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Antony P, Baby B, Jobe A, Vijayan R. Computational Modeling of the Interactions between DPP IV and Hemorphins. Int J Mol Sci 2024; 25:3059. [PMID: 38474306 DOI: 10.3390/ijms25053059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/20/2024] [Accepted: 02/20/2024] [Indexed: 03/14/2024] Open
Abstract
Type 2 diabetes is a chronic metabolic disorder characterized by high blood glucose levels due to either insufficient insulin production or ineffective utilization of insulin by the body. The enzyme dipeptidyl peptidase IV (DPP IV) plays a crucial role in degrading incretins that stimulate insulin secretion. Therefore, the inhibition of DPP IV is an established approach for the treatment of diabetes. Hemorphins are a class of short endogenous bioactive peptides produced by the enzymatic degradation of hemoglobin chains. Numerous in vitro and in vivo physiological effects of hemorphins, including DPP IV inhibiting activity, have been documented in different systems and tissues. However, the underlying molecular binding behavior of these peptides with DPP IV remains unknown. Here, computational approaches such as protein-peptide molecular docking and extensive molecular dynamics (MD) simulations were employed to identify the binding pose and stability of peptides in the active site of DPP IV. Findings indicate that hemorphins lacking the hydrophobic residues LVV and VV at the N terminal region strongly bind to the conserved residues in the active site of DPP IV. Furthermore, interactions with these critical residues were sustained throughout the duration of multiple 500 ns MD simulations. Notably, hemorphin 7 showed higher binding affinity and sustained interactions by binding to S1 and S2 pockets of DPP IV.
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Affiliation(s)
- Priya Antony
- Department of Biology, College of Science, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
| | - Bincy Baby
- Department of Biology, College of Science, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
| | - Amie Jobe
- Department of Biology, College of Science, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
| | - Ranjit Vijayan
- Department of Biology, College of Science, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
- The Big Data Analytics Center, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
- Zayed Center for Health Sciences, United Arab Emirates University, Al Ain P.O. Box 15551, United Arab Emirates
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2
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Todorov P, Georgieva S, Peneva P, Nikolov S, Rangelov M, Todorova N, Pechlivanova D, Tchekalarova J. Synthesis, molecular docking, electrochemical and fluorimetric analysis of new caffeic and cinnamic acid-conjugated hemorphin derivatives designed as potential anticonvulsant and antinociceptive agents. Bioorg Chem 2024; 143:107063. [PMID: 38150935 DOI: 10.1016/j.bioorg.2023.107063] [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: 10/25/2023] [Revised: 11/17/2023] [Accepted: 12/23/2023] [Indexed: 12/29/2023]
Abstract
Based on the pharmacophore model of opioid receptors, our team recently synthesized a series of short-chain hemorphin peptide analogs containing non-natural amino acids. They demonstrated anticonvulsant and antinociceptive activity with low neurotoxicity. In the present study, a series of novel bioconjugates of N-modified hemorphin analogs containing second pharmacophore cinnamic acids (CA) or caffeic (KA) were synthesized by a traditional solid-phase Fmoc chemistry method for peptide synthesis. Electrochemical and fluorimetric analysis, in vivo anticonvulsant and antinociceptive activity in mice were conducted on the compounds. The three CA acid- (H4-CA, H5-CA, and H7-CA) and three KA acid- (H4-KA, H5-KA, and H7-KA) conjugated hemorphin derivatives exhibited potency at the highest doses of 2 µg/5 µl, administered by intracerebroventricular (icv) mode, against seizure spread in the maximal electroshock test (MES) in mice. The KA-conjugated H5-KA derivate, at the lowest dose, was the only compound that suppressed clonic seizures in the subcutaneous pentylenetetrazol (scPTZ) test. Except for the H5-CA, all tested CA acid- and KA acid-conjugated peptide derivates had the potency to increase the latency for clonic seizures in a dose-dependent mode. The activity against the psychomotor seizures in the 6-Hz test was detected only for the H4-CA (0.5 µg) and H4-KA (0.5 µg and 1 µg), respectively. All investigated peptides showed a more pronounced antinociceptive effect in the "intraplantar formalin" test compared to the "hot plate" test. Shorter chain analogs showed a better antinociceptive profile against tonic pain. The data suggest a DOR and KOR-mediated mechanism of action. According to the docking analysis, H7-CA showed a different antinociceptive profile than other investigated peptides. The novel peptide derivates did not exhibit neurotoxicity in the rotarod test. Our findings suggest that conjugated CA and KA morphine peptides can be used to develop novel morphine-related analogs with anticonvulsant and antinociceptive activity.
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Affiliation(s)
- Petar Todorov
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria.
| | - Stela Georgieva
- Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria
| | - Petia Peneva
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria
| | - Spas Nikolov
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria; Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria
| | - Miroslav Rangelov
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Nadezhda Todorova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Daniela Pechlivanova
- Faculty of Medicine, Sofia University "St. Kliment Ohridski", 1407 Sofia, Bulgaria; Institute of Neurobiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Jana Tchekalarova
- Institute of Neurobiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
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Todorov P, Assenov B, Angelov D, Dzhambazova E, Pechlivanova D. Behavioral Effects and Analgesic Profile of Hemoglobin-Derived Valorphin and Its Synthetic Analog in Rodents. Biomedicines 2023; 11:2783. [PMID: 37893157 PMCID: PMC10603931 DOI: 10.3390/biomedicines11102783] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 10/09/2023] [Accepted: 10/12/2023] [Indexed: 10/29/2023] Open
Abstract
Valorphin (V1) is a naturally occurring peptide derived from hemoglobin that has been found to have an affinity for opioid receptors and exhibits antinociceptive and anticonvulsant activity. Some of its synthetic analogs containing an aminophosphonate moiety show structure-dependent potent antinociceptive effects. This study aimed to reveal a detailed picture of the antinociceptive mechanisms and behavioral effects of V1 and its recently synthesized phosphopeptide analog V2p in rodents using a range of methods. The studied peptides significantly reduced acute (mean V1-9.0, V2p-5.8 vs. controls-54.1 s) and inflammatory (mean V1-57.9 and V2p-53.3 vs. controls-107.6 s) nociceptive pain in the formalin test, as well as carrageenan-induced hyperalgesia (mean V1-184.7 and V2p-107.3 vs. controls-61.8 g) in the paw pressure test. These effects are mediated by activation of opioid receptors with a predominance of kappa in V1 antinociception and by delta, kappa, and mu receptors in V2p-induced antinociception. Both peptides did not change the levels of TNF-alpha and IL-1-beta in blood serum. V1 induces depression-like behavior, and V2p shows a tendency toward anxiolysis and short-term impairment of motor coordination without affecting exploratory behavior. The results characterize valorphin and its derivative as promising analgesics that exert their effects both centrally and peripherally, without causing severe behavioral changes in experimental animals. These encouraging data are a foundation for future studies focusing on the effects of hemorphins after long-term treatment.
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Affiliation(s)
- Petar Todorov
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
| | - Borislav Assenov
- Institute of Neurobiology, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 23, 1113 Sofia, Bulgaria; (B.A.); (D.A.)
- Faculty of Medicine, Sofia University “St. Kliment Ohridski”, 1 Kozyak Str., 1407 Sofia, Bulgaria;
| | - Dimo Angelov
- Institute of Neurobiology, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 23, 1113 Sofia, Bulgaria; (B.A.); (D.A.)
| | - Elena Dzhambazova
- Faculty of Medicine, Sofia University “St. Kliment Ohridski”, 1 Kozyak Str., 1407 Sofia, Bulgaria;
| | - Daniela Pechlivanova
- Institute of Neurobiology, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 23, 1113 Sofia, Bulgaria; (B.A.); (D.A.)
- Faculty of Medicine, Sofia University “St. Kliment Ohridski”, 1 Kozyak Str., 1407 Sofia, Bulgaria;
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4
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Hellinger R, Sigurdsson A, Wu W, Romanova EV, Li L, Sweedler JV, Süssmuth RD, Gruber CW. Peptidomics. NATURE REVIEWS. METHODS PRIMERS 2023; 3:25. [PMID: 37250919 PMCID: PMC7614574 DOI: 10.1038/s43586-023-00205-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/09/2023] [Indexed: 05/31/2023]
Abstract
Peptides are biopolymers, typically consisting of 2-50 amino acids. They are biologically produced by the cellular ribosomal machinery or by non-ribosomal enzymes and, sometimes, other dedicated ligases. Peptides are arranged as linear chains or cycles, and include post-translational modifications, unusual amino acids and stabilizing motifs. Their structure and molecular size render them a unique chemical space, between small molecules and larger proteins. Peptides have important physiological functions as intrinsic signalling molecules, such as neuropeptides and peptide hormones, for cellular or interspecies communication, as toxins to catch prey or as defence molecules to fend off enemies and microorganisms. Clinically, they are gaining popularity as biomarkers or innovative therapeutics; to date there are more than 60 peptide drugs approved and more than 150 in clinical development. The emerging field of peptidomics comprises the comprehensive qualitative and quantitative analysis of the suite of peptides in a biological sample (endogenously produced, or exogenously administered as drugs). Peptidomics employs techniques of genomics, modern proteomics, state-of-the-art analytical chemistry and innovative computational biology, with a specialized set of tools. The complex biological matrices and often low abundance of analytes typically examined in peptidomics experiments require optimized sample preparation and isolation, including in silico analysis. This Primer covers the combination of techniques and workflows needed for peptide discovery and characterization and provides an overview of various biological and clinical applications of peptidomics.
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Affiliation(s)
- Roland Hellinger
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
| | - Arnar Sigurdsson
- Institut für Chemie, Technische Universität Berlin, Berlin, Germany
| | - Wenxin Wu
- School of Pharmacy and Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Elena V Romanova
- Department of Chemistry, University of Illinois, Urbana, IL, USA
| | - Lingjun Li
- School of Pharmacy and Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | | | | | - Christian W Gruber
- Center for Physiology and Pharmacology, Medical University of Vienna, Vienna, Austria
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5
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Jobe A, Antony P, Altabbal S, Al Dhaheri Y, Vijayan R. Interaction of hemorphins with ACE homologs. Sci Rep 2023; 13:3743. [PMID: 36878973 PMCID: PMC9987361 DOI: 10.1038/s41598-023-30771-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 02/28/2023] [Indexed: 03/08/2023] Open
Abstract
Hemorphins, short bioactive peptides produced by enzymatic cleavage of β-hemoglobin, exhibit antihypertensive properties by inhibiting angiotensin-1 converting enzyme (ACE1). ACE1 is a key player in the renin-angiotensin system (RAS) and regulates blood pressure. ACE1 and its homolog, ACE2, which exhibit opposing activities in the RAS, share considerable similarity in their catalytic domains. The primary objective of this study was to identify and contrast the molecular mechanisms underlying the interaction of hemorphins of camels and that of other mammals with the two ACE homologs. In silico docking and molecular dynamics simulations were performed for ACE1 and ACE2, along with in vitro confirmatory assays for ACE1. The C-domain of ACE1, primarily involved in regulating blood pressure, was used along with the N-terminal peptidase domain of ACE2. The findings revealed conserved hemorphin interactions with equivalent regions of the two ACE homologs and differential residue-level interactions reflecting the substrate preferences of ACE1 and ACE2 considering their opposing functions. Therefore, conserved residue-level associations and implications of poorly conserved regions between the two ACE receptors may potentially guide the discovery of selective domain-specific inhibitors. The findings of this study can provide a basis for the treatment of related disorders in the future.
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Affiliation(s)
- Amie Jobe
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | - Priya Antony
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | - Suhib Altabbal
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | - Yusra Al Dhaheri
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | - Ranjit Vijayan
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates. .,The Big Data Analytics Center, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates. .,Zayed Center for Health Sciences, United Arab Emirates University, PO Box 17666, Al Ain, United Arab Emirates.
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6
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Georgieva S, Todorov P, Staneva D, Grozdanov P, Nikolova I, Grabchev I. Metal-Peptide Complexes with Antimicrobial Potential for Cotton Fiber Protection. J Funct Biomater 2023; 14:jfb14020106. [PMID: 36826905 PMCID: PMC9962186 DOI: 10.3390/jfb14020106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 02/05/2023] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
A study of the formation of copper (II) complexes with hemorphin peptide motifs in alkalic water solutions is presented. The effect of the peptide ligand on the complexing properties of the Cu (II) ion was quantified by giving the stoichiometry and stability of the complex compounds in the medium in which they are formed using voltammetric (cyclic) and spectral (UV-Vis and fluorimetric) analytical techniques. The resulting complexes were examined via IR spectroscopy to detect M-N and M-O oscillations and using the EPR approach in solution and in the solid phase to view the coordination and ligand binding regime. The possibility of the synergistic action of copper ions in the antivirus protection processes of cotton fibers coated in the same solvent with the newly obtained complex compounds was also investigated. One of the advantages is the formation of the complexes in an environment where the immobilization takes place, which contributes to increasing the efficiency of the process. The obtained results may serve as an aid for future more detailed biological studies of structure-activity relationships (SARs).
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Affiliation(s)
- Stela Georgieva
- Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria
- Correspondence: (S.G.); (P.T.)
| | - Petar Todorov
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria
- Correspondence: (S.G.); (P.T.)
| | - Desislava Staneva
- Department of Textile, Leathers and Fuels, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria
| | - Petar Grozdanov
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Ivanka Nikolova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
| | - Ivo Grabchev
- Faculty of Medicine, Sofia University “St. Kl. Ohridski”, 1407 Sofia, Bulgaria
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Mendonça MM, da Cruz KR, dos Santos Silva FC, Fontes MAP, Xavier CH. Are hemoglobin-derived peptides involved in the neuropsychiatric symptoms caused by SARS-CoV-2 infection? REVISTA BRASILEIRA DE PSIQUIATRIA (SAO PAULO, BRAZIL : 1999) 2022; 44. [PMID: 35896170 PMCID: PMC9375661 DOI: 10.47626/1516-4446-2021-2339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 02/16/2022] [Indexed: 11/29/2022]
Abstract
Follow-up of patients affected by COVID-19 has unveiled remarkable findings. Among the several sequelae caused by SARS-CoV-2 viral infection, it is particularly noteworthy that patients are prone to developing depression, anxiety, cognitive disorders, and dementia as part of the post-COVID-19 syndrome. The multisystem aspects of this disease suggest that multiple mechanisms may converge towards post-infection clinical manifestations. The literature provides mechanistic hypotheses related to changes in classical neurotransmission evoked by SARS-CoV-2 infection; nonetheless, the interaction of peripherally originated classical and non-canonic peptidergic systems may play a putative role in this neuropathology. A wealth of robust findings shows that hemoglobin-derived peptides are able to control cognition, memory, anxiety, and depression through different mechanisms. Early erythrocytic death is found during COVID-19, which would cause excess production of hemoglobin-derived peptides. Following from this premise, the present review sheds light on a possible involvement of hemoglobin-derived molecules in the COVID-19 pathophysiology by fostering neuroscientific evidence that supports the contribution of this non-canonic peptidergic pathway. This rationale may broaden knowledge beyond the currently available data, motivating further studies in the field and paving ways for novel laboratory tests and clinical approaches.
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Affiliation(s)
- Michelle Mendanha Mendonça
- Laboratório de Neurobiologia de Sistemas, Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Kellen Rosa da Cruz
- Laboratório de Neurobiologia de Sistemas, Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brazil
| | - Fernanda Cacilda dos Santos Silva
- Laboratório de Fisiologia Cardiovascular, Departamento de Ciências Biológicas, Instituto de Ciências Biológicas, Universidade Federal de Ouro Preto, Ouro Preto, MG, Brazil
| | - Marco Antônio Peliky Fontes
- Laboratório de Hipertensão, Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Carlos Henrique Xavier
- Laboratório de Neurobiologia de Sistemas, Departamento de Ciências Fisiológicas, Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, GO, Brazil
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8
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Todorov P, Georgieva S, Staneva D, Peneva P, Grozdanov P, Nikolova I, Vasileva-Tonkova E, Grabchev I. Study of Novel Peptides for Antimicrobial Protection in Solution and on Cotton Fabric. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27154770. [PMID: 35897948 PMCID: PMC9332204 DOI: 10.3390/molecules27154770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Revised: 07/14/2022] [Accepted: 07/22/2022] [Indexed: 11/16/2022]
Abstract
Some new N- and C-modified biomolecular peptide analogues of both VV-hemorphin-5 and VV-hemorphin-7 with varied amino acids (Cys, Glu, His), 1-adamantanecarboxylic acid, and niacin (nicotinic acid) were synthesized by solid-phase peptide synthesis-Fmoc (9-fluorenylmethoxy-carbonyl) chemistry and were characterized in water solutions with different pH using spectroscopic and electrochemical techniques. Basic physicochemical properties related to the elucidation of the peptide structure at physiological pH have been also studied. The results showed that the interaction of peptide compounds with light and electricity preserves the structural and conformational integrity of the compounds in the solutions. Moreover, textile cotton fibers were modified with the new compounds and the binding of the peptides to the surface of the material was proved by FTIR and SEM analysis. Washing the material with an alkaline soap solution did not show a violation of the modified structure of the cotton. Antiviral activity against the human respiratory syncytial virus (HRSV-S2) and human adenovirus serotype 5 (HAdV-5), the antimicrobial activity against B. cereus and P. aeruginosa used as model bacterial strains and cytotoxic effect of the peptide derivatives and modified cotton textile material has been evaluated. Antimicrobial tests showed promising activity of the newly synthesized compounds against the used Gram-positive and Gram-negative bacteria. The compounds C-V, H-V, AC-V, and AH-V were found slightly more active than NH7C and NCH7. The activity has been retained after the deposition of the compounds on cotton fibers.
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Affiliation(s)
- Petar Todorov
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
- Correspondence: ; Tel.: +359-2-8163423
| | - Stela Georgieva
- Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
| | - Desislava Staneva
- Department of Textile and Leathers, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
| | - Petia Peneva
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
| | - Petar Grozdanov
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (P.G.); (I.N.); (E.V.-T.)
| | - Ivanka Nikolova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (P.G.); (I.N.); (E.V.-T.)
| | - Evgenia Vasileva-Tonkova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (P.G.); (I.N.); (E.V.-T.)
| | - Ivo Grabchev
- Faculty of Medicine, Sofia University “St. Kl. Ohridski”, 1407 Sofia, Bulgaria;
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9
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Investigation of the structure–activity relationship in a series of new LVV- and VV-hemorphin-7 analogues designed as potential anticonvulsant agents. Amino Acids 2022; 54:261-275. [DOI: 10.1007/s00726-021-03112-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2021] [Accepted: 11/24/2021] [Indexed: 11/27/2022]
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10
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Todorov P, Georgieva S, Staneva D, Peneva P, Grozdanov P, Nikolova I, Grabchev I. Synthesis of New Modified with Rhodamine B Peptides for Antiviral Protection of Textile Materials. Molecules 2021; 26:molecules26216608. [PMID: 34771015 PMCID: PMC8587962 DOI: 10.3390/molecules26216608] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 10/27/2021] [Accepted: 10/29/2021] [Indexed: 01/11/2023] Open
Abstract
Here we report on the synthesis and characterization of three new N-modified analogues of hemorphin-4 with rhodamine B. Modified with chloroacetyl, chloride cotton fabric has been dyed and color coordinates of the obtained textile materials were determined. Antiviral and virucidal activities of both the peptide-rhodamine B compounds and the dyed textile material were studied. Basic physicochemical properties (acid-base behavior, solvent influence, kinetics) related to the elucidation of structural activity of the new modified peptides based on their steric open/closed ring effect were studied. The obtained results lead to the conclusion that in protic solvent with change in pH of the environment, direct control over the dyeing of textiles can be achieved. Both the new hybrid peptide compounds and the modification of functionalized textile materials with these bioactive hemorphins showed virucidal activity against the human respiratory syncytial virus (HRSV-S2) and human adenovirus serotype 5 (HAdV-5) for different time intervals (30 and 60 min) and the most active compound was Rh-3.
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Affiliation(s)
- Petar Todorov
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
- Correspondence: ; Tel.: +359-2-8163423
| | - Stela Georgieva
- Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
| | - Desislava Staneva
- Department of Textile and Leathers, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
| | - Petia Peneva
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756 Sofia, Bulgaria;
| | - Petar Grozdanov
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (P.G.); (I.N.)
| | - Ivanka Nikolova
- The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria; (P.G.); (I.N.)
| | - Ivo Grabchev
- Faculty of Medicine, Sofia University “St. Kl. Ohridski”, 1407 Sofia, Bulgaria;
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11
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Hemorphins-From Discovery to Functions and Pharmacology. Molecules 2021; 26:molecules26133879. [PMID: 34201982 PMCID: PMC8270332 DOI: 10.3390/molecules26133879] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/18/2021] [Accepted: 06/21/2021] [Indexed: 01/31/2023] Open
Abstract
During the last three decades, a variety of different studies on bioactive peptides that are opioid receptor ligands, have been carried out, with regard to their isolation and identification, as well as their molecular functions in living organisms. Thus, in this review, we would like to summarize the present state-of-the art concerning hemorphins, methodological aspects of their identification, and their potential role as therapeutic agents. We have collected and discussed articles describing hemorphins, from their discovery up until now, thus presenting a very wide spectrum of their characteristic and applications. One of the major assets of the present paper is a combination of analytical and pharmacological aspects of peptides described by a team who participated in the initial research on hemorphins. This review is, in part, focused on the analysis of endogenous opioid peptides in biological samples using advanced techniques, description of the identification of synthetic/endogenous hemorphins, their involvement in pharmacology, learning, pain and other function. Finally, the part regarding hemorphin analogues and their synthesis, has been added.
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12
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Hemorphins Targeting G Protein-Coupled Receptors. Pharmaceuticals (Basel) 2021; 14:ph14030225. [PMID: 33799973 PMCID: PMC7998264 DOI: 10.3390/ph14030225] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 02/28/2021] [Accepted: 03/03/2021] [Indexed: 12/22/2022] Open
Abstract
Hemorphins are short peptides produced by the proteolysis of the beta subunit of hemoglobin. These peptides have diverse physiological effects especially in the nervous and the renin-angiotensin systems. Such effects occur through the modulation of a diverse range of proteins including enzymes and receptors. In this review, we focus on pharmacological and functional targeting of G protein-coupled receptors (GPCRs) by hemorphins and their implication in physiology and pathophysiology. Among GPCRs, the opioid receptors constitute the first set of targets of hemorphins with implication in analgesia. Subsequently, several other GPCRs have been reported to be directly or indirectly involved in hemorphins’ action. This includes the receptors for angiotensin II, oxytocin, bombesin, and bradykinin, as well as the human MAS-related G protein-coupled receptor X1. Interestingly, both orthosteric activation and allosteric modulation of GPCRs by hemorphins have been reported. This review links hemorphins with GPCR pharmacology and signaling, supporting the implication of GPCRs in hemorphins’ effects. Thus, this aids a better understanding of the molecular basis of the action of hemorphins and further demonstrates that hemorphin-GPCR axis constitutes a valid target for therapeutic intervention in different systems.
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Mapping drug-target interactions and synergy in multi-molecular therapeutics for pressure-overload cardiac hypertrophy. NPJ Syst Biol Appl 2021; 7:11. [PMID: 33589646 PMCID: PMC7884732 DOI: 10.1038/s41540-021-00171-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 01/13/2021] [Indexed: 01/31/2023] Open
Abstract
Advancements in systems biology have resulted in the development of network pharmacology, leading to a paradigm shift from "one-target, one-drug" to "target-network, multi-component therapeutics". We employ a chimeric approach involving in-vivo assays, gene expression analysis, cheminformatics, and network biology to deduce the regulatory actions of a multi-constituent Ayurvedic concoction, Amalaki Rasayana (AR) in animal models for its effect in pressure-overload cardiac hypertrophy. The proteomics analysis of in-vivo assays for Aorta Constricted and Biologically Aged rat models identify proteins expressed under each condition. Network analysis mapping protein-protein interactions and synergistic actions of AR using multi-component networks reveal drug targets such as ACADM, COX4I1, COX6B1, HBB, MYH14, and SLC25A4, as potential pharmacological co-targets for cardiac hypertrophy. Further, five out of eighteen AR constituents potentially target these proteins. We propose a distinct prospective strategy for the discovery of network pharmacological therapies and repositioning of existing drug molecules for treating pressure-overload cardiac hypertrophy.
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14
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Insights into the Interaction of LVV-Hemorphin-7 with Angiotensin II Type 1 Receptor. Int J Mol Sci 2020; 22:ijms22010209. [PMID: 33379211 PMCID: PMC7795518 DOI: 10.3390/ijms22010209] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 12/17/2020] [Accepted: 12/24/2020] [Indexed: 12/17/2022] Open
Abstract
Hemorphins are known for their role in the control of blood pressure. Recently, we revealed the positive modulation of the angiotensin II (AngII) type 1 receptor (AT1R) by LVV-hemorphin-7 (LVV-H7) in human embryonic kidney (HEK293) cells. Here, we examined the molecular binding behavior of LVV-H7 on AT1R and its effect on AngII binding using a nanoluciferase-based bioluminescence resonance energy transfer (NanoBRET) assay in HEK293FT cells, as well as molecular docking and molecular dynamics (MD) studies. Saturation and real-time kinetics supported the positive effect of LVV-H7 on the binding of AngII. While the competitive antagonist olmesartan competed with AngII binding, LVV-H7 slightly, but significantly, decreased AngII’s kD by 2.6 fold with no effect on its Bmax. Molecular docking and MD simulations indicated that the binding of LVV-H7 in the intracellular region of AT1R allosterically potentiates AngII binding. LVV-H7 targets residues on intracellular loops 2 and 3 of AT1R, which are known binding sites of allosteric modulators in other GPCRs. Our data demonstrate the allosteric effect of LVV-H7 on AngII binding, which is consistent with the positive modulation of AT1R activity and signaling previously reported. This further supports the pharmacological targeting of AT1R by hemorphins, with implications in vascular and renal physiology.
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15
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Sahin K. In silico identification of angiotensin-1 converting enzyme inhibitors using text mining and virtual screening. J Biomol Struct Dyn 2020; 40:1152-1162. [PMID: 33016840 DOI: 10.1080/07391102.2020.1827038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Cardiovascular diseases are the world's leading cause of death. Hypertension is an important risk factor for cardiovascular and renal diseases. Angiotensin-converting enzyme (ACE) can be a possible therapeutic target for managing angiotensin I conversion to angiotensin II and ultimately controlling hypertension. Indole is an significant fragment used in many medicines approved by FDA. For this reason, the molecules in their fragments containing" indol" keywords were taken from the Specs-SC (small compound) database. The predicted therapeutc activity values (TAV) of these compounds against hypertension were evaluated using binary models of QSAR by MetaCore/MetaDrug. For the 26 separate QSAR models of toxicity, molecules with measured TAV greater than 0.5 were used. 3792 non-toxic compounds were investigated by molecular docking study and molecular dynamics simulations for their ACE inhibitory activity. Glide standard precision (SP) of Maestro Molecular Modeling pocket was used to perform molecular docking. Short molecular dynamics (MD) simulations (5-ns) were carried out by initiating the top docking poses of selected 40 molecules. To quantitatively evaluate the predicted binding affinity of a screened compound, average MM/GBSA scores of screened ligands were calculated and based on their binding free energy values, hit compounds were identified for the long (100-ns) MD simulations. Root mean square deviation and root mean square fluctuations were also calculated to assess the structural characteristics and observe fluctuations of the 100-ns time scale. Thus, with the application of text mining and integrated molecular modeling we reported novel indole-based hit inhibitors for ACE-1.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Kader Sahin
- Computational Biology and Molecular Simulations Laboratory, Department of Biophysics, School of Medicine, Bahcesehir University, Istanbul, Turkey
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16
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Todorov P, Peneva P, Tchekalarova J, Georgieva S, Rangelov M, Todorova N. Structure-activity relationship study on new hemorphin-4 analogues containing steric restricted amino acids moiety for evaluation of their anticonvulsant activity. Amino Acids 2020; 52:1375-1390. [PMID: 33011823 DOI: 10.1007/s00726-020-02898-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 09/28/2020] [Indexed: 12/31/2022]
Abstract
In the present study, several new analogues of hemorphin-4, modified with unnatural conformationally restricted amino acids followed the structure Aaa-Tyr-Xxx-Trp-Thr-NH2, where Aaa is the low-molecular-weight lipophilic adamantyl building block, and Xxx is Ac5c (1-aminocyclopentanecarboxylic acid) or Ac6c (1-aminocyclohexane carboxylic acid) was synthesized, characterized and investigated for anticonvulsant activity in three seizure tests, the maximal electroshock test (MES), 6-Hz psychomotor seizure test and timed intravenous pentylenetetrazole infusion (ivPTZ) test. The acute neurological toxicity was determined using the rota-rod test. The new synthetic neuropeptide analogues were prepared by solid-phase peptide synthesis-Fmoc chemistry and were evaluated in three doses of 1, 3 and 5 µg, respectively, administered intracerebroventricularly in male ICR mice. The physicochemical properties of these peptide analogues were evaluated as pKa and pI values were calculated using potentiometry. The IR spectrum of the compounds was recorded and the characteristic lines of both adamantane moiety and the peptide backbone were registered in the wavelength range from 4000 to 400 cm-1. The hexapeptide Ang IV was used as a positive control. From the six synthesized peptide analogues, the P4-5 was the most active at doses of 1 and 3 µg in the three seizure tests. The order of potency of other peptides was as follows: P4 > P4-3 = P4-4 > P4-2 > Ang IV in MES, P4-4 ≥ P4-1 > P4-3 > P4-2 > P4 > Ang IV in 6-Hz test and P4-4 = P4-3 > P4-2 = P4 > Ang IV in ivPTZ test. None of the peptides displayed neurotoxicity in the rota-rod test. Docking study results suggest that direct H-bonding and ionic interactions between our synthetic ligands and residues, responsible for coordination of Zn2+ along with hydrophobic interactions between our ligands and IRAP active site are the most important for the ligand binding. The results propose that incorporation of adamantane and cycloalkane building blocks in the peptide chain of the hemorphin-4 scaffold is important for the potential high biological activity.
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Affiliation(s)
- Petar Todorov
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756, Sofia, Bulgaria.
| | - Petia Peneva
- Department of Organic Chemistry, University of Chemical Technology and Metallurgy, 1756, Sofia, Bulgaria
| | - Jana Tchekalarova
- Institute of Neurobiology, Bulgarian Academy of Sciences, 1113, Sofia, Bulgaria
| | - Stela Georgieva
- Department of Analytical Chemistry, University of Chemical Technology and Metallurgy, 1756, Sofia, Bulgaria
| | - Miroslav Rangelov
- Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences, 1113, Sofia, Bulgaria
| | - Nadezhda Todorova
- Institute of Biodiversity and Ecosystem Research, Bulgarian Academy of Sciences, 1113, Sofia, Bulgaria
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17
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Ali A, Alzeyoudi SAR, Almutawa SA, Alnajjar AN, Vijayan R. Molecular basis of the therapeutic properties of hemorphins. Pharmacol Res 2020; 158:104855. [PMID: 32438036 DOI: 10.1016/j.phrs.2020.104855] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 04/09/2020] [Accepted: 04/20/2020] [Indexed: 12/26/2022]
Abstract
Hemorphins are endogenous peptides, 4-10 amino acids long, belonging to the family of atypical opioid peptides released during the sequential cleavage of hemoglobin protein. Hemorphins have been shown to exhibit diverse therapeutic effects in both human and animal models. However, the precise cellular and molecular mechanisms involved in such effects remain elusive. In this review, we summarize and propose potential mechanisms based on studies that investigated the biological activity of hemorphins of different lengths on multiple therapeutic targets. Special emphasis is given to molecular events related to renin-angiotensin system (RAS), opioid receptors and insulin-regulated aminopeptidase receptor (IRAP). This review provides a comprehensive coverage of the molecular mechanisms that underpin the therapeutic potential of hemorphins. Furthermore, it highlights the role of various hemorphin residues in pathological conditions, which could be explored further for therapeutic purposes.
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Affiliation(s)
- Amanat Ali
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | | | - Shamma Abdulla Almutawa
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | - Alya Nasir Alnajjar
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates
| | - Ranjit Vijayan
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551, Al Ain, United Arab Emirates.
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18
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Ali A, Alzeyoudi SAR, Almutawa SA, Alnajjar AN, Al Dhaheri Y, Vijayan R. Camel Hemorphins Exhibit a More Potent Angiotensin-I Converting Enzyme Inhibitory Activity than Other Mammalian Hemorphins: An In Silico and In Vitro Study. Biomolecules 2020; 10:E486. [PMID: 32210030 PMCID: PMC7175181 DOI: 10.3390/biom10030486] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Revised: 03/17/2020] [Accepted: 03/20/2020] [Indexed: 02/06/2023] Open
Abstract
Angiotensin-I converting enzyme (ACE) is a zinc metallopeptidase that has an important role in regulating the renin-angiotensin-aldosterone system (RAAS). It is also an important drug target for the management of cardiovascular diseases. Hemorphins are endogenous peptides that are produced by proteolytic cleavage of beta hemoglobin. A number of studies have reported various therapeutic activities of hemorphins. Previous reports have shown antihypertensive action of hemorphins via the inhibition of ACE. The sequence of hemorphins is highly conserved among mammals, except in camels, which harbors a unique Q>R variation in the peptide. Here, we studied the ACE inhibitory activity of camel hemorphins (LVVYPWTRRF and YPWTRRF) and non-camel hemorphins (LVVYPWTQRF and YPWTQRF). Computational methods were used to determine the most likely binding pose and binding affinity of both camel and non-camel hemorphins within the active site of ACE. Molecular dynamics simulations showed that the peptides interacted with critical residues in the active site of ACE. Notably, camel hemorphins showed higher binding affinity and sustained interactions with all three subsites of the ACE active site. An in vitro ACE inhibition assay showed that the IC50 of camel hemorphins were significantly lower than the IC50 of non-camel hemorphins.
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Affiliation(s)
| | | | | | | | | | - Ranjit Vijayan
- Department of Biology, College of Science, United Arab Emirates University, PO Box 15551 Al Ain, Abu Dhabi, UAE
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Wei F, Zhao L, Jing Y. Hemoglobin-derived peptides and mood regulation. Peptides 2020; 127:170268. [PMID: 32070683 DOI: 10.1016/j.peptides.2020.170268] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 02/02/2020] [Accepted: 02/04/2020] [Indexed: 12/12/2022]
Abstract
Evidence accumulated over the past decades has revealed that red blood cells and hemoglobin (Hb) in the blood play important roles in modulating moods and emotions. The number of red blood cells affects the mood. Hb is the principal content in the red blood cells besides water. Denatured Hb is hydrolyzed to produce bioactive peptides. RVD-hemopressin α (RVD-Hpα), which is a fragment of α-chain (95-103) in Hb, functions as a negative allosteric modulator of cannabinoid receptor 1 and a positive allosteric modulator of cannabinoid receptor 2. Hemorphins, which are fragments of β-chain in Hb, exert their effects on opioid receptors. Two hemorphins, namely, LVV-hemorphin-6 and LVV-hemorphin-7, could induce anxiolytic-like effects. The use of Hb-derived bioactive peptides for the treatment of mood disorders is desirable due to cannabinoid-opioid cross modulation and the critical roles of the two systems in physiological processes, such as memory, mood and emotion.
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Affiliation(s)
- Fengmei Wei
- Department of Physiology and Psychology, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, 730000, PR China
| | - Long Zhao
- Department of Orthopaedics, Lanzhou University First Affiliated Hospital, Lanzhou, Gansu, 730000, PR China
| | - Yuhong Jing
- Institute of Anatomy and Histology & Embryology, Neuroscience, School of Basic Medical Sciences, Lanzhou University, Lanzhou, Gansu, 730000, PR China; Key Laboratory of Preclinical Study for New Drugs of Gansu Province, Lanzhou University, Lanzhou, Gansu, 730000, PR China.
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Caballero J. Considerations for Docking of Selective Angiotensin-Converting Enzyme Inhibitors. Molecules 2020; 25:molecules25020295. [PMID: 31940798 PMCID: PMC7024173 DOI: 10.3390/molecules25020295] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 01/30/2023] Open
Abstract
The angiotensin-converting enzyme (ACE) is a two-domain dipeptidylcarboxypeptidase, which has a direct involvement in the control of blood pressure by performing the hydrolysis of angiotensin I to produce angiotensin II. At the same time, ACE hydrolyzes other substrates such as the vasodilator peptide bradykinin and the anti-inflammatory peptide N-acetyl-SDKP. In this sense, ACE inhibitors are bioactive substances with potential use as medicinal products for treatment or prevention of hypertension, heart failures, myocardial infarction, and other important diseases. This review examined the most recent literature reporting ACE inhibitors with the help of molecular modeling. The examples exposed here demonstrate that molecular modeling methods, including docking, molecular dynamics (MD) simulations, quantitative structure-activity relationship (QSAR), etc, are essential for a complete structural picture of the mode of action of ACE inhibitors, where molecular docking has a key role. Examples show that too many works identified ACE inhibitory activities of natural peptides and peptides obtained from hydrolysates. In addition, other works report non-peptide compounds extracted from natural sources and synthetic compounds. In all these cases, molecular docking was used to provide explanation of the chemical interactions between inhibitors and the ACE binding sites. For docking applications, most of the examples exposed here do not consider that: (i) ACE has two domains (nACE and cACE) with available X-ray structures, which are relevant for the design of selective inhibitors, and (ii) nACE and cACE binding sites have large dimensions, which leads to non-reliable solutions during docking calculations. In support of the solution of these problems, the structural information found in Protein Data Bank (PDB) was used to perform an interaction fingerprints (IFPs) analysis applied on both nACE and cACE domains. This analysis provides plots that identify the chemical interactions between ligands and both ACE binding sites, which can be used to guide docking experiments in the search of selective natural components or novel drugs. In addition, the use of hydrogen bond constraints in the S2 and S2′ subsites of nACE and cACE are suggested to guarantee that docking solutions are reliable.
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Affiliation(s)
- Julio Caballero
- Centro de Bioinformática y Simulación Molecular (CBSM), Universidad de Talca, 1 Poniente No. 1141, Casilla 721, Talca 3460000, Chile
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