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Iqbal Z, Fauzia Farheen Zofair S, Ahmed S, Sharma M, Younus H, Mahmood R. Interaction of plant phenol vanillin with human hemoglobin: A spectroscopic and molecular docking study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 322:124831. [PMID: 39024790 DOI: 10.1016/j.saa.2024.124831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 07/12/2024] [Accepted: 07/13/2024] [Indexed: 07/20/2024]
Abstract
Vanillin is a phenolic aldehyde widely used as a flavouring agent in the food industry. Vanillin has many health benefits and has gained attention in pharmacological industries also, due to its antioxidant properties and non-toxic nature. The interaction of vanillin with human hemoglobin (hHb), an abundant tetrameric heme protein, was investigated by several spectroscopic techniques and molecular modeling methods. UV-visible spectra showed that the binding of vanillin to hHb induces structural changes due to alterations in the micro-environment of hHb. Vanillin quenches the intrinsic fluorescence of hHb by the dynamic mechanism, which was confirmed by both temperature dependent and time resolved fluorescence studies. Vanillin binds spontaneously to hHb at a single site and the binding is stabilized by hydrogen bonds and hydrophobic interactions. The circular dichroism spectra showed that the binding of vanillin altered the secondary structure of hHb due to change in its alpha-helical content. Molecular docking identified the amino acids of hHb involved in binding to vanillin and also that the free energy change of the binding reaction is -5.5 kcal/mol. Thus, our results indicate that vanillin binds spontaneously to hHb at a single site and alters its secondary structure. This will help in understanding the potential use of vanillin and related antioxidants as therapeutic agents in various hematological disorders.
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Affiliation(s)
- Zarmin Iqbal
- Department of Biochemistry, Aligarh Muslim University, Aligarh 202002, UP, India
| | - Syeda Fauzia Farheen Zofair
- Interdisciplinary Biotechnology Unit, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, UP, India
| | - Shahbaz Ahmed
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Monika Sharma
- Department of Biochemistry, Aligarh Muslim University, Aligarh 202002, UP, India
| | - Hina Younus
- Interdisciplinary Biotechnology Unit, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, UP, India
| | - Riaz Mahmood
- Department of Biochemistry, Aligarh Muslim University, Aligarh 202002, UP, India.
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Islam MR, Rauf A, Akash S, Sharker M, Mahreen M, Munira MAK, Dhar PS, Hemeg HA, Iriti M, Imran M. Targeted therapeutic management based on phytoconstituents for sickle cell anemia focusing on molecular mechanisms: Current trends and future perspectives. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2024; 133:155936. [PMID: 39128304 DOI: 10.1016/j.phymed.2024.155936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 03/28/2024] [Accepted: 08/03/2024] [Indexed: 08/13/2024]
Abstract
The global epidemic of Sickle cell anemia (SCA) is causing thousands of children to die. SCA, a genetic disorder affecting the hemoglobin-globin chain, affects millions globally. The primary physiological issue in these patients is the polymerization of sickle hemoglobin within their red blood cells (RBCs) during their deoxygenating state. The RBC undergoes a sickle shape due to the polymerization of mutant hemoglobin within it and membrane deformation during anoxic conditions. To prevent complications, it is essential to effectively stop the sickling of RBCs of the patients. Various medications have been studied for treating SCA patients, focusing on antisickling, γ-globulin induction, and antiplatelet action. Natural and synthetic anti-sickling agents can potentially reduce patient clinical morbidity. Numerous clinical trials focused on using natural remedies for the symptomatic therapy of SCA. Medicinal plants and phytochemical agents have antisickling properties. Recent studies on plant extracts' natural compounds have primarily focused on in vitro RBCs sickling studies, with limited data on in vivo studies. This review discussed the potential role of phytoconstituents in the management of SCA.
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Affiliation(s)
- Md Rezaul Islam
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Daffodil Smart City, Birulia, Savar, Dhaka 1216, Bangladesh
| | - Abdur Rauf
- Department of Chemistry, University of Swabi, Anbar 23561, Khyber Pakhtunkhwa, Pakistan.
| | - Shopnil Akash
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Daffodil Smart City, Birulia, Savar, Dhaka 1216, Bangladesh
| | - Muntasir Sharker
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Daffodil Smart City, Birulia, Savar, Dhaka 1216, Bangladesh
| | - Mashiat Mahreen
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Daffodil Smart City, Birulia, Savar, Dhaka 1216, Bangladesh
| | - Most Ayesha Khatun Munira
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Daffodil Smart City, Birulia, Savar, Dhaka 1216, Bangladesh
| | - Puja Sutro Dhar
- Department of Pharmacy, Faculty of Allied Health Sciences, Daffodil International University, Daffodil Smart City, Birulia, Savar, Dhaka 1216, Bangladesh
| | - Hassan A Hemeg
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, Taibah University, Al-Madinah Al-Monawara, Saudi Arabia
| | - Marcello Iriti
- Department of Biomedical, Surgical and Dental Sciences, University of Milan, via Celoria 2, 20133, Milan, Italy; National Interuniversity Consortium of Materials Science and Technology (INSTM), 50121 Firenze, Italy.
| | - Muhammad Imran
- Chemistry Department, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia
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Shu P, You G, Li W, Chen Y, Chu Z, Qin D, Wang Y, Zhou H, Zhao L. Cefmetazole sodium as an allosteric effector that regulates the oxygen supply efficiency of adult hemoglobin. J Biomol Struct Dyn 2024; 42:7442-7456. [PMID: 37555593 DOI: 10.1080/07391102.2023.2245043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 07/17/2023] [Indexed: 08/10/2023]
Abstract
Allosteric effectors play an important role in regulating the oxygen supply efficiency of hemoglobin for blood storage and disease treatment. However, allosteric effectors that are approved by the US FDA are limited. In this study, cefmetazole sodium (CS) was found to bind adult hemoglobin (HbA) from FDA library (1338 compounds) using surface plasmon resonance imaging high-throughput screening. Using surface plasmon resonance (SPR), the interaction between CS and HbA was verified. The oxygen dissociation curve of HbA after CS interaction showed a significant increase in P50 and theoretical oxygen-release capacity. Acid-base sensitivity (SI) exhibited a decreasing trend, although not significantly different. An oxygen dissociation assay indicated that CS accelerated HbA deoxygenation. Microfluidic modulated spectroscopy showed that CS changed the ratio of the alpha-helix to the beta-sheet of HbA. Molecular docking suggested CS bound to HbA's β-chains via hydrogen bonds, with key amino acids being N282, K225, H545, K625, K675, and V544.The results of molecular dynamics simulations (MD) revealed a stable orientation of the HbA-CS complex. CS did not significantly affect the P50 of bovine hemoglobin, possibly due to the lack of Valβ1 and Hisβ2, indicating that these were the crucial amino acids involved in HbA's oxygen affinity. Competition between the 2,3-Diphosphoglycerate (2,3-DPG) and CS in the HbA interaction was also determined by SPR, molecular docking and MD. In summary, CS could interact with HbA and regulate the oxygen supply efficiency via forming stable hydrogen bonds with the β-chains of HbA, and showed competition with 2,3-DPG.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Peilin Shu
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
| | - Guoxing You
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
| | - Weidan Li
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
| | - Yuzhi Chen
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
| | - Zongtang Chu
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
| | - Dong Qin
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
| | - Ying Wang
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
| | - Hong Zhou
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
| | - Lian Zhao
- Institute of Health Service and Transfusion Medicine, Academy of Military Medical Sciences, Academy of Military Science of the Chinese People's Liberation Army, Beijing, P.R. C
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Zhou X, Su W, Bao Q, Cui Y, Li X, Yang Y, Yang C, Wang C, Jiao L, Chen D, Huang J. Nitric Oxide Ameliorates the Effects of Hypoxia in Mice by Regulating Oxygen Transport by Hemoglobin. High Alt Med Biol 2024; 25:174-185. [PMID: 38743636 DOI: 10.1089/ham.2023.0044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2024] Open
Abstract
Xiaoying Zhou, Wenting Su, Quanwei Bao, Yu Cui, Xiaoxu Li, Yidong Yang, Chengzhong Yang, Chengyuan Wang, Li Jiao, Dewei Chen, and Jian Huang. Nitric oxide ameliorates the effects of hypoxia in mice by regulating oxygen transport by hemoglobin. High Alt Med Biol. 25:174-185, 2024.-Hypoxia is a common pathological and physiological phenomenon in ischemia, cancer, and strenuous exercise. Nitric oxide (NO) acts as an endothelium-derived relaxing factor in hypoxic vasodilation and serves as an allosteric regulator of hemoglobin (Hb). However, the ultimate effects of NO on the hematological system in vivo remain unknown, especially in extreme environmental hypoxia. Whether NO regulation of the structure of Hb improves oxygen transport remains unclear. Hence, we examined whether NO altered the oxygen affinity of Hb (Hb-O2 affinity) to protect extremely hypoxic mice. Mice were exposed to severe hypoxia with various concentrations of NO, and the survival time, exercise capacity, and other physical indexes were recorded. The survival time was prolonged in the 5 ppm NO (6.09 ± 1.29 minutes) and 10 ppm NO (6.39 ± 1.58 minutes) groups compared with the 0 ppm group (4.98 ± 1.23 minutes). Hypoxia of the brain was relieved, and the exercise exhaustion time was prolonged when mice inhaled 20 ppm NO (24.70 ± 6.87 minutes vs. 20.23 ± 6.51 minutes). In addition, the differences in arterial oxygen saturation (SO2%) (49.64 ± 7.29% vs. 42.90 ± 4.30%) and arteriovenous SO2% difference (25.14 ± 8.95% vs. 18.10 ± 6.90%) obviously increased. In ex vivo experiments, the oxygen equilibrium curve (OEC) left shifted as P50 decreased from 43.77 ± 2.49 mmHg (0 ppm NO) to 40.97 ± 1.40 mmHg (100 ppm NO) and 38.36 ± 2.78 mmHg (200 ppm NO). Furthermore, the Bohr effect of Hb was enhanced by the introduction of 200 ppm NO (-0.72 ± 0.062 vs.-0.65 ± 0.051), possibly allowing Hb to more easily offload oxygen in tissue at lower pH. The crystal structure reveals a greater distance between Asp94β-His146β in nitrosyl -Hb(NO-Hb), NO-HbβCSO93, and S-NitrosoHb(SNO-Hb) compared to tense Hb(T-Hb, 3.7 Å, 4.3 Å, and 5.8 Å respectively, versus 3.5 Å for T-Hb). Moreover, hydrogen bonds were less likely to form, representing a key limitation of relaxed Hb (R-Hb). Upon NO interaction with Hb, hydrogen bonds and salt bridges were less favored, facilitating relaxation. We speculated that NO ameliorated the effects of hypoxia in mice by promoting erythrocyte oxygen loading in the lung and offloading in tissues.
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Affiliation(s)
- Xiaoying Zhou
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Wenting Su
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Quanwei Bao
- Department of Emergency Medicine, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Yu Cui
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Xiaoxu Li
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Yidong Yang
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Chengzhong Yang
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Chengyuan Wang
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Li Jiao
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Dewei Chen
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
| | - Jian Huang
- Department of High Altitude Physiology and Pathology, College of High Altitude Military Medicine, Army Medical University, Chongqing, China
- High Altitude Medical Research Center, PLA, Chongqing, China
- Key Laboratory of High Altitude and Frigidzone Medical Surpport, PLA, Chongqing, China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Chongqing, China
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Sekyonda Z, An R, Goreke U, Man Y, Monchamp K, Bode A, Zhang Q, El-Gammal Y, Kityo C, Kalfa TA, Akkus O, Gurkan UA. Rapid measurement of hemoglobin-oxygen dissociation by leveraging Bohr effect and Soret band bathochromic shift. Analyst 2024; 149:2561-2572. [PMID: 38501195 PMCID: PMC11056771 DOI: 10.1039/d3an02071a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/24/2024] [Indexed: 03/20/2024]
Abstract
Oxygen (O2) binds to hemoglobin (Hb) in the lungs and is then released (dissociated) in the tissues. The Bohr effect is a physiological mechanism that governs the affinity of Hb for O2 based on pH, where a lower pH results in a lower Hb-O2 affinity and higher Hb-O2 dissociation. Hb-O2 affinity and dissociation are crucial for maintaining aerobic metabolism in cells and tissues. Despite its vital role in human physiology, Hb-O2 dissociation measurement is underutilized in basic research and in clinical laboratories, primarily due to the technical complexity and limited throughput of existing methods. We present a rapid Hb-O2 dissociation measurement approach by leveraging the Bohr effect and detecting the optical shift in the Soret band that corresponds to the light absorption by the heme group in Hb. This new method reduces Hb-O2 dissociation measurement time from hours to minutes. We show that Hb deoxygenation can be accelerated chemically at the optimal pH of 6.9. We show that time and pH-controlled deoxygenation of Hb results in rapid and distinct conformational changes in its tertiary structure. These molecular conformational changes are manifested as significant, detectable shifts in Hb's optical absorption spectrum, particularly in the characteristic Soret band (414 nm). We extensively validated the method by testing human blood samples containing normal Hb and Hb variants. We show that rapid Hb-O2 dissociation can be used to screen for and detect Hb-O2 affinity disorders and to evaluate the function and efficacy of Hb-modifying therapies. The ubiquity of optical absorption spectrophotometers positions this approach as an accessible, rapid, and accurate Hb-O2 dissociation measurement method for basic research and clinical use. We anticipate this method's broad adoption will democratize the diagnosis and prognosis of Hb disorders, such as sickle cell disease. Further, this method has the potential to transform the research and development of new targeted and genome-editing-based therapies that aim to modify or improve Hb-O2 affinity.
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Affiliation(s)
- Zoe Sekyonda
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
| | - Ran An
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 10900 Euclid Ave., Glennan Building 616B, Cleveland, OH, 44106, USA.
| | - Utku Goreke
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 10900 Euclid Ave., Glennan Building 616B, Cleveland, OH, 44106, USA.
| | - Yuncheng Man
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 10900 Euclid Ave., Glennan Building 616B, Cleveland, OH, 44106, USA.
| | - Karamoja Monchamp
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 10900 Euclid Ave., Glennan Building 616B, Cleveland, OH, 44106, USA.
- Division of Hematology and Oncology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Allison Bode
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 10900 Euclid Ave., Glennan Building 616B, Cleveland, OH, 44106, USA.
- Division of Hematology and Oncology, University Hospitals Cleveland Medical Center, Cleveland, OH, USA
| | - Qiaochu Zhang
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 10900 Euclid Ave., Glennan Building 616B, Cleveland, OH, 44106, USA.
| | - Yasmin El-Gammal
- Division of Hematology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Cissy Kityo
- The Joint Clinical Research Center, Kampala, Uganda
| | - Theodosia A Kalfa
- Division of Hematology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Ozan Akkus
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 10900 Euclid Ave., Glennan Building 616B, Cleveland, OH, 44106, USA.
- Department of Orthopedics, Case Western Reserve University, Cleveland, OH, USA
| | - Umut A Gurkan
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, USA
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, 10900 Euclid Ave., Glennan Building 616B, Cleveland, OH, 44106, USA.
- Department of Orthopedics, Case Western Reserve University, Cleveland, OH, USA
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH, USA
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Majid MA, Ullah H, Alshehri AM, Tabassum R, Aleem A, Khan AUR, Batool Z, Nazir A, Bibi I. Development of novel polymer haemoglobin based particles as an antioxidant, antibacterial and an oxygen carrier agents. Sci Rep 2024; 14:3031. [PMID: 38321082 PMCID: PMC10847508 DOI: 10.1038/s41598-024-53548-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 02/01/2024] [Indexed: 02/08/2024] Open
Abstract
This innovative work aims to develop highly biocompatible and degradable nanoparticles by encapsulating haemoglobin (Hb) within poly-ε-caprolactone for novel biomedical applications. We used a modified double emulsion solvent evaporation method to fabricate the particles. A Scanning electron microscope (SEM) characterized them for surface morphology. Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet-visible spectroscopies (UV-visible) elucidated preserved chemical and biological structure of encapsulated haemoglobin. The airproof equilibrium apparatus obtained the oxygen-carrying capacity and P50 values. The DPPH assay assessed free radical scavenging potential. The antibacterial properties were observed using four different bacterial strains by disk diffusion method. The MTT assay investigates the cytotoxic effects on mouse fibroblast cultured cell lines (L-929). The MTT assay showed that nanoparticles have no toxicity over large concentrations. The well-preserved structure of Hb within particles, no toxicity, high oxygen affinity, P50 value, and IC50 values open the area of new research, which may be used as artificial oxygen carriers, antioxidant, and antibacterial agents, potential therapeutic agents as well as drug carrier particles to treat the cancerous cells. The novelty of this work is the antioxidant and antibacterial properties of developed nanoparticles are not been reported yet. Results showed that the prepared particles have strong antioxidant and antibacterial potential.
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Affiliation(s)
- Muhammad Abdul Majid
- Biophotonics Imaging Techniques Laboratory, Institute of Physics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Hafeez Ullah
- Biophotonics Imaging Techniques Laboratory, Institute of Physics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan.
| | - Ali Mohammad Alshehri
- Department of Physics, King Khalid University, P.O. Box 9004, 61413, Abha, Saudi Arabia
| | - Rukhsana Tabassum
- Institute of Chemistry, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Abdul Aleem
- Biophotonics Imaging Techniques Laboratory, Institute of Physics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Asad Ur Rehman Khan
- Biophotonics Imaging Techniques Laboratory, Institute of Physics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Zahida Batool
- Biophotonics Imaging Techniques Laboratory, Institute of Physics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Aalia Nazir
- Biophotonics Imaging Techniques Laboratory, Institute of Physics, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
| | - Ismat Bibi
- Institute of Chemistry, The Islamia University of Bahawalpur, Bahawalpur, Pakistan
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7
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Omar AM, Abdulmalik O, El-Say KM, Ghatge MS, Cyril-Olutayo M, Paredes S, Al-Awadh M, El-Araby ME, Safo MK. Targeted modification of furan-2-carboxaldehydes into Michael acceptor analogs yielded long-acting hemoglobin modulators with dual antisickling activities. Chem Biol Drug Des 2024; 103:e14371. [PMID: 37798397 DOI: 10.1111/cbdd.14371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/10/2023] [Accepted: 09/26/2023] [Indexed: 10/07/2023]
Abstract
Sickle cell disease (SCD) is the most common genetic disorder, affecting millions of people worldwide. Aromatic aldehydes, which increase the oxygen affinity of human hemoglobin to prevent polymerization of sickle hemoglobin and inhibit red blood cell (RBC) sickling, have been the subject of keen interest for the development of effective treatment against SCD. However, the aldehyde functional group metabolic instability has severly hampered their development, except for voxelotor, which was approved in 2019 for SCD treatment. To improve the metabolic stability of aromatic aldehydes, we designed and synthesized novel molecules by incorporating Michael acceptor reactive centers into the previously clinically studied aromatic aldehyde, 5-hydroxymethylfurfural (5-HMF). Eight such derivatives, referred to as MMA compounds were synthesized and studied for their functional and biological activities. Unlike 5-HMF, which forms Schiff-base interaction with αVal1 nitrogen of hemoglobin, the MMA compounds covalently interacted with βCys93, as evidenced by reverse-phase HPLC and disulfide exchange reaction, explaining their RBC sickling inhibitory activities, which at 2 mM and 5 mM, range from 0% to 21% and 9% to 64%, respectively. Additionally, the MMA compounds showed a second mechanism of sickling inhibition (12%-41% and 13%-62% at 2 mM and 5 mM, respectively) by directly destabilizing the sickle hemoglobin polymer. In vitro studies demonstrated sustained pharmacologic activities of the compounds compared to 5-HMF. These findings hold promise for advancing SCD therapeutics.
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Affiliation(s)
- Abdelsattar M Omar
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
- Center for Artificial Intelligence in Precision Medicines, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Osheiza Abdulmalik
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Khalid M El-Say
- Department of Pharmaceutics, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mohini S Ghatge
- Department of Medicinal Chemistry, School of Pharmacy and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Mojisola Cyril-Olutayo
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Steven Paredes
- Department of Medicinal Chemistry, School of Pharmacy and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Mohammed Al-Awadh
- Department of Medicinal Chemistry, School of Pharmacy and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Moustafa E El-Araby
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
- Center for Artificial Intelligence in Precision Medicines, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Martin K Safo
- Department of Medicinal Chemistry, School of Pharmacy and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, Virginia, USA
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Nadimifar M, Ghourchian H, Hosta-Rigau L, Moosavi-Movahedi AA. Structural and functional alterations of polydopamine-coated hemoglobin: New insights for the development of successful oxygen carriers. Int J Biol Macromol 2023; 253:127275. [PMID: 37804889 DOI: 10.1016/j.ijbiomac.2023.127275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/09/2023]
Abstract
One of the major factors that is currently hindering the development of hemoglobin (Hb)-based oxygen carriers (HBOCs) is the autoxidation of Hb into nonfunctional methemoglobin. Modification with polydopamine (PDA), which is a biocompatible free radical scavenger has shown the ability to protect Hb against oxidation. Due to its tremendous potential in the development of successful HBOCs, herein, we conduct a thorough evaluation of the effect of PDA on the stability, aggregation, structure and function of the underlying Hb. By UV-vis spectrometry we show that PDA can prevent Hb's aggregation while thermal denaturation studies indicate that, although PDA coating resulted in a lower midpoint transition temperature, it was also able to protect the protein from full denaturation. These results are further corroborated by differential scanning calorimetry. Circular dichroism reveals that PDA can promote changes in Hb's secondary structure while, by UV-vis spectroscopy, we show that PDA also interacts with the porphyrin complex located in Hb's hydrophobic pocket. Last but not least, affinity studies show that PDA-coated Hb has a higher capability for oxygen release. Such an effect is further enhanced at lower pH. Importantly, through molecular docking simulations we provide a plausible explanation for the observed experimental results.
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Affiliation(s)
| | | | - Leticia Hosta-Rigau
- DTU Health Tech, Center for Nanomedicine and Theranostics, Technical University of Denmark, Nils Koppels Allé, Building 423, 2800 Kgs. Lyngby, Denmark.
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9
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Nong Q, Chen B, Huang Y, Li Y, Wang Y, Liu L, He B, Luan T, Hu L, Jiang G. Identification of lead-binding proteins as carriers and potential molecular targets associated with systolic blood pressure. CHEMOSPHERE 2023; 341:140138. [PMID: 37696478 DOI: 10.1016/j.chemosphere.2023.140138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 08/31/2023] [Accepted: 09/08/2023] [Indexed: 09/13/2023]
Abstract
Lead (Pb) exposure is well recognized as a significant environmental factor associated with the high incidence of cardiovascular diseases. However, the carriers and molecular targets of Pb in human blood remain to be understood, especially for a real Pb exposure scenario. In this study, a total of 350 blood samples were collected from the smelting workers and systematically analyzed using metallomics and metalloproteomics approaches. The results showed that the majority of Pb (∼99.4%) could be presented in the blood cells. Pb in the cytoplasm of blood cells accounted for approximately 83.1% of the total blood Pb, with nearly half of Pb being bound to proteins. Pb-binding proteins in the blood of workers were identified as hemoglobin, catalase, haptoglobin, δ-aminolevulinic acid dehydratase, and peroxiredoxin-2. Multiple linear regression analysis demonstrated that higher levels of Pb bound to proteins (Mix-bound Pb and Protein-bound Pb) were positively associated with higher systolic blood pressure (p < 0.05). However, the association between blood lead level, Pb levels in the blood cells and systolic blood pressure was not observed (p > 0.05). This study suggested that Pb bound to proteins could be a suitable biomarker for indicating the potential risk of occupational hypertension.
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Affiliation(s)
- Qiying Nong
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; State Key Lab of Bioresource and Biocontrol, School of Life Science, Sun Yat-sen University, Guangzhou, 510275, China; Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou, 510300, China
| | - Baowei Chen
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-sen University, Zhuhai, 519082, China
| | - Yongshun Huang
- Guangdong Province Hospital for Occupational Disease Prevention and Treatment, Guangzhou, 510300, China
| | - Yiling Li
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Yuanyuan Wang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Lihong Liu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Bin He
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
| | - Tiangang Luan
- State Key Lab of Bioresource and Biocontrol, School of Life Science, Sun Yat-sen University, Guangzhou, 510275, China; Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou, 510006, China
| | - Ligang Hu
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China; Institute of Environment and Health, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310000, China.
| | - Guibin Jiang
- State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China
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10
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Li X, Li H, Lai K, Miao J. The Effect of Glucose on the Interaction of Bisphenol A and Bovine Hemoglobin Characterized by Spectroscopic and Molecular Docking Techniques. Int J Mol Sci 2023; 24:14708. [PMID: 37834156 PMCID: PMC10572490 DOI: 10.3390/ijms241914708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Revised: 09/23/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
The interaction mechanism of hemoglobin (Hb) with bisphenol A (BPA) in diabetic patients and the difference with healthy people have been studied using spectroscopic and molecular docking techniques at several glucose (Glc) concentration, with bovine hemoglobin (BHb) instead of Hb. It is found that Glc can interact with BHb-BPA and affect its molecular structure, resulting in an altered microenvironment for tyrosine (Tyr) and tryptophan (Trp) in BHb-BPA. It is also found that Glc can bind to BHb alone, and its effect on the molecular structure of BHb is weaker than that on the structure of BHb in BHb-BPA complex. The results of circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR) indicate that Glc causes an increase in the content of the α-helix and a decrease in that of the β-sheet of BHb-BPA by 1.5-1.9% and 3.1%, respectively. The results of molecular docking show that Glc binds to BHb-BPA through hydrogen and hydrophobic bonds, and the position of binding differs from that of Glc binding to BHb alone, which may be attributed to the fact that BPA affects the protein molecular structure of BHb and has an effect on the binding of BHb to Glc. This study provides some theoretical basis for the mechanism of BPA toxicity in vivo for people with different blood glucose levels.
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Affiliation(s)
- Xianheng Li
- College of Food Science and Technology, Shanghai Ocean University, No. 999 Hucheng Huan Road, Lingang New City, Shanghai 201306, China; (X.L.); (H.L.)
| | - Huan Li
- College of Food Science and Technology, Shanghai Ocean University, No. 999 Hucheng Huan Road, Lingang New City, Shanghai 201306, China; (X.L.); (H.L.)
| | - Keqiang Lai
- College of Food Science and Technology, Shanghai Ocean University, No. 999 Hucheng Huan Road, Lingang New City, Shanghai 201306, China; (X.L.); (H.L.)
- Engineering Research Center of Food Thermal-Processing Technology, Shanghai Ocean University, Shanghai 201306, China
| | - Junjian Miao
- College of Food Science and Technology, Shanghai Ocean University, No. 999 Hucheng Huan Road, Lingang New City, Shanghai 201306, China; (X.L.); (H.L.)
- Engineering Research Center of Food Thermal-Processing Technology, Shanghai Ocean University, Shanghai 201306, China
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11
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Devi Tulsiyan K, Rani Prusty M, Biswal HS. Effect of Choline Amino Acid-Based Ionic Liquids on Stability and Structure of Hemoglobin. Chemphyschem 2023; 24:e202300201. [PMID: 37272734 DOI: 10.1002/cphc.202300201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 06/05/2023] [Accepted: 06/05/2023] [Indexed: 06/06/2023]
Abstract
Ionic liquids (ILs) can stabilize or destabilize proteins, which motivates us to examine their effect on hemoglobin. The native state of hemoglobin (Hb) is disrupted at different physical conditions such as pressure, temperature, and solvents. Herein, we have monitored the stability of Hb in a nontoxic and biocompatible IL, i. e., choline amino acid-based Ils (ChAAILs), using various spectroscopic techniques like UV-Vis and fluorescence spectroscopy, circular dichroism (CD), and isothermal titration calorimetry (ITC) measurements. It was observed that Hb stays neither in its native state nor in its fully denatured state; rather, it achieves an intermediate state in the presence of ChAAILs. The research on the intermediate state of Hb is still unexplored. Research has been pursued to find a suitable ligand or IL that can stabilize the intermediate state of Hb. In that context, ChAAILs are among the best choices. Molecular docking studies unravel the binding of ChAAILs with Hb. The obtained binding energies of the docked complex are -7.2 kcal/mol and -8.7 kcal/mol for binding of Hb with [Chl][Gly] and [Chl][Met], respectively, which was in line with the ITC results. The quantum chemical calculations show that H-bond plays a significant role for the interaction between Hb and ChAAILs.
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Affiliation(s)
- Kiran Devi Tulsiyan
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), Jatni, Khurda, Bhubaneswar, 752050, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400094, India
| | - Mallika Rani Prusty
- School of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Berhampur, Berhampur, Odisha, 760010, India
| | - Himansu S Biswal
- School of Chemical Sciences, National Institute of Science Education and Research (NISER), Jatni, Khurda, Bhubaneswar, 752050, India
- Homi Bhabha National Institute, Training School Complex, Anushakti Nagar, Mumbai, 400094, India
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12
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Donkor AK, Pagare PP, Mughram MHAL, Safo MK. X-ray crystallography and sickle cell disease drug discovery-a tribute to Donald Abraham. Front Mol Biosci 2023; 10:1136970. [PMID: 37293554 PMCID: PMC10244664 DOI: 10.3389/fmolb.2023.1136970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 05/15/2023] [Indexed: 06/10/2023] Open
Abstract
X-ray crystallography and structure-based drug discovery have played a major role in the discovery of antisickling agents that target hemoglobin (Hb) for the treatment of sickle cell disease (SCD). Sickle cell disease, the most common inherited hematologic disorder, occurs as a result of a single point mutation of βGlu6 in normal human adult hemoglobin (HbA) to βVal6 in sickle hemoglobin (HbS). The disease is characterized by polymerization of HbS and sickling of red blood cells (RBCs), leading to several secondary pathophysiologies, including but not limited to vaso-occlusion, hemolytic anemia, oxidative stress, inflammation, stroke, pain crisis, and organ damage. Despite the fact that SCD was the first disease to have its molecular basis established, the development of therapies was for a very long time a challenge and took several decades to find therapeutic agents. The determination of the crystal structure of Hb by Max Perutz in the early 60s, and the pioneering X-ray crystallography research by Donald J. Abraham in the early 80s, which resulted in the first structures of Hb in complex with small molecule allosteric effectors of Hb, gave much hope that structure-based drug discovery (SBDD) could be used to accelerate development of antisickling drugs that target the primary pathophysiology of hypoxia-induced HbS polymerization to treat SCD. This article, which is dedicated to Donald J. Abraham, briefly reviews structural biology, X-ray crystallography and structure-based drug discovery from the perspective of Hb. The review also presents the impact of X-ray crystallography in SCD drug development using Hb as a target, emphasizing the major and important contributions by Don Abraham in this field.
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13
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Salam S, Arif A, Nabi F, Mahmood R. Molecular docking and biophysical studies on the interaction between thiram and human hemoglobin. J Mol Struct 2023. [DOI: 10.1016/j.molstruc.2022.134188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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14
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Li S, Sun W, Ouyang M, Yu B, Chen Y, Wang Y, Zhou D. Hemoglobin‐Related Biomaterials and their Applications. ADVANCED NANOBIOMED RESEARCH 2022. [DOI: 10.1002/anbr.202200103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Affiliation(s)
- Shaobing Li
- Department of Ultrasonic Diagnosis Department of Orthopedics Zhujiang Hospital Southern Medical University Guangzhou 510282 P.R. China
- NMPA Key Laboratory for Research and Evaluation of Drug Metabolism Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical Sciences Southern Medical University Guangzhou 510515 P.R. China
| | - Wei Sun
- Department of Ultrasonic Diagnosis Department of Orthopedics Zhujiang Hospital Southern Medical University Guangzhou 510282 P.R. China
- NMPA Key Laboratory for Research and Evaluation of Drug Metabolism Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical Sciences Southern Medical University Guangzhou 510515 P.R. China
| | - Min Ouyang
- NMPA Key Laboratory for Research and Evaluation of Drug Metabolism Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical Sciences Southern Medical University Guangzhou 510515 P.R. China
| | - Bo Yu
- Department of Ultrasonic Diagnosis Department of Orthopedics Zhujiang Hospital Southern Medical University Guangzhou 510282 P.R. China
| | - Yan Chen
- Department of Ultrasonic Diagnosis Department of Orthopedics Zhujiang Hospital Southern Medical University Guangzhou 510282 P.R. China
| | - Yupeng Wang
- Department of Ultrasonic Diagnosis Department of Orthopedics Zhujiang Hospital Southern Medical University Guangzhou 510282 P.R. China
| | - Dongfang Zhou
- Department of Ultrasonic Diagnosis Department of Orthopedics Zhujiang Hospital Southern Medical University Guangzhou 510282 P.R. China
- NMPA Key Laboratory for Research and Evaluation of Drug Metabolism Guangdong Provincial Key Laboratory of New Drug Screening School of Pharmaceutical Sciences Southern Medical University Guangzhou 510515 P.R. China
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15
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Stuhr R, Bayer P, von Wangelin AJ. The Diverse Modes of Oxygen Reactivity in Life & Chemistry. CHEMSUSCHEM 2022; 15:e202201323. [PMID: 36214486 PMCID: PMC10100308 DOI: 10.1002/cssc.202201323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 10/08/2022] [Indexed: 06/16/2023]
Abstract
Oxygen is a molecule of utmost importance in our lives. Beside its vital role for the respiration and sustaining of organisms, oxygen is involved in numerous chemical and physical processes. Upon combination of the different forms of molecular oxygen species with various activation modes, substrates, and reaction conditions an extremely wide chemical space can be covered that enables rich applications of diverse oxygenation processes. This Review provides an instructive overview of the individual properties and reactivities of oxygen species and illustrates their importance in nature, everyday life, and in the context of chemical synthesis.
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Affiliation(s)
- Robin Stuhr
- Department of ChemistryUniversity of HamburgMartin-Luther-King Platz 620146HamburgGermany
| | - Patrick Bayer
- Pantheon AustriaThermo Fisher ScientificSt. Peter Str. 254020LinzAustria
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16
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Balasco N, Paladino A, Graziano G, D'Abramo M, Vitagliano L. Atomic-Level View of the Functional Transition in Vertebrate Hemoglobins: The Case of Antarctic Fish Hbs. J Chem Inf Model 2022; 62:3874-3884. [PMID: 35930673 PMCID: PMC9400108 DOI: 10.1021/acs.jcim.2c00727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Tetrameric hemoglobins (Hbs) are prototypal systems for studies aimed at unveiling basic structure-function relationships as well as investigating the molecular/structural basis of adaptation of living organisms to extreme conditions. However, a chronological analysis of decade-long studies conducted on Hbs is illuminating on the difficulties associated with the attempts of gaining functional insights from static structures. Here, we applied molecular dynamics (MD) simulations to explore the functional transition from the T to the R state of the hemoglobin of the Antarctic fish Trematomus bernacchii (HbTb). Our study clearly demonstrates the ability of the MD technique to accurately describe the transition of HbTb from the T to R-like states, as shown by a number of global and local structural indicators. A comparative analysis of the structural states that HbTb assumes in the simulations with those detected in previous MD analyses conducted on HbA (human Hb) highlights interesting analogies (similarity of the transition pathway) and differences (distinct population of intermediate states). In particular, the ability of HbTb to significantly populate intermediate states along the functional pathway explains the observed propensity of this protein to assume these structures in the crystalline state. It also explains some functional data reported on the protein that indicate the occurrence of other functional states in addition to the canonical R and T ones. These findings are in line with the emerging idea that the classical two-state view underlying tetrameric Hb functionality is probably an oversimplification and that other structural states play important roles in these proteins. The ability of MD simulations to accurately describe the functional pathway in tetrameric Hbs suggests that this approach may be effectively applied to unravel the molecular and structural basis of Hbs exhibiting peculiar functional properties as a consequence of the environmental adaptation of the host organism.
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Affiliation(s)
- Nicole Balasco
- Institute of Molecular Biology and Pathology, CNR c/o Dep. Chemistry, University of Rome, Sapienza, P.le A. Moro 5, 00185 Rome, Italy
| | - Antonella Paladino
- Institute of Biostructures and Bioimaging, CNR, Via Pietro Castellino 111, 80131 Naples, Italy
| | - Giuseppe Graziano
- Department of Science and Technology, University of Sannio, via Francesco de Sanctis snc, Benevento 82100, Italy
| | - Marco D'Abramo
- Department of Chemistry, University of Rome Sapienza, P.le A.Moro 5, 00185 Rome, Italy
| | - Luigi Vitagliano
- Institute of Biostructures and Bioimaging, CNR, Via Pietro Castellino 111, 80131 Naples, Italy
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17
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Binder JL, Berendzen J, Stevens AO, He Y, Wang J, Dokholyan NV, Oprea TI. AlphaFold illuminates half of the dark human proteins. Curr Opin Struct Biol 2022; 74:102372. [PMID: 35439658 PMCID: PMC10669925 DOI: 10.1016/j.sbi.2022.102372] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 03/02/2022] [Accepted: 03/13/2022] [Indexed: 01/05/2023]
Abstract
We investigate the use of confidence scores to evaluate the accuracy of a given AlphaFold (AF2) protein model for drug discovery. Prediction of accuracy is improved by not considering confidence scores below 80 due to the effects of disorder. On a set of recent crystal structures, 95% are likely to have accurate folds. Conformational discordance in the training set has a much more significant effect on accuracy than sequence divergence. We propose criteria for models and residues that are possibly useful for virtual screening. Based on these criteria, AF2 provides models for half of understudied (dark) human proteins and two-thirds of residues in those models.
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Affiliation(s)
- Jessica L Binder
- Translational Informatics Division, Department of Internal Medicine, University of New Mexico, Albuquerque, NM 87131, USA. https://twitter.com/@jessicamaine
| | - Joel Berendzen
- Translational Informatics Division, Department of Internal Medicine, University of New Mexico, Albuquerque, NM 87131, USA
| | - Amy O Stevens
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Yi He
- Translational Informatics Division, Department of Internal Medicine, University of New Mexico, Albuquerque, NM 87131, USA; Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Jian Wang
- Department of Pharmacology, Department of Biochemistry and Molecular Biology, Penn State University College of Medicine, Hershey, PA 17033, USA
| | - Nikolay V Dokholyan
- Department of Pharmacology, Department of Biochemistry and Molecular Biology, Penn State University College of Medicine, Hershey, PA 17033, USA; Department of Chemistry and Department of Biomedical Engineering, Pennsylvania State University, University Park, PA 16802, United States
| | - Tudor I Oprea
- Translational Informatics Division, Department of Internal Medicine, University of New Mexico, Albuquerque, NM 87131, USA; UNM Comprehensive Cancer Center, Albuquerque, NM, USA; Department of Rheumatology and Inflammation Research, Institute of Medicine, Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
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18
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Alhashimi RT, Ghatge MS, Donkor AK, Deshpande TM, Anabaraonye N, Alramadhani D, Danso-Danquah R, Huang B, Zhang Y, Musayev FN, Abdulmalik O, Safo MK. Design, Synthesis, and Antisickling Investigation of a Nitric Oxide-Releasing Prodrug of 5HMF for the Treatment of Sickle Cell Disease. Biomolecules 2022; 12:696. [PMID: 35625623 PMCID: PMC9138457 DOI: 10.3390/biom12050696] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/05/2022] [Accepted: 05/10/2022] [Indexed: 02/02/2023] Open
Abstract
5-hydroxyfurfural (5HMF), an allosteric effector of hemoglobin (Hb) with an ability to increase Hb affinity for oxygen has been studied extensively for its antisickling effect in vitro and in vivo, and in humans for the treatment of sickle cell disease (SCD). One of the downstream pathophysiologies of SCD is nitric oxide (NO) deficiency, therefore increasing NO (bio)availability is known to mitigate the severity of SCD symptoms. We report the synthesis of an NO-releasing prodrug of 5HMF (5HMF-NO), which in vivo, is expected to be bio-transformed into 5HMF and NO, with concomitant therapeutic activities. In vitro studies showed that when incubated with whole blood, 5HMF-NO releases NO, as anticipated. When incubated with sickle blood, 5HMF-NO formed Schiff base adduct with Hb, increased Hb affinity for oxygen, and prevented hypoxia-induced erythrocyte sickling, which at 1 mM concentration were 16%, 10% and 27%, respectively, compared to 21%, 18% and 21% for 5HMF. Crystal structures of 5HMF-NO with Hb showed 5HMF-NO bound to unliganded (deoxygenated) Hb, while the hydrolyzed product, 5HMF bound to liganded (carbonmonoxy-ligated) Hb. Our findings from this proof-of-concept study suggest that the incorporation of NO donor group to 5HMF and analogous molecules could be a novel beneficial strategy to treat SCD and warrants further detailed in vivo studies.
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Affiliation(s)
- Rana T. Alhashimi
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
| | - Mohini S. Ghatge
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
| | - Akua K. Donkor
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
| | | | - Nancy Anabaraonye
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA; (N.A.); (O.A.)
| | - Dina Alramadhani
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
| | - Richmond Danso-Danquah
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
| | - Boshi Huang
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
| | - Yan Zhang
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
| | - Faik N. Musayev
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
| | - Osheiza Abdulmalik
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA; (N.A.); (O.A.)
| | - Martin K. Safo
- Department of Medicinal Chemistry and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298, USA; (R.T.A.); (M.S.G.); (A.K.D.); (D.A.); (R.D.-D.); (B.H.); (Y.Z.); (F.N.M.)
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19
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Pagare PP, Rastegar A, Abdulmalik O, Omar AM, Zhang Y, Fleischman A, Safo MK. Modulating hemoglobin allostery for treatment of sickle cell disease: current progress and intellectual property. Expert Opin Ther Pat 2022; 32:115-130. [PMID: 34657559 PMCID: PMC8881396 DOI: 10.1080/13543776.2022.1994945] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2021] [Accepted: 10/14/2021] [Indexed: 02/03/2023]
Abstract
INTRODUCTION Sickle cell disease (SCD) is a debilitating inherited disorder that affects millions worldwide. Four novel SCD therapeutics have been approved, including the hemoglobin (Hb) modulator Voxelotor. AREAS COVERED This review provides an overview of discovery efforts toward modulating Hb allosteric behavior as a treatment for SCD, with a focus on aromatic aldehydes that increase Hb oxygen affinity to prevent the primary pathophysiology of hypoxia-induce erythrocyte sickling. EXPERT OPINION The quest to develop small molecules, especially aromatic aldehydes, to modulate Hb allosteric properties for SCD began in the 1970s; however, early promise was dogged by concerns that stalled support for research efforts. Persistent efforts eventually culminated in the discovery of the anti-sickling agent 5-HMF in the 2000s, and reinvigorated interest that led to the discovery of vanillin analogs, including Voxelotor, the first FDA approved Hb modulator for the treatment of SCD. With burgeoning interest in the field of Hb modulation, there is a growing landscape of intellectual property, including drug candidates at various stages of preclinical and clinical investigations. Hb modulators could provide not only the best chance for a highly effective oral therapy for SCD, especially in the under-developed world, but also a way to treat a variety of other human conditions.
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Affiliation(s)
- Piyusha P. Pagare
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298
| | - Aref Rastegar
- The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298
| | - Osheiza Abdulmalik
- Division of Hematology, The Children’s Hospital of Philadelphia, PA 19104
| | - Abdelsattar M. Omar
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Alsulaymanyah, Jeddah 21589, Saudi Arabia
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo 11884, Egypt
| | - Yan Zhang
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298
| | | | - Martin K. Safo
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298
- The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA 23298
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Cho HS, Schotte F, Stadnytskyi V, Anfinrud P. Time-resolved X-ray scattering studies of proteins. Curr Opin Struct Biol 2021; 70:99-107. [PMID: 34175665 PMCID: PMC8530917 DOI: 10.1016/j.sbi.2021.05.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 05/01/2021] [Accepted: 05/10/2021] [Indexed: 11/24/2022]
Abstract
Time-resolved small- and wide-angle X-ray scattering studies of proteins in solution based on the pump-probe approach unveil structural information from intermediates over a broad range of length and time scales. In spite of the promise of this methodology, only a fraction of the wealth of information encoded in scattering data has been extracted in studies performed thus far. Here, we discuss the methodology, summarize results from recent time-resolved X-ray scattering studies, and examine the potential to extract additional information from these scattering curves.
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Affiliation(s)
- Hyun Sun Cho
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, MD, 20892-0520, USA
| | - Friedrich Schotte
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, MD, 20892-0520, USA
| | - Valentyn Stadnytskyi
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, MD, 20892-0520, USA
| | - Philip Anfinrud
- Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Bethesda, MD, 20892-0520, USA.
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21
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Gaurav M, Natesh A, Arundhati A, Mariam D. Biochemical aspects of hemoglobin-xenobiotic interactions and their implications in drug discovery. Biochimie 2021; 191:154-163. [PMID: 34474139 DOI: 10.1016/j.biochi.2021.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 07/27/2021] [Accepted: 08/17/2021] [Indexed: 11/18/2022]
Abstract
Hemoglobin, a homodimeric globular protein, is found predominantly in red blood cells and in a small amount in blood plasma. Along with binding to certain native molecules, it also interacts with various xenobiotics. The present review aims at studying these interactions and the resultant tangible impact on the structure and function of the protein if any. The review also encompasses various analytical and computational approaches which are routinely used to study these interactions. A detailed discussion on types of interaction exhibited by individual xenobiotics has been included herein. Additionally, the effects of xenobiotic binding on the oxygen carrying capacity of hemoglobin have been reviewed. These insights would be of great value in drug design and discovery. Envisaging probable interactions of designed ligands with hemoglobin would help improvise the process of drug development. This would also open up new avenues for studying hemoglobin-mediated drug delivery.
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Affiliation(s)
- Mehta Gaurav
- Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, India
| | - Ahuja Natesh
- Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, India
| | - Abhyankar Arundhati
- Shri Vile Parle Kelavani Mandal's Dr Bhanuben Nanavati College of Pharmacy, India
| | - Degani Mariam
- Department of Pharmaceutical Sciences and Technology, Institute of Chemical Technology, India.
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22
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Lucero García Rojas EY, Villanueva C, Bond RA. Hypoxia Inducible Factors as Central Players in the Pathogenesis and Pathophysiology of Cardiovascular Diseases. Front Cardiovasc Med 2021; 8:709509. [PMID: 34447792 PMCID: PMC8382733 DOI: 10.3389/fcvm.2021.709509] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Accepted: 07/09/2021] [Indexed: 01/01/2023] Open
Abstract
Cardiovascular (CV) diseases are the major cause of death in industrialized countries. The main function of the CV system is to deliver nutrients and oxygen to all tissues. During most CV pathologies, oxygen and nutrient delivery is decreased or completely halted. Several mechanisms, including increased oxygen transport and delivery, as well as increased blood flow are triggered to compensate for the hypoxic state. If the compensatory mechanisms fail to sufficiently correct the hypoxia, irreversible damage can occur. Thus, hypoxia plays a central role in the pathogenesis and pathophysiology of CV diseases. Hypoxia inducible factors (HIFs) orchestrate the gene transcription for hundreds of proteins involved in erythropoiesis, glucose transport, angiogenesis, glycolytic metabolism, reactive oxygen species (ROS) handling, cell proliferation and survival, among others. The overall regulation of the expression of HIF-dependent genes depends on the severity, duration, and location of hypoxia. In the present review, common CV diseases were selected to illustrate that HIFs, and proteins derived directly or indirectly from their stabilization and activation, are related to the development and perpetuation of hypoxia in these pathologies. We further classify CV diseases into acute and chronic hypoxic states to better understand the temporal relevance of HIFs in the pathogenesis, disease progression and clinical outcomes of these diseases. We conclude that HIFs and their derived factors are fundamental in the genesis and progression of CV diseases. Understanding these mechanisms will lead to more effective treatment strategies leading to reduced morbidity and mortality.
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Affiliation(s)
| | - Cleva Villanueva
- Instituto Politecnico Nacional, Escuela Superior de Medicina, Mexico City, Mexico
| | - Richard A Bond
- Department of Pharmacology and Pharmaceutical Sciences, University of Houston, Houston, TX, United States
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23
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Cumulative Damage: Cell Death in Posthemorrhagic Hydrocephalus of Prematurity. Cells 2021; 10:cells10081911. [PMID: 34440681 PMCID: PMC8393895 DOI: 10.3390/cells10081911] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/23/2021] [Accepted: 07/25/2021] [Indexed: 12/19/2022] Open
Abstract
Globally, approximately 11% of all infants are born preterm, prior to 37 weeks’ gestation. In these high-risk neonates, encephalopathy of prematurity (EoP) is a major cause of both morbidity and mortality, especially for neonates who are born very preterm (<32 weeks gestation). EoP encompasses numerous types of preterm birth-related brain abnormalities and injuries, and can culminate in a diverse array of neurodevelopmental impairments. Of note, posthemorrhagic hydrocephalus of prematurity (PHHP) can be conceptualized as a severe manifestation of EoP. PHHP impacts the immature neonatal brain at a crucial timepoint during neurodevelopment, and can result in permanent, detrimental consequences to not only cerebrospinal fluid (CSF) dynamics, but also to white and gray matter development. In this review, the relevant literature related to the diverse mechanisms of cell death in the setting of PHHP will be thoroughly discussed. Loss of the epithelial cells of the choroid plexus, ependymal cells and their motile cilia, and cellular structures within the glymphatic system are of particular interest. Greater insights into the injuries, initiating targets, and downstream signaling pathways involved in excess cell death shed light on promising areas for therapeutic intervention. This will bolster current efforts to prevent, mitigate, and reverse the consequential brain remodeling that occurs as a result of hydrocephalus and other components of EoP.
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Ahmed TA, El-Say KM, Abd-Allah FI, Omar AM, El-Araby ME, Muhammad YA, Pagare PP, Zhang Y, Mohmmad KA, Abdulmalik O, Safo MK. Improving the Solubility and Oral Bioavailability of a Novel Aromatic Aldehyde Antisickling Agent (PP10) for the Treatment of Sickle Cell Disease. Pharmaceutics 2021; 13:1148. [PMID: 34452107 PMCID: PMC8401948 DOI: 10.3390/pharmaceutics13081148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 07/15/2021] [Accepted: 07/23/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Aromatic aldehydes, with their ability to increase the oxygen affinity of sickle hemoglobin, have become important therapeutic agents for sickle cell disease (SCD). One such compound, voxelotor, was recently approved for SCD treatment. Methyl 6-((2-formyl-3-hydroxyphenoxy)methyl) picolinate (PP10) is another promising aromatic aldehyde, recently reported by our group. Like voxelotor, PP10 exhibits O2-dependent antisickling activity, but, unlike voxelotor, PP10 shows unique O2-independent antisickling effect. PP10, however, has limited solubility. This study therefore aimed to develop oral and parenteral formulations to improve PP10 solubility and bioavailability. METHODS Oral drug tablets with 2-hydroxypropyl beta cyclodextrin (HP-β-CD), polyvinylpyrrolidone, or Eudragit L100-55 PP10-binary system, and an intravenous (IV) formulation with d-α-tocopherol polyethylene glycol 1000 succinate (TPGS) or HP-β-CD, were developed. The pharmacokinetic behavior of the formulations was studied in Sprague-Dawley rats. PP10, a methylester, and its acid metabolite were also studied in vitro with sickle whole blood to determine their effect on Hb modification, Hb oxygen affinity, and sickle red blood cell inhibition. RESULTS Aqueous solubility of PP10 was enhanced ~5 times with the HP-β-CD binary system, while the TPGS aqueous micelle formulation was superior, with a drug concentration of 0.502 ± 0.01 mg/mL and a particle size of 26 ± 3 nm. The oral tablets showed relative and absolute bioavailabilities of 173.4% and 106.34%, respectively. The acid form of PP10 appeared to dominate in vivo, although both PP10 forms demonstrated pharmacologic effect. CONCLUSION Oral and IV formulations of PP10 were successfully developed using HP-β-CD binary system and TPGS aqueous micelles, respectively, resulting in significantly improved solubility and bioavailability.
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Affiliation(s)
- Tarek A. Ahmed
- Department of Pharmaceutics, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Al-Azhar University, Cairo 11884, Egypt;
| | - Khalid M. El-Say
- Department of Pharmaceutics, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia;
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Al-Azhar University, Cairo 11884, Egypt;
| | - Fathy I. Abd-Allah
- Department of Pharmaceutics and Industrial Pharmacy, Faculty of Pharmacy, Al-Azhar University, Cairo 11884, Egypt;
| | - Abdelsattar M. Omar
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia; (A.M.O.); (M.E.E.-A.); (Y.A.M.); (K.A.M.)
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo 11884, Egypt
| | - Moustafa E. El-Araby
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia; (A.M.O.); (M.E.E.-A.); (Y.A.M.); (K.A.M.)
| | - Yosra A. Muhammad
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia; (A.M.O.); (M.E.E.-A.); (Y.A.M.); (K.A.M.)
| | - Piyusha P. Pagare
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298, USA; (P.P.P.); (Y.Z.); (M.K.S.)
| | - Yan Zhang
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298, USA; (P.P.P.); (Y.Z.); (M.K.S.)
| | - Khadijah A. Mohmmad
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia; (A.M.O.); (M.E.E.-A.); (Y.A.M.); (K.A.M.)
| | - Osheiza Abdulmalik
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA;
| | - Martin K. Safo
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, VA 23298, USA; (P.P.P.); (Y.Z.); (M.K.S.)
- Development, School of Pharmacy, The Institute for Structural Biology, Drug Discovery, Virginia Commonwealth University, Richmond, VA 23298, USA
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Abri-Mehraban F, Zargar SJ, Salarizadeh N. The effect of glucose on doxorubicin and human hemoglobin interaction: Characterization with spectroscopic techniques. Int J Biol Macromol 2021; 181:193-201. [PMID: 33771549 DOI: 10.1016/j.ijbiomac.2021.03.130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2021] [Revised: 03/20/2021] [Accepted: 03/22/2021] [Indexed: 11/24/2022]
Abstract
The application of doxorubicin (DOX), which is the most effective anticancer drug, is limited due to its cardiac toxicity. The study of DOX-hemoglobin (Hb) interaction has biochemical and toxicological importance. Understanding the Hb-DOX interaction in the presence of glucose (Glc), as the main blood sugar, can be advantageous for clinical implications. In this study, the structural changes imposed by DOX on Hb in the presence of various concentrations of Glc were investigated using different methods such as UV-Vis, fluorescence, and circular dichroism (CD) spectroscopy. The results obtained by the spectroscopic techniques revealed that the hyperchromic effect, which was observed after treating Hb with DOX, was relieved in the presence of Glc. Based on the results of fluorescence spectroscopy, some of the photons emitted from the tryptophan (Trp) residues were quenched due to DOX binding. Since the Trp residues were exposed, the intrinsic fluorescence of Hb increased but the residues might not have been competent for DOX binding anymore. The results of the CD technique demonstrated that the levels of the alpha-helix structure were significantly reduced when Hb was simultaneously treated with DOX and Glc. Thermal stability studies revealed that the melting temperature of Hb increased in the presence of Glc alone. However, the thermal stability of Hb decreased in the presence of Glc/DOX (combined). Since the concentration of Glc in diabetic patients is significantly higher than in healthy individuals, the toxic effects of DOX, due to its interaction with Hb, may be different in healthy and diabetic subjects.
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Affiliation(s)
- Fatemeh Abri-Mehraban
- Department of Cell & Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran
| | - Seyed Jalal Zargar
- Department of Cell & Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran.
| | - Navvabeh Salarizadeh
- Department of Cell & Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran, Iran
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26
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Pagare PP, Ghatge MS, Chen Q, Musayev FN, Venitz J, Abdulmalik O, Zhang Y, Safo MK. Exploration of Structure-Activity Relationship of Aromatic Aldehydes Bearing Pyridinylmethoxy-Methyl Esters as Novel Antisickling Agents. J Med Chem 2020; 63:14724-14739. [PMID: 33205981 DOI: 10.1021/acs.jmedchem.0c01287] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Aromatic aldehydes elicit their antisickling effects primarily by increasing the affinity of hemoglobin (Hb) for oxygen (O2). However, challenges related to weak potency and poor pharmacokinetic properties have hampered their development to treat sickle cell disease (SCD). Herein, we report our efforts to enhance the pharmacological profile of our previously reported compounds. These compounds showed enhanced effects on Hb modification, Hb-O2 affinity, and sickling inhibition, with sustained pharmacological effects in vitro. Importantly, some compounds exhibited unusually high antisickling activity despite moderate effects on the Hb-O2 affinity, which we attribute to an O2-independent antisickling activity, in addition to the O2-dependent activity. Structural studies are consistent with our hypothesis, which revealed the compounds interacting strongly with the polymer-stabilizing αF-helix could potentially weaken the polymer. In vivo studies with wild-type mice demonstrated significant pharmacologic effects. Our structure-based efforts have identified promising leads to be developed as novel therapeutic agents for SCD.
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Affiliation(s)
- Piyusha P Pagare
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Mohini S Ghatge
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States.,The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Qiukan Chen
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, United States
| | - Faik N Musayev
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States.,The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Jurgen Venitz
- Department of Pharmaceutics, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Osheiza Abdulmalik
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, United States
| | - Yan Zhang
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States.,The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Martin K Safo
- Department of Medicinal Chemistry, Virginia Commonwealth University, Richmond, Virginia 23298, United States.,The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
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VZHE-039, a novel antisickling agent that prevents erythrocyte sickling under both hypoxic and anoxic conditions. Sci Rep 2020; 10:20277. [PMID: 33219275 PMCID: PMC7679387 DOI: 10.1038/s41598-020-77171-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 11/06/2020] [Indexed: 12/20/2022] Open
Abstract
Sickle cell disease (SCD) results from a hemoglobin (Hb) mutation βGlu6 → βVal6 that changes normal Hb (HbA) into sickle Hb (HbS). Under hypoxia, HbS polymerizes into rigid fibers, causing red blood cells (RBCs) to sickle; leading to numerous adverse pathological effects. The RBC sickling is made worse by the low oxygen (O2) affinity of HbS, due to elevated intra-RBC concentrations of the natural Hb effector, 2,3-diphosphoglycerate. This has prompted the development of Hb modifiers, such as aromatic aldehydes, with the intent of increasing Hb affinity for O2 with subsequent prevention of RBC sickling. One such molecule, Voxelotor was recently approved by U.S. FDA to treat SCD. Here we report results of a novel aromatic aldehyde, VZHE-039, that mimics both the O2-dependent and O2-independent antisickling properties of fetal hemoglobin. The latter mechanism of action—as elucidated through crystallographic and biological studies—is likely due to disruption of key intermolecular contacts necessary for stable HbS polymer formation. This dual antisickling mechanism, in addition to VZHE-039 metabolic stability, has translated into significantly enhanced and sustained pharmacologic activities. Finally, VZHE-039 showed no significant inhibition of several CYPs, demonstrated efficient RBC partitioning and high membrane permeability, and is not an efflux transporter (P-gp) substrate.
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28
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Omar AM, Abdulmalik O, Ghatge MS, Muhammad YA, Paredes SD, El-Araby ME, Safo MK. An Investigation of Structure-Activity Relationships of Azolylacryloyl Derivatives Yielded Potent and Long-Acting Hemoglobin Modulators for Reversing Erythrocyte Sickling. Biomolecules 2020; 10:E1508. [PMID: 33147875 PMCID: PMC7693414 DOI: 10.3390/biom10111508] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 10/25/2020] [Accepted: 10/30/2020] [Indexed: 12/27/2022] Open
Abstract
Aromatic aldehydes that bind to sickle hemoglobin (HbS) to increase the protein oxygen affinity and/or directly inhibit HbS polymer formation to prevent the pathological hypoxia-induced HbS polymerization and the subsequent erythrocyte sickling have for several years been studied for the treatment of sickle cell disease (SCD). With the exception of Voxelotor, which was recently approved by the U.S. Food and Drug Administration (FDA) to treat the disease, several other promising antisickling aromatic aldehydes have not fared well in the clinic because of metabolic instability of the aldehyde moiety, which is critical for the pharmacologic activity of these compounds. Over the years, our group has rationally developed analogs of aromatic aldehydes that incorporate a stable Michael addition reactive center that we hypothesized would form covalent interactions with Hb to increase the protein affinity for oxygen and prevent erythrocyte sickling. Although, these compounds have proven to be metabolically stable, unfortunately they showed weak to no antisickling activity. In this study, through additional targeted modifications of our lead Michael addition compounds, we have discovered other novel antisickling agents. These compounds, designated MMA, bind to the α-globin and/or β-globin to increase Hb affinity for oxygen and concomitantly inhibit erythrocyte sickling with significantly enhanced and sustained pharmacologic activities in vitro.
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Affiliation(s)
- Abdelsattar M. Omar
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Alsulaymanyah, Jeddah 21589, Saudi Arabia; (Y.A.M.); (M.E.E.-A.)
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo 11884, Egypt
| | - Osheiza Abdulmalik
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA;
| | - Mohini S. Ghatge
- Department of Medicinal Chemistry, School of Pharmacy and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA; (M.S.G.); (S.D.P.)
| | - Yosra A. Muhammad
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Alsulaymanyah, Jeddah 21589, Saudi Arabia; (Y.A.M.); (M.E.E.-A.)
| | - Steven D. Paredes
- Department of Medicinal Chemistry, School of Pharmacy and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA; (M.S.G.); (S.D.P.)
| | - Moustafa E. El-Araby
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, King Abdulaziz University, Alsulaymanyah, Jeddah 21589, Saudi Arabia; (Y.A.M.); (M.E.E.-A.)
| | - Martin K. Safo
- Department of Medicinal Chemistry, School of Pharmacy and Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA 23219, USA; (M.S.G.); (S.D.P.)
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Iqbal H, Yang T, Li T, Zhang M, Ke H, Ding D, Deng Y, Chen H. Serum protein-based nanoparticles for cancer diagnosis and treatment. J Control Release 2020; 329:997-1022. [PMID: 33091526 DOI: 10.1016/j.jconrel.2020.10.030] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 10/13/2020] [Accepted: 10/15/2020] [Indexed: 12/15/2022]
Abstract
Serum protein as naturally essential biomacromolecules has recently emerged as a versatile carrier for diagnostic and therapeutic drug delivery for cancer nanomedicine with superior biocompatibility, improved pharmacokinetics and enhanced targeting capacity. A variety of serum proteins have been utilized for drug delivery, mainly including albumin, ferritin/apoferritin, transferrin, low-density lipoprotein, high-density lipoprotein and hemoglobin. As evidenced by the success of paclitaxel-bound albumin nanoparticles (AbraxaneTM), serum protein-based nanoparticles have gained attractive attentions for precise biological design and potential clinical application. In this review, we summarize the general design strategies, targeting mechanisms and recent development of serum protein-based nanoparticles in the field of cancer nanomedicine. Moreover, we also concisely specify the current challenges to be addressed for a bright future of serum protein-based nanomedicines.
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Affiliation(s)
- Haroon Iqbal
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China
| | - Tao Yang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China
| | - Ting Li
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China
| | - Miya Zhang
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China
| | - Hengte Ke
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China
| | - Dawei Ding
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China
| | - Yibin Deng
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China.
| | - Huabing Chen
- Jiangsu Key Laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences, Soochow University, Suzhou 215123, China; State Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, China.
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30
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Powell SM, Thomas LM, Richter-Addo GB. The nitrosoamphetamine metabolite is accommodated in the active site of human hemoglobin: Spectroscopy and crystal structure. J Inorg Biochem 2020; 213:111262. [PMID: 33049600 DOI: 10.1016/j.jinorgbio.2020.111262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 09/09/2020] [Accepted: 09/21/2020] [Indexed: 11/17/2022]
Abstract
Amphetamine-based (Amph) drugs are metabolized in humans to their hydroxylamine (AmphNHOH) and nitroso (AmphNO) derivatives. The latter metabolites are known to bind to the Fe centers of cytochrome P450 and other heme enzymes to inhibit their activities. Although these AmphNHOH/AmphNO metabolites are present in vivo, their interactions with the blood protein hemoglobin (Hb) and the muscle protein (Mb) have been largely discounted due to a perception that the relatively small heme active sites of Hb and Mb will not be able to accommodate the large AmphNO group. We report the 2.15 Å resolution X-ray crystal structure of the AmphNO adduct of adult human hemoglobin as the Hb [α-FeIII(H2O)][β-FeII(AmphNO)] derivative. We show that the binding of AmphNO to the β subunit is enabled by an E helix movement and stabilization of ligand binding by H-bonding with the distal His63 residue. We also observe an AmphNHOH group in the Xe2 pocket in close proximity to the α heme site in this derivative. Additionally, UV-vis spectroscopy was used to characterize this and related wt and mutant Mb adducts. Importantly, our X-ray crystal structure of this Hb-nitrosoamphetamine complex represents the first crystal structure of a wild-type heme protein adduct of any amphetamine metabolite. Our results provide a framework for further studies of AmphNHOH/AmphNO interactions with Hb and Mb as viable processes that potentially contribute to the overall biological inorganic chemistry of amphetamine drugs.
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Affiliation(s)
- Samantha M Powell
- Price Family Foundation Institute of Structural Biology, and Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, United States of America
| | - Leonard M Thomas
- Price Family Foundation Institute of Structural Biology, and Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, United States of America
| | - George B Richter-Addo
- Price Family Foundation Institute of Structural Biology, and Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, OK 73019, United States of America.
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Abstract
Oxygen affinity to haemoglobin is indicated by the p50 value (pO2 at 50% O2Hb) and critically determines cellular oxygen availability. Although high Hb-O2 affinity can cause tissue hypoxia under conditions of well O2 saturated blood, individual differences in p50 are commonly not considered in clinical routine. Here, we investigated the diversity in Hb-O2 affinity in the context of physiological relevance. Oxyhaemoglobin dissociation curves (ODCs) of 60 volunteers (18–40 years, both sexes, either endurance trained or untrained) were measured at rest and after maximum exercise (VO2max) test. At rest, p50 values of all participants ranged over 7 mmHg. For comparison, right shift of ODC after VO2max test, representing the maximal physiological range to release oxygen to the tissue, indicated a p50 difference of up to 10 mmHg. P50 at rest differs significantly between women and men, with women showing lower Hb-O2 affinity that is determined by higher 2,3-BPG and BPGM levels. Regular endurance exercise did not alter baseline Hb-O2 affinity. Thus, p50 diversity is already high at baseline level and needs to be considered under conditions of impaired tissue oxygenation. For fast prediction of Hb-O2 affinity by blood gas analysis, only venous but not capillary blood samples can be recommended.
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Szczesny-Malysiak E, Dybas J, Blat A, Bulat K, Kus K, Kaczmarska M, Wajda A, Malek K, Chlopicki S, Marzec KM. Irreversible alterations in the hemoglobin structure affect oxygen binding in human packed red blood cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118803. [PMID: 32738251 DOI: 10.1016/j.bbamcr.2020.118803] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/02/2020] [Accepted: 07/24/2020] [Indexed: 01/06/2023]
Abstract
The ability of hemoglobin (Hb) to transport respiratory gases is directly linked to its quaternary structure properties and reversible changes between T (tense) and R (relax) state. In this study we demonstrated that packed red blood cells (pRBCs) storage resulted in a gradual increase in the irreversible changes in the secondary and quaternary structures of Hb, with subsequent impairment of the T↔R transition. Such alteration was associated with the presence of irreversibly settled in the relaxed form, quaternary structure of Hb, which we termed R'. On the secondary structure level, disordered protein organization involved formation of β-sheets and a decrease in α-helices related to the aggregation process stabilized by strong intermolecular hydrogen bonding. Compensatory changes in RBCs metabolism launched to preserve reductive microenvironment were disclosed as an activation of nicotinamide adenine dinucleotide phosphate (NADPH) production and increased reduced to oxidized glutathione (GSH/GSSG) ratio. For the first time we showed the relationship between secondary structure changes and the occurrence of newly discovered R', which through an artificial increase in oxyhemoglobin level altered Hb ability to bind and release oxygen.
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Affiliation(s)
- Ewa Szczesny-Malysiak
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
| | - Jakub Dybas
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
| | - Aneta Blat
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland; Faculty of Chemistry, Jagiellonian University, 2 Gronostajowa Str., 30-387 Krakow, Poland.
| | - Katarzyna Bulat
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
| | - Kamil Kus
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
| | - Magdalena Kaczmarska
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
| | - Aleksandra Wajda
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland; Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Mickiewicza 30, 30-059 Krakow, Poland.
| | - Kamilla Malek
- Faculty of Chemistry, Jagiellonian University, 2 Gronostajowa Str., 30-387 Krakow, Poland.
| | - Stefan Chlopicki
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland; Chair of Pharmacology, Jagiellonian University Medical College, Grzegorzecka 16, 31-531 Krakow, Poland.
| | - Katarzyna M Marzec
- Jagiellonian Center for Experimental Therapeutics, Jagiellonian University, 14 Bobrzynskiego St., 30-348 Krakow, Poland.
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Abazari O, Shafaei Z, Divsalar A, Eslami-Moghadam M, Ghalandari B, Saboury AA, Moradi A. Interaction of the synthesized anticancer compound of the methyl-glycine 1,10-phenanthroline platinum nitrate with human serum albumin and human hemoglobin proteins by spectroscopy methods and molecular docking. JOURNAL OF THE IRANIAN CHEMICAL SOCIETY 2020. [DOI: 10.1007/s13738-020-01879-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
Human hemoglobin is the textbook example of the stereochemistry of an allosteric protein and of the exquisite control that a protein can exert over ligand binding. However, the fundamental basis by which the protein facilitates the ligand movement remains unknown. In this study, we used cryogenic X-ray crystallography and a high-repetition pulsed laser irradiation technique to elucidate the atomic details of ligand migration processes in hemoglobin after photolysis of the bound CO. Our data clarify the distinct CO migration pathways in the individual subunits of hemoglobin and unravel the functional roles of the internal cavities and neighboring amino acid residues in ligand exit and entry. Our results also demonstrate the high gas permeability and porosity of hemoglobin, facilitating O2 delivery. Hemoglobin is one of the best-characterized proteins with respect to structure and function, but the internal ligand diffusion pathways remain obscure and controversial. Here we captured the CO migration processes in the tense (T), relaxed (R), and second relaxed (R2) quaternary structures of human hemoglobin by crystallography using a high-repetition pulsed laser technique at cryogenic temperatures. We found that in each quaternary structure, the photodissociated CO molecules migrate along distinct pathways in the α and β subunits by hopping between the internal cavities with correlated side chain motions of large nonpolar residues, such as α14Trp(A12), α105Leu(G12), β15Trp(A12), and β71Phe(E15). We also observe electron density evidence for the distal histidine [α58/β63His(E7)] swing-out motion regardless of the quaternary structure, although less evident in α subunits than in β subunits, suggesting that some CO molecules have escaped directly through the E7 gate. Remarkably, in T-state Fe(II)-Ni(II) hybrid hemoglobins in which either the α or β subunits contain Ni(II) heme that cannot bind CO, the photodissociated CO molecules not only dock at the cavities in the original Fe(II) subunit, but also escape from the protein matrix and enter the cavities in the adjacent Ni(II) subunit even at 95 K, demonstrating the high gas permeability and porosity of the hemoglobin molecule. Our results provide a comprehensive picture of ligand movements in hemoglobin and highlight the relevance of cavities, nonpolar residues, and distal histidines in facilitating the ligand migration.
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Shibayama N. Allosteric transitions in hemoglobin revisited. Biochim Biophys Acta Gen Subj 2020; 1864:129335. [DOI: 10.1016/j.bbagen.2019.03.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 03/27/2019] [Accepted: 03/30/2019] [Indexed: 12/19/2022]
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Abstract
This chapter reviews how allosteric (heterotrophic) effectors and natural mutations impact hemoglobin (Hb) primary physiological function of oxygen binding and transport. First, an introduction about the structure of Hb is provided, including the ensemble of tense and relaxed Hb states and the dynamic equilibrium of Hb multistate. This is followed by a brief review of Hb variants with altered Hb structure and oxygen binding properties. Finally, a review of different endogenous and exogenous allosteric effectors of Hb is presented with particular emphasis on the atomic interactions of synthetic ligands with altered allosteric function of Hb that could potentially be harnessed for the treatment of diseases.
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Affiliation(s)
- Mostafa H Ahmed
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23219, USA
| | - Mohini S Ghatge
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23219, USA.,Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA, 23219, USA
| | - Martin K Safo
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23219, USA. .,Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, Richmond, VA, 23219, USA.
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Mavridis IM, Yannakopoulou K. Porphyrinoid-Cyclodextrin Assemblies in Biomedical Research: An Update. J Med Chem 2019; 63:3391-3424. [PMID: 31808344 DOI: 10.1021/acs.jmedchem.9b01069] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Porphyrinoids, well-known cofactors in fundamental processes of life, have stimulated interest as synthetic models of natural systems and integral components of photodynamic therapy, but their utilization is compromised by self-aggregation in aqueous media. The capacity of cyclodextrins to include hydrophobic molecules in their cavity provides porphyrinoids with a protective environment against oxidation and the ability to disperse efficiently in biological fluids. Moreover, engineered cyclodextrin-porphyrinoid assemblies enhance the photodynamic abilities of porphyrinoids, can carry chemotherapeutics for synergistic modalities, and can be enriched with functions including cell recognition, tissue penetration, and imaging. This Perspective includes synthetic porphyrinoid-cyclodextrin models of proteins participating in fundamental processes, such as enzymatic catalysis, respiration, and electron transfer. In addition, since porphyrinoid-cyclodextrin systems comprise third generation photosensitizers, recent developments for their utilization in photomedicine, that is, multimodal therapy for cancer (e.g., PDT, PTT) and antimicrobial treatment, and eventually in biocompatible therapeutic or diagnostic platforms for next-generation nanomedicine and theranostics are discussed.
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Affiliation(s)
- Irene M Mavridis
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos", Patriarchou Gregoriou & 27 Neapoleos Str., Agia Paraskevi, Attiki 15341, Greece
| | - Konstantina Yannakopoulou
- Institute of Nanoscience and Nanotechnology, National Center for Scientific Research "Demokritos", Patriarchou Gregoriou & 27 Neapoleos Str., Agia Paraskevi, Attiki 15341, Greece
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38
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Omar AM, David T, Pagare PP, Ghatge MS, Chen Q, Mehta A, Zhang Y, Abdulmalik O, Naghi AH, El-Araby ME, Safo MK. Structural modification of azolylacryloyl derivatives yields a novel class of covalent modifiers of hemoglobin as potential antisickling agents. MEDCHEMCOMM 2019; 10:1900-1906. [PMID: 32206236 PMCID: PMC7069400 DOI: 10.1039/c9md00291j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 08/15/2019] [Indexed: 01/01/2023]
Abstract
The intracellular polymerization and the concomitant sickling processes, central to the pathology of sickle cell disease, can be mitigated by increasing the oxygen affinity of sickle hemoglobin (HbS). Attempts to develop azolylacryloyl derivatives to covalently interact with βCys93 and destabilize the low-O2-affinity T-state (deoxygenated) HbS to the polymer resistant high-O2-affinity R-state (liganded) HbS were only partially successful. This was likely due to the azolylacryloyls carboxylate moiety directing the compounds to also bind in the central water cavity of deoxygenated Hb and stabilizing the T-state. We now report a second generation of KAUS compounds (KAUS-28, KAUS-33, KAUS-38, and KAUS-39) without the carboxylate moiety designed to bind exclusively to βCys93. As expected, the compounds showed reactivity with both free amino acid l-Cys and the Hb βCys93. At 2 mM concentrations, the compounds demonstrated increased Hb affinity for oxygen (6% to 15%) in vitro, while the previously reported imidazolylacryloyl carboxylate derivative, KAUS-15 only showed 4.5% increase. The increased O2 affinity effects were sustained through the experimental period of 12 h for KAUS-28, KAUS-33, and KAUS-38, suggesting conserved pharmacokinetic profiles. When incubated at 2 mM with red blood cells from patients with homozygous SS, the compounds inhibited erythrocyte sickling by 5% to 9%, respectively in correlation with the increase Hb-O2 affinity. These values compare to 2% for KAUS-15. When tested with healthy mice, KAUS-38 showed very low toxicity.
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Affiliation(s)
- A M Omar
- Department of Pharmaceutical Chemistry , Faculty of Pharmacy , King Abdulaziz University , Alsulaymanyah , Jeddah 21589 , Saudi Arabia .
- Department of Pharmaceutical Chemistry , Faculty of Pharmacy , Al-Azhar University , Cairo 11884 , Egypt
| | - T David
- Department of Medicinal Chemistry , School of Pharmacy and Institute for Structural Biology , Drug Discovery and Development , Virginia Commonwealth University , Richmond , VA 23219 , USA .
| | - P P Pagare
- Department of Medicinal Chemistry , School of Pharmacy and Institute for Structural Biology , Drug Discovery and Development , Virginia Commonwealth University , Richmond , VA 23219 , USA .
| | - M S Ghatge
- Department of Medicinal Chemistry , School of Pharmacy and Institute for Structural Biology , Drug Discovery and Development , Virginia Commonwealth University , Richmond , VA 23219 , USA .
| | - Q Chen
- Division of Hematology , The Children's Hospital of Philadelphia , PA 19104 , USA
| | - A Mehta
- Department of Medicinal Chemistry , School of Pharmacy and Institute for Structural Biology , Drug Discovery and Development , Virginia Commonwealth University , Richmond , VA 23219 , USA .
| | - Y Zhang
- Department of Medicinal Chemistry , School of Pharmacy and Institute for Structural Biology , Drug Discovery and Development , Virginia Commonwealth University , Richmond , VA 23219 , USA .
| | - O Abdulmalik
- Division of Hematology , The Children's Hospital of Philadelphia , PA 19104 , USA
| | - A H Naghi
- Department of Pharmaceutical Chemistry , Faculty of Pharmacy , King Abdulaziz University , Alsulaymanyah , Jeddah 21589 , Saudi Arabia .
| | - M E El-Araby
- Department of Pharmaceutical Chemistry , Faculty of Pharmacy , King Abdulaziz University , Alsulaymanyah , Jeddah 21589 , Saudi Arabia .
| | - M K Safo
- Department of Medicinal Chemistry , School of Pharmacy and Institute for Structural Biology , Drug Discovery and Development , Virginia Commonwealth University , Richmond , VA 23219 , USA .
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Aharoni R, Tobi D. Dynamical comparison between myoglobin and hemoglobin. Proteins 2018; 86:1176-1183. [PMID: 30183107 DOI: 10.1002/prot.25598] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 08/22/2018] [Accepted: 08/31/2018] [Indexed: 01/29/2023]
Abstract
Myoglobin and hemoglobin are globular hemeproteins, when the former is a monomer and the latter a heterotetramer. Despite the structural similarity of myoglobin to α and β subunits of hemoglobin, there is a functional difference between the two proteins, owing to the quaternary structure of hemoglobin. The effect of the quaternary structure of hemoglobin on the intrinsic dynamics of its subunits is explored by dynamical comparison of the two proteins. Anisotropic Network Model modes of motion were calculated for hemoglobin and myoglobin. Dynamical comparison between the proteins was performed using global and local Anisotropic Network Model mode alignment algorithms based on the algorithms of Smith-Waterman and Needleman-Wunsch for sequence comparison. The results indicate that the quaternary structure of hemoglobin substantially alters the intrinsic dynamics of its subunits, an effect that may contribute to the functional difference between the two proteins. Local dynamics similarity between the proteins is still observed at the major exit route of the ligand.
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Affiliation(s)
- Rotem Aharoni
- Department of Molecular Biology, Ariel University, Ariel, Israel
| | - Dror Tobi
- Department of Molecular Biology, Ariel University, Ariel, Israel.,Department of Computer Sciences, Ariel University, Ariel, Israel
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40
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Deshpande TM, Pagare PP, Ghatge MS, Chen Q, Musayev FN, Venitz J, Zhang Y, Abdulmalik O, Safo MK. Rational modification of vanillin derivatives to stereospecifically destabilize sickle hemoglobin polymer formation. Acta Crystallogr D Struct Biol 2018; 74:956-964. [PMID: 30289405 PMCID: PMC6173052 DOI: 10.1107/s2059798318009919] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/10/2018] [Indexed: 11/10/2022] Open
Abstract
Increasing the affinity of hemoglobin for oxygen represents a feasible and promising therapeutic approach for sickle cell disease by mitigating the primary pathophysiological event, i.e. the hypoxia-induced polymerization of sickle hemoglobin (Hb S) and the concomitant erythrocyte sickling. Investigations on a novel synthetic antisickling agent, SAJ-310, with improved and sustained antisickling activity have previously been reported. To further enhance the biological effects of SAJ-310, a structure-based approach was employed to modify this compound to specifically inhibit Hb S polymer formation through interactions which perturb the Hb S polymer-stabilizing αF-helix, in addition to primarily increasing the oxygen affinity of hemoglobin. Three compounds, TD-7, TD-8 and TD-9, were synthesized and studied for their interactions with hemoglobin at the atomic level, as well as their functional and antisickling activities in vitro. X-ray crystallographic studies with liganded hemoglobin in complex with TD-7 showed the predicted mode of binding, although the interaction with the αF-helix was not as strong as expected. These findings provide important insights and guidance towards the development of molecules that would be expected to bind and make stronger interactions with the αF-helix, resulting in more efficacious novel therapeutics for sickle cell disease.
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Affiliation(s)
- Tanvi M. Deshpande
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
- The Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
| | - Piyusha P. Pagare
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
| | - Mohini S. Ghatge
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
- The Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
| | - Qiukan Chen
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Faik N. Musayev
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
- The Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
| | - Jurgen Venitz
- Department of Pharmaceutics, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
| | - Yan Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
| | - Osheiza Abdulmalik
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Martin K. Safo
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
- The Institute for Structural Biology, Drug Discovery and Development, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23219, USA
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Das S, Bora N, Rohman MA, Sharma R, Jha AN, Singha Roy A. Molecular recognition of bio-active flavonoids quercetin and rutin by bovine hemoglobin: an overview of the binding mechanism, thermodynamics and structural aspects through multi-spectroscopic and molecular dynamics simulation studies. Phys Chem Chem Phys 2018; 20:21668-21684. [PMID: 30101248 DOI: 10.1039/c8cp02760a] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The binding of two bio-active flavonoids, quercetin and rutin, with bovine hemoglobin (BHb) was investigated by multi-spectroscopic and computational (molecular docking and molecular dynamics simulation) studies. The two flavonoids were found to quench the intrinsic fluorescence of BHb through a static quenching mechanism. The binding constants at 288 K were observed to be (14.023 ± 0.73) × 104 M-1 and (7.848 ± 0.20) × 104 M-1, respectively for quercetin and rutin binding with BHb. Both rutin and quercetin were observed to increase the polarity around the Trp residues of BHb as indicated by synchronous and 3D spectral studies. No significant alterations in the secondary structural components of the protein were caused during the binding of the flavonoids as studied by CD and FTIR studies. The negative molar Gibbs free energies indicated the spontaneity of the interaction processes while the binding processes were characterized by a negative enthalpy change (ΔH) and a positive entropy change (ΔS). The possibility of energy transfer from the donor (BHb) to the acceptor molecules (flavonoids) was indicated by the FRET studies. According to the fluorescence studies, the flavonoids interact near to the β2-Trp37 residue of BHb. Excellent correlations with the experimental studies were observed from the molecular docking and molecular dynamics (MD) simulation studies. Further investigations established that these flavonoids are efficient in the inhibition of glucose mediated glycation of BHb.
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Affiliation(s)
- Sourav Das
- Department of Chemistry, National Institute of Technology, Meghalaya, Shillong 793003, India.
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Patel MP, Siu V, Silva-Garcia A, Xu Q, Li Z, Oksenberg D. Development and validation of an oxygen dissociation assay, a screening platform for discovering, and characterizing hemoglobin-oxygen affinity modifiers. DRUG DESIGN DEVELOPMENT AND THERAPY 2018; 12:1599-1607. [PMID: 29910606 PMCID: PMC5989706 DOI: 10.2147/dddt.s157570] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Introduction Hemoglobin (Hb) is a critical molecule necessary for all vertebrates to maintain aerobic metabolism. Hb–oxygen (O2) affinity modifiers have been studied to address various diseases including sickle cell disease, hypoxemia, tumor hypoxia, and wound healing. However, drug development of exogenous Hb modifiers has been hindered by the lack of a technique to rapidly screen compounds for their ability to alter Hb–O2 affinity. We have developed a novel screening assay based upon the spectral changes observed during Hb deoxygenation and termed it the oxygen dissociation assay (ODA). Methodology ODA allows for the quantitation of oxygenated Hb at given time points during Hb deoxygenation on a 96-well plate. This assay was validated by comparing the ability of 500 Hb modifiers to alter the Hb–O2 affinity in the ODA vs the oxygen equilibrium curves obtained using the industry standard Hemox Analyzer instrument. Results A correlation (R2) of 0.7 indicated that the ODA has the potential to screen and identify potent exogenous Hb modifiers. In addition, it allows for concurrent comparison of compounds, concentrations, buffers, or pHs on the level of Hb oxygenation. Conclusion With a cost-effective, simple, rapid, and highly adaptable assay, the ODA will allow researchers to rapidly characterize Hb–O2 affinity modifiers.
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Affiliation(s)
- Mira P Patel
- Biology Department, Global Blood Therapeutics Inc., South San Francisco, CA, USA
| | - Vincent Siu
- Biology Department, Global Blood Therapeutics Inc., South San Francisco, CA, USA
| | - Abel Silva-Garcia
- Biology Department, Global Blood Therapeutics Inc., South San Francisco, CA, USA
| | - Qing Xu
- Chemistry Department, Global Blood Therapeutics Inc., South San Francisco, CA, USA
| | - Zhe Li
- Chemistry Department, Global Blood Therapeutics Inc., South San Francisco, CA, USA
| | - Donna Oksenberg
- Biology Department, Global Blood Therapeutics Inc., South San Francisco, CA, USA
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43
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Pagare PP, Ghatge MS, Musayev FN, Deshpande TM, Chen Q, Braxton C, Kim S, Venitz J, Zhang Y, Abdulmalik O, Safo MK. Rational design of pyridyl derivatives of vanillin for the treatment of sickle cell disease. Bioorg Med Chem 2018; 26:2530-2538. [PMID: 29655608 DOI: 10.1016/j.bmc.2018.04.015] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2018] [Revised: 03/28/2018] [Accepted: 04/05/2018] [Indexed: 10/17/2022]
Abstract
Hypoxia-induced polymerization of sickle hemoglobin (Hb S) is the principal phenomenon that underlays the pathophysiology and morbidity associated with sickle cell disease (SCD). Opportunely, as an allosteric protein, hemoglobin (Hb) serves as a convenient and potentially critical druggable target. Consequently, molecules that prevent Hb S polymerization (Hb modifiers), and the associated erythrocyte sickling have been investigated-and retain significant interest-as a viable therapeutic strategy for SCD. This group of molecules, including aromatic aldehydes, form high oxygen affinity Schiff-base adducts with Hb S, which are resistant to polymerization. Here, we report the design and synthesis of novel potent antisickling agents (SAJ-009, SAJ-310 and SAJ-270) based on the pharmacophore of vanillin and INN-312, a previously reported pyridyl derivative of vanillin. These novel derivatives exhibited superior in vitro binding and pharmacokinetic properties compared to vanillin, which translated into significantly enhanced allosteric and antisickling properties. Crystal structure studies of liganded Hb in the R2 quaternary state in complex with SAJ-310 provided important insights into the allosteric and antisickling properties of this group of compounds. While these derivatives generally show similar in vitro biological potency, significant structure-dependent differences in their biochemical profiles would help predict the most promising candidates for successful in vivo pre-clinical translational studies and inform further structural modifications to improve on their pharmacologic properties.
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Affiliation(s)
- Piyusha P Pagare
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA
| | - Mohini S Ghatge
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA; The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA
| | - Faik N Musayev
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA; The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA
| | - Tanvi M Deshpande
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA; The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA
| | - Qiukan Chen
- Department of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Courtney Braxton
- The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA
| | - Solyi Kim
- The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA
| | - Jürgen Venitz
- Department of Pharmaceutics, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA
| | - Yan Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA
| | - Osheiza Abdulmalik
- Department of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Martin K Safo
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA; The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, 800 East Leigh Street, Richmond, VA 23298, USA.
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44
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Schay G, Kaposi AD, Smeller L, Szigeti K, Fidy J, Herenyi L. Dissimilar flexibility of α and β subunits of human adult hemoglobin influences the protein dynamics and its alteration induced by allosteric effectors. PLoS One 2018; 13:e0194994. [PMID: 29584765 PMCID: PMC5871000 DOI: 10.1371/journal.pone.0194994] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 03/14/2018] [Indexed: 12/19/2022] Open
Abstract
The general question by what mechanism an "effector" molecule and the hemes of hemoglobin interact over widely separated intramolecular distances to change the oxygen affinity has been extensively investigated, and still has remained of central interest. In the present work we were interested in clarifying the general role of the protein matrix and its dynamics in the regulation of human adult hemoglobin (HbA). We used a spectroscopy approach that yields the compressibility (κ) of the protein matrix around the hemes of the subunits in HbA and studied how the binding of heterotropic allosteric effectors modify this parameter. κ is directly related to the variance of volume fluctuation, therefore it characterizes the molecular dynamics of the protein structure. For the experiments the heme groups either in the α or in the β subunits of HbA were replaced by fluorescent Zn-protoporphyrinIX, and series of fluorescence line narrowed spectra were measured at varied pressures. The evaluation of the spectra yielded the compressibility that showed significant dynamic asymmetry between the subunits: κ of the α subunit was 0.17±0.05/GPa, while for the β subunit it was much higher, 0.36±0.07/GPa. The heterotropic effectors, chloride ions, inositol hexaphosphate and bezafibrate did not cause significant changes in κ of the α subunits, while in the β subunits the effectors lead to a significant reduction down to 0.15±0.04/GPa. We relate our results to structural data, to results of recent functional studies and to those of molecular dynamics simulations, and find good agreements. The observed asymmetry in the flexibility suggests a distinct role of the subunits in the regulation of Hb that results in the observed changes of the oxygen binding capability.
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Affiliation(s)
- Gusztáv Schay
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - András D. Kaposi
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - László Smeller
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - Krisztián Szigeti
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - Judit Fidy
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
| | - Levente Herenyi
- Department of Biophysics and Radiation Biology, Semmelweis University, Budapest, Hungary
- * E-mail:
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45
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Terrell JR, Gumpper RH, Luo M. Hemoglobin crystals immersed in liquid oxygen reveal diffusion channels. Biochem Biophys Res Commun 2018; 495:1858-1863. [DOI: 10.1016/j.bbrc.2017.12.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 12/07/2017] [Indexed: 11/24/2022]
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46
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Sun K, D'Alessandro A, Ahmed MH, Zhang Y, Song A, Ko TP, Nemkov T, Reisz JA, Wu H, Adebiyi M, Peng Z, Gong J, Liu H, Huang A, Wen YE, Wen AQ, Berka V, Bogdanov MV, Abdulmalik O, Han L, Tsai AL, Idowu M, Juneja HS, Kellems RE, Dowhan W, Hansen KC, Safo MK, Xia Y. Structural and Functional Insight of Sphingosine 1-Phosphate-Mediated Pathogenic Metabolic Reprogramming in Sickle Cell Disease. Sci Rep 2017; 7:15281. [PMID: 29127281 PMCID: PMC5681684 DOI: 10.1038/s41598-017-13667-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 09/29/2017] [Indexed: 01/04/2023] Open
Abstract
Elevated sphingosine 1-phosphate (S1P) is detrimental in Sickle Cell Disease (SCD), but the mechanistic basis remains obscure. Here, we report that increased erythrocyte S1P binds to deoxygenated sickle Hb (deoxyHbS), facilitates deoxyHbS anchoring to the membrane, induces release of membrane-bound glycolytic enzymes and in turn switches glucose flux towards glycolysis relative to the pentose phosphate pathway (PPP). Suppressed PPP causes compromised glutathione homeostasis and increased oxidative stress, while enhanced glycolysis induces production of 2,3-bisphosphoglycerate (2,3-BPG) and thus increases deoxyHbS polymerization, sickling, hemolysis and disease progression. Functional studies revealed that S1P and 2,3-BPG work synergistically to decrease both HbA and HbS oxygen binding affinity. The crystal structure at 1.9 Å resolution deciphered that S1P binds to the surface of 2,3-BPG-deoxyHbA and causes additional conformation changes to the T-state Hb. Phosphate moiety of the surface bound S1P engages in a highly positive region close to α1-heme while its aliphatic chain snakes along a shallow cavity making hydrophobic interactions in the “switch region”, as well as with α2-heme like a molecular “sticky tape” with the last 3–4 carbon atoms sticking out into bulk solvent. Altogether, our findings provide functional and structural bases underlying S1P-mediated pathogenic metabolic reprogramming in SCD and novel therapeutic avenues.
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Affiliation(s)
- Kaiqi Sun
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.,Graduate School of Biomedical Science, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Angelo D'Alessandro
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Mostafa H Ahmed
- Department of Medicinal Chemistry, and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Yujin Zhang
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Anren Song
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Tzu-Ping Ko
- Department of Medicinal Chemistry, and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Travis Nemkov
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Julie A Reisz
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Hongyu Wu
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Morayo Adebiyi
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.,Graduate School of Biomedical Science, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Zhangzhe Peng
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.,Department of Nephrology, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China
| | - Jing Gong
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Hong Liu
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.,Graduate School of Biomedical Science, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Aji Huang
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Yuan Edward Wen
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Alexander Q Wen
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Vladimir Berka
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.,Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
| | - Mikhail V Bogdanov
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Osheiza Abdulmalik
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
| | - Leng Han
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Ah-Lim Tsai
- Department of Internal Medicine-Hematology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Modupe Idowu
- Department of Internal Medicine-Hematology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Harinder S Juneja
- Department of Internal Medicine-Hematology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Rodney E Kellems
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA.,Graduate School of Biomedical Science, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - William Dowhan
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA
| | - Kirk C Hansen
- Department of Biochemistry and Molecular Genetics, University of Colorado School of Medicine, Aurora, CO, 80045, USA
| | - Martin K Safo
- Department of Medicinal Chemistry, and The Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, 23298, USA
| | - Yang Xia
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA. .,Graduate School of Biomedical Science, The University of Texas Health Science Center at Houston, Houston, TX, 77030, USA. .,Department of Nephrology, Xiangya Hospital, Central South University, Changsha, Hunan, 410008, China.
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47
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Xu GG, Pagare PP, Ghatge MS, Safo RP, Gazi A, Chen Q, David T, Alabbas AB, Musayev FN, Venitz J, Zhang Y, Safo MK, Abdulmalik O. Design, Synthesis, and Biological Evaluation of Ester and Ether Derivatives of Antisickling Agent 5-HMF for the Treatment of Sickle Cell Disease. Mol Pharm 2017; 14:3499-3511. [PMID: 28858508 PMCID: PMC5871537 DOI: 10.1021/acs.molpharmaceut.7b00553] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Candidate drugs to counter intracellular polymerization of deoxygenated sickle hemoglobin (Hb S) continue to represent a promising approach to mitigating the primary cause of the pathophysiology associated with sickle cell disease (SCD). One such compound is the naturally occurring antisickling agent, 5-hydroxymethyl-2-furfural (5-HMF), which has been studied in the clinic for the treatment of SCD. As part of our efforts to develop novel efficacious drugs with improved pharmacologic properties, we structurally modified 5-HMF into 12 ether and ester derivatives. The choice of 5-HMF as a pharmacophore was influenced by a combination of its demonstrated attractive hemoglobin modifying and antisickling properties, well-known safety profiles, and its reported nontoxic major metabolites. The derivatives were investigated for their time- and/or dose-dependent effects on important antisickling parameters, such as modification of hemoglobin, corresponding changes in oxygen affinity, and inhibition of red blood cell sickling. The novel test compounds bound and modified Hb and concomitantly increased the protein affinity for oxygen. Five of the derivatives exhibited 1.5- to 4.0-fold higher antisickling effects than 5-HMF. The binding mode of the compounds with Hb was confirmed by X-ray crystallography and, in part, helps explain their observed biochemical properties. Our findings, in addition to the potential therapeutic application, provide valuable insights and potential guidance for further modifications of these (and similar) compounds to enhance their pharmacologic properties.
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Affiliation(s)
- Guoyan G. Xu
- Department of Medicinal Chemistry, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Piyusha P. Pagare
- Department of Medicinal Chemistry, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Mohini S. Ghatge
- Department of Medicinal Chemistry, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
- The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Ronni P. Safo
- The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Aheema Gazi
- Department of Biology, School of Arts & Sciences, University of Richmond, Richmond, Virginia 23173, United States
| | - Qiukan Chen
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, United States
| | - Tanya David
- The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Alhumaidi B. Alabbas
- Department of Medicinal Chemistry, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
- The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Faik N. Musayev
- Department of Medicinal Chemistry, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
- The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Jürgen Venitz
- Department of Pharmaceutics, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Yan Zhang
- Department of Medicinal Chemistry, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Martin K. Safo
- Department of Medicinal Chemistry, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
- The Institute for Structural Biology, Drug Discovery, and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, Virginia 23298, United States
| | - Osheiza Abdulmalik
- Division of Hematology, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, United States
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48
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Tobi D. Dynamical differences of hemoglobin and the ionotropic glutamate receptor in different states revealed by a new dynamics alignment method. Proteins 2017; 85:1507-1517. [PMID: 28459140 DOI: 10.1002/prot.25311] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 04/02/2017] [Accepted: 04/24/2017] [Indexed: 12/26/2022]
Abstract
A new algorithm for comparison of protein dynamics is presented. Compared protein structures are superposed and their modes of motions are calculated using the anisotropic network model. The obtained modes are aligned using the dynamic programming algorithm of Needleman and Wunsch, commonly used for sequence alignment. Dynamical comparison of hemoglobin in the T and R2 states reveals that the dynamics of the allosteric effector 2,3-bisphosphoglycerate binding site is different in the two states. These differences can contribute to the selectivity of the effector to the T state. Similar comparison of the ionotropic glutamate receptor in the kainate+(R,R)-2b and ZK bound states reveals that the kainate+(R,R)-2b bound states slow modes describe upward motions of ligand binding domain and the transmembrane domain regions. Such motions may lead to the opening of the receptor. The upper lobes of the LBDs of the ZK bound state have a smaller interface with the amino terminal domains above them and have a better ability to move together. The present study exemplifies the use of dynamics comparison as a tool to study protein function. Proteins 2017; 85:1507-1517. © 2014 Wiley Periodicals, Inc.
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Affiliation(s)
- Dror Tobi
- Department of Computer Sciences, Ariel University, Ariel, 40700, Israel.,Department of Molecular Biology, Ariel University, Ariel, 40700, Israel
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49
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Oder E, Safo MK, Abdulmalik O, Kato GJ. New developments in anti-sickling agents: can drugs directly prevent the polymerization of sickle haemoglobin in vivo? Br J Haematol 2016; 175:24-30. [PMID: 27605087 DOI: 10.1111/bjh.14264] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 05/29/2016] [Indexed: 11/27/2022]
Abstract
The hallmark of sickle cell disease is the polymerization of sickle haemoglobin due to a point mutation in the β-globin gene (HBB). Under low oxygen saturation, sickle haemoglobin assumes the tense (T-state) deoxygenated conformation that can form polymers, leading to rigid erythrocytes with impaired blood vessel transit, compounded or initiated by adhesion of erythrocytes to endothelium, neutrophils and platelets. This process results in vessel occlusion and ischaemia, with consequent acute pain, chronic organ damage, morbidity and mortality. Pharmacological agents that stabilize the higher oxygen affinity relaxed state (R-state) and/or destabilize the lower oxygen affinity T-state of haemoglobin have the potential to delay the sickling of circulating red cells by slowing polymerization kinetics. Relevant classes of agents include aromatic aldehydes, thiol derivatives, isothiocyanates and acyl salicylates derivatives. The aromatic aldehyde, 5-hydroxymethylfurfural (5-HMF) increases oxygen affinity of sickle haemoglobin and reduces hypoxia-induced sickling in vitro and protects sickle cell mice from effects of hypoxia. It has completed pre-clinical testing and has entered clinical trials as treatment for sickle cell disease. A related molecule, GBT440, has shown R-state stabilization and increased oxygen affinity in preclinical testing. Allosteric modifiers of haemoglobin as direct anti-sickling agents target the fundamental pathophysiological mechanism of sickle cell disease.
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Affiliation(s)
- Esther Oder
- School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA
| | - Martin K Safo
- Department of Medicinal Chemistry, Institute for Structural Biology, Drug Discovery and Development, School of Pharmacy, Virginia Commonwealth University, Richmond, VA, USA
| | - Osheiza Abdulmalik
- Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Gregory J Kato
- Department of Medicine, Division of Hematology-Oncology and the Heart, Lung, Blood and Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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50
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Aryloxyalkanoic Acids as Non-Covalent Modifiers of the Allosteric Properties of Hemoglobin. Molecules 2016; 21:molecules21081057. [PMID: 27529207 PMCID: PMC5453642 DOI: 10.3390/molecules21081057] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 07/29/2016] [Accepted: 08/09/2016] [Indexed: 11/16/2022] Open
Abstract
Hemoglobin (Hb) modifiers that stereospecifically inhibit sickle hemoglobin polymer formation and/or allosterically increase Hb affinity for oxygen have been shown to prevent the primary pathophysiology of sickle cell disease (SCD), specifically, Hb polymerization and red blood cell sickling. Several such compounds are currently being clinically studied for the treatment of SCD. Based on the previously reported non-covalent Hb binding characteristics of substituted aryloxyalkanoic acids that exhibited antisickling properties, we designed, synthesized and evaluated 18 new compounds (KAUS II series) for enhanced antisickling activities. Surprisingly, select test compounds showed no antisickling effects or promoted erythrocyte sickling. Additionally, the compounds showed no significant effect on Hb oxygen affinity (or in some cases, even decreased the affinity for oxygen). The X-ray structure of deoxygenated Hb in complex with a prototype compound, KAUS-23, revealed that the effector bound in the central water cavity of the protein, providing atomic level explanations for the observed functional and biological activities. Although the structural modification did not lead to the anticipated biological effects, the findings provide important direction for designing candidate antisickling agents, as well as a framework for novel Hb allosteric effectors that conversely, decrease the protein affinity for oxygen for potential therapeutic use for hypoxic- and/or ischemic-related diseases.
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