Impact of season on liver mitochondrial oxidative stress and the expression of HSP70 in grey mullets from contaminated estuary

Abstract

Heat shock proteins (HSPs) are the ubiquitous feature of cells in which these proteins cope with stress induced denaturation of other proteins. HSP70 is found to play a primary role in cellular defense under stress condition. In the present investigation, the seasonal impact on environmental stress induced mitochondrial HSP70 (mtHSP70) expression in the liver mitochondria was examined in grey mullets, Mugil cephalus living in the Ennore estuary (polluted site) was compared with the Kovalam estuary (unpolluted site) over the course of two seasons viz monsoon and summer from April 2006 to March 2008. Oxidative stress was determined along with mtHSP70 expression studies in fish liver mitochondria collected from these two estuaries for both the seasons. The liver mitochondria of grey mullet fish collected from polluted Ennore estuary showed increased levels of lipid peroxide and mtHSP70 expression along with decrease in total antioxidant capacity and glutathione redox ratio levels ((c) P < 0.05) when compared to unpolluted Kovalam estuary fish. In the fish liver mitochondria of Ennore estuary, there was significant seasonal variation ((b) P < 0.05) in both oxidative stress marker levels (34% increase) and mitochondrial HSP70 expression (33% increase) with increased level during summer season but the Kovalam estuary fish did not show any significant seasonal variation. In the Ennore estuary fish that are exposed to chronic environmental stress, the overexpression of liver mtHSP70 particularly during summer season may confer differential effects on the cell survival by protection against oxidative stress induced changes.

Biochemical and physiological modifications in tissues of Sardina pilchardus: spatial and temporal patterns as a baseline for biomonitoring studies

“…Considering that both enzymes had their activities significantly induced during warmer periods, which coincided with anabolism/biosynthesis of reserves, it is possible to sustain the occurrence of conditions more favorable to oxidative stress. This is a pattern already demonstrated for other marine fish species, including Zoarces viviparous (Heise et al, 2007), Solea senegalensis (Oliva et al, 2012), and Mugil cephalus (Padmini and Vijaya Geetha, 2009). The discussion of both biomarkers is intrinsically connected, since CAT and GSTs may give further insights into physiological oxidative processes.…”

Effect of L-arginine on HSP70 expression in liver in weanling piglets

“…HSP70 could be used as a marker for assessing the biological behavior under stress in vivo [31]. It has been reported that the overexpression of liver HSP70, particularly during the summer, may confer differential effects on cell survival by protecting against changes induced by oxidative stress [32]. Our results suggest that Arg increased HSP70 mRNA and protein in the liver.…”

Effect of increasing temperature in the differential activity of oxidative stress biomarkers in various tissues of the Rock goby, Gobius paganellus

“…Vinagre et al (2012) also reported an important effect of temperature in the levels of oxidative stress biomarkers in the muscle of D. labrax, in a long term experience, at different temperatures. Mieiro et al (2011) reached the same conclusion analysing the brain of D. labrax and Padmini et al (2009) found that season had an important effect of the levels of oxidative stress biomarkers in the liver of the grey mullet, Mugil cephalus.…”

“…Ferreira et al, 2005;Padmini et al, 2009;Costa et al, 2011;Vinagre et al, 2012;Madeira et al, 2013). Yet, hepatopancreas, digestive gland, gills, blood and hemolymph, have also been frequently used when analysing fish, crustaceans or bivalves (e.g.…”