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ABSTRACT: Autophagy, a process for the degradation of protein aggregates and dysfunctional organelles, is required for cellular homeostasis and cell survival in response to stress and is implicated in endogenous protection. Ischemic preconditioning is a brief and nonlethal episode of ischemia, confers protection against subsequent ischemia-reperfusion through the up-regulation of endogenous protective mechanisms. Emerging evidence shows that autophagy is associated with the protective effect of ischemic preconditioning. This review summarizes recent progress in research on the functions and regulations of the autophagy pathway in preconditioning-induced protection and cellular survival.
Acta Pharmacologica Sinica 04/2013; · 1.95 Impact Factor
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ABSTRACT: Hemopexin (HPX) is a plasma protein with the strongest binding capacity to heme and widely involved in modulation of a variety of physiological and pathological processes. The main physiological function of HPX is to bind and transport free toxic heme. Recent studies indicate that HPX also plays roles of anti-oxidant, anti-apoptosis, immune regulation and organic protection. In addition, HPX participates in regulation of cell differentiation and extracellular matrix reconstruction. In recent years, a great deal of progress has been made in studies of the mechanisms of HPX protective effects and on possible clinical application. In the past few years, especially, a number of proteomic studies have demonstrated that HPX could be served as positive molecular biomarkers for cancers of lung, liver, kidney, colon, and uterine myoma as well as osteoarthritis. In this review, recent progress in the biochemical characteristics and function of HPX and its possible clinical applications are summarized.
Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology 03/2013; 21(2):513-6.
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ABSTRACT: To investigate the effects of electromagnetic pulse irradiation on the mouse blood-testicle barrier (BTB) and spermatogenesis.
After whole body irradiation with 400 kV/m electromagnetic pulse irradiation, the mouse testicles and BTB permeability were observed using hematoxylin-eosin, Evans blue, and lanthanum nitrate as tracers. The expression of the BTB tight junction protein occludin was examined using real-time polymerase chain reaction and Western blotting.
At 1, 7, and 14 days after irradiation, the BTB structure was damaged, the BTB permeability was significantly increased, numerous apoptotic or necrotic spermatogenic cells were found in the lumen, and the mRNA and protein expression levels of occludin were markedly decreased. The BTB structure and occludin expression levels had gradually recovered by 21 and 28 days after irradiation.
Electromagnetic pulse irradiation damaged the structure and function of mouse BTB, resulting in apoptosis or necrosis of the spermatogenic cells.
Urology 07/2012; 80(1):225.e1-6. · 2.43 Impact Factor
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ABSTRACT: Background: Foreign body aspiration is a common life-threatening event in young children. Tracheobronchial foreign body removal is usually performed by rigid tracheobronchoscopy under general anesthesia. Anesthetic and ventilation techniques vary greatly among anesthesiologists and institutions. In the present retrospective study, we report our anesthetic experience over 5 years. We describe complications and outcomes and analyze the clinical characteristics of anesthesia and ventilation. Methods: We retrospectively reviewed relevant clinical findings of 586 pediatric patients treated with rigid tracheobronchoscopy under general anesthesia. All procedures were performed under inhaled sevoflurane anesthesia combined with remifentanil infusion, with spontaneous respiration assisted by high-frequency jet ventilation (HFJV) and topical airway anesthesia. Results: Among 586 patients, the foreign body was successfully removed by rigid tracheobronchoscopy in 558 patients, and no foreign body was found in 28 patients. Laryngospasm was observed during the procedure in five patients. Hypoxemia was observed in 15 patients (2.6%). No severe complications or deaths occurred. The mean operation time was 22 min and the average hospital stay was 2 days. Conclusion: Inhaled sevoflurane anesthesia combined with remifentanil infusion, with spontaneous respiration assisted by HFJV and topical airway anesthesia, is safe and effective for tracheobronchial foreign body removal.
Pediatric Anesthesia 05/2012; · 2.10 Impact Factor
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ABSTRACT: Previous studies have shown that regulation of the epidermal growth factor gene (EGFR) pathway plays a role in glioma progression. Certain genotypes of the EGFR gene may be related to increased glioblastoma risk, indicating that germ line EGFR polymorphisms may have implications in carcinogenesis. To examine whether and how variants in the EGFR gene contribute to glioma susceptibility, we evaluated nine tagging single-nucleotide polymorphisms (tSNPs) of the EGFR gene in a case-control study from Xi'an city of China (301 cases, 302 controls). EGFR SNP associations analyses were performed using SPSS 16.0 statistical packages, PLINK software, Haploview software package (version 4.2) and SHEsis software platform. We identified two susceptibility tSNPs in the EGFR gene that were potentially associated with an increased risk of glioma (rs730437, p = 0.016; OR: 1.32; 95%CI: 1.05-1.66 and rs1468727, p = 0.008; OR: 1.31; 95%CI: 1.04-1.65). However, after a strict Bonferroni correction analysis was applied, the significance level of the association between EGFR tSNPs and risk of glioma was attenuated. We observed a protective effect of haplotype "AATT" of the EGFR gene, which was associated with a 29% reduction in the risk of developing glioma, while haplotype "CGTC" increased the risk of developing glioma by 36%. Our results, combined with previous studies, suggested an association between the EGFR gene and glioma development.
PLoS ONE 01/2012; 7(5):e37531. · 4.09 Impact Factor
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Dong Sun,
Bing Wang,
Ming Shi,
Yun-Xia Zhang,
Lin-Fu Zhou,
Zhi-Rong Liu,
Zhong-Liang Wu,
Wen Jiang,
Jun-Liang Han, Li-Ze Xiong,
Gang Zhao
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ABSTRACT: Ginsenoside-Rd (GS-Rd) is one of the major active components of Panax ginseng, and was shown to have the protective effects against several insults. However, we still lack some basic knowledge of GS-Rd, including its pharmacokinetic, tissue distribution and excretion in vivo in experimental animal, such as mice and rats. In this study, HPLC and radioactive tracer assays were performed to determine pharmacokinetic, tissue distribution and excretion of GS-Rd in rodents. After intravascular administration with 20, 50 or 150 mg/kg GS-Rd, the dynamic changes of GS-Rd concentrations in plasma were consistent with a two-compartment model while the concentration of ³H-labeled GS-Rd was rapidly reached the peak in plasma, and distributed to various tissues, among which the highest concentration was observed in the lung.
Phytomedicine: international journal of phytotherapy and phytopharmacology 09/2011; 19(3-4):369-73. · 2.17 Impact Factor
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ABSTRACT: Treating bone cancer pain continues to be a clinical challenge and underlying mechanisms of bone cancer pain remain elusive. Here, we report that EphB1 receptor forward signaling in the spinal cord is critical to the development of bone cancer pain and morphine tolerance in treating bone cancer pain. Tibia bone cavity tumor cell implantation (TCI) produces bone cancer-related thermal hyperalgesia, mechanical allodynia, spontaneous and movement-evoked pain behaviors, and bone destruction. Production and persistence of these pain behaviors are well correlated with TCI-induced upregulation of EphB1 receptor and its ligand ephrinB2 in the dorsal horn and primary sensory neurons. Spinal administration of an EphB1 receptor blocking reagent EphB2-Fc prevents and reverses bone cancer pain behaviors and the associated induction of c-Fos and activation of astrocytes and microglial cells, NR1 and NR2B receptors, Src within the N-methyl-D-aspartate receptor complex, and the subsequent Ca(2+)-dependent signals. The exogenous ligand ephrinB2-Fc upregulates level of phosphorylation of NR1 and NR2B receptors depending on the activation of EphB1 receptor. Spinal administration of EphB2-Fc and ephrinB2-Fc induces downregulation of EphB1 and ephrinB2, respectively, accompanied with increased activity of matrix metalloproteinase (MMP)-2/9. Blocking MMP-2 or MMP-9 reverses EphB1-Fc treatment-induced downregulation of EphB1 receptor. In addition, spinal blocking or targeted mutation of EphB1 receptor reverses morphine tolerance in treating bone cancer pain in rats and defensive pain in mice. These findings show a critical mechanism underlying the pathogenesis of bone cancer pain and suggest a potential target for treating bone cancer pain and improving analgesic effect of morphine clinically.
Cancer Research 05/2011; 71(13):4392-402. · 7.86 Impact Factor
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ABSTRACT: To investigate the effect of hydrogen gas inhalation on survival rate and serum high mobility group box 1 (HMGB1) levels in severe septic mice.
Severe sepsis was induced by cecal ligation and puncture (CLP) operation in mice.A total of 248 mice were randomly divided into four groups: sham operation group (sham), sham operation with hydrogen gas inhalation group (sham+H2), severe CLP group (severe CLP) and severe CLP with hydrogen gas inhalation group (severe CLP+H2). Hydrogen gas inhalation was given for 1 h at 1st and 6th h after CLP or sham operation, respectively. The survival rates and serum HMGB1 levels of all groups at different time points were measured.
The 7-d survival rates of severe CLP mice was 0 % (Compared with Sham group, P <0.05), and the serum HMBG1 levels from h2 to h32 after CLP operation were significantly increased in severe CLP mice (Compared with Sham group, P <0.05). Hydrogen gas treatment increased the 7-d survival rate of severe CLP mice to 60 % (Compared with severe sepsis group, P <0.05) and significantly reduced the serum HMGB1 levels at different time points (Compared with severe sepsis group, P <0.05).
Hydrogen gas inhalation can decrease the serum HMGB1 levels and increase the survival rate of rats with severe sepsis.
Zhejiang da xue xue bao. Yi xue ban = Journal of Zhejiang University. Medical sciences 09/2010; 39(5):454-7.
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ABSTRACT: To investigate the effect of electroacupuncture preconditioning on the serum level of S100 calcium-binding protein beta (S100beta) and neuron-specific enolase (NSE) in patients undergoing craniocerebral tumor operation.
A total of 32 patients, who would go through craniocerebral tumor resection under general anesthesia, were randomly assigned to two groups, 16 in each group. Patients in the electroacupuncture (EA) group received electroacupuncture on Fengfu acupoint (Du16) and Fengchi acupoint (GB20) for 30 min, 2 h before operation. The stimulus is 1-4 mA with a density wave frequency of 2/15 Hz. Patients in the control group received no pretreatment. Anesthesia was maintained with remifentanil at the dose of 4-8 mg/kg per hour, pumped intravenous drip of vecuronium at 1.0-2.0 microg/kg each hour, and discontinuous intravenous dripped with vecuronium bromide at 0.5-1 mg. The serum levels of S100beta and NSE were measured with ELISA before operation, before skin incision, after tumor removal, at the end of operation, and at 24 h after operation.
The serum level of S100beta and NSE did not change before skin incision. The serum level of NSE increased significantly and the level of S100beta increased insignificantly after the tumor resection. The serum levels of S100beta and NSE in the EA group and the control group were 1.16+/-0.28 microg/L vs 1.47+/- 0.33 microg/L, 24.7+/-13.3 microg/L vs 31.4+/-14.1 microg/L at the end of the operation, respectively. Twenty-four h after operation, the correspondence indices were 1.18+/-0.31 microg/L vs 1.55+/-0.26 microg/L, and 25.5+/-12.4 microg/L vs 32.4+/- 11.7 microg/L. The two indices at these two time points were significantly increased than those before operation, respectively (P<0.05). At the end of the operation and 24 h post-operation, the serum levels of S100beta and NSE in the EA group were significantly lower than those in the control group (P<0.05).
Electroacupuncture Fengchi and Fengfu for 30 min before craniocerbral tumor operation could decrease the serum level of S100beta and NSE, thus may have potential protective effect on brain damage, which needs to be further studied.
Chinese Journal of Integrative Medicine 06/2010; 16(3):229-33. · 0.80 Impact Factor
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ABSTRACT: Vascular hyporeactivity, which occurs in the terminal stage of hemorrhagic shock, is believed to be critical for treating hemorrhagic shock. The present study was designed to examine whether the CB1 cannabinoid receptor (CB1R) was involved in the development of vascular hyporeactivity in rats suffering from hemorrhagic shock.
Sixteen animals were randomly divided into two groups (n = 8 in each group): sham-operated (Sham) and hemorrhagic shock (HS) groups. Hemorrhagic shock was induced by bleeding. The mean arterial pressure (MAP) was reduced to and stabilized at (25 +/- 5) mmHg for 2 hours. The vascular reactivity was determined by the response of MAP to norepinephrine (NE). In later experiments another twelve animals were used in which the changes of CB1R mRNA and protein in aorta and superior mesenteric artery (SMA) were analyzed by RT-PCR and Western blotting. In addition, we investigated the effects of a CB1R antagonist on the vascular hyporeactivity and survival rates in rats with hemorrhagic shock. Survival rates were analyzed by the Fisher's exact probability test. The MAP response was analyzed by one-way analysis of variance (ANOVA).
Vascular hyporeactivity developed in all animals suffering from hemorrhagic shock. The expression of CB1R mRNA and protein in aorta and 2 - 3 branches of the SMA were significantly increased in the HS group after the development of vascular hyporeactivity when compared to those in Sham group. When SR141716A or AM251 was administered, the MAP response to NE was (41.75 +/- 4.08) mmHg or (44.78 +/- 1.80) mmHg respectively, which was higher than that in saline groups with (4.31 +/- 0.36) mmHg (P < 0.01). We also showed an increased 4-hour survival rate in the SR141716A or AM251-treated group with 20% or 30%, but with a statistically significant difference present between the AM251-treated and saline groups (P < 0.05).
CB1R is involved in vascular hyporeactivity resulting from hemorrhagic shock in rats, and CB1R antagonist may be useful in treating patients with traumatic, hemorrhagic shock who need field-rescue or initial treatment.
Chinese medical journal 04/2009; 122(8):950-4. · 0.86 Impact Factor
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ABSTRACT: Sepsis is a leading cause of death in the intensive care units. The late inflammatory cytokine, high-mobility group box 1 (HMGB1), plays a critical role in sepsis. In the present study, we investigated the association between the serum HMGB1 levels and the severity of organ injury in the lipopolysaccharide-induced sepsis in rats.
To produce an animal model of sepsis with different degree of organ injury, animals were treated with three different doses of lipopolysaccharide (4, 8 and 16 mg/kg), and the animals in control group were treated with the same volume of the vehicle (saline). The levels of serum HMGB1 were measured at 0, 2, 4, 8, 16, 24, 32 and 48 hours after lipopolysaccharide (LPS) or vehicle injection, meanwhile the biochemical and histopathological indicators for the severity of organ injury were assessed.
The level of HMGB1 had a positive, high correlation with the abnormal changes of serum cardiac troponin I, alanine aminotransferase, aspartate aminotransferase, creatinine and blood urea nitrogen, as well as the pathologic scores of heart, lung, liver and kidney.
The level of serum HMGB1 is highly correlated with the severity of sepsis in rats, suggesting that HMGB1 could serve as a valuable adjunct in the diagnosis and management of sepsis.
Chinese medical journal 03/2009; 122(4):449-54. · 0.86 Impact Factor
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ABSTRACT: This study investigates the effects of electroacupuncture (EA) preconditioning on blood-brain barrier (BBB) integrity and matrix metalloproteinase-9 (MMP-9) expression in subsequent ischemic hemisphere.
Focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) in rats. Animals were randomly divided into four groups: normal, sham-operated, MCAO and EA groups. In EA group, rats received electroacupuncture stimuli at the Baihui acupoint (GV 20) 30 minutes/day for 5 days. Twenty-four hours after last treatment, the MCAO was performed. The brain water content and BBB permeability were measured 24 hours after MCAO. MMP-9 expression and activity were measured at 6, 12 and 24 hours after MCAO.
The results showed that the brain water content of ischemic hemisphere was lower in EA group (81.45 +/- 1.09%) compared with MCAO group (83.98 +/- 1.30%; p<0.05). Similarly, the Evans blue content in EA group (4.90 +/- 1.77 microg/g) was lower compared with MCAO group (9.41 +/- 2.87 microg/g; p<0.05). The protein expression and enzyme activity of MMP-9 increased and reached maximum at 24 hours after reperfusion. However, the protein expression was lower in EA group at 12 and 24 hours after reperfusion (p<0.01, versus MCAO group), and enzyme activity was lower in EA group only at 24 hours (p<0.01, versus MCAO group).
EA preconditioning could attenuate brain edema and BBB disruption caused by subsequent cerebral ischemia. EA preconditioning could decrease MMP-9 expression and activity, which may be an important mechanism of cerebral ischemic tolerance.
Neurological Research 03/2009; 31(8):853-8. · 1.52 Impact Factor
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ABSTRACT: The neuroprotective effect of the cyclooxygenase (COX) inhibitor has been demonstrated in acute and chronic neurodegenerative processes. But its function under cerebral ischemic conditions is unclear. This study was designed to evaluate the neuroprotective efficacy of emulsified flurbiprofen axetil (FA, COX inhibitor) and its therapeutic time window in a model of transient middle cerebral artery occlusion (MCAO) in rats.
Forty-eight male SD rats were randomly assigned into six groups (n = 8 in each group); three FA groups, vehicle, sham and ischemia/reperfusion (I/R) groups. Three doses of FA (5, 10 or 20 mg/kg, intravenous infusion) were administered just after cerebral ischemia/reperfusion (I/R). The degree of neurological outcome was measured by the neurologic deficit score (NDS) at 24, 48 and 72 hours after I/R. Mean brain infarct volume percentage (MBIVP) was determined with 2, 3, 5-triphenyltetrazolium chloride (TTC) staining at 72 hours after I/R. In three other groups (n = 8 in each group), the selected dosage of 10 mg/kg was administrated intravenously at 6, 12 and 24 hours after I/R.
The three different doses of FA improved NDS at 24, 48 and 72 hours after I/R and significantly reduced MBIVP. However, the degree of MBIVP in the FA 20 mg/kg group differed from that in FA 10 mg/kg group. Of interest is the finding that the neuroprotective effect conferred by 10 mg/kg of FA was also observed when treatment was delayed until 12 - 24 hours after ischemia reperfusion.
COX inhibitor FA is a promising therapeutic strategy for cerebral ischemia and its therapeutic time window could last for 12 - 24 hours after cerebral ischemia reperfusion, which would help in lessening the initial ischemic brain damage.
Chinese medical journal 01/2009; 121(24):2572-7. · 0.86 Impact Factor
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ABSTRACT: To investigate the neuroprotective effects and dose-response relation by combining JAK-STAT signal pathway inhibitor (AG490) with free radical scavenger dimethylthiourea (DMTU) in rats subjected to focal cerebral ischemia/reperfusion (I/R) injury.
In all rats, the middle cerebral artery occlusion (MCAO) was produced by occlusion of right internal carotid artery with a nylon monofilament. One hundred male Sprague-Dawley (SD) rats were divided into ten groups according to random digits table, 10 rats were in each group. The first experiment involved I/R model control, dimethyl sulfoxide (DMSO) control, normal saline (NS) control, AG490, DMTU and combination of AG490 and DMTU (A+D) groups. The second experiment involved model group and three experimental groups in which various doses of DMTU and AG490 were administered. The neurological behavior scores (NBS) were assessed at 24, 48 and 72 hours after reperfusion respectively in both experiments, and all the animals were then decapitated to determine the brain infarct volume after 72 hours.
The values of NBS in A+D group, AG490 group and DMTU group were higher than those in model group at 24, 48 and 72 hours after I/R, and their brain infarct volumes were obviously smaller than model group as well (all P<0.05). The brain infarct volume in A+D group was obviously smaller compared with AG490 and DMTU alone (all P<0.05). The values of NBS were higher and the brain infarct volumes were smaller in both high dose and medium dose combination groups than those in low dose combination and model groups respectively (all P<0.05). In addition, brain infarct volumes in high dose group were smaller than medium dose group (P<0.05), but there was no statistically significant difference between low dose and model groups.
The combined application of AG490 and DMTU produces a dose-dependent synergistic neuroprotective effect.
Zhongguo wei zhong bing ji jiu yi xue = Chinese critical care medicine = Zhongguo weizhongbing jijiuyixue 11/2008; 20(11):641-4.
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ABSTRACT: China is a developing country with a population over 1.3 billion with the second largest group of people in poverty next to India. There are about 159 million motor vehicles, with 163,887,372 drivers. From 2001 to 2004 over 100,000 people died each year in traffic accidents. With law enforcement and public education, traffic accidents have decreased, and the death rate is now less than 100,000 each year.
Clinical Orthopaedics and Related Research 10/2008; 466(10):2329-36. · 2.53 Impact Factor
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ABSTRACT: The purpose of this study was to explore the therapeutic time window and mechanism of tetramethylpyrazine on transient focal cerebral ischemia/reperfusion injury. Middle cerebral artery occlusion was conducted in male Sprague-Dawley rats and 20mg/kg tetramethylpyrazine was injected intraperitoneally at different time points. Neurological deficit scores and brain infarction volumes were measured 72 h after reperfusion started. The expression of thioredoxin and thioredoxin reductase were examined at 6h and at 24h after reperfusion. Our results included the findings of a significant reduction in neurological deficit scores and infarction volume in the treatment group as compared to the control group. Ischemia/reperfusion injury resulted in a decrease in the expression of thioredoxin, while tetramethylpyrazine administration greatly elevated the expression of thioredoxin-1/thioredoxin-2 mRNA and thioredoxin reductase-1/thioredoxin reductase-2 mRNA. These findings suggest that administration of tetramethylpyrazine, within a 4h time period post-transient focal stroke, may reduce cerebral ischemic reperfusion damage. Moreover, the neuroprotective effect of tetramethylpyrazine may be mediated, in part, by an increase in genetic transcription of thioredoxin.
Neuroscience Letters 10/2008; 449(1):24-7. · 2.11 Impact Factor
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ABSTRACT: 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.
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.
(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).
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.
Zhonghua yi xue za zhi 08/2008; 88(33):2355-9.
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ABSTRACT: 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.
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.
(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).
Our study demonstrates that sevoflurane postconditioning against spinal cord ischemia injury via the release of oxygen free radicals in rabbits.
Zhonghua yi xue za zhi 08/2008; 88(27):1916-20.
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ABSTRACT: To investigate the neuroprotective effect of preconditioning with cannabinoid (CB) receptor agonist WIN 55, 212 - 2 on focal cerebral ischemia.
Fifty male SD rats were randomly assigned to 5 equal groups: control group undergoing middle cerebral artery occlusion (MCAO) for 2 h only without any preconditioning; 3 WIN 55, 212 - 2 preconditioning groups (WIN1-3) injected intraperitoneally with WIN 55, 212 - 2 at the doses of 0.3, 1, and 3 mg/kg respectively 24 h before MCAO for 2 h, and DMSO group injected intraperitoneally with dimethyl sulfoxide (DMSO), solvent of WIN 55, 212 - 2 24 h before MCAO for 2 h. 24, 48, and 72 hours after reperfusion the neurological function score (NFS) was evaluated the rats were then decapitated with their brains taken out. Brain infarct volume was evaluated with 2% 2, 3, 5-triphenyltetrazolium chloride (TTC) staining.
The NFS values of the rats in WIN 55, 212 - 2 preconditioning groups were all significantly higher than those of the control and DMSO groups (all P < 0.05) while the infarct volumes of the WIN 55, 212 - 2 preconditioning groups were all significantly smaller than those of the control and DMSO groups (all P < 0.05) 24, 48, and 72 h after reperfusion. The infarct volumes of the WIN2 and WIN3 groups were both significantly smaller than that of the WIN1 group (both P < 0.05). However, there was no significant difference in the infarct volume between WIN2 and WIN3 groups (P = 0.928).
WIN 55, 212 - 2 preconditioning has neuroprotective effect on focal cerebral ischemia with a dose-dependent manner.
Zhonghua yi xue za zhi 08/2008; 88(31):2219-22.
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ABSTRACT: EphrinB-EphB receptor signaling plays diverse roles during development, but recently has been implicated in synaptic plasticity in the matured nervous system and in pain processes. The present study investigated the correlation between expression of ephrinB and EphB receptor proteins and chronic constriction injury (CCI) of the sciatic nerve and dorsal rhizotomy (DR) in dorsal root ganglion (DRG) and spinal cord (SC); and interaction of CCI and DR on expression of these signals. Adult, male Sprague-Dawley rats were employed and thermal sensitivity was determined in the sham operated CCI and DR rats. Western blot and immunobiochemistry analysis and immunofluorescence staining techniques were used to detect the expression and location of the ephrinB-EphB receptor proteins in DRG and SC. The results showed that expression of ephrinB1 and EphB1 receptor proteins was significantly upregulated in DRG and SC in a time-dependent manner corresponding to the development of thermal hyperalgesia after CCI. The increased expression is predominately located in the medium- and small-sized DRG neurons, the superficial layers of spinal dorsal horn (DH) neurons, and the IB4 positive nociceptive terminals. DR increases ephrinB1 in DRG, not SC and EphB receptor in SC, not DRG. DR suppressed CCI-induced upregulation of ephrinB1 in SC and EphB1 receptor in DRG and SC. These findings indicate that ephrinB-EphB receptor activation and redistribution in DRG and DH neurons after nerve injury could contribute to neuropathic pain. This study may also provide a new mechanism underlying DR-induced analgesia in clinic.
European journal of pain (London, England) 04/2008; 12(8):1031-9. · 3.37 Impact Factor
