title: Effects of aerobic training on markers of autophagy in the elderly.
abstract: Autophagy is a molecular process essential for the maintenance of cellular homeostasis, which appears to (i) decline with age and (ii) respond to physical exercise. In addition, recent evidence suggests a crosstalk between autophagy and toll-like receptor (TLR)-associated inflammatory responses. This study assessed the effects of aerobic exercise training on autophagy and TLR signaling in older subjects. Twenty-nine healthy women and men (age, 69.7 ± 1.0 year) were randomized to a training (TG) or a control (CG) group. TG performed an 8-week aerobic training program, while CG followed their daily routines. Peripheral blood mononuclear cells were isolated from blood samples obtained before and after the intervention, and protein levels of protein 1 light chain 3 (LC3), sequestosome 1 (p62/SQSTM1), beclin-1, phosphorylated unc-51-like kinase (ULK-1), ubiquitin-like autophagy-related (Atg)12, Atg16, and lysosome-associated membrane protein (LAMP)-2 were measured. TLR2 and TLR4 signaling pathways were also analyzed. Peak oxygen uptake increased in TG after the intervention. Protein expression of beclin-1, Atg12, Atg16, and the LC3II/I ratio increased following the training program (p < 0.05), while expression of p62/SQSTM1 and phosphorylation of ULK-1 at Ser(757) were lower (p < 0.05). Protein content of TLR2, TLR4, myeloid differentiation primary response gen 88 (MyD88), and TIR domain-containing adaptor-inducing interferon (TRIF) were not significantly modified by exercise. The current data indicate that aerobic exercise training induces alterations in multiple markers of autophagy, which seem to be unrelated to changes in TLR2 and TLR4 signaling pathways. These results expand knowledge on exercise-induced autophagy adaptations in humans and suggest that the exercise type employed may be a key factor explaining the potential relationship between autophagy and TLR pathways.
authors.affiliation: Institute of Biomedicine (IBIOMED), University of León, Campus Vegazana s/n, 24071, León, Spain.
authors.forename: Yubisay
authors.initials: Y
authors.lastname: Mejías-Peña
authors.affiliation: Divisions of Clinical and Translational Sciences, Georgia Prevention Institute, Department of Pediatrics, Augusta University, Augusta, USA.
authors.forename: Paula
authors.initials: P
authors.lastname: Rodriguez-Miguelez
authors.affiliation: Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Fernandez-Gonzalo
authors.affiliation: Institute of Biomedicine (IBIOMED), University of León, Campus Vegazana s/n, 24071, León, Spain.
authors.forename: Susana
authors.initials: S
authors.lastname: Martínez-Flórez
authors.affiliation: Institute of Biomedicine (IBIOMED), University of León, Campus Vegazana s/n, 24071, León, Spain.
authors.forename: Mar
authors.initials: M
authors.lastname: Almar
authors.affiliation: Institute of Biomedicine (IBIOMED), University of León, Campus Vegazana s/n, 24071, León, Spain.
authors.forename: José A
authors.initials: JA
authors.lastname: de Paz
authors.affiliation: Institute of Biomedicine (IBIOMED), University of León, Campus Vegazana s/n, 24071, León, Spain.
authors.forename: María J
authors.initials: MJ
authors.lastname: Cuevas
authors.affiliation: Institute of Biomedicine (IBIOMED), University of León, Campus Vegazana s/n, 24071, León, Spain. jgonga@unileon.es.
authors.forename: Javier
authors.initials: J
authors.lastname: González-Gallego
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism*; D001343:Autophagy / Q000502:physiology*; D015415:Biomarkers / Q000097:blood*; D015153:Blotting, Western; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010809:Physical Fitness / Q000502:physiology*; D015398:Signal Transduction; D051197:Toll-Like Receptor 4 / Q000097:blood; D055815:Young Adult
chemical_list: D015415:Biomarkers; D051197:Toll-Like Receptor 4
keywords: Autophagy; Elderly; High-intensity interval training; TLR