Impact of Several Types of Stresses on Short-term Memory and Apoptosis in the Hippocampus of Rats / 대한배뇨장애요실금학회지

PURPOSE: Stress has a deteriorating effect on hippocampal function. It also contributes to symptom exacerbation in many disease states, including overactive bladder and interstitial cystitis/bladder pain syndrome. We investigated the effects of various types of stresses (restraint, noise, and cold) on short-term memory and apoptosis in relation with corticotropin-releasing factor (CRF) expression. METHODS: Rats in the restraint stress group were restrained in a transparent Plexiglas cylinder for 60 minutes twice daily. Rats in the noise stress group were exposed to the 120 dB supersonic machine sound for 60 minutes twice daily. Rats in the cold stress group were placed in a cold chamber at 4degrees C for 60 minutes twice daily. Each stress was applied for 10 days. A step-down avoidance test for short-term memory, immunohistochemistry for caspase-3 expression, and western blot analysis for Bax and Bcl-2 expressions were conducted. RESULTS: Latency time was decreased and CRF expression in the hippocampal dentate gyrus and hypothalamic paraventricular nucleus were increased in all of the stress groups. The number of caspase-3-positive cells in the hippocampal dentate gyrus was increased and the expressions of Bax and Bcl2 in the hippocampus were decreased in all of the stress groups. CONCLUSIONS: All of the stress groups experienced short-term memory impairment induced by apoptosis in the hippocampus. The present results suggest the possibility that these stresses affecting the impairment of short-term memory may also induce functional lower urinary tract disorders.

A Promoter SNP (rs1800682, -670C/T) of FAS Is Associated with Stroke in a Korean Population

The Fas (TNF receptor superfamily, member 6) (FAS)/FAS ligand (FASLG) interaction plays a central role in the regulation of programmed cell death. FAS and FASLG polymorphisms in promoter regions affect transcriptional activities. To investigate whether FAS and FASLG polymorphisms are associated with the development and clinical phenotypes of stroke, 2 promoter single nucleotide polymorphisms (SNPs) in FAS (rs1800682, -670C/T) and FASLG (rs763110, -844C/T) were selected and genotyped by direct sequencing in 220 stroke patients [107 ischemic stroke (IS), 77 intracerebral hemorrhage (ICH), and 36 subarachnoid hemorrhage (SAH)] and 369 control subjects. For the analysis of clinical symptoms, all stroke patients were divided into 3 clinical phenotypes according to the respective results of the National Institutes of Health Stroke Survey (NIHSS) and the Modified Barthel Index (MBI) and the presence or absence of complex regional pain syndrome (CRPS). The SNPStats, SNPAnalyzer, and Helixtree programs were used to analyze the genetic data. Multiple logistic regression models (codominant, dominant, and recessive) were used to estimate odds ratios (ORs), 95% confidence intervals (CIs), and p-values. The promoter SNP rs1800682 was associated with stroke in the codominant (OR=0.48, 95% CI=0.25-0.94, p=0.04) and dominant models (OR=0.51, 95% CI=0.30-0.87, p=0.011). However, a FASLG SNP (rs763110) was not in Hardy-Weinberg equilibrium (p<0.05). In the analysis of stroke types, rs1800682 was associated with IS in the codominant (OR=0.30, 95% CI=0.12-0.74, p=0.025), dominant (OR=0.44, 95% CI=0.23-0.88, p=0.018), and recessive models (OR=0.45, 95% CI=0.21-0.99, p=0.042). The genotype frequencies of rs1800682 were different between ICH and controls in the dominant model (OR=0.49, 95% CI=0.26-0.94, p=0.031) but not between SAH and controls. In the analysis of clinical symptoms, however, rs1800682 was not related to the 3 clinical phenotypes (NIHSS, MBI, and CRPS). These results suggest that a promoter SNP (rs1800682, -670C/T) in FAS may be associated with the development of stroke in the Korean population.

Effect of Melatonin during Recovery of Tissue Injury after Intestine Ischemia-Reperfusion

PURPOSE: It is now well recognized that reperfusion of ischemic tissues initiates a complex series of reactions that can paradoxically injure tissues. Apoptosis occurs in select cell populations during morphologic development and during cellular injury, including oxygen radical exposure, ischemia-reperfusion, and sepsis. Thus, in this study, we examined relation of the melatonin effect to the injection time and the dose, and role of melatonin in apoptosis. METHODS: Intestinal ischemia-reperfusion injury was induced in rats by clamping the superior mesenteric artery for 30 minutes. After reperfusion injury for 30 minutes, the experimental group was administered melatonin (10 mg/kg) intraperitoneally and the control group received saline and ethanol. At 30 minutes, 60 minutes, and 90 minutes, 1) pulmonary histological assessments (interstitial PMNs/10HPFs and lung (alveolar) injury score), 2) alveolar microvascular permeability assessments (wet-weignt to dry-weight ratio and lipid peroxidation activity, malondialdehyde, MDA), and 3) western blotting assessments (p53, p21, Bax, and bcl-2) were made. For comparison, long- time (60-minute) reperfusion and double- dosage melatonin (20 mg/kg) were also studied. RESULTS: The lung injury score was 1.00+/-0 in the melatonin group at 90 minutes and 3.28+/-0.30 in the saline group (p0.05). A marked difference was found between the ischemia-reperfusion control group and the experimental group at 90 minutes regarding lipid peroxidation activity (Malondialdehyde, 16.45+/-0.19 micrometer vs 10.93+/-0.11 micrometer, p<0.01). In the melatonin group, p21 expressions were found to be much more than in the control group. But, p53, bcl-2, and Bax expressions were found to be in the control group. CONCLUSION: Melatonin injection within 60 min after reperfusion may promote recovery of reperfusion injury, but double-dose melatonin injection was inefficacious. Also, melatonin inhibit apoptosis by p21 expression.

Caffeine Induces Apoptosis in Human Neuroblastoma Cell Line SK-N-MC

Caffeine is one of the most widely consumed neuroactive drugs, coming mostly from everyday beverages such as coffee and tea. To investigate whether caffeine induces apoptosis in the central nervous system, 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay, 4,6-diamidino-2-phenylindole (DAPI) staining, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, flow cytometric analysis, DNA fragmentation assay, and caspase-3 enzyme assay were performed on SK-N-MC human neuroblastoma cells. Cells treated with caffeine at concentrations as high as 10 mM exhibited several characteristics of apoptosis. In addition, caffeine was shown to increase the caspase-3 activity. These results suggest that high-dose of caffeine induces apoptosis in human neuroblastoma cells, probably by increasing the caspase-3 enzyme activity.

p53 Mutations in Advanced Supraglottic Cancer / 대한방사선종양학회지

PURPOSE: To determine the prognostic significance of p53 mutations in advanced supraglottic cancer patients. MATERIALS AND METHODS: Twenty-six patients with pertinent tissue materials among 60 patients diagnosed as advanced supraglottic cancer in Kyung Hee university hospital and received total or partial laryngectomy followed by radiation therapy were enrolled. Immunohistochemical staining using DO7 monoclonal antibody was performed. Tumor specimens were analyzed for p53 mutations in exons 5 through 8 by using PCR-SSCP analysis followed by DNA sequencing of all variants. RESULTS: p53 mutations were present in 8 cases among 26 patiets. Mutations within exon 5 were 3 cases, exon 6 were 4 cases, and exon 7 was 1 case. Mean survival time was 70.2 months in patients without mutations, 61.3 months with mutations but there was no statistically significant differences (p=0.596). Mutations were 25% in stage III and 36% in stage IV but there was no statistically significant differences (p=0.563). Mutations were 25% in lymph node negative group and 42% in lymph node positive group but there was no statistically significant differences (p=0.437). CONCLUSION: The presence of a p53 mutation detected by PCR-SSCP is not associated with survival, stage and lymph node status.

The Effect of Melatonin on Mouse Jejunal Crypt Cell Survival and Apoptosis / 대한방사선종양학회지

PURPOSE: To evaluate protective mechanism of melatonin against radiation damage and its relationship with apoptosis in mouse jejunum. MATERIALS AND METHODS:' 168 mice were divided into 28 groups according to radiation dose and melatonin treatment. To analysis crypt survival, microcolony survival assay was done according to Withers an (l Elkind's method. To analysis apoptosis, TUNEL assay was done according to Labet-Moleur's method. RESULTS: Radiation protection effect of melatonin was demonstrated by crypt survival assay and its effect was stronger in high radiation dose area. Apoptosis index with 8 Gy irradiation was 18.4% in control group and 16.5% in melatonin treated group. After 18 Gy, apoptosis index was 17.2% in control group and 15.4% in melatonin treated group. Apoptosis index did not show statistically significant difference between melatonin treated group and control group. CONCLUSION: Melatonin shows clear protective effect in mouse jejunum against radiation damage but it.', protective effect seems not to be related with apoptosis protection effect.