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1.
J Pharmacol Toxicol Methods ; 64(2): 173-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21821138

RESUMO

Proper treatment of jellyfish envenomed patients can be successfully achieved only from an understanding of the overall functional changes and alterations in physiological parameters under its envenomation. The majority of previous investigations on jellyfish venoms have covered only a couple of parameters at a time. Unlike most other fragmentary jellyfish studies, we employed an integrative toxicological approach, including hemodynamics, clinical chemistry and hematology analyses, using N. nomurai jellyfish venom (NnV) in dogs. After the baseline measurements for mean arterial pressure (MAP), cardiac output (CO) and heart rate (HR), NnV was intravenously administered to the dogs at doses of 0.1 or 0.3mg/kg body weight. The dogs showed significant decreases in MAP (-27.4±3.7 and -48.1±9.9 mmHg), CO (-1.1±0.1 L/min and -1.0±0.2 L/min), and HR (-4.5±0.3 and -9.9±3.1 beats/min) comparing with the respective baseline controls. The onset of systemic hypotension and bradycardia occurred within 1 min of NnV injection and they lasted for 1-35 min, depending on the NnV doses. Interestingly, serum biochemical analyses of envenomed dogs exhibited dramatic increases of alkaline phosphatase (ALP), creatine phosphokinase (CPK), alanine aminotransferase (ALT) and aspartate aminotransferase (AST), indicating its possible target organs. In conclusion, we have demonstrated simultaneously, for the first time, the multiple organ toxicities (cardiotoxic, myotoxic and hepatotoxic) of a scyphozoan jellyfish venom. Based on these results, an integrative toxinological approach using dogs appears to be effective in predicting jellyfish venom toxicities and designing their therapeutic strategies. We expect this method can be applied to other jellyfish venom research as well.


Assuntos
Bradicardia/etiologia , Venenos de Cnidários/toxicidade , Hipotensão/etiologia , Cifozoários , Animais , Pressão Sanguínea/efeitos dos fármacos , Débito Cardíaco/efeitos dos fármacos , Venenos de Cnidários/administração & dosagem , Cães , Relação Dose-Resposta a Droga , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/patologia
2.
Toxicon ; 56(4): 521-5, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20493200

RESUMO

Hemiscorpius lepturus envenomation exhibits various pathological changes in the affected tissues, including skin, blood cells, cardiovascular and central nervous systems. The enzymatic activity and protein component of the venom have not been described previously. In the present study, the electrophoretic profile of H. lepturus venom was determined by SDS-PAGE (12 and 15%), resulting in major protein bands at 3.5-5, 30-35 and 50-60 kDa. The enzymatic activities of the venom was, for the first time, investigated using various zymography techniques, which showed the gelatinolytic, caseinolytic, and hyaluronidase activities mainly at around 50-60 kDa, 30-40 kDa, and 40-50 kDa, respectively. Among these, the proteolytic activities was almost completely disappeared in the presence of a matrix metalloproteinase inhibitor, 1, 10-phenanthroline. Antigen-antibody interactions between the venom and its Iranian antivenin was observed by Western blotting, and it showed several antigenic proteins in the range of 30-160 kDa. This strong antigen-antibody reaction was also demonstrated through an enzyme-linked immunosorbent assay (ELISA). The gelatinase activity of the venom was suppressed by Razi institute polyvalent antivenin, suggesting the inhibitory effect of the antivenin against H. lepturus venom protease activities. Prudently, more extensive clinical studies are necessary for validation of its use in envenomed patients.


Assuntos
Antivenenos/química , Inibidores Enzimáticos/química , Venenos de Escorpião/enzimologia , Escorpiões/enzimologia , Animais , Antivenenos/farmacologia , Western Blotting , Caseínas/química , Bovinos , Galinhas , Eletroforese em Gel de Poliacrilamida , Inibidores Enzimáticos/farmacologia , Ensaio de Imunoadsorção Enzimática , Gelatina/química , Gelatinases/antagonistas & inibidores , Gelatinases/química , Gelatinases/isolamento & purificação , Ácido Hialurônico/química , Hialuronoglucosaminidase/química , Hialuronoglucosaminidase/isolamento & purificação , Metaloendopeptidases/química , Metaloendopeptidases/isolamento & purificação , Venenos de Escorpião/química , Venenos de Escorpião/farmacologia , Suínos
3.
Food Chem Toxicol ; 48(2): 509-16, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19913068

RESUMO

The antidiabetic therapeutic effect of Ecklonia cava, a brown alga, was investigated using streptozotocin-induced type 1 diabetes mellitus rats and C2C12 myoblasts. The methanol extract of E. cava (ECM), having a strong radical scavenging activity, significantly reduced plasma glucose level and increased insulin concentration in type 1 diabetes mellitus rats. Moreover, the elevation of plasma ALT in diabetic rats was dramatically restored near to normal range by the treatment of ECM, whereas AST level was not meaningfully altered in any group throughout the experiment. The characteristic indications of diabetes, such as polyphagia and polydipsia, were greatly improved by ECM treatment as well. The mechanism of action of ECM appears to be, at least partially, mediated by the activation of both AMP-activated protein kinase/ACC and PI-3 kinase/Akt signal pathways. Taken together, the present results suggest that E. cava has both in vivo and in vitro antidiabetic effects.


Assuntos
Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Phaeophyceae/química , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/metabolismo , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Diabetes Mellitus Experimental/metabolismo , Ativação Enzimática/efeitos dos fármacos , Flavonoides/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Hipoglicemiantes/química , Insulina/sangue , Masculino , Metanol/química , Camundongos , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Mioblastos Esqueléticos/citologia , Mioblastos Esqueléticos/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Fenóis/análise , Extratos Vegetais/química , Polifenóis , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
4.
J Med Food ; 12(4): 776-81, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19735176

RESUMO

Garlic has long been known for its wide array of therapeutic effects, including hypolipidemic, antihypertensive, antimicrobial, and possibly anticancer effects; conversely, some adverse effects of garlic, such as acute pain and neurogenic inflammation, have also been reported. However, information detailing the toxicological significance of garlic is scarce. In this study, the cytotoxicities of fresh garlic extract (FGE) and boiled garlic extract (BGE) and their underlying toxic mechanisms were investigated using INT-407 intestinal epithelial cells. A brief exposure (20 minutes) to FGE induced a concentration-dependent increase in cell death (37 +/- 2% at 300 microg/mL), but no cytotoxic effects were induced after exposure to BGE. For FGE, only the high-molecular-mass (>10-kDa) proteins were associated with cytotoxic effects. FGE-treated cells showed morphological changes such as increased cell rounding and fragmentation, suggesting programmed cell death (apoptosis). Apoptosis of FGE-treated cells was evaluated by observing the fragmented multinuclei stained with Hoechst 33342. From the cell cycle analysis, the increase in hypodiploidic cells and in the G2/M phase cell population suggested not only apoptosis but also cell cycle arrest of FGE-treated cells. Pretreatment with N-acetyl-l-cysteine almost completely prevented FGE-induced cell death, suggesting that reactive oxygen species (ROS) may play a key role in FGE-associated cytotoxicity. Consumption of fresh garlic may be linked to potential cytotoxicity of intestinal cells when ROS scavengers are not present.


Assuntos
Apoptose/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Alho/toxicidade , Intestino Delgado/efeitos dos fármacos , Extratos Vegetais/toxicidade , Proteínas/toxicidade , Acetilcisteína/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Culinária , Alho/química , Temperatura Alta , Humanos , Extratos Vegetais/química , Raízes de Plantas , Proteínas/isolamento & purificação , Espécies Reativas de Oxigênio
5.
Artigo em Inglês | MEDLINE | ID: mdl-19303056

RESUMO

The recent bloom of a giant jellyfish Nemopilema nomurai has caused a danger to sea bathers and fishery damages in the waters of China, Korea, and Japan. The present study investigated the cytotoxic and hemolytic activities of crude venom extract of N. nomurai using a number of in vitro assays. The jellyfish venom showed a much higher cytotoxic activity in H9C2 heart myoblast than in C2C12 skeletal myoblast (LC(50)=2 microg/mL vs. 12 microg/mL, respectively), suggesting its possible in vivo selective toxicity on cardiac tissue. This result is consistent with our previous finding that cardiovascular function is a target of the venom. In order to determine the stability of N. nomurai venom, its cytotoxicity was examined under the various temperature and pH conditions. The activity was relatively well retained at low environmental temperature (or=60 degrees C). In pH stability test, the venom has abruptly lost its activity at low pH environment (pH

Assuntos
Venenos de Cnidários/toxicidade , Citotoxinas/toxicidade , Hemólise/efeitos dos fármacos , Cifozoários , Animais , Gatos , Células Cultivadas , Venenos de Cnidários/isolamento & purificação , Citotoxinas/isolamento & purificação , Cães , Relação Dose-Resposta a Droga , Hemólise/fisiologia , Humanos , Mioblastos/efeitos dos fármacos , Mioblastos/fisiologia , Coelhos , Ratos
6.
Environ Toxicol Pharmacol ; 27(1): 90-5, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21783925

RESUMO

Mercury chloride (HgCl(2)) and 4-nonylphenol (NP) are widespread environmental and industrial pollutants that are known to have toxic effects as well as endocrine disrupting activities. Although the individual effects of HgCl(2) and NP in liver have been relatively well recognized, little is known about the interaction of NP and HgCl(2) during the induction of their toxicity. In the current study, we investigated the synergism between HgCl(2) and NP using HepG2 cells. Surprisingly, the concurrent treatment of HepG2 with HgCl(2) and NP induced a significant cytotoxicity at concentrations where neither of them have any cytotoxic effect when treated alone. The cytotoxicity of NP is enhanced in the presence of HgCl(2) (a shift from 74.9 to 47.4µM in LC(50)) and vice versa (a shift from 94.9 to 66.3µM in LC(50)). Estrogen receptor antagonists such as ICI 182,780 did not protect HepG2 cells from these cytotoxic insults. Whereas the intracellular level of reduced form glutathione (GSH) was considerably decreased upon the co-treatment with NP and HgCl(2). Furthermore, the synergistic cytotoxicity was significantly inhibited by 20-mM N-acetylcysteine (NAC). These results indicate that the mutual synergistic cytotoxicity of HgCl(2) and NP on HepG2 cell is not associated with estrogen receptor signaling but mediated by reactive oxygen species (ROS) generation. In our real life, we are continuously and often simultaneously exposed to many different kinds of environmental pollutants. The present study suggests a mechanism of potential synergistic adverse effects of these toxic pollutants.

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