Objective To investigate the effect of melatonin on mice with ischemia-reperfusion via a silent information regulator 1 (SIRT1) reducing mitochondrial oxidative stress mechanism. Methods A transient middle cerebral artery occlusion ( MCAO) cerebral ischemia-reperfusion ( IR) model in mice was established by the suture-occluded method. One hundred and ninety mice were injected with melatonin intraperitoneally or the SIRT1 inhibitor (EX527) intracerebroventricularly,30 dead and model failure mice were excluded. They were divided into IR,melatonin,melatonin +EX527,and EX527 groups (n =40 in each group ) according to the random number table. The cerebral infarct volume was detected by the triphenyltetrazolium chloride (TTC) method,the brain edema was measured by the wet and dry weight method and the neurological deficit scores were measured. Western blot was used to detect SIRT1,Ac-P53, acetylated-nuclear factorκB (Ac-NF-κB),BCl2,Bax proteins in the mitochondria and cytoplasm,as well as the cytochrome C protein expression. A single factor analysis of variance was used for comparison among the groups. Results ( 1 ) There were significant differences in cerebral infarction volume, neurological dysfunction scores and cerebral edema among the four groups ( F values,16. 452,23. 622,and 18. 786, respectively (all P<0. 05). There were significant differences in the expression levels of SIRT1,Ac-P53, Ac-NF-κB,BCl2, and Bax among the four groups ( F values, 2348. 158, 1434. 841, 7042. 563, 14627. 128,and 691. 475,respectively,all P<0. 05). There were significant differences in mitochondrial membrane potential,mitochondrial reactive oxygen species,and complex I activity in mice among the four groups (F value,28. 454,33. 728 and 29. 716,respectively,all P <0. 05). (2) Compared with the IR group,the infarct volume was reduced (32 ± 5 mm3 vs. 57 ± 5 mm3,P<0. 05),neurological deficit scores were decreased (2. 4 ± 0. 3 vs. 3. 5 ± 0. 3,P<0. 05);brain edema was reduced (80. 2 ± 0. 9% vs. 83. 9 ± 1. 2%,P<0. 05);the expression levels of SIRT1 and anti-apoptosis protein BCL2 were increased in the melatonin group (P<0. 05);the expression levels of pro-apoptotic protein BAX and Ac-P53,Ac-NF-κB were reduced ( P <0. 05 );the mitochondrial membrane potential, mitochondrial complex I activity and cytochrome C level were increased (P<0. 05);and the cytoplasmic reactive oxygen species and cytochrome C level were decreased (P < 0. 05). (3) Compared with the melatonin group,cerebral infarction volume were increased (42 ± 5 mm3 vs. 32 ± 5 mm3,P < 0. 05);nerve dysfunction scores were increased(3. 2 ± 0. 3 vs. 2. 4 ± 0. 3,P<0. 05);cerebral edema was aggravated (83. 4 ± 0. 8% vs. 80. 2 ± 0. 9%, P < 0. 05 );the expression levels of SIRT1 and anti-apoptotic protein BCL2 were reduced (P <0. 05);the pro-apoptotic protein BAX,Ac-P53,and Ac-NF-κB expression levels were increased (P<0. 05);the mitochondrial membrane potential and mitochondrial complex I activity and cytochrome C level were decreased (P<0. 05);and the cytoplasmic reactive oxygen species and cytoplasmic cytochrome C level were increased in the melatonin+EX527 group (P<0. 05). Conclusion In ischemic stroke model mice, melatonin plays a neuroprotective role by activating the SIRT1 signaling pathway and reducing oxidative stress injury and cell death in mitochondria,thus plays a role in cerebral protection.

Objective:To investigate the effects of melatonin(MLT)on hypothalamic-pituitary-adrenal(HPA)axis in posttraumatic stress disorder(PTSD)rats induced by foot shocks.Methods:The rat model of PTSD was prepared by plantar electroshock,and MLT was given by intraperitoneal injection.The behavioral changes of rats were detected by rejection reaction test,the mRNA expression of corticotropin-releasing hormone(CRH)in hypothalamus was detected by real time RT-PCR,and the contents of adrenocorticotropin hormone(ACTH),epinephrine(EPI)and glucocorticoid(GC)in serum were detected by enzyme-linked immunosorbent assay(ELISA).Results:In the PTSD group,the rejection reaction was obvious,the expression of CRH mRNA in hypothalamus was increased(P＜0.05),the serum ACTH and EPI were increased(P＜0.05),but the GC level was decreased(P＜0.05).After MLT treatment,the rejection reaction of PTSD rats was significantly alleviated,CRH mRNA expression in hypothalamus was decreased(P＜0.05),serum ACTH and EPI levels were decreased(P＜0.05),and GC levels were increased(P＜0.05).Conclusion:MLT treatment can relieve the symptoms of PTSD and restore the neuroendocrine balance of HPA axis in rats.

Objective:To study the role of DDX3X/NF-κB pathway in early neuronal apoptosis in subarachnoid hemorrhage(SAH)mice.Methods:The mouse model of SAH was established by internal carotid artery puncture,and the neurological function score of the mice was evaluated.The DDX3X expression was knocked down using recombinant lentivirus expressing DDX3X targeted shRNA(Lv-shDDX3X),or the NF-κB pathway was inhibited by NF-κB-IN-1(IN-1).Western Blot was used to detect the expression of DDX3X and NF-κB(p65)in mouse cortex.TUNEL/NeuN staining was used to detect the apoptosis of cerebral cortex neurons.Results:Twenty-four hours after SAH operation,the neurological function of mice was significantly impaired(P＜0.05).While the expression of DDX3X was signifi-cantly increased and the expression of NF-κB(p65)was significantly decreased in the cortex(P＜0.05).When the DDX3X expression is knocked down firstly,then SAH surgery is performed.The neurological function of mice was sig-nificantly recovered,and the expression of NF-κB(p65)protein was significantly higher than that in SAH group(P＜0.05);If the NF-κB activity was inhibited by IN-1 while DDX3X knockdown,there is no significant recovery of neuro-logical function in SAH mice.TUNEL/NeuN staining showed that the number of TUNEL-positive neurons in the brain tissue after DDX3X knockdown was less than that in the SAH group(P＜0.05),while the number of TUNEL-positive neurons was not significantly reduced when IN-1 was used to inhibit NF-κB activity at the same time of DDX3X knock-down.Conclusion:DDX3X/NF-κB mediated cell death in mice with early brain injury after SAH.

OBJECTIVETo explore prospective diagnostic criteria for preleukemia.

METHODSA case control study was done comparing the discrepancies on clinical and laboratory features between patients with preleukemia and those with chronic aplastic anemia (CAA) or atypical paroxysmal nocturnal hemoglubinuria (a-PNH).

RESULTSThere were eight variables of significance: (1) lymphocytoid micromegakaryocytes in the bone marrow; (2) immature granulocytes in the peripheral blood; (3) > or = 2.0% myeloblasts in the bone marrow; (4) positive periodic acid schiff (PAS) stained nucleated erythrocytes; (5) myeloid differentiation index > or = 1.8; (6) typical colonal karyotypic abnormalities; (7) negative sister chromatid differentiation; (8) cluster/colony ratio of granulocyte-macrophage colony-forming units (CFU-GM) > 4.0. The following criteria were assigned: A: to meet variable one and at least two of the other seven variables and B: to meet at least four of the eight variables. All of the patients with preleukemia met either A or B and none of the patients with CAA or a-PNH did.

CONCLUSIONSPreleukemia is different from CAA or a-PNH. It has its own clinical and laboratory features, which may be useful for its prospective diagnosis.

Adolescent ; Adult ; Aged ; Apoptosis ; Case-Control Studies ; Chromosome Aberrations ; Female ; Humans ; Immunophenotyping ; Male ; Middle Aged ; Preleukemia ; diagnosis ; genetics ; pathology ; Survival Rate