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Introduction: Health benefits of physical activity (PA) may be mediated by DNA methylation alterations. The purpose of the current study was to comprehensively identify CpG sites whose methylation levels were associated with accelerometer-assessed total PA in a general Japanese population. Methods: The study participants were from the baseline survey of Saga Japan Multi-institutional Collaborative Cohort. PA was objectively measured by a single-axis accelerometer for 7 d. We used a two-stage strategy. In the discovery stage, we performed a meta-analysis of two epigenome-wide association studies of total PA in 898 individuals (a combination of random sample (n = 507) and case–control study sample (n = 391)). Peripheral blood DNA methylation levels were measured using Infinium EPIC or HM450 arrays. In the replication stage, we subsequently examined whether CpG sites significantly associated (P < 1 × 10−5) with total PA were replicated in another sample (n = 1711), in which methylation levels were measured by pyrosequencing. A multiple linear regression was performed to determine the cross-sectional association between total PA and methylation levels with adjustment for potential confounders, including body mass index. A fixed-effects model was used in the meta-analysis. Correlations between total PA–associated DNA methylation and several inflammatory markers, such as high-sensitivity C-reactive protein, were also conducted. Results: In the meta-analysis, nine CpG sites were significantly associated with total PA (P < 1 × 10−5). Among the nine sites, one site cg07030336 (annotated to VTI1A/ZDHHC6 gene) was successfully replicated (P = 0.009). Conclusions: The current study showed that greater accelerometer-assessed total PA was associated with higher DNA methylation levels at cg07030336 (VTI1A/ZDHHC6) in the general population. In addition, we found a divergent relationship between the methylation levels at cg07030336 and several inflammatory biomarkers. [ABSTRACT FROM AUTHOR]

Background: Accumulated evidence suggests a weak positive relationship between psychosocial stress and body mass index (BMI), but little is known about stress coping strategies and BMI. Objective: We aimed to examine if perceived stress and coping strategies are related to BMI, with any of their mutual interactions on BMI. Methods: This cross-sectional study included 5,063 men and 6,982 women aged 40-69 years. A self-administered questionnaire ascertained perceived stress and 5 items of coping strategies (emotion expression, emotional support seeking, positive reappraisal, problem solving, and disengagement). Analyses were performed by gender with adjustment for age, socioeconomic status, and lifestyle factors. Results: No significant associations were detected between perceived stress and BMI in either men (Ptrend = 0.09) or women (Ptrend = 0.58). In men, however, ‘disengagement’ showed an inverse association with BMI (Ptrend < 0.001), and ‘positive reappraisal’ and ‘problem solving’ revealed a positive association with BMI (Ptrend = 0.04 and 0.007, respectively) even after controlling for perceived stress. A possible interaction between perceived stress and ‘disengagement’ on BMI was found in men (Pinteraction = 0.027); the inverse association between ‘disengagement’ and BMI was more evident in higher levels of stress (β = −0.13, Ptrend = 0.21 in low; β = −0.22, Ptrend = 0.01 in medium; and β = −0.24, Ptrend = 0.06 in high). In men, ‘disengagement’ was inversely associated with overweight/obesity (odds ratio 0.79, 95% confidential interval 0.67-0.95), and “positive reappraisal” was positively associated with it (1.25, 1.02-1.54). Conclusions: Coping strategies may have an important role in developing overweight/obesity, particularly in men. [ABSTRACT FROM AUTHOR]

Background Secreted protein acidic and rich in cysteine (SPARC) may play a role in the prevention of colon cancer through exercise, while SPARC is considered as a promoter of insulin resistance. The purpose of the present study was to clarify the effects of replacing sedentary time with either light-intensity PA (LPA) or moderate- to vigorous-intensity PA (MVPA) on serum SPARC in a general population. Methods The study subjects were 4000 men and 6040 women (40 to 69 years) who participated in baseline surveys of a population-based cohort study. Sedentary time, LPA, and MVPA were objectively measured by an accelerometer. The serum SPARC concentration was measured by an enzyme-linked immunosorbent assay. Using an isotemporal substitution model, cross-sectional associations of replacing sedentary time with either LPA or MVPA on serum SPARC levels were analyzed according to sex. Adjustment was made for potential confounding factors. Results In men, replacing 60 min of sedentary time with 60 min of MVPA was associated with 23 ng/mL (confidence interval -43, -2) lower serum SPARC levels even after adjusting for confounders, including the BMI (P = 0.028), while no such association was observed for LPA. Furthermore, no such significant replacement effects were observed in women. Conclusions The current study showed that replacing sedentary time with MVPA results in reduced serum SPARC concentrations in men. Key messages Effect of habitual PA to decrease circulating SPARC is PA intensity-specific. [ABSTRACT FROM AUTHOR]