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The effect of frozen storage at a commercial temperature (−30°C) on the nutritional characteristics of the blue swimming crab Portunus segnis for a period of 120 days was investigated. Lipid and protein oxidation was investigated by analyses of peroxide value, thiobarbituric acid reactive substances, free fatty acids, and advanced oxidation protein products. Results showed significant lipid deterioration with extended storage time and changes in fatty acids composition and lipid classes. From a nutritional standpoint, it would be preferable for human consumption to eat frozen crabs for no more than 30 days as they retain a higher nutritional value. [ABSTRACT FROM AUTHOR]

The aim of this study is to elucidate the toxicity induced by PbCl2, administered in graded doses (1; 2.5; 5 mg/L), in the redox state, in the fatty acid composition and in the histological structure of Mactra corallina digestive glands. Our findings showed a progressive accumulation of Pb in the M. corallina digestive glands in all treated groups. After 5 days of treatment with PbCl2, an increase in H2O2, MDA, PCO, GSH, NPSH and MT levels was observed in the digestive glands of treated groups. Moreover, activities of antioxidant enzymes, such as GPx and CAT, increased while SOD activity decreased in all treated groups, indicating a failure of the antioxidant defense system. Furthermore, the cholinergic function was evaluated by assessing the acetylcholinesterase activity, which was inhibited in all the treated digestive glands compared to the control group. In our experiment, the levels of n-3 (Omega-3) and n-6 (Omega-6) polyunsaturated fatty acids were greatly altered in the groups treated with 5 mg/L of PbCl2 (p < 0.001). Indeed, DHA and EPA decreased significantly in the digestive glands treated with 2.5 and 5 mg/L of PbCl2, respectively. On the other hand, under exposure to the medium and high doses (2.5 and 5 mg/L), arachidonic acid (ARA) and linoleic acid (LA) significantly increased (p < 0.001). These changes in PUFA were confirmed by significant modifications in the polyene and peroxidation indices. The histological findings confirmed the biochemical results. Integrated parameters were used to explore the toxic effect of PbCl2 graded doses in Mactra corallina digestive gland. Metals accumulation in digestive glands of M. corallina was greatly dependent to dose of PbCl2. Metabolic and macromolecules damaging of clams digestive glands were more sensitive at higher PbCl2 doses. Fatty acids composition especially polyunsaturated fatty acids (PUFA) and essentials fatty acids such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in clams digestive glands were intensively altered at higher PbCl2 doses. Inflammation responses revealed in studied tissue. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is among the most deleterious contaminant in the aquatic environment and presents a serious risk to humans and ecosystems. This study evaluated the effects of Hg on oxidative stress biomarkers, DNA integrity and histological structure of the respiratory tree of Holothuria forskali exposed to different concentrations of mercury chloride HgCl2 (0.04, 0.08 and 0.16 mg L−1) for 96 h. Exposure of H. forskali to Hg led to oxidative stress with an increase in Malondialdehyde (MDA), hydrogen peroxide (H2O2), advanced oxidation protein product (AOPP) and protein carbonyls (PCO) levels in the treated groups. Alteration of the antioxidant system was also confirmed by the significant increase in glutathione (GSH), nonprotein thiol (NPSH) and vitamin C contents. Moreover, the enzymatic activity of superoxide dismutase (SOD), Glutathione peroxidase (GPX) and Catalase (CAT) increased significantly. Our research revealed that total Metallothionein (MTs) content enhanced in a dose-dependent manner. Interestingly, the exposure to this metal provoked a decrease in Acetylcholinesterase (AChE) activity. Hg genotoxicity was further evidenced by a random DNA degradation that was observed in the treated groups. The histopathological findings confirmed the biochemical results. Overall, our results indicated that mercury-induced genotoxicity, oxidative damage and histopathological injuries in the respiratory tree of H. forskali. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is a ubiquitous and a major environmental metal pollutant in the aquatic ecosystem. The present study was performed to evaluate the effect of mercury graded doses exposure on oxidative stress, redox status, metallothionein levels and genotoxicity in the intestine of sea cucumber Holothuria forskali. Specimens were exposed for 96 h to three concentrations of Hg (40, 80 and 160 µg/L). Exposure of H. forskali to Hg promoted oxidative stress with an increase in malondialdehyde (MDA), protein carbonyl (PCO) and advanced oxidation protein products (AOPP) levels. An increase of glutathione (GSH), vitamin C (ViteC) and non-protein thiols (NPSH) contents was also observed. Additionally, antioxidant activities of catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) increased especially with the highest doses of Hg indicating a great defense of the antioxidant system. Our investigation revealed an increase in total Metallothionein (MT) content which was more pronounced at the sharpest concentrations of Hg. A significant decline of AChE activity was also observed. In the intestine of Hg-treated H. forskali genotoxicity was confirmed by DNA degradation. [ABSTRACT FROM AUTHOR]

Context: Barium (Ba) may induce oxidative stress leading to tissues injury. Objective: Our study investigated the therapeutic efficiency of zinc (Zn) and selenium (Se) against neurotoxicity induced by Ba in adult rats and their progeny. Material and methods: Pregnant rats are exposed either to Ba (67 ppm), Ba + Zn, Ba + S or to only Zn and Se. Results: In Ba-treated rats, there was an increase of MDA, H2O2, AOPP levels and SOD activity in the cerebellum of dams and their pups, a decrease in GPx, CAT, AChE, Na+K+-ATPase and Mg2+-ATPase activities, GSH and NPSH levels. These changes were confirmed by histological damages. Co‐administration of Zn or Se to Ba-treated rats ameliorated the biochemical and histological aspects. Conclusion: Our results revealed that Zn and Se have shown promising effects against Ba toxicity in the cerebellum of adult rats and their suckling pups. [ABSTRACT FROM AUTHOR]

Context:Nitraria retusa(Forssk.) Asch. (Nitrariaceae) is a medicinal plant which produces edible fruits whose antioxidant activity has been demonstrated. Objective:The current study elucidates the potential protective effect ofN. retusafruit aqueous extract against nephrotoxicity induced by penconazole, a triazole fungicide, in the kidney of adult rats. Materials and methods:Adult Wistar rats were exposed either to penconazole (67 mg/kg body weight), or toN. retusaextract (300 mg/kg body weight) or to their combination. Penconazole was administered by intra-peritoneal injection every 2 days from day 7 until day 15, the sacrifice day, whileN. retusaextract was administered daily by gavage during 15 days. Oxidative stress parameters, kidney biomarkers and histopathological examination were determined. Results:Nitraria retusaextract administration to penconazole treated rats decreased kidney levels of malondialdehyde (−10%), hydrogen peroxide (−12%), protein carbonyls (PCOs, −11%) and advanced oxidation protein products (AOPP, −16%); antioxidant enzyme activities: catalase (−13%), superoxide dismutase (−8%) and glutathione peroxidase (GPx, −14%), and the levels of non-enzymatic antioxidants: non-protein thiols (−9%), glutathione (−7%) and metallothionein (−12%). Furthermore, this plant extract prevented kidney biomarker changes by reducing plasma levels of creatinine, urea, uric acid and LDH and increasing those of ALP and GGT. Histopathological alterations induced by penconazole (glomeruli fragmentation, Bowman’s space enlargement, tubular epithelial cells necrosis and infiltration of inflammatory leucocytes) were attenuated followingN. retusaadministration. Discussion and conclusion:Our results indicated thatN. retusafruit extract had protective effects against penconazole-induced kidney injury, which could be attributed to its phenolic compounds. [ABSTRACT FROM PUBLISHER]

The protective effect ofNitraria retusafruit extract against hepatotoxicity induced by penconazole at a dose of 67 mg/kg body weight given intraperitoneally every two days to male Wistar rats was investigated. Penconazole exposure increased malondialdehyde, hydrogen peroxide, and advanced oxidation protein product levels. Hepatic biomarkers as well as enzymatic (catalase, superoxide dismutase and glutathione peroxidase) and nonenzymatic (vitamin C, non-protein thiols and metallothioneins) antioxidant status were also altered. Treatment withN. retusaextract improved all parameters cited above. Liver histological studies confirmed the biochemical parameters. These results provide a scientific basis for the use ofN. retusafruit against hepatotoxicity. [ABSTRACT FROM AUTHOR]