Active peptides in the skins of two hundred and thirty American amphibian species

Erspamer, V.; Erspamer, G. Falconieri; Cei, José Miguel Alfredo María

doi:10.1016/0742-8413(86)90063-0

Cited by 74 publications

(54 citation statements)

References 24 publications

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“…1 Upper). Skin extracts from this species have been previously studied and are known to contain a variety of vasoactive peptides (4). These include high levels of phyllocaerulein, phyllokinin, and phyllomedusin and moderate levels of sauvagine.…”

mentioning

confidence: 99%

Frog secretions and hunting magic in the upper Amazon: identification of a peptide that interacts with an adenosine receptor.

Daly

Caceres

Moni

et al. 1992

Proc. Natl. Acad. Sci. U.S.A.

109

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A frog used for "hunting magic" by several groups of Panoan-speaking Indians in the borderline between Brazil and Peru is identified as PhyUomedusa bicolor. This frog's skin secretion, which the Indians introduce into the body through fresh burns, is rich in peptides. These include vasoactive peptides, opioid peptides, and a peptide that we have named adenoregulin, with the sequence GLWSKIKE-VGKEAAKAAAKAAGKAALGAVSEAV as determined from mass spectrometry and Edman degradation. The natural peptide may contain a D amino acid residue, since it is not identical in chromatographic properties to the synthetic peptide. Adenoregulin enhances binding of agonists to Al adenosine receptors; it is accompanied in the skin secretion by peptides that inhibit binding. The vasoactive peptide sauvagine, the opioid peptides, and adenoregulin and related peptides affect behavior in mice and presumably contribute to the behavioral sequelae observed in humans. We here identify the frog used by the Peruvian Matses and Brazilian Mayoruna Indians as Phyllomedusa bicolor (Boddaert), a large green hylid that inhabits lowland rain forest throughout much of the Amazon basin and the Guayanan region (Fig. 1 Upper). Skin extracts from this species have been previously studied and are known to contain a variety of vasoactive peptides (4). These include high levels of phyllocaerulein, phyllokinin, and phyllomedusin and moderate levels of sauvagine. Small amounts of deltorphins, a class of opioid agonists selective for 8 receptors, also are present (5). We initially felt it unlikely that either the vasoactive peptides or the small amounts of deltorphins would account for effects on humans attributed to secretions from P. bicolor. Therefore, an examination was initiated of the effects of extracts of dried secretion from a Mayoruna frog stick.EXPERIMENTAL PROCEDURES AND RESULTS Extraction and Behavioral Effects. A stick holding dried skin secretion from P. bicolor was acquired by K.M. at the Rio Lobo site in western Brazil. The Rio Lobo stick was scraped to provide 400 mg of dried frog secretion, which was triturated first with 6 ml of methanol to yield a pale yellow methanol extract and then with 6 ml of water to yield a pale yellow aqueous extract. Extracts were stored at -20'C. Subcutaneous injection into mice of methanol and aqueous extracts in doses equivalent to 0.1-6 mg of dried secretion resulted in a dose-dependent reduction in spontaneous locomotor activity. At higher doses mice were completely inactive for several hours, although when touched they would respond briefly and then reassume a lethargic state. The aqueous extract produced a less active state at a threshold dose equivalent to 0.1 mg of dried secretion, whereas the methanol extract required a dose of 0. The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact.

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mentioning

confidence: 99%

Frog secretions and hunting magic in the upper Amazon: identification of a peptide that interacts with an adenosine receptor.

Daly

Caceres

Moni

et al. 1992

Proc. Natl. Acad. Sci. U.S.A.

109

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“…A number of approaches have been adopted to identify and isolate bioactive peptides from amphibian skin on the basis of physiological tests or bioassay. For example, contractile activity of smooth muscle preparations has enabled several peptides to be identified from a large number of amphibian species (5)(6)(7)(8). Peptide tyrosine tyrosine, synthesized primarily in the endocrine cells of the gut and in brain stem neurons (9), was isolated from a skin extract of the South American leaf frog, Phyllomedusa bicolor, on the basis of its antifungal activity (10).…”

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confidence: 99%

Isolation, Structural Characterization, and Bioactivity of a Novel Neuromedin U Analog from the Defensive Skin Secretion of the Australasian Tree Frog, Litoria caerulea

Salmon¹,

Johnsen²,

Bienert³

et al. 2000

Journal of Biological Chemistry

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We report the isolation of a novel bioactive peptide, neuromedin U-23 (NmU-23), from the defensive skin secretion of the Australasian tree frog, Litoria caerulea. The primary structure of the peptide was established by a combination of microsequencing, mass spectroscopy and site-directed antiserum immunoreactivity as SDEEVQVPGGVISNGYFLFRPRN-amide (M r 2580.6). A synthetic replicate of frog NmU-23 displaced monoradioiodinated rat NmU-23 from uterine membranes in a dose-dependent fashion indistinguishable from nonisotopically labeled rat NmU-23. In a rat uterine smooth muscle strip preparation, synthetic frog NmU-23 produced dose-dependent contractions identical to porcine NmU-25. However, in a preparation of human urinary bladder muscle strip, the synthetic frog peptide was more potent than porcine NmU-25 in eliciting contraction and produced desensitization of the preparation to the latter peptide. This report demonstrates that the defensive skin secretion of a frog contains a novel peptide exhibiting a high degree of primary structural similarity to the endogenous vertebrate peptide, NmU, and that this frog skin analog displays biological activity in mammalian tissues.

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“…Nevertheless, skin secretions of amphibians have long been considered as a rich source for biologically active peptides including hormones and neuropeptides [27][28][29]. Although many of these peptides have identical or closely related counterparts in mammalian tissues, their physiological role in the skin is generally unclear.…”

Section: Discussionmentioning

confidence: 99%

Broad spectrum antibiotic activity of skin‐PYY

Vouldoukis¹,

Shai

Nicolas

et al. 1996

FEBS Letters

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Neuropeptide Y (NPY) and polypeptide YY (PYY) are two ubiquitous neuropeptides, found in brain and intestines, respectively, where they exert important regulatory functions. In this study, a new member of the YY family recently isolated from amphibian skin, skin-PYY (SPYY), is reported to inhibit irreversibly the proliferation of a broad spectrum of pathogenic microorganisms. NPY and PYY are shown to be endowed with the same activity. Their potency is similar to that of other antibacterial peptides which have been shown to exert their function by disintegrating the bacterial membrane. These findings and the fact that the C-terminal alpha-helical domain SPYYI4-36, which is highly conserved among the family members, was responsible for killing microorganisms and for permeation of phospholipid vesicles, suggested that the antibiotic activity may emerge via a membrane permeation mechanism. These findings also raise the question whether NPY and PYY exert in vivo a similar function in mammals.

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Active peptides in the skins of two hundred and thirty American amphibian species

Cited by 74 publications

References 24 publications

Frog secretions and hunting magic in the upper Amazon: identification of a peptide that interacts with an adenosine receptor.

Frog secretions and hunting magic in the upper Amazon: identification of a peptide that interacts with an adenosine receptor.

Isolation, Structural Characterization, and Bioactivity of a Novel Neuromedin U Analog from the Defensive Skin Secretion of the Australasian Tree Frog, Litoria caerulea

Broad spectrum antibiotic activity of skin‐PYY

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