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Chai J, Wu J, Li J, Liao H, Lu W, Guo R, Shao Z, Jmel MA, Martins LA, Hackeng T, Ippel H, Dijkgraaf I, Kotsyfakis M, Xu X. Novel Amphibian Bowman-Birk-Like Inhibitor with Antioxidant and Anticoagulant Effects Ameliorates Pancreatitis Symptoms in Mice. J Med Chem 2023; 66:11869-11880. [PMID: 37610210 DOI: 10.1021/acs.jmedchem.3c00475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Acute pancreatitis (AP) is a serious inflammatory disorder and still lacks effective therapy globally. In this study, a novel Ranacyclin peptide, Ranacin, was identified from the skin of Pelophylax nigromaculatus frog. Ranacin adopted a compact β-hairpin conformation with a disulfide bond (Cys5-Cys15). Ranacin was also demonstrated effectively to inhibit trypsin and have anticoagulant and antioxidant activities in vitro. Furthermore, the severity of pancreatitis was significantly alleviated in l-Arg-induced AP mice after treatment with Ranacin. In addition, structure-activity studies of Ranacin analogues confirmed that the sequences outside the trypsin inhibitory loop (TIL), especially at the C-terminal side, might be closely associated with the efficacy of its trypsin inhibitory activity. In conclusion, our data suggest that Ranacin can improve pancreatic injury in mice with severe AP through its multi-activity. Therefore, Ranacin is considered a potential drug candidate in AP therapy.
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Affiliation(s)
- Jinwei Chai
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Jiena Wu
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Jinqiao Li
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Hang Liao
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Wancheng Lu
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Ruiyin Guo
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Zuoyan Shao
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Mohamed Amine Jmel
- Institute of Parasitology, Biology Center of the Czech Academy of Sciences, Branisovska 31, Budweis (Ceske Budejovice) 37005, Czech Republic
| | - Larissa Almeida Martins
- Institute of Parasitology, Biology Center of the Czech Academy of Sciences, Branisovska 31, Budweis (Ceske Budejovice) 37005, Czech Republic
| | - Tilman Hackeng
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Hans Ippel
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Ingrid Dijkgraaf
- Department of Biochemistry, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, 6229 ER Maastricht, The Netherlands
| | - Michail Kotsyfakis
- Institute of Parasitology, Biology Center of the Czech Academy of Sciences, Branisovska 31, Budweis (Ceske Budejovice) 37005, Czech Republic
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, N. Plastira 100, 70013 Heracklion, Crete, Greece
| | - Xueqing Xu
- Guangdong Provincial Key Laboratory of New Drug Screening, School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
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Liu WY, Zhang JT, Miyakawa T, Li GM, Gu RZ, Tanokura M. Antioxidant properties and inhibition of angiotensin-converting enzyme by highly active peptides from wheat gluten. Sci Rep 2021; 11:5206. [PMID: 33664447 PMCID: PMC7933229 DOI: 10.1038/s41598-021-84820-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 02/22/2021] [Indexed: 01/19/2023] Open
Abstract
This study aimed to focus on the high-value utilization of raw wheat gluten by determining the potent antioxidant peptides and angiotensin I-converting enzyme (ACE) inhibitory peptides from wheat gluten oligopeptides (WOP). WOP were analyzed for in vitro antioxidant activity and inhibition of ACE, and the identification of active peptides was performed by reversed-phase high-performance liquid chromatography and mass spectrometry. Quantitative analysis was performed for highly active peptides. Five potent antioxidant peptides, Leu-Tyr, Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr and Arg-Gly-Gly-Tyr (6.07 ± 0.38, 7.28 ± 0.29, 11.18 ± 1.02, 5.93 ± 0.20 and 9.04 ± 0.47 mmol 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox) equivalent/g sample, respectively), and five potent ACE inhibitory peptides, Leu-Tyr, Leu-Val-Ser, Tyr-Gln, Ala-Pro-Ser-Tyr and Arg-Gly-Gly-Tyr (half maximal inhibitory concentration (IC50) values = 0.31 ± 0.02, 0.60 ± 0.03, 2.00 ± 0.13, 1.47 ± 0.08 and 1.48 ± 0.11 mmol/L, respectively), were observed. The contents of Leu-Tyr, Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr, Arg-Gly-Gly-Tyr, and Leu-Val-Ser were 155.04 ± 8.36, 2.08 ± 0.12, 1.95 ± 0.06, 22.70 ± 1.35, 0.25 ± 0.01, and 53.01 ± 2.73 μg/g, respectively, in the WOP. Pro-Tyr, Tyr-Gln, Ala-Pro-Ser-Tyr, Arg-Gly-Gly-Tyr, and Leu-Val-Ser are novel antioxidative/ACE inhibitory peptides that have not been previously reported. The results suggest that WOP could potentially be applied in the food industry as a functional additive.
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Affiliation(s)
- Wen-Ying Liu
- College of Engineering, China Agricultural University, Beijing, 100083, People's Republic of China.
- Beijing Engineering Research Center of Protein and Functional Peptides, China National Research Institute of Food and Fermentation Industries Co., Ltd, Beijing, 100015, People's Republic of China.
| | - Jiang-Tao Zhang
- College of Life Science and Technology, HuaZhong University of Science and Technology, Wuhan, People's Republic of China
| | - Takuya Miyakawa
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan
| | - Guo-Ming Li
- Beijing Engineering Research Center of Protein and Functional Peptides, China National Research Institute of Food and Fermentation Industries Co., Ltd, Beijing, 100015, People's Republic of China
| | - Rui-Zeng Gu
- Beijing Engineering Research Center of Protein and Functional Peptides, China National Research Institute of Food and Fermentation Industries Co., Ltd, Beijing, 100015, People's Republic of China
| | - Masaru Tanokura
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo, 113-8657, Japan.
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Gitlin-Domagalska A, Maciejewska A, Dębowski D. Bowman-Birk Inhibitors: Insights into Family of Multifunctional Proteins and Peptides with Potential Therapeutical Applications. Pharmaceuticals (Basel) 2020; 13:E421. [PMID: 33255583 PMCID: PMC7760496 DOI: 10.3390/ph13120421] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/13/2020] [Accepted: 11/23/2020] [Indexed: 02/07/2023] Open
Abstract
Bowman-Birk inhibitors (BBIs) are found primarily in seeds of legumes and in cereal grains. These canonical inhibitors share a highly conserved nine-amino acids binding loop motif CTP1SXPPXC (where P1 is the inhibitory active site, while X stands for various amino acids). They are natural controllers of plants' endogenous proteases, but they are also inhibitors of exogenous proteases present in microbials and insects. They are considered as plants' protective agents, as their elevated levels are observed during injury, presence of pathogens, or abiotic stress, i.a. Similar properties are observed for peptides isolated from amphibians' skin containing 11-amino acids disulfide-bridged loop CWTP1SXPPXPC. They are classified as Bowman-Birk like trypsin inhibitors (BBLTIs). These inhibitors are resistant to proteolysis and not toxic, and they are reported to be beneficial in the treatment of various pathological states. In this review, we summarize up-to-date research results regarding BBIs' and BBLTIs' inhibitory activity, immunomodulatory and anti-inflammatory activity, antimicrobial and insecticidal strength, as well as chemopreventive properties.
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Affiliation(s)
| | | | - Dawid Dębowski
- Department of Molecular Biochemistry, Faculty of Chemistry, University of Gdansk, Wita Stwosza 63, 80-308 Gdansk, Poland; (A.G.-D.); (A.M.)
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Identification and Target-Modification of SL-BBI: A Novel Bowman-Birk Type Trypsin Inhibitor from Sylvirana latouchii. Biomolecules 2020; 10:biom10091254. [PMID: 32872343 PMCID: PMC7565067 DOI: 10.3390/biom10091254] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 01/10/2023] Open
Abstract
The peptides from the ranacyclin family share similar active disulphide loop with plant-derived Bowman-Birk type inhibitors, some of which have the dual activities of trypsin inhibition and antimicrobial. Herein, a novel Bowman-Birk type trypsin inhibitor of the ranacyclin family was identified from the skin secretion of broad-folded frog (Sylvirana latouchii) by molecular cloning method and named as SL-BBI. After chemical synthesis, it was proved to be a potent inhibitor of trypsin with a Ki value of 230.5 nM and showed weak antimicrobial activity against tested microorganisms. Modified analogue K-SL maintains the original inhibitory activity with a Ki value of 77.27 nM while enhancing the antimicrobial activity. After the substitution of active P1 site to phenylalanine and P2' site to isoleucine, F-SL regenerated its inhibitory activity on chymotrypsin with a Ki value of 309.3 nM and exhibited antiproliferative effects on PC-3, MCF-7 and a series of non-small cell lung cancer cell lines without cell membrane damage. The affinity of F-SL for the β subunits in the yeast 20S proteasome showed by molecular docking simulations enriched the understanding of the possible action mode of Bowman-Birk type inhibitors. Further mechanistic studies have shown that F-SL can activate caspase 3/7 in H157 cells and induce apoptosis, which means it has the potential to become an anticancer agent.
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Ranacyclin-NF, a Novel Bowman-Birk Type Protease Inhibitor from the Skin Secretion of the East Asian Frog, Pelophylax nigromaculatus. BIOLOGY 2020; 9:biology9070149. [PMID: 32630758 PMCID: PMC7407945 DOI: 10.3390/biology9070149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 06/19/2020] [Accepted: 06/29/2020] [Indexed: 01/10/2023]
Abstract
Serine protease inhibitors are found in plants, animals and microorganisms, where they play important roles in many physiological and pathological processes. Inhibitor scaffolds based on natural proteins and peptides have gradually become the focus of current research as they tend to bind to their targets with greater specificity than small molecules. In this report, a novel Bowman–Birk type inhibitor, named ranacyclin-NF (RNF), is described and was identified in the skin secretion of the East Asian frog, Pelophylax nigromaculatus. A synthetic replicate of the peptide was subjected to a series of functional assays. It displayed trypsin inhibitory activity with an inhibitory constant, Ki, of 447 nM and had negligible direct cytotoxicity. No observable direct antimicrobial activity was found but RNF improved the therapeutic potency of Gentamicin against Methicillin-resistant Staphylococcus aureus (MRSA). RNF shared significant sequence similarity to previously reported and related inhibitors from Odorrana grahami (ORB) and Rana esculenta (ranacyclin-T), both of which were found to be multi-functional. Two analogues of RNF, named ranacyclin-NF1 (RNF1) and ranacyclin-NF3L (RNF3L), were designed based on some features of ORB and ranacyclin-T to study structure–activity relationships. Structure–activity studies demonstrated that residues outside of the trypsin inhibitory loop (TIL) may be related to the efficacy of trypsin inhibitory activity.
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Patocka J, Nepovimova E, Klimova B, Wu Q, Kuca K. Antimicrobial Peptides: Amphibian Host Defense Peptides. Curr Med Chem 2019; 26:5924-5946. [PMID: 30009702 DOI: 10.2174/0929867325666180713125314] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 03/05/2018] [Accepted: 07/06/2018] [Indexed: 02/07/2023]
Abstract
Antimicrobial Peptides (AMPs) are one of the most common components of the innate immune system that protect multicellular organisms against microbial invasion. The vast majority of AMPs are isolated from the frog skin. Anuran (frogs and toads) skin contains abundant AMPs that can be developed therapeutically. Such peptides are a unique but diverse group of molecules. In general, more than 50% of the amino acid residues form the hydrophobic part of the molecule. Normally, there are no conserved structural motifs responsible for activity, although the vast majority of the AMPs are cationic due to the presence of multiple lysine residues; this cationicity has a close relationship with antibacterial activity. Notably, recent evidence suggests that synthesis of AMPs in frog skin may confer an advantage on a particular species, although they are not essential for survival. Frog skin AMPs exert potent activity against antibiotic-resistant bacteria, protozoa, yeasts, and fungi by permeating and destroying the plasma membrane and inactivating intracellular targets. Importantly, since they do not bind to a specific receptor, AMPs are less likely to induce resistance mechanisms. Currently, the best known amphibian AMPs are esculentins, brevinins, ranacyclins, ranatuerins, nigrocin-2, magainins, dermaseptins, bombinins, temporins, and japonicins-1 and -2, and palustrin-2. This review focuses on these frog skin AMPs and the mechanisms underlying their antimicrobial activity. We hope that this review will provide further information that will facilitate further study of AMPs and cast new light on novel and safer microbicides.
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Affiliation(s)
- Jiri Patocka
- Department of Radiology and Toxicology, Faculty of Health and Social Studies, University of South Bohemia Ceske Budejovice, Ceske Budejovice, Czech Republic
| | - Eugenie Nepovimova
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Blanka Klimova
- Faculty of Informatics and Management, University of Hradec Kralove, Hradec Kralove, Czech Republic
| | - Qinghua Wu
- College of Life Science, Institute of Biomedicine, Yangtze University, Jingzhou 434025, China
| | - Kamil Kuca
- Department of Chemistry, Faculty of Science, University of Hradec Kralove, Hradec Kralove, Czech Republic
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Miao Y, Chen G, Xi X, Ma C, Wang L, Burrows JF, Duan J, Zhou M, Chen T. Discovery and Rational Design of a Novel Bowman-Birk Related Protease Inhibitor. Biomolecules 2019; 9:biom9070280. [PMID: 31337113 PMCID: PMC6681222 DOI: 10.3390/biom9070280] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/11/2019] [Accepted: 07/12/2019] [Indexed: 01/10/2023] Open
Abstract
Anuran amphibian skin secretions are a rich source of peptides, many of which represent novel protease inhibitors and can potentially act as a source for protease inhibitor drug discovery. In this study, a novel bioactive Bowman-Birk type inhibitory hexadecapeptide of the Ranacyclin family from the defensive skin secretion of the Fukien gold-striped pond frog, Pelophlax plancyi fukienesis, was successfully isolated and identified, named PPF-BBI. The primary structure of the biosynthetic precursor was deduced from a cDNA sequence cloned from a skin-derived cDNA library, which contains a consensus motif representative of the Bowman-Birk type inhibitor. The peptide was chemically synthesized and displayed a potent inhibitory activity against trypsin (Ki of 0.17 µM), as well as an inhibitory activity against tryptase (Ki of 30.73 µM). A number of analogues of this peptide were produced by rational design. An analogue, which substituted the lysine (K) at the predicted P1 position with phenylalanine (F), exhibited a potent chymotrypsin inhibitory activity (Ki of 0.851 µM). Alternatively, a more potent protease inhibitory activity, as well as antimicrobial activity, was observed when P16 was replaced by lysine, forming K16-PPF-BBI. The addition of the cell-penetrating peptide Tat with a trypsin inhibitory loop resulted in a peptide with a selective inhibitory activity toward trypsin, as well as a strong antifungal activity. This peptide also inhibited the growth of two lung cancer cells, H460 and H157, demonstrating that the targeted modifications of this peptide could effectively and efficiently alter its bioactivity.
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Affiliation(s)
- Yuxi Miao
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland BT7 1NN, UK
| | - Guanzhu Chen
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland BT7 1NN, UK
| | - Xinping Xi
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland BT7 1NN, UK
| | - Chengbang Ma
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland BT7 1NN, UK.
| | - Lei Wang
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland BT7 1NN, UK
| | - James F Burrows
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland BT7 1NN, UK
| | - Jinao Duan
- Jiangsu Key Laboratory for Traditional Chinese Medicine (TCM) Formulae Research, Nanjing University of Chinese Medicine, Nanjing 210046, China
| | - Mei Zhou
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland BT7 1NN, UK.
| | - Tianbao Chen
- Natural Drug Discovery Group, School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland BT7 1NN, UK
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Mohajeri M, Kovanen PT, Bianconi V, Pirro M, Cicero AFG, Sahebkar A. Mast cell tryptase - Marker and maker of cardiovascular diseases. Pharmacol Ther 2019; 199:91-110. [PMID: 30877022 DOI: 10.1016/j.pharmthera.2019.03.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Accepted: 03/01/2019] [Indexed: 12/14/2022]
Abstract
Mast cells are tissue-resident cells, which have been proposed to participate in various inflammatory diseases, among them the cardiovascular diseases (CVDs). For mast cells to be able to contribute to an inflammatory process, they need to be activated to exocytose their cytoplasmic secretory granules. The granules contain a vast array of highly bioactive effector molecules, the neutral protease tryptase being the most abundant protein among them. The released tryptase may act locally in the inflamed cardiac or vascular tissue, so contributing directly to the pathogenesis of CVDs. Moreover, a fraction of the released tryptase reaches the systemic circulation, thereby serving as a biomarker of mast cell activation. Actually, increased levels of circulating tryptase have been found to associate with CVDs. Here we review the biological relevance of the circulating tryptase as a biomarker of mast cell activity in CVDs, with special emphasis on the relationship between activation of mast cells in their tissue microenvironments and the pathophysiological pathways of CVDs. Based on the available in vitro and in vivo studies, we highlight the potential molecular mechanisms by which tryptase may contribute to the pathogenesis of CVDs. Finally, the synthetic and natural inhibitors of tryptase are reviewed for their potential utility as therapeutic agents in CVDs.
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Affiliation(s)
- Mohammad Mohajeri
- Department of Medical Biotechnology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Vanessa Bianconi
- Unit of Internal Medicine, Department of Medicine, University of Perugia, Perugia, Italy
| | - Matteo Pirro
- Unit of Internal Medicine, Department of Medicine, University of Perugia, Perugia, Italy
| | - Arrigo F G Cicero
- Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy
| | - Amirhossein Sahebkar
- Biotechnology Research Center, Pharmaceutical Technology Institute, Mashhad University of Medical Sciences, Mashhad, Iran; Neurogenic Inflammation Research Center, Mashhad University of Medical Sciences, Mashhad, Iran; School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran.
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A Bowman-Birk type chymotrypsin inhibitor peptide from the amphibian, Hylarana erythraea. Sci Rep 2018; 8:5851. [PMID: 29643444 PMCID: PMC5895817 DOI: 10.1038/s41598-018-24206-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Accepted: 03/28/2018] [Indexed: 01/10/2023] Open
Abstract
The first amphibian skin secretion-derived Bowman-Birk type chymotrypsin inhibitor is described here from the Asian green frog, Hylarana erythraea, and was identified by use of molecular cloning and tandem mass spectrometric amino acid sequencing. It was named Hylarana erythraea chymotrypsin inhibitor (HECI) and in addition to inhibition of chymotrypsin (Ki = 3.92 ± 0.35 μM), the peptide also inhibited the 20 S proteasome (Ki = 8.55 ± 1.84 μM). Additionally, an analogue of HECI, named K9-HECI, in which Phe9 was substituted by Lys9 at the P1 position, was functional as a trypsin inhibitor. Both peptides exhibited anti-proliferation activity against the human cancer cell lines, H157, PC-3 and MCF-7, up to a concentration of 1 mM and possessed a low degree of cytotoxicity on normal cells, HMEC-1. However, HECI exhibited higher anti-proliferative potency against H157. The results indicate that HECI, inhibiting chymotryptic-like activity of proteasome, could provide new insights in treatment of lung cancer.
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Abstract
INTRODUCTION Tryptase is one of the main serine-proteinases located in the secretory granules of mast cells, and is released through degranulation, which is involved in the pathogenesis of allergic inflammatory disease, cardiovascular diseases, lung fibrosis and tumor. Therefore, inhibitors targeting tryptase may represent a new direction for the treatment of allergic inflammatory disease and other diseases. Areas covered: In this article, we discussed the history and development of tryptase inhibitors and described a variety of tryptase inhibitors via their structures and biological importance in clinical studies and drug development for tryptase-related diseases. Expert opinion: Initial tryptase inhibitors based on indole structure as the hydrophobic substituent on a benzylamine-piperidine template have low specificity and poor bioavailability. Therefore, designing new and specific inhibitors targeting tryptase should be involved in future clinical studies. Modifications toward indoles with varying N-substitution, introducing an amide bond, and growing the chain length contribute to an increase in the specific selectivity and potency of tryptase inhibitors. Tryptase has become the research hotspot to explore many related diseases. Therefore, there has been growing appreciation for the potential importance of the tryptase inhibitors as a target for treating these diseases.
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Affiliation(s)
- Wei-Wei Ni
- a Research Division of Clinical Pharmacology , the First Affiliated Hospital of Nanjing Medical University , Nanjing , Jiangsu , China
| | - Meng-Da Cao
- a Research Division of Clinical Pharmacology , the First Affiliated Hospital of Nanjing Medical University , Nanjing , Jiangsu , China
| | - Wen Huang
- a Research Division of Clinical Pharmacology , the First Affiliated Hospital of Nanjing Medical University , Nanjing , Jiangsu , China
| | - Ling Meng
- a Research Division of Clinical Pharmacology , the First Affiliated Hospital of Nanjing Medical University , Nanjing , Jiangsu , China
| | - Ji-Fu Wei
- a Research Division of Clinical Pharmacology , the First Affiliated Hospital of Nanjing Medical University , Nanjing , Jiangsu , China
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Woodhams DC, Bell SC, Bigler L, Caprioli RM, Chaurand P, Lam BA, Reinert LK, Stalder U, Vazquez VM, Schliep K, Hertz A, Rollins-Smith LA. Life history linked to immune investment in developing amphibians. CONSERVATION PHYSIOLOGY 2016; 4:cow025. [PMID: 27928507 PMCID: PMC5001151 DOI: 10.1093/conphys/cow025] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 05/09/2016] [Accepted: 05/14/2016] [Indexed: 05/03/2023]
Abstract
The broad diversity of amphibian developmental strategies has been shaped, in part, by pathogen pressure, yet trade-offs between the rate of larval development and immune investment remain poorly understood. The expression of antimicrobial peptides (AMPs) in skin secretions is a crucial defense against emerging amphibian pathogens and can also indirectly affect host defense by influencing the composition of skin microbiota. We examined the constitutive or induced expression of AMPs in 17 species at multiple life-history stages. We found that AMP defenses in tadpoles of species with short larval periods (fast pace of life) were reduced in comparison with species that overwinter as tadpoles and grow to a large size. A complete set of defensive peptides emerged soon after metamorphosis. These findings support the hypothesis that species with a slow pace of life invest energy in AMP production to resist potential pathogens encountered during the long larval period, whereas species with a fast pace of life trade this investment in defense for more rapid growth and development.
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Affiliation(s)
- Douglas C Woodhams
- Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA
- Corresponding author: Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA. Tel: +1 617 287 6679.
| | - Sara C Bell
- College of Marine and Environmental Sciences, James Cook University, Townsville, QLD 4811, Australia
| | - Laurent Bigler
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | - Richard M Caprioli
- Mass Spectrometry Research Center and Department of Biochemistry, Vanderbilt University, Nashville, TN 37232-8575, USA
| | - Pierre Chaurand
- Department of Chemistry, Université de Montréal, Montreal, QC, Canada H3T 1J4
| | - Brianna A Lam
- Department of Biology, James Madison University, MSC 7801, Harrisonburg, VA 22807, USA
| | - Laura K Reinert
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232-2363, USA
| | - Urs Stalder
- Department of Chemistry, University of Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
| | | | - Klaus Schliep
- Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA
| | - Andreas Hertz
- Department of Biology, University of Massachusetts Boston, 100 Morrissey Blvd., Boston, MA 02125, USA
| | - Louise A Rollins-Smith
- Department of Pathology, Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, TN 37232-2363, USA
- Department of Biological Science, Vanderbilt University, Nashville, TN 37235-1634, USA
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232-2363, USA
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A novel ranacyclin-like peptide with anti-platelet activity identified from skin secretions of the frog Amolops loloensis. Gene 2016; 576:171-5. [DOI: 10.1016/j.gene.2015.10.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Revised: 09/24/2015] [Accepted: 10/01/2015] [Indexed: 12/20/2022]
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13
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Lin Y, Hang H, Chen T, Zhou M, Wang L, Shaw C. pLR-HL: A Novel Amphibian Bowman-Birk-type Trypsin Inhibitor from the Skin Secretion of the Broad-folded Frog, Hylarana latouchii. Chem Biol Drug Des 2015; 87:91-100. [PMID: 26228512 DOI: 10.1111/cbdd.12626] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2014] [Revised: 05/01/2015] [Accepted: 07/23/2015] [Indexed: 11/30/2022]
Abstract
In this study, we report a novel heptadecapeptide (LIGGCWTKSIPPKPCLV) of the pLR/ranacyclin family, named pLR-HL, whose structure was deduced from its biosynthetic precursor-encoding cDNA cloned from the skin secretion-derived cDNA library of the broad-folded frog, Hylarana latouchii, by employing a 'shotgun' cloning technique. It contains a disulphide loop between Cys(5) and Cys(15) which is consistent with Bowman-Birk-type protease inhibitors. The primary structure of pLR-HL deduced from the cDNA sequence was confirmed by fractionating the skin secretion using reverse-phase HPLC and subsequent analysis using MALDI-TOF mass spectrometry and LC/MS/MS fragmentation sequencing. On the basis of the establishment of unequivocal amino acid sequence, a synthetic replicate was synthesized by solid-phase Fmoc chemistry, and it displayed a moderately potent trypsin inhibition with a Ki of 143 nm. The substitution of Lys-8 by Phe (Phe(8) -pLR-HL) resulted in abolition of trypsin inhibition but generation of modest inhibition on chymotrypsin with a Ki of 2.141 μm. Additionally, both the disulphide loops of pLR-HL and Phe(8) -pLR-HL were synthesized and tested. Both of the catalytic loops retained similar inhibitory potencies towards trypsin or chymotrypsin in comparison with the original intact molecules. Thus, the replacement of reactive site residues could alter the specificity of these protease inhibitors, while the canonical reactive loop alone can independently constitute biologically active moiety.
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Affiliation(s)
- Yan Lin
- Natural Drug Discovery Group, School of Pharmacy, Queen's University, Belfast, Northern Ireland, BT9 7BL, UK.,Key Laboratory for Protein and Peptide Pharmaceuticals, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Haiying Hang
- Key Laboratory for Protein and Peptide Pharmaceuticals, Institute of Biophysics, Chinese Academy of Sciences, Beijing, 100101, China
| | - Tianbao Chen
- Natural Drug Discovery Group, School of Pharmacy, Queen's University, Belfast, Northern Ireland, BT9 7BL, UK
| | - Mei Zhou
- Natural Drug Discovery Group, School of Pharmacy, Queen's University, Belfast, Northern Ireland, BT9 7BL, UK
| | - Lei Wang
- Natural Drug Discovery Group, School of Pharmacy, Queen's University, Belfast, Northern Ireland, BT9 7BL, UK
| | - Chris Shaw
- Natural Drug Discovery Group, School of Pharmacy, Queen's University, Belfast, Northern Ireland, BT9 7BL, UK
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14
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Xu X, Lai R. The chemistry and biological activities of peptides from amphibian skin secretions. Chem Rev 2015; 115:1760-846. [PMID: 25594509 DOI: 10.1021/cr4006704] [Citation(s) in RCA: 229] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Xueqing Xu
- Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences & Yunnan Province, Kunming Institute of Zoology , Kunming 650223, Yunnan, China
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15
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König E, Bininda-Emonds ORP, Shaw C. The diversity and evolution of anuran skin peptides. Peptides 2015; 63:96-117. [PMID: 25464160 DOI: 10.1016/j.peptides.2014.11.003] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 11/13/2014] [Accepted: 11/14/2014] [Indexed: 02/06/2023]
Abstract
Amphibians exhibit various, characteristic adaptations related to their "incomplete" shift from the aquatic to the terrestrial habitat. In particular, the integument was subject to a number of specialized modifications during the evolution of these animals. In this review, we place special emphasis on endogenous host-defence skin peptides from the cuteanous granular glands anuran amphibians (frogs and toads). The overview on the two broad groups of neuroactive and antimicrobial peptides (AMPs) goes beyond a simple itemization in that we provide a new perspective into the evolution and function of anuran AMPs. Briefly, these cationic, amphipathic and α-helical peptides are traditionally viewed as being part of the innate immune system, protecting the moist skin against invading microorganisms through their cytolytic action. However, the complete record of anuran species investigated to date suggests that AMPs are distributed sporadically (i.e., non-universally) across Anura. Together with the intriguing observation that virtually all anurans known to produce neuropeptides in their granular glands also co-secrete cytolytic peptides, we call the traditional role for AMPs as being purely antimicrobial into question and present an alternative scenario. We hypothesize AMPs to assist neuroactive peptides in their antipredator role through their cytolytic action increasing the delivery of the latter to the endocrine and nervous system of the predator. Thus, AMPs are more accurately viewed as cytolysins and their contribution to the immune system is better regarded as an accessory benefit.
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Affiliation(s)
- Enrico König
- AG Systematik und Evolutionsbiologie, IBU - Fakultät V, Carl von Ossietzky Universität Oldenburg, Carl von Ossietzky Strasse 9-11, 26129 Oldenburg, Germany.
| | - Olaf R P Bininda-Emonds
- AG Systematik und Evolutionsbiologie, IBU - Fakultät V, Carl von Ossietzky Universität Oldenburg, Carl von Ossietzky Strasse 9-11, 26129 Oldenburg, Germany
| | - Chris Shaw
- School of Pharmacy, Medical Biology Center, Queen's University, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland, UK
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16
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Rothemund S, Sönnichsen FD, Polte T. Therapeutic potential of the peptide leucine arginine as a new nonplant bowman-birk-like serine protease inhibitor. J Med Chem 2013; 56:6732-44. [PMID: 23988198 DOI: 10.1021/jm4005362] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The peptide leucine arginine (pLR) belongs to a new class of cyclic peptides isolated from frog skin. Its primary sequence is similar to the reactive loop of plant Bowman-Birk inhibitors (BBI), and the recently discovered circular sunflower trypsin inhibitor-1 (SFTI-1). The conformational properties of pLR in solution were determined by NMR spectroscopy and revealed excellent structural similarity to BBI and SFTI-1. Moreover, pLR is a highly potent trypsin inhibitor, with Ki values in the nanomolar range, and, due to its small size, a potential inhibitor of the serine protease tryptase. Since tryptase plays a crucial role in the development of allergic airway inflammation, the therapeutic potential of pLR in a murine asthma model was investigated. Treatment of ovalbumin-sensitized mice with pLR during allergen challenge reduced the acute asthma phenotype. Most importantly, application even at the end of a long-lasting chronic asthma model decreased the development of chronic airway inflammation and tissue remodeling.
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Affiliation(s)
- Sven Rothemund
- Interdisciplinary Center of Clinical Research, University of Leipzig , Leipzig, Germany
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17
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Ojo OO, Abdel-Wahab YHA, Flatt PR, Conlon JM. Insulinotropic Actions of the Frog Skin Host-Defense Peptide Alyteserin-2a: A Structure-Activity Study. Chem Biol Drug Des 2013; 82:196-204. [DOI: 10.1111/cbdd.12151] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Revised: 03/24/2013] [Accepted: 04/07/2013] [Indexed: 11/26/2022]
Affiliation(s)
- Opeolu O. Ojo
- School of Biomedical Sciences; University of Ulster; Cromore Road; Coleraine; BT52 1SA; UK
| | | | - Peter R. Flatt
- School of Biomedical Sciences; University of Ulster; Cromore Road; Coleraine; BT52 1SA; UK
| | - J. Michael Conlon
- Department of Biochemistry; College of Medicine and Health Sciences; United Arab Emirates University; 17666; Al-Ain; United Arab Emirates
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18
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Bi-functional peptides with both trypsin-inhibitory and antimicrobial activities are frequent defensive molecules in Ranidae amphibian skins. Amino Acids 2011; 43:309-16. [DOI: 10.1007/s00726-011-1079-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 09/06/2011] [Indexed: 11/26/2022]
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19
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Corrales J, Mulero I, Mulero V, Noga EJ. Detection of antimicrobial peptides related to piscidin 4 in important aquacultured fish. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2010; 34:331-343. [PMID: 19913049 DOI: 10.1016/j.dci.2009.11.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2009] [Revised: 11/06/2009] [Accepted: 11/08/2009] [Indexed: 05/28/2023]
Abstract
Epithelial surfaces of fish, such as the gut, skin and gills, comprise a large surface area for possible pathogen invasion. Antimicrobial peptides (AMPs), innate immunity components, play a significant role in protecting fish. Piscidins are a family of AMPs. In this study, we detected the presence of the recently discovered piscidin 4 via bug blot, Western blot, ELISA and/or immunohistochemistry in striped bass (Morone saxatilis), white bass (M. chrysops), European seabass (Dicentrarchus labrax), gilthead seabream (Sparus aurata), red drum (Sciaenops ocellatus), and barramundi (Lates calcarifer). Via bug blot, gill extracts from all species had antibacterial activity corresponding to the migration rate of piscidin 4. Western blotting showed that piscidin 4 immunoreactivity was greatest in striped bass gill extract. The concentrations of piscidin 4 detected by the ELISA in striped bass gill (approximately 20 microg/ml) were well within the levels that are inhibitory to important fish bacterial pathogens. Piscidin 4 was also detected via immunohistochemistry in all fish except barramundi. Piscidin 4-positive cells were identified as mast cells (MC), but not all MC were piscidin 4-positive. Species, age, size and physiological condition at sampling were some factors that might affect piscidin expression in different species. Our data provide strong evidence that piscidin 4 isoforms are present in all these commercially important species.
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Affiliation(s)
- Jone Corrales
- Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, 4700 Hillsborough Street, Raleigh, NC 27606, USA
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20
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Auvynet C, Joanne P, Bourdais J, Nicolas P, Lacombe C, Rosenstein Y. Dermaseptin DA4, although closely related to dermaseptin B2, presents chemotactic and Gram-negative selective bactericidal activities. FEBS J 2009; 276:6773-86. [DOI: 10.1111/j.1742-4658.2009.07392.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Conlon JM, Kolodziejek J, Nowotny N. Antimicrobial peptides from the skins of North American frogs. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2008; 1788:1556-63. [PMID: 18983817 DOI: 10.1016/j.bbamem.2008.09.018] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2008] [Revised: 09/22/2008] [Accepted: 09/26/2008] [Indexed: 11/19/2022]
Abstract
North America is home to anuran species belonging to the families Bufonidae, Eleutherodactylidae, Hylidae, Leiopelmatidae, Ranidae, and Scaphiopodidae but antimicrobial peptides have been identified only in skin secretions and/or skin extracts of frogs belonging to the Leiopelmatidae ("tailed frogs") and Ranidae ("true frogs"). Eight structurally-related cationic alpha-helical peptides with broad-spectrum antibacterial activity, termed ascaphins, have been isolated from specimens of Ascaphus truei (Leiopelmatidae) occupying a coastal range. Characterization of orthologous antimicrobial peptides from Ascaphus specimens occupying an inland range supports the proposal that this population should be regarded as a separate species A. montanus. Ascaphin-8 shows potential for development into a therapeutically valuable anti-infective agent. Peptides belonging to the brevinin-1, esculentin-1, esculentin-2, palustrin-1, palustrin-2, ranacyclin, ranatuerin-1, ranatuerin-2, and temporin families have been isolated from North American ranids. It is proposed that "ranalexins" represent brevinin-1 peptides that have undergone a four amino acid residue internal deletion. Current taxonomic recommendations divide North American frogs from the family Ranidae into two genera: Lithobates and Rana. Cladistic analysis based upon the amino acid sequences of the brevinin-1 peptides provides strong support for this assignment.
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Affiliation(s)
- J Michael Conlon
- Department of Biochemistry, Faculty of Medicine and Health Sciences, United Arab Emirates University, 17666 Al-Ain, United Arab Emirates.
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22
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Inagaki H, Akagi M, Imai HT, Taylor RW, Wiese MD, Davies NW, Kubo T. Pilosulin 5, a novel histamine-releasing peptide of the Australian ant, Myrmecia pilosula (Jack Jumper Ant). Arch Biochem Biophys 2008; 477:411-6. [DOI: 10.1016/j.abb.2008.05.014] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Accepted: 05/21/2008] [Indexed: 11/28/2022]
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23
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Song G, Zhou M, Chen W, Chen T, Walker B, Shaw C. HV-BBI--a novel amphibian skin Bowman-Birk-like trypsin inhibitor. Biochem Biophys Res Commun 2008; 372:191-6. [PMID: 18486596 DOI: 10.1016/j.bbrc.2008.05.035] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2008] [Accepted: 05/05/2008] [Indexed: 10/22/2022]
Abstract
Here we describe the isolation of a novel C-terminally amidated octadecapeptide--SVIGCWTKSIPPRPCFVK-amide--that contains a disulphide loop between Cys(5) and Cys(15) that is consistent with a Bowman-Birk type protease inhibitor, from the skin secretion of the Chinese Bamboo odorous frog, Huia versabilis. Named HV-BBI, the peptide is encoded by a single precursor of 62 amino acid residues whose primary structure was deduced from cloned skin cDNA. The precursor exhibits the typical organization of that encoding an amphibian skin peptide with a highly-conserved signal peptide, an intervening acidic amino acid residue-rich domain and a single HV-BBI-encoding domain located towards the C-terminus. A synthetic replicate of HV-BBI, with the wild-type K (Lys-8) residue in the presumed P1 position, was found to be a potent inhibitor of trypsin with a K(i) just slightly less than 19 nM. Substitution at this site with R (Arg) resulted in a significant reduction in potency (K(i) 57 nM), whereas replacement of K with F (Phe) resulted in the complete abolition of trypsin inhibitory activity. Thus, HV-BBI is a potent inhibitor of trypsin and the lysyl (K) residue that occupies the P1 position appears to be optimal for potency of action against this protease.
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Affiliation(s)
- Ganhong Song
- Molecular Therapeutics Research, School of Pharmacy, Queen's University, McClay Research Centre, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland, UK
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24
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25
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Marenah L, Flatt PR, Orr DF, Shaw C, Abdel-Wahab YHA. Characterization of naturally occurring peptides in the skin secretion of Rana pipiens frog reveal pipinin-1 as the novel insulin-releasing agent. ACTA ACUST UNITED AC 2007; 66:204-10. [PMID: 16138858 DOI: 10.1111/j.1399-3011.2005.00287.x] [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] [Indexed: 11/28/2022]
Abstract
Naturally occurring insulinotropic peptides were isolated from the skin secretions of Rana pipiens frogs. Crude secretions (50 mg; 5-10 frogs) obtained by mild electrical stimulation of the dorsal skin surface were purified by reversed-phase high-performance liquid chromatography (HPLC) yielding 80 fractions. In acute incubations with glucose-responsive BRIN-BD11 cells, fractions 40-47 (band 1) and fractions 60-65 (band 2) showed significant 1.7-6.7-fold increases in insulin-releasing activity (P < 0.001) compared with 5.6 mm glucose alone. Pooled fractions in bands 1 and 2 were rechromatographed yielding a total of seven peaks capable of subsequent 1.2-1.8-fold stimulation of insulin release. Final purification by HPLC to single homogenous peaks revealed one prominent peptide (peak 4.1) with insulin-releasing activity which lacked effects on cell viability. Electrospray mass spectrometric analysis of this peptide indicated molecular mass of 2562.6 Da. Determination of the primary amino acid sequence of this peptide revealed a 24-amino acid sequence: FLPIIAGVAAKVFPKIFCAISKKC. Database search showed a 100% homology to histamine-releasing pipinin-1. In conclusion, this study revealed the skin secretions of Rana pipiens to be a rich source of insulin-releasing peptides. The discovery of insulinotropic activity for pipinin-1, initially characterized as an antimicrobial is interesting and merits further investigation.
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Affiliation(s)
- L Marenah
- School of Biomedical Sciences, University of Ulster, Coleraine, UK.
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26
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Conceição K, Miriane Bruni F, Antoniazzi MM, Jared C, Camargo ACM, Lopes-Ferreira M, Pimenta DC. Major biological effects induced by the skin secretion of the tree frog Phyllomedusa hypochondrialis. Toxicon 2007; 49:1054-62. [PMID: 17306319 DOI: 10.1016/j.toxicon.2006.12.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2006] [Revised: 12/06/2006] [Accepted: 12/11/2006] [Indexed: 10/23/2022]
Abstract
Amphibian skin secretions contain several bioactive compounds such as biogenic amines, alkaloids, steroids, proteins and peptides; being peptides a continuously growing field of interest. This work aims to describe the main physiopathological properties of the tree frog Phyllomedusa hypochondrialis skin secretion, obtained by manual stimulation of the dorsal skin surface. Intravenous skin secretion administration provoked lethal effect in mice after 5min. Low doses induced significant systemic and local effects like edema and nociception in mice and topic administration induced myonecrosis in the endothelium of cremaster mice. The presence of phospholipase A(2) activity, proteolytic activity and creatine kinase activity (in the plasma of treated mice) are reported and are very likely to be related to the physiopathological (edematic and myotoxic) activities observed. These data provide in vivo evidence of the complex toxic effects of the P. hypochondrialis skin secretion as well as possible mechanisms of action for these effects.
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Affiliation(s)
- Katia Conceição
- LETA (Laboratório Especial de Toxinologia Aplicada) Center for Applied Toxinology (CAT/CEPID), Instituto Butantan, 05503-900 São Paulo, SP, Brazil
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27
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Conceição K, Konno K, Richardson M, Antoniazzi MM, Jared C, Daffre S, Camargo ACM, Pimenta DC. Isolation and biochemical characterization of peptides presenting antimicrobial activity from the skin of Phyllomedusa hypochondrialis. Peptides 2006; 27:3092-9. [PMID: 16963159 DOI: 10.1016/j.peptides.2006.08.005] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2006] [Revised: 08/08/2006] [Accepted: 08/09/2006] [Indexed: 11/22/2022]
Abstract
Amphibian antimicrobial peptides have been known for many decades and several of them have been isolated from anuran species. Dermaseptins are among the most studied antimicrobial peptides and are found in the skin secretion of tree frogs from the Phyllomedusinae subfamily. These peptides exert a lytic action on bacteria, protozoa, yeast, and filamentous fungi at micromolar concentrations, but unlike polylysines, present little hemolytic activity. In this work, two antimicrobial peptides were isolated from the crude skin secretion of Phyllomedusa hypochondrialis and tested against Gram-positive and Gram-negative bacteria, presenting no hemolytic activity at the tested concentrations. One of them was identified with the recently reported peptide PS-7 belonging to the phylloseptin family, and another was a novel peptide, named DPh-1, which was fully purified, sequenced by 'de novo' mass spectrometry and grouped into Dermaseptins (DPh-1).
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Affiliation(s)
- Katia Conceição
- LETA (Laboratório Especial de Toxinologia Aplicada), Center for Applied Toxinology (CAT/CEPID), Instituto Butantan, Avenida Vital Brazil 1500, São Paulo, SP, 05503-900, Brazil
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28
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Graham C, Richter SC, McClean S, O'Kane E, Flatt PR, Shaw C. Histamine-releasing and antimicrobial peptides from the skin secretions of the dusky gopher frog, Rana sevosa. Peptides 2006; 27:1313-9. [PMID: 16386333 DOI: 10.1016/j.peptides.2005.11.021] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2005] [Revised: 11/22/2005] [Accepted: 11/22/2005] [Indexed: 11/23/2022]
Abstract
Seven novel peptides were isolated from the skin secretions of the North American dusky gopher frog, Rana sevosa, on the basis of antimicrobial activity and histamine release from rat peritoneal mast cells. The peptides were purified to homogeneity using HPLC and characterized by electrospray ion-trap mass spectrometry, MALDI-TOF mass spectrometry and Edman sequencing. Bioinformatic analysis of primary structures revealed that the novel peptides could be assigned to four established families of ranid frog antimicrobial peptides, namely esculentin-1, esculentin-2, brevinin-1 and ranatuerin-2. The peptides were named in accordance with accepted terminology as ranatuerin 2SEa, etc., reflecting the peptide family name, the species of origin (SE for sevosa) and the isotype (a). Of major interest was the fact that brevinin 1SE displayed significant structural similarity to ponericin W5, an antibacterial venom peptide from the ant, Pachyconyla goeldii. This is a further example of amphibian skin defensive peptides showing striking structural similarities to peptides from insects. These data may shed some light on the functional biological relevance of defensive peptides that possess both antimicrobial and histamine-releasing activities.
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Affiliation(s)
- Ciaren Graham
- School of Biomedical Science, University of Ulster, Coleraine BT52 1SA, United Kingdom.
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29
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Pukala TL, Bowie JH, Maselli VM, Musgrave IF, Tyler MJ. Host-defence peptides from the glandular secretions of amphibians: structure and activity. Nat Prod Rep 2006; 23:368-93. [PMID: 16741585 DOI: 10.1039/b512118n] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Tara L Pukala
- Department of Chemistry, The University of Adelaide, South Australia
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30
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Shi T, Spain SM, Rabenstein DL. A Striking Periodicity of thecis/trans Isomerization of Proline Imide Bonds in Cyclic Disulfide-Bridged Peptides. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503470] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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31
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Shi T, Spain SM, Rabenstein DL. A Striking Periodicity of thecis/trans Isomerization of Proline Imide Bonds in Cyclic Disulfide-Bridged Peptides. Angew Chem Int Ed Engl 2006; 45:1780-3. [PMID: 16470897 DOI: 10.1002/anie.200503470] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Tiesheng Shi
- Department of Chemistry, University of California, Riverside, 92521, USA
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32
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Chen T, Reid CN, Walker B, Zhou M, Shaw C. Kassinakinin S: A novel histamine-releasing heptadecapeptide from frog (Kassina senegalensis) skin secretion. Biochem Biophys Res Commun 2005; 337:474-80. [PMID: 16188226 DOI: 10.1016/j.bbrc.2005.09.072] [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] [Received: 09/01/2005] [Accepted: 09/12/2005] [Indexed: 10/25/2022]
Abstract
Amphibian defensive skin secretions remain a largely untapped resource for the peptide biochemist with an interest in the identification, structural characterization, and precursor cDNA cloning of novel bioactive peptides. Here we report the isolation, structural characterization, functional profiling, and nucleotide sequence of precursor cDNA of a novel histamine-releasing heptadecapeptide, FIPVTLLALHKIKEKLN-amide, from the defensive skin secretion of the African running frog, Kassina senegalensis. This peptide was found to be a potent histamine secretagogue (EC(50) = 6 microM; maximal release = 25 microM) in a rat peritoneal mast cell model system and was accordingly named kassinakinin S. The open-reading frame of the cDNA encoding prepro-kassinakinin S was found to consist of 71 amino acid residues containing a single copy of kassinakinin S and its glycyl residue amide donor at the C-terminus. Kassinakinin S can thus be added to the growing list of amphibian skin bioactive peptide prototypes.
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Affiliation(s)
- Tianbao Chen
- School of Pharmacy, Queen's University, Belfast, Northern Ireland, UK
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33
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Graham C, Irvine AE, McClean S, Richter SC, Flatt PR, Shaw C. Peptide Tyrosine Arginine, a potent immunomodulatory peptide isolated and structurally characterized from the skin secretions of the dusky gopher frog, Rana sevosa. Peptides 2005; 26:737-43. [PMID: 15808903 DOI: 10.1016/j.peptides.2004.12.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2004] [Revised: 12/08/2004] [Accepted: 12/08/2004] [Indexed: 11/23/2022]
Abstract
An octadecapeptide was isolated from the skin secretions of the dusky gopher frog (Rana sevosa) on the basis of histamine release from rat peritoneal mast cells. This peptide was purified to homogeneity by HPLC and found to have the following primary structure, YLKGCWTKSYPPKPCFSR, using both Edman degradation chemistry and peptide sequencing using high-resolution mass spectrometry (Q-TOF MS). The peptide, named peptide Tyrosine Arginine (pYR) shares 77.8% homology with peptide Leucine Arginine (pLR). The effects of the natural amidated peptide, non-amidated peptide and C-loop region of pYR on granulopoiesis and neutrophil apoptosis were investigated. All three analogues inhibited the early development of granulocyte macrophage colonies from bone marrow stem cells but did not induce apoptosis of the end stage granulocytes, the mature neutrophil. Thus, pYR is a novel member of an important and emerging new class of amphibian peptides with hemopoietic actions.
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Affiliation(s)
- Ciaren Graham
- School of Biomedical Science, University of Ulster, Northan Ireland, Coleraine BT52 1SA, UK.
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Inagaki H, Akagi M, Imai HT, Taylor RW, Kubo T. Molecular cloning and biological characterization of novel antimicrobial peptides, pilosulin 3 and pilosulin 4, from a species of the Australian ant genus Myrmecia. Arch Biochem Biophys 2004; 428:170-8. [PMID: 15246874 DOI: 10.1016/j.abb.2004.05.013] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2004] [Revised: 05/17/2004] [Indexed: 11/19/2022]
Abstract
Venom of an Australian ant species of the Myrmecia pilosula species complex (mss. name Myrmecia banksi Taylor) contains two major allergenic peptides, pilosulin 1 and pilosulin 2. To obtain novel cDNA clones that encode the pilosulin-related bioactive peptides, mRNA of another Myrmecia species was subjected to RT-PCR in which the forward primer corresponds to a nucleotide sequence in the leader sequences of pilosulin 1 and pilosulin 2. As a result, we isolated cDNA clones encoding the novel antimicrobial peptides pilosulin 3 and pilosulin 4. The nucleotide and the amino acid sequences of all four pilosulins have high homology except for the mature peptide coding regions. Synthetic pilosulin 3 and pilosulin 4 peptides displayed antimicrobial activity with histamine-releasing and low hemolytic activities.
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Affiliation(s)
- Hidetoshi Inagaki
- Neuroscience Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan.
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Nicolas P, Vanhoye D, Amiche M. Molecular strategies in biological evolution of antimicrobial peptides. Peptides 2003; 24:1669-80. [PMID: 15019198 DOI: 10.1016/j.peptides.2003.08.017] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2003] [Accepted: 08/08/2003] [Indexed: 11/24/2022]
Abstract
Gene-encoded antimicrobial peptides that protect the skin of hylid and ranin frogs against noxious microorganisms are processed from a unique family of precursor polypeptides with a unique pattern of conserved and variable regions opposite to that of conventional secreted peptides. Precursors belonging to this family, designated the preprodermaseptin, have a common N-terminal preproregion that is remarkably well conserved both within and between species, but a hypervariable C-terminal domain corresponding to antimicrobial peptides with very different lengths, sequences, charges and antimicrobial spectra. Each frog species has its own distinct panoply of 10-20 antimicrobial peptides so that the 5000 species of ranids and hylids may produce approximately 100,000 different peptide antibiotics. The strategy that these frogs have evolved to generate this enormous array of peptides includes repeated duplications of a 150 million years old ancestral gene, focal hypermutation of the antimicrobial peptide domain maybe involving a mutagenic DNA polymerase similar to Escherichia coli Pol V, and subsequent actions of positive (diversifying) selection. The hyperdivergence of skin antimicrobial peptides can be viewed as the successful evolution of a multi-drug defense system that provides frogs with maximum protection against rapidly changing microbial biota and minimizes the chance of microorganisms developing resistance to individual peptides. The impressive variations in the expression of frog skin antimicrobial peptides may be exploited for discovering new molecules and structural motifs targeting specific microorganisms for which the therapeutic armamentarium is scarce.
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Affiliation(s)
- Pierre Nicolas
- Laboratoire de Bioactivation des Peptides, Institut Jacques Monod, 2 Place Jussieu, 75251 Paris Cedex 05, France.
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Vanhoye D, Bruston F, Nicolas P, Amiche M. Antimicrobial peptides from hylid and ranin frogs originated from a 150-million-year-old ancestral precursor with a conserved signal peptide but a hypermutable antimicrobial domain. EUROPEAN JOURNAL OF BIOCHEMISTRY 2003; 270:2068-81. [PMID: 12709067 DOI: 10.1046/j.1432-1033.2003.03584.x] [Citation(s) in RCA: 210] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The dermal glands of frogs produce antimicrobial peptides that protect the skin against noxious microorganisms and assist in wound repair. The sequences of these peptides are very dissimilar, both within and between species, so that the 5000 living anuran frogs may produce approximately 100 000 different antimicrobial peptides. The antimicrobial peptides of South American hylid frogs are derived from precursors, the preprodermaseptins, whose signal peptides and intervening sequences are remarkably conserved, but their C-terminal domains are markedly diverse, resulting in mature peptides with different lengths, sequences and antimicrobial spectra. We have used the extreme conservation in the preproregion of preprodermaseptin transcripts to identify new members of this family in Australian and South American hylids. All these peptides are cationic, amphipathic and alpha-helical. They killed a broad spectrum of microorganisms and acted in synergy. 42 preprodermaseptin gene sequences from 10 species of hylid and ranin frogs were analyzed in the context of their phylogeny and biogeography and of geophysical models for the fragmentation of Gondwana to examine the strategy that these frogs have evolved to generate an enormous array of peptide antibiotics. The hyperdivergence of modern antimicrobial peptides and the number of peptides per species result from repeated duplications of a approximately 150-million-year-old ancestral gene and accelerated mutations of the mature peptide domain, probably involving a mutagenic, error-prone, DNA polymerase similar to Escherichia coli Pol V. The presence of antimicrobial peptides with such different structures and spectra of action represents the successful evolution of multidrug defense by providing frogs with maximum protection against infectious microbes and minimizing the chance of microorganisms developing resistance to individual peptides. The hypermutation of the antimicrobial domain by a targeted mutagenic polymerase that can generate many sequence changes in a few steps may have a selective survival value when frogs colonizing a new ecological niche encounter different microbial predators.
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Affiliation(s)
- Damien Vanhoye
- Laboratoire de Bioactivation des Peptides, Institut Jacques Monod, Paris, France
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Basir YJ, Conlon JM. Peptidomic analysis of the skin secretions of the pickerel frog Rana palustris identifies six novel families of structurally-related peptides. Peptides 2003; 24:379-83. [PMID: 12732335 DOI: 10.1016/s0196-9781(03)00052-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Peptidomics methodology has been used to identify and characterize structurally 26 previously undescribed peptides in the electrically stimulated skin secretions of the North American pickerel frog Rana palustris. Peptides in the secretions were analyzed by electrospray mass spectrometry and components in mass range 700-2500 Da, present in major abundance, were purified by reverse-phase HPLC. Cysteine-containing components were identified by treatment with dithiothreitol and 4-vinylpyridine and re-analysis of the derivatizated peptide by mass spectrometry. Application of these techniques led to the identification of six families of structurally-related peptides comprising (a). six peptides containing the consensus sequence Cys-Trp-Xaa-Thr-Lys-Ser-Ile-Pro-Pro-Lys/Arg-Xaa-Cys, (b). three peptides containing the consensus sequence Pro-Pro-Gly-Val-Cys-(Xaa)(3)-Lys/Arg-Arg-Cys, (c). two peptides containing the consensus sequence Ser-Phe-His-Val-Phe-Pro-Pro-Trp-Met-Cys-Lys-Xaa-Leu-Lys-Lys-Cys, (d). two peptides containing the consensus sequence Arg-Xaa-Cys-Trp-Lys-(Xaa)(2)-Asn-(Xaa)(3)-Val-Cys-Ser, (e). nine peptides containing the consensus sequence Ser-Leu-Pro-Ala-Gly-Leu-Ser-Pro, and (f). four peptides containing the consensus sequence Asp-Xaa-Gln-Asp-Arg-Trp-Xaa-Pro. The peptides did not inhibit the growth of Escherichia coli or Staphylococcus aureus and were inactive on hamster vascular or gastric smooth muscle preparations so that their biological functions, if any, remain to be established.
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Affiliation(s)
- Yousef J Basir
- Department of Biomedical Sciences, Creighton University Medical School, Omaha, NE 68178, USA
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Ali MF, Lips KR, Knoop FC, Fritzsch B, Miller C, Conlon JM. Antimicrobial peptides and protease inhibitors in the skin secretions of the crawfish frog, Rana areolata. BIOCHIMICA ET BIOPHYSICA ACTA 2002; 1601:55-63. [PMID: 12429503 DOI: 10.1016/s1570-9639(02)00432-6] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The dorsal skin of the crawfish frog, Rana areolata, is associated with numerous prominent granular glands. Proteomic analysis of electrically stimulated skin secretions from these glands enabled the identification and characterization of eight peptides with antimicrobial and hemolytic activity belonging to the previously identified brevinin-1, temporin-1, palustrin-2, palustrin-3, esculentin-1 (two peptides), and ranatuerin-2 (two peptides) families. The primary structures of the peptides were consistent with a close phylogenetic relationship between R. areolata and the pickerel frog, Rana palustris. Three structurally related cationic, cysteine-containing peptides were identified that show sequence similarity to peptide Leucine-Arginine, a peptide with immunomodulatory and histamine-releasing properties from the skin of the northern leopard frog, Rana pipiens. The skin secretions contained a 61-amino-acid-residue peptide that inhibited porcine trypsin and possessed a 10-cysteine-residue motif that is characteristic of a protease inhibitor previously isolated from the parasitic nematode, Ascaris suum. A 48-amino-acid-residue protein containing eight cysteine residues in the whey acidic protein (WAP) motif, characteristic of elafin (skin-derived antileukoproteinase) and secretory leukocyte protease inhibitor, was also isolated. The data suggest that protease inhibitors in skin secretions may play a role complementary to cationic, amphipathic alpha-helical peptides in protecting anurans from invasions by microorganisms.
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Affiliation(s)
- Mohamed F Ali
- Department of Biomedical Sciences, Creighton University Medical School, Omaha, NE 68178, USA
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Friedman M. Application of the S-pyridylethylation reaction to the elucidation of the structures and functions of proteins. JOURNAL OF PROTEIN CHEMISTRY 2001; 20:431-53. [PMID: 11760118 DOI: 10.1023/a:1012558530359] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Cysteine (Cys) and cystine residues in proteins are unstable under conditions used for acid hydrolysis of peptide bonds. To overcome this problem, we proposed the use of the S-pyridylethylation reaction to stabilize Cys residues as pyridylethyl-cysteine (PEC) protein derivatives. This suggestion was based on our observation that two synthetic derivatives formed by pyridylethylation of the SH group of Cys with either 2-vinylpyridine (2-VP) or 4-vinylpyridine (4-VP), designated as S-beta-(2-pyridylethyl)-L-cysteine (2-PEC) and S-beta-(4-pyridylethyl)-L-cysteine (4-PEC), were stable under acid conditions used to hydrolyze proteins. This was also the case for protein-bound PEC groups. Since their discovery over 30 years ago, pyridylethylation reactions have been widely modified and automated for the analysis of many structurally different proteins at levels as low as 20 picomoles, to determine the primary structures of proteins and to define the influence of SH groups and disulfide bonds on the structures and functional, enzymatic, medical, nutritional, pharmacological, and toxic properties of proteins isolated from plant, microbial, marine, animal, and human sources. Pyridylethylation has been accepted as the best method for the modification of Cys residues in proteins for subsequent analysis and sequence determination. The reaction has also been proposed to measure D-Cys, homocysteine, glutathione, tryptophan, dehydroalanine, and furanthiol food flavors. This integrated overview of the diverse literature on these reactions emphasizes general concepts. It is intended to serve as a resource and guide for further progress based on the reported application of pyridylethylation reactions to more than 150 proteins.
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Affiliation(s)
- M Friedman
- Western Regional Research Center, Agricultural Research Service, USDA, Albany, CA 94710, USA.
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