Masao Yoshida

Mitochondrial DNA 5178 (Mt5178) C/A polymorphism is reportedly associated with longevity in the Japanese population. The objective of this study was to investigate whether Mt5178 C/A polymorphism influences the effect of physiological aging on renal function in male Japanese health checkup examinees. A total of 404 male subjects (mean age ± SD, 53.9 ± 7.8 years; range, 29–76 years) were selected from among individuals visiting the hospital for regular medical checkups. After Mt5178 C/A genotyping, a cross-sectional study assessing the joint effects of Mt5178 C/A polymorphism and aging on renal function was then conducted. Renal function was evaluated by estimated glomerular filtration rate (eGFR). Subjects were divided into three age groups (< 50, 50–59, ≥ 60 years). In simple linear regression analysis, a significant negative association between aging and eGFR was observed in both Mt5178C and Mt5178A genotypic men (P < 0.001 and P = 0.003, respectively). However, in multiple linear regression analysis, a significant effect of aging on reduced eGFR was observed only in Mt5178C genotypic men (P < 0.001). Logistic regression analysis showed that, in the case of reduced eGFR defined as < 75 mL/min/1.73 m2, reduced eGFR was dependent on aging in both Mt5178C and Mt5178A genotypic men (P for trend < 0.001 and P for trend = 0.002, respectively). After adjusting for smoking status and alcohol consumption, reduced eGFR was also dependent on aging in both Mt5178C and Mt5178A genotypic men (P for trend < 0.001 and P for trend = 0.014, respectively). However, in reduced eGFR defined as < 90 mL/min/1.73 m2, reduced eGFR was dependent on aging only in Mt5178C genotypic men (P for trend < 0.001). This cross-sectional study suggests that Mt5178 C/A polymorphism modulates the effects of physiological aging on kidney function in Japanese men.

Background: Nicotinamide adenine dinucleotide (NADH) dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism has been shown to modify the association of coffee consumption with the risk of hypertension, dyslipidemia, and abnormal glucose tolerance, and low serum chloride levels have been shown to be associated with all-cause and cardiovascular disease mortality. Therefore, the purpose of the present study was to investigate whether ND2-237 Leu/Met polymorphism influences the association of coffee consumption with serum chloride levels in male Japanese health checkup examinees. Methods: From among individuals visiting the hospital for a regular medical checkup, 402 men (mean age ± standard deviation, 53.9 ± 7.8 years) were selected for inclusion in the study. After ND2-237 Leu/Met genotyping, we conducted an exploratory cross-sectional study to examine the combined association of ND2-237 Leu/Met polymorphism and coffee consumption with serum electrolyte levels. Results: After adjusting for age, body mass index, habitual smoking, alcohol consumption, green tea consumption, and antihypertensive medication, coffee consumption significantly increased serum chloride levels (p for trend = 0.001) in men with the ND2-237Leu genotype. After these adjustments, the odds ratios (ORs) for low levels of serum chloride, defined as p for trend = 0.001). In addition, the OR for low levels of serum chloride was significantly lower in men with the ND2-237Leu genotype who consumed ≥4 compared with p = 0.044). However, neither serum chloride levels nor risk of low levels of serum chloride appeared to be dependent on coffee consumption. Conclusions: The results suggest that ND2-237 Leu/Met polymorphism modifies the association of coffee consumption with serum chloride levels in middle-aged Japanese men.

Mitochondrial DNA 5178 cytosine/adenine (Mt5178 C/A) polymorphism reportedly modulates the effects of coffee consumption on the risk of hypertension, dyslipidemia and abnormal glucose tolerance. The objective of this analysis was to investigate whether Mt5178 C/A polymorphism modifies the effects of coffee consumption on erythrocytic parameters in male Japanese health check-up examinees.

Longevity-associated mitochondrial DNA 5178 (Mt5178) C/A reportedly modulates the effects of coffee consumption on the risk of hypertension, dyslipidemia and abnormal glucose tolerance, and those of alcohol consumption on the risk of hypertension, dyslipidemia and hyperuricemia in middle-aged Japanese men. However, there has been no research examining whether Mt5178 C/A polymorphism influences the effects of coffee consumption or alcohol consumption on the clustering of cardiovascular risk factors (CRFs). A total of 332 male subjects (mean age ± SD, 52.8 ± 7.8 years) were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, a cross-sectional study assessing the joint effects of Mt5178 C/A polymorphism and coffee consumption or alcohol consumption on the clustering of CRFs, namely hypertension, abnormal glucose tolerance, hyper-low-density lipoprotein cholesterolemia, hypo-high density lipoprotein cholesterolemia, hypertriglyceridemia and hyperuricemia, was then conducted. After adjustment for confounding factors, significant and negative associations were observed between coffee consumption and clustering of ≥2 CRFs in subjects with Mt5178C. The adjusted odds ratio (OR) for the clustering of ≥2 or ≥3 CRFs was significantly lower in subjects who consumed 1-3 cups of coffee per day than in those who consumed <1 cup of coffee per day (OR = 0.496, 95% confidence interval (CI): 0.249-0.989, and OR = 0.369, 95% CI: 0.165-0.826, respectively). On the other hand, after adjustment, positive associations between coffee consumption and clustering of ≥2 CRFs were observed in subjects with Mt5178A. However, these associations did not reach a significant level. For Mt5178C genotypic men, the adjusted OR for the clustering of ≥2 or ≥3 CRFs was significantly higher in daily drinkers than in occasional drinkers (OR = 2.737, 95% CI: 1.361-5.502, and OR = 3.024, 95% CI: 1.269-7.210, respectively). On the other hand, the association between Mt5178A genotype and the clustering of ≥2 or ≥3 CRFs did not appear to depend on alcohol consumption. The present results suggest that Mt5178 C/A polymorphism modifies the effects of coffee consumption or alcohol consumption on the clustering of CRFs in middle-aged Japanese men.

Mitochondrial DNA 5178 cytosine/adenosine (Mt5178 C/A) polymorphism is associated with longevity in the Japanese. The purpose of this study is to investigate whether Mt5178 C/A polymorphism modifies the effects of habitual smoking or habitual drinking on serum non-high-density lipoprotein (non-HDL) cholesterol levels in middle-aged Japanese men.

NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism reportedly influences the effects of cigarette smoking on respiratory function, risk of dyslipidemia, serum non-high-density lipoprotein cholesterol levels, hematological parameters and intraocular pressure. The objective of this study was to investigate whether ND2-237 Leu/Met polymorphism modifies the effects of cigarette smoking on serum liver enzyme levels in male Japanese health check-up examinees.

NADH dehydrogenase subunit-2 237 leucine/methionine (ND2-237 Leu/Met) polymorphism is associated with longevity in Japanese. A previous study has shown that ND2-237 Leu/Met polymorphism modulates the effects of green tea consumption on risk of hypertension. For men with ND2-237Leu, habitual green tea consumption may reduce the risk of hypertension. Moreover, there is a combined effect of ND2-237 Leu/Met polymorphism and alcohol consumption on risk of mildly decreased estimated glomerular filtration rate (eGFR) (<90 ml/min/1.73 m2). Several beneficial effects of green tea on the kidney have been reported. The objective of this study was to investigate whether ND2-237 Leu/Met polymorphism modifies the effects of green tea consumption on risk of mildly decreased eGFR in male Japanese health check-up examinees.

Objectives To clarify whether smoking was associated with elevated intraocular pressure (IOP) and to evaluate the interrelationship among IOP, blood viscosity, and smoking. Methods This cross-sectional study analyzed health examination data obtained between 2001 and 2004 from 1113 individuals (829 men and 284 women), ranging in age from 28 to 79 years, who had not undergone any ocular surgery or medical treatment for hypertension, ocular hypertension, and glaucoma. Results Multiple-regression analysis showed that systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), and number of cigarettes smoked per day had a significantly positive association with IOP in men (P < 0.05). In women also, SBP, DBP, and BMI were positively related to IOP (P < 0.05). On the contrary, age had a significant negative association with IOP in both sexes (P < 0.01). Analysis of covariance and multiple logistic regression analyses showed that the adjusted mean IOP and the multivariate odds ratios for IOP increased with increasing cigarette consumption in men (P for trend = 0.01 and 0.06, respectively). Analysis of covariance found that smoking was significantly associated with both high IOP and high hematocrit in men (P for trend <0.05); however, the adjusted mean IOP values were higher in smokers than in nonsmokers, regardless of the hematocrit level. Conclusions The results of this study suggested that the IOP level may be substantially affected by smoking habit in middle-aged and older Japanese men.

Prevention of chronic kidney disease (CKD) is a major public health issue. Although several studies have been performed on the association between alcohol consumption and CKD or renal function, it remains controversial. Numerous genetic polymorphisms have been reported to be associated with CKD and kidney function. Mitochondrial DNA cytosine/adenine (Mt5178 C/A) polymorphism is associated with longevity in Japanese. This polymorphism modifies the effects of alcohol consumption on blood pressure, risk of hypertension, serum triglyceride levels, risk of hyper-LDL cholesterolemia and serum uric acid levels. The objective of this study was to investigate whether Mt5178 C/A polymorphism modifies the effects of alcohol consumption on renal function in male Japanese health check-up examinees.

Several genetic polymorphisms have been reported to modify the effects of smoking on serum lipid levels. The objective of this study was to investigate whether longevity-associated mitochondrial DNA 5178 (Mt5178) C/A polymorphism modifies the effects of habitual smoking on the risk of dyslipidemia in middle-aged Japanese subjects. A total of 394 male subjects (age, 53.9 ± 7.9 years; mean ± SD) were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, a cross-sectional study assessing the joint effect of Mt5178 C/A polymorphism and cigarette smoking on the risk of hypo-high-density lipoprotein (HDL) cholesterolemia, hyper-low-density lipoprotein (LDL) cholesterolemia or hypertriglyceridemia was conducted. For subjects with Mt5178C, the risk of hypo-HDL cholesterolemia increased with the number of cigarettes smoked daily (P for trend = 0.001). On the other hand, the association between Mt5178A genotype and the risk of hypo-HDL cholesterolemia did not appear to depend on the number of cigarettes smoked daily. For those with Mt5178A, the risk of hyper-LDL cholesterolemia or hypertriglyceridemia increased with cigarettes smoked daily (P for trend = 0.017 and P for trend = 0.002, respectively). However, the association between Mt5178C genotype and the risk of hyper-LDL cholesterolemia or hypertriglyceridemia did not depend on the number of cigarettes smoked daily. The present results suggest that Mt5178 C/A polymorphism modulates the effects of habitual smoking on the risk of dyslipidemia in middle-aged Japanese men.