Ali Mezni

Lithium induced oxidative damage and inflammation in the rat’s heart: Protective effect of grape seed and skin extract

Lithium (Li) is a relevant mood stabilizer metal for the treatment of bipolar disorder (BD), as it protects from both depression and mania and reduces the risk of suicide. However, Lihas some clinical concerns as a narrow therapeutic index requiring routine monitoring of the serum level. The present study was designed to analyze the cardio-toxic side effect of Li and the ability of grape seed and skin extract (GSSE) to protect the heart against such toxicity. After 30days of exposure to Li (0, 2, 5 and 100mg/kg bw) and prevention with GSSE (4000mg/kg bw), rats were killed by decapitation and their heart processed for Li-induced oxidative stress. Data mainly showed that Li increased lipoperoxidation and protein carbonylation, it decreased superoxide dismutase and glutathione peroxidase activities, altered acetylcholinesterase (AChE) activity and increased the pro-inflammatory cytokine interleukin 6 (IL-6). Interestingly, GSSE efficiently alleviated all the deleterious effects of Li especially in low therapeutic doses. Based on our results, GSSE could be proposed as a nutritional supplement to mitigate the cardiotoxic side effects of lithium.

Effect of permethrin (pyrethroid insecticide) on the biochemical response of the freshwater amphipod Echinogammarus tacapensis (Chevreux and Gauthier, 1924)

Abstract Pyrethroids, the widely used pesticides, are highly toxic to aquatic organisms. However, little information is available on their toxicity on crustaceans. We utilized imagoes of Echinogammarus tacapensis to elucidate the effects of sublethal concentrations of permethrin. The LC50 (48, 72, and 96 h) was assessed considering several pesticide concentrations (ranging between 0.5 and 100 ng L−1) using the Regtox package and were found to be 13.88, 8.974, and 4.259 ng L−1, respectively. The biomarkers’ response was analyzed using animals exposed to 0.35, 0.7, and 1.4 ng/L of permethrin for 4 days. The catalase activity was significantly induced after 48 h of exposure to the three permethrin concentrations. Additionally, the glutathione S-transferase activity was increased in a concentration-dependent manner. However, exposed to C1 (0.35 ng L−1), the superoxide dismutase (SOD) activity showed no significant change compared to control values. The hydrogen peroxide (H2O2) rate was found to be similar to the SOD variation. Our findings suggest that permethrin poses a potential threat to freshwater amphipods and thus, the test species can be a useful tool for pesticide toxicity biomonitoring due to their small size, easy husbandry, short life cycle, and high fecundity.

New Organic Acidic Cyclohexaphosphate: Synthesis, Crystal Structure, Physicochemical Study, and In Vitro Biochemical Investigation

A novel organic cyclohexaphosphate [o-(OCH3)C6H4NH3]4H2P6O18·4H2O (1) has been synthesised by the slow evaporation method. An X-ray diffraction study on a single crystal was used to identify this compound. It shows that this acidic cyclohexaphosphate crystallizes in the monoclinic space group P21/n with V 2215.1(1) A3 and Z 2. Its crystal structure is a packing of alternating inorganic and organic layers parallel to the (a, c) planes. Crystal symmetry is confirmed by 31P magic angle spinning-NMR spectroscopy. Furthermore, spectroscopic (IR, UV-visible) and thermal (thermogravimetric/differential thermal analysis and differential scanning calorimetry) characteristics are given. The excitation and emission spectra were recorded showing blue photoluminescence. The alternating current conductivity and dielectric measurements were carried out in the temperature range 333–403 K and the frequency range from 5 Hz to 13 MHz. The impedance data were well fitted to an equivalent electrical circuit. The temperature dependence of the direct current conductivity follows the Arrhenius law and the frequency dependence of σAC(ω,T) follows Jonscher’s universal law. Antioxidant properties of this compound were studied, in vitro, at various concentrations with different tests; 1,1-diphenyl-2-picrylhydrazyl, hydroxyl scavenging ability, ferric reducing power, and ferrous ion chelating ability, using ascorbic acid as control.

Neuroprotective effect of grape seed and skin extract on lithium-induced oxidative stress in healthy rat brain

Lithium is used in the therapy of various psychoses based on its antidepressant and mood stabilizing properties. However it also exerted toxic side effects in long standing treatment. We studied the effect of lithium on brain oxidative stress status into healthy rat as well as the putative protection afforded by grape seed and skin extract, used as an antioxidant and anti-inflammatory agent. Lithium generated an oxidative stress characterized by increased lipoperoxidation and carbonylation, decreased antioxidant enzyme activities as catalase, superoxide dismutase and glutathione peroxidase. Furthermore lithium altered transition metals distribution and associated enzyme activities, increased intracellular mediators as H2O2, free iron, calcium, magnesium and calpain activity but decreased acetylcholinesterase activity. Lithium also disturbed brain lipidemia as evidenced by high triglyceride and cholesterol and low lipase activity. Almost all deleterious effects of lithium were normalized by grape seed and skin extract especially at the therapeutic doses of lithium. Grape seed and skin extract could be proposed as an efficient neuroprotectant to mitigate the adverse side effects of lithium.