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1.
Diabet Med ; 36(10): 1312-1318, 2019 10.
Article in English | MEDLINE | ID: mdl-31254366

ABSTRACT

AIM: Few data are available on the gender-related differences in the prognostic impact of diabetes in people with heart failure. This study was performed to investigate whether there is a gender difference in the association between diabetes and long-term clinical outcomes in people hospitalized for heart failure. METHODS: A total of 3162 people hospitalized with heart failure (aged 67.4 ± 14.1 years, 50.4% females) from the data set of the nationwide registry were analysed. The primary endpoint was a composite of all-cause mortality and heart failure readmission. RESULTS: People with diabetes (30.5% for males vs. 31.1% for females, P = 0.740) were older and had more unfavourable risk factors and laboratory findings than those without diabetes in both genders. During a median follow-up period of 549 days, there were 1418 cases of composite events (44.8%). In univariable analysis, the coexistence of diabetes was significantly associated with a higher incidence of composite events in both genders (P < 0.05 each for males and females). In multivariable analysis, the prognostic impact of diabetes on the development of composite events remained significant in females even after controlling for potential confounders (hazard ratio 1.43, 95% confidence intervals 1.12-1.84; P = 0.004). However, an independent association between diabetes and composite events was not seen in males in the same multivariable analysis (P > 0.05). CONCLUSIONS: In people with heart failure, the impact of diabetes on long-term mortality and heart failure readmission seems to be stronger in females than in males. More careful and intensive management is needed especially in females with heart failure and diabetes.


Subject(s)
Diabetes Mellitus/epidemiology , Heart Failure/epidemiology , Sex Factors , Aged , Aged, 80 and over , Comorbidity , Diabetes Mellitus/mortality , Female , Heart Failure/mortality , Hospitalization , Humans , Male , Middle Aged , Patient Readmission , Prognosis , Registries , Republic of Korea/epidemiology , Risk Factors
2.
Diabet Med ; 32(4): 477-86, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25472691

ABSTRACT

AIMS: To evaluate the effects of gestational diabetes and pre-existing diabetes on maternal morbidity and medical costs, using data from the Korea National Health Insurance Claims Database of the Health Insurance Review and Assessment Service. METHODS: Delivery cases in 2010, 2011 and 2012 (459 842, 442 225 and 380 431 deliveries) were extracted from the Health Insurance Review and Assessment Service database. The complications and medical costs were compared among the following three pregnancy groups: normal, gestational diabetes and pre-existing diabetes. RESULTS: Although, the rates of pre-existing diabetes did not fluctuate (2.5, 2.4 and 2.7%) throughout the study, the rate of gestational diabetes steadily increased (4.6, 6.2 and 8.0%). Furthermore, the rates of pre-existing diabetes and gestational diabetes increased in conjunction with maternal age, pre-existing hypertension and cases of multiple pregnancy. The risk of pregnancy-induced hypertension, urinary tract infections, premature delivery, liver disease and chronic renal disease were greater in the gestational diabetes and pre-existing diabetes groups than in the normal group. The risk of venous thromboembolism, antepartum haemorrhage, shoulder dystocia and placenta disorder were greater in the pre-existing diabetes group, but not the gestational diabetes group, compared with the normal group. The medical costs associated with delivery, the costs during pregnancy and the number of in-hospital days for the subjects in the pre-existing diabetes group were the highest among the three groups. CONCLUSIONS: The study showed that the rates of pre-existing diabetes and gestational diabetes increased with maternal age at pregnancy and were associated with increases in medical costs and pregnancy-related complications.


Subject(s)
Delivery, Obstetric/economics , Diabetes Complications/economics , Diabetes, Gestational/economics , Pregnancy in Diabetics/economics , Adolescent , Adult , Delivery, Obstetric/statistics & numerical data , Diabetes Complications/complications , Female , Health Care Costs , Humans , Middle Aged , Pregnancy , Pregnancy, Multiple/statistics & numerical data , Prenatal Care/economics , Republic of Korea , Young Adult
3.
Tissue Antigens ; 84(3): 277-84, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24851935

ABSTRACT

Because Korean society is fast becoming multi-ethnic, the determination of ambiguous human leukocyte antigen (HLA) types using HLA allele frequencies is becoming less applicable. In this study, we focused on the development of new technical methods to directly resolve the ambiguities arising from HLA genotyping. One hundred and fifty unrelated healthy Korean adults were included in this study. All alleles from each HLA locus were first divided into 2-4 groups, with each group amplified in a single PCR tube (multi-group-specific amplification, MGSA). To resolve phase ambiguities, some allele groups were also amplified separately in small group-specific amplification (SGSA) tubes. In order to then resolve incomplete sequence ambiguities, primers for MGSA and SGSA were initially designed to cover additional exons. If needed, a heterozygous ambiguity resolving primer (HARP) or sequence specific primer (SSP) was also used. When MGSA and SGSA methods were applied, the rate of phase ambiguity was greatly reduced to an average of 6% (1.3% in HLA-A, 15.7% in -B, and 2.0% in -C). Additional HARP and SSP methods could resolve all the phase ambiguities. Using our proposed method, we also detected three alleles that have not been previously reported in Korea, C*04:82, C*07:18, and C*08:22, and report 6-digit level HLA allele and haplotype frequencies among Koreans. In conclusion, the use of MGSA/SGSA for the initial amplification step is a cost-effective method facilitating timely and accurate reporting, given the continuing increase in the ethnic diversity of the Korean population. The MGSA described here can be applicable to various populations and thus could be shared by the majority of HLA typing laboratories. However, efforts to solve HLA ambiguity should continue, because SGSA, HARPs and SSPs would be specific to a particular population.


Subject(s)
Asian People/genetics , DNA Fingerprinting/methods , HLA Antigens/genetics , Histocompatibility Testing/methods , Adult , Cohort Studies , DNA Primers/genetics , Gene Frequency , Genotype , Haplotypes , Humans , Polymerase Chain Reaction , Polymorphism, Genetic , Republic of Korea
5.
Tissue Antigens ; 78(1): 38-44, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21554252

ABSTRACT

Major histocompatibility complex (MHC) class I chain-related gene B (MICB) is located within the human MHC class I region. The location of MICB in the MHC region may imply the presence of linkage disequilibrium with polymorphic MICA and human leukocyte antigen (HLA) loci. MICB is also polymorphic; however, MICB polymorphisms have not been investigated in Koreans. Using sequence-based typing (SBT), we estimated the allelic frequencies of MICB and haplotypes with MICA, HLA-B, and HLA-DRB1 at high resolution in a population of 139 unrelated Korean individuals. Eight MICB alleles were identified. The most frequent allele was MICB*005:02/*010 (57.2%), followed by *002 (11.5%), *004 (8.3%), *005:03 (8.3%), and *008 (6.8%). The most common two-locus haplotypes were MICB*005:02/*010-MICA*010 (19.4%), MICB*005:02/*010-DRB1*15:01 (6.5%), and MICB*005:02/*010-B*15:01 (10.4%); the most common three-locus haplotypes were B*15:01-MICA*010-MICB*005:02/*010 (5.8%) and MICA*010-MICB*005:02/*010-DRB1*04:06 (10.4%); and the most common four-locus haplotype was B*15:01-MICA*010-MICB*005:02/*010-DRB1*04:06 (5.8%). This is the first study to provide information about MICB allele frequencies and haplotypes with HLA in Koreans. These study results should help understand mechanisms of disease association between the MICB locus and neighboring loci in Koreans.


Subject(s)
HLA Antigens/genetics , Histocompatibility Antigens Class I/genetics , Polymorphism, Genetic , Alleles , Asian People/genetics , Ethnicity/genetics , Gene Frequency , Haplotypes , Humans , Korea , Linkage Disequilibrium
6.
Tissue Antigens ; 78(2): 154-5, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21457150

ABSTRACT

The new allele B*40:155N showed five nucleotide insertion between nucleotide 594 and 595 (codon 174 and 175) compared to B*40:01:01.


Subject(s)
HLA-B Antigens/genetics , Alleles , Amino Acid Sequence , Base Sequence , Exons , Genetic Variation , Genotype , Humans , Molecular Sequence Data , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
7.
Tissue Antigens ; 77(4): 344-6, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21388362

ABSTRACT

The new allele DQB1*05:06 showed one nucleotide difference with DQB1*05:03:01 at codon 40 (TTC/TTG).


Subject(s)
Alleles , Codon/genetics , HLA-DQ Antigens/genetics , Asian People , HLA-DQ beta-Chains , Humans , Korea
8.
Oncogene ; 30(30): 3345-59, 2011 Jul 28.
Article in English | MEDLINE | ID: mdl-21423208

ABSTRACT

Several studies have shown physiological functions of interleukin (IL)-32, a novel cytokine. However, the role of IL-32 in cancer development has not been reported. In this study, we showed that IL-32γ inhibited tumor growth in IL-32γ-overexpressing transgenic mice inoculated with melanoma as well as colon tumor growth in xenograft nude mice inoculated with IL-32γ-transfected colon cancer cells (SW620). The inhibitory effect of IL-32γ on tumor growth was associated with the inhibition of constitutive activated nuclear transcription factor-κB (NF-κB) and of signal transducer and activator of transcription 3 (STAT3). The expression of antiapoptotic, cell proliferation and tumor-promoting genes (bcl-2, X-chromosome inhibitor of apoptosis protein (IAP), cellular IAP and cellular FADD-like IL-1ß-converting enzyme-inhibitory protein, cyclin D), cyclin-dependent kinase 4, cycolooxygenase-2 and inducible nitric oxide synthase was decreased, whereas the expression of apoptotic target genes (caspase-3 and -9, bax) increased. In tumor, spleen and blood, the number of cytotoxic CD8(+) T cells and CD57(+) natural killer cells and the levels of IL-10 increased, but that of tumor necrosis factor-α (TNF-α), IL-1ß and IL-6 decreased. We also found that forced overexpression of IL-32γ inhibited colon cancer cell (SW620 and HCT116) growth accompanied with the inhibition of activated NF-κB and STAT3 in vitro. In addition, when IL-32γ was knocked down by small interfering RNA (siRNA) or neutralized with an anti-IL-32γ antibody, IL-32γ-induced colon cancer cell growth inhibition, the IL-32γ-induced decrease of TNF-α, IL-1 and IL-6 production, and the increase of IL-10 production were abolished. However, siRNA of NF-κB and STAT3 augmented IL-32γ-induced colon cancer cell growth inhibition. These findings indicate significant pathophysiological roles of IL-32γ in cancer development.


Subject(s)
Colonic Neoplasms/pathology , Interleukins/metabolism , Melanoma/pathology , NF-kappa B/metabolism , STAT3 Transcription Factor/metabolism , Signal Transduction , Animals , Apoptosis/genetics , CD8-Positive T-Lymphocytes/metabolism , Cell Proliferation , Cell Transformation, Neoplastic , Colonic Neoplasms/genetics , Colonic Neoplasms/immunology , Colonic Neoplasms/metabolism , Cytokines/metabolism , Gene Silencing , HCT116 Cells , Humans , Interleukins/genetics , Killer Cells, Natural/metabolism , Male , Melanoma/genetics , Melanoma/immunology , Melanoma/metabolism , Mice , Mice, Inbred BALB C , Mice, Transgenic , Signal Transduction/genetics
9.
Prostate Cancer Prostatic Dis ; 14(1): 63-8, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20938462

ABSTRACT

The aim of this study was to determine whether or not statins influence biochemical recurrence (BCR) in Korean patients undergoing surgical treatment for prostate cancer. We reviewed data from 687 men who underwent radical retropubic prostatectomy and who did not receive neoadjuvant treatment. Of these patients, 87 reported the use of preoperative statins at surgery. BCR-free survival was determined after exclusion of 78 patients with lymph node metastases and/or who received immediate adjuvant treatment. Patients on statin therapy were more likely to have a co-morbid disease (P < 0.05). Mean PSA (9.6 vs 13.6 ng ml(-1), P = 0.002) and PSA density (0.27 vs 0.38 ng ml(-1) ml(-1), P<0.001) were significantly lower in patients on statins. However, in the multivariable linear regression model, statin use was not associated with a decrease in PSA. Overall BCR for the entire cohort was not significantly different between the statin and nonstatin groups. On multivariate analysis, positive surgical margin and seminal vesicle invasion were independent risk factors for BCR-free survival, whereas other variables, including statin use, were not significant in predicting the risk of BCR. Patients with positive surgical margin and seminal vesicle invasion had a 2.1- (odds ratio, 2.15; 95% confidence interval, 1.29-3.57; P = 0.003) and 2.2-fold risk (odds ratio, 2.21; 95% confidence interval, 1.25-3.89; P = 0.006) of BCR. Preoperative statin use is not associated with reduced BCR following radical prostatectomy.


Subject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Prostate-Specific Antigen/blood , Prostatic Neoplasms/blood , Prostatic Neoplasms/drug therapy , Aged , Combined Modality Therapy/methods , Follow-Up Studies , Humans , Korea , Male , Middle Aged , Prostatectomy , Prostatic Neoplasms/surgery , Retrospective Studies , Risk Assessment , Treatment Outcome
10.
J Immunol ; 167(1): 497-504, 2001 Jul 01.
Article in English | MEDLINE | ID: mdl-11418688

ABSTRACT

Cervical carcinoma is the predominant cancer among malignancies in women throughout the world, and human papillomavirus (HPV) 16 is the most common agent linked to human cervical carcinoma. The present study was performed to investigate the mechanisms of immune escape in HPV-induced cervical cancer cells. The presence of HPV oncoproteins E6 and E7 in the extracellular fluids of HPV-containing cervical cancer cell lines SiHa and CaSki was demonstrated by ELISA. The effect of HPV 16 oncoproteins E6 and E7 on the production of IFN-gamma by IL-18 was assessed. E6 and E7 proteins reduced IL-18-induced IFN-gamma production in both primary PBMCs and the NK0 cell line. FACS analysis revealed that the viral oncoproteins reduced the binding of IL-18 to its cellular surface receptors on NK0 cells, whereas there was no effect of oncoproteins on IL-1 binding to its surface IL-1 receptors on D10S, a subclone of the murine Th cell D10.G4.1. In vitro pull-down assays also revealed that the viral oncoproteins and IL-18 bound to IL-18R alpha-chain competitively. These results suggest that the extracellular HPV 16 E6 and E7 proteins may inhibit IL-18-induced IFN-gamma production locally in HPV lesions through inhibition of IL-18 binding to its alpha-chain receptor. Down-modulation of IL-18-induced immune responses by HPV oncoproteins may contribute to viral pathogenesis or carcinogenesis.


Subject(s)
Adjuvants, Immunologic/physiology , Interferon-gamma/antagonists & inhibitors , Interleukin-18/physiology , Killer Cells, Natural/immunology , Leukocytes, Mononuclear/immunology , Oncogene Proteins, Viral/physiology , Papillomaviridae/immunology , Repressor Proteins , Adjuvants, Immunologic/metabolism , Binding, Competitive/immunology , Cell Line , Cell-Free System/chemistry , Cell-Free System/metabolism , Cells, Cultured , Humans , Interferon-gamma/biosynthesis , Interleukin-1/metabolism , Interleukin-18/antagonists & inhibitors , Interleukin-18/metabolism , Interleukin-18 Receptor alpha Subunit , Killer Cells, Natural/metabolism , Leukocytes, Mononuclear/metabolism , Oncogene Proteins, Viral/metabolism , Papillomavirus E7 Proteins , Protein Binding/immunology , Receptors, Interleukin/antagonists & inhibitors , Receptors, Interleukin/metabolism , Receptors, Interleukin-1/metabolism , Receptors, Interleukin-18 , Tumor Cells, Cultured
11.
J Biol Chem ; 276(22): 19089-93, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11279191

ABSTRACT

The MHC class II transactivator (CIITA) is a critical transcription factor that regulates genes involved in antigen presentation function. At least three functional forms of CIITA gene products are transcribed from three different promoters. The CIITA gene expressed in dendritic cells (DC-CIITA) has a unique first exon encoding an extended N-terminal region of CIITA. Here, we show that the N terminus of DC-CIITA has high homology to a caspase recruitment domain (CARD) found in components of apoptosis and nuclear factor-kappaB signaling pathways. However, DC-CIITA does not regulate cell death, nor does it induce nuclear factor-kappaB activity. Instead, DC-CIITA is transcriptionally a more potent activator of the MHC class II gene than the form expressed in B cells. A single amino acid substitution in the CARD of DC-CIITA, predicted to disrupt CARD-CARD interactions, diminished the transactivation potential of DC-CIITA. These results indicate that the CARD in the context of CIITA serves as a regulatory domain for transcriptional activity and may function to selectively enhance MHC class II gene expression in dendritic cells.


Subject(s)
Caspases/chemistry , Dendrites/metabolism , Nuclear Proteins , Trans-Activators/chemistry , Amino Acid Sequence , Apoptosis , Blotting, Western , Cell Line , Cell Nucleus/metabolism , DNA/metabolism , Dendritic Cells/metabolism , Dose-Response Relationship, Drug , Electrophoresis, Polyacrylamide Gel , Exons , Flow Cytometry , Humans , Luciferases/metabolism , Models, Genetic , Molecular Sequence Data , NF-kappa B/metabolism , Plasmids/metabolism , Promoter Regions, Genetic , Protein Isoforms , Protein Structure, Tertiary , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid , Signal Transduction , Trans-Activators/genetics , Trans-Activators/metabolism , Transcription, Genetic , Transcriptional Activation , Transfection
12.
Heart Vessels ; 16(1): 12-9, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11829213

ABSTRACT

Cardiomyocyte apoptosis is an important pathogenic mechanism in myocardial ischemia/reperfusion (I/R) injury. It has been shown that nitric oxide (NO) and the renin-angiotensin system (RAS) are closely related, and both systems regulate apoptotic cell death. However, the effects of NO modulation on myocardial apoptotic cell death and changes in the RAS in the I/R-injured myocardium have not been studied. Female Sprague-Dawley rats were randomized into three groups: NO synthesis inhibitor, N(G)-nitro-L-arginine-methyl ester (L-NAME, 10mg/kg); NO precursor, L-arginine (540mg/kg); and vehicle. The rats were then subjected to 45 min coronary occlusion followed by 4 h reperfusion. The TdT-mediated in situ nick and labeling (TUNEL) indices were 39.9%+/-0.8% at the border and 30.9%+/-1.2% at the center of the I/R area in the vehicle group. L-NAME administration significantly increased these TUNEL-positive cells to 45.3%+/-1.9% and 37.9%+/-1.3%, respectively (P < 0.05 each). L-arginine administration reduced the TUNEL index at the border zone with marginal significance (P = 0.08 vs vehicle group). I/R injury significantly reduced the angiotensin-converting enzyme (ACE) mRNA expression in the left (ventricular) free wall of vehicle group rats. However, ACE mRNA expression was 1.9 times greater in the L-NAME group than that in the vehicle group (P < 0.05). This study showed that the inhibition of NO synthesis increased apoptotic cardiomyocyte death and local ACE mRNA expression in the I/R-injured myocardium. Our observations indicate that NO, ACE, and apoptotic cardiomyocyte death are related to each other during I/R injury.


Subject(s)
Apoptosis , Nitric Oxide/biosynthesis , Peptidyl-Dipeptidase A/metabolism , Reperfusion Injury/metabolism , Animals , Female , In Situ Nick-End Labeling , Myocardium/cytology , Myocardium/metabolism , Myocardium/pathology , RNA, Messenger/metabolism , Random Allocation , Rats , Rats, Sprague-Dawley , Reperfusion Injury/genetics , Reperfusion Injury/pathology , Statistics, Nonparametric
14.
J Biol Chem ; 274(32): 22251-6, 1999 Aug 06.
Article in English | MEDLINE | ID: mdl-10428792

ABSTRACT

Calsequestrin is a high capacity Ca(2+)-binding protein in the junctional sarcoplasmic reticulum that forms a quaternary complex with junctin, triadin, and the ryanodine receptor. Transgenic mice with cardiac-targeted calsequestrin overexpression show marked suppression of Ca(2+)-induced Ca(2+) release, myocyte hypertrophy, and premature death by 16 weeks of age (Jones, L. R., Suzuki, Y. J., Wang, W., Kobayashi, Y. M., Ramesh, V., Franzini-Armstrong, C., Cleemann, L., and Morad, M. (1998) J. Clin. Invest. 101, 1385-1393). To investigate whether alterations in intracellular Ca(2+) trigger changes in the beta-adrenergic receptor pathway, we studied calsequestrin overexpressing transgenic mice at 7 and 14 weeks of age. As assessed by echocardiography, calsequestrin mice at 7 weeks showed mild left ventricular enlargement, mild decreased fractional shortening with increased wall thickness. By 14 weeks, the phenotype progressed to marked left ventricular enlargement and severely depressed systolic function. Cardiac catheterization in calsequestrin mice revealed markedly impaired beta-adrenergic receptor responsiveness in both 7- and 14- week mice. Biochemical analysis in 7- and 14-week mice showed a significant decrease in total beta-adrenergic receptor density, adenylyl cyclase activity, and the percent high affinity agonist binding, which was associated with increased beta-adrenergic receptor kinase 1 levels. Taken together, these data indicate that alterations in beta-adrenergic receptor signaling precede the development of overt heart failure in this mouse model of progressive cardiomyopathy.


Subject(s)
Calcium-Binding Proteins/genetics , Calsequestrin/genetics , Cardiomyopathy, Dilated/etiology , Receptors, Adrenergic, beta/metabolism , Age Factors , Animals , Cyclic AMP-Dependent Protein Kinases/metabolism , Disease Models, Animal , Down-Regulation , Echocardiography , Heart Function Tests , Heart Ventricles/pathology , Mice , Mice, Transgenic , Myocardial Contraction , Phenotype , Signal Transduction , Systole , beta-Adrenergic Receptor Kinases
15.
Circulation ; 99(20): 2702-7, 1999 May 25.
Article in English | MEDLINE | ID: mdl-10338466

ABSTRACT

BACKGROUND: Elevated circulating norepinephrine (NE) has been implicated in causing the profound beta-adrenergic receptor (betaAR) downregulation and receptor uncoupling that are characteristic of end-stage human dilated cardiomyopathy, a process mediated in part by increased levels of beta-adrenergic receptor kinase (betaARK1). To explore whether chronic sustained NE stimulation is a primary stimulus that promotes deterioration in cardiac signaling, we characterized a gene-targeted mouse in which activation of the sympathetic nervous system cannot lead to an elevation in plasma NE and epinephrine. METHODS AND RESULTS: Gene-targeted mice that lack dopamine beta-hydroxylase (dbh-/-), the enzyme needed to convert dopamine to NE, were created by homologous recombination. In vivo contractile response to the beta1AR agonist dobutamine, measured by a high-fidelity left ventricular micromanometer, was enhanced in mice lacking the dbh gene. In unloaded adult myocytes isolated from dbh-/- mice, basal contractility was significantly increased compared with control cells. Furthermore, the increase in betaAR responsiveness and enhanced cellular contractility were associated with a significant reduction in activity and protein level of betaARK1 and increased high-affinity agonist binding without changes in betaAR density or G-protein levels. CONCLUSIONS: Mice that lack the ability to generate NE or epinephrine show increased contractility associated primarily with a decrease in the level of betaARK1 protein and kinase activity. This animal model will be valuable in testing whether NE is required for the pathogenesis of heart failure through mating strategies that cross the dbh-/- mouse into genetically engineered models of heart failure.


Subject(s)
Cyclic AMP-Dependent Protein Kinases/metabolism , Epinephrine/deficiency , Myocardial Contraction/physiology , Norepinephrine/deficiency , Adrenergic beta-Agonists/pharmacology , Animals , Dobutamine/pharmacology , Dopamine beta-Hydroxylase/genetics , Female , GTP-Binding Proteins/metabolism , Gene Targeting , Hemodynamics/drug effects , Hemodynamics/physiology , Male , Mice , Mice, Mutant Strains , Myocardial Contraction/drug effects , Receptors, Adrenergic, beta/metabolism , Sarcolemma/metabolism , beta-Adrenergic Receptor Kinases
16.
J Biol Chem ; 272(34): 21253-9, 1997 Aug 22.
Article in English | MEDLINE | ID: mdl-9261135

ABSTRACT

Transgenic mice were generated with cardiac-specific overexpression of the wild-type (WT) alpha1B-adrenergic receptor (AR) using the murine alpha-myosin heavy chain gene promoter. Previously, we described transgenic mice with alpha-myosin heavy chain-directed expression of a constitutively active mutant alpha1B-AR that had a phenotype of myocardial hypertrophy (Milano, C. A., Dolber, P. C., Rockman, H. A., Bond, R. A., Venable M. E., Allen, L. F., and Lefkowitz, R. J. (1994) Proc. Natl. Acad. Sci. U. S. A. 91, 10109-10113). In animals with >40-fold WT alpha1-AR overexpression, basal myocardial diacylglycerol content was significantly increased, indicating enhanced alpha1-adrenergic signaling and phospholipase C activity. In contrast to the mice overexpressing constitutively active mutant alpha1B-ARs, the hearts of these mice did not develop cardiac hypertrophy despite an 8-fold increase in ventricular mRNA for atrial natriuretic factor. In vivo physiology was studied in anesthetized intact animals and showed left ventricular contractility in response to the beta-agonist isoproterenol to be significantly depressed in animals overexpressing WT alpha1B-ARs. Membranes purified from the hearts of WT alpha1BAR-overexpressing mice demonstrated significantly attenuated adenylyl cyclase activity basally and after stimulation with isoproterenol, norepinephrine, or phenylephrine. Interestingly, these in vitro changes in signaling were reversed after treating the mice with pertussis toxin, suggesting that the extraordinarily high levels of WT alpha1B-ARs can lead to coupling to pertussis toxin-sensitive G proteins. Another potential contributor to the observed decreased myocardial signaling and function could be enhanced beta-AR desensitization as beta-adrenergic receptor kinase (betaARK1) activity was found to be significantly elevated (>3-fold) in myocardial extracts isolated from WT alpha1B-AR-overexpressing mice. This type of altered signal transduction may become critical in disease conditions such as heart failure where betaARK1 levels are elevated and beta-ARs are down-regulated, leading to a higher percentage of cardiac alpha1-ARs. Thus, these mice serve as a unique experimental model to study the in vivo interactions between alpha- and beta-ARs in the heart.


Subject(s)
Myocardium/metabolism , Receptors, Adrenergic, alpha-1/metabolism , Receptors, Adrenergic, beta/metabolism , Adenylate Cyclase Toxin , Adenylyl Cyclases/metabolism , Animals , Atrial Natriuretic Factor/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Diglycerides/metabolism , GTP-Binding Proteins/metabolism , Mice , Mice, Transgenic , Myocardial Contraction , Pertussis Toxin , RNA, Messenger/metabolism , Sarcolemma/metabolism , Signal Transduction , Virulence Factors, Bordetella/pharmacology , beta-Adrenergic Receptor Kinases
18.
Psychopharmacol Bull ; 32(2): 253-7, 1996.
Article in English | MEDLINE | ID: mdl-8783895

ABSTRACT

As the prototypic "atypical neuroleptic," clozapine plays an increasingly important role in the treatment of refractory psychotic patients. However, little is known about the efficacy and safety of the compound for Asian patients. This study compares dosage, efficacy, and side-effect profiles in 17 Korean-American and 17 Caucasian age- and sex-matched schizophrenia or schizoaffective patients treated with clozapine. Asians showed a greater change than Caucasians in total scores of the 8-item Brief Psychiatric Rating Scale while receiving a significantly lower mean dose of clozapine (t = 2.48; p < .025). Furthermore, Asians had significantly lower mean clozapine concentrations than Caucasians and were significantly more likely to experience anticholinergic and other side effects. No serious untoward effects, such as agranulocytosis were reported in either group. These data suggest that Asians may be treated effectively and safely with lower doses of clozapine than those used for Caucasians.


Subject(s)
Clozapine/adverse effects , Clozapine/metabolism , Ethnicity , Adult , Asian , Female , Humans , Male , Middle Aged
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