title: Exercise intensity and lymphocyte subset apoptosis.
abstract: This investigation assessed the lymphocyte subset response to increasing intensity. Participants completed an exertion test (VO(2max)), and later performed a 10-min run at 76% VO(2max), 5-min at 87%, and run to exhaustion at 100% intensity. Blood was sampled at rest, following each intensity, and 1-h post. Cell concentration, apoptosis (annexin V) and migration (CX₃CR1) were evaluated in CD4+, CD8+, and CD19+ subsets. Relative data were analyzed using 1-way ANOVA with significance at P≤0.05. Absolute changes from rest (Δ baseline) were calculated for exercise conditions. CX₃CR1 displayed relative changes 1-h post, (CD8+ Pre=58%, Post=68%, 1 h-Post=37%, P=0.04) (CD19+ Pre=1.9%, Post=3.2%, 1 h-Post=5.2%, P=0.02). No relative changes were noted for subsets and annexin V. Absolute changes revealed that CD4+/annexin V+ and CD8+/annexin V+ significantly increased at 76%,(P<0.01). Significant absolute increases were observed in CD4+/CX₃CR1 at 87% VO2max, and at 87% and 100% VO2max in CD8+/CX₃CR1 (P<0.01). Subsets respond differently with intensity with respect to cell count, and markers of apoptosis and cell migration. CD4+ and CD8+ appear to be prone to apoptosis with moderate exercise, but significant increases in migration at higher intensities suggests movement of these cells from the vasculature in postexercise measurements.
authors.affiliation: Kinesiology and Nutrition Sciences, University of Nevada-Las Vegas, Las Vegas, NV, USA. james.navalta@unlv.edu
authors.forename: J W
authors.initials: JW
authors.lastname: Navalta
authors.forename: S
authors.initials: S
authors.lastname: Lyons
authors.forename: J
authors.initials: J
authors.lastname: Prestes
authors.forename: S W
authors.initials: SW
authors.lastname: Arnett
authors.forename: M
authors.initials: M
authors.lastname: Schafer
authors.forename: G L
authors.initials: GL
authors.lastname: Sobrero
mesh_terms: D000328:Adult; D018941:Antigens, CD19; D017209:Apoptosis / Q000502:physiology*; D016175:B-Lymphocyte Subsets / Q000502:physiology*; D015496:CD4-Positive T-Lymphocytes / Q000502:physiology; D018414:CD8-Positive T-Lymphocytes / Q000502:physiology; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006801:Humans; D008297:Male; D010807:Physical Endurance; D016176:T-Lymphocyte Subsets / Q000502:physiology*; D057705:Transendothelial and Transepithelial Migration / Q000502:physiology*
chemical_list: D018941:Antigens, CD19