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T Kadowaki

Publications and source records attributed to T Kadowaki.

At least 19 recordsLinked to original sources
PubMed2006

Japanese men have larger areas of visceral adipose tissue than Caucasian men in the same levels of waist circumference in a population-based study.

Visceral adipose tissue (VAT) is an independent risk factor for metabolic and cardiovascular disorders. There has been no study that demonstrated different abdominal fat distribution between Asian and Caucasian men. As the Japanese are less obese but more susceptible to metabolic disorders than Caucasians, they may have larger VAT than Caucasians at similar levels of obesity. We compared the abdominal fat distribution of the Japanese (n=239) and Caucasian-American (n=177) men aged 40-49 years in groups stratified by waist circumference in a population-based sample. We obtained computed tomography images and determined areas of VAT and subcutaneous adipose tissue (SAT). We calculated VAT to SAT ratio (VSR). The Japanese men had a larger VAT and VSR in each stratum, despite substantially less obesity overall. In multiethnic studies, difference in abdominal fat distribution should be considered in exploring factors related to obesity.

Adult↗
PubMed2006

Are comprehensive environmental changes as effective as health education for smoking cessation?

OBJECTIVES: To compare the effectiveness of health education on smoking cessation for all smokers regardless of their willingness to quit smoking and cumulative environmental changes including designation of smoking places, legislation, and price rise. DESIGN: Comparison of smoking cessation rates over two time periods: the period of health education on smoking cessation (1997-1999), and the period of cumulative environmental changes (2002-2004). SETTING: An occupational setting in a radiator manufacturing factory in Japan. SUBJECTS: All habitual male smokers who remained in the worksite through the pertinent time period (n = 202 in the period of health education and n = 170 in the period of environmental changes). MAIN OUTCOME MEASUREMENTS: Smoking cessation rates at the end of each time period. RESULTS: The smoking cessation rates over the periods of health education and environmental changes were 8.9% and 7.1%, respectively. There was no difference between these two proportions in a chi2 test (p = 0.513). The age adjustment did not significantly alter the cessation rate. CONCLUSIONS: Cumulative environmental changes are fairly effective in promoting smoking cessation, and may yield similar smoking cessation rates as a health education intervention reaching all smokers regardless of their willingness to quit smoking.

Adolescent↗
PubMed2006

Differential expression of peroxisome proliferator-activated receptor in histologically different human gastric cancer tissues.

Gastric cancer cell lines express peroxisome proliferator-activated receptor gamma (PPARgamma), and treatment with PPARgamma ligands suppresses growth of subgroup of these cell lines. However, expression and subcellular distribution of PPARgamma in human gastric cancer tissues is still unknown. Therefore, expression and subcellular localization of PPARgamma were examined among different histological types of gastric cancer tissues. Immunohistochemical staining for PPARgamma was performed using biopsy specimens of human gastric cancer of various histological types, gastric adenomas, and intestinal metaplasia. All samples of intestinal metaplasia and most samples of gastric tumors, except for signet ring cell carcinoma, expressed PPARgamma in the epithelial cells. Most samples of signet ring cell cancer lacked PPARgamma expression. All samples of intestinal metaplasia expressed PPARgamma only in the cytosol. For adenoma, 90% was positive for PPARgamma in cytosol, and 40% was positive in nuclei, for well-differentiated adenocarcinoma, 80% was positive in cytosol, and 20% was positive in nuclei. For moderately differentiated adenocarcinomas, 70% was positive for cytosol, and 80% was positive for nuclei; for poorly differentiated adenocarcinoma, 30% was positive in cytosol, and 70% was positive in nuclei. The frequency of samples with positive cytosolic staining decreased as the differentiation stage turned from intestinal metaplasia to adenoma, well-, moderately-, and poorly-differentiated cancers. Simultaneously, there was a tendency toward an increased frequency of samples with positive nuclear PPARgamma staining as the differentiation stage transformed from intestinal metaplasia to poorly-differentiated cancer. There was a striking difference in subcellular localization according to the differentiation levels of gastric dysplastic cells. The findings also supported an intestinal metaplasia-adenoma-well-differentiated gastric cancer sequence, and signet ring cell cancer was suggested to be of a different lineage from other types of gastric cancers.

Adenocarcinoma↗
PubMed2005

Absence of an association between the polymorphisms in the genes encoding adiponectin receptors and type 2 diabetes.

AIMS/HYPOTHESIS: Secreted by adipocytes, adiponectin is a hormone that acts as an antidiabetic and anti-atherogenic adipokine. We recently cloned the genes encoding two adiponectin receptors (ADIPOR1 and ADIPOR2). The aim of this study was to examine whether ADIPOR1 and/or ADIPOR2 play a major role in genetic susceptibility to insulin resistance or type 2 diabetes in the Japanese population. METHODS: By direct sequencing and a search of public databases, we identified single nucleotide polymorphisms (SNPs) in ADIPOR1 and ADIPOR2, and investigated whether these SNPs are associated with insulin resistance and type 2 diabetes in the Japanese population. RESULTS: The linkage disequilibrium (LD) in the chromosomal region of ADIPOR1 was almost completely preserved, whereas the LD in ADIPOR2 was less well preserved. None of the SNPs in ADIPOR1 or ADIPOR2 were significantly associated with insulin resistance or type 2 diabetes. No differences in ADIPOR1 or ADIPOR2 haplotype frequencies were observed between type 2 diabetic and non-diabetic subjects. CONCLUSIONS/INTERPRETATION: Genetic variations in ADIPOR1 or ADIPOR2 are unlikely to lead to a common genetic predisposition to insulin resistance or type 2 diabetes in the Japanese population.

Diabetes Mellitus, Type 2↗
PubMed2005

Hypoadiponectinaemia and high risk of type 2 diabetes are associated with adiponectin-encoding (ACDC) gene promoter variants in morbid obesity: evidence for a role of ACDC in diabesity.

AIMS/HYPOTHESIS: Morbid obesity (BMI>40 kg/m(2)) affecting 0.5-5% of the adult population worldwide is a major risk factor for type 2 diabetes. We aimed to elucidate the genetic bases of diabetes associated with obesity (diabesity), and to analyse the impact of corpulence on the effects of diabetes susceptibility genes. METHODS: We genotyped known single nucleotide polymorphisms (SNPs) in the adiponectin-encoding adipocyte C1q and collagen-domain-containing (ACDC) gene (-11,391G>A, -11,377C>G, +45T>G and +276G>T), the peroxisome proliferator-activated receptor gamma (PPARG) Pro12Ala SNP and ACDC exon 3 variants in 703 French morbidly obese subjects (BMI 47.6+/-7.4 kg/m(2)), 808 non-obese subjects (BMI<30 kg/m(2)) and 493 obese subjects (30< or =BMI<40 kg/m(2)). RESULTS: Two 5'-ACDC SNPs -11,391G>A, -11,377C>G were associated with adiponectin levels (p=0.0003, p=0.008) and defined a "low-level" haplotype associated with decreased adiponectin levels (p=0.0002) and insulin sensitivity (p=0.01) and with a risk of type 2 diabetes that was twice as high (p=0.002). In contrast, the prevalence of the PPARG Pro12Ala was identical in diabetic and normoglycaemic morbidly obese subjects. The PPARG Pro12 allele only displayed a trend of association with type 2 diabetes in the non-obese group. ACDC exon 3 variants were associated with type 2 diabetes in the non-obese group only (odds ratio 7.85, p<0.0001). In contrast, the 5'-ACDC "low-level" haplotype was associated with type 2 diabetes in obese and morbidly obese subjects (odds ratio 1.73 and 1.92) but not in non-obese individuals. CONCLUSIONS/INTERPRETATION: These data clarify the contribution of the 5'-ACDC SNPs to the risk of diabesity. Their interaction with corpulence suggests for the first time a different genetic profile of type 2 diabetes in morbidly obese patients compared with in less obese individuals.

Adiponectin↗
PubMed2005

What factors are associated with high plasma B-type natriuretic peptide levels in a general Japanese population?

There are few community-based epidemiologic studies that have dealt with risk factors for heart failure in non-Western populations. It has been reported that the measurement of plasma B-type natriuretic peptide (BNP) is useful for detecting patients with asymptomatic heart failure. To clarify the determinants of high plasma BNP level, the association of BNP with cardiovascular risk factors in community dwelling residents was examined. The plasma BNP levels were measured in 686 residents aged 35-69 years who received annual health check-up. The relationship of BNP to blood pressure, blood haemoglobin, serum cholesterol (total and high-density lipoprotein cholesterol), plasma glucose, electrocardiographic (ECG) findings, urinary salt excretion, and lifestyle factors (smoking and alcohol consumption) were cross-sectionally analysed. The plasma BNP geometric mean was 13.7 pg/ml. Both linear and logistic regression analyses indicated that the plasma BNP levels were positively associated with age, urinary salt excretion, higher blood pressure, high R-wave voltage in the 12-lead ECG (Minnesota Code 3-1 or 3-3), and female gender. Plasma BNP levels were inversely associated with blood haemoglobin levels. Gender-specific analysis showed similar results. However, plasma BNP did not correlate with other cardiovascular risk factors such as serum lipids.

Adult↗
PubMed2005

Different effects of blood pressure on mortality from stroke subtypes depending on BMI levels: a 19-year cohort study in the Japanese general population--NIPPON DATA80.

To evaluate the relationship between blood pressure and cerebrovascular death depending on body mass index (BMI) levels, we analysed a database of 9338 subjects from the National Integrated Project for Prospective Observation of Non-communicable Disease and its Trends in the Aged, which was originally conducted a baseline survey in 1980 and followed up in 1999. Relative risk (RR) and a 95% confidence interval (CI) of death from total stroke, cerebral infarction, and intracerebral haemorrhage after adjusting for age, sex, serum cholesterol, albumin, glucose, the use of antihypertensive agents, a past history of diabetes, BMI, smoking, and drinking were estimated with the Cox-proportional hazard model in the BMI tertile groups of a representative Japanese population. Cutoff points of BMI tertiles are 21.2 and 23.8 kg/m2. The results indicated that a 10 mmHg systolic blood pressure (SBP) increase was associated with mortality from intracerebral haemorrhage at low and middle BMI groups (RR= 1.38 and 1.23; 95% CI=1.17-1.62 and 1.03-1.47, respectively). SBP was positively associated with mortality from cerebral infarction in middle and high BMI groups (RR=1.19 and 1.21; 95% CI=1.06-1.33 and 1.06-1.38, respectively). The effects of diastolic blood pressure on intracerebral haemorrhage and infarction had the same tendency as those of SBP. These results suggested that the causal effect of blood pressure on stroke subtypes might be modified by BMI.

Adult↗
PubMed2005

Alcohol consumption and other risk factors for self-reported diabetes among middle-aged Japanese: a population-based prospective study in the JPHC study cohort I.

AIMS: Few prospective studies have examined the relationship between lifestyle characteristics and the incidence of diabetes mellitus in an Asian general population. This study was undertaken to evaluate the risk factors for Type 2 diabetes in a population-based prospective study of middle-aged Japanese. METHODS: We investigated 12,913 men and 15,980 women, aged 40-59 years at baseline (year 0), who participated in the Japan Public Health Center-based prospective study on cancer and cardiovascular diseases (JPHC Study) Cohort I. The participants were followed for up to 10 years. Incident cases of diabetes were identified by self-reporting of a physician's diagnosis on two questionnaires sent to each participant, one at year 5 and the second at year 10. RESULTS: During the 10-year follow-up, 703 men and 482 women reported newly diagnosed diabetes. Age, body mass index (BMI), family history of diabetes and cigarette smoking were independent risk factors in both genders by multivariate analysis. Among men with a BMI < or = 22 kg/m2, a significant positive association was observed between the diabetes incidence and moderate (23.0 < 46.0 g/day) to high (> 46.0 g/day) alcohol consumption, odds ratio 1.91 (95% CI, 1.05-3.46) and 2.89 (1.63-5.11), respectively. Among men with a BMI > 22 kg/m2, a small non-significant increase in odds ratio was observed with alcohol consumption. CONCLUSIONS: Established risk factors for diabetes in western populations were also identified as predictors of the disease among Japanese. Moderate to high alcohol consumption was positively associated with the incidence of diabetes in Japanese lean (BMI < or = 22 kg/m2) men.

Adult↗
PubMed2004

Specific alcoholic beverage and blood pressure in a middle-aged Japanese population: the High-risk and Population Strategy for Occupational Health Promotion (HIPOP-OHP) Study.

The purpose of this study was to clarify the effects of popular Japanese alcoholic beverages on blood pressure. We performed a cross-sectional study on 4335 Japanese male workers using baseline data from an intervention study. We defined six groups according to the type of alcoholic beverage that provided two-thirds of the subject's total alcohol consumption: beer, sake (rice wine), shochu (traditional Japanese spirits), whiskey, wine and others. The partial regression coefficients of daily alcohol intake (1 drink=11.5 g of ethanol) to systolic blood pressure (SBP) and diastolic blood pressure (DBP) were 0.87(P<0.001, standard error (s.e.)=0.09) and 0.77(P<0.001, s.e.=0.06), respectively. A comparison among the types of alcoholic beverages mainly consumed revealed significant differences in SBP and DBP. Both SBP and DBP were highest in the shochu group. However, an analysis of covariance adjusting for total alcohol consumption resulted in the disappearance of these differences. Although after adjustment for total alcohol consumption, the shochu group exhibited a significant positive association with 'high-normal blood pressure or greater' (odds ratio 1.43, 95% confidence interval 1.06-1.95) compared with the beer group, this significant relation disappeared after adjusting for the body mass index (BMI), urinary sodium and potassium excretion. The pressor effect, per se, of popular Japanese alcoholic beverages on blood pressure may not be different among the types of alcoholic beverages after adjusting for other lifestyle factors.

Adult↗
PubMed2004

The high-risk and population strategy for occupational health promotion (HIPOP-OHP) study: study design and cardiovascular risk factors at the baseline survey.

In order to establish the methodology of a population strategy for improving cardiovascular risk factors, we have planned the High-risk and Population Strategy for Occupational Health Promotion Study (HIPOP-OHP study). This study is a nonrandomized control trial in approximately 6500 participants in six intervention and six control companies. Our population strategy is based on three factors, nutrition, physical activity, and smoking. For each factor, a researcher's working team was organized and has been supporting the intervention. A standardized method to obtain comparable data has also been established. In the baseline survey, urinary sodium excretion in male subjects was higher, and urinary potassium excretion was lower in both genders in the intervention group compared to the control group. The prevalence of hypertension for both genders was also higher in the intervention group. Male subjects in the intervention group had higher serum total cholesterol than controls, while high-density lipoprotein cholesterol was lower in both genders in the intervention group compared to the control group. These differences were reflected by our finding that the predicted relative risk of coronary heart disease for male subjects was significantly higher in the intervention group (relative risk, RR: 1.17; 95% confidence interval, 95% CI.: 1.09, 1.25) and significantly lower in the control group (RR: 0.93; 95% CI.: 0.89, 0.98) compared to a model Japanese population. Similar results were observed in the female subjects. Taken together, these findings indicate that it is possible to compare trends of predicted relative risk for coronary heart disease between two groups.

Adult↗
PubMed2003

What cause of mortality can we predict by cholesterol screening in the Japanese general population?

OBJECTIVE: In a population with a markedly lower coronary mortality such as in Japan, the benefit of cholesterol screening may be different from Western populations. We attempted to assess the importance of cholesterol screening in Japan. DESIGN: A 13.2-year cohort study for cause-specific mortality. SETTING: Three hundred randomly selected districts throughout Japan in which the National Survey on Circulatory Disorders 1980 was performed. SUBJECTS: A total of 9216 community dwelling persons aged 30 years and over, with standardized serum cholesterol measurement and without a past history of cardiovascular disease. RESULTS: There were 1206 deaths, which included 462 deaths due to cardiovascular disease with 79 coronary heart diseases. Hypercholesterolemia (>6.21 mmol L-1) showed a significant positive relation to coronary mortality (relative risk; 2.93, 95% confidence interval; 1.52-5.63) but not to stroke. Although hypocholesterolemia (<4.14 mmol L-1) was significantly associated with an increased risk of liver cancer, noncardiovascular, noncancer disease and all-cause mortality, these associations, except for liver cancer, disappeared after excluding deaths in the first 5 years of the follow-up. The multivariate adjusted attributable risk of hypercholesterolaemia for coronary disease was 0.98 per 1000 person-years, which was threefold higher than that of hypocholesterolemia for liver cancer: 0.32 per 1000 person-years. The attributable risk percentage of hypercholesterolaemia was 66% for coronary heart disease. CONCLUSION: Similar to Western populations, it is recommended to provide screening for hypercholesterolaemia in Japan, especially for males, although its attributable risk for coronary disease might be small.

Adult↗
PubMed2002

Adiponectin stimulates glucose utilization and fatty-acid oxidation by activating AMP-activated protein kinase.

Adiponectin (Ad) is a hormone secreted by adipocytes that regulates energy homeostasis and glucose and lipid metabolism. However, the signaling pathways that mediate the metabolic effects of Ad remain poorly identified. Here we show that phosphorylation and activation of the 5'-AMP-activated protein kinase (AMPK) are stimulated with globular and full-length Ad in skeletal muscle and only with full-length Ad in the liver. In parallel with its activation of AMPK, Ad stimulates phosphorylation of acetyl coenzyme A carboxylase (ACC), fatty-acid oxidation, glucose uptake and lactate production in myocytes, phosphorylation of ACC and reduction of molecules involved in gluconeogenesis in the liver, and reduction of glucose levels in vivo. Blocking AMPK activation by dominant-negative mutant inhibits each of these effects, indicating that stimulation of glucose utilization and fatty-acid oxidation by Ad occurs through activation of AMPK. Our data may provide a novel paradigm that an adipocyte-derived antidiabetic hormone, Ad, activates AMPK, thereby directly regulating glucose metabolism and insulin sensitivity in vitro and in vivo.

Acetyl-CoA Carboxylase↗
PubMed2002

A genetic variation in the PGC-1 gene could confer insulin resistance and susceptibility to Type II diabetes.

AIMS/HYPOTHESIS: Peroxisome proliferator activated receptor gamma coactivator-1 (PGC-1), a transcriptional coactivator of the nuclear receptor PPARgamma, plays a role in adaptive thermogenesis and insulin sensitivity. Plasma fasting insulin has been linked to the chromosomal region where the PGC-1 gene is located. Thus, PGC-1 can be viewed as a functional and positional candidate for the susceptibility gene for Type II (non-insulin-dependent) diabetes mellitus. METHODS: After screening the PGC-1 gene for single nucleotide polymorphisms (SNPs), we performed an association study using the newly detected SNPs in 537 Type II diabetic patients and 417 non-diabetic subjects. RESULTS: We found three relatively frequent SNPs in the PGC-1 gene (IVS4-11T > C, Thr394Thr and Gly482Ser). There were significant differences in fasting insulin (Gly/Gly; 37.7 +/- 1.43, Gly/Ser; 40.2 +/- 1.21, Ser/Ser; 44.3 +/- 1.82 pmol/l, p = 0.018) and insulin resistance index (Gly/Gly; 1.48 +/- 0.06, Gly/Ser; 1.56 +/- 0.05, Ser/Ser; 1.75 +/- 0.08, p = 0.027) according to the genotype of the Gly482Ser polymorphism. The Thr394Thr - Gly482Ser haplotype was associated with Type II diabetes (p = 0.00003). CONCLUSION/INTERPRETATION. The results of this study suggested that the PGC-1 gene might be implicated in the pathogenesis of Type II diabetes.

Base Sequence↗
PubMed2002

A simple method to estimate populational 24-h urinary sodium and potassium excretion using a casual urine specimen.

In order to estimate the salt and potassium intake in a population and to compare their annual trends, we developed a simple method to estimate population mean levels of 24-h urinary sodium (24HUNaV) and potassium (24HUKV) excretion from spot urine specimens collected at any time. Using 591 Japanese data items from the INTERSALT study as a gold standard, we developed formulas to estimate 24-h urinary creatinine (24HUCrV), 24HUNaV and 24HUKV using both spot and 24-h urine collection samples. To examine the accuracy of the formulas, we applied these equations to 513 external manual workers. The obtained formulas were as follows: (1) PRCr (mg/day) = -2.04 x age + 14.89 x weight (kg) + 16.14 x height (cm) -2244.45; (2) estimated 24HUNaV (mEq/day) = 21.98 x XNa (0.392); (3) estimated 24HUKV (mEq/day) = 7.59 x XK(0.431); where PRCr = predicted value of 24HUCr, SUNa = Na concentration in the spot voiding urine, SUK = K concentration in the spot voiding urine, SUCr = creatinine concentration in the spot voiding urine, XNa (or XK) = SUNa (or SUK)/SUCr x PRCr. In the external group, there was a significant but small difference between the estimated and measured values in sodium (24.0 mmol/day) and potassium (3.8 mmol/day) excretion. In every quintile divided by the estimated 24HUNaV or 24HUKV, the measured values were parallel to the estimated values. In conclusion, although this method is not suitable for estimating individual Na and K excretion, these formulas are considered useful for estimating population mean levels of 24-h Na and K excretion, and are available for comparing different populations, as well as indicating annual trends of a particular population.

Adult↗
PubMed2001

Enhancement of the aquaporin adipose gene expression by a peroxisome proliferator-activated receptor gamma.

The current study demonstrates that aquaporin adipose (AQPap), an adipose-specific glycerol channel (Kishida, K., Kuriyama, H., Funahashi, T., Shimomura, I., Kihara, S., Ouchi, N., Nishida, M., Nishizawa, H., Matsuda, M., Takahashi, M., Hotta, K., Nakamura, T., Yamashita, S., Tochino, Y., and Matsuzawa, Y. (2000) J. Biol. Chem. 275, 20896-20902), is a target gene of peroxisome proliferator-activated receptor (PPAR) gamma. The AQPap mRNA amounts increased following the induction of PPARgamma in the differentiation of 3T3-L1 adipocytes. The AQPap mRNA in the adipose tissue increased when mice were treated with pioglitazone (PGZ), a synthetic PPARgamma ligand, and decreased in PPARgamma(+/-) heterozygous knockout mice. In 3T3-L1 adipocytes, PGZ augmented the AQPap mRNA expression and its promoter activity. Serial deletion of the promoter revealed the putative peroxisome proliferator-activated receptor response element (PPRE) at -93/-77. In 3T3-L1 preadipocytes, the expression of PPARgamma by transfection and PGZ activated the luciferase activity of the promoter containing the PPRE, whereas the PPRE-deleted mutant was not affected. The gel mobility shift assay showed the direct binding of PPARgamma-retinoid X receptor alpha complex to the PPRE. DeltaPPARgamma, which we generated as the dominant negative PPARgamma lacking the activation function-2 domain, suppressed the promoter activity in 3T3-L1 cells, dose-dependently. We conclude that AQPap is a novel adipose-specific target gene of PPARgamma through the binding of PPARgamma-retinoid X receptor complex to the PPRE region in its promoter.

3T3 Cells↗
PubMed2001

The loss of Drosophila APG4/AUT2 function modifies the phenotypes of cut and Notch signaling pathway mutants.

A P-element line ( P0997) of Drosophila melanogaster in which the P element disrupts the Drosophila homolog of the Saccharomyces cerevisiae gene APG4/AUT2 was identified during the course of screening for cut ( ct) modifiers. The yeast gene APG4/AUT2 encodes a cysteine endoprotease directed against Apg8/Aut7 and is necessary for autophagy. The P0997 mutation enhances the wing margin loss associated with ct mutations, and also modifies the wing and eye phenotypes of Notch (N), Serrate (Ser), Delta (Dl), Hairless (H), deltex (dx), vestigial (vg) and strawberry notch (sno) mutants. These results therefore suggest an unexpected link between autophagy and the Notch signaling pathway.

Amino Acid Sequence↗