Abstract
Endurance-training effects on intracellular calcium and iron in CD4+ lymphocytes in young and old men
Medicine and Science in Sports and Exercise, Vol.45(5S), pp.231-231
ACSM Annual Meeting and 4th World Congress on Exercise is Medicine, 60th (Indianapolis, United States, 28-May-2013–01-Jun-2013)
2013
Abstract
Intracellular calcium (Ca2+i )and iron (Fe3+i) are critically involved in intracellular signalling within CD4+ cells yet little is known of long-term exercise effects on these variables in relation to CD4+ activation and proliferation.
PURPOSE: To investigate the effects of 12 months of aerobic/endurance exercise on Ca2+i and Fe3+i concentrations within CD4+ lymphocytes in old and young men compared to sedentary controls.
METHODS: We compared young (30±5 yr) trained (TRY, n=14) and sedentary (UTY, n=12) men to older (69±5 yr) trained (TRO, n=14) and sedentary (UTO, n=10) men for 12 months. The TRY group completed daily endurance training (60-120 min day, 60-80% VO2peak) while the TRO group cycled for three 60 min sessions per week (60-75% VO2peak). Venous blood was analysed every month for resting lymphocyte counts. CD4+ cells were separated and stimulated with thapsigargin to quantify Ca2+i, using Fluo-3 AM and flow cytometry. Further CD4+ lymphocytes were incubated with Calcein AM to assess Fe3+i.
RESULTS: The TRY group had a significantly higher CD4+ concentration than UTY for 4 months (37±7%, p<0.05); no CD4+ count difference between TRO and UTO. Ca2+i was significantly higher in January for all groups (TRY=298±5 nM; UTY=260±15 nM; TRO=160 nM; UTO=210 nM) with significant increases also in September A and July. TRY and UTY had significantly higher peak Ca2+i (70±4%, 20±3%) compared to TRO and UTO. UTO Ca2+i was significantly higher in September A but lower in January compared to TRO; TRY was higher in November compared to UTY. There was an inverse relationship between Ca2+i and Fe3+i, with significantly lower Fe3+i in January-February (all groups), July (TRO, UTO) and September A (TRY, UTY). TRY and UTY (January) had less Fe3+i (-66±6%, -65±6%, p<0.05) than TRO and UTO (February). TRY had significantly higher Fe3+i than UTY in November; UTO had higher Fe3+i than TRO in May.
CONCLUSIONS: Training had little effect on Ca2+i and Fe3+i although CD4+ increased in the TRY group. Significant spikes in Ca2+i and Fe3+i may relate to increased intracellular signalling and/or transcription, and seasonal changes in CD4+ function, during January, July and September. Age-related differences in Ca2+i and Fe3+i may be due to changes in intracellular Ca2+i /Fe3+i storage and signalling with ageing.
Details
- Title
- Endurance-training effects on intracellular calcium and iron in CD4+ lymphocytes in young and old men
- Authors
- Suzanne Broadbent (Author) - Southern Cross University
- Publication details
- Medicine and Science in Sports and Exercise, Vol.45(5S), pp.231-231
- Conference details
- ACSM Annual Meeting and 4th World Congress on Exercise is Medicine, 60th (Indianapolis, United States, 28-May-2013–01-Jun-2013)
- Publisher
- Lippincott Williams & Wilkins
- Date published
- 2013
- DOI
- 10.1249/01.mss.0000433662.68486.39
- ISSN
- 1530-0315; 0195-9131
- Organisation Unit
- University of the Sunshine Coast, Queensland; School of Health - Sports & Exercise Science; School of Health and Behavioural Sciences - Legacy
- Language
- English
- Record Identifier
- 99513780202621
- Output Type
- Abstract
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