Biomedical subjects

Hae Jeong Park

Publications and source records attributed to Hae Jeong Park.

11 recordsLinked to original sources

PubMed2006

Epigallocatechin gallate reduces hypoxia-induced apoptosis in human hepatoma cells.

Cell detachment from extracellular matrix is closely related to induction of apoptosis. Epigallocatechin gallate (EGCG) has been shown to have antioxidant effect and to protect hypoxia-induced damage. We investigated whether EGCG reduced hypoxia-induced apoptosis and cell detachment in HepG2 cells. EGCG prevented cell death by hypoxia (0.5% O2) in a dose-dependent manner (hypoxic cell viability, 54.67%). RT-PCR and caspase3 activity assay showed that the hypoxia-induced cell death was caused by apoptosis increasing mRNA level of BAX, CASP3, and caspase3 activity. EGCG reduced increase of these mRNA and caspase3 activity. Western blot analysis and immunocytochemistry showed that EGCG increased cell adhesion proteins including E-cadherin (CDH1), tumor-associated calcium signal transducer 1 (TACSTD1), and protein tyrosine kinase 2 (PTK2) decreased by hypoxia. Hypoxia-induced apoptosis in HepG2 cells, and EGCG contributed to the HepG2 cell survival by attenuating the apoptosis.

Antigens, Neoplasm↗

PubMed2006

BNP as a marker of the heart failure in the treatment of imatinib mesylate.

Since its introduction 6 years ago, imatinib mesylate, a selective tyrosine kinase inhibitor, has been a phenomenon in treating chronic myelogenous leukemia (CML) with remarkably superior cytogenetic and molecular response rates at all stages of CML followed by longer progression free survival. Despite its extraordinarily high efficacy, adverse effects of imatinib mesylate such as edema, liver toxicity and fluid retention syndromes have been reported. Here we, for the first time, report development of heart failure in patients on imatinib mesylate medication and the possibility of brain natriuretic peptide (BNP) as a potential diagnostic (or predicting) marker for heart failure. Since plasma BNP levels in the two patients were exceptionally high, we then explored the possibility of genetic association of BNP with the development of heart failure to find no positive association.

Adult↗

PubMed2006

Microarray analysis of transcription factor gene expression in melatonin-treated human peripheral blood mononuclear cells.

The existence of specific melatonin-binding sites in lymphoid cells led to the discovery of signal transduction pathway for melatonin in human lymphocytes and immunomodulatory role of melatonin in immune cells. In recent years, transcriptional regulation of melatonin on various transcription factors has been demonstrated. Therefore, this study was designed to assess by cDNA microarray analysis the regulatory effects of melatonin on transcription factors in human peripheral blood mononuclear cells (PBMCs). Forty-six genes were upregulated and 23 were downregulated more than twofold in melatonin-treated PBMCs. Of the more than twofold upregulated transcription factor genes, homeo box A4 (HOXA4), forkhead box O1A (FOXO1A), transcription elongation factor B (SIII), polypeptide 3 (TCEB3), and peroxisome proliferative activated receptor delta (PPARD) were identified. Of the more than twofold downregulated genes, PHD finger protein 15 (PHF15) and zinc finger protein 33a (ZNF33A) were identified. In summary, identification of these genes by cDNA microarray analysis in response to melatonin administration may provide a foundation for further studies on the function of melatonin in human PBMCs.

Base Sequence↗

PubMed2005

IL4 receptor polymorphism is associated with increased risk of sudden deafness in Korean population.

The interleukin 4 receptor (IL4R) polymorphism Q576R (rs 180275) has been well known to be associated with atopy and other inflammatory diseases. A single nucleotide polymorphism (SNP) A > G transition potentiates the binding specificity of the adjacent tyrosine residue. In this study we investigated the possible relationship between sudden deafness (SD) and IL4R polymorphism Q576R in 97 Korean SD patients and 613 controls using pyrosequencing method. The odds ratio (OR) for SD associated with the G vs. A allele was 2.58 [P < 0.0001, 95% confidence interval (CI) = 1.84-3.60]. We then sub-grouped SD into Tinnitus positive (+) and Tinnitus negative (-). G allele in Tinnitus (+) is significantly associated with the development of Tinnitus (+) [X(2) = 32.02, P < 0.0001, OR (95% CI) = 2.74 (1.91-3.93)] but not with Tinnitus (-). Taken together these results suggest that G allele could be a risk factor for SD.

Female↗

PubMed2005

Citri Reticulatae Viride Pericarpium extract induced apoptosis in SNU-C4, human colon cancer cells.

Citri Reticulatae Viride Pericarpium (CR) has been used traditionally in Korea to promote the Liver Qi activity and the function of digestive system. We investigated whether the immature peels of Citrus reticulata Blanco (Rutaceae) induced cell-death on SNU-C4, human colon cancer cells. Cytotoxicity of CR was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cell death was identified as apoptosis using 4,6-diamidineo-2-phenylindole (DAPI) staining and terminal deoxy-nucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay. The expression of pro-apoptotic gene, Bax, was increased and the expression of anti-apoptotic gene, Bcl-2, was decreased by CR-treatment. The expression and activity of major apoptotic gene, caspase-3 was significantly increased by CR-treatment. Considering the above results, CR could induce the apoptosis on SNU-C4, human colon cancer cells via Bax-related caspase-3 activation. And it might provide the experimental data for the future clinical use of CR on colon cancer.

Antineoplastic Agents↗

PubMed2005

Positive relationship between melatonin receptor type 1B polymorphism and rheumatoid factor in rheumatoid arthritis patients in the Korean population.

Melatonin is reported to be an anti-inflammatory agent. No genetic study concerning the association between melatonin and inflammatory disease has yet been reported. Here we performed a polymorphism study on the melatonin receptor type 1B (MTNR1B) in Korean rheumatoid arthritis (RA) patients and controls. The polymorphism of MTNR1B located in 3'-untranslated region (rs 1562444) was selected for its higher rate of heterozygosity among other single nucleotide polymorphisms (SNPs) in both MTNR1A and MTNR1B genes and investigated in RA patients (n = 173) and healthy controls (n = 195) by polymerase chain reaction-restriction fragment length polymorphism assay using NlaIII restriction enzyme. No statistically significant difference in either genotype distribution or allele frequency was observed between RA patients and controls. The genotype distributions and allele frequencies of rheumatoid factor negative [RF(-)] patients were similar to those of controls. However, statistical analysis of genotype revealed a significant association (chi2 = 6.42, P = 0.04) is present between RF(+) and MTNR1B SNP (rs 1562444). Although no statistically significant difference in allele frequency between RF(+) and controls was observed (chi2 = 2.75, P = 0.10), the results might suggest that MTNR1B SNP (rs 1562444) is associated with the presence of RF in RA. This is the first study, to our knowledge, to report a positive genetic relationship between melatonin and RA.

Arthritis, Rheumatoid↗

PubMed2005

Citrus Reticulata blanco induces apoptosis in human gastric cancer cells SNU-668.

Citrus fruits have been known to reduce the proliferation of many cancer cells. The antiproliferative effects of Citrus reticulata Blanco (CR) extract, the immature tangerine peel, on human gastric cancer cell line SNU-668 were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, 4,6-diamidineo-2-phenylindole staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay, reverse transcription-polymerase chain reaction expressions of BCL-2, BAX and CASP-3 genes, caspase-3 activity, and immunocytochemistry of caspase-3. From the results of the morphological and biochemical assays, CR (50 microg/ml) increased the apoptosis of human gastric cancer cells with typical apoptotic characteristics, including morphological changes of chromatin condensation and apoptotic body formation. CR (50 microg/ml) reduced the expression of BCL-2, whereas the expression of BAX and CASP-3 was increased compared with the control group. Furthermore, caspase-3 activity and caspase-3 protein expression in the CR-treated group was significantly increased compared with that in control group. These results suggest that CR may induce the apoptosis through the caspase-3 pathway in human gastric cancer cells.

Antineoplastic Agents↗

PubMed2005

Development of Korean standard brain templates.

We developed age, gender and ethnic specific brain templates based on MR and Positron-Emission Tomography (PET) images of Korean normal volunteers. Seventy-eight normal right-handed volunteers (M/F=49/29) underwent 3D T1-weighted SPGR MR and F-18-FDG PET scans. For the generation of standard templates, an optimal target brain that has the average global hemispheric shape was selected for each gender. MR images were then spatially normalized by linear transformation to the target brains, and normalization parameters were reapplied to PET images. Subjects were subdivided into 2 groups for each gender: the young/midlife (<55 yr) and the elderly groups. Young and elderly MRI/PET templates were composed by averaging the spatially normalized images. Korean templates showed different shapes and sizes (mean length, width, and height of the brains were 16.5, 14.3 and 12.1 cm for man, and 15.6, 13.5 and 11.4 cm for woman) from the template based on Caucasian (18.3, 14.2, and 13.3 cm). MRI and PET templates developed in this study will provide the framework for more accurate stereotactic standardization and anatomical localization.

Adolescent↗

PubMed2004

Epidermal growth factor gene polymorphism is different between schizophrenia and lung cancer patients in Korean population.

Low incidence of cancer in schizophrenia is one of the interesting puzzles in psychiatric field over decades. Analysis of genetic difference between schizophrenia and lung cancer might provide us with possible clues to understand molecular mechanisms of pathophysiology of schizophrenia. Epidermal growth factor (EGF), one of the potent growth promoting factors, has been studied for its roles in cancer development. EGF is also known to be involved in cognitive function. In order to analyze the genetic difference between schizophrenia and lung cancer, polymorphism of EGF gene was studied from 174 schizophrenia patients, 122 lung cancer patients and 132 controls in Korean population. Genotype frequency analysis of EGF gene (AluI restriction site, 5'-UTR, rs4444903) in the EGF gene was studied. The genotype and allele frequencies of the AluI polymorphism showed significant differences between schizophrenia and lung cancer patients [p<0.0001; p<0.0001, odds ratio (95% CI), 0.3690 (0.2600-0.5236)]. When compared with controls, schizophrenia patients showed no significant differences from controls in genotype and allele frequencies [p=0.5151; p=0.3516, odds ratio (95% CI), 0.8589 (0.6235-1.1830)]. However, lung cancer patients showed significant differences from controls in genotype and allele frequencies [p<0.0001; p<0.0001, odds ratio (95% CI), 2.3275 (1.6082-3.3687)]. These results indicate that schizophrenia is not associated with AluI polymorphism of EGF gene and EGF gene polymorphism is different between schizophrenia and lung cancer patients.

5' Untranslated Regions↗

PubMed2004

Coptidis rhizoma induces apoptosis in human colorectal cancer cells SNU-C4.

Coptidis rhizoma has been used as traditional herb medicine in gastrointestinal disorders in the Eastern Asia. We investigated whether the anticancer effects of the C. rhizoma induced apoptosis on human colorectal cancer cells SNU-C4. The cytotoxic effect of C. rhizoma was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. To determine apoptotic cell death, 4,6-diamidino-2-phenylindole (DAPI) staining, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, reverse transcription-polymerase chain reaction (RT-PCR) and caspase-3 enzyme assay were performed. In this study, C. rhizoma treatment (100 microg/ml) revealed typical morphological apoptotic features. Additionally, C. rhizoma treatment (100 microg/ml) increased levels of BAX and CASPASE-3, and decreased levels of BCL-2. Caspase-3 enzyme activity by treatment of C. rhizoma (100 microg/ml) also significantly increased compared to the control (p < 0.05). These data indicate that C. rhizoma caused cell death by apoptosis through caspase pathways on human colorectal cancer cells SNU-C4.

Anticarcinogenic Agents↗

PubMed2003

Functional disconnection between the prefrontal and parietal cortices during working memory processing in schizophrenia: a[15(O)]H2O PET study.

OBJECTIVE: The prefrontal-parietal circuits have been reported to play an important role in working memory. The purpose of this study was to use direct neuroimaging to address whether interregional correlation in the prefrontal-parietal circuits is impaired in schizophrenia. METHOD: [(15)O]H(2)O positron emission tomography was used to compare regional blood flow changes in 12 schizophrenic and 12 healthy comparison subjects during the n-back sequential-picture working memory task. Interregional correlation was assessed by correlating the regional activation of the lateral prefrontal area with that of other activated areas in each subject group. RESULTS: Dorsolateral prefrontal activation was observed around the right superior frontal sulcus in the healthy subjects, and ventrolateral prefrontal activation below the right inferior frontal sulcus was observed in the schizophrenic patients. Activation in the right lateral prefrontal cortex was significantly correlated with activation in the bilateral inferior parietal region in the healthy subjects but was not correlated with any regional activation in the patients. CONCLUSIONS: The findings suggest prefrontal-parietal functional disconnection, particularly prefrontal dissociation and abnormal prefrontal-parietal interaction, during working memory processing in schizophrenia.

Adult↗