RESUMEN
OBJECTIVE: To investigate the effect of Actinidia chinensis Planch polysaccharide (ACPS) on the growth and apoptosis of human gastric cancer SGC-7901 cells, and to explore the effect of SGC-7901 cells on p-p38 expression. METHODS: The inhibition rates at different concentrations of ACPS on SGC-7901 cells at 24, 48, and 72 h were detected using CCK-8 method. Apoptosis ratios in SGC-7901 were determined by flow cytometry after 48-h treatment of different concentrations of ACPS. The expression of pro-caspase-9, PARP, and p-p38 in SGC-7901 cells after treated by different concentrations of ACPS was detected using Western blot. The expression of pro-caspase-9, PARP, and p-p38 was detected after SGC-7901 cells were pre-treated by p38 specific inhibitor. RESULTS: Compared with the control group, the optical density of SGC-7901 cells decreased after treated by 1, 2.5, 5, and 10 mg/mL ACPS (P < 0.05). Meanwhile, the longer the acting time, the lower the optic density (P < 0.01). IC50 was 7.43 mg/mL at 24 h; 3.88 mg/mL at 48 h, and 1.32 mg/mL at 72 h respectively. ACPS suppressed the protein expression of pro-caspase-9 (P < 0.01) and up-regulated the expression of PARP (89KD) (both P < 0.01). Further study showed that the protein expression of p-p38 was up-regulated in SGC-7901 cells treated by ACPS of different concentrations at 24 h (P < 0.05). The expression of phosphorylation p38 and the ACPS induced apoptosis of SGC-7901 cells could be inhibited after treated by specific inhibitor for 2 h. CONCLUSIONS: ACPS could inhibit the growth of SGC-7901 cells and induce apoptosis. The underlying mechanism of inducing apoptosis was partially due to activating the p38MAPK path and further activating Caspase9 and PARP, finally leading to cell death.
Asunto(s)
Polisacáridos/farmacología , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Actinidia/química , Apoptosis/efectos de los fármacos , Caspasa 9/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Poli(ADP-Ribosa) Polimerasa-1 , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
AIMS: In acute stroke, neurological damage is due to oxidative stress and neuronal apoptotic death. This study investigated whether Nogo-A 290-562 residues region (M9), fused to the transduction domain of the HIV trans-activator (TAT) protein, is neuroprotective against cerebral ischemia and the mechanisms. METHODS: Transient focal cerebral ischemia was induced by middle cerebral artery occlusion in male C57BL/6J mice. TAT-M9, its mutation or vehicle was applied via intraperitoneal injection at the onset of reperfusion. The neurobehavioral scores, infarction volumes, neuronal apoptosis, and the ratio of Bax/Bcl-2 were evaluated. Malondialdehyde (MDA), reactive oxygen species (ROS) levels, and NADPH oxidase activation were measured in the presence or absence of the NADPH oxidase inhibitor apocynin or activator tetrabromocinnamic acid (TBCA). RESULTS: Immunofluorescence results confirmed that TAT-M9 was transduced into brain parenchyma, and it significantly improved neurological behavior, reduced infarct volumes, protected neuronal cells from apoptosis, inhibited activation of NADPH oxidase, and decreased MDA and ROS contents. Furthermore, apocynin imitated the beneficial effects of TAT-M9, while TBCA abolished them. CONCLUSIONS: Our results demonstrate that TAT-M9 administration attenuates cerebral ischemia by inhibiting NADPH oxidase-mediated oxidative damage and neuronal apoptosis in mice. TAT-M9 may be a potential treatment for cerebrovascular disease.
Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Proteínas de la Mielina/uso terapéutico , NADPH Oxidasas/antagonistas & inhibidores , Fármacos Neuroprotectores/uso terapéutico , Fragmentos de Péptidos/uso terapéutico , Superóxidos/metabolismo , Productos del Gen tat del Virus de la Inmunodeficiencia Humana/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Ratones , Ratones Endogámicos C57BL , NADPH Oxidasas/fisiología , Proteínas NogoRESUMEN
OBJECTIVE: To test the hypothesis that spinal cord protection induced by ischemic postconditioning is mediated by an increase of endogenous antioxidant enzyme activities during reperfusion phase in spinal cord. METHODS: Seventy-eight male New Zealand rabbits were randomly divided into 3 groups: Sham group (n = 18) undergoing sham operation without aortic occlusion; ischemia/reperfusion (I/R) group (n = 30) undergoing occlusion of the infrarenal abdominal aorta for 20 min, followed by reperfusion; and postconditioning (PostC) group (n = 30) undergoing occlusion of the infrarenal abdominal aorta for 20 min followed by 3 cycles of 30 s reperfusion/30 s ischemia just at the onset of reperfusion. 30 min, and 1, 3, 6, 24, and 48 h after reperfusion 5 rabbits from each group (and 3 from the Sham group) were killed with their spinal cords taken out, and spectrophotometric method was used to determine the antioxidant enzyme activity and malondialdehyde (MDA) content 6, 24, and 48 h after reperfusion motor function scoring of the hind limbs was conducted. RESULTS: (1) The motor function scores of the PostC group were significantly higher than those of the I/R group 6, 24, and 48 h after reperfusion (all P < 0.05). (2) The activities of superoxide dismutase (SOD) and catalase (CAT) in the spinal cord tissue of the PostC group 30 min-6 h after reperfusion were all significantly higher than those of the I/R group (all P < 0.05). There were no significant differences in the activity of glutathione peroxidase (GSH-px) at different time points between the PostC and I/R groups. (3) The MDA levels 24 h and 48 h after reperfusion of the PostC group were both significantly lower than that of the I/R group (both P < 0.01). CONCLUSION: Ischemic postconditioning shows effect against spinal cord ischemic-reperfusion injury mediated, at least partially, by up-regulating the activities of SOD and CAT in spinal cord during early reperfusion phase.
Asunto(s)
Precondicionamiento Isquémico/métodos , Daño por Reperfusión/metabolismo , Daño por Reperfusión/prevención & control , Isquemia de la Médula Espinal/metabolismo , Isquemia de la Médula Espinal/prevención & control , Animales , Antioxidantes/metabolismo , Catalasa/metabolismo , Modelos Animales de Enfermedad , Masculino , Conejos , Superóxido Dismutasa/metabolismo , Regulación hacia ArribaRESUMEN
OBJECTIVE: To investigate whether postconditioning with sevoflurane could alleviate spinal cord ischemia reperfusion injury in rabbits, and whether the beneficial effect is dependent on oxygen free radicals. METHODS: In Experiment 1, 48 male New Zealand white rabbits were randomly assigned to six groups (n=8 each). Animals in the sham group only underwent sham-operation. Animals in the control group underwent spinal cord ischemia for 20 min without postconditioning. Animals in 02 postconditioning group (Group O2) inhaled 100% O2 from 5 min before reperfusion and lasted 13 min. Animals in sevoflurane postconditioning groups (Group Sevo0.5, Sevo1.0 and Sevo1.5) inhaled 0.5, 1.0, 1.5 minimum alveolar concentration (MAC) sevoflurane in 100% O2 from 5 min before reperfusion and lasted 10 min, then inhaled 100% O2 for 3 min to wash out the remaining sevoflurane. In Experiment 2, 36 male New Zealand White rabbits were randomly assigned to four groups (n=9 each). Animals in O2 and Sevo groups received normal saline (5 ml/kg intravenously) 1 h before postconditioning with 100% O2 and 1.0 MAC sevoflurane, respectively. In the DMTU + Sevo and DMTU + O2 groups, 5 ml/kg of 10% dimethylthiourea (DMTU, a potent oxygen free radical scavenger, dissolved in saline) was administered intravenously at the same time. Spinal cord ischemia was induced by an infrarenal aorta clamping for 20 min. Forty-eight hours after reperfusion, hind-limb motor function and histopathology of the spinal cord were examined in a blinded fashion. RESULTS: (1) The neurologic and histopathologic outcomes in the sevoflurane postconditioning groups were better than those in the control group (P < 0.05), the histopathologic outcomes in Sevo1.0 group were better than that in Sevo0.5 and Sevo1.5 groups (P < 0.05). (2) The neurologic and histopathologic outcomes in Sevo, DMTU + Sevo and DMTU + O2 groups were better than those in the O2 group (P < 0.05), the histopathologic outcomes in Sevo group were better than that in the DMTU + Sevo and DMTU + O2 groups (P < 0.05). CONCLUSIONS: Our study demonstrates that sevoflurane postconditioning against spinal cord ischemia injury via the release of oxygen free radicals in rabbits.