116024, Liaoning, China
| | - Wen-Long Sun
- School of Life Science and Biotechnology, Dalian University of Technology , Dalian 116024, Liaoning, China
| | - Yan Xing
- School of Life Science and Biotechnology, Dalian University of Technology , Dalian 116024, Liaoning, China
| | - Zhi-Long Xiu
- School of Life Science and Biotechnology, Dalian University of Technology , Dalian 116024, Liaoning, China
| | - Chun-Lin Zhuang
- School of Pharmacy, Second Military Medical University , 325 Guohe Road, Shanghai 200433, China
| | - Yue-Sheng Dong
- School of Life Science and Biotechnology, Dalian University of Technology , Dalian 116024, Liaoning, China
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210
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Yerlikaya S, Zengin G, Mollica A, Baloglu MC, Celik Altunoglu Y, Aktumsek A. A Multidirectional Perspective for Novel Functional Products: In vitro Pharmacological Activities and In silico Studies on Ononis natrix subsp. hispanica. Front Pharmacol 2017; 8:600. [PMID: 28919860 PMCID: PMC5585257 DOI: 10.3389/fphar.2017.00600] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Accepted: 08/21/2017] [Indexed: 12/12/2022] Open
Abstract
The genus Ononis has important value as traditional drugs and foods. In the present work, we aimed to assess the chemical profiles and biological effects of Ononis natrix subsp. hispanica extracts (ethyl acetate, methanol, and water). For chemical profile, total and individual phenolic components were detected. For biological effects, antioxidant (DPPH, ABTS, CUPRAC, FRAP, phosphomolybdenum, and metal chelating assays), enzyme inhibitory (against cholinesterase, tyrosinase, α-amylase and α-glucosidase), antimicrobial, DNA protection and cytotoxic abilities were tested. The predominant phenolics were apigenin, luteolin, and quercetin in the tested extracts. Generally, the ethyl acetate and methanol extracts were noted as the most active in the antioxidant and enzyme inhibitory assays. Water extract with different concentrations indicated high level of DNA protection activity. Methanol and ethyl acetate extracts showed antibacterial effect against to Staphylococcus aureus and Staphylococcus epidermidis strains. The cytotoxic effects of O. natrix subsp. hispanica extracts on the survival of HeLa and PC3 cells were determined by MTT cell viability assay. Water and methanol extracts caused initiation of apoptosis for PC3 cell line. Furthermore, molecular docking was performed to better understand interactions between dominant phenolic compounds and selected enzymes. Our results clearly indicate that O. natrix subsp. hispanica could be considered a potential candidate for designing novel pharmaceuticals, cosmeceuticals and nutraceuticals.
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Affiliation(s)
- Serife Yerlikaya
- Department of Genetics and Bioengineering, Faculty of Engineering and Architecture, Kastamonu UniversityKastamonu, Turkey
| | - Gokhan Zengin
- Department of Biology, Science Faculty, Selcuk UniversityKonya, Turkey
| | - Adriano Mollica
- Department of Pharmacy University "G. d'Annunzio" of Chieti-PescaraChieti, Italy
| | - Mehmet C Baloglu
- Department of Genetics and Bioengineering, Faculty of Engineering and Architecture, Kastamonu UniversityKastamonu, Turkey
| | - Yasemin Celik Altunoglu
- Department of Genetics and Bioengineering, Faculty of Engineering and Architecture, Kastamonu UniversityKastamonu, Turkey
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211
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Han L, Fang C, Zhu R, Peng Q, Li D, Wang M. Inhibitory effect of phloretin on α-glucosidase: Kinetics, interaction mechanism and molecular docking. Int J Biol Macromol 2017; 95:520-527. [DOI: 10.1016/j.ijbiomac.2016.11.089] [Citation(s) in RCA: 108] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Revised: 11/19/2016] [Accepted: 11/19/2016] [Indexed: 10/20/2022]
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212
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Qi YJ, Lu HN, Liang JX, Zhao YM, Wang XE, Jin NZ. Comparison of the molecular interactions of 7'-carboxyalkyl apigenin derivatives with S. cerevisiae α-glucosidase. Comput Biol Chem 2017; 67:182-193. [PMID: 28131019 DOI: 10.1016/j.compbiolchem.2017.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 12/09/2016] [Accepted: 01/16/2017] [Indexed: 11/26/2022]
Abstract
As one of the most investigated flavonoids, apigenin, is considered to be a strong α-glucosidase inhibitor. However, the clinical utility of apigenin is limited due to its low solubility. It was reported that the solubility and biological activity can be improved by introducing sole carboxyalkyl group into apigenin, especially the 7'-substitution. With the increase of length of the alkyl chain in carboxyalkyl group, B ring of the apigenin derivative is embedded much more deeply into the binding cavity while the carboxyalkyl stretches to the neighboring cavity. All of the terminal carboxyl groups form hydrogen bonding interactions easily with the surrounding polar amino acids, such as His239, Ser244, Arg312 and Asp349. Thus, the electron density values of the carbonyl in the carboxyl group become higher than the solution status due to the strong molecular interactions. In fact, electron densities of most of the chemical bonds are decreased after molecular docking procedure. On compared with the solution phase, however, dipole moments of most of these molecules are increased, and their vectors are reoriented distinctly in the active sites. It is noticed that all of the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) are distributed throughout the whole parent apigenin ring in solution phase, whereas the disappeared situation happened on the B rings of some molecules (II-IV) in the active site, leading to higher energy gaps.
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Affiliation(s)
- Y J Qi
- Department of Chemical Engineering, Northwest University for Nationalities, Lanzhou 730124, PR China.
| | - H N Lu
- Department of Life Sciences and Biological Engineering, Northwest University for Nationalities, Lanzhou 730124, PR China
| | - J X Liang
- Department of Chemical Engineering, Northwest University for Nationalities, Lanzhou 730124, PR China
| | - Y M Zhao
- Department of Chemical Engineering, Northwest University for Nationalities, Lanzhou 730124, PR China
| | - X E Wang
- Department of Chemical Engineering, Northwest University for Nationalities, Lanzhou 730124, PR China
| | - N Z Jin
- Gansu Province Computing Center, Lanzhou 730000, PR China
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