PURPOSE: To evaluate the effect of bioflavonoid ternatin (TRT) on rat liver regeneration and oxidative stress after 70% partial hepatectomy (PH). METHODS: Thirty six young male Wistar rats were randomly assigned to two groups of 18 animals each - control (G1) and experimental (G2) - and were submitted to PH under inhalatory diethylether anesthesia. G1 rats received daily intraperitoneal (ip) injections of saline (NaCl 0.9% solution) 0.1 mL/kg for 14 days; G2 animals received daily ip injections of TRT 0.1% 1.0mg/kg for 14 days. At 36h (T1), 168h (T2) and 336h (T3) post-PH timepoints, a subgroup of six rats in each group was chosen in a randomized way to complementary hepatectomy (CH) and blood samples haversting. Collected material was saved for laboratory analysis (total bilirubin (TB), D-Glucose, glutathione (GSH) and thiobarbituric acid reactive substances (TBARS) and assessment of liver regeneration. RESULTS: TRT induced a significant decrease in liver and plasma GSH concentrations; liver regeneration process was not affected. TRT promoted a significant decrease in blood glucose levels 168h after partial hepatectomy compared with controls. TB levels remained unchanged. CONCLUSION: Intraperitoneal bioflavonoid ternatin injection in partially hepatectomized rats induces a decrease in oxidative stress and a significant hypoglycemic state, but does not promote any change in the evolution of liver regeneration.

OBJETIVO: Estudar os efeitos dos ácidos graxos poli-insaturados (PUFA) ômega-3 e ômega-6 no estresse oxidativo e na regeneração hepática em ratos submetidos à hepatectomia parcial à 70% (HP, hepatectomia a 70%, hepatectomia parcial à Higgins-Anderson). MÉTODOS: 72 ratos Wistar machos jovens foram aleatoriamente distribuídos em quatro grupos de mesmo tamanho: controle, parcialmente hepatectomizados, e parcialmente hepatectomizados com aporte diário intraperitoneal, por duas semanas, de ou ômega-3 ou ômega-6. Nos tempos 36h (T1), 168h (T2) e 336h (T3) pós-HP, substâncias reativas ao ácido tiobarbitúrico (TBARS) e glutationa reduzida (GSH) foram medidos no plasma e no tecido hepático, enquanto glicose e bilirrubina total foram aquilatados no sangue. A massa do fígado residual, nos mesmos tempos, foi o parâmetro utilizado para estimar a evolução da regeneração hepática. RESULTADOS: PUFA ômega-3 inibiu a regeneração hepática e induziu redução na concentração de GSH hepático sete dias pós-HP. PUFA ômega-6, ao contrário, não mostrou efeito inibitório sobre a regeneração. Houve aumento da peroxidação lipídica tanto no sangue como no fígado com a administração de ômega-6. CONCLUSÃO: PUFA ômega-3 retardou a regeneração hepática pós-HP provavelmente por inibição do estresse oxidativo. PUFA ômega-6 aumentou as concentrações de TBARS no sangue e no fígado mas não alterou a evolução do processo regenerativo hepático.

OBJECTIVE: To study the effects of polyunsaturated fatty acids (PUFA) omega-3 and omega-6 in the oxidative stress and in liver regeneration in rats subjected to 70% partial hepatectomy (PH, 70% hepatectomy, Higgins- Anderson partial hepatectomy). METHODS: 72 young male Wistar rats were randomly divided into four equal-sized groups: control (G1), partially hepatectomized (G2), partially hepatectomized with two weeks daily intraperitoneal infusion of omega-3 (G3) and partially hepatectomized with two weeks daily intraperitoneal infuison of omega-6 (G4). In moments 36h (T1), 168h (T2) and 336h (T3) post-PH, thiobarbituric acid reactive substances (TBARS) and reduced glutathione (GSH) were measured in plasma and liver tissue, while glucose and total bilirubin were measured in blood. The mass of the residual liver in the same moments was the parameter used to estimate the evolution of liver regeneration. RESULTS: omega-3 PUFA inhibited liver regeneration and induced reduction of hepatic GSH concentration seven days post-PH. Omega-6 PUFA, in contrast, showed no inhibitory effect on regeneration. There was an increase of lipid peroxidation both in blood and liver with administration of omega-6. CONCLUSION: Omega-3 PUFA retarded post-PH liver regeneration, probably through inhibition of oxidative stress. Omega-6 PUFA increased TBARS concentrations in blood and liver but did not alter the evolution of the liver regenerative process.

OBJETIVO: Investigar o estresse oxidativo durante a regeneração hepática em ratos submetidos à hepatectomia (HP) e, ao mesmo tempo, avaliar a função hepática enquanto em regeneração. MÉTODO: 36 ratos Wistar machos jovens foram aleatoriamente distribuídos em dois grupos de 18 animais: submetidos somente à laparotomia (controle, Grupo G1) e parcialmente hepatectomizados (experimento, Grupo G2). Nos tempos 36h (T1), 168h (T2) e 336h (T3) pós-HP, GSH foi medida no plasma e no tecido hepático, enquanto Gli e BT foram aquilatados no sangue. A massa do fígado residual foi utilizada para estimar a evolução da regeneração hepática. RESULTADOS: Houve diferença estatisticamente significativa no crescimento dos lobos residuais nos grupos controle e experimento. GSH hepático e plasmático se mostraram significantemente maior nos animais parcialmente hepatectomizados.,em todos os tempos. Hiperglicemia estatisticamente significativa ocorreu nos ratos pós-HP nos tempos T2 e T3. A BT não apresentou qualquer alteração entre os grupos. CONCLUSÃO: Durante a regeneração hepática pós-HP em ratos há um aumento do estresse oxidativo e o fígado residual permanece apto na manutenção da homeostase orgânica.

BACKGROUND: The purpose of this study was to evaluate the oxidative stress and the hepatic function on rat liver regeneration after partial hepatectomy (PH). METHODS: Thirty-six young male Wistar rats were randomly assigned in two groups of 18 animals each: control group 1 (G1) the animals were only laparotomized, and group 2 (G2) rats were submitted to PH. In each group, at 36 hours (T1), 168 hours (T2) and 336 hours (T3) post-PH, a subgroup of 6 rats was chosen in a randomized way to be submitted to a total hepatectomy (TH) in G1, and to complete the hepatectomy (CH) in G2 rats. We measured blood samples and the residual liver lobes for reduced glutathione (GSH) (blood plasma and liver), blood concentrations of glucose (Glu), and total bilirubin (TB). All surgical procedures were performed under inhalator ether anesthesia. RESULTS: There was no significant difference on the liver regeneration between the 2 groups. Liver and blood GSH concentrations from G2 were significantly higher than G1. Significant hyperglycemia occurred at T2 and T3 in G2. TB measurements did not show any significant difference on both groups. CONCLUSION: There is an increased oxidative stress in rats on liver regeneration post-PH, but the residual liver lobes did not compromise with the organic homeostasis.

OBJETIVO: avaliar a influência do DMSO sobre o estresse oxidativo e a regeneração hepática pós-HP via um modelo experimental. MÉTODO: 36 ratos Wistar machos jovens foram aleatoriamente distribuídos em dois Grupos de 18 animais: parcialmente hepatectomizados com infusão diária de solução salina (controle) e parcialmente hepatectomizados com aporte diário intraperitoneal de DMSO, todos por duas semanas. Nos tempos 36h (T1), 168h (T2) e 336h (T3) pós-HP, glutationa (GSH) foi medida no plasma e no tecido hepático, enquanto glicose e bilirrubina total foram aquilatados no sangue. A massa do fígado residual, nos mesmos tempos, foi o parâmetro utilizado para estimar a evolução da regeneração do fígado. RESULTADOS: DMSO baixou os níveis de GSH hepático e sangüíneo mas não interferiu na evolução da massa em regeneração. CONCLUSÃO: DMSO inibiu o estresse oxidativo pós-HP mas não mostrou alterações significantes na regeneração hepática em ratos.

BACKGROUND: The purposes of this study were to evaluate dimethylsulfoxide (DMSO) influences on oxidative stress and rat liver regeneration after partial hepatectomy (PH). METHODS: 36 young male Wistar rats were randomly assigned to two groups of 18 animals each - experimental (G2) and control (G1) - and all of them were submitted to PH at the time T0. The G1 rats received daily for 14 days, by intraperitoneal (i.p.) route, NaCl 0.9% (saline) 0.1mL/kg and the G2 animals got daily DMSO 3% 0.1mL/kg by the same route. In each group, at 36h(T1), 168h(T2) and 336h(T3) post-PH, a subgroup of 6 rats were chosen in a randomized way to complementary hepatectomy, when blood and the residual liver lobes were taken to measure reduced glutathione (GSH) (blood plasma and liver) and blood concentrations of glucose and total bilirubin. All surgical procedures were performed under inhaled ether anesthesia. RESULTS: DMSO inhibited the liver and the plasma GSH concentrations after 7 days but did not show any significant effect on liver regeneration phenomenona. CONCLUSION: DMSO administration leads to an inhibitory effect on oxidative stress but did not show any change on the liver regeneration evolution in rats after PH.