Assessment of the neuroprotective effect of green synthesized iron oxide nanoparticles capped with curcumin against a rat model of Parkinson's disease.

Objectives: The current study aims to investigate the protective effect of iron oxide nanoparticles capped with curcumin (FeONPs-Cur) against motor impairment and neurochemical changes in a rat model of Parkinson's disease (PD) induced by reserpine. Materials and Methods: Rats were grouped into control, PD model induced by reserpine, and PD model treated with FeONPs-Cur (8 rats/group). The open field test was used to assess motor activity. The concentration of dopamine (DA), norepinephrine (NE), serotonin (5-HT), lipid peroxidation (MDA), reduced glutathione (GSH), and nitric oxide (NO), and the activities of Na+,K+,ATPase, acetylcholinesterase (AchE), and monoamine oxidase (MAO) were determined in the midbrain and striatum. Data were analyzed by ANOVA at P-value<0.05. Results: The PD model exhibited a decrease in motor activity. In the midbrain and striatum of the PD model, DA, NE, and 5-HT levels decreased significantly (P-value<0.05). However, an increase in MAO, NO, and MDA was observed. GSH, AchE and Na+,K+,ATPase decreased significantly in the two brain areas. FeONPs-Cur prevented the decline of dopamine and norepinephrine and reduced oxidative stress in both areas. It also prevented the increased MAO activity in the two areas and the inhibited activity of AchE and Na+,K+,ATPase in the midbrain. These changes were associated with improvements in motor activity. Conclusion: The present data indicate that FeONPs-Cur could prevent the motor deficits induced in the PD rat model by restoring dopamine and norepinephrine in the midbrain and striatum. The antioxidant activity of FeONPs-Cur contributed to its protective effect. These effects nominate FeONPs-Cur as an antiparkinsonian candidate.

Brain and liver oxidative stress after sertraline and haloperidol treatment in mice.

BACKGROUND: Haloperidol is a classic antipsychotic drug known for its propensity to cause extrapyramidal side effects. Sertraline is an antidepressant drug which has been reported to cause extrapyramidal symptoms. We aimed to see whether treatment with sertraline would worsen the effect of haloperidol on oxidative stress in the brains of mice. METHODS: Sertraline (10 or 20 mg/kg), haloperidol (2 mg/kg), haloperidol combined with sertraline or saline was administered daily via the subcutaneous route and mice were euthanized 10 days later when biochemical assays were carried out. Malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (nitrite) levels, total antioxidant capacity (TAC), acetylcholinesterase (AChE), catalase and paraoxonase 1 (PON1) activities were determined in the brain and liver. RESULTS: Sertraline monotherapy did not alter GSH, MDA, TAC or nitrite in the brain. Haloperidol decreased GSH and TAC and increased MDA and nitrite. The combined treatment with sertraline and haloperidol resulted in increased MDA, but to a lesser extent than haloperidol monotherapy. A significant increase in GSH and TAC and decreased nitrite was observed after the combination treatment was compared with haloperidol monotherapy. Catalase activity decreased with sertraline or haloperidol treatment. PON1 activity decreased with sertraline and haloperidol monotherapy and showed a further decrease with the combination therapy compared with haloperidol monotherapy. AChE activity decreased after haloperidol and increased with the combination treatment compared with haloperidol monotherapy. In the liver, GSH was unaltered after sertraline, haloperidol or their combination. MDA increased with sertraline, haloperidol and their combination. TAC decreased after combination therapy. Nitric oxide increased after sertraline, haloperidol or their combination. PON1 activity decreased with sertraline, haloperidol and with sertraline-haloperidol co-treatment. CONCLUSIONS: Sertraline did not worsen brain oxidative stress-induced with haloperidol, however, liver peroxidation increased. Sertraline decreased catalase and PON1 activity which might expose the brain to further oxidative insults.

The effect of gabapentin on oxidative stress in a model of toxic demyelination in rat brain.

BACKGROUND: Gabapentin, a structural analog of γ-aminobutyric acid (GABA), is used in the treatment of neuropathic pain in multiple sclerosis. METHODS: This study investigated the effect of gabapentin on oxidative stress in a model of brain demyelination evoked by intracerebral injection (i.c.i) of ethidium bromide (10 µL of 0.1%). Rats received saline (control) or gabapentin at 100 or 300 mg/kg orally daily for 10 days prior to injection of ethidium bromide. Rats were euthanized 1 day later, and then the levels of reduced glutathione (GSH), glutathione peroxidase (GPx) activity, lipid peroxidation (malondialdehyde; MDA), nitrite, acetyl cholinesterase (AChE) and paraoxonase activities were assessed in the brain cortex in different treatment groups. RESULTS: Ethidium bromide resulted in increased oxidative stress in the cortex 1 day after its injection. Malondialdehyde increased by 30.2%, whereas GSH decreased by 17.6%. GPx activity was inhibited by 78.6%. Brain nitrite increased by 55.4%, AChE activity decreased by 33.4% and paraoxonase activity decreased by 27.5%. In ethidium bromide treated rats, gabapentin administered at 300 mg/kg increased cortical MDA by 66%. GSH was unaltered by gabapentin, but GPx activity decreased by 54.3% by the higher dose of gabapentin. Nitrite decreased by 21.4% and 29.2% after 100 and 300 mg/kg of gabapentin, respectively. AChE activity increased by 28.6% and 69.3% by 100 and 300 mg/kg of gabapentin, respectively. Paraoxonase activity showed 83.3% and 73% decreases by 100 and 300 mg/kg of gabapentin, respectively. CONCLUSIONS: These results suggest that gabapentin increases brain lipid peroxidation and decreases brain antioxidant enzymes in this model of chemical demyelination.

Neuroprotective effect of nitric oxide donor isosorbide-dinitrate against oxidative stress induced by ethidium bromide in rat brain.

This study investigated the effect of systemic administration of isosorbide-dinitrate (ISDN) on oxidative stress and brain monoamines in a toxic model of brain demyelination evoked by intracerebral injection (i.c.i) of ethidium bromide (10 µl of 0.1 %). Rats received saline (control) or ISDN at 5 or 10 mg/kg for 10 days prior to injection of ethidium bromide. Rats were euthanized one day later, and then the levels of reduced glutathione (GSH), lipid peroxidation (malondialdehyde; MDA), nitric oxide (nitrite/nitrate), acetylcholinesterase (AChE) activity, paraoxonase activity as well as monoamine levels (serotonin, dopamine and noradrenaline) were assessed in the brain cortex in different treatment groups. The i.c.i of ethidium bromide resulted in increased oxidative stress in the cortex one day after its injection; (i) MDA increased by 36.9 %; (ii) GSH decreased by 20.8 %, while (iii) nitric oxide increased by 60.3 %; (iv) AChE and paraoxonase activities in cortex decreased by 35.9 % and 29.4 %, respectively; (v) serotonin was significantly increased. In ethidium bromide-treated rats, pretreatment with ISDN at 10 mg/kg decreased cortical MDA by 23.9 %. Reduced glutathione was increased by 25.1 % ISDN at 10 mg/kg, while nitric oxide showed a 32.8 and 41.7 % decrease after 5 and 10 mg/kg of ISDN, respectively. Acetylcholinesterase activity increased by 24.3 % by 10 mg/kg of ISDN. Paraoxonase activity showed further decrease by 72.2 and 83.8 % after treatment with 5 and 10 mg/kg of ISDN, respectively. The administration of ISDN decreased the level of serotonin and noradrenaline compared with the ethidium bromide only treated group. Overall, the present findings suggest neuroprotective effect of ISDN against oxidative stress in this model of chemical demyelination.

Effect of infrared laser irradiation on amino acid neurotransmitters in an epileptic animal model induced by pilocarpine.

OBJECTIVE: The aim of the present study was to investigate the effect of daily laser irradiation on the levels of amino acid neurotransmitters in the cortex and hippocampus in an epileptic animal model induced by pilocarpine. BACKGROUND DATA: It has been claimed that at specific wavelengths and energy densities, laser irradiation is a novel and useful tool for the treatment of peripheral and central nervous system injuries and disorders. MATERIALS AND METHODS: Adult male albino rats were divided into three groups: control rats, pilocarpinized rats (epileptic animal model), and pilocarpinized rats treated daily with laser irradiation (90 mW at 830 nm) for 7 d. The following parameters were assayed in cortex and hippocampus: amino acid neurotransmitters (excitatory: glutamic acid and aspartate; and inhibitory: gamma-aminobutyric acid [GABA], glycine, and taurine) by high-performance liquid chromatography (HPLC), glucose content, and the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), using a spectrophotometer. RESULTS: Significant increases in the concentrations of glutamic acid, glutamine, glycine, and taurine were recorded in the cortices of pilocarpinized rats, and they returned to initial levels after laser treatment. In the hippocampus, a moderate increase in aspartate accompanied by a significant increase in glycine were observed in the epileptic animal model, and these dropped to near-control values after laser treatment. In addition, a significant increase in cortical AST activity and a significant decrease in ALT activity and glucose content were obtained in the pilocarpinized animals and pilocarpinized rats treated with laser irradiation. In the hippocampus, significant decreases in the activity of AST and ALT and glucose content were recorded in the epileptic animals and in the epileptic animals treated with laser irradiation. CONCLUSION: Based on the results obtained in this study, it may be suggested that nearinfrared laser irradiation may reverse the neurochemical changes in amino acid neurotransmitters induced by pilocarpine.

Effect of three different intensities of infrared laser energy on the levels of amino acid neurotransmitters in the cortex and hippocampus of rat brain.

OBJECTIVE: The aim of this study is to investigate the effects of three different intensities of infrared diode laser radiation on amino acid neurotransmitters in the cortex and hippocampus of rat brain. BACKGROUND DATA: Lasers are known to induce different neurological effects such as pain relief, anesthesia, and neurosuppressive effects; however, the precise mechanisms of these effects are not clearly elucidated. Amino acid neurotransmitters (glutamate, aspartate, glutamine, gamma-aminobutyric acid [GABA], glycine, and taurine) play vital roles in the central nervous system (CNS). MATERIALS AND METHODS: The shaved scalp of each rat was exposed to different intensities of infrared laser energy (500, 190, and 90 mW) and then the rats were sacrificed after 1 h, 7 d, and 14 d of daily laser irradiation. The control groups were exposed to the same conditions but without exposure to laser. The concentrations of amino acid neurotransmitters were measured by high-performance liquid chromatography (HPLC). RESULTS: The rats subjected to 500 mW of laser irradiation had a significant decrease in glutamate, aspartate, and taurine in the cortex, and a significant decrease in hippocampal GABA. In the cortices of rats exposed to 190 mW of laser irradiation, an increase in aspartate accompanied by a decrease in glutamine were observed. In the hippocampus, other changes were seen. The rats irradiated with 90 mW showed a decrease in cortical glutamate, aspartate, and glutamine, and an increase in glycine, while in the hippocampus an increase in glutamate, aspartate, and GABA were recorded. CONCLUSION: We conclude that daily laser irradiation at 90 mW produced the most pronounced inhibitory effect in the cortex after 7 d. This finding may explain the reported neurosuppressive effect of infrared laser energy on axonal conduction of hippocampal and cortical tissues of rat brain.