Lipid peroxidation was involved in the memory impairment of carbon monoxide-induced delayed neuron damage.

Carbon monoxide (CO)-induced delayed neuron damage is the serious complication, but the underlying mechanisms are poorly understood. This study was designed to investigate the time-dependent changes of the lipid peroxidation (malondialdehyde, MDA) and antioxidative status (glutathione, GSH; glutathione peroxidase, GSH-Px; glutathione reductase, GR; and anti-reactive oxygen species anti-ROS) in nerve tissues for the possible mechanisms exploration. Adult rats were treated with CO by peritoneal injection, and sacrificed after day 0, 1, 3, 7, 14 and 21 of treatment. The results showed that the step-down latency progressively shortened while the numbers of error increased. Comparing with the level of day 0, MDA levels in serum, cerebral cortex and hippocampus significantly increased on day 1, 3 and 7. The level of GSH increased firstly but then decreased. The activities of GR, GSH-Px, and anti-ROS decreased in serum, cerebral cortex and hippocampus of rats after day 1, 3, 7, 14 and 21. Thus, we concluded that CO-mediated delayed neuron damage might be associated with elevation of lipid peroxidation and reduction of antioxidative status. The time-dependent changes of lipid peroxidation and antioxidative status in serum, cerebral cortex and hippocampus, at least in part, are involved in the toxic effects of CO poisoning on neuron.

[Effects of garlic oil on n-hexane metabolized to 2, 5-hexanedione in mice serum].

OBJECTIVE: To investigate the effects of garlic oil (GO) on n-hexane metabolized to 2, 5-hexanedione (2, 5-HD) in mice. METHODS: Adult healthy Kunming-mice were treated with n-hexane and GO. The serum was obtained and extracted with ethyl acetate, and the levels of the serum 2, 5-HD were determined by gas chromatography. RESULTS: (1) The concentration of 2, 5-HD in serum increased firstly after a single exposure to n-hexane (4 000 mg/kg). The peak value occurred at 10 hours after n-hexane treatment, but could hardly be detected at 20 h. (2) There was no 2, 5-HD in serum of control mice. The content of 2, 5-HD in serum increased along with the exposure dose of n-hexane. The serum 2, 5-HD contents of the 2000, 4000 and 6000 mg/kg groups mice were 8.04, 16.68 and 22.38 microg/ml at 8 h in pretreated mice, respectively, and showed significant dose-effect relationship. (3) When the different age mice were exposed to the same dose of n-hexane, the contents of 2, 5-HD in serum were significantly different after 8 hours (P<0.05). The serum 2, 5-HD level of the 5 weeks old mice (22.83 microg/ml) was much higher than the 4 (19.59 microg/ml) and 6 (16.42 microg/ml) weeks old mice. (4) When the different gender mice were exposed to the same dose of n-hexane, the concentration of 2, 5-HD in serum of female mice (13.22 microg/ml) was higher than that of the female mice (10.34 microg/ml, P<0.05). (5) GO significantly inhibited the increase of the serum 2, 5-HD levels of both the pretreatment and post-treatment groups treated with 80 mg/kg n-hexane respectively, but the pretreatment with GO exhibited the more suppressive effects than the post-treatment (P>0.05). Compared with the n-hexane group, the concentrations of serum 2, 5-HD in GO-pretreated groups mice decreased by 16.2%, 20.8%, 22.8% (P<0.05) and 32.1% (P<0.01), respectively, and showed significant dose-effect relationship. CONCLUSION: The serum content of 2, 5-HD, the metabolite of n-hexane, is different in different genders and age mice after exposed to the same dose of n-hexane. GO can effectively inhibit the production of n-hexane metabolized to 2, 5-HD in mice serum.

[Effects of garlic oil on 2, 5-HD induced lipid peroxidation damage in rat nerve tissues].

OBJECTIVE: To investigate the effects of garlic oil (GO) against the peroxidation damage of rat nerve tissue and the peripheral motor neuropathy induced by 2, 5-HD. METHODS: Male Wistar rats were divided into four groups, with 10 in each group. The model group, and low and high doses of GO groups were administrated with 2, 5-HD (ip, 300 mg/kg), respectively; The control group was treated with sodium chloride, five times per week for six weeks. Pretreatment with GO gavaged (40 mg/kg or 80 mg/kg) started one week be-fore 2, 5-HD treatment, and lasted to the end of the experiment. Neurobehavioral indexes were examined at the zero, second and fourth week. At the end of the experiment, the scores of the gait, and the concentration of MDA and GSH, the level of TAOC and the ability of inhibition of.OH in cerebrum, spinal cord and sciatic nerve were examined. RESULTS: Compared with the zero week, except of the control group rats, the hind limb landing foot splay of three groups rats decreased by 44%, 50% and 49% at the fourth week, respectively without significant difference. The threshold value of balance in model, GO low and high doses groups rats decreased by 30%, 45% and 68% at the fourth week, respectively, and lower than the control group rats (P < 0.01). GO low and high doses groups rats showed the serious abnormality at the fourth week, before one week of the model group rats. The scores of gait of model, and GO low and high doses groups rats increased significantly compared with control group rats, and the GO high dose group rats were higher than model group rats (P < 0.05). Increase of the concentration of MDA, and decrease of the level of the ability of inhibition of.OH were induced by 2, 5-HD in cerebrum, spinal cord and sciatic nerve. The concentration of MDA increased, and the level of the ability of inhibition of.OH decreased (P < 0.05 or P < 0.01), respectively. The results showed that the concentration of MDA decreased, and the level of the ability of inhibition of.OH induced by GO in cerebrum, spinal cord and sciatic nerve increased, the concentration of MDA of GO low doses group rats decreased, the level of the ability of inhibition of.OH increased, the concentration of MDA of GO high doses group rats decreased (P < 0.01) respectively, and the level of the ability of inhibition of.OH increased (P < 0.01) in nerve tissue. CONCLUSION: GO has antagonist effect on the 2, 5-HD induced peroxidation damage, but can not improve the function of the peripheral motor nerve, indicating that the lipid peroxidation does not play an important role in 2, 5-HD neurotoxicity.

The anti-fatty liver effects of garlic oil on acute ethanol-exposed mice.

The protective effects of single dose of garlic oil (GO) on acute ethanol-induced fatty liver were investigated. Mice were treated with ethanol (4.8 g/kg bw) to induce acute fatty liver. The liver index, the serum and hepatic triglyceride (TG) levels and the histological changes were examined to evaluate the protective effects. Hepatic malondialdehyde (MDA), glutathione (GSH) levels and superoxide dismutase (SOD), glutathione reductase (GR), glutathione peroxidase (GSH-Px), glutathione-S-transferase (GST) activities were determined for the antioxidant capacity assay. Acute ethanol exposure resulted in the enlargement of the liver index and the increase of the serum and hepatic TG levels (P<0.01), which were dramatically attenuated by GO pretreatment in a dose-dependent manner (P<0.01). GO treatment (simultaneously with ethanol exposure) exhibited similar effects to those of pretreatment, while no obviously protective effects were displayed when it was used at 2h after ethanol intake. Histological changes were paralleled to these indices. Beside this, GO dramatically prolonged the drunken time and shortened the waking time, and these effects were superior to those of silymarin and tea polyphenol. In addition, GO dose-dependently suppressed the elevation of MDA levels, restored the GSH levels and enhanced the SOD, GR and GST activities. Compared with the ethanol group, the MDA levels decreased by 14.2% (P<0.05), 29.9% and 32.8% (P<0.01) in GO groups 50, 100 and 200 mg/kg, respectively. The GST activity increased by 9.97%, 19.94% (P<0.05) and 42.12% (P<0.01) of the ethanol group in GO groups 50, 100 and 200 mg/kg, respectively, while the GR activity increased by 28.57% (P<0.05), 37.97% (P<0.01), 50.45% (P<0.01) of the ethanol group in GO groups 50, 100 and 200 mg/kg, respectively. These data indicated that single dose of GO possessed ability to prevent acute ethanol-induced fatty liver, but may lose its capacity when used after ethanol exposure. The protective effects should be associated with its antioxidative activities.