Kazuhiko Kotani

The relationship between usual coffee consumption and serum C-reactive protein level in a Japanese female population.

Abstract Background: Usual coffee consumption may decrease insulin resistance and type 2 diabetes incidence, and reduce cardiovascular disease risk. As a mechanism, coffee-induced lower levels of C-reactive protein (CRP), a marker for the development of these diseases, can be considered. The associations between coffee consumption and CRP should be established by studies on various populations, yet studies in Japanese people, who do not necessarily consume as much coffee daily, are limited. Methods: In total, 459 community-living Japanese women, aged 23–83 years, were investigated. Clinical data including age, body mass index, blood pressure, HbA1c, serum high sensitive CRP (hsCRP) and lifestyle habits, such as coffee consumption, were included in the analyses. All analyses were performed in two groups of the population, i.e., age <60 and ≥60 years. Results: Significantly lower levels of hsCRP were observed in the group of ≥1 cup/day than in that of <1 cup/day in the respective groups of <60 years (p=0.001) and ≥60 years (p<0.0001). In multiple regression analysis, coffee consumption was significantly, independently and inversely correlated to log-hsCRP in the respective groups of <60 years (p=0.017) and ≥60 years (p<0.0001). Conclusions: It was noteworthy that the benefits of coffee consumption, even if ≥1 cup/day, on serum hsCRP levels were confirmed in Japanese women, following similarly to other ethnic data. Clin Chem Lab Med 2008;46:1434–7.

The association of the Clock 3111 T/C SNP with lipids and lipoproteins including small dense low-density lipoprotein: results from the Mima study

BackgroundThe clock molecule plays major roles in circadian rhythmicity and regulating lipid and glucose metabolism in peripheral organs. Disruption of the circadian rhythm can lead to cardiometabolic disorders. The existence of small dense low-density lipoprotein (sdLDL) in the circulation, an abnormality of lipid metabolism, in part associated with lifestyle, is also one of risk parameters for cardiometabolic disorders. The 3111 T/C single nucleotide polymorphism (SNP) of the Clock gene has been reported to be associated with lifestyle including morning/evening preference. We investigated whether the Clock 3111 T/C SNP may affect lipids and lipoproteins including sdLDL.MethodsIn 365 community-dwelling subjects (170 men and 195 women, mean age 63 ± 14 years), the 3111 T/C SNP was genotyped using a fluorescent allele-specific DNA primer assay system. The levels of sdLDL were measured with the electrophoretic separation of lipoproteins employing the Lipoprint system.ResultsThe frequency of the Clock 3111 C allele was 0.14. The area of sdLDL did not differ between the subjects with obesity and those without. In carriers of T/T homozygotes, the area of sdLDL was significantly higher compared with carriers of the C allele (T/C or C/C) (1.7 ± 3.4 vs. 0.8 ± 1.9%; p < 0.05). A multiple regression analysis showed that the area of sdLDL was significantly and negatively correlated with the Clock 3111 T/C SNP (β = -0.114, p < 0.05), independently of age, sex, body mass index, and exercise habits.ConclusionOur findings indicated that the Clock 3111 T/C SNP might be associated with the existence of sdLDL.

The common −55 C/T polymorphism in the promoter region of the uncoupling protein 3 gene reduces prevalence of obesity and elevates serum high-density lipoprotein cholesterol levels in the general Japanese population

Uncoupling protein 3 (UCP3) is considered to be associated with obesity, given its function in the regulation of energy and lipid metabolism. An increased body mass index (BMI) and a decreased level of high-density lipoprotein cholesterol (HDL-C) are risk factors for cardiovascular disease. The purpose of this study was to investigate whether the UCP3 promoter -55 C/T single nucleotide polymorphism (UCP3 -55 C/T SNP) was associated with obesity according to the criteria for Japanese (BMI > or = 25 kg/m2), BMI, and serum HDL-C levels in the general Japanese population. The subjects, numbering 282 and aged 65 +/- 13 years (mean +/- SD), were recruited through an annual health checkup of residents of Mima city, Tokushima, in Japan. Body mass index, blood pressure, biochemical indexes including lipid, and lipoprotein profiles were measured. The UCP3 -55 C/T SNP was determined with a fluorescence-based allele-specific DNA primer assay system. The frequency of the -55 T allele was 30.0%. Subjects with the T/T genotype had significantly higher HDL-C levels than those with the C/C genotype or the C/T genotype. Furthermore, subjects with the T/T genotype had a significantly lower BMI than those with the C/C genotype. A multivariate analysis revealed that the -55 T allele was a significant independent variable contributing to the variance in HDL-C levels and BMI. The T/T genotype was associated with a lower prevalence of obesity than the C/C and C/T genotypes, with an odds ratio of 0.358 (95% confidence interval, 0.132-0.972; P = .037). In conclusion, the UCP3 -55 C/T SNP was associated with elevated HDL-C levels and a reduced BMI, independent of modifiable factors such as lifestyle. Furthermore, this polymorphism, when expressed in its homozygous form, reduced the prevalence of obesity in Japanese.

Serum adiponectin levels and lifestyle factors in Japanese men

Adiponectin plays an important role in the development of various lifestyle-related diseases such as obesity, hypertension, type II diabetes mellitus, hyperlipidemia, and metabolic syndrome, leading to the development of heart and vascular diseases. However, the determinants that affect circulating adiponectin levels, including lifestyle factors, have still not been thoroughly investigated, in a general male population in particular. A total of 109 healthy Japanese male subjects (mean age, 55 ± 14 years) with constant lifestyles were enrolled. All were on no medication. Fasting serum adiponectin levels were measured with an enzyme-linked immunosorbent assay. Each subjects lifestyle was assessed by the self-administered Breslow Questionnaire (a well-established method to estimate various lifestyles) with minor modifications. Partial correlation analysis for serum adiponectin levels, after controlling age and all lifestyle factors, revealed a significant and independent negative correlation between serum adiponectin levels and body mass index (BMI) (r = −0.222, P = 0.025), and a significant and independent positive correlation between serum adiponectin levels and sleep duration (r = 0.252, P = 0.011). No significant correlations were observed between adiponectin and other lifestyle factors. These data suggest that increased BMI and shorter sleep duration may be significant independent risks for low serum adiponectin levels in healthy males. Therefore, these factors may be intervention targets to modulate adiponectin to its proper levels for the prevention of cardiovascular disorders.

Clustered components of the metabolic syndrome and platelet counts in Japanese females

Abstract Background: Blood platelet counts (PCs) play a role in the development of cardiovascular disease (CVD). The metabolic syndrome (MS) is also associated with high CVD risk. However, the connection between PCs and MS has not yet been thoroughly investigated in relation to various biosocial factors that can affect both PCs and the pathophysiology of MS. Methods: A total of 152 asymptomatic female subjects (mean age 50 years) with almost normal levels of hemoglobin and white blood cell counts were recruited. MS was diagnosed according to the NCEP-ATP III criteria with a minor modification. The relationships between PCs and MS were analyzed according to the number of MS components (0, 1–2, ≥3). Biosocial factors including age and some lifestyle factors (smoking, alcohol intake and physical activity) were included in the analyses. Results: PCs in subjects with ≥3 MS components (233±43 [SD]×109 /L) were strikingly and significantly higher than in subjects with 0 (194±34×109/L) or 1–2 MS components (207±38×109/L). General linear model analysis for PCs, adjusted for all biosocial factors and number of MS components, revealed a significant and positive correlation between PCs and number of MS components (p<0.0001). Conclusions: The results suggest that PCs may be a potential marker associated with clustered MS components, independent of some biosocial factors, in Japanese females. Clin Chem Lab Med 2007;45:376–9.

Lifestyles and oxidative stress in type 2 diabetic patients.

Kazuhiko Kotani, Naoki Sakane, Kokoro Tsuzaki, Yukiyo Matsuoka, Yoshiko Sano, Taku Hamada and Kazunori Yamada Division of Preventive Medicine and Diabetes Education, Clinical Research Institute for Endocrine and Metabolic Disease, National Hospital Organization Kyoto Medical Center, Kyoto, Japan; Division of Health Administration and Promotion, Faculty of Medicine, Tottori University, Tottori, Japan; Center for Diabetes, National Hospital Organization Kyoto Medical Center, Kyoto, Japan

The angiotensin II type 2 receptor gene polymorphism and body mass index in healthy Japanese women

Background: Angiotensin II (AngII), through the AngII type 2 receptor (AT2-R), might exert some effect on adipocyte-and lipogenesis-related biology. The Adenine/Cytosine 3123 (A/C3123) polymorphism in the AT2-R gene is reportedly involved in some diseases, such as hypertension. Methods: A total of 201 healthy Japanese women (mean age 43.2 years) were enrolled in the study to investigate the association among the AT2-R A/C3123 polymorphism detected by polymerase chain reaction methods, body mass index (BMI) and other obesity-linked metabolic parameters (blood pressure, serum lipid/lipoprotein, plasma glucose). Results: Homozygotes of the C-allele in the AT2-R A/C3123 polymorphism were associated with small but significant increases in BMI levels. There were no differences between genotype-based groups in the obesity-linked metabolic parameters. Conclusion: These findings suggest that the AT2-R A/C3123 polymorphism could be a polymorphic marker related to BMI in Japanese women.

Dietary salt reduction in rural patients with albuminurea using family and community support: the Mima study

BackgroundResidents of rural communities are often more socially connected compared to urban dwellers. Using family and community support to motivate health behavior change may be useful in rural settings. The objective of this study was to pilot a salt reduction (SR) intervention for rural albuminuria patients using support from family and neighborhood residents compared to a usual care condition. The primary outcome was change in urine albumin-creatinine ratio (ACR).MethodsAll consecutive outpatients with an ACR >= 30 mg/gCr were recruited from the Koyadaira Clinic. Patients self-selected their participation in the intervention group (IG) or the control group (CG) because the rural population expressed concern about not being treated at the same time. In the IG, patients and their families were educated in SR for 30 minutes in their home by experienced dieticians. In addition, patients, families and neighborhood residents were also educated in SR for 2 hours at a public town meeting hall, with educational content encouraging reduction in salt intake through interactive activity. The CG received conventional treatment, and ACR and blood pressure (BP) were measured after 3 months.ResultsOf the 37 subjects recruited (20 male, 16 female, mean age; 72.8 ± 9.2 years), 36 completed the 3-month follow up and were analyzed. In the IG, ACR decreased significantly from baseline (706 ± 1,081 to 440 ± 656; t = 2.28, p = 0.04) and was reduced compared to the CG (213 ± 323 to 164 ± 162; F = 3.50, p = 0.07), a treatment effect approaching significance. Systolic BP in the IG (145 ± 14 to 131 ± 13 mmHg; t = 3.83, p = 0.002) also decreased significantly compared to the CG (135 ± 13 to 131 ± 14; F = 4.40, p = 0.04).ConclusionsSimultaneous education of patients, their families and neighborhood residents may be important in rural areas for treatments and interventions requiring health behavior change.Trial registrationUMIN000001972

The uncoupling protein-1 gene -3826A/G polymorphism and hypertension in Japanese subjects.

Abstract Background: The possible effects of the uncoupling protein-1 (UCP-1) gene −3826A/G polymorphism on hypertension (HT) have yet to be elucidated. Methods: A total of 578 Japanese subjects (231 males and 347 females, mean age 58.4 years) were enrolled in the study to investigate the association between HT and the −3826A/G polymorphism by genomic PCR and Bcl1-restriction fragment length polymorphism methods. Results: Multivariate logistic regression analysis for HT, adjusted for genotype (recessive model, AA+AG vs. GG) and other covariates such as cardiovascular risk factors [e.g., smoking, body mass index (BMI), dyslipidemia and diabetes] showed age [odds ratio (OR) 1.11 (95% confidence interval 1.08–1.13)] and BMI [OR 1.13 (1.06–1.21)] as independent significant factors. In the subgroup analysis, as well as age and BMI, GG genotype [OR 2.32 (1.08–4.99)] was also an independent significant factor for HT in males. Similarly, as well as age and BMI, GG genotype [OR 1.89 (1.00–3.57)] was also an independent significant factor for HT in the relatively older subgroup (≥60 years). Conclusions: The results suggest that the GG genotype may be associated with the presence of HT in Japanese males and older subjects. Further investigation is needed to confirm our hypothesis. Clin Chem Lab Med 2007;45:1186–9.