ABSTRACT
The aim of this study was to determine oxidative stress parameters in the liver and gill of Brazilian flounder juveniles (307.0 ± 16.0 g and 30.0 ± 4.0 cm) submitted to different water temperature (17.1, 23.0 and 28.8ºC) for 72 h and maintained at salinity 25. After the acclimation of 7 days, in 23ºC, fish were transferred to 200 L tanks containing seawater (salinity 25) at 28.8ºC (heat shock), 17.1ºC (cold shock) or 23.0ºC (control), five replicates (five fish tank-1). The sampled collection occurred in 0 (pre-challenge), 3, 24, 48 and 72 h after temperature shock. Flounder exposed to 17.1ºC and 28.8ºC showed significantly higher TBARS levels and GST activity in the liver post-exposition (PE) in relation to the control (23ºC). CAT activity in liver present a significantly increase at 17.1ºC, in first 48 h, and subsequently decrease in 72 h PE in relation to 28.8ºC. The gills of flounder showed significantly higher TBARS levels, GST and CAT activity when submitted at 17.1 and 28.8ºC in relation to 23.0ºC. There were observed changes in lipid peroxidation levels (LPO), CAT and GST activities in the liver and gill of Brazilian flounder in response to reactive oxygen species (ROS) produced by thermal shocks.
O objetivo deste estudo foi determinar os parâmetros de estresse oxidativo no fígado e brânquias de juvenis de linguado (307,0 ± 16,0 g e 30,0 ± 4,0 cm) submetidos a diferentes temperaturas da água (17,1, 23,0 e 28,8ºC) por 72 h e mantidos na salinidade de 25. Após uma aclimatação de sete dias, em 23ºC, os peixes foram transferidos para tanques de 200 L contendo água do mar (salinidade 25) em 28,8ºC (choque quente), 17,1ºC (choque frio) ou 23,0ºC (controle), cinco repetições (cinco peixes/tanque). A coleta de amostras ocorreu em 0 (pré-exposição), 3, 24, 48 e 72 h após o choque térmico. O linguado exposto a 17,1ºC e 28,8ºC apresentaram um significante aumento dos níveis de TBARS e atividade da GST no fígado pós-exposição (PE) em relação ao controle (23ºC). A atividade da CAT no fígado apresentou um aumento significativo em 17,1ºC, nas primeiras 48 h, e subsequente diminuição em 72 h PE em relação a 28,8ºC. As brânquias do linguado apresentaram significante aumento dos níveis de TBARS e atividade da GST e CAT quando submetidos a 17,1ºC e 28,8ºC em relação a 23,0ºC. Foram observadas alterações nos níveis de peroxidação lipídica (LPO) e atividade de GST e CAT no fígado e brânquias de linguado em resposta as espécies reativas de oxigênio (ROS) produzidas pelo choque térmico.
Subject(s)
Animals , Oxidative Stress/physiology , Flatfishes/abnormalities , Flatfishes/physiology , Glutathione S-Transferase pi/analysis , Thiobarbituric Acid Reactive Substances/analysisABSTRACT
Hepatocellular carcinoma [HCC] is one of most frequent cancer in the world, genetic polymorphisms have been reported to play a role in susceptibility to HCC. The present study aimed to study the possible association between glutathione - S - transferase [GSTP] gene polymorphism and susceptibility to HCC. The study was carried out on 120 subjects divided into 3 groups: Group [A] included 60 HCC patients and group [B] included 40 chronic hepatitis C virus patients and group [C] included 20 age and sex matched healthy control. All subjects were submitted to full history taking, liver function tests, GSTPl gene polymorphism by PCR - RFLP. This study found a significant difference between HCC group and each of hepatitis C virus group [HCV] and control group, while there is no significant differences between HCV group and the control group as regarding GSTPl genotyping with the highest percent of ile/val polymorphism [IV] and val/val polymorphism [W] in HCC group and ile/ile [II] polymorphism among HCV and the control group. GSTPl IV genotype frequency was associated with 5.53 times higher risk of HCC than GSTPl II genotype, while GSTPl VV genotype frequency was associated with 6.40 times higher risk of HCC than GSTPl II genotype when compared to the other two groups together. The frequency of GSTPl val [V] allele is higher in HCC when compared to the other two groups together and it was associated with 2.70 timeshigher risk of HCC than GSTP1 I allele. The present study reported that carriage of GSTP1 ile/val and val/val genotypes have a role in susceptibility to HCC and this susceptibility are not through the alteration of the expression of clinical pathological markers and we recommend performance of this work on a large scale to confirm these results