Blockade of HCN2 Channels Provides Neuroprotection Against Ischemic Injury via Accelerating Autophagic Degradation in Hippocampal Neurons / 神经科学通报·英文版

In the central nervous system, hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are essential to maintain normal neuronal function. Recent studies have shown that HCN channels may be involved in the pathological process of ischemic brain injury, but the mechanisms remain unclear. Autophagy is activated in cerebral ischemia, but its role in cell death/survival remains controversial. In this study, our results showed that the HCN channel blocker ZD7288 remarkably decreased the percentage of apoptotic neurons and corrected the excessive autophagy induced by oxygen-glucose deprivation followed by reperfusion (OGD/R) in hippocampal HT22 neurons. Furthermore, in the OGD/R group, p-mTOR, p-ULK1 (Ser), and p62 were significantly decreased, while p-ULK1 (Ser), atg5, and beclin1 were remarkably increased. ZD7288 did not change the expression of p-ULK1 (Ser), ULK1 (Ser), p62, Beclin1, and atg5, which are involved in regulating autophagosome formation. Besides, we found that OGD/R induced a significant increase in Cathepsin D expression, but not LAMP-1. Treatment with ZD7288 at 10 μmol/L in the OGD/R group did not change the expression of cathepsin D and LAMP-1. However, chloroquine (CQ), which decreases autophagosome-lysosome fusion, eliminated the correction of excessive autophagy and neuroprotection by ZD7288. Besides, shRNA knockdown of HCN2 channels significantly reduced the accumulation of LC3-II and increased neuron survival in the OGD/R and transient global cerebral ischemia (TGCI) models, and CQ also eliminated the effects of HCN2-shRNA. Furthermore, we found that the percentage of LC3-positive puncta that co-localized with LAMP-1-positive lysosomes decreased in Con-shRNA-transfected HT22 neurons exposed to OGD/R or CQ. In HCN2-shRNA-transfected HT22 neurons, the percentage of LC3-positive puncta that co-localized with LAMP-1-positive lysosomes increased under OGD/R; however, the percentage was significantly decreased by the addition of CQ to HCN2-shRNA-transfected HT22 neurons. The present results demonstrated that blockade of HCN2 channels provides neuroprotection against OGD/R and TGCI by accelerating autophagic degradation attributable to the promotion of autophagosome and lysosome fusion.

Antitumor effect of allicin on esophageal cancer EC109 cells compared with chemotherapeutics in vitro / 中国病理生理杂志

AIM:To investigate the inhibitory effect of allicin on human esophageal cancer cell line EC 109 and its possible mechanism by comparison with chemotherapeutic drugs .METHODS:The EC109 cells were treated with different concentrations of allicin , 5-fluorouracil and cisplatin .The cell viability was detected by CCK 8 assay and the activ-ity of lactic dehydrogenase (LDH) was analyzed at 6 h, 12 h, 24 h, 48 h and 72 h.The apoptosis of the EC109 cells in-duced by Z-VAD-FMK, allicin, allicin+Z-VAD-FMK, 5-fluorouracil and cisplatin was analyzed by flow cytometry with Annexin V-FITC and PI double staining .The enzyme activity changes of caspase-3, caspase-8 and caspase-9 were detected by spectrophotometry .RESULTS:Allicin had inhibitory effect on the growth of the EC 109 cells and killed them in con-centration-dependent and time-dependent manners .LDH activity was decreased compared with 5-fluorouracil and cisplatin . The increased activity of caspase-3 and caspase-8 in allicin-treated cells was statistically significant , but caspase-9 activity changed without statistical significance .CONCLUSION:Allicin inhibits the growth of EC109 cells in concentration-and time-dependent manners through extrinsic apoptosis pathways activated by caspase -8, and the side effects are weaker com-pared with 5-fluorouracil and cisplatin .

Antitumor effect of allicin on esophageal cancer EC109 cells compared with chemotherapeutics in vitro / 中国病理生理杂志

AIM:To investigate the inhibitory effect of allicin on human esophageal cancer cell line EC 109 and its possible mechanism by comparison with chemotherapeutic drugs .METHODS:The EC109 cells were treated with different concentrations of allicin , 5-fluorouracil and cisplatin .The cell viability was detected by CCK 8 assay and the activ-ity of lactic dehydrogenase (LDH) was analyzed at 6 h, 12 h, 24 h, 48 h and 72 h.The apoptosis of the EC109 cells in-duced by Z-VAD-FMK, allicin, allicin+Z-VAD-FMK, 5-fluorouracil and cisplatin was analyzed by flow cytometry with Annexin V-FITC and PI double staining .The enzyme activity changes of caspase-3, caspase-8 and caspase-9 were detected by spectrophotometry .RESULTS:Allicin had inhibitory effect on the growth of the EC 109 cells and killed them in con-centration-dependent and time-dependent manners .LDH activity was decreased compared with 5-fluorouracil and cisplatin . The increased activity of caspase-3 and caspase-8 in allicin-treated cells was statistically significant , but caspase-9 activity changed without statistical significance .CONCLUSION:Allicin inhibits the growth of EC109 cells in concentration-and time-dependent manners through extrinsic apoptosis pathways activated by caspase -8, and the side effects are weaker com-pared with 5-fluorouracil and cisplatin .

Value of combined utilization of urinary CysC and NAG in the diagnosis of renal tubules damage / 国际检验医学杂志

Objective To discuss the diagnostic value of combined utilization of urinary cystatin C (CysC) and β‐N‐acetyl‐glu‐cosaminidase (NAG) in renal tubules injury .Methods Urine samples were collected from 130 cases of patients with renal tubular damage (case group) and 100 cases of health individuals (normal control group) ,respectively .The concentration of CysC and the activity of NAG in urine were detected .Results The sensitivity ,specificity ,and positive predictive value of combined utilization of CysC and NAG in diagnosis of renal tubules damage were 85 .4% ,89 .6% and 82 .1% ,respectively .The concentration of CysC and the activity of NAG in case group after treatment were both significantly different from those before treatment (P<0 .05) .Conclu‐sion Combined utilization of urinary CysC and NAG has a significant value for the diagnosis and the therapeutic monitoring in re‐nal tubules injury .

Alterations of protein phosphatase-2A in peripheral lymphocytes in mild cognition impairment and Alzheimer's disease / 中华神经科杂志

Objective To explore the alterations of protein phosphatase-2A (PP-2A) in lymphocytes in mild cognition impairment (MCI) and Alzheimer's disease (AD).Methods The activity PP-2A of was measured by ~(32)p liquid seintillography for incorporated radioactivity in control group(n=11) , the MCI group(n=11),and the AD group(n=11).The expression of PP-2A was determined by Western blot.Results In the control group,the activity of PP-2A (1.01?0.09) and the expression of PP-2A (0.96?0.07) were high while in the MCI group,the activity of PP-2A (0.71?0.12) and the expression of PP-2A (0.80?0.05) were decreased (both P

Effects of bilateral subthalamic nucleus stimulation on resting-state cerebral glucose metabolism in advanced Parkinson's disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The major neuropathological symptoms of Parkinson's disease (PD) consist of a loss of pigmented dopaminergic neurons in the substantia nigra and the presence of Lewy bodies. This study was to investigate the effects of bilateral subthalamic nucleus (STN) stimulation on resting-state cerebral glucose metabolism in advanced PD, and investigate the mechanism of deep brain stimulation (DBS).</p><p><b>METHODS</b>Seven consecutive advanced PD patients (4 men and 3 women, mean age 64 +/- 4 years, mean H-Y disability rating 4.4 +/- 0.65) receiving bilateral STN DBS underwent 18F-fluorodeoxyglucose (18F-FDG)/positron-emission tomography (PET) examinations at rest both preoperatively and one month postoperatively, with STN stimulation still on. The unified PD rating scale was used to evaluate the clinical state under each condition. Statistical parametric mapping (SPM) was used to investigate the regional cerebral metabolic rates of glucose (rCMRGlu) during STN stimulation, and to compare these values to rCMRGlu preoperation.</p><p><b>RESULTS</b>STN stimulation clearly improved clinical symptoms in all patients. A significant increase in rCMRGlu was found in the bilateral lentiform nucleus, brainstem (midbrain and pons), bilateral premotor area (BA6), parietal-occipital cortex, and anterior cingulated cortex, and a marked decrease in rCMRGlu was noted in the left limbic lobe and bilateral inferior frontal cortex (P < 0.05).</p><p><b>CONCLUSION</b>Bilateral STN stimulation may activate the projection axon from the STN, improving clinical symptoms in advanced PD patients by improving both ascending and descending pathways from the basal ganglia and increasing the metabolism of higher-order motor control in the frontal cortex.</p>

Mechanisms of the subthalamic nuclei high frequency stimulation in Parkinson' s disease / 中华神经科杂志

Objective To identify the effects of the subthalamic nuclei(STN)high frequency stimulation(HFS)on striatal and nigral dopaminergic metabolism in rats.Methods The effects of subthalamie nuclei high frequency stimulation(STN-HFS)on striatal dopaminergie metabolism was investigated in free moving rats.Reverse transcriptase polymerase chain reaction(RT-PCR)and Western blot of striatal and nigral tyrosine hydroxyiase(TH)were performed.Results Our data suggest that STN- HFS elevated TH protein(0.99?0.14 vs 0.33?0.08,P