Impact of Acute Aerobic Exercise on Genome-Wide DNA-Methylation in Natural Killer Cells-A Pilot Study.

Natural Killer (NK-) cells reveal a keen reaction to acute bouts of exercise, including changes of epigenetic modifications. So far, exercise-induced alterations in NK-cell DNA-methylation were shown for single genes only. Studies analyzing genome-wide DNA-methylation have used conglomerates like peripheral blood mononuclear cells (PBMCs) rather than specific subsets of immune cells. Therefore, the aim of this pilot-study was to generate first insights into the influence of a single bout of exercise on genome-wide DNA-methylation in isolated NK-cells to open the field for such analyses. Five healthy women performed an incremental step test and blood samples were taken before and after exercise. DNA was isolated from magnet bead sorted NK-cells and further analyzed for global DNA-methylation using the Infinium MethylationEPIC BeadChip. DNA-methylation was changed at 33 targets after acute exercise. These targets were annotated to 25 genes. Of the targets, 19 showed decreased and 14 increased methylation. The 25 genes with altered DNA-methylation have different roles in cell regulation and differ in their molecular functions. These data give new insights in the exercise induced regulation of NK-cells. By using isolated NK-cells, exercise induced differences in DNA-methylation could be shown. Whether or not these changes lead to functional adaptions needs to be elucidated.

Acute Exercise Increases the Expression of KIR2DS4 by Promoter Demethylation in NK Cells.

Positive effects of exercise on cancer prevention and progression have been proposed to be mediated by stimulating natural killer (NK) cells. Because NK cell receptors are regulated by epigenetic modifications, we investigated whether acute aerobic exercise and training change promoter DNA methylation and gene expression of the activating KIR2DS4 and the inhibiting KIR3DL1 gene. Sixteen healthy women (50-60 years) performed a graded exercise test (GXT) and were randomized into either a passive control group or an intervention group performing a four-week endurance exercise intervention. Blood samples (pre-, post-GXT and post-training) were used for isolation of DNA/RNA of NK cells to assess DNA promoter methylation by targeted deep-amplicon sequencing and gene expression by qRT-PCR. Potential changes in NK cell subsets were determined by flow cytometry. Acute and chronic exercise did not provoke significant alterations of NK cell proportions. Promoter methylation decreased and gene expression increased for KIR2DS4 after acute exercise. A high gene expression correlated with a low methylation of CpGs that were altered by acute exercise. Chronic exercise resulted in a minor decrease of DNA methylation and did not alter gene expression. Acute exercise provokes epigenetic modifications, affecting the balance between the activating KIR2DS4 and the inhibiting KIR3DL1, with potential benefits on NK cell function.

Impact of exercise on pro inflammatory cytokine levels and epigenetic modulations of tumor-competitive lymphocytes in Non-Hodgkin-Lymphoma patients-randomized controlled trial.

INTRODUCTION: Physical activity is associated with decreased cancer (recurrence) risk and a reduction in treatment-specific side effects. Exercise modulates cytokine expression and shows beneficial effects on cancer patients' immune system. We investigated the following: (i) whether Non-Hodgkin-Lymphoma patients have increased serum macrophage migration inhibiting factor (MIF) and Interleukin-6 (IL-6) levels after immunochemotherapy; (ii) whether physical activity influences cytokine serum levels; and (iii) whether serum cytokine levels are associated with histone modifications in tumor-competitive immune cells. METHODS: Thirty patients and 10 healthy controls were randomised into an intervention and a control group. Participants of the intervention group exercised once for 30 min at moderate intensity on a bicycle ergometer. Blood samples were collected twice, before and after the intervention. MIF and IL-6 serum concentrations were detected by ELISA. Natural killer cells and CD8(+) T-lymphocytes were isolated by magnetic labeled cell sorting. Isolated cells were stained and analyzed for global histone acetylation at histone 4, lysine 5 and histone three, lysine 9. RESULTS: Patients showed higher serum MIF and IL-6 baseline levels, and reduced NK-cell histone acetylation, indicating a reduced transcriptional activity of tumor-competitive lymphocytes. Changes in MIF correlated with altered NK-cell histone acetylation, leading to the hypothesis that MIF impacts NK-cells via epigenetic modifications. Further, the exercise intervention was associated with an increase in IL-6 and CD8(+) T-lymphocyte histone acetylation. CONCLUSIONS: We conclude that exercise induces changes in cytokine levels, thereby possibly affecting epigenetic patterns and activity of tumor-competitive lymphocytes.

DNA barcoding analysis of fish species diversity in four north Greek lakes.

MATERIALS AND METHODS: The present study is the first to apply DNA barcoding on identifying 37 freshwater fish species from the rich Balkan ichthyofauna. RESULTS: The results are highly successful since in most cases barcodes cluster according to species, in agreement with morphological taxonomic studies. This is also evident based on mean conspecific and congeneric Kimura two-parameter distance values. The 5.6-fold difference between these values is lower than previous barcoding studies, possibly due to the restricted samplings and the recent taxonomy reevaluation for several species. A number of species were identified, where future work is needed: For the species Scardinius erythrophthalmus, Perca fluviatilis, and Rutilus rutilus, the divergence values found among conspecific populations could warrant their placement into different species; for Barbus and Rhodeus populations, the reported interspecific distances found were lower than expected; and for Cobitis species, the application of barcoding seems problematic, due to their complicated reproduction. CONCLUSION: The extension of this work to other Greek or even Balkan freshwater systems should clarify the situation.