Negative perception of socioeconomic status with depressive mood down-regulates expression of <i>PPBP</i> and <i>SLC1A7</i> genes in peripheral blood leukocytes

<p>Inequality in socioeconomic status (SES) is associated with an increased risk for the development of mental health problems. Here, we examined the association between socioeconomic status (SSS) and psychological distress, and measured gene expression signatures in peripheral blood leukocytes responsible for this association, in 129 healthy adults (27 males and 102 females, aged 44.0 ± 13.0 years) working in a private hospital in Japan. Depressive mood was assessed by Zung Self-rating Depression Scale (SDS). A multiple regression analysis adjusted for gender and age showed that subjective SSS was independently and negatively associated with SDS score. We next focused on 9 subjects who exhibited low SSS scores and 11 subjects with high SSS scores. Microarray analysis revealed that levels of 522 mRNAs were differentially expressed in periheral leukocytes between low and high-SSS groups. The differentially expressed genes were preferentially involved in cellular movement or inflammatory responses. Among them, mRNA levels of <i>pro</i>-<i>platelet basic protein</i> (<i>PPBP</i>) and <i>solute carrier family 1</i> (<i>glutamine transporter</i>), <i>member 7</i> (<i>SLC1A7</i>) were negatively correlated with SSS scores. Our results re-confirmed the association between negative perception of SES and depressive mood in healthy adults, and suggest a possible involvement of <i>PPBP</i> and <i>SLC1A7</i> in the association.</p

Flow chart diagram showing the genome-wide DNA methylation analysis.

<p>DMPs, differentially methylated CpG positions; <i>Ratio1</i>, the ratio of the β-value after training to that before training.</p

Effects of milk product intake on thigh muscle strength and <i>NFKB</i> gene methylation during home-based interval walking training in older women: A randomized, controlled pilot study

<div><p>Background</p><p>Muscle atrophy with aging is closely associated with chronic systemic inflammation and lifestyle-related diseases. In the present study, we assessed whether post-exercise milk product intake during 5-month interval walking training (IWT) enhanced the increase in thigh muscle strength and ameliorated susceptibility to inflammation in older women.</p><p>Methods</p><p>Subjects [n = 37, 66±5 (standard deviation) yrs] who had been performing IWT for >6 months participated in this study. They were randomly divided into the following 3 groups: IWT alone (CNT, n = 12), IWT + low-dose post-exercise milk product intake (LD, n = 12; 4 g protein and 3 g carbohydrate) or IWT + a 3-times higher dose of milk product intake than the LD group (HD, n = 13). They were instructed to repeat ≥5 sets of fast and slow walking for 3 min each at ≥70% and 40% peak aerobic capacity for walking, respectively, per day for ≥4 days/week.</p><p>Results</p><p>After IWT, thigh muscle strength increased in the HD group (8±2%) more than in the CNT group (-2±3%, <i>P</i> = 0.022), despite similar IWT achievements between the groups (<i>P</i>>0.15). Pyrosequencing analysis using whole blood showed that methylation of <i>NFKB1</i> and <i>NFKB2</i>, master genes of inflammation, was enhanced in the HD group (29±7% and 44±11%, respectively) more than in the CNT group (-20±6% and -10±6%, respectively; <i>P</i><0.001). Moreover, the genome-wide DNA methylation analysis showed that several inflammation-related genes were hyper-methylated in the HD group compared with that in the CNT group, suggesting greater pro-inflammatory cytokine gene suppression in the HD group.</p><p>Conclusion</p><p>HD milk product intake after exercise produced a greater percent increase in thigh muscle strength and <i>NFKB1</i> and <i>NFKB2</i> gene methylation during IWT in physically active older women.</p><p>Trial registration</p><p>UMIN-CTR No. <a href="https://clinicaltrials.gov/ct2/show/UMIN000024544" target="_blank">UMIN000024544</a> and No. <a href="https://clinicaltrials.gov/ct2/show/UMIN000024912" target="_blank">UMIN000024912</a></p></div

Effects of milk product intake on thigh muscle strength and <i>NFKB</i> gene methylation during home-based interval walking training in older women: A randomized, controlled pilot study - Fig 2

<p><b>Percent changes after training in muscle strength (A) and methylation of the <i>NFKB1</i> and <i>NFKB2</i> promoter regions assessed by pyrosequencing (B)</b>. The data were adjusted for pretraining values by ANCOVA. The mean and SE bars are presented for 12, 12, and 13 subjects in the IWT control (CNT), IWT + low-dose (LD) and IWT + high-dose milk product intake (HD) groups, respectively. **Significant differences from pretraining values, <i>P</i><0.01. Significant differences from the CNT group, †<i>P</i><0.05 and †††<i>P</i><0.001. Significant differences from the LD group, ‡<i>P</i><0.05 and ‡‡<i>P</i><0.01. <b>A</b>: Average percent changes in isometric knee extension (ΔF_EXT) and flexion (ΔF_FLX) forces are presented. <b>B</b>: Average percent changes in CpG sites 1–7 for <i>NFKB1</i> (<i>upper</i>) and average percent changes in CpG sites 1–6 for <i>NFKB2</i> (<i>lower</i>) are presented.</p

Physical characteristics and fitness at baseline and changes after training.

<p>Physical characteristics and fitness at baseline and changes after training.</p

Primers used for the pyrosequencing assay.

<p>Primers used for the pyrosequencing assay.</p

Methylation of the <i>NFKB1</i> and <i>NFKB2</i> promoter regions at baseline and changes after training assessed by pyrosequencing.

<p>Methylation of the <i>NFKB1</i> and <i>NFKB2</i> promoter regions at baseline and changes after training assessed by pyrosequencing.</p

CONSORT flow diagram.

<p>IWT, interval walking training.</p

Dietary intake per day during the training period.

<p>Dietary intake per day during the training period.</p

qPCR validation of time-dependent changes in seven miRNA levels.

<p>Time-dependent changes in miR-16 (A), miR-20b (B), miR-26 (C), miR-126 (D), miR-144 (E), miR-144* (F), and miR-29a (G) levels were measured by qPCR using <i>RNU48</i> as endogenous quantity control. Values are mean ± SEM (<i>n</i> = 25). *In the graphs, significantly different by repeated measured ANOVA and Bonferroni post hoc test (<i>p</i><0.05).</p