Three unique papers from different areas are highlighted in this month's journal. First, in a study in the basic science area, Butts et al. examined the effects of exercise on changes in the DNA methylation of ASC, a protein involved in inflammatory activation, in persons with heart failure. They found that heart failure patients who completed a 3-month walking aerobic exercise intervention had higher levels of DNA methylation of the inflammasome adaptor protein, ASC, lower ASC mRNA expression, and lower levels of its product of activation, interleukin-1 β, with medium to large effect sizes. This study provides some insight into how we can link our current understanding of the role of exercise on immune responses and potential underlying mechanisms that may ultimately lead to non-pharmacological intervention methods of reducing inflammation in persons with heart failure.
In a different direction, Raine et al. examined the relationship between adiposity, particularly adipose tissue found in the visceral cavity (VAT), and cognitive function and academic achievement among children. Fifty-five obese children and 55 normal weight children completed cognitive and academic tests. The results revealed that, relative to their normal weight counterparts, obese children had significantly lower performance on academic tests of reading and math. Furthermore, among children with obesity, higher VAT was associated with poorer intellectual abilities and cognitive performance. Overall, these results suggest that obese children perform worse on academic achievement tests than their normal weight peers, and that among children with obesity, cognition is negatively related to VAT. Thus, maintaining a normal body weight and limiting adipose tissue in the visceral cavity may be beneficial for academic success and cognition.
Finally, workers in many industries often perform consecutive days of prolonged, strenuous work in the heat. These conditions cause considerable heat strain over an entire work day as well as next-day effects (fatigue, fluid depletion, etc.), which exacerbate heat strain relative to the previous work day, especially in middle-age adults (>50 yr). In this context, Notley et al. demonstrated that, when evaluated in middle-age (~60 yr) men on the day following a prolonged, simulated work day in the heat (~10 h), those next-day increases in heat strain could be ascribed to impairments in whole-body heat loss that worsen body heat storage, particularly during moderate-to-high intensity work. Given the rising number of older adults employed in arduous occupations, these important outcomes indicate that refinement to current workplace heat exposure guidelines may be required to protect older workers from heat-related injury over consecutive shifts.
L. Bruce Gladden
School of Kinesiology