کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1977213 1539283 2015 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
High environmental ammonia elicits differential oxidative stress and antioxidant responses in five different organs of a model estuarine teleost (Dicentrarchus labrax)
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شیمی
پیش نمایش صفحه اول مقاله
High environmental ammonia elicits differential oxidative stress and antioxidant responses in five different organs of a model estuarine teleost (Dicentrarchus labrax)
چکیده انگلیسی

We investigated oxidative status and antioxidant profile in five tissues (brain, liver, gills, muscle and kidney) of European sea bass (Dicentrarchus labrax) when exposed to high environmental ammonia (HEA, 20 mg/L ~ 1.18 mM as NH4HCO3) for 12 h, 2 days, 3.5 days, 7.5 days and 10 days. Results show that HEA triggered ammonia accumulation and induced oxidative stress in all tissues. Unlike other organs, hydrogen peroxide (H2O2) and malondialdehyde (MDA) accumulation in liver were restored to control levels. This recovery was associated with a concomitant augmentation in superoxide dismutase (SOD), catalase (CAT), components of glutathione redox cycle (glutathione peroxidase GPX, glutathione reductase, reduced glutathione), ascorbate peroxidase activity and reduced ascorbate content. On the contrary, in brain during prolonged exposure many of these anti-oxidant enzymes were either unaffected or inhibited, which resulted in persistent over-accumulation of H2O2 and MDA. Branchial and renal tissue both involved in osmo-regulation, revealed an entirely dissimilar compensatory response; the former rely mainly on the ascorbate dependent defensive system while the glutathione catalytic pathway was activated in the latter. In muscle, GPX activity first rose (3.5 days) followed by a subsequent drop, counterbalanced by simultaneous increment of CAT. HEA resulted in a relatively mild oxidative stress in the muscle and kidney, probably explaining the modest anti-oxidative responses. Our findings exemplify that oxidative stress as well as antioxidant potential are qualitatively diverse amongst different tissues, thereby demonstrating that for biomonitoring studies the screening of adaptive responses at organ level should be preferred over whole body response.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology - Volumes 174–175, August–September 2015, Pages 21–31
نویسندگان
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