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1.
Toxicon ; 227: 107082, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36948303

RESUMO

In recent years, morbidity caused by scorpion sting of the species Tityus championi has increased in Panama. Therefore, the LD50 was determined by intravenous injection in 2.9 mg/kg and the venom of T. championi was separated using a HPLC system and their fractions were tested for biological activities in mice to identify the most toxic fractions to mammals. In addition, the venom fractions were also tested against invertebrates to look for insect-specific toxin peptides. The most toxic fractions were analyzed by MS/MS spectrometry. The primary structures of T. championi venom peptides with the most relevant activity were obtained, and the primary structure of one of most neurotoxic peptides was found at least in other four species of Tityus from Panama. This neurotoxin is quite important to be used as a protein target to be neutralized if developing antivenoms against the sting of this Panamanian scorpion or other relevant species of genera Tityus in the country.


Assuntos
Venenos de Escorpião , Peçonhas , Animais , Camundongos , Peçonhas/metabolismo , Escorpiões/química , Proteômica , Espectrometria de Massas em Tandem , Peptídeos/química , Venenos de Escorpião/química , Mamíferos/metabolismo
2.
Sci Rep ; 13(1): 2661, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792649

RESUMO

Spiders have distinct predatory behaviours selected along Araneae's evolutionary history but are mainly based on the use of venom for prey paralysis. Uloboridae spiders have lost their venom glands secondarily during evolution. Because of this, they immobilise their prey by extensively wrapping, and digestion starts with the addition of digestive fluid. During the extra-oral digestion, the digestive fluid liquefies both the prey and the AcSp2 spidroins from the web fibres. Despite the efficiency of this process, the cocktail of enzymes involved in digestion in Uloboridae spiders remains unknown. In this study, the protein content in the midgut of Uloborus sp. was evaluated through enzymatic, proteomic, and phylogenetic analysis. Hydrolases such as peptidases (endo and exopeptidases: cysteine, serine, and metallopeptidases), carbohydrases (alpha-amylase, chitinase, and alpha-mannosidase), and lipases were biochemically assayed, and 50 proteins (annotated as enzymes, structural proteins, and toxins) were identified, evidencing the identity between the digestive enzymes present in venomous and non-venomous spiders. Even enzymes thought to be unique to venom, including enzymes such as sphingomyelinase D, were found in the digestive system of non-venomous spiders, suggesting a common origin between digestive enzymes and enzymes present in venoms. This is the first characterization of the molecules involved in the digestive process and the midgut protein content of a non-venomous spider.


Assuntos
Venenos de Aranha , Aranhas , Animais , Filogenia , Aranhas/metabolismo , Peçonhas/metabolismo , Proteômica , Venenos de Aranha/química
3.
Toxicon ; 223: 107012, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36592762

RESUMO

The methylotrophic yeast Pichia pastoris has been one of the most widely used organisms in recent years as an expression system for a wide variety of recombinant proteins with therapeutic potential. Its popularity as an alternative system to Escherichia coli is mainly due to the easy genetic manipulation and the ability to produce high levels of heterologous proteins, either intracellularly or extracellularly. Being a eukaryotic organism, P. pastoris carries out post-translational modifications that allow it to produce soluble and correctly folded recombinant proteins. This work, evaluated the expression capacity in P. pastoris of two single-chain variable fragments (scFvs) of human origin, 10FG2 and LR. These scFvs were previously obtained by directed evolution against scorpion venom toxins and are able to neutralize different toxins and venoms of Mexican species. The yield obtained in P. pastoris was higher than that obtained in bacterial periplasm (E. coli), and most importantly, biochemical and functional properties were not modified. These results confirm that P. pastoris yeast can be a good expression system for the production of antibody fragments of a new recombinant antivenom.


Assuntos
Escorpiões , Peçonhas , Animais , Humanos , Escorpiões/química , Peçonhas/metabolismo , Saccharomyces cerevisiae/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes/química , Fragmentos de Imunoglobulinas/genética , Fragmentos de Imunoglobulinas/metabolismo
4.
Toxicon ; 223: 107006, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36572114

RESUMO

The genus Odontomachus is widely distributed in neotropical areas throughout Central and South America. It is a stinging ant that subdues its prey (insects) by injecting them a cocktail of toxic molecules (venom). Ant venoms are generally composed of formic acid, alkaloids, hydrocarbons, amines, peptides, and proteins. Odontomachus chelifer is an ant that inhabits neotropical regions from Mexico to Argentina. Unlike the venom of other animals such as scorpions, spiders and snakes, this ant venom has seldom been analyzed comprehensively, and their compositions are not yet completely known. In the present study, we performed a partial investigation of enzymatic and functional activities of O. chelifer ant venom, and we provide a global insight on the transcripts expressed in the venom gland to better understand their properties. The crude venom showed phospholipase A2 and antiparasitic activities. RNA sequencing (Illumina platform) of the venom gland of O. chelifer generated 61, 422, 898 reads and de novo assembly Trinity generated 50,220 contigs. BUSCO analysis against Arthropoda_db10 showed that 92.89% of the BUSCO groups have complete gene representation (single-copy or duplicated), while 4.05% are only partially recovered, and 3.06% are missing. The 30 most expressed genes in O. chelifer venom gland transcriptome included important transcripts involved in venom function such as U-poneritoxin (01)-Om1a-like (pilosulin), chitinase 2, venom allergen 3, chymotrypsin 1 and 2 and glutathione S-transferase. Analysis of the molecular function revealed that the largest number of transcripts were related to catalytic activity, including phospholipases. These data emphasize the potential of O. chelifer venom for prospection of molecules with biotechnological application.


Assuntos
Venenos de Formiga , Formigas , Animais , Transcriptoma , Formigas/genética , Venenos de Formiga/genética , Venenos de Formiga/química , Perfilação da Expressão Gênica , Peptídeos/análise , Peçonhas/metabolismo , Alérgenos
5.
Acta Trop ; 231: 106428, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35339435

RESUMO

The saturniid genus Hylesia is well known for the cutaneous lepidopterism induced by airborne setae on contact with the skin. Although several cases of such dermatitis have been reported in Argentina, no information about their venoms and toxicological implications on human health is available yet. Thus, we conducted a morphological analysis of the setae/spines and a toxinological characterization (through biological assays and proteomic techniques) of the bristle extract from caterpillars and moths of Hylesia sp. from Misiones, Argentina. By scanning electron microscopy, we revealed the various and distinctive types of urticating structures: harpoon-shaped or spiny setae in caterpillars, and setae with barb-like structures in female moths. Their venom electrophoretic profiles were substantially different, presenting proteins related to toxicity, such as serpins and serine peptidases. The female moth venom exhibited higher caseinolytic activity than the caterpillar venom, and coincidentally only the former noticeably hydrolyzed fibrinogen and gelatin. In addition, the female venom displayed a dose-dependent procoagulant effect. The injection of this venom into mouse skin led to the rapid detection of an increased number of intact and degranulated mast cells in the dermis; a few areas of focal subcutaneous hemorrhage were also observed after 5 h of injection. Altogether, this study provides relevant information about the pathophysiological mechanisms whereby Hylesia sp. from northeastern Argentina can induce toxicity on human beings, and paves the way for treatment strategies of accidents caused by this saturniid lepidopteran.


Assuntos
Mariposas , Peçonhas , Animais , Argentina , Feminino , Camundongos , Mariposas/metabolismo , Proteômica , Saúde Pública , Peçonhas/metabolismo
6.
Toxins (Basel) ; 13(2)2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33671927

RESUMO

Cell-penetrating peptides (CPPs) comprise a class of short polypeptides that possess the ability to selectively interact with the cytoplasmic membrane of certain cell types, translocate across plasma membranes and accumulate in the cell cytoplasm, organelles (e.g., the nucleus and mitochondria) and other subcellular compartments. CPPs are either of natural origin or de novo designed and synthesized from segments and patches of larger proteins or designed by algorithms. With such intrinsic properties, along with membrane permeation, translocation and cellular uptake properties, CPPs can intracellularly convey diverse substances and nanomaterials, such as hydrophilic organic compounds and drugs, macromolecules (nucleic acids and proteins), nanoparticles (nanocrystals and polyplexes), metals and radionuclides, which can be covalently attached via CPP N- and C-terminals or through preparation of CPP complexes. A cumulative number of studies on animal toxins, primarily isolated from the venom of arthropods and snakes, have revealed the cell-penetrating activities of venom peptides and toxins, which can be harnessed for application in biomedicine and pharmaceutical biotechnology. In this review, I aimed to collate examples of peptides from animal venoms and toxic secretions that possess the ability to penetrate diverse types of cells. These venom CPPs have been chemically or structurally modified to enhance cell selectivity, bioavailability and a range of target applications. Herein, examples are listed and discussed, including cysteine-stabilized and linear, α-helical peptides, with cationic and amphipathic character, from the venom of insects (e.g., melittin, anoplin, mastoparans), arachnids (latarcin, lycosin, chlorotoxin, maurocalcine/imperatoxin homologs and wasabi receptor toxin), fish (pardaxins), amphibian (bombesin) and snakes (crotamine and cathelicidins).


Assuntos
Permeabilidade da Membrana Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Peptídeos Penetradores de Células/farmacologia , Peçonhas/metabolismo , Animais , Membrana Celular/metabolismo , Peptídeos Penetradores de Células/isolamento & purificação , Peptídeos Penetradores de Células/metabolismo , Portadores de Fármacos , Humanos
7.
Neuropeptides ; 79: 101980, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31711615

RESUMO

The avulsion of nerve roots of the brachial plexus that is commonly seen in motorcycle accidents is a type of neuropathy due to deafferentation. This type of pain is clinically challenging since therapeutical protocols fail or have severe side effects. Thus, it is proposed to evaluate the antinociceptive activity of the recombinant CTK 01512-2 peptide that is derived from the venom of the Phoneutria nigriventer spider, as a future new therapeutical option. The neuropathic pain was surgically induced by avulsion of the upper brachial plexus trunk in groups of male Wistar rats and after 17 days, they were treated intrathecally with morphine, ziconotide, and CTK 01512-2. Behavioral tests were performed to evaluate mechanical and thermal hyperalgesia, cold allodynia, the functional activity of the front paw, and exploratory locomotion after the treatments. The peripheral blood samples were collected 6 h after the treatments and a comet assay was performed. The spinal cord was removed for the lipoperoxidation dosing of the membranes. The cerebrospinal fluid was analyzed for the dosage of glutamate. The recombinant peptide showed an antinociceptive effect when compared to the other drugs, without affecting the locomotor activity of the animals. Mechanical and thermal hyperalgesia, as well as cold allodynia, were reduced in the first hours of treatment. The levels of glutamate and the damage by membrane lipoperoxidation were shown to be improved, and genotoxicity was not demonstrated. In a scenario of therapeutical failures in the treatment of this type of pain, CTK 01512-2 was shown as a new effective alternative protocol. However, further testing is required to determine pharmacokinetics.


Assuntos
Analgésicos/farmacologia , Aranhas/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Peçonhas/metabolismo , Animais , Diferenciação Celular , Masculino , Morfina/farmacologia , Nociceptividade/efeitos dos fármacos , Peptídeos/farmacologia , Ratos Wistar , Aranhas/metabolismo , Medula Espinal/citologia
8.
Mar Drugs ; 17(6)2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31234371

RESUMO

Cone snails are marine gastropod mollusks with one of the most powerful venoms in nature. The toxins, named conotoxins, must act quickly on the cone snails´ prey due to the fact that snails are extremely slow, reducing their hunting capability. Therefore, the characteristics of conotoxins have become the object of investigation, and as a result medicines have been developed or are in the trialing process. Conotoxins interact with transmembrane proteins, showing specificity and potency. They target ion channels and ionotropic receptors with greater regularity, and when interaction occurs, there is immediate physiological decompensation. In this review we aimed to evaluate the structural features of conotoxins and the relationship with their target types.


Assuntos
Conotoxinas/química , Caramujo Conus/química , Caramujo Conus/metabolismo , Animais , Conotoxinas/metabolismo , Humanos , Proteínas de Membrana/metabolismo , Peçonhas/química , Peçonhas/metabolismo
9.
PLoS One ; 13(11): e0207051, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30408087

RESUMO

The galling habit represents a complex type of interaction between insects and plants, ranging from antagonism to mutualism. The obligate pollination mutualism between Ficus and fig wasps relies strongly on the induction of galls in Ficus flowers, where wasps' offspring develop. Even though gall induction plays an important role in many insect-plant interactions, the mechanisms that trigger gall formation are still not completely known. Using a fingerprinting approach, we show here that venom protein profiles from galling fig wasps differ from the venom profiles of non-galling species, suggesting the secretion plays different roles according to the type of interaction it is involved in. Each studied cleptoparasitic species had a distinct venom profile, suggesting that cleptoparasitism in fig wasps covers a vast diversity of molecular interactions. Fig wasp venoms are mainly composed of peptides. No low molecular weight compounds were detected by UPLC-DAD-MS, suggesting that such compounds (e.g., IAA and cytokinines) are not involved in gall induction. The differences in venom composition observed between galling and non-galling fig wasp species bring new perspectives to the study of gall induction processes and the role of insect secretions.


Assuntos
Ficus/fisiologia , Simbiose , Peçonhas/metabolismo , Vespas/metabolismo , Animais , Peso Molecular , Polinização , Peçonhas/química , Vespas/fisiologia
10.
Neuropeptides ; 67: 79-86, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29198480

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease that deeply affects patients, their family and society. Although scientists have made intense efforts in seeking the cure for AD, no drug available today is able to stop AD progression. In this context, compounds isolated from animal venom are potentially successful drugs for neuroprotection, since they selectively bind to nervous system targets. In this review, we presented different studies using peptides isolated from animal venom for the treatment of AD. This is a growing field that will be very helpful in understanding and even curing neurodegenerative diseases, especially AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Memória/fisiologia , Peptídeos/uso terapêutico , Peçonhas/metabolismo , Doença de Alzheimer/metabolismo , Animais , Progressão da Doença , Humanos
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