Impact of annual body mass index gain on obesity development in Japanese 6-year-old non-obese children.

BACKGROUND: Effective timing of preventive intervention for adolescent obesity in non-obese school-aged children remains unclear. The aim of this study was to examine the impact of annual body mass index (BMI) gain on the development of adolescent obesity in 6-year-old non-obese Japanese children. METHODS: Longitudinal weight and height data were collected annually from 9723 children aged 6-14 years, and individual per-year BMI gains were calculated. The BMI ≥ the 95th percentile for each age and sex defined obesity. In 6-year-old non-obese children, logistic regression analyses were applied to correlate the annual BMI gain at each age with obesity at a final survey. RESULTS: The 6-year-old non-obese children who became obese at a final survey showed larger annual BMI gains at any age compared with their peers with respect to baseline BMI. Increases in annual BMI gain, even in early school age, raised the risk of adolescent obesity. Categorical analysis also showed that children aged 6-7 years with higher annual BMI gains than 1-SD above the mean had a significant risk for adolescent obesity (OR: 4.39 [95%CI: 2.98-6.46] in boys and 3.83 [95%CI: 2.60-5.63] in girls, respectively). CONCLUSIONS: A larger annual BMI gain at any school age is a risk for adolescent obesity in 6-year-old non-obese children with no critical period. This suggests the need for earlier and continuous school-based surveillance using annual BMI gain for preventive intervention of adolescent obesity development.

Plasma dipeptidyl peptidase 4 activity correlates with body mass index and the plasma adiponectin concentration in healthy young people.

We previously found that plasma dipeptidyl peptidase 4 (DPP4) activity was associated with the development of obesity, type 2 diabetes, and type 1 diabetes using animal models. In this study, we investigated whether DPP4 activity is correlated with the clinical parameters of obesity and/or diabetes in healthy young subjects. Body mass index (BMI), plasma DPP4 activity, total cholesterol, high density lipoprotein (HDL) cholesterol, triglycerides, fasting blood glucose, adiponectin concentration, and body fat were measured in 165 subjects (110 males and 55 females, age 23.2 ± 2.4 years). In correlation analyses, DPP4 activity displayed strong positive correlations with BMI (p = 5.5 × 10(-5)) and total cholesterol (p = 0.0014), and a negative correlation with the plasma adiponectin concentration (p = 0.013), but not fasting blood glucose. Our findings suggest that plasma DPP4 activity is correlated with the clinical parameters of obesity rather than diabetes in young people.

Climatic influence on the reproductive characteristics of Japanese males.

We previously performed a survey of the sperm characteristics of the partners of pregnant women in four cities in Japan. In the present study, we analyzed the sperm characteristics of these subjects and the correlations between these sperm characteristics and climatic changes or Y chromosome haplogroups. Our results showed that more haplogroup D2a1 males than O2b1 males were born in the first half of the year (January to June), whereas more O2b1 males were born in the last half of the year (July to December) (P<0.05). This was agreed and correlated with the seasonal variations in their mean sperm concentrations. The haplogroup C, D* and D2a1 males displayed lower sperm concentrations from March to May, followed by an increase in their sperm concentrations starting in June or July, while the O2b1 males displayed higher sperm concentrations in the first half of the year followed by a sudden decrease from July to August (P<0.05). We hypothesize that the Japanese climate has different effects on the sperm characteristics and reproductive seasonality of males from different lineages; and therefore, has influenced the modern population of Japan.

Proteasome activity correlates with male BMI and contributes to the differentiation of adipocyte in hADSC.

We have previously reported that 26S proteasome subunit mRNA expressions correlate with male body mass index (BMI). In this study, to investigate whether proteasome activities are correlated with BMI, we recruited 61 healthy young Japanese male subjects, measured proteasome activities in their plasma, and correlated them with their BMI and various metabolic factors. We found that among three different proteasome activities, chymotrypsin-like activity in plasma was positively correlated with BMI in healthy Japanese male subjects. Furthermore, we analyzed proteasome activity in vitro during the differentiation of human adipose-derived stem cell (hADSC) into mature adipocytes. In the early stage of differentiation, proteasome activity was at its highest level, and proteasome inhibitor could inhibit hADSC adipocyte differentiation. Our findings suggest that proteasome is an important controlling factor for the development of obesity and adipogenesis.

Prediction of Japanese children at risk for complications of childhood obesity: gender differences for intervention approaches.

Childhood obesity is one of the most serious public health problems in Japan, especially in Tokushima compared with other prefectures. This study was designed to clarify the life habits which predispose to development of obesity and can be modified through an appropriate intervention program to combat childhood obesity and its lifestyle-related diseases. A total of 216 school children from Itano Town, a municipality of Tokushima Prefecture, Japan, who are attending the fourth grade (9-10 years) of elementary schools, participated in the study from 2004 to 2007. The study included child's life habits questionnaire, investigating physical activity by recording the daily steps using a pedometer, anthropometric measurements, hematological examination and hemodynamometry in a cross-sectional survey during a two-month period from June to July every year. We conclude that there are considerable gender-related differences for developing obesity and other lifestyle-related diseases; and all intervention strategies against obesity must consider such gender differences. For example, restriction of television watching hours must be intervened for controlling obesity in boys, however for girls, promotion of exercise practice or making more steps per day with adequate sleeping periods should be intervened as the proper approaches for preventing and controlling obesity and other lifestyle-related diseases.

Determinants of life satisfaction among Japanese elderly women attending health care and welfare service facilities.

Prolonged life expectancy must be recognized as an excellent achievement of modern medicine, but not all the elderly people are satisfied with their lives. Life satisfaction is a multi-dimensional issue that depends on many objective and subjective characteristics. In this study, we aimed at investigating the factors affecting life satisfaction of 314 elderly Japanese women attending in 28 elderly-care and welfare facilities at Tokushima Prefecture, Japan. Our results indicated that elderly subjects with depression tendencies always show significantly lower degrees of life satisfaction than others who are not depressed (p<0.001) regardless of their cognitive status. Furthermore, elderly women who shared decision for their living place and whose opinions were considered for daily life decisions reported significantly more life satisfaction levels than others. We conclude that elderly life satisfaction is affected by various determinants however, with different influencing weight. Life satisfaction of elderly people, with or without dementia, is greatly affected by their mood status and share in decision making. Avoiding elderly people depressive mood, sharing them in various daily decisions, considering their opinions, and allowing them to decide their elderly-care facility placement are crucial determinants for their life satisfaction and essential for their coping, adaptation, well-being and successful aging.

Weight and height growth velocities of Japanese boys and girls between age 7 and 14 years: a critical window for early adolescent overweight risk.

Childhood overweight is an important worldwide problem of public health concern, with metabolic, physical and psychosocial complications. More and more evidence is accumulating that children who gain weight rapidly earlier in life are at higher risk of becoming overweight later in adulthood life. Therefore, in a seven-year longitudinal study, we studied mid-childhood and early adolescence weight and height growth velocities among 5,024 Japanese 2(nd) grade primary school boys and girls along with its effect on the likelihood of being overweight adolescents by the age of 14 y. Our findings showed that weight growth velocity of both sexes was associated with being overweight at the end of longitudinal study. Boys' risk of accelerated weight growth velocity and becoming overweight adolescents was almost doubled during ages 7 approximately 11 y and become reduced afterward. Otherwise, odds ratios of girls' weight growth velocity peaks were found only at ages from 9 approximately 10 and 10 approximately 11 y. Thus, we suggest a critical window of mid-childhood period associated with adolescence risk of overweight, and we recommend that studying weight growth determinants during 7 approximately 11 y of boys and 9 approximately 11 y of girls may help in developing and applying proper programs for prevention and intervention of overweight problem.

Tracking overweight and obesity in Japanese children; a six years longitudinal study.

Childhood overweight/obesity is growing steeply, globally. It is usually regarded as a risk factor for severe obesity over life-time course. Here, we investigated temporal course of overweight/obesity development in Japanese school children. A six-year longitudinal study was performed on 16,245 Japanese primary school children (8,427 boys and 7,818 girls) comprising three cohorts of 1(st) approximately 3(rd) grade. A baseline survey was conducted at 2001, followed by annual baseline studies from 2002 approximately 2007 to determine the prevalence and track overweight/obesity. Our results showed that the prevalence of overweight was 15 approximately 23% in boys and 15 approximately 18% in girls, however, for obesity it ranged between 4 approximately 7% in boys; and 2 approximately 4% in girls. As regards for tracking status, 60 approximately 80% of overweight and 35 approximately 70% of obese Japanese primary school boys track into overweight or obese junior high school adolescents. However, these percentages are lower among primary school girls, where only 50 approximately 70% overweight and 30 approximately 60% obese primary school girls track into overweight and obese adolescents, respectively. We conclude that Japanese boys are fatter than girls; and approximately 80% of overweight/obese Japanese primary school children track into junior high school overweight/obese adolescents.

[An approach to prevent lifestyle-related diseases of children in collaboration with various organizations in Tokushima].

OBJECTIVE: To support the goal of "Lifetime health promotion from childhood", a Committee for Strategies to Prevent Lifestyle-related Diseases was established as part of the Tokushima Prefecture Medical Association in 2000. In this report, we present the activities of this committee, in collaboration with various organizations such as schools, a medical association, health administrators and universities. ACTIVITIES: In 2000, a physical survey was performed for all students in primary and junior high schools in Tokushima prefecture. Subsequently, a software program for determining the degree of obesity using the standard body weight of Tokushima children was produced. In 2001, the committee conducted a survey concerning measures taken against lifestyle-related diseases by each organization. In 2003, a "Health management system for obesity in children" and a "School urine examination system" were established to identify high-risk students who should be taken to consult primary physicians. These medical intervention systems have allowed continuous calculation of real numbers and actual status of problems with overweight and obese children. Moreover, we performed lifestyle habit surveys among about 3000 students and produced manuals for population-based approaches. RESULTS: Compared with nationwide values, there was no difference in height, but the weight and BMI (Body Mass Index) of Tokushima students were larger. The survey concerning measures against lifestyle-related diseases clarified the present status of school health committees, staffing available to provide individual/nutritional guidance and the execution rate of collaborative projects in each organization. The intervention systems for visits to primary physicians have continued to show almost constant consultation rates. Approximately 80% of severely obese children had at least one medical problem. The lifestyle habits survey did not identify any marked differences in children of Tokushima Prefecture compared with nationwide values, except for a slightly earlier waking-up time. However, this survey demonstrated differences in lifestyle habits according to the body physique, and a relationship between eating meals with the family and other lifestyle habits. The numbers of overweight and severely obese children in Tokushima have been decreasing since the peaks of 2001 and 2002. CONCLUSIONS: Activities to prevent lifestyle-related diseases from childhood have continued in collaboration with various organizations in Tokushima. The prefecture-wide physical surveys and high-risk intervention strategies might have had good social effects in Tokushima. As a result, the number of obese children may be decreasing.

Proteasome subunits mRNA expressions correlate with male BMI: implications for a role in obesity.

Obesity as well as its associated chronic diseases and adverse health consequences such as type 2 diabetes mellitus, dyslipidemia, hypertension, and coronary artery disease are afflicting middle-aged adults and an ever greater number of children globally. We planned to investigate new obesity-related factors using proteomics approaches in a randomly selected three high and three low BMI samples of Epstein-Barr-transformed B (EBV-B) lymphoblastoid cell lines prepared from two groups of young Japanese men with different BMI. To search novel obesity-related factors, comparisons of protein expressions between high and low BMI groups were carried out by two-dimensional gel electrophoresis (2-DE). Gene transcripts of proteasome subunits found out from 2-DE were further determined by quantitative real-time PCR. Results from proteomics approach showed that the expression of proteasome alpha subunit type 5 (PSMA5) was significantly lower in the high BMI male group than in those with low BMI (P < 0.05). To validate these results, we expanded the study to include 20 more men and used real-time PCR to quantify the mRNA expression level in their EBV-B cells. Both PSMA5 and PSMA2 of EBV-B cells showed negative correlation with BMI. Furthermore, the mRNA levels measured in the peripheral blood B lymphocytes for many proteasome subunits in 75 healthy men and women showed significant negative correlation with BMI in healthy men. Our findings suggest that proteasome expression may play a key role in obesity.

Proteasome subunits are regulated and expressed in comparable concentrations as a functional cluster.

The proteasome is the main proteolytic enzyme that functions in the ubiquitin-proteasome system. The 26S proteasome has multi-subunit protease complexes consisting of 20S subunits composed of four seven-numbered rings with two outer rings containing alpha subunits and two central rings composed of beta subunits, and 19S caps of 6 ATPase and 11 non-ATPase subunits; however, it is unclear how these subunits are regulated and the 26S proteasomes assembled. To verify whether each subunit's mRNA expression is associated with the mRNA expression of other proteasome subunits, we carried out expression analysis of 34 proteasome subunits mRNA on peripheral blood from 75 subjects. The expression of proteasome subunits mRNA was comparable in each individual of the studied population and the mRNA expression has been investigated in each 20S or 19S proteasome. Our results suggest that each type of subunit is regulated by respectively common factors, and that the 20S and 19S proteasomes are regulated by different systems.

Effects of lifestyle habits and eating meals together with the family on the prevalence of obesity among school children in Tokushima, Japan: a cross-sectional questionnaire-based survey.

Obesity in children has become a major global public health concern. The prevention of obesity must start from early childhood in order to establish sound lifestyle habits and promote healthy adulthood. In this study, we evaluated factors associated with the prevention of obesity and the development of healthy lifestyle habits in children. A cross-sectional, questionnaire-based survey was performed in elementary and junior high school students in Tokushima Prefecture, Japan, during the summer of 2004. The questionnaire consisted of 30 items such as physique, sleep, eating habits, diet, exercise, free time, and attending after-school lessons. Our study revealed that eating meals as a family every day is associated with a lower rate of obesity as well as getting good lifestyle habits such as eating balanced meals and getting enough sleep. Of the 3,291 students who responded to the questionnaire, 2,688 (81.7%) reported that they eat meals with their family every day. The percentage of students who eat meals with their family every day decreased with increasing school grade, with the lowest percent in the junior high school students. However, the results regarding female junior high school students revealed a marked association between eating meals with the family every day and good lifestyle habits. We recommend that parents and school teaching staff encourage the establishment of sound, healthy lifestyle habits in children from early childhood as an effective measure for the prevention of obesity.

Reduced carnitine level causes death from hypoglycemia: possible involvement of suppression of hypothalamic orexin expression during weaning period.

The mechanism of onset of hypoglycemia in patients with carnitine deficiency has yet to be determined. Using mice with systemic carnitine deficiency (JVS mice), we examined this mechanism, focusing on the weaning period (days 14-28 postpartum). For normal mice, the survival rate was 100%, and no hypoglycemia was observed at all. Gastric lactose began to decrease on day 17, and cellulose increased sharply in amount thereafter. For JVS mice, the survival rate was 77% on day 14 and 28% on day 28. From day 21 on, hypoglycemia was noted. Gastric lactose had disappeared almost completely by day 17, and cellulose was almost undetectable from days 14 to 28. Expression of orexin mRNA in the hypothalamus did not differ between JVS and normal mice on day 14, but was suppressed in JVS mice on days 21 and 28. When JVS mice were fed a carnitine-rich diet, suppression of expression of orexin mRNA in hypothalamus was eliminated, and on day 28 lactose and cellulose were detected in the stomach without hypoglycemia. In conclusion, the suppression of the expression of orexin in the hypothalamus during the weaning period may be involved in the marked anorexia in JVS mice, which eventually leads to death from hypoglycemia.

Prevalence of metabolic complications in children with severe obesity.

BACKGROUND: The purpose of the present paper was to clarify the prevalence of metabolic complications in severely obese children. METHODS: The subjects of the present study were 367 severely obese Japanese children in Tokushima, who were more than 150% of the standard weight for their sex and height (school grades 1-9; age range, 6-16 years). Data concerning anthropometric and metabolic parameters (body fat %, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, uric acid, blood glucose, serum insulin, alanine aminotransferase, and blood pressure) were analyzed. RESULTS: The prevalence of each abnormality in obese children was high compared with that in the general population. Metabolic variables were correlated with each other. A total of 80.4% of severely obese children had at least one complication. CONCLUSION: Severely obese children have various metabolic abnormalities even during their early school years. Intervention by primary physicians in cooperation with schools is needed for the prevention of lifestyle-related diseases.

Correlation of month and season of birth with height, weight and degree of obesity of rural Japanese children.

Month and season of birth are thought to influence height, weight and degree of obesity in schoolchildren. A cross-sectional study was designed to measure the height and weight of all children aged 6-15 years attending primary and junior high schools in Tokushima Prefecture, Japan. Data were standardized (z-scores) and analysed separately by gender and age. The mean z-score for height and weight were the highest in subjects born during the months of spring and the lowest in those born during the months of winter (p < 0.0001), whereas the means were significantly higher in children born during the months of summer than in those born during the months of autumn (p < 0.0001). A gradually decreasing trend of height and weight was observed in children of both genders born between May and Mar (from spring to winter). There was no significant difference in degree of obesity among the four seasons of birth for boys and girls. The highest prevalence of obese boys have born during spring (among 6-year-old boys) and summer (among 7-year-old boys), whereas the highest prevalence of obese girls have born during spring (among 6-year-old girls) and winter (among 10-year-old girls). Our findings suggest that month and season of birth influence height and weight of schoolchildren in Tokushima but not their degree of obesity.

A/G heterozygote of the A-3826G polymorphism in the UCP-1 gene has higher BMI than A/A and G/G homozygote in young Japanese males.

UCP-1 is suggested to have important roles for thermogenesis and energy expenditure. To elucidate whether the A-3826G polymorphism that is located in the 5' flanking region of the UCP-1 gene has roles in healthy young people, the polymorphism was genotyped among 251 young Japanese men whose mean age is 22.7 years old. We analyzed relationship between the A-3826G polymorphism and body mass index (BMI) or six biochemical parameters, serum concentration of total cholesterol (TC), high density lipoprotein (HDL) cholesterol, triglyceride (TG), asparatate aminotransferase (AST), alanine aminotransferase (ALT), fasting plasma glucose. The genotype frequencies were observed at the frequencies of 24.3% for AA, 48.2% for AG and 27.5% for GG, respectively. When BMI and the biochemical parameters were compared by ANOVA among individuals with each genotype, the statistical difference was observed only for BMI (P=0.016). Bonferroni's test demonstrated that the men with the AG genotype have higher BMI than those with the AA genotype (22.4+/-2.8 vs. 21.4+/-2.2) (P=0.04). The individuals with the AG genotype also showed trend to have higher BMI than those with the GG, although the difference was not statistically apparent (22.4+/-2.8 vs. 21.5+/-2.3) (P=0.07). Our results indicated that the young healthy Japanese men with the AG heterozygote showed higher BMI than those with other genotypes.

Association of estrogen receptor alpha gene polymorphisms and lifestyle factors with calcaneal quantitative ultrasound and osteoporosis in postmenopausal Vietnamese women.

Genetic and lifestyle factors are important in the pathogenesis of osteoporosis. We investigated the relationships of PvuII and XbaI polymorphisms of the estrogen receptor alpha (ER-alpha) gene, lifestyle factors with speed of sound at the calcaneus (calcaneal SOS) and osteoporosis in a population-based study of 140 healthy postmenopausal women. By an analysis of covariates, women with higher copies of P or X alleles had higher calcaneal SOS compared with others (P=0.012, PP vs. pp; P=0.045, Xx vs. xx). Women with lower copies of px or higher copies of PX haplotypes had higher calcaneal SOS compared with others (P=0.021, 0 px vs. 2 px; P=0.011, 1 PX vs. 0 PX). The px and PX haplotypes, age and years since menopause were found to be independent predictors of calcaneal SOS in multiple linear regression models. Using logistic regression, we found an increased osteoporosis risk with evidence for a px haplotype dose effect (OR=2.82, 95% CI=1.50-5.31, P=0.001) and for a PX haplotype dose effect (OR=0.42, 95% CI=0.19-0.93, P=0.033). An increased educational level was associated with a reduced risk of osteoporosis (P=0.035 in the model with px, P=0.044 in the model with PX). In conclusion, the present study suggests that PvuII and XbaI polymorphims of the ER-alpha gene, age, years since menopause and educational level are associated with bone density, as assessed by calcaneal SOS, and osteoporosis in postmenopausal Vietnamese women.