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Objective To observe the toxicity of low concentration Mn2+ compound combined with autophagy inhibitor chloroquine on nerve cell line PC12 cells for long-term and its mechanism. Methods PC12 cells at logarithmic growth stage were treated with 0 (control), 5, 10, 25, 50, 100, and 200 μM manganous chloride, and 5, 10, 25, 50, and 100 μM chloroquine for 24 h, respectively. The effect of manganous chloride and chloroquine on cell viability was detected by MTT assay. The combined effect of the two compounds on cell viability was determined at 24, 48 and 72 h, respectively. The mitochondrial respiratory function was further examined to explore the possible toxicity mechanism of manganous chloride and chloroquine. Results Compared with the control group, manganous chloride and chloroquine alone had inhibitory effect on cells survival in a concentration-dependent manner. Manganous chloride and chloroquine at concentrations of 40 μM and 2.5 μM, respectively, had no significant effect on cell survival. Compared with the control group, administration of 2.5 μM chloroquine alone for 24, 48 and 72 h did not significantly change cell survival and mitochondrial respiratory function. Treatment of cells with manganous chloride alone at the concentration of 40 μM for 72 h did affect mitochondrial respiratory function. However, the cell survival and mitochondrial respiratory function in the combined administration of manganous chloride and chloroquine for 72 h were significant decreased (P< 0.05). Conclusion The long-term combination of low-concentration manganous chloride and chloroquine produced an additive cytotoxicity on PC12 cells, and the toxicity mechanism may be related to the damage of mitochondrial function.
RESUMO
Objective To investigate the effects of Rhizoma Alismatis extracts on oxidative stress induced by cerebral ischemia-reperfusion injury in rats,and to explore its protective mechanism in cerebral ischemia-reperfusion injury.Methods A total of 60 male SD rats were randomly divided into sham operation group,model group,Alisma orientalis group and Nimodipine positive control group (n=15,each).Cerebral ischemia-reperfusion injury model was prepared by suture method after 14 days of intragastric administration.After 24 hours,scores of neurological dysfunction,the infarct size,the water content of the brain,the malondialdehyde (MDA),superoxide dismutase (SOD),nitric oxide (NO) levels in serum and brain tissues,and the activity of inducible NO synthase (iNOS)were detected.Results As compared with the model group,Alisma orientalis group showed that the scores of neurological dysfunction,cerebral water content,cerebral infarction size,contents of MDA and NO,and the activity of iNOS were significantly reduced,and the activity of SOD was significantly increased in respectively [(2.21 ± 0.38) vs.(2.78 ± 0.43),(81.18 ± 2.09)％ vs.(88.33±4.15)％,(0.26±0.07) ％ vs.(0.35±0.04)％,(5.92±1.64) μmol/L vs.(8.21±1.47)μmol/L,(115.48±18.65) mU/L vs.(75.52±20.78) mU/L,(28.23±4.32) μmol/L vs.(41.73±3.85) μmol/L,(15.31±1.68) mU/L vs.(23.49±3.53) mU/L,(5.41±0.68) μmol/L vs.(7.58±1.49) μmol/L,(168.57±10.65) mU/L vs.(150.11±13.62) mU/L,(14.37±0.77) μmol/L vs.(22.08±1.57) μmol/L,(9.83±0.75) mU/L vs.(13.28±1.84) mU/L,respectively,all P＜0.05]Conclusions Alisma orientalis extract has the protective effect on focal cerebral ischemia reperfusion injury,and the mechanism may be related to antioxidant and scavenging free radicals.