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1.
Acta sci., Biol. sci ; 44: e49794, mar. 2022. graf, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1413430

RESUMO

Arthropod venoms are potential sources of bioactive substances, providing tools for the validation of popular use and new drugs design. Ants belonging to the genus Dinoponera are used in the folk medicine to treat inflammatory conditions. It was previously demonstrated that the venom of the giant ant Dinoponera quadriceps (DqV), containing a mixture of polypeptides, elicit antinociceptive effect in mice models of chemical, mechanical and thermal nociception. The aim of this study was to evaluate DqV antiinflammatory and antihypernociceptive effects in a mice model of traumatic cutaneous wound. Colonies of D. quadriceps were collected in the 'Serra de Maranguape' (State of Ceará, northeastern Brazil), a small mountain range located on the coastal zone, and the venom secreted by the ant glands was extracted with capillary tubes, further lyophilized and maintained at -20 ± 1ºC until use. Wounds were performed in the dorsum of Swiss mice. Animals received intravenous (i.v.) injection of DqV (50 µg kg-1 day-1) during 3 days for evaluation of inflammatory parameters present in the wounds: hypernociception, leukocyte infiltrate, myeloperoxidase activity, nitrite/nitrate content. Data was tested by two-way ANOVA and Bonferroni's post-hoc test. DqV reduced (2.7 folds) hypernociception at 48 hours, leukocyte infiltration by 65% at 6 hours and myeloperoxidase activity by 60% at 0.5 hour after wound induction. In conclusion, the venom extracted from D. quadriceps glands attenuates inflammation and hypernociception in mice cutaneous wounds.(AU)


Assuntos
Animais , Camundongos , Venenos de Artrópodes/análise , Inflamação/tratamento farmacológico , Camundongos/lesões , Cicatrização/efeitos dos fármacos
2.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 26: e20190079, May 29, 2020. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-29956

RESUMO

Background:Scolopendra polymorpha (S. polymorpha) is a predatory centipede whose venom contains a multiplicity of biochemical effectors that can cause muscle damage and cumulative cell destruction in its prey. Despite previous investigations of S. polymorpha and other centipede venoms, there is a lack of information on the morphological and biochemical patterns elicited by their myotoxic effects. To elucidate these processes, this paper presents evidence of skeletal muscle damage, and alterations in key biochemical mediators that appear only after exposure to centipede venom.Methods:Venom was collected and fractionated using RP-HPLC; mouse extensor digitorum longus (EDL) muscle was exposed to whole venom and venom fractions to evaluate myotoxicity by means of creatine kinase (CK) - a muscle damage marker - activity measurements and histochemical analysis.Results:CK activity was higher in EDL muscle exposed to venom than in unexposed muscle. This increase was observed after 15 min of venom incubation, and remained stable up to 45 min. Venom-exposed EDL muscle showed signs of muscle damage including necrosis, loss of fascicular structure as well as mitochondrial accumulations and ragged red fibers (RRF), suggesting an impairment in the normal mitochondrial arrangement. Nicotinamide adenine dinucleotide (NADH) and cytochrome oxidase (COX) tests also indicate that respiratory complexes might be affected.Conclusion:Our results suggest a different biochemical composition of S. polymorpha venom, based on the different effects of four venom fractions on the cells tested, according to statistical evidence. Fractions F6 and F7 caused the most important alterations.(AU)


Assuntos
Animais , Camundongos , Mitocôndrias/fisiologia , Venenos de Artrópodes/análise , Músculos/fisiopatologia , Artrópodes
3.
Acta Sci. Biol. Sci. ; 42: e47680, fev. 2020. ilus, graf
Artigo em Inglês | VETINDEX | ID: vti-26799

RESUMO

Arthropod venoms are potential sources of bioactive substances, providing tools for the validation of popular use and new drugs design. Ants belonging to the genus Dinoponera are used in the folk medicine to treat inflammatory conditions. It was previously demonstrated that the venom of the giant ant Dinoponera quadriceps (DqV), containing a mixture of polypeptides, elicit antinociceptive effect in mice models of chemical, mechanical and thermal nociception. The aim of this study was to evaluate DqV antiinflammatory and antihypernociceptive effects in a mice model of traumatic cutaneous wound. Colonies of D. quadriceps were collected in the ‘‘Serra de Maranguape (State of Ceará, northeastern Brazil), a small mountain range located on the coastal zone, and the venom secreted by the ant glands was extracted with capillary tubes, further lyophilized and maintained at -20 ± 1ºC until use. Wounds were performed in the dorsum of Swiss mice. Animals received intravenous (i.v.) injection of DqV (50 µg -1kg day-1) during 3 days for evaluation of inflammatory parameters present in the wounds: hypernociception, leukocyte infiltrate, myeloperoxidase activity, nitrite nitrate-1 content. Data was tested by two-way ANOVA and Bonferronis post-hoc test. DqV reduced (2.7 folds) hypernociception at 48 hours, leukocyte infiltration by 65% at 6 hours and myeloperoxidase activity by 60% at 0.5 hour after wound induction. In conclusion, the venom extracted from D. quadriceps glands attenuates inflammation and hypernociception in mice cutaneous wounds.(AU)


Assuntos
Animais , Camundongos , Venenos de Artrópodes/análise , Himenópteros , Camundongos/lesões , Cicatrização , Anti-Inflamatórios
4.
Acta sci., Biol. sci ; Acta sci., Biol. sci;42: e47680, fev. 2020. ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460930

RESUMO

Arthropod venoms are potential sources of bioactive substances, providing tools for the validation of popular use and new drugs design. Ants belonging to the genus Dinoponera are used in the folk medicine to treat inflammatory conditions. It was previously demonstrated that the venom of the giant ant Dinoponera quadriceps (DqV), containing a mixture of polypeptides, elicit antinociceptive effect in mice models of chemical, mechanical and thermal nociception. The aim of this study was to evaluate DqV antiinflammatory and antihypernociceptive effects in a mice model of traumatic cutaneous wound. Colonies of D. quadriceps were collected in the ‘‘Serra de Maranguape’’ (State of Ceará, northeastern Brazil), a small mountain range located on the coastal zone, and the venom secreted by the ant glands was extracted with capillary tubes, further lyophilized and maintained at -20 ± 1ºC until use. Wounds were performed in the dorsum of Swiss mice. Animals received intravenous (i.v.) injection of DqV (50 µg -1kg day-1) during 3 days for evaluation of inflammatory parameters present in the wounds: hypernociception, leukocyte infiltrate, myeloperoxidase activity, nitrite nitrate-1 content. Data was tested by two-way ANOVA and Bonferroni’s post-hoc test. DqV reduced (2.7 folds) hypernociception at 48 hours, leukocyte infiltration by 65% at 6 hours and myeloperoxidase activity by 60% at 0.5 hour after wound induction. In conclusion, the venom extracted from D. quadriceps glands attenuates inflammation and hypernociception in mice cutaneous wounds.


Assuntos
Animais , Camundongos , Camundongos/lesões , Cicatrização , Himenópteros , Venenos de Artrópodes/análise , Anti-Inflamatórios
5.
Toxins (Basel) ; 11(10)2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31557900

RESUMO

Arthropoda is a phylum of invertebrates that has undergone remarkable evolutionary radiation, with a wide range of venomous animals. Arthropod venom is a complex mixture of molecules and a source of new compounds, including antimicrobial peptides (AMPs). Most AMPs affect membrane integrity and produce lethal pores in microorganisms, including protozoan pathogens, whereas others act on internal targets or by modulation of the host immune system. Protozoan parasites cause some serious life-threatening diseases among millions of people worldwide, mostly affecting the poorest in developing tropical regions. Humans can be infected with protozoan parasites belonging to the genera Trypanosoma, Leishmania, Plasmodium, and Toxoplasma, responsible for Chagas disease, human African trypanosomiasis, leishmaniasis, malaria, and toxoplasmosis. There is not yet any cure or vaccine for these illnesses, and the current antiprotozoal chemotherapeutic compounds are inefficient and toxic and have been in clinical use for decades, which increases drug resistance. In this review, we will present an overview of AMPs, the diverse modes of action of AMPs on protozoan targets, and the prospection of novel AMPs isolated from venomous arthropods with the potential to become novel clinical agents to treat protozoan-borne diseases.


Assuntos
Anti-Infecciosos/farmacologia , Venenos de Artrópodes/análise , Leishmania/efeitos dos fármacos , Peptídeos/farmacologia , Plasmodium/efeitos dos fármacos , Trypanosoma/efeitos dos fármacos , Anti-Infecciosos/uso terapêutico , Venenos de Artrópodes/farmacologia , Humanos , Sistema Imunitário/efeitos dos fármacos , Peptídeos/uso terapêutico
6.
J. Venom. Anim. Toxins incl. Trop. Dis. ; 21: 1-12, Nov. 10, 2015. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-759972

RESUMO

Hyaluronidases are enzymes that mainly degrade hyaluronan, the major glycosaminoglycan of the interstitial matrix. They are involved in several pathological and physiological activities including fertilization, wound healing, embryogenesis, angiogenesis, diffusion of toxins and drugs, metastasis, pneumonia, sepsis, bacteremia, meningitis, inflammation and allergy, among others. Hyaluronidases are widely distributed in nature and the enzymes from mammalian spermatozoa, lysosomes and animal venoms belong to the subclass EC 3.2.1.35. To date, only five three-dimensional structures for arthropod venom hyaluronidases (Apis mellifera and Vespula vulgaris) were determined. Additionally, there are four molecular models for hyaluronidases fromMesobuthus martensii, Polybia paulista and Tityus serrulatus venoms. These enzymes are employed as adjuvants to increase the absorption and dispersion of other drugs and have been used in various off-label clinical conditions to reduce tissue edema. Moreover, a PEGylated form of a recombinant human hyaluronidase is currently under clinical trials for the treatment of metastatic pancreatic cancer. This review focuses on the arthropod venom hyaluronidases and provides an overview of their biochemical properties, role in the envenoming, structure/activity relationship, and potential medical and biotechnological applications.(AU)


Assuntos
Animais , Venenos de Artrópodes/análise , Venenos de Artrópodes/uso terapêutico , Animais Peçonhentos , Hialuronoglucosaminidase
7.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;21: 1-12, 31/03/2015. ilus, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1484615

RESUMO

Hyaluronidases are enzymes that mainly degrade hyaluronan, the major glycosaminoglycan of the interstitial matrix. They are involved in several pathological and physiological activities including fertilization, wound healing, embryogenesis, angiogenesis, diffusion of toxins and drugs, metastasis, pneumonia, sepsis, bacteremia, meningitis, inflammation and allergy, among others. Hyaluronidases are widely distributed in nature and the enzymes from mammalian spermatozoa, lysosomes and animal venoms belong to the subclass EC 3.2.1.35. To date, only five three-dimensional structures for arthropod venom hyaluronidases (Apis mellifera and Vespula vulgaris) were determined. Additionally, there are four molecular models for hyaluronidases fromMesobuthus martensii, Polybia paulista and Tityus serrulatus venoms. These enzymes are employed as adjuvants to increase the absorption and dispersion of other drugs and have been used in various off-label clinical conditions to reduce tissue edema. Moreover, a PEGylated form of a recombinant human hyaluronidase is currently under clinical trials for the treatment of metastatic pancreatic cancer. This review focuses on the arthropod venom hyaluronidases and provides an overview of their biochemical properties, role in the envenoming, structure/activity relationship, and potential medical and biotechnological applications.


Assuntos
Animais , Animais Peçonhentos , Hialuronoglucosaminidase , Venenos de Artrópodes/análise , Venenos de Artrópodes/uso terapêutico
8.
Toxicon ; 49(5): 663-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17188732

RESUMO

Lonomia obliqua envenomation induces an intense burning sensation at the site of contact and severe hemorrhage followed by edema and hypotension, and after few days death can occur usually due to acute renal failure. In order to understand more about the envenomation syndrome, the present study investigates the role played by kallikrein-kinin system (KKS) in edematogenic and hypotensive responses to the envenomation by L. obliqua. The incubation of L. obliqua caterpillar bristles extract (LOCBE) with plasma results in kallikrein activation, measured by cromogenic assay using the kallikrein synthetic substrate S-2302 (H-D-Pro-Phe-Arg-pNA). It was also showed that LOCBE was able to release kinins from low-molecular weight kininogen (LMWK). Moreover, it was demonstrated that previous administration of a kallikrein inhibitor (aprotinin) or bradykinin B2 receptor antagonist (HOE-140) significantly reduces the edema and hypotension in response to LOCBE, using mouse paw edema bioassay and mean arterial blood pressure analysis, respectively. The results demonstrate a direct involvement of the KKS in the edema formation and in the fall of arterial pressure that occur in the L. obliqua envenomation syndrome.


Assuntos
Venenos de Artrópodes/toxicidade , Edema/induzido quimicamente , Hipotensão/induzido quimicamente , Mordeduras e Picadas de Insetos/metabolismo , Sistema Calicreína-Cinina/efeitos dos fármacos , Mariposas/química , Análise de Variância , Animais , Venenos de Artrópodes/análise , Pressão Sanguínea/efeitos dos fármacos , Feminino , Cobaias , Cininogênios , Larva/química , Masculino , Camundongos , Oligopeptídeos , Ratos , Ratos Wistar
9.
Microsc Res Tech ; 65(6): 276-81, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15662625

RESUMO

Severe cases of human envenoming by caterpillars of the saturniid moth Lonomia obliqua in Brazil can result in renal damage, leading to renal failure, and intracerebral hemorrhaging. In this work, we used immunohistochemical staining with rabbit antiserum raised against L. obliqua venom to examine venom distribution in selected tissues of the brain (cerebellum and hippocampus), kidneys, and liver of male Wistar rats injected with a single dose of venom (200 microg/kg, i.v.) and sacrificed 6, 18, 24, and 72 hours later. The immunolabeling of GFAP was also examined to assess the venom effects on perivascular astrocytic end-feet in the microvasculature of the hippocampus and cerebellum. Venom was detected in the kidneys (6 and 18 hours) and in the liver (6 hours) but not in the brain at any of the time intervals examined. In contrast, immunolabeling for GFAP revealed astrogliosis in the cerebellum and enhanced expression of this protein in the glial processes of the cerebellum and hippocampus, with a maximum response from 24 hours onwards. The high immunoreactivity seen in the kidneys agreed with the renal damage and dysfunction reported for some patients. The lack of venom detection in the brain, despite the altered expression of GFAP in astrocytes, suggested either that the venom does not enter this organ or that its entrance is transient and fast. Alternatively, the circulating venom may induce the release of mediators that could serve as second messengers to provoke the late astrocytic reactivity and astrogliosis. It is possible that both of these mechanisms may contribute to the effects observed.


Assuntos
Venenos de Artrópodes/farmacocinética , Mariposas/patogenicidade , Animais , Venenos de Artrópodes/análise , Venenos de Artrópodes/intoxicação , Barreira Hematoencefálica , Encéfalo/metabolismo , Proteína Glial Fibrilar Ácida/análise , Imuno-Histoquímica , Rim/metabolismo , Masculino , Ratos , Ratos Wistar , Distribuição Tecidual
10.
Toxicon ; 33(5): 659-65, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7660370

RESUMO

Two polypeptides from the venom of Polybia scutellaris were purified to homogeneity by RP-HPLC. They differ very slightly in mol. wt (both are about 23,000) and hydrophobicity, and have isoelectric points greater than 9. Amino acid analyzes show close similarity between them and with antigen 5 of vespids from different species. The two polypeptides have an identical N-terminal sequence (18 amino acids) which shows a high degree of homology with those of other vespids. Owing to the fact that the venom of this species is non-allergenic, the data for the mol. wt, isoelectric point, amino acid composition and N-terminal sequence allow us to identify the isolated polypeptides as two forms of antigen 5. Amino acids at positions 5 and 11 in P. scutellaris antigen 5 differ from those of the previously known sequences for antigen 5, suggesting that one or other might be responsible for the lack of allergenicity of the P. scutellaris venom.


Assuntos
Antígenos/análise , Antígenos/isolamento & purificação , Venenos de Artrópodes/química , Venenos de Artrópodes/isolamento & purificação , Alérgenos/isolamento & purificação , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Venenos de Artrópodes/análise , Dados de Sequência Molecular
11.
FEBS Lett ; 263(2): 251-3, 1990 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-2335228

RESUMO

A lethal neurotoxic polypeptide of Mr 8 kDa was purified from the venom of the South American 'armed' or wandering spider Phoneutria nigriventer by centrifugation, gel filtration on Superose 12, and reverse phase FPLC on columns of Pharmacia PepRPC and ProRPC. The purified neurotoxin Tx1 had an LD50 of 0.05 mg/kg in mice following intracerebroventricular injection. The complete amino acid sequence of the neurotoxin was determined by automated Edman degradation of the native and S-carboxymethylated protein in pulsed liquid and dual phase sequencers, and by the manual DABITC/PITC double coupling method applied to fragments obtained after digestions with the S. aureus V8 protease and trypsin. The neurotoxin Tx1 consists of a single chain of 77 amino acid residues, which contains a high proportion of cysteine. The primary structure showed no homology to other identified spider toxins.


Assuntos
Venenos de Artrópodes/análise , Neuropeptídeos/isolamento & purificação , Neurotoxinas/isolamento & purificação , Venenos de Aranha/análise , Sequência de Aminoácidos , Animais , Brasil , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Feminino , Masculino , Camundongos , Dados de Sequência Molecular , Neuropeptídeos/toxicidade
12.
Rev Biol Trop ; 36(2A): 241-6, 1988 Nov.
Artigo em Espanhol | MEDLINE | ID: mdl-3238077

RESUMO

A comparison of some components of the venoms of two Costa Rican tarantulas, Aphonopelma seemanni (Cambridge) and Sphaerobothria hoffmanni (Karsch) by polyacrylamide gel electrophoresis shows patterns similar to those of Dugesiella hentzi (Girard), a North American tarantula. The digestive secretions have proteins that do not enter the 15% gels; thus no bands are observed. The method used by the tarantulas to consume their prey involves the action of both the venom and the digestive secretions. The percent protein, pH, proteolytic activity and hemolytic activity of venom and digestive secretions of both species were determined, and a high proteolytic activity for digestive secretions was found.


Assuntos
Venenos de Artrópodes/análise , Secreções Intestinais/análise , Venenos de Aranha/análise , Animais , Eletroforese em Gel de Poliacrilamida , Feminino , Secreções Intestinais/fisiologia , Venenos de Aranha/fisiologia
13.
Rev. biol. trop ; Rev. biol. trop;36(2A): 241-6, nov. 1988. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-103737

RESUMO

A comparison of some components of the venoms of two Costa Rican tarantulas, Aphonopelma seeamanni (Cambridge) and Sphaerobothria hoffmanni (Karsch) by polyacrylamide gel electrophoresis shows patterns similar to those of Dugesiella hentzi (Girard), a North American tarantula. The digestive secretions have proteins that do not enter the 15% gels; thus no bands are obsorved. The method used by the tarantulas to consume their prey involves the action of both the venom and the digestive secretions. The percent protein, pH, proteolytic activity and hemolytic activity of venom and digestive secretions of both species were determined, and a high proteolytic activity for digestive secretions was found.


Assuntos
Feminino , Animais , Venenos de Artrópodes/análise , Secreções Intestinais/análise , Venenos de Aranha/análise , Eletroforese em Gel de Poliacrilamida , Secreções Intestinais/fisiologia , Venenos de Aranha/fisiologia
14.
Diagnóstico (Perú) ; 17(2): 39-45, feb. 1986. ilus, tab
Artigo em Espanhol | LILACS, LIPECS | ID: lil-54422

RESUMO

El veneno de arañas adultas Loxósceles laeta fue obtenido mediante electroestimulación y disección glandular. La distribución electroforética de las proteínas del veneno fue obtenida en gel de poliacrilamida a pH 8.6, obteniéndose 19 y 22 bandas proteicas respectivamente. Mediante electroforesis a pH 7.2 en presencia de dodecil sulfato de sodio de sodio se observaron tan solo 18 y 20 respectivamente. Las muestras estudiadas no producen coagulación del fibrinógeno humano, bovino ni plasma humano citratado. El veneno loxoscélico no hidrolizá los substratos BAPna, TAME ni Chromozym TH lo que demuestra la ausencia de Enzima similar a trombina. La presencia de acción procoagulante in vitro del veneno fue demostrada por la aceleración del tiempo de recalcificación del plasma humano. Se discute el rol de esta actividad en el envenenamiento loxoscélico


Assuntos
História do Século XX , Picada de Aranha/complicações , Eletroforese em Gel de Poliacrilamida , Aranhas/classificação , Venenos de Artrópodes/isolamento & purificação , Venenos de Artrópodes/análise , Peru
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