PMID- 16672839
OWN - NLM
STAT- MEDLINE
DCOM- 20061012
LR  - 20061115
IS  - 0195-9131 (Print)
IS  - 0195-9131 (Linking)
VI  - 38
IP  - 5
DP  - 2006 May
TI  - Puberty effects on NK cell responses to exercise and carbohydrate intake in boys.
PG  - 864-74
AB  - Previous research has demonstrated that younger versus older animals and humans 
      experience smaller perturbations in natural killer (NK) cells in response to 
      physiological stress. PURPOSE: To determine whether the smaller perturbations in 
      NK cells induced by strenuous exercise and carbohydrate (CHO) intake, previously 
      reported in children, are influenced by puberty. METHODS: Twenty 12-yr-old boys, 
      distinguished as prepubertal (Tanner (T) 1, N = 7), early pubertal (T2, N = 7), 
      or pubertal (T3-5, N = 6), cycled for 60 min at 70% VO(2max) while drinking 6% 
      CHO (CT) or flavored water (WT). Blood was collected at rest and during (30 and 
      60 min) and following (30 and 60 min) exercise to identify NK cells as 
      CD3(-)CD56(dim) or CD3(-)CD56(dim). CD69 expression on CD3(-)CD56(+) cells was 
      also determined. RESULTS: A puberty x CHO x exercise interaction was found for 
      the proportion, but not number, of CD56(dim) cells (P = 0.06). CD56(dim) cell 
      counts were lower in CT versus WT (P < 0.001). Responses of CD56(bright) 
      proportions (P = 0.007) and counts (P = 0.03) depended on pubertal status, but 
      not CHO. The CD56(bright):CD56(dim) ratio remained stable during exercise, but 
      during recovery was higher in T1 and T3-5 versus T2 (P = 0.08) and in CT versus 
      WT (P = 0.04). During recovery, CD3(-)CD56(+) cells expressed higher levels of 
      CD69 (P = 0.01), with no change in the proportion of CD69(+) cells. CONCLUSION: 
      These results confirm the influence of puberty on the distribution of NK cell 
      subsets in response to exercise and CHO intake. Increased CD69 expression 
      suggests that NK cells increase activation status during recovery from 
      physiological stress.
FAU - Timmons, Brian W
AU  - Timmons BW
AD  - Children's Exercise and Nutrition Centre, McMaster University, Hamilton, Ontario, 
      Canada.
FAU - Tarnopolsky, Mark A
AU  - Tarnopolsky MA
FAU - Snider, Denis P
AU  - Snider DP
FAU - Bar-Or, Oded
AU  - Bar-Or O
LA  - eng
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Med Sci Sports Exerc
JT  - Medicine and science in sports and exercise
JID - 8005433
RN  - 0 (Antigens, CD)
RN  - 0 (Dietary Carbohydrates)
SB  - IM
MH  - Antigens, CD/immunology
MH  - Child
MH  - Dietary Carbohydrates/*administration & dosage
MH  - Exercise/*physiology
MH  - Flow Cytometry
MH  - Humans
MH  - Immunophenotyping
MH  - Killer Cells, Natural/*immunology/physiology
MH  - Male
MH  - Ontario
MH  - *Puberty
EDAT- 2006/05/05 09:00
MHDA- 2006/10/13 09:00
CRDT- 2006/05/05 09:00
PHST- 2006/05/05 09:00 [pubmed]
PHST- 2006/10/13 09:00 [medline]
PHST- 2006/05/05 09:00 [entrez]
AID - 00005768-200605000-00010 [pii]
AID - 10.1249/01.mss.0000218124.87917.40 [doi]
PST - ppublish
SO  - Med Sci Sports Exerc. 2006 May;38(5):864-74. doi: 
      10.1249/01.mss.0000218124.87917.40.