ABSTRACT
Objective:To evaluate the effects of endothelial progenitor cell (EPC)-derived exosomes on neuronal injury induced by oxygen-glucose deprivation and restoration (OGD/R).Methods:HT22 neurons of mice were cultured and divided into 3 groups ( n=30 each) using a random number table method: control group (C group), OGD/R group and OGD/R plus EPC-derived exosome group (OGD/R+ EXO group). Cells in group C were cultured in normal atmosphere.In group OGD/R, the cells were exposed to 94%N 2-1%O 2-5%CO 2 for 6 h in glucose- and serum-free DMEM medium, followed by 24 h restoration of O 2 and glucose in the normal medium.In group OGD/R+ EXO, 20 μg/ml EPC-derived exosomes were added to the culture medium at 24 h before developing the model.EPCs were identified by immunofluorescence staining.Exosomes were identified by Western blot, transmission electron microscopy (TEM) and nanoparticle tracking analysis (NTA). Cell viability was measured by CCK-8 assay, the levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were determined by enzyme-linked immunosorbent assay.The neuronal apoptosis was detected by TUNEL staining, and the apoptosis rate was calculated.The expression of Bax, Bcl-2, caspase-3, and cleaved caspase-3 was determined by Western blot, and cleaved caspase-3/caspase-3 ratio was calculated. Results:The cultured cells were EPCs, and EPC-derived exosomes were successfully extracted.Compared with group C, the cell viability was significantly decreased, the content of MDA was increased, the activity of SOD was decreased, the apoptosis rate was increased, the expression of Bax was up-regulated, the expression of Bcl-2 was down-regulated, and the ratio of cleaved-caspase-3/caspase-3 was increased in group OGD/R and group OGD/R+ EXO ( P<0.05). Compared with group OGD/R, the cell viability was significantly increased, the content of MDA was decreased, the activity of SOD was increased, the apoptosis rate was decreased, the expression of Bax was down-regulated, the expression of Bcl-2 was up-regulated, and the ratio of cleaved-caspase-3/caspase-3 was decreased in group OGD/R+ EXO ( P<0.05). Conclusions:EPC-derived exosomes can reduce OGD/R-induced neuronal injury, which is related to inhibition of oxidative stress and neuronal apoptosis.
ABSTRACT
Objective:To evaluate the role of hippocampal β-amyloid 42 (Aβ 42) deposition-induced accumulation of neutrophils in blood-brain barrier damage caused by sevoflurane anesthesia in aged rats. Methods:Seventy-two healthy male Wistar rats in which IT catheters were successfully planted, aged 18-20 months, weighing 600-650 g, were divided into 4 groups ( n=18 each) using a random number table method: control group (group C), γ-secretase inhibitor DAPT group (group D), sevoflurane anesthesia group (group S) and DAPT plus sevoflurane anesthesia group (group DS). Dimethyl sulfoxide 10 μl was intrathecally injected in group C and group S, and 30 min later group C inhaled 60% oxygen for 2 h, and group S inhaled 3.6% sevoflurane and 60% oxygen for 2 h and tibial fracture surgery was performed at the same time.DAPT 10 μl was intrathecally injected in group D and group DS, and 30 min later group D inhaled 60% oxygen for 2 h, and group DS inhaled 3.6% sevoflurane and 60% oxygen for 2 h and tibial fracture surgery was performed at the same time.The fear conditioning test was performed at 12 h after the end of treatment in each group, and the ratio of time spent freezing was calculated.The rats were sacrificed after the end of behavioral test, and hippocampal tissues were removed for determination of the expression of Aβ 42, occludin and matrix metalloproteinase-9 (MMP-9) (by Western blot), neutrophil count (by immuno-histochemistry), and content of Evans blue (EB) (by EB staining). Results:Compared with group C, the ratio of time spent freezing was significantly decreased, the expression of Aβ 42 and MMP-9 was up-regulated, the expression of occludin was down-regulated, the neutrophil count and content of EB were increased in group S and group DS ( P<0.05), and no significant change was found in the parameters mentioned above in group D ( P>0.05). Compared with group S, the ratio of time spent freezing was significantly increased, the expression of Aβ 42 and MMP-9 was down-regulated, the expression of occludin was up-regulated, the neutrophil count and content of EB were decreased in group DS ( P<0.05). Conclusion:The mechanism by which sevoflurane anesthesia leads to postoperative cognitive dysfunction is related to hippocampal Aβ 42 deposition-induced accumulation of neutrophils and causing damage to blood-brain barrier in aged rats.
ABSTRACT
Objective:To evaluate the role of hemopexin (HPX) in cerebral ischemia-reperfusion (I/R) injury in rats.Methods:One hundred and twenty healthy male Sprague-Dawley rats, aged 7-8 weeks, weighing 250-280 g, were divided into sham operation group (S group, n=36), cerebral I/R group (I/R group, n=36), vehicle group (V group, n=24), and HPX group ( n=24). The model of cerebral I/R injury was established by 120 min middle cerebral artery occlusion followed by reperfusion in anesthetized rats.At 6, 12 and 24 h of reperfusion, 4 rats in S group and I/R group were sacrificed, and the ischemic penumbra of the ipsilateral cerebral cortex was obtained to detect the expression of HPX by Western blot.In I/R, V and HPX groups, 0.9% normal saline 10 μl, 0.1% NaN 3 10 μl, and 1.86 mg/ml HPX 10 μl were injected into the lateral ventricle, respectively, immediately after reperfusion.Eight rats in each group were selected, and neurological deficit was scored at 1-7 days of reperfusion.Eight rats in each group were sacrificed at 1 and 7 days of reperfusion, brains were removed, and brain tissues were obtained for measurement of infarct size, and the percentage of infarct size was calculated. Results:Compared with S group, the expression of HPX in cerebral ischemic penumbra was significantly up-regulated at 24 h of reperfusion in I/R group, and the neurological deficit scores were significantly decreased at 1-7 days of reperfusion, and the percentage of cerebral infarct size was increased at 1 and 7 days of reperfusion in I/R, V and HPX groups ( P<0.05). Compared with I/R group, the neurological deficit scores were significantly increased at 1-7 days of reperfusion, and the percentage of cerebral infarct size was decreased at 1 and 7 days of reperfusion in HPX group ( P<0.05), and no significant change was found in the above indicators in V and I/R groups ( P>0.05). Conclusion:Up-regulation of HPX expression is the endogenous protective mechanism of cerebral I/R injury in rats.
ABSTRACT
Objective:To evaluate the effect of the semisolid food on the energy supplement in the parturients undergoing epidural labor analgesia.Methods:Ninety parturients requesting epidural labor analgesia with no pregnancy complications, at 38-41 week gestation, aged 20-35 yr, with body mass index of 19-30 kg/m 2, were divided into 3 groups ( n=30 each) using a random number table method: sports drink group (group A), millet gruel group (group B) and semisolid food group (group C). After admission to the hospital, different types of food were given on an empty stomach after drinking 300 ml of water, before labor analgesia and 1 h of labor analgesia, and the gastric emptying time (GET) was measured by the ultrasound assessment of gastric antrum.In the late stage of labor analgesia, patients drank different types of food as needed until the end of the third stage of labor.Visual analogue scale score was used to evaluate the maternal starvation, thirst and fatigue immediately after the end of the third stage of labor.The duration of labor, total amount of diet, energy supply per unit time, forceps-assisted vaginal delivery, pressing times of patient-controlled analgesia, occurrence of nausea and vomiting during labor, and volume of postpartum hemorrhage were recorded. Results:GET was significantly longer after labor analgesia than before labor analgesia in the three groups ( P<0.05). Compared with group A, GET was significantly prolonged after labor analgesia, scores for starvation and fatigue and total amount of diet were decreased, and the energy supply per unit time was increased in group B and group C, and the incidence of nausea and vomiting was significantly increased in group B and decreased in group C ( P<0.05). Compared with group B, GET was significantly shortened after labor analgesia, scores for fatigue were decreased, the energy supply per unit time was increased, and the incidence of vomiting was decreased in group C ( P<0.05). There were no statistically significant differences among the three groups in scores for thirst, duration of labor, incidence of forceps-assisted vaginal delivery, volume of postpartum hemorrhage, and pressing times of patient-controlled analgesia ( P>0.05). Conclusion:Compared with sports drinks and millet gruel, semi-solid food is more effective in supplementing energy for the parturients undergoing epidural labor analgesia.
ABSTRACT
Objective:To evaluate the role of heme oxygenase-1 (HO-1) in hemopexin (HPX)-induced reduction of cerebral ischemia-reperfusion (I/R) injury in rats.Methods:One hundred and eighty male Sprague-Dawley rats, aged 7-8 weeks, weighing 250-280 g, were divided into 5 groups ( n=36 each) using a random number table method: sham operation group (group SH), I/R group, vehicle group (group V), HPX group, and HPX plus HO-1 specific inhibitor ZnPPIX(HZ group). Local cerebral I/R was produced by middle cerebral artery occlusion for 120 min followed by reperfusion in anesthetized rats.In I/R, V, HPX and HZ groups, 0.9% normal saline 10 μl, 0.1% NaN 3 10 μl, 1.86 g/L HPX (diluted to 10 μl in 0.1% NaN 3 solution), and 1.86 g/L+ ZnPPIX 20 μmol/L (diluted to 10 μl in 0.1% NaN 3 solution) were injected through the lateral ventricle, respectively, immediately after onset of reperfusion.Morris water maze test was used to detect the cognitive function on day 1 before ischemia and day 2 of reperfusion.Rats were sacrificed, brains were removed and brain tissues were obtained for determination of the permeability ratio of Evans blue (EB), brain water content, expression of VE-cadherin in ischemic penumbra (by Western blot), and expression of angiopoietin-1 (Ang1) mRNA and Ang2 mRNA (by real-time polymerase chain reaction). Ang1 mRNA/Ang2 mRNA ratio was calculated.CD31/vWF double labeling immunofluorescence was used to detect the density of neovascularization in hippocampal tissues in the ischemic penumbra. Results:Compared with SH group, the escape latency was significantly prolonged at 2-7 days of reperfusion, the percentage of time of staying at the target quadrant was decreased, the frequency of crossing the platform was decreased, the permeability ratio of EB in brain tissues was increased at day 7 of reperfusion, and the brain water content, Ang1 mRNA/Ang2 mRNA ratio, expression of VE-cadherin and density of neovascularization were decreased in I/R, V, HPX and HZ groups ( P<0.05). Compared with I/R group, the escape latency was significantly shortened at 2-7 days of reperfusion, the percentage of time of staying at the target quadrant was increased, the frequency of crossing the platform was increased, the permeability ratio of EB in brain tissues was decreased at day 7 of reperfusion, and the brain water content, Ang1 mRNA/Ang2 mRNA ratio, expression of VE-cadherin and density of neovascularization were increased in HPX group ( P<0.05), and no significant change was found in the parameters mentioned above in V and HZ groups ( P>0.05). Compared with HPX group, the escape latency was significantly prolonged at 2-7 days of reperfusion, the percentage of time of staying at the target quadrant was decreased, the frequency of crossing the platform was decreased, the permeability ratio of EB in brain tissues was increased at day 7 of reperfusion, and the brain water content, Ang1 mRNA/Ang2 mRNA ratio, expression of VE-cadherin and density of neovascularization were decreased in HZ group ( P<0.05). Conclusion:HO-1 is involved in HPX-induced reduction of cerebral I/R injury in rats.
ABSTRACT
Objective To explore the potential effects of endothelial progenitor cells (EPCs)-angiogenesis on mechanism of alleviating cognitive dysfunction in rats subjected to cerebral ischemia-reperfusion (I/R) injury. Methods A total of 121 male Sprague–Dawley (SD) rats were randomly divided into four groups:Sham group (n=31), focal I/R(MCAO, 0.9%saline 10μL, n=30) group, MCAO+Vehicle (sodium azide, 0.1%Vehicle 10μL, n=30) group and MCAO+HPX (1.86 g/L HPX 10μL, n=30) group. The modified neurological severity scores (mNSS) was carried out to determine neurological function deficit after I/R. Morris water maze (MWM) was carried out to assess learning and memory abilities after I/R. The circulating EPCs after I/R were counted by flowcytometry (FCM) combined with double-immunofluorescence staining of CD34 and CD133. Angiogenesis in rat penumbra cortex after I/R was assessed by immunohistochemical technique combined with immunofluorescent chromogenic detection of CD31 and vWF. Results Compared with sham group, the mNSS scores, the escape latency and the circulating EPCs count were increased after I/R, the time percentage spent in target quadrant was reduced, and the new vessel density in penumbra cortex was increased after I/R in MCAO group (P 0.05). The mNSS score and the escape latency were significantly decreased, the circulating EPCs count and new vessel density in penumbra cortex were significantly increased after I/R in MCAO+HPX group compared with those of MCAO+Vehicle and MCAO group (P<0.05). Conclusion EPCs-angiogenesis signaling plays positive effects on HPX alleviating cognitive dysfunction in rats subjected to focal cerebral ischemia reperfusion injury.