Physical activity modifies the FTO effect on body mass index change in Japanese adolescents.

BACKGROUND: Evidence of the effects of fat mass and obesity-associated (FTO) variation and long-term effects of physical activity (PA) on adiposity in adolescents is largely scarce. This study therefore investigated whether PA modulates the effects of the FTO on body mass index (BMI) changes in Japanese adolescents between the ages of 13 and 18 years. METHODS: Data on 343 subjects (156 boys; 187 girls) who were enrolled in 2006 and 2007 at schools in Shunan City, Japan, were collected. Genotyping (rs1558902) was conducted, and anthropometry and blood test results were recorded for subjects in the eighth grade. A second survey involving self-reporting of anthropometry was conducted when the subjects were in the 12th grade. PA was estimated using the International Physical Activity Questionnaire. BMI and the standard deviation score for BMI (BMI-SDS) were calculated. BMI changes and BMI-SDS changes were compared between FTO genotypes using a multivariate model. RESULTS: The effect of the interaction between PA and the FTO genotype on BMI changes was significant in boys but not in girls. In boys, PA had a significant negative influence on BMI-SDS changes in those with the AA genotype and a significant positive influence on BMI and BMI-SDS changes in those with the TT genotype. CONCLUSION: The influence of PA on BMI change and BMI-SDS change varies on the basis of genotype. PA modified the effect of FTO on BMI change in Japanese boys.

Survey on awareness of folic acid recognition and intake by female students.

To reduce the risk of neural tube defects, studies have been conducted on female students of medical services, nutritional science, and nursery education that investigated the awareness of folic acid by using questionnaires. Many investigators have suggested the need to provide detailed information about the awareness of folic acid and knowledge about folic acid intake and neural tube defect risk reduction. The dietary habits of female students showed a positive correlation with their estimated folic acid intake, suggesting that improvements in dietary habits are associated with the consumption of folic acid. The importance of folic acid intake must be more aggressively promoted among female students. Thus, many learning opportunities should be provided for such students to help increase their folic acid intake.

Twenty-four-hour urinary sodium and potassium excretion and associated factors in Japanese secondary school students.

Data on the sodium and potassium intake using dietary records among schoolchildren are sorely lacking in the Japanese literature. Some evidence indicates that sodium and potassium intake has been correctly measured, but information concerning these associated factors is scarce. The 24-h urine samples and first morning voiding (overnight) samples were collected twice from 68 secondary schoolchildren in Suo-Oshima Town, Japan. Sodium, potassium and creatinine concentrations were analyzed. Body height and weight were measured, and menstruation and physical activity were assessed via questionnaires. We analyzed the 24-h samples with a >20-h collecting period and no missed voiding. The 24-h sodium excretion was 163.2±36.8 and 149.8±45.1 mmol per 24 h for the boys and girls, respectively. Considering daily habits and loss from sweat, intake was assumed to be 10.6±1.2 and 10.0±2.4 g per day for the boys and girls, respectively. The 24-h potassium excretion was 43.4±10.8 and 45.8±14.4 mmol per 24 h for the boys and girls, respectively. Estimated usual potassium intake was 2195±401 and 2330±630 mg per day for the boys and girls, respectively. Sodium excretion was associated with sodium and potassium concentrations in overnight urine samples and physical activity. Potassium excretion was associated with height and physical activity. We described daily sodium and potassium excretion in Japanese secondary schoolchildren. Excretion was associated more with physical activity than with bodyweight. Therefore, the estimation methods used in adults are not applicable for use in adolescents.

Dietary Fiber Consumption Decreases the Risks of Overweight and Hypercholesterolemia in Japanese Children.

AIMS: It remains inconclusive whether high dietary fiber intake decreases the risk of obesity, hypercholesterolemia or high blood pressure during childhood. Therefore, this study investigated the relationships of dietary fiber intake with weight status and related clinical parameters among Japanese children. METHODS: We analyzed the data of 5,600 subjects aged 10-11 years, between 2006 and 2010. Fiber intake was assessed using the Brief-type Diet History Questionnaire. Body height and weight and blood pressure were measured. Serum levels of total cholesterol, low- and high-density lipoprotein cholesterol and triglycerides were analyzed. Fiber intake was categorized into quintiles, and multivariate models were used to adjust for lifestyle factors. RESULTS: Total fiber intake decreased the risks of overweight and high total cholesterol (OR Quintile 5 vs. Quintile 1 overweight: 0.71 for boys, 0.40 for girls; total cholesterol: 0.60 for boys, 0.66 for girls). Water-soluble fiber intake was associated with a lower risk of high blood pressure, although the ORs were not significant. CONCLUSIONS: Increasing the dietary fiber intake in Japanese children may have favorable effects on overweight and hypercholesterolemia.

Fat-mass and obesity-associated gene variant and changes of body mass index from ages 3 to 13 years.

OBJECTIVE: The effect of the fat-mass and obesity-associated (FTO) gene minor allele on the change of adiposity from childhood to adolescence among Asians remains unclear, and is expected to differ among the developmental stages from childhood to adolescence. We assessed the relationship between a FTO variant and changes in body mass index (BMI) between 3 and 13 years of age among Japanese. METHODS: Subjects were 66 fifth graders (37 boys, 29 girls) enrolled in 2006 from Shunan City, Japan, and genotyped (rs1558902). Anthropometrics were measured at fifth grade and three years later at eighth grade, and data for these individuals recorded at 3 years of age by the health center were included. The effects on BMI and the BMI-standard deviation score (SDS) were analyzed after adjusting for age and sex. RESULTS: The minor allele of FTO was positively associated with BMI and BMI-SDS among boys at an age of 10 years (ß=1.779 and 0.812, respectively). The risk allele was positively associated with changes in BMI among boys between 3 and 10 years of age (ß=1.656). However, negative associations with changes in BMI and BMI-SDS were found among boys between 10 and 13 years of age (ß=-0.875 and -0.512, respectively). CONCLUSION: The increment of adiposity at 10 years of age in boys might be influenced by the FTO variant, but this influence was significantly reduced at 13 years.

C677T mutation in methylenetetrahydrofolate reductase gene and neural tube defects: should Japanese women undergo gene screening before pregnancy?

We analyzed the role of maternal C677T mutation in methylenetetrahydrofolate reductase (MTHFR) gene on spina bifida development in newborns. A total of 115 mothers who had given birth to a spina bifida child (SB mothers) gave 10 mL of blood together with written informed consent. The genotype distribution of C677T mutation was assessed and compared with that of the 4517 control individuals. The prevalence of the homozygous genotype (TT) among SB mothers was not significantly different from that among the controls (odds ratio [OR] = 0.65; 95% confidence interval [CI] = 0.31-1.25; P = 0.182), suggesting that MTHFR 677TT genotype in Japan is not associated with spina bifida development in newborns. The T allele frequency was not increased in SB mothers (34.8%) as compared to that of the control individuals (38.2%). Further, the internationally reported association between the two groups was found to be similar in all 15 countries studied except the Netherlands, where the TT genotype was found to be a genetic risk factor for spina bifida. For the prevention of affected pregnancy every woman planning to conceive has to take folic acid supplements 400 µg a day and the government is asked to take action in implementing food fortification with folic acid in the near future. In conclusion, it is not necessary for Japanese women to undergo genetic screening C677T mutation of the MTHFR gene as a predictive marker for spina bifida prior to pregnancy, because the TT genotype is not a risk factor for having an affected infant.

[Changes in life styles of pregnant women and risks for having a pregnancy afflicted with spina bifida].

AIMS: Though periconceptional intakes of folic acid could prevent the occurrence of spina bifida by 50 to 70%, the prevalence has not shown any decreasing tendency during the past 30 years in Japan. We aim to analyze various parameters through life style questionnaires and 3-day food records obtained from pregnant women the last 10 years, and to examine whether their life styles have been shifting to the direction of lowering the incidence of spina bifida. MATERIALS AND METHODS: Life style questionnaires inquired of knowledge of folic acid in relation to preventing spina bifida during a pregnancy and other relevant parameters, which were collected from 11,861 participants during a period of from 2002 to 2011. Food records asked participants to semi-quantitatively describe diets and beverages they consumed for a 3-day period, which were collected from 1,081 pregnant women from 2003 to 2011. RESULTS: Life style questionnaires demonstrated that knowledge of folic acid and the proportion of those who took folic acid supplements elevated from 15.3 and 9.1% in 2002 to 43.7 and 61.5% in 2011, respectively, that comparison of those who took folic acid supplements from 2008 to 2011 residing in one of 8 districts of Japan showed a significant difference, i.e., the proportion of those in the Chugoku or Kyushu district being significantly lower compared to that in the Hokkaido district, and that other life style parameters have not much altered the past 9 years, e.g., those who conceived as planed being 67%, those who confirmed own pregnancy within 6 weeks of pregnancy being 70%, those who took balanced diets being 65%, and those who did not smoke or drink being 95% and 96%, respectively. Three-day food records revealed that the mean dietary folate intakes ranged from 260 to 360 microg/day in each year which were less than the recommended dietary allowance (RDA) publicized by the government, but that the proportion of pregnant women in the first trimester who consumed folic acid supplements from 4 weeks prior to to 12 weeks after conception increased from 7.4% in 2003 to 69.6% in 2011. CONCLUSIONS: As a whole it could be stated that life styles of pregnant women have been shifting toward the direction the past 10 years where the risk for having a pregnancy afflicted with spina bifida is to be decreased. Medical doctors, nurses, midwives, dietitians and pharmacists are asked to repeatedly supply important information on folic acid and to advise taking folic acid supplements 400 microg a day to women planning to conceive or women in the reproductive age.

The effects of fat mass and obesity-associated gene variants on the body mass index among ethnic groups and in children and adults.

Genome-wide association analyses have revealed common gene variations related to obesity. Variants of the fat mass and obesity-associated (FTO) gene among more than 40 genes studied were most closely associated with obesity, but the association varies among ethnicities. Moreover, the effect is significant in people of European descent as well as Asians, but less significant among people of African descent. Although the variants were also associated with type 2 diabetes and glucose homeostasis, the associations were attenuated or abolished after adjusting for adiposity. The present review considers our current understanding of the effects of the FTO variants in different ethnic groups and in adults and children.

High-protein diet suppresses corpus atrophic gastritis in Helicobacter pylori infected Mongolian gerbils.

To investigate the effect of a high-protein diet on corpus atrophic gastritis in Helicobacter pylori-infected Mongolian gerbils, H. pylori was administered orally to 5-wk-old Mongolian gerbils; and the animals were then fed a control diet (Group C); a high-fat diet (Group F: 40% fat); a high-protein diet (Group P: 32% protein); or a high-fat, high-protein diet (Group FP: 40% fat, 32% protein) for 50 wk beginning at 7 wk of age. In uninfected animals, the mucosal thickness of the corpus was significantly greater in Group P and Group FP than in Group C (P < 0.05). In infected animals, the serum gastrin level was significantly decreased in Group FP and marginally significantly decreased in Group P (P = 0.057) in comparison to Group C. The mucosal thickness of the corpus was significantly greater in Group P and Group FP than in Group C (P < 0.05). Mean inflammation and atrophy scores in the corpus were significantly lower in the high-protein groups (Groups P and FP) than in the control groups (Groups C and F; both inflammation and atrophy: P < 0.05). In conclusion, long-term administration of a high-protein diet suppresses corpus atrophic gastritis in H. pylori-infected Mongolian gerbils.

Action of microparticles of heparin and alginate crosslinked gel when used as injectable artificial matrices to stabilize basic fibroblast growth factor and induce angiogenesis by controlling its release.

Alginate is an acidic polysaccharide like the glycosaminoglycans and is a candidate for use as an artificial matrix. We developed a novel alginate gel sheet that is crosslinked with heparin (H/A gel sheet) and discovered its properties of releasing biologically active basic fibroblast growth factor (bFGF), a representative member of the heparin-binding growth factors (HBGFs), for about 1 month in vitro and of inducing angiogenesis in vivo. In the present study, the H/A gel sheet was mechanically broken up to produce easily injectable 50- to 200 microm microparticles of the gel (H/A gel particles), the properties of which were analyzed. The H/A gel particles cumulatively released 2.8 times as much bFGF as the H/A gel sheet, despite both having the same amount of bFGF adsorbed onto their gels. In addition, the bFGF-adsorbed H/A gel particles released a significant amount of bFGF, which stimulated cellular growth in a culture of human umbilical venous endothelial cells for up to 5 weeks. The subcutaneous injection of the bFGF-adsorbed H/A gel particles induced the formation of numerous microvessels in the tissue surrounding the gel. These results indicate that the H/A gel particles not only stabilize bFGF by preventing the occurrence of proteolysis or denaturation but also modulate its release from the gel. Because the H/A gel particles can be easily injected into the target tissues, this artificial matrix may be useful for the local delivery of HBGFs in the treatment of ischemic arterial diseases, as well as for regenerating or constructing tissues.