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Mumtaz S, Behera S, Joshi S, Mukhopadhyay K. Efficacy and Toxicity Studies of Novel α-MSH Analogues with Antibiofilm Action and β-Lactam Resensitization Potential against MRSA. ACS Infect Dis 2022; 8:2480-2493. [PMID: 36440863 DOI: 10.1021/acsinfecdis.2c00280] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA), a biofilm-forming recalcitrant pathogen with a multidrug-resistant profile, poses a pandemic threat to human health and is the leading cause of severe infections in both healthcare and community settings. In this study, toward designing novel α-MSH-based peptides with enhanced activity and stability against MRSA, particularly its stationary phase and biofilm, we explored a design approach to augment the hydrophobicity of an 8-mer C-terminal α-MSH(6-13)-based peptide Ana-5 through the incorporation of a bulky unnatural amino acid. The designed Ana-peptides overcame the limitation of diminished activity in biological media and exhibited enhanced antistaphylococcal activity and cell selectivity. With membrane rupture as the primary mode of action, the peptides exhibited inhibitory potential against S. aureus biofilms. Importantly, the peptides did not exhibit any adverse effects in the in vivo toxicity studies and were also able to significantly alleviate bacterial infection in a systemic infection mice model study. Additionally, the peptides retained their activity in the presence of serum and displayed a low propensity toward resistance development in MRSA cells. Moreover, the observed synergistic potential of Ana-10 with conventional antibiotics could be vital in resurrecting discarded antibiotics. Thus, this study provides us with an exciting lead, Ana-10, for further development against biofilm-based chronic S. aureus infections.
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Affiliation(s)
- Sana Mumtaz
- Antimicrobial Research Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi110067, India
| | - Swastik Behera
- Antimicrobial Research Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi110067, India
| | - Seema Joshi
- Antimicrobial Research Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi110067, India
| | - Kasturi Mukhopadhyay
- Antimicrobial Research Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi110067, India
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2
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Binding of cationic analogues of α-MSH to lipopolysaccharide and disruption of the cytoplasmic membranes caused bactericidal action against Escherichia coli. Sci Rep 2022; 12:1987. [PMID: 35132082 PMCID: PMC8821551 DOI: 10.1038/s41598-022-05684-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 01/05/2022] [Indexed: 01/14/2023] Open
Abstract
In earlier reports, we have shown the antimicrobial activity of a host neuropeptide, alpha-melanocyte stimulating hormone (α-MSH) and its cationic analogues against Staphylococcus aureus. These analogues of α-MSH showed enhanced staphylocidal activity without any significant mammalian cell toxicity. Therefore, here, we explored the antimicrobial activity of α-MSH and its cationic analogues against Escherichia coli. Though the presence of lipopolysaccharide (LPS) in Gram-negative bacteria enables them to resist most conventional antibiotics, encouragingly α-MSH and its four analogues showed killing of both logarithmic and stationary phase E. coli cells in a time, dose and cationicity-dependent manner. In fact, the most cationic analogue, KKK-MSH with a + 5 charge, demonstrated successful eradication of 105 CFU/mL of E. coli cells within 15 min at a concentration as low as 1 µM. BC displacement experiment revealed that cationicity of the peptides was directly related to the killing efficacy of these α-MSH analogues against E. coli cells via initial LPS-binding, leading to rapid disruption of the LPS-outer membrane complex followed by inner bacterial membrane damage and eventual cell death. Here, we propose α-MSH based cationic peptides as promising future agents with broad-spectrum antibacterial efficacy against both Gram-negative and Gram-positive pathogens.
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Manavalan B, Shin TH, Kim MO, Lee G. AIPpred: Sequence-Based Prediction of Anti-inflammatory Peptides Using Random Forest. Front Pharmacol 2018; 9:276. [PMID: 29636690 PMCID: PMC5881105 DOI: 10.3389/fphar.2018.00276] [Citation(s) in RCA: 117] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 03/12/2018] [Indexed: 12/31/2022] Open
Abstract
The use of therapeutic peptides in various inflammatory diseases and autoimmune disorders has received considerable attention; however, the identification of anti-inflammatory peptides (AIPs) through wet-lab experimentation is expensive and often time consuming. Therefore, the development of novel computational methods is needed to identify potential AIP candidates prior to in vitro experimentation. In this study, we proposed a random forest (RF)-based method for predicting AIPs, called AIPpred (AIP predictor in primary amino acid sequences), which was trained with 354 optimal features. First, we systematically studied the contribution of individual composition [amino acid-, dipeptide composition (DPC), amino acid index, chain-transition-distribution, and physicochemical properties] in AIP prediction. Since the performance of the DPC-based model is significantly better than that of other composition-based models, we applied a feature selection protocol on this model and identified the optimal features. AIPpred achieved an area under the curve (AUC) value of 0.801 in a 5-fold cross-validation test, which was ∼2% higher than that of the control RF predictor trained with all DPC composition features, indicating the efficiency of the feature selection protocol. Furthermore, we evaluated the performance of AIPpred on an independent dataset, with results showing that our method outperformed an existing method, as well as 3 different machine learning methods developed in this study, with an AUC value of 0.814. These results indicated that AIPpred will be a useful tool for predicting AIPs and might efficiently assist the development of AIP therapeutics and biomedical research. AIPpred is freely accessible at www.thegleelab.org/AIPpred.
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Affiliation(s)
| | - Tae H Shin
- Department of Physiology, Ajou University School of Medicine, Suwon, South Korea.,Institute of Molecular Science and Technology, Ajou University, Suwon, South Korea
| | - Myeong O Kim
- Division of Life Science and Applied Life Science (BK21 Plus), College of Natural Sciences, Gyeongsang National University, Jinju, South Korea
| | - Gwang Lee
- Department of Physiology, Ajou University School of Medicine, Suwon, South Korea.,Institute of Molecular Science and Technology, Ajou University, Suwon, South Korea
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4
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Singh J, Joshi S, Mumtaz S, Maurya N, Ghosh I, Khanna S, Natarajan VT, Mukhopadhyay K. Enhanced Cationic Charge is a Key Factor in Promoting Staphylocidal Activity of α-Melanocyte Stimulating Hormone via Selective Lipid Affinity. Sci Rep 2016; 6:31492. [PMID: 27526963 PMCID: PMC4985751 DOI: 10.1038/srep31492] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2016] [Accepted: 07/20/2016] [Indexed: 02/07/2023] Open
Abstract
The steady rise in antimicrobial resistance poses a severe threat to global public health by hindering treatment of an escalating spectrum of infections. We have previously established the potent activity of α-MSH, a 13 residue antimicrobial peptide, against the opportunistic pathogen Staphylococcus aureus. Here, we sought to determine whether an increase in cationic charge in α-MSH could contribute towards improving its staphylocidal potential by increasing its interaction with anionic bacterial membranes. For this we designed novel α-MSH analogues by replacing polar uncharged residues with lysine and alanine. Similar to α-MSH, the designed peptides preserved turn/random coil conformation in artificial bacterial mimic 1,2-dimyristoyl-sn-glycero-3-phosphocholine:1,2-dimyristoyl-sn-glycero-3-phospho-rac-(1-glycerol) (7:3, w/w) vesicles and showed preferential insertion in the hydrophobic core of anionic membranes. Increased cationic charge resulted in considerable augmentation of antibacterial potency against MSSA and MRSA. With ~18-fold better binding than α-MSH to bacterial mimic vesicles, the most charged peptide KKK-MSH showed enhanced membrane permeabilization and depolarization activity against intact S. aureus. Scanning electron microscopy confirmed a membrane disruptive mode of action for KKK-MSH. Overall, increasing the cationic charge improved the staphylocidal activity of α-MSH without compromising its cell selectivity. The present study would help in designing more effective α-MSH-based peptides to combat clinically relevant staphylococcal infections.
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Affiliation(s)
- Jyotsna Singh
- Antimicrobial Research Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India
| | - Seema Joshi
- Antimicrobial Research Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India
| | - Sana Mumtaz
- Antimicrobial Research Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India
| | - Nancy Maurya
- Biochemistry and Environmental Toxicology Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India
| | - Ilora Ghosh
- Biochemistry and Environmental Toxicology Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India
| | - Shivangi Khanna
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi-110020, India
| | - Vivek T Natarajan
- CSIR-Institute of Genomics and Integrative Biology, Mathura Road, New Delhi-110020, India
| | - Kasturi Mukhopadhyay
- Antimicrobial Research Laboratory, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India
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5
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Grieco P, Carotenuto A, Auriemma L, Limatola A, Di Maro S, Merlino F, Mangoni ML, Luca V, Di Grazia A, Gatti S, Campiglia P, Gomez-Monterrey I, Novellino E, Catania A. Novel α-MSH peptide analogues with broad spectrum antimicrobial activity. PLoS One 2013; 8:e61614. [PMID: 23626703 PMCID: PMC3634028 DOI: 10.1371/journal.pone.0061614] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Accepted: 03/12/2013] [Indexed: 11/24/2022] Open
Abstract
Previous investigations indicate that α-melanocyte-stimulating hormone (α-MSH) and certain synthetic analogues of it exert antimicrobial effects against bacteria and yeasts. However, these molecules have weak activity in standard microbiology conditions and this hampers a realistic clinical use. The aim in the present study was to identify novel peptides with broad-spectrum antimicrobial activity in growth medium. To this purpose, the Gly10 residue in the [DNal(2′)-7, Phe-12]-MSH(6–13) sequence was replaced with conventional and unconventional amino acids with different degrees of conformational rigidity. Two derivatives in which Gly10 was replaced by the residues Aic and Cha, respectively, had substantial activity against Candida strains, including C. albicans, C. glabrata, and C. krusei and against gram-positive and gram-negative bacteria. Conformational analysis indicated that the helical structure along residues 8–13 is a key factor in antimicrobial activity. Synthetic analogues of α-MSH can be valuable agents to treat infections in humans. The structural preferences associated with antimicrobial activity identified in this research can help further development of synthetic melanocortins with enhanced biological activity.
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Affiliation(s)
- Paolo Grieco
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | | | - Luigia Auriemma
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Antonio Limatola
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Salvatore Di Maro
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Francesco Merlino
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Maria Luisa Mangoni
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Biochemical Science, ‘A. Rossi Fanelli’, University of Rome ‘La Sapienza’, Rome, Italy
| | - Vincenzo Luca
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Biochemical Science, ‘A. Rossi Fanelli’, University of Rome ‘La Sapienza’, Rome, Italy
| | - Antonio Di Grazia
- Istituto Pasteur-Fondazione Cenci Bolognetti, Department of Biochemical Science, ‘A. Rossi Fanelli’, University of Rome ‘La Sapienza’, Rome, Italy
| | - Stefano Gatti
- Center for Preclinical Investigation, Fondazione IRCCS Ca'Granda - Ospedale Maggiore Policlinico, Milano, Italy
| | - Pietro Campiglia
- Department of Pharmaceutical Science, University of Salerno, Fisciano, Salerno, Italy
| | | | - Ettore Novellino
- Department of Pharmacy, University of Naples Federico II, Naples, Italy
| | - Anna Catania
- Center for Preclinical Investigation, Fondazione IRCCS Ca'Granda - Ospedale Maggiore Policlinico, Milano, Italy
- * E-mail:
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7
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Rauch I, Holzmeister S, Kofler B. Anti-Candida activity of alpha-melanocyte-stimulating hormone (alpha-MSH) peptides. J Leukoc Biol 2008; 85:371-2; author reply 373. [PMID: 19092131 DOI: 10.1189/jlb.1008614] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Previously, alpha-MSH, a 13-amino acid neuropeptide and the tripeptide alpha-MSH have been shown to possess potent antimicrobial properties. We performed microplate based growth inhibition assays on C. albicans with alpha-MSH, but could not observe any growth inhibiting effect. Repeating the originally published assay with different C. albicans strains, we detected a mild growth inhibiting effect of 100 microM alpha-MSH, but again no effect of alpha-MSH.
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8
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Charnley M, Moir AJG, Douglas CWI, Haycock JW. Anti-microbial action of melanocortin peptides and identification of a novel X-Pro-D/L-Val sequence in Gram-positive and Gram-negative bacteria. Peptides 2008; 29:1004-9. [PMID: 18355945 DOI: 10.1016/j.peptides.2008.02.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 02/01/2008] [Accepted: 02/07/2008] [Indexed: 01/28/2023]
Abstract
The melanocortin peptides alpha-MSH, Lys-Pro-Val and Lys-Pro-D-Val are known to be potent anti-inflammatory agents; however their role as antibacterial peptides is less clear. The aim of this study was to determine whether these peptides displayed antibacterial properties, and specifically whether the Lys-Pro-D-Val tripeptide was more potent than Lys-Pro-Val, consistent with their anti-inflammatory actions. alpha-MSH, Ac-Lys-Pro-D-Val-NH2 and Ac-Lys-Pro-Val-NH2 were found to be antibacterial against both Gram-positive and Gram-negative bacteria (Staphylococcus aureus and Escherichia coli) over a broad range of concentrations compared to a control peptide, Ac-Ala-Ala-Ala-NH2. However, the relative potency of alpha-MSH, Ac-Lys-Pro-D-Val-NH2, Ac-Lys-Pro-Val-NH2 did not differ. Furthermore, it was found that the cationic charge on the lysine residue was not required for activity as a variant peptide Ac-Ala-Pro-D-Val-NH2 was also antibacterial. We therefore describe a novel X-Pro-D/L-Val peptide sequence with similarity to the short melanocortin peptides, which possess antibacterial activity. The combined anti-inflammatory and antibacterial action of such peptides may also have potential value therapeutically.
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Affiliation(s)
- Mirren Charnley
- Department of Engineering Materials, Kroto Research Institute, University of Sheffield, Sheffield S3 7HQ, UK
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9
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Masman MF, Somlai C, Garibotto FM, Rodríguez AM, de la Iglesia A, Zacchino SA, Penke B, Enriz RD. Structure-antifungal activity relationship of His-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2 and analogues. Bioorg Med Chem 2008; 16:4347-58. [PMID: 18346897 DOI: 10.1016/j.bmc.2008.02.072] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Revised: 02/20/2008] [Accepted: 02/22/2008] [Indexed: 11/28/2022]
Abstract
The synthesis, in vitro evaluation and conformational study of His-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH(2) and analogues acting as antifungal agents are reported. Among them, His-Phe-Lys-Trp-Gly-Arg-Phe-Val-NH(2) exhibited a moderate but significant antifungal activity against Cryptococcus neoformans, Candida albicans and Candida tropicalis. A theoretical study allows us to propose a biologically relevant conformation for these octapeptides acting as antifungal agents. In addition, these theoretical calculations allow us to determine the minimal structural requirements to produce the antifungal response and can provide a guide for the design of compounds with this biological activity.
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Affiliation(s)
- Marcelo F Masman
- Departamento de Química, Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco 915, 5700 San Luis, Argentina
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10
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Carotenuto A, Saviello MR, Auriemma L, Campiglia P, Catania A, Novellino E, Grieco P. Structure-function relationships and conformational properties of alpha-MSH(6-13) analogues with candidacidal activity. Chem Biol Drug Des 2007; 69:68-74. [PMID: 17313459 DOI: 10.1111/j.1747-0285.2007.00473.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Alpha-melanocyte-stimulating hormone (alpha-MSH) is an endogenous linear tridecapeptide with potent anti-inflammatory effects. We firstly demonstrated that alpha-MSH and its C-terminal sequence Lys-Pro-Val [alpha-MSH(11-13)] have antimicrobial effects against two major and representative pathogens: Staphylococcus aureus and Candida albicans. Successively, in an attempt to improve the candidacidal activity of alpha-MSH and to better understand the peptide structure-antifungal activity relations, we have recently designed and synthesized novel peptide analogues. We focused on the sequence alpha-MSH(6-13), which contains the invariant melanocortin core sequence His-Phe-Arg-Trp (6-9) and also contains the sequence Lys-Pro-Val (11-13) important for antimicrobial activity. In that structure-activity study, we discovered several compounds that have greater candidacidal activity than alpha-MSH, among which the peptide [d-Nal-7,Phe-12]-alpha-MSH(6-13) was the most potent. Here, we report a detailed conformational analysis by spectroscopic and computational methods of three peptides, alpha-MSH(6-13) (1), [d-Nal-7,Phe-12]-alpha-MSH(6-13) (2) and [d-Nal-7,Asp-12]-alpha-MSH(6-13) (3). Peptides were chosen on the basis of their candidacidal activities and were studied in membrane mimetic environment (SDS micelles). Different turn structures were observed for the three peptides and a conformation-activity model was developed based on these results. This study offers a structural basis for the design of novel peptide and non-peptide analogues to be used as new antimicrobial agents.
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Affiliation(s)
- Alfonso Carotenuto
- Department of Pharmaceutical and Toxicological Chemistry, University of Naples Federico II, Via D. Montesano 49, I-80131 Naples, Italy
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11
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Nagarajan V, Kaushik N, Murali B, Zhang C, Lakhera S, Elasri MO, Deng Y. A Fourier transformation based method to mine peptide space for antimicrobial activity. BMC Bioinformatics 2006; 7 Suppl 2:S2. [PMID: 17118141 PMCID: PMC1683563 DOI: 10.1186/1471-2105-7-s2-s2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Background Naturally occurring antimicrobial peptides are currently being explored as potential candidate peptide drugs. Since antimicrobial peptides are part of the innate immune system of every living organism, it is possible to discover new candidate peptides using the available genomic and proteomic data. High throughput computational techniques could also be used to virtually scan the entire peptide space for discovering out new candidate antimicrobial peptides. Result We have identified a unique indexing method based on biologically distinct characteristic features of known antimicrobial peptides. Analysis of the entries in the antimicrobial peptide databases, based on our indexing method, using Fourier transformation technique revealed a distinct peak in their power spectrum. We have developed a method to mine the genomic and proteomic data, for the presence of peptides with potential antimicrobial activity, by looking for this distinct peak. We also used the Euclidean metric to rank the potential antimicrobial peptides activity. We have parallelized our method so that virtually any given protein space could be data mined, in search of antimicrobial peptides. Conclusion The results show that the Fourier transform based method with the property based coding strategy could be used to scan the peptide space for discovering new potential antimicrobial peptides.
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Affiliation(s)
- Vijayaraj Nagarajan
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Navodit Kaushik
- Department of Computer Science, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Beddhu Murali
- Department of Computer Science, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Chaoyang Zhang
- Department of Computer Science, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Sanyogita Lakhera
- Department of Mathematics, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Mohamed O Elasri
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
| | - Youping Deng
- Department of Biological Sciences, The University of Southern Mississippi, Hattiesburg, MS, 39406, USA
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Millington GWM. Proopiomelanocortin (POMC): the cutaneous roles of its melanocortin products and receptors. Clin Exp Dermatol 2006; 31:407-12. [PMID: 16681590 DOI: 10.1111/j.1365-2230.2006.02128.x] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The precursor protein proopiomelanocortin (POMC) produces many biologically active peptides via a series of enzymatic steps in a tissue-specific manner, yielding the melanocyte-stimulating hormones (MSHs), corticotrophin (ACTH) and beta-endorphin. The gene for alpha-MSH is encoded for by the POMC gene, but alpha-MSH cannot be produced from POMC gene transcription and translation without these specific post-translational proteolytic steps taking place. The MSHs and ACTH bind to the extracellular G-protein-coupled melanocortin receptors (MCR), of which there are five subtypes. Two (MC1R and MC5R) show widespread cutaneous expression. ACTH and alpha-MSH bind to MC1R to influence both pigmentation and the immune system. MC5R regulates the sebaceous glands. Mutations in the MC1R gene lead to fair skin and red hair in humans, which is also seen with inactivating human POMC gene mutations. MC1R mutant receptor expression can also correlate with an increased incidence of the three commonest forms of skin cancer. Other mutations can occur in the POMC system or parallel interacting pathways, such as in prohormone convertase 1 and agouti signalling protein, a human homologue of murine agouti protein. However, they do not necessarily affect skin colour or function in humans, and further studies are needed to clarify these observations.
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Affiliation(s)
- G W M Millington
- Department of Dermatology, Norfolk and Norwich University Hospital, Colney Lane, Norwich, UK.
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13
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Masman MF, Rodríguez AM, Svetaz L, Zacchino SA, Somlai C, Csizmadia IG, Penke B, Enriz RD. Synthesis and conformational analysis of His-Phe-Arg-Trp-NH2 and analogues with antifungal properties. Bioorg Med Chem 2006; 14:7604-14. [PMID: 16926096 DOI: 10.1016/j.bmc.2006.07.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Accepted: 07/01/2006] [Indexed: 11/30/2022]
Abstract
The synthesis, in vitro evaluation, and conformational study of His-Phe-Arg-Trp-NH2 and related derivatives acting as antifungal agents are reported. Among them, His-Phe-Arg-Trp-NH2 and His-Tyr-Arg-Trp-NH2 exhibited antifungal activity against Cryptococcus neoformans. Antifungal activity of these compounds appears to be closely related to the alpha-MSH effect. A conformational and electronic study allows us to propose a biologically relevant conformation for these tetrapeptides acting as antifungal agents. In addition, these theoretical calculations permit us to determine the minimal structural requirements to produce the antifungal response and may provide a guide for the design of compounds with this biological activity.
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Affiliation(s)
- Marcelo F Masman
- Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco 915, 5700 San Luis, Argentina
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14
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Gatti S, Carlin A, Sordi A, Leonardi P, Colombo G, Fassati LR, Lipton JM, Catania A. Inhibitory Effects of the Peptide (CKPV)2 on Endotoxin-Induced Host Reactions. J Surg Res 2006; 131:209-14. [PMID: 16413580 DOI: 10.1016/j.jss.2005.08.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2005] [Revised: 07/29/2005] [Accepted: 08/04/2005] [Indexed: 11/19/2022]
Abstract
BACKGROUND alpha-Melanocyte stimulating hormone (alpha-MSH) is an endogenous peptide that has remarkable anti-inflammatory and antimicrobial effects. These activities have been traced to the C-terminal tripeptide Lys-Pro-Val (KPV). A dimer composed of two KPV sequences connected with a Cys-Cys linker, (CKPV)2, is currently under clinical investigation for antimicrobial use. The present research was designed to evaluate effects of (CKPV)(2) on endotoxin-induced host reactions in vitro and in vivo. MATERIALS AND METHODS Effects of (CKPV)2, KPV, and [Nle4-dPhe7]-alpha-MSH (NDP-alpha-MSH) on tumor necrosis factor alpha (TNF-alpha) production were determined: 1) in human peripheral blood mononuclear cells (PBMC) stimulated with lipopolysaccharide (LPS) in vitro, and 2) in rats injected with LPS i.v. and sacrificed at 1 h. In additional experiments, dialysis peritonitis was induced in rats by adding LPS to dialysis fluid. Net ultrafiltrate was calculated and concentrations of nitrite (NO2-) and TNF-alpha were measured in blood and peritoneal fluid at 7 h. RESULTS (CKPV)2 inhibited TNF-alpha production by LPS-stimulated human PBMC. This small peptide was as effective as NDP-alpha-MSH and more potent than KPV. Similar effectiveness was observed in vivo: 1 h after LPS injection, the large increase in circulating TNF-alpha was markedly reduced by (CKPV)2 treatment. In LPS-induced peritonitis, (CKPV)2 restored net ultrafiltrate to control values and significantly inhibited concentrations of TNF-alpha and NO2- both in plasma and in dialysate. CONCLUSIONS The remarkable capacity of (CKPV)2 to inhibit endotoxin-induced host reactions suggests that it may be useful in treatment of inflammatory disorders.
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Affiliation(s)
- Stefano Gatti
- Department of Liver Transplantation, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Milano, Italy
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