Abstract

The effect of the antioxidant gallic acid (GA) on Pb toxicity in blood, liver and kidney was investigated in the present study. Rats Wistar received Pb nitrate (50 mg/Kg/day, i.p., 5 days) followed by GA (13.5 mg/Kg, p.o., 3 days) or a chelating agent (EDTA, 55 mg/Kg, i.p.). As result, Pb decreased body weight, hematocrit and blood δ-aminolevulinic acid dehydratase (ALA-D) activity. In addition, high Pb levels were observed in blood and tissues, together with increased (1) lipid peroxidation in erythrocytes, plasma and tissues, (2) protein oxidation in tissues and (3) plasma aspartate transaminase (AST) levels. These changes were accompanied by decreasing in antioxidant defenses, like superoxide dismutase (SOD) activity in tissues and catalase (CAT) activity and reduced glutathione (GSH) in liver. GA was able to reverse Pb-induced decrease in body weight and ALA-D activity, as well as Pb-induced oxidative damages and most antioxidant alterations, however it did not decrease Pb bioaccumulation herein as EDTA did. Furthermore, EDTA did not show antioxidant protection in Pb-treated animals as GA did. In conclusion, GA decreased Pb-induced oxidative damages not by decreasing Pb bioaccumulation, but by improving antioxidant defenses, thus GA may be promising in the treatment of Pb intoxications.

Abstract

Cisplatin (CP) is a potent anti-cancer drug widely used against solid tumors. However, it exhibits pronounced adverse effects including hepatotoxicity. Several strategies were attempted to prevent CP hepatotoxicity but were not found suitable for therapeutic application. Nigella sativa has been shown to prevent/reduce the progression of certain type of cardiovascular, kidney and liver diseases. Present study investigates whether N. sativa oil (NSO) can prevent CP induced hepatotoxic effects. Rats were divided into four groups viz. control, CP, NSO and CPNSO. Animals in CPNSO and NSO group were administered NSO (2 ml/kg bwt, orally) with or without single hepatotoxic dose of CP (6 mg/kg bwt, i.p.) respectively. CP hepatotoxicity was recorded by increased serum ALT and AST activities. CP treatment caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation and decreased enzymatic and non-enzymatic antioxidants. Furthermore, the activities of various carbohydrate metabolism and membrane enzymes were altered by CP treatment. In contrast, NSO administration to CP treated rats, markedly ameliorated the CP elicited deleterious alterations in liver. Histopathological observations showed extensive liver damage in CP treated animals while greatly reduced tissue injury in CPNSO group. In conclusion, NSO appears to protect CP induced hepatotoxicity by improving energy metabolism and strengthening antioxidant defense mechanism.

Abstract

Glucose-6-phosphate dehydrogenase (G6PD), a key regulatory enzyme of the pentose phosphate pathway, catalyses the first rate-limiting reaction to produce ribose-5-phosphate for nucleic acid synthesis and NADPH to use in reductive biosynthesis. The available studies indicate an antioxidant role for G6PD and variation in its levels as a result of cellular insult. In this study, the activity of G6PD was monitored during Nʹ-nitrosodiethylamine (NDEA)-induced hepatic damage in Wistar rats. NDEA generates hepatotoxicity and possesses mutagenic effects. To induce hepatic damage, NDEA was administered at doses of 100 mg kg− 1 body weight week− 1 (i.p.) for 14 days. The animals of the control and treated groups were sacrificed each week. The extent of liver damage was ensured by LFT biomarkers, such as transaminases, ALP, bilirubin and the hepato-somatic index (HSI) along with histopathological observations of H&E and Massons trichrome stained liver specimens. The results of the present study show that at the selected doses, NDEA significantly elevates LFT proteins and bilirubin and damages the lobular architecture in a dose-dependent manner. Software analysis of zymograms indicates maximum activity of the hepatic G6PD levels in day-14 NDEA-treated animals. Our spectrophotometry data further support the above findings on hepatic G6PD levels and demonstrate an approximately 1.63 × and 1.66 × fold increase in day-7 and day-14 NDEA intoxicated animals (P < 0.05). It is concluded that elevation in the G6PD activity is apparently the consequence of NDEA-induced intoxication or oxidative stress, leading to hepatic damage to provide sufficient NADPH for microsomal detoxification and ribose-5-phosphate for DNA synthesis and repair, respectively, to maintain the cellular redox status.

Abstract

Macadamia nut is considered "the queen of nuts", because of its high energy content and nutritional value. Certain types of nuts are considered to be non-commercial due to their color; therefore, the aim of this study was determining a method of surface bleaching using additives that do not affect the taste, smell and texture of the walnut. Color is a sensory quality of food; it’s an indicator and a critical quality factor in fresh and processed products. Three food additives were used as bleaching agents: 1% citric acid for 2 minutes and 3% for 1 minute, 0.1% ascorbic acid for 1 minute and 0.3% for 3 minutes, and 5 and 10% sodium bicarbonate for 1 minute. For all treatments, color analysis, walnut moisture, sensory analysis of odor, taste and texture were carried out. Walnuts were bleached superficially after drying. The results indicate that the best treatment for bleaching macadamia nut is ascorbic acid at 0.3%, with this it is possible to add a more homogeneous and natural color to the nut, free of blackish spots.