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1.
Toxicon ; 176: 59-66, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32057833

RESUMO

Rhopalurus junceus is the most common scorpion in Cuba and the venom is often used as a natural product for anti-cancer therapy. Despite this, no study has been published concerning its toxicological profile. The aim of the study was characterizing the short-term, subchronic toxicity and the teratogenic potential of Rhopalurus junceus scorpion venom by oral route in mice. Short-term oral toxicity was test in both sexes NMRI mice that received 100 mg/kg/day of scorpion venom extract for 28 days. For the subchronic study, mice were administered with three doses (0.1, 10, and 100 mg/kg) by oral route for 90 days. Teratogenic potential was tested in pregnant mice administered from day 6-15 post conception. Significant differences were observed in body weight and food intake of animal treated for short-term and subchronic assays. Variations in serum urea and cholesterol were observed after 90 days oral treatment. Spontaneous findings not related to the treatment were reveal in histology evaluation. Exposure in pregnant mice did not produce maternal toxicity. Signs of embryo-fetal toxicity were not observed. The current study provides evidence that exposure to low or moderate dose of Rhopalurus junceus scorpion venom by oral route did not affect health of animals and has low impact on reproductive physiology.


Assuntos
Venenos de Escorpião/toxicidade , Teratógenos/toxicidade , Testes de Toxicidade Subcrônica , Administração Oral , Animais , Cuba , Feminino , Masculino , Camundongos , Escorpiões , Teratogênese
2.
Int J Biol Macromol ; 72: 1343-50, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25450835

RESUMO

Chitosan is a natural polymer with excellent properties such as biocompatibility, biodegradability, non-toxicity and adsorptive abilities. We obtained chitosan derived from Panurilus argus lobster shell and its lactate and acetate salts to introduce in pharmaceutical industry. We examined the single and repeated dose toxicity of chitosan and its lactate and acetate salts. Single oral doses of 2000 mg/kg were well tolerated for all three materials. In the repeat dose tests, animals treated with chitosan only show a slight erythrocytes increase. Variations in erythrocyte and leukocyte count and some biochemical parameters were observed in animals treated with chitosan acid salts. One g/kg orally was found to be the subacute NOAEL for chitosan due to the hematological findings observed were not considered adverse. Chitosans obtained from Panurilus argus lobster shell have low toxicity and may be safe in rats because it did not cause any lethality or changes in the general behavior in both the single and repeated dose toxicity studies.


Assuntos
Quitosana/toxicidade , Decápodes/química , Sais/toxicidade , Administração Oral , Animais , Glicemia/análise , Peso Corporal/efeitos dos fármacos , Contagem de Células , Relação Dose-Resposta a Droga , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Feminino , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos Wistar , Testes de Toxicidade Aguda
3.
Exp Toxicol Pathol ; 65(1-2): 49-53, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21703836

RESUMO

The potential of oral exposure to calcium and magnesium citrate, a natural product obtained from dolomite, to initiate teratogenesis was analyzed in Wistar rats. Animals received calcium and magnesium citrate oral doses of 250, 500 and 1000 mg/kg during the period of gestation from day 6 to 17 post conception. Maternal, embryo and fetal toxicity was evaluated. Calcium and magnesium citrate exposure did not produce maternal toxicity assessed by clinical observations, body weight gain, food intake, hematology, biochemical parameters and necropsy finding. Signs of embryo-fetal toxicity were not observed. Skeletal and visceral malformations were seen occasionally in all drug-treated and control groups. Skeletal and visceral variations were similar in control and drug-treated groups except for incomplete ossification rib. These finding was spontaneous and unrelated to the drug. In conclusion, in this study we found that the oral exposure to rats of up to 1000 mg/kg of calcium and magnesium citrate during organogenesis did not induce significant maternal and embryo-fetal toxicity. The experimentally derived NOAEL for developmental toxicity was 1000 mg/kg.


Assuntos
Citrato de Cálcio/toxicidade , Ácido Cítrico/toxicidade , Exposição Materna/efeitos adversos , Organogênese/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Animais , Carbonato de Cálcio/química , Citrato de Cálcio/isolamento & purificação , Ácido Cítrico/isolamento & purificação , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Desenvolvimento Embrionário/efeitos dos fármacos , Determinação de Ponto Final , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Magnésio/química , Anormalidades Musculoesqueléticas/induzido quimicamente , Anormalidades Musculoesqueléticas/embriologia , Nível de Efeito Adverso não Observado , Compostos Organometálicos/isolamento & purificação , Gravidez , Ratos , Ratos Wistar , Costelas/anormalidades , Costelas/efeitos dos fármacos , Costelas/embriologia
4.
Curr Neurovasc Res ; 9(4): 233-8, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22962865

RESUMO

The objective of this investigation was to assess the toxicological potential of nasal formulation of erythropoietin with low sialic acid content (Neuro EPO) after 28 days of intra-nasal dosing in rats besides to evaluate the immunogenicity and erythropoietic effect of the test substance. Healthy Wistar rats of both sexes were used for 28 days subacute toxicity and immunogenicity assays. Doses evaluated were 3450, 4830 and 6900 UI/kg/day. The toxicological endpoints examined included animal body weight, food consumption, hematological and biochemical patterns, antibodies determination, selected tissue weights and histopathological examination. Reversibility of toxic effects was evaluated at high dose 14 days after treatment period. Female B6D2F1 mice were used for evaluated erythropoietic effect of the nasal formulation. Hematological endpoints were examined every week during 28 days of intra-nasal dosing of 6900 UI/kg/day. Variations of hematological patterns were not observed after 28 days of intranasal dosing. A slight increase in glucose level of treated animals within the normal range was observed. This effect was not dose related and was reversible. Antibody formation was not observed in any of the test doses. Histopathological examination of organs and tissues did not reveal treatment induced changes. The administration of Neuro EPO in normocythaemic mice did not produce erythropoietic effect. These results suggest that Neuro EPO could be used as a neuroprotective agent, without significant systemic haematological side effects.


Assuntos
Eritropoese/fisiologia , Eritropoetina/administração & dosagem , Ácido N-Acetilneuramínico/administração & dosagem , Testes de Toxicidade Aguda , Administração Intranasal , Animais , Esquema de Medicação , Eritropoese/efeitos dos fármacos , Eritropoetina/toxicidade , Feminino , Masculino , Camundongos , Ácido N-Acetilneuramínico/toxicidade , Ratos , Ratos Wistar , Testes de Toxicidade Aguda/métodos
5.
ALTEX ; 28(3): 227-35, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21993958

RESUMO

Disadvantages of the regulatory pyrogen test to assure safety of the end-product Human Serum Albumin (HSA) for parenteral use call for the implementation of an alternative test. In the current study, 16 HSA batches were assayed for pyrogens in parallel with the Rabbit Pyrogen Test, conventional and endotoxin-specific LAL assay and monocyte activation test (MAT). It was found that all HSA batches were contaminated with (1,3)-beta-glucans, which interfere with the conventional LAL. Endotoxin-specific LAL was not suitable to test HSA due to unacceptable endotoxin recovery. Experiments combining polymyxin B and MAT demonstrated that pyrogenic batches were mainly contaminated with endotoxins. However, endotoxin-specific LAL failed to detect one of them. The contaminating (1,3)-beta-glucans enhanced the MAT/IL-6 response to endotoxin, but not that of MAT/IL-1beta. The endotoxin equivalent concentrations obtained using the IL-6 readout were usually higher than those using IL-1beta, probably owing to the direct induction of IL-6 release from monocytes by (1,3)-beta-glucans. The MAT correlates with the rabbit pyrogen test, providing a higher safety level for pyrogenicity testing of HSA and probably other therapeutic proteins.


Assuntos
Endotoxinas/toxicidade , Monócitos/efeitos dos fármacos , Pirogênios/toxicidade , Albumina Sérica/química , Animais , Contaminação de Medicamentos , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Infusões Parenterais , Interleucina-1beta , Interleucina-6 , Teste do Limulus , Coelhos , Soluções
6.
Exp Toxicol Pathol ; 63(6): 563-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20488687

RESUMO

The use of human recombinant erythropoietin (EPO) as a neuroprotective agent is limited due to its hematological side effects. An erythropoietin along with a low content of sialic acid (rhEPOb), similar to that produced in the brain during hypoxia, may be used as a neuroprotective agent without risk of thrombotic events. The objective of this investigation was to assess the toxicological potential of a nasal formulation with rhEPOb in acute, subacute and nasal irritation assays in rats. Healthy Wistar rats (Cenp:Wistar) were used for the assays. In an irritation test, animals received 15 µl of rhEPOb into the right nostril. Rats were sacrificed after 24 h and slides of the nasal mucosa tissues were examined. Control and treated groups showed signs of a minimal irritation consisting of week edema and vascular congestion in all animals. In the acute toxicity test, the dose of 47,143 UI/kg was administered by nasal route. Hematological patterns, body weight, relative organ weight, and organ integrity were not affected by single dosing with rhEPOb. In the subacute toxicity test, Wistar rats of both sexes received 6,600 UI/kg/day for 14 days. The toxicological endpoints examined included animal body weight, food consumption, hematological and biochemical patterns, selected tissue weights, and histopathological examinations. An increase of lymphocytes was observed in males that was considered to reflect an immune response to treatment. Histopathological examination of organs and tissues did not reveal treatment-induced changes. The administration of rhEPOb at daily doses of 6,600 UI/kg during 14 days did not produce hematological side effects. These results suggest that rhEPOb could offer the same neuroprotection as EPO, without hematological side effects.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/sangue , Eritropoetina/toxicidade , Ácido N-Acetilneuramínico/análise , Mucosa Nasal/efeitos dos fármacos , Fármacos Neuroprotetores/toxicidade , Administração Intranasal , Animais , Relação Dose-Resposta a Droga , Eritropoetina/administração & dosagem , Eritropoetina/química , Feminino , Masculino , Mucosa Nasal/patologia , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/química , Ratos , Ratos Wistar , Testes de Toxicidade Aguda , Testes de Toxicidade Subaguda
7.
Exp Toxicol Pathol ; 63(4): 387-91, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20335011

RESUMO

We have studied the acute and subchronic oral toxicities of Calendula officinalis extract in male and female Wistar rats. A single acute C. officinalis extract dose of 2000 mg/kg dissolved in distilled water was administered by oral gavage for acute toxicity. Subchronic doses of 50, 250 and 1000 mg/kg/day were administered in drinking water. The major toxicological endpoints examined included animal body weight, water and food intake, selected tissue weights, and histopathological examinations. In addition, we examined blood elements: hematocrit, hemoglobin concentration, erythrocyte count, total and differential leukocyte count and blood clotting time and blood chemistry: glucose, total cholesterol, urea, total proteins, alkaline phosphatase, alanine aminotransferase (ALT) and aspartate aminotransferase (AST). In the acute study, there were no mortality and signs of toxicity. In the subchronic study, several of the blood elements were significantly affected in males and females after 90 days; hemoglobin, erythrocytes, leukocytes and blood clotting time. For blood chemistry parameters, ALT, AST and alkaline phosphatase were affected. Histopathological examination of tissues showed slight abnormalities in hepatic parenchyma that were consistent with biochemical variations observed. These studies indicate that the acute and subchronic toxicities of C. officinalis extract are low.


Assuntos
Calendula , Flores , Extratos Vegetais/toxicidade , Animais , Feminino , Masculino , Nível de Efeito Adverso não Observado , Ratos , Ratos Wistar
8.
Rev. cuba. plantas med ; 13(3)jul.-sept. 2008. ilus
Artigo em Espanhol | LILACS | ID: lil-506493

RESUMO

Fundamentación: los extractos de Momordica charantia L. poseen potencial terapéutico avalado científicamente que posibilita el empleo de esta planta en diversas enfermedades, sobre todo en la diabetes, por lo que caracterizar su potencial tóxico es de gran importancia para avalar el empleo de esta planta como agente terapéutico. Objetivos: realizar los estudios de toxicidad aguda oral e irritación ocular y dérmica a extractos acuoso e hidroalcohólico de M. charantia, con la finalidad de caracterizar su potencial toxicológico agudo. Métodos: el ensayo de toxicidad aguda oral se llevó a cabo en ratas Wistar hembras mediante el método de las clases tóxicas agudas, con la dosis máxima de 2 000 mg/kg. Los ensayos de irritación dérmica y ocular se llevaron a cabo en conejos Nueva Zelanda siguiendo los métodos descritos en las normas OECD 404 y 405. Resultados: la evaluación del extracto hidroalcohólico de M. charantia en el ensayo de toxicidad aguda mostró signos tóxicos por causa de la presencia de etanol en el extracto y una ligera disminución del peso corporal que no fue significativa. La administración del extracto acuoso no provocó signos tóxicos ni mortalidad. Ambos extractos se clasificaron en categoría 5 para ubicarse en el rango de toxicidad de una DL50> 2 000 mg/kg. En el ensayo de irritación dérmica y ocular se clasificaron los extractos como no irritantes. Conclusiones: los extractos evaluados mostraron un bajo potencial tóxico agudo tanto por vía oral como tópica.


Rationale: Momordica charantia L. extracts have scientifically-endorsed therapeutical potentialities that make the use of this plant possible in several diseases, mainly for diabetes, so characterizing its toxic potential is of great significance to support this plant as a therapeutical agent. Objectives: to conduct acute oral toxicity and ocular and dermal irritation studies on aqueous hydroalcoholic extracts from M. charantia, with the aim of characterizing its acute toxicological potential. Methods: Acute oral toxicity test was applied to female Wistar rats through acute toxic class method, with maximum dose of 2000 mg/kg. Ocular/dermal irritation tests were made in New Zealand rabbits, following the described methods in OECD standards 404 and 405. Results: the evaluation of M. charantia hydroalcoholic extract in the acute toxicity test showed toxic signs due to ethanol in the extract and a minimum bodyweight reduction that was not significant. The administration of water extract elicited neither toxic signs nor mortality. Both extracts were classified into category 5 within the range of toxicity of DL50> 2 000 mg/kg. The dermal/ocular irritation test indicated that the studied extracts were not irritating. Conclusions: The evaluated extracts showed low acute toxic potential for both oral and topical administration.


Assuntos
Animais , Momordica charantia/toxicidade , Plantas Medicinais , Testes de Irritação da Pele , Testes de Toxicidade Crônica
9.
Rev. cuba. plantas med ; 13(3)jul.-sep. 2008. ilus
Artigo em Espanhol | CUMED | ID: cum-37450

RESUMO

Fundamentación: los extractos de Momordica charantia L. poseen potencial terapéutico avalado científicamente que posibilita el empleo de esta planta en diversas enfermedades, sobre todo en la diabetes, por lo que caracterizar su potencial tóxico es de gran importancia para avalar el empleo de esta planta como agente terapéutico. Objetivos: realizar los estudios de toxicidad aguda oral e irritación ocular y dérmica a extractos acuoso e hidroalcohólico de M. charantia, con la finalidad de caracterizar su potencial toxicológico agudo. Métodos: el ensayo de toxicidad aguda oral se llevó a cabo en ratas Wistar hembras mediante el método de las clases tóxicas agudas, con la dosis máxima de 2 000 mg/kg. Los ensayos de irritación dérmica y ocular se llevaron a cabo en conejos Nueva Zelanda siguiendo los métodos descritos en las normas OECD 404 y 405. Resultados: la evaluación del extracto hidroalcohólico de M. charantia en el ensayo de toxicidad aguda mostró signos tóxicos por causa de la presencia de etanol en el extracto y una ligera disminución del peso corporal que no fue significativa. La administración del extracto acuoso no provocó signos tóxicos ni mortalidad. Ambos extractos se clasificaron en categoría 5 para ubicarse en el rango de toxicidad de una DL50> 2 000 mg/kg. En el ensayo de irritación dérmica y ocular se clasificaron los extractos como no irritantes. Conclusiones: los extractos evaluados mostraron un bajo potencial tóxico agudo tanto por vía oral como tópica(AU)


Rationale: Momordica charantia L. extracts have scientifically-endorsed therapeutical potentialities that make the use of this plant possible in several diseases, mainly for diabetes, so characterizing its toxic potential is of great significance to support this plant as a therapeutical agent. Objectives: to conduct acute oral toxicity and ocular and dermal irritation studies on aqueous hydroalcoholic extracts from M. charantia, with the aim of characterizing its acute toxicological potential. Methods: Acute oral toxicity test was applied to female Wistar rats through acute toxic class method, with maximum dose of 2000 mg/kg. Ocular/dermal irritation tests were made in New Zealand rabbits, following the described methods in OECD standards 404 and 405. Results: the evaluation of M. charantia hydroalcoholic extract in the acute toxicity test showed toxic signs due to ethanol in the extract and a minimum bodyweight reduction that was not significant. The administration of water extract elicited neither toxic signs nor mortality. Both extracts were classified into category 5 within the range of toxicity of DL50> 2 000 mg/kg. The dermal/ocular irritation test indicated that the studied extracts were not irritating. Conclusions: The evaluated extracts showed low acute toxic potential for both oral and topical administration(AU)


Assuntos
Animais , Momordica charantia/toxicidade , Plantas Medicinais , Testes de Toxicidade Crônica , Testes de Irritação da Pele
10.
Exp Toxicol Pathol ; 60(6): 499-504, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18579354

RESUMO

The potential of oral exposure to dolomite, a natural product that contains calcium and magnesium, to initiate teratogenesis was analyzed in Wistar rats. Animals received dolomite oral dosages of 500 and 1500mg/kg during the period of gestation from day 6-15 post conceptionem (p.c.). Maternal, embryo and fetal toxicity were evaluated. Dolomite exposure did not produce maternal toxicity assessed by clinical observations, body weight gain, hematology parameters and relative organs weight. Signs of embryo-fetal toxicity were not observed. Skeletal malformations and visceral variations were similar in control and dolomite-treated groups. On the other hand, slight increase was observed in fetal body weight in the dolomite-treated group. Treatment with dolomite resulted in significantly decreased incidences of unossified xiphisternum, incomplete ossification of xiphisternum and sternebrae. These effects could be caused by a beneficial influence of calcium and magnesium salts present in dolomite on ossification process. In conclusion, in this study we found that the oral exposure to rats of up to 1500mg/kg of dolomite during organogenesis did not induce significant maternal and embryo-fetal toxicity.


Assuntos
Carbonato de Cálcio/toxicidade , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Fetal/efeitos dos fármacos , Magnésio/toxicidade , Exposição Materna/efeitos adversos , Minerais/toxicidade , Organogênese/efeitos dos fármacos , Administração Oral , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/embriologia , Relação Dose-Resposta a Droga , Feminino , Peso Fetal/efeitos dos fármacos , Nível de Efeito Adverso não Observado , Osteogênese/efeitos dos fármacos , Gravidez , Ratos , Ratos Wistar
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