Association of FTO genotype with obesity and bone health among communitydwelling adults ; Goto Island study on bone health

Bone mass is tuned by various factors, including aging, menopause, low body weight, and genetic variations. Here, we showed an independent association between a genotype on the fat mass- and obesity-associated FTO gene (#610966 on OMIM) and bone loss after adjusting for age and body mass index (BMI). A cross-sectional study was nested in a prospective observational study of 1,828 participants (median age: 69 [62-76] years in men and 68 [61-75] years in women) residing in a rural city in western Japan (Goto Island study). Participants were recruited during medical checkups in 2014 and 2016 from the community-dwelling population. The bone mass of the calcaneus was evaluated using quantitative ultrasound. The single nucleotide polymorphism (SNP) rs1421085 was genotyped using a hydrolysis probe. The chi-squared test was used to determine whether the variants were in equilibrium in this population. There were differences in medians of BMI among the genotypes (24.3 in CC, 23.0 in CT, and 22.6 in TT, P = 0.01), but not in those of bone mass. There was a significant association between the minor allele (C) and being overweight in a gene dosage-dependent manner (BMI > 25, OR per allele =1.52, 95% CI = 1.07-2.14, P = 0.02 in men, OR = 1.48, 95% CI = 1.16-1.95, P = 0.01 in women). Logistic regression analysis showed a significant protective association in male carriers of the minor allele against low bone mass (QUS T-score less than -2.0) after adjusting for age and BMI in men aged 65-75 years (OR = 0.50, 95% CI = 0.27-0.96, P = 0.036), with no significant association in women.Our study indicated an association between the genetic polymorphism of FTO and bone mass among community-dwelling men aged 65-75 years. The polymorphism may play a role in bone health with higher BMI and other beneficial functions

Seasonal variation of non-shivering thermogenesis (NST) during mild cold exposure

Background: The physiological function of non-shivering thermogenesis (NST) has been investigated in recent years, and some studies have discussed the importance of NST with respect to human cold adaptation. The present study aimed to clarify individual and seasonal variations in NST that occurred as a result of mild cold exposure.Methods: Seventeen male university students participated in the present study during summer and winter. The climate chamber used was programmed so that ambient temperature dropped from 28°C to 16°C over an 80-min period. Physiological parameters of test subjects were recorded during the experiments.Results: Increases in oxygen intake (VO2) during cold exposure were significantly greater without shivering in winter than they were in summer. Respiratory exchange ratio (RER) was significantly lower during thermoneutral baseline and cold exposure in winter than it was during the same periods in summer. In addition, there was a significant negative correlation between ΔVO2 and ΔRER.Conclusions: Increase of VO2 without shivering indicated increase of NST, and decrease of RER depends on the metabolization of fat in winter. These results suggested that NST activity was activated by seasonal acclimatization, and individual variation of NST depends on individual variation of fat metabolism

Gender difference in N170 elicited under oddball task

Background: Some studies have reported gender differences in N170, a face-selective event-related potential (ERP) component. This study investigated gender differences in N170 elicited under oddball paradigm in order to clarify the effect of task demand on gender differences in early facial processing. Findings: Twelve males and 10 females discriminated targets (emotional faces) from non-targets (emotionally neutral faces) under an oddball paradigm, pressing a button as quickly as possible in response to the target. Clear N170 was elicited in response to target and non-target stimuli in both males and females. However, females showed more negative amplitude of N170 in response to target compared with non-target, while males did not show different N170 responses between target and non-target. Conclusions: The present results suggest that females have a characteristic of allocating attention at an early stage when responding to faces actively (target) compared to viewing faces passively (non-target). This supports previous findings suggesting that task demand is an important factor in gender differences in N170

Association of EGLN1 genetic polymorphisms with SpO2 responses to acute hypobaric hypoxia in a Japanese cohort

BACKGROUND: Recent studies have explored various genetic and physiological factors related to high-altitude adaptation in highlander populations. However, the effects of single nucleotide polymorphisms (SNPs), influencing such adaptation, on physiological responses to hypobaric hypoxia have not been examined in lowlanders with lowlander ancestry. Thus, we aimed to investigate the association between SNPs around the EGLN1 genomic region, possibly involved in high-altitude adaptation, and physiological changes to hypobaric hypoxia exposure in a cohort of Japanese lowlanders.METHODS: Physiological data were obtained from 46 healthy Japanese male students under different atmospheric pressure conditions (equivalent to sea level and altitudes of 2500 and 4000 m). Genotypes of seven SNPs around EGLN1 were determined in all subjects by PCR-direct sequencing or TaqMan SNP genotyping assay.RESULTS: Results of the association study suggest that percutaneous arterial oxygen saturation (SpO2) responses of individuals with rs12097901 and rs2790859 alleles, whose frequencies are high in highlander populations (HL alleles), may be susceptible to acute hypobaric hypoxia. SpO2 levels of individuals with HL alleles were lower than those of individuals with non-HL alleles. At the same time, the subjects with HL alleles did not appear to have any remarkable hematological or pulmonary features that may counteract the low levels of SpO2. One may hypothesize that the low SpO2 levels in HL allele carriers could be a risk factor for acute mountain sickness in Japanese population.CONCLUSIONS: Our findings suggest that rs12097901 and rs2790859 genotypes affect SpO2 responses and may be associated with the susceptibility to acute hypobaric hypoxia in Japanese population

Additional file 3: of Association of EGLN1 genetic polymorphisms with SpO2 responses to acute hypobaric hypoxia in a Japanese cohort

Figure S2. Relationship between BMI and SpO2 at sea level in 46 Japanese male students. (PDF 101 kb

Additional file 4: of Association of EGLN1 genetic polymorphisms with SpO2 responses to acute hypobaric hypoxia in a Japanese cohort

Table S2. Haplotype and diplotype frequencies of five SNPs around EGLN1 in 46 Japanese subjects. (PDF 71 kb