Total hepatic warm ischemia and reperfusion associated with controlled hemorrhagic shock: effects of neutrophil sequestration in rat liver

BACKGROUND:The purpose of this experimental study was to evaluate the effects of total hepatic ischemia and reperfusion on the accumulation of neutrophils in the liver of rats, under normal conditions and in rats submitted to controlled hemorrhagic shock . METHODS: Thirty two adult male Wistar rats, were divided into four groups: the Control group, was submitted to the standard procedures for a period of 60 min of observation; Shock group, was submitted to controlled hemorrhagic shock (mean arterial blood pressure = 40 mmHg, 20 min) followed by volume resuscitation (lactated Ringer's solution + blood, 3:1) and reperfusion for 60 min; Pringle group, was submitted to total hepatic ischemia for 15 min and reperfusion for 60 min; The Total group, was submitted to controlled hemorrhagic shock for 15 min followed by volume resuscitation (lactated Ringer's solution + blood, 3:1), total hepatic ischemia for 15 min and reperfusion for 60 min. Measurements of serum lactate and base excess were used to characterize the hemorrhagic shock state with low tissue perfusion. The counting of neutrophils on the liver tissue was performed after the euthanasia of animals. RESULTS: Values for the counting of neutrophils on the liver indicate that, the animals from Pringle group differed from Shock and Total groups (Control 10.30±3.20, Shock 13.94±2.84, Pringle 7.00±3.40, Total 12.45±3.65) but did not differ from Control group. CONCLUSIONS: Rats submitted to controlled hemorrhagic shock state associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not present significant neutrophils accumulation on liver tissue.O propósito deste trabalho experimental foi estudar os efeitos da isquemia e reperfusão hepática total sobre o acúmulo de neutrófilos no fígado de ratos, em condições de normalidade e submetidos ao estado de choque hemorrágico controlado. MÉTODO: Trinta e dois ratos Wistar, machos, foram divididos em quatro grupos de oito animais cada: grupo Controle, submetido à laparotomia com um período de 60 minutos de observação; grupo Choque, submetido a choque hemorrágico controlado (PAM = 40 mmHg, 20 min.) seguido de reposição volêmica (Ringer lactato + sangue, 3:1) e reperfusão (60 min.); grupo Pringle, submetido a isquemia hepática total (15 min.) e reperfusão (60 min.); grupo Total submetido a choque hemorrágico controlado (15 min.) seguido de reposição volêmica (Ringer lactato + sangue, 3:1) mais isquemia hepática total (15 min.) e reperfusão (60 min.). A dosagem do lactato arterial e déficit de base foram utilizados para caracterizar o estado de choque hemorrágico com baixa perfusão tecidual. Após a morte dos animais, procedeu-se à contagem de neutrófilos no tecido hepático. RESULTADOS: Na contagem de neutrófilos no fígado o grupo Pringle diferiu dos grupos Choque e Total, os quais não diferiram entre si (Controle 10,30±3,20; Choque 13,94±2,84; Pringle 7,00±3,40; Total 12,45±3,65). CONCLUSÃO: Em ratos submetidos a estado de choque hemorrágico controlado, associado à isquemia hepática total de 15 minutos, seguido de 60 minutos de reperfusão, não ocorreu acúmulo significativo de neutrófilos no fígado304275281The purpose of this experimental study was to evaluate the effects of total hepatic ischemia and reperfusion on the accumulation of neutrophils in the liver of rats, under normal conditions and in rats submitted to controlled hemorrhagic shock . METHODS: Thirty two adult male Wistar rats, were divided into four groups: the Control group, was submitted to the standard procedures for a period of 60 min of observation; Shock group, was submitted to controlled hemorrhagic shock (mean arterial blood pressure = 40 mmHg, 20 min) followed by volume resuscitation (lactated Ringer's solution + blood, 3:1) and reperfusion for 60 min; Pringle group, was submitted to total hepatic ischemia for 15 min and reperfusion for 60 min; The Total group, was submitted to controlled hemorrhagic shock for 15 min followed by volume resuscitation (lactated Ringer's solution + blood, 3:1), total hepatic ischemia for 15 min and reperfusion for 60 min. Measurements of serum lactate and base excess were used to characterize the hemorrhagic shock state with low tissue perfusion. The counting of neutrophils on the liver tissue was performed after the euthanasia of animals. RESULTS: Values for the counting of neutrophils on the liver indicate that, the animals from Pringle group differed from Shock and Total groups (Control 10.30±3.20, Shock 13.94±2.84, Pringle 7.00±3.40, Total 12.45±3.65) but did not differ from Control group. CONCLUSIONS: Rats submitted to controlled hemorrhagic shock state associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not present significant neutrophils accumulation on liver tissu

Recrutamento de neutrófilos através da barreira hematoencefálica: importância da isquemia hepática pós-traumática

PURPOSE: To study the effects of total hepatic ischemia, and reperfusion on the accumulation of neutrophils in the brain of rats submitted to normovolemic conditions as well as to controlled hemorrhagic shock state. METHODS: Thirty two adult male Wistar rats, were divided into four groups: the Control group, was submitted to the standard procedures for a period of 60 min of observation; Shock group, was submitted to controlled hemorrhagic shock (mean arterial blood pressure=40mmHg, 20min) followed by volemic resuscitation (lactated Ringer's solution + blood, 3:1) and reperfusion for 60min; Pringle group, was submitted to total hepatic ischemia for 15min and reperfusion for 60min. The total group was submitted to controlled hemorrhagic shock for 20min followed by volemic resuscitation (lactated Ringer's solution + blood, 3:1), total hepatic ischemia for 15min and reperfusion for 60min. Measurements of serum lactate and base excess were used to characterize the hemorrhagic shock state with low tissue perfusion. The counting of neutrophils on the brain was performed after the euthanasia of animals. RESULTS: The values for the counting of neutrophils on the brain indicate that did not occur difference among studied groups (p=0.196) (Control 0.12± 0.11, Shock 0.12± 0.13, Pringle 0.02± 0.04, Total 0.14± 0.16). CONCLUSION: Hemorrhagic shock associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not causes significant neutrophils accumulation in the brain of rats.Estudar o efeito da isquemia e reperfusão hepática total sobre acúmulo de neutrófilos no cérebro de ratos, em condições de normalidade e submetidos ao estado de choque hemorrágico controlado. MÉTODOS: Foram utilizados 32 ratos Wistar, machos, distribuídos em quatro grupos de oito animais cada: Grupo Controle, submetido aos procedimentos padrões com um período de 60 minutos de observação; Grupo Choque, submetido a choque hemorrágico controlado (PAM=40mmHg, 20 min) seguido de reposição volêmica (Ringer lactato + sangue, 3:1) e reperfusão (60 min); Grupo Pringle, submetido à isquemia hepática total (15 min) e reperfusão (60 min); Grupo Total submetido a choque hemorrágico controlado (15 min) seguido de reposição volêmica (Ringer lactato + sangue, 3:1) mais isquemia hepática total (15 min) e reperfusão (60 min). A dosagem do lactato arterial e déficit de base foram utilizados para caracterizar o estado de choque hemorrágico com baixa perfusão tecidual. Após a eutanásia dos animais, procedeu-se à contagem de neutrófilos no cérebro. RESULTADOS: a contagem de neutrófilos mostrou que não houve diferença estatística entre os grupos (p=0.196). Grupo Controle 0.12± 0.11, Choque 0.12± 0.13, Pringle 0.02± 0.04 e Total 0.14± 0.16. CONCLUSÃO: Em ratos submetidos a estado de choque hemorrágico controlado associado à isquemia hepática total de 15 minutos, seguido de 60 minutos de reperfusão, não ocorreu acúmulo significativo de neutrófilos no cérebro185392397To study the effects of total hepatic ischemia, and reperfusion on the accumulation of neutrophils in the brain of rats submitted to normovolemic conditions as well as to controlled hemorrhagic shock state. METHODS: Thirty two adult male Wistar rats, were divided into four groups: the Control group, was submitted to the standard procedures for a period of 60 min of observation; Shock group, was submitted to controlled hemorrhagic shock (mean arterial blood pressure=40mmHg, 20min) followed by volemic resuscitation (lactated Ringer's solution + blood, 3:1) and reperfusion for 60min; Pringle group, was submitted to total hepatic ischemia for 15min and reperfusion for 60min. The total group was submitted to controlled hemorrhagic shock for 20min followed by volemic resuscitation (lactated Ringer's solution + blood, 3:1), total hepatic ischemia for 15min and reperfusion for 60min. Measurements of serum lactate and base excess were used to characterize the hemorrhagic shock state with low tissue perfusion. The counting of neutrophils on the brain was performed after the euthanasia of animals. RESULTS: The values for the counting of neutrophils on the brain indicate that did not occur difference among studied groups (p=0.196) (Control 0.12± 0.11, Shock 0.12± 0.13, Pringle 0.02± 0.04, Total 0.14± 0.16). CONCLUSION: Hemorrhagic shock associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not causes significant neutrophils accumulation in the brain of rats

Modelo experimental de carcinoma mamário em ratas induzidas com 7,12-dimetilbenz(a)antraceno.

Objective: To test an experimental model of chemical mammary carcinogenesis induction in SpragueDawley rats. Methods: Thirty virgin Sprague-Dawley female rats, aged 50 days, received 20 mg of 7,12-dimethylbenz(a)anthracene (DMBA) intragastrically by gavage. At 12 week their mammary glands were examined. Brain, liver, bone and lung tissue were also analyzed. Results: Twelve weeks after DMBA injection, 85% rats presented at least one breast tumor. Conclusin: This experimental animal model of chemical mammary induced carcinogenesis is feasible and can be used in further experiments on the role of tumorigenic biomodulator substances.Objetivo: Testar um modelo experimental de indução de carcinogênese em ratas Sprague-Dawley. Métodos: Foram estudadas 30 ratas fêmeas virgens Sprague-Dawley, induzidas ao carcinogênese mamário. Com 50 dias de vida, foi injetado 7,12-dimetilbenz(a)antrace no ventre por gavage. Com 12 semanas, as glândulas mamárias foram examinadas, assim como os tecidos cerebrais, pulmonares, ossos do fêmur e fígado. Resultados: Doze semanas após a injeção de DMBA, 85% das ratas apresentaram pelo menos um tumor mamário visível. Conclusão: O modelo experimental de carcinoma mamário induzido por DMBA mostrou-se efetivo e de fácil reprodução

Total hepatic warm ischemia and reperfusion associated with controlled hemorrhagic shock: effects of neutrophil sequestration in lung of rats

CNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOOBJECTIVE: The purpose of this experimental work was to study the effects of total hepatic ischemia and reperfusion on the accumulation of neutrophils in the lung of rats, under normal conditions and submitted to controlled hemorrhagic shock state. METHODS: thirty two adult male Wistar rats, were divided into four groups: the Sham group, was submitted to the standard procedures for a period of 60 min. of observation; Shock group, was submitted to controlled hemorrhagic shock (PAM=40 mmHg, 20 min.) followed by volemic resuscitation (lactated Ringer?s solution + blood, 3:1) and reperfusão for 60 min.; Pringle group, was submitted to total hepatic ischemia for 15 min. and reperfusão for 60 min.; The Total group, was submitted to controlled hemorrhagic shock for 15 min. followed by volemic resuscitation (lactated Ringer?s solution + blood, 3:1) and reperfusão for 60 min.). The counting of neutrophils on the lung tissue was performed after the euthanasia of animals. RESULTS: The values found for the counting of neutrophils on the lung tissue indicate that the animals from the Pringle, Total, and Shock groups, did not differ from the Sham group, having the following values: Sham, 21,08± 14,12; Shock, 35,15± 18,74; Pringle, 19,78± 15,38; Total, 23,90± 16,37) (p=0.253). CONCLUSION: Rats submitted to controlled hemorrhagic shock state associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not present significant neutrophils accumulation on the lung tissue.Estudar os efeitos da isquemia e reperfusão hepática total sobre acúmulo de neutrófilos no interstício pulmonar de ratos, em condições de normalidade e submetidos ao estado de choque hemorrágico controlado. MÉTODOS: 32 ratos Wistar, machos, foram divididos em quatro grupos de oito animais cada: grupo Sham, submetido aos procedimentos padrões com um período de 60 minutos de observação; grupo Choque, submetido a choque hemorrágico controlado (PAM = 40 mmHg, 20 min.) seguido de reposição volêmica (Ringer lactato + sangue, 3:1) e reperfusão (60 min.); grupo Pringle, submetido a isquemia hepática total (15 min.) e reperfusão (60 min.); grupo Total submetido a choque hemorrágico controlado (15 min.) seguido de reposição volêmica (Ringer lactato + sangue, 3:1) e reperfusão (60 min.). Após o sacrifício dos animais, procedeu-se à contagem de neutrófilos no interstício pulmonar. RESULTADOS: Os valores encontrados para contagem de neutrófilos no interstício pulmonar indicaram que, os animais dos grupos Pringle, Total e, também, do grupo Choque, não diferiram dos animais do grupo Sham com valores de (Sham 21,08± 14,12; Choque 35,15± 18,74; Pringle 19,78± 15,38; Total 23,90± 16,37) (p=0.253) CONCLUSÃO: Em ratos submetidos a estado de choque hemorrágico controlado associado a isquemia hepática de 15 minutos, seguida de 60 minutos de reperfusão, não ocorreu acúmulo significativo de neutrófilos no interstício pulmonar1714654CNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOCNPQ – CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOsem informaçãoThe purpose of this experimental work was to study the effects of total hepatic ischemia and reperfusion on the accumulation of neutrophils in the lung of rats, under normal conditions and submitted to controlled hemorrhagic shock state. METHODS: thirty two adult male Wistar rats, were divided into four groups: the Sham group, was submitted to the standard procedures for a period of 60 min. of observation; Shock group, was submitted to controlled hemorrhagic shock (PAM=40 mmHg, 20 min.) followed by volemic resuscitation (lactated Ringer?s solution + blood, 3:1) and reperfusão for 60 min.; Pringle group, was submitted to total hepatic ischemia for 15 min. and reperfusão for 60 min.; The Total group, was submitted to controlled hemorrhagic shock for 15 min. followed by volemic resuscitation (lactated Ringer?s solution + blood, 3:1) and reperfusão for 60 min.). The counting of neutrophils on the lung tissue was performed after the euthanasia of animals. RESULTS: The values found for the counting of neutrophils on the lung tissue indicate that the animals from the Pringle, Total, and Shock groups, did not differ from the Sham group, having the following values: Sham, 21,08± 14,12; Shock, 35,15± 18,74; Pringle, 19,78± 15,38; Total, 23,90± 16,37) (p=0.253). CONCLUSION: Rats submitted to controlled hemorrhagic shock state associated to total hepatic ischemia for 15 minutes, followed by 60 minutes of reperfusion, did not present significant neutrophils accumulation on the lung tissu

Decreased expression of stem cell markers by simvastatin in 7,12- dimethylbenz(a)anthracene (dmba)-induced breast cancer

FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORSimvastatin, a competitive inhibitor of HMG-CoA reductase widely used in the treatment and prevention of hyperlipidemia-related diseases, has recently been associated to in vitro anticancer stem cell (CSC) actions. However, these effects have not been confirmed in vivo. To assess in vivo anti-CSC effects of simvastatin, female Sprague-Dawley rats with 7,12-dimethyl-benz(a)anthracene (DMBA)-induced mammary cancer and control animals were treated for 14 days with either simvastatin (20 or 40 mg/kg/day) or soybean oil (N = 60). Tumors and normal breast tissues were removed for pathologic examination and immunodetection of CSC markers. At 40 mg/kg/day, simvastatin significantly reduced tumor growth and the expression of most CSC markers. The reduction in tumor growth (80%) could not be explained solely by the decrease in CSCs, since the latter accounted for less than 10% of the neoplasia (differentiated cancer cells were also affected). Stem cells in normal, nonneoplastic breast tissues were not affected by simvastatin. Simvastatin was also associated with a significant decrease in proliferative activity but no increase in cell death. In conclusion, this is the first study to confirm simvastatin anti-CSC actions in vivo, further demonstrating that this effect is specific for neoplastic cells, but not restricted to CSCs, and most likely due to inhibition of cell proliferation.Simvastatin, a competitive inhibitor of HMG-CoA reductase widely used in the treatment and prevention of hyperlipidemia-related diseases, has recently been associated to in vitro anticancer stem cell (CSC) actions. However, these effects have not been confirmed in vivo. To assess in vivo anti-CSC effects of simvastatin, female Sprague-Dawley rats with 7,12-dimethyl-benz(a)anthracene (DMBA)-induced mammary cancer and control animals were treated for 14 days with either simvastatin (20 or 40 mg/kg/day) or soybean oil (N = 60). Tumors and normal breast tissues were removed for pathologic examination and immunodetection of CSC markers. At 40 mg/kg/day, simvastatin significantly reduced tumor growth and the expression of most CSC markers. The reduction in tumor growth (80%) could not be explained solely by the decrease in CSCs, since the latter accounted for less than 10% of the neoplasia (differentiated cancer cells were also affected). Stem cells in normal, nonneoplastic breast tissues were not affected by simvastatin. Simvastatin was also associated with a significant decrease in proliferative activity but no increase in cell death. In conclusion, this is the first study to confirm simvastatin anti-CSC actions in vivo, further demonstrating that this effect is specific for neoplastic cells, but not restricted to CSCs, and most likely due to inhibition of cell proliferation433400410FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL E NÍVEL SUPERIORFAPESP [Fapesp]2010/10703-0sem informaçã