Antioxidant properties of β-seleno amines against lipid peroxidation in rat brain and liver

Dosing-time dependent oxidative effects of sodium nitroprusside in brain, kidney, and liver of mice

The purpose of this study was to investigate if the oxidative effects of sodium nitroprusside (SNP) are dosing-time dependent. Therefore, the variation of malondialdehyde (MDA) status was assessed after a single i.p. administration of SNP (2.5mgkg(-1) b.w.) or vehicle (9‰ NaCl) to different and comparable groups of mice (n=48) at two different circadian times (1 and 13h after light onset [HALO]). Brain, kidney, and liver tissues were excised over 36h, and their MDA contents were estimated at 0, 1, 3, 6, 9, 12, 24, and 36h after SNP administration.

RESULTS

indicated mean MDA level was not significantly changed in each investigated tissue compared with the control. In contrast, the mean MDA value varied among organs and was comparable in brain and liver but lower than in kidney. The data show SNP significantly (P<0.05) increases MDA status in both tissues and exerts time-dependent oxidative effects with the greatest toxicity coinciding with the beginning of the diurnal rest span (local time: 08:00h, i.e., at 1 HALO). The obtained results reveal SNP-induced oxidative damage (evidenced by MDA accumulation) varies according to both the dosing-time and the target organ.

Antioxidant activity and inhibitory effect of some commonly used medicinal plants against lipid per-oxidation in mice brain

BACKGROUND

The present study compares the protective properties of aqueous extracts of six medicinal plants, Phyllanthus emblica, Terminalia chebula (black and yellow), Terminalia arjuna, Balsamodendron Mukul and Alium sativum against lipid per-oxidation in mice brain.

METHODS

The antioxidant activities were analyzed by lipid per-oxidation assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay, total antioxidant activity and metal chelation.

RESULTS

The extracts (fruits and bark) showed inhibition against thiobarbituric acid reactive species (TBARS) induced by pro-oxidant (10 µM FeSO4) in mice brain. Moreover, the free radical scavenging activities of the extracts was evaluated by the scavenging of DPPH radical (IC₅₀, 23.23 ± 1.2 µg/ml (Phyllanthus emblica), 20.24 ± 0.9 µg/ml (Terminalia chebula yellow) and 17.33 ± 1.1 µg/ml (Terminalia chebula black), 19.44 ± 0.45 µg/ml (Terminalia arjuna), 56.59 ± 2.1 µg/ml (Balsamodendron Mukul) and < 200 µg/ml (Alium sativum).

CONCLUSION

The higher antioxidant and inhibitory effect of Terminalia chebula black in this study could be attributed to its significantly higher phenolic content, Fe(II) chelating ability, reducing ability and free radical scavenging activity. Therefore oxidative stress in brain could be potentially prevented by the intake of these plants.

Evaluation of in vitro antioxidant effect of new mono and diselenides

This study was designed to examine the antioxidant activity in vitro of novel mono- and diselenide compounds. We compared whether the formation of p-methyl-selenol from compounds 1-phenyl-3-(p-tolylselanyl)propan-2-amine (C1) and 1,2-dip-tolyldiselenide (C4) and o-methoxy-selenol from compounds 1-(2-methoxyphenylselanyl)-3-phenylpropan-2-amine (C2) and 1,2-bis(2-methoxyphenyl)diselenide (C3) may be involved in their antioxidant effects. The compounds were tested against Fe(II) and sodium nitroprusside (SNP)-induced lipid peroxidation in rat brain and liver homogenates. Likewise, the antioxidant capacity of the compounds was assessed by their ability to decolorize the DPPH radical as well as the Fe(II) chelating assay through the reduction of molybdenum(VI) (Mo6+) to molybdenum(V) (Mo5+). This colorimetric assay was also used to quantify thiol peroxidase (GPx) and oxidase activity and thioredoxin reductase (TrxR) activity. The results showed that the novel selenide compounds inhibit the thiobarbituric acid reactive species (TBARS) induced by different pro-oxidants, but the monoselenides effects were significant only at concentrations higher than the concentrations of the diselenides. Similarly, the total antioxidant activity was higher in the diselenides. Moreover, GPx and TrxR activity was only observed for the diselenides, which indicates that these compounds are more stable selenol molecules than monoselenides.