title: Exercise Training Alleviates Hypoxia-induced Mitochondrial Dysfunction in the Lymphocytes of Sedentary Males.
abstract: This study elucidates how interval and continuous exercise regimens affect the mitochondrial functionality of lymphocytes under hypoxic stress. Sixty healthy sedentary males were randomly assigned to engage in either high-intensity interval training (HIIT, 3 min intervals at 80% and 40% VO2max, n = 20) or moderate-intensity continuous training (MICT, sustained 60% VO2max, n = 20) for 30 min/day, 5 days/week for 6 weeks or were assigned to a control group that did not receive exercise intervention (n = 20). Lymphocyte phenotypes/mitochondrial functionality under hypoxic exercise (HE, 100 W under 12% O2) were determined before and after the various interventions. Before the intervention, HE (i) increased the mobilization of senescent (CD57+/CD28-) lymphocytes into the blood, (ii) decreased the ATP-linked O2consumption rate (OCR), the reserve capacity of OCR, and the citrate synthase activity in the mitochondria, and (iii) lowered the mitochondrial membrane potential (MP) and elevated the matrix oxidant burden (MOB) of lymphocytes. However, both HIIT and MICT significantly (i) decreased blood senescent lymphocyte counts, (ii) enhanced the mitochondrial OCR with increased citrate synthase and succinate dehydrogenase activities, (iii) increased mitochondrial MP and decreased MOB and (iv) increased the ratio of mitofusin to DRP-1 in lymphocytes after HE. Thus, we concluded that either HIIT or MICT effectively improves lymphocyte mitochondrial functionality by enhancing oxidative phosphorylation and suppressing oxidative damage under hypoxic conditions.
authors.affiliation: Healthy Aging Research Center, Graduate Institute of Rehabilitation Science, Medical Collage, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Hsing-Hua
authors.initials: HH
authors.lastname: Tsai
authors.affiliation: Healthy Aging Research Center, Graduate Institute of Rehabilitation Science, Medical Collage, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Shao-Chiang
authors.initials: SC
authors.lastname: Chang
authors.affiliation: Healthy Aging Research Center, Graduate Institute of Rehabilitation Science, Medical Collage, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Cheng-Hsien
authors.initials: CH
authors.lastname: Chou
authors.affiliation: Healthy Aging Research Center, Graduate Institute of Rehabilitation Science, Medical Collage, Chang Gung University, Tao-Yuan, Taiwan.
authors.forename: Tzu-Pin
authors.initials: TP
authors.lastname: Weng
authors.affiliation: Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Chih-Chin
authors.initials: CC
authors.lastname: Hsu
authors.affiliation: Healthy Aging Research Center, Graduate Institute of Rehabilitation Science, Medical Collage, Chang Gung University, Tao-Yuan, Taiwan.|Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Keelung, Taiwan.
authors.forename: Jong-Shyan
authors.initials: JS
authors.lastname: Wang
mesh_terms: D002952:Citric Acid Cycle; D004837:Epinephrine / Q000097:blood; D015444:Exercise / Q000502:physiology*; D006019:Glycolysis; D000072696:High-Intensity Interval Training / Q000379:methods; D006801:Humans; D000860:Hypoxia / Q000378:metabolism*; D008214:Lymphocytes / Q000145:classification / Q000378:metabolism*; D008297:Male; D053078:Membrane Potential, Mitochondrial; D008928:Mitochondria / Q000378:metabolism*; D009638:Norepinephrine / Q000097:blood; D001678:Organelle Biogenesis; D010085:Oxidative Phosphorylation; D010101:Oxygen Consumption; D010641:Phenotype; D064797:Physical Conditioning, Human / Q000379:methods; D057185:Sedentary Behavior; D055815:Young Adult
chemical_list: D009638:Norepinephrine; D004837:Epinephrine