Objective To investigate the effects of adenosine 2A receptor (A2AR) activation on oxidative stress in small-forsize liver transplantation. Methods A rat orthotopic liver transplantation model was performed using 40% graft, 18 recipients were given intravenously saline (control group), CGS21680 (A2AR agonist, CGS21680 group) or ZM241385 (A2AR antagonist, CGS21680+ZM241385 group) randomly. Aspartate aminotransferase (AST), enzymatic antioxidants 〔superoxide dismutase (SOD); catalase (CAT); glutathione peroxidase (GSH-Px)〕, non-enzymatic antioxidants 〔ascorbic acid (AA); glutathione (GSH); α-tocopherol (TOC)〕 and lipid oxidant metabolites malondialdehyde (MDA) were measured and analyzed at 6 h after reperfusion. Results Compared with the control group and CGS21680+ZM241385 group, A2AR activation increased the activities of SOD and GSHPx (Plt;0.05), reduced the productions of AST and MDA (Plt;0.05), increased the levels of AA, GSH and TOC (Plt;0.05) in CGS21680 group. But there was no significant change in CAT activity (Pgt;0.05) among 3 groups. Conclusions A2AR activation improves the antioxidant enzyme activities, promotes the production of antioxidants, and slowes down the increase in MDA level, depresses of the increase in AST activity. A2AR activation suppresses oxidative damage and increases the antioxidant capacity which in turn minimizes their harmful effects of ischemia-reperfusion in small-for-size liver transplantation.
Objective To evaluate the inhibiting effect of adenosine on rat retinal ganglion cells (RGC) death induced by P2X7 and N-methyl-D-aspartate (NMDA) receptor. Methods (1) Long-Evan neonatal rats were back labeled with aminostilbamidine to identify RGC. The viability of RGC affected by P2X7 excitomotor BzATP (50 mu;mol/L), glutamate receptor excitomotor NMDA (100 mu;mol/L) and adenosine (300 mu;mol/L) was detected. (2) RGC from the retinae of unlabeled neonatal rats were cultured in vitro. After labeled with Fura-2 methyl acetate, an intracellular calcium indicator, the effect of BzATP, NMDA and adenosine on intracellular Ca2+ level was detected byCa2+ imaging system. Results Both BzATP (50 mu;mol/L) and NMDA(100 mu;mol/L) could kill about 30% of the RGC. Cell death was prevented by adenosine (300 mu;mol/L) with the cell viability increased from (68.9plusmn;2.3)% and (69.9plusmn;3.2)% to (91.2plusmn;3.5)% (P＜0.001) and (102.1plusmn;3.9)% (P＜0.001), respectively. BzATP (50 mu;mol/L) led to a large, sustained increase of intracellular Ca2+ concentration to (1183plusmn;109) nmol/L. After the adenosine intervened, Ca2+ concentration increased slightly to (314plusmn;64) nmol/L (P＜0.001). Conclusion Adenosine may prevent RGC death and increase of intracellular Ca2+ concentration from P2X7and NMDA receptor stimulation. (Chin J Ocul Fundus Dis, 2007, 23: 133-136)
Objective To study the effects of adenosine 2A receptor activation on activation, proliferation, and toxicity of T lymphocytes stimulated by phytohemagglutinin (PHA) in vitro. Methods A model of activated T cells was established by stimulating the cells with PHA. Those T cells were treated with different concentrations of adenosine 2A receptors agonist (0.01 μmol/L, 0.1 μmol/L, 1 μmol/L, and 10 μmol/L CGS21680). The expressions of CD69, CD25 and proliferation of T cells were measured by fluorescent antibody stain and flow cytometry. ELISA method was used to detect IL-2 and INF-γ levels. Results All concentrations of CGS21680 significantly inhibited the expressions of CD25 and CD69 on PHA-stimulated T cells surface and proliferation of T cells （Plt;0.05， Plt;0.01）. IL-2 and INF-γ secreted by T cells were significantly suppressed, too （Plt;0.01）. Conclusion Activation of adenosine 2A receptor can effectively inhibit the activation, proliferation, and toxicity of T cells in vitro.
Epilepsy is a complex disease spectrum, because of long-term recurrent seizures and seriously affect the quality of life of patients, it is of great significance to explore the pathogenesis of epilepsy and actively seek new therapeutic targets. In this paper, the pathogenesis of epilepsy related to mitochondrial pathway was discussed from the aspects of energy depletion, oxidative stress damage, impaired calcium homeostasis, increased glutamic acid release, mitochondrial DNA mutation, Coenzyme Q10 deficiency, abnormal mitochondrial movement and change, and relevant therapeutic ideas were proposed. This paper shows that mitochondrial function affects the onset of epilepsy from various ways. Further understanding of the relationship between mitochondria and the onset of epilepsy is beneficial to find new therapeutic targets and develop new therapies beyond the control of epilepsy.
ObjectiveTo explore the relationship between mitochondrial function and the severity of sepsis by detecting the platelet mitochondrial permeability transition pore, transmembrane potential and adenosine triphosphate (ATP) levels in peripheral blood. MethodsAccording to random number table, 40 male SD rats were randomly divided into three sepsis model groups (group A, B and C) and a sham group (group D). The rats in the model groups received cecal ligation and puncture (CLP) treatment with different percent of ligated length in total length of the cecum (10% in group A, 30% in group B and 50% in group C, respectively). Twenty-four hours later, peripheral blood was collected for TNF-α, IL-1βand IL-6 levels determination, also the mitochondrial permeability transition pore, transmembrane potential and ATP content were tested in the isolated platelet. One-way ANOVA test was used to determine the relevance between above indices and the severity of sepsis. Meanwhile, 29 patients with sepsis were enrolled for clinical study. After APACHEⅡscoring, platelet samples of peripheral blood in the patients were collected for mitochondrial function determination. The relationship between mitonchondrial function and APACHEⅡscore was analyzed by Spearman method. ResultsCalcein fluorescence, membrane potential and ATP synthesis in platelet mitochondria of the rat sepsis model were gradually decreased with the increased severity of CLP, and the difference among these groups were all statistically significant (all P < 0.05). In clinical specimens, APACHEⅡscore was negatively correlated with ATP level of platelet mitochondria(r=-0.895, P < 0.05). ConclusionMitochondrial function of platelet in peripheral blood can be used as an effective indicator for the severity of sepsis.
The aim of this study is to assess ischemia/reperfusion injury in carbon tetrachloride induced cirrhotic liver as compared to normal liver in the rats. Results showed that in cirrhotic liver, instead of diminishing the hepatic vein nitric oxide level increased significantly after ischemia from 8.04 μmol/L to 11.52 μmol/L and remained high till 5 hrs after reperfusion. The hepatic adenosine triphosphate (ATP) contents decreased as that seen in normal rat but did not restore to normal till the end of 5 hrs after reperfusion. Based on these findings, it is postulated that in cirrhotic liver, ischemia/reperfusion injury is aggrvated as evidenced by of nitric oxide, and extended diminishing in ATP.
Objective To study the distribution of P2 Y2 receptor in spine cord, dorsal root ganglia and sciatic nerve in rat, and to provide the basis for clarifying the mechanism of the effect of adenosine triphosphate(ATP) on the peripheral nerve regeneration. Methods Six specimens of the spine cord, dorsal root ganglia and sciatic nerve from SD rats were fixed rapidly in 4% paraformaldehyde which included DEPC, imbedded by paraffin and made into ultrathin section. According to the sequence of P2 Y2 receptor’s gene, DNA needle was adopted to detect the distribution of P2 Y2 receptor by hybridization technique in section under the light microscope after theyhad been stained in NBT liquid（50 mg/ml） and BCIP liquid （75 mg/ml）. In thecontrol group, the ultrathin section was only covered with hybridism buffer solution. The result of staining was observed. ResultsHybridization in section showed that P2 Y2 receptor was distributed mainly in the anterior horn cell of spine cordgray matter and Schwann cell of the dorsal root ganglia. No P2 Y2 receptor was observed in the sciatic nerve of both groups. Conclusion P2 Y2 receptor is located mainly in the spine cord and the dorsal root ganglia. Extracellular ATP can affect the cell of spine cord, dorsal root ganglia through P2 Y2 receptor.
Objective To investigate the effect of adiponectin on proliferation of airway smooth muscle cells( ASMCs) , and explore its possible mechanism. Methods ASMCs were derived fromrat airway tissue and were cultured in vitro. RT-PCR was used to verify the expression of adiponectin receptors on ASMCs. Then ASMCs were treated with adiponectin at different concentrations( 5, 10, 20, 40, 80 μg/mL) for different periods of time( 1, 12, 24, 48, 72 hours) , respectively. The absorbsence ratios of adiponectin at different concentrations were determined by MTT assay. The adenosine monophosphate-activated protein kinase( AMPK) and phosphorylated AMPK( pho-AMPK) in ASMCs were quantified by Western blot after being treated with adiponectin at different concentrations ( 5, 10, 20, 40 μg/mL) for 48 hours. ResultsThe inhibition of adiponectin on ASMCs was showed in dose-dependent manner( r = 0. 324, P lt; 0. 01) and time-dependent manner( r = 0. 607, P lt; 0. 05) . Western blot indicated that the expression of pho-AMPK increased with the increased concentrations of adiponectin( r =0. 607, P lt; 0. 01) . The ratio of pho-AMPK/AMPK were ( 27. 66 ±1. 03) % , ( 31. 91 ±0. 86 ) %, ( 75. 52 ±2. 67) % , and ( 84. 50 ±1. 05) % ,respectively, with significant differences between each concentrations of adiponectin( P lt; 0. 05) . There was no expression of pho-AMPK in the control group. Conclusion Adiponectin can significantly inhibit ASMCs’proliferation by activating AMPK.
Objective To evaluate the clinical value and safety of adenosine monophosphate( AMP)bronchoprovocation test in patients with asthma. Methods Sixty asthmatics, including 19 cases with uncontrolled asthma, 22 with partially controlled asthma, and 19 with controlled asthma were enrolled. Twenty-four healthy volunteers were enrolled as control and 20 patients with upper respiratory tract infection ( URI) were also included. AMP bronchoprovocation test ( AMP-BPT) was performed. PD20 FEV1-AMP lt;40 mg was set as a cut-off value of positive response to AMP. Positive rate, sensitivity, specificity, accuracy and adverse reactions of AMP-BPT were evaluated. Eleven cases with uncontrolled asthma and 12 cases with partially controlled asthma were followed up with AMP-BPT three months and six months after inhaledcorticosteroids treatment. Asthma symptom scores were recorded a week early before each challenge. The correlation between PD20FEV1 -AMP and asthma symptom score was analyzed. Values of PD20 FEV1 -AMP were represented as median and quartile range [ M( QR) ] . Results No positive responses to AMP were found in both healthy and URI subjects. On the other hand, positive responses to AMP were found in all the uncontrolled asthmatics ( 100% ) with PD20FEV1 -AMP as 0. 6 mg ( 0. 4 mg) , in 19 partially controlled asthmatics ( 86. 4% ) with PD20 FEV1 -AMP as 5. 38 mg ( 32. 67 mg ) , and in 5 controlled asthmatics( 26. 3% ) with PD20FEV1 -AMP as 40 mg ( 29. 3 mg) . There were negative correlations between the logarithms of PD20 FEV1 -AMP and logarithms of asthma symptom scores ( r = - 0. 598, P lt; 0. 01) . The sensitivity, specificity and accuracy was 72% , 100%, and 84% , respectively. Percentage of subjects who experienced wheezing, cough, dyspnea, swallows stimulation, chest tightness, expectoration and cyanosis during AMP-BPT were 37. 5%, 21. 2%, 15. 4%,7. 7%, 7. 7%, 4. 8%, and 1. 0%, respectively. No severe adverse reaction was found. Conclusions AMP-BPT is helpful to the diagnosis and differential diagnosis of bronchial asthma. It also can be used to evaluate the severity and control level, and to monitor the therapeutic efficacy in clinical practice. Moreover, AMP-BPT is well tolerated with little adverse reaction.
Abstract： Objective To investigate the protective effects of adenosine (ADO) on lung ischemia/reperfusion injury following heart-lung transplantation in canine. Methods Canine heart-lung transplantation was performed．Canines were divided into two groups: transplant control groupand ADO group. The changes of arterial partial pressure of oxygen(PaO2) after reperfusion in two groups at 30，60，90，120 min were observed．The tissue contents of nitric oxide (NO) were measured at 10 min before ischemia, 10 min and 120 min after ischemia; 10 min and 60 min after reperfusion．The lung tissue samples were obtained 1h after reperfusion．The tissue myeloperoxidase(MPO) activity,content of malondialdehyde(MDA), content of superoxide dismutase(SOD), wet/dry ratio of lung(W/D) were measured.Microscopic examination of lungs was also conducted. Results (1)In ADO group，PaO2 were significantly higher than that in control group at 30，60，90 and 120 min after reperfusion (Plt;0.05)．(2) The tissue contents of NO at 120 min after ischemia, 10 min and 60 min after reperfusion were significantly lower than that at 10 min before ischemia(Plt;0.05). In ADO group，the tissue contents of NO at 120 min after ischemia, 10 min and 60 min after reperfusion were higher than that in control group respectively(Plt;0.05). (3)The tissue MPO activity, content of MDA, W/D in ADO group were significantly lower than those in corresponding control group. The content of SOD in ADO group were higher than that in control group(Plt;0. 05)．(4)The microscopic examination showed that there were severe leukocyte infiltration and edema formation in the alveolar space in control group, but the changes were less severe in ADO group. Conclusion Administration of ADO in canine heart-lung transplantation can protect the donor lung against ischemia／reperfusion injury．