The influence of blood glucose on neutrophil function in individuals without diabetes.

We assessed the association of neutrophil function with glycated hemoglobin (HbA1c) levels in a Japanese general population. Participants were 809 males and females who were over 20 years old living in the Iwaki region in Aomori Prefecture located in northern Japan. Lifestyle parameters (smoking, alcohol consumption, and exercise habits), HbA1c and neutrophil function such as reactive oxygen species (ROS) production capability and phagocytic activity (PA) were measured. ROS production capability was measured before and after phagocytic stimulus to obtain basal ROS production and stimulated ROS production. Level of HbA1c had a positive correlation with basal ROS production (p=0.053), a negative correlation with stimulated ROS production (p=0.072) and PA (p=0.059) only in post-menopausal groups, and not in pre-menopausal groups. However, there were no correlations between levels of HbA1c and neutrophil functions in male. In conclusion, in the present study, despite the presence of diabetes, chronic hyperglycemia was found to cause an increase in daily basal ROS production of neutrophils, and increased susceptibility to infection caused by reduced neutrophilic reaction in females in their menopause. Therefore, from the oxidative point of view, strict glycemic control is necessary to prevent post-menopausal females from developing diabetic complications in spite of the presence of diabetes.

Characteristics of reactive oxygen metabolites in serum of early teenagers in Japan.

OBJECTIVES: The relationship between the incidence of cardiovascular disease and the state of oxidative stress in blood has been studied to some extent. Several lines of evidence underscore the importance of primary prevention of cardiovascular disease beginning in childhood. However, little is known about the current state of oxidative stress in childhood. This study was carried out to determine the current state of the level of reactive oxygen metabolites (ROM) in serum of early teenagers. METHODS: This study enrolled 595 healthy junior high school students from the town of Nanbu located in northern Japan. Oxidative stress was evaluated by measuring the serum level of ROM, and antioxidant capacity was evaluated by measuring the serum level of biological antioxidant potential (BAP). RESULTS: Although the ROM level in female students [308.6 ± 63.1 Carratelli units (U.CARR)] was slightly higher than that in males (299.9 ± 55.2 U.CARR), the difference was not statistically significant. The BAP level in males was significantly higher than that in females. The levels of ROM and BAP detected in males in the first grade were higher than those in the other grades. In females, only first-graders' BAP was higher than that in other grades. CONCLUSIONS: The current study found that the ROM level in males was negatively correlated with grade. These results suggest the presence of factor(s) that increase oxidative stress in Japanese puberty.

Influence of obesity on blood pressure and arterial stiffness in the early teens.

PROBLEM: We studied the influence of adiposis on the progression of blood pressure and arteriosclerosis in the early teens. METHODS: The subjects of this study were 147 boys and girls (72 boys and 75 girls) in junior high school. Height, weight, percentage body fat, blood pressure, brachial-ankle pulse wave velocity (baPWV) and exercise time were measured. All subjects were measured at two points--at 5th grade in elementary school (ages between 10 and 11 years) and 2nd grade in junior high school (8th grade, ages between 13 and 14 years). The relationship between the change values of adiposis over 3 years (from 5th grade to 8th grade) and blood pressure/baPWV at the age of 13-14 were analyzed with multiple regression analysis. RESULTS: For boys, the change values in BMI and percentage body fat were correlated positively with systolic blood pressure. For girls, the change values in BMI and percentage body fat were correlated positively with systolic and diastolic blood pressures and baPWV. CONCLUSIONS: In conclusion, raised blood pressure was already observed in obese early teens as a result of arteriosclerosis progression regardless exercise habit, and it was more apparent in girls.

Differences in the influence of tobacco smoking on lung cancer between Japan and the USA: possible explanations for the 'smoking paradox' in Japan.

OBJECTIVES: The prevalence of cigarette smoking among Japanese men has been consistently high compared with males in Western countries over the past 30 years. However, during the same period, the incidence and mortality rates for lung cancer have been consistently lower in Japan than in Western countries, which has been termed the 'Japanese smoking paradox'. The odds ratio/relative risk of cigarette smoking for lung cancer mortality and incidence for the same number of cigarettes smoked per capita in Japan have been lower than those in Western countries. This difference in the odds ratio/relative risk is likely to be the main reason for the Japanese smoking paradox. The aim of this study was to clarify the reason for the difference in the odds ratio/relative risk between Japan and the USA. STUDY DESIGN: Literature review to compare environmental, hereditary and other factors that may be related to lung cancer in Japan and the USA. RESULTS AND CONCLUSIONS: The main factors likely to have brought about the difference in the odds ratio/relative risk between Japan and the USA (and perhaps other Western countries as well) are: lower alcohol consumption by Japanese males; lower fat intake by Japanese males; higher efficiency of filters on Japanese cigarettes; lower levels of carcinogenic ingredients in Japanese cigarettes; and lung-cancer-resistant hereditary factors among Japanese males.