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Effect of Pleuran (-glucan from Pleurotus ostreatus) supplementation on cellular immune response after intensive exercise in elite athletes

Canadian Science Publishing
Applied Physiology Nutrition and Metabolism
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Abstract and Figures

Excessive and exhausting physical loads depress the immune system. Carbohydrate consumption may minimize the postexercise suppression of the innate immune system. -Glucan is a well-known immunomodulator, with positive effects on the functioning of immunocompetent cells. The goal of this study was to determine whether -glucan dietary supplementation from the mushroom Pleurotus ostreatus decreases the suppressed immune system responses induced by short-term high-intensity exercise in humans. In this double-blind pilot study, 20 elite athletes were randomized to -glucan (n = 9) or placebo (n = 11) groups these groups consumed 100mg of -glucan (Imunoglukan) or placebo supplements, respectively, once a day for 2months. Venous whole blood was collected before and after 2months of supplementation (baseline), both immediately and 1h after (recovery period) a 20-min intensive exercise bout at the end of the supplementation period. The blood samples were used to measure the cell counts of leukocytes, erythrocyte, and lymphocytes; subpopulations of lymphocytes, granulocytes, and monocytes; and natural killer (NK) cell activity (NKCA). A 28% reduction in NKCA (p< 0.01) below the baseline value was observed in the placebo group during the recovery period, whereas no significant reduction in NKCA was found in the -glucan group. In addition, no significant decrease in NK cell count was measured in the -glucan group during the recovery period. Immune cell counts did not differ significantly between the groups. These results indicate that insoluble -glucan supplementation from P. ostreatus may play a role in modulating exercise-induced changes in NKCA in intensively training athletes.
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Effect of Pleuran (b-glucan from Pleurotus
ostreatus) supplementation on cellular immune
response after intensive exercise in elite athletes
Maria
´n Bobovc
ˇa
´k, Renata Kuniakova
´,Ja
´n Gabriz
ˇ, and Juraj Majta
´n
Abstract: Excessive and exhausting physical loads depress the immune system. Carbohydrate consumption may minimize
the postexercise suppression of the innate immune system. b-Glucan is a well-known immunomodulator, with positive ef-
fects on the functioning of immunocompetent cells. The goal of this study was to determine whether b-glucan dietary sup-
plementation from the mushroom Pleurotus ostreatus decreases the suppressed immune system responses induced by
short-term high-intensity exercise in humans. In this double-blind pilot study, 20 elite athletes were randomized to b-glucan
(n= 9) or placebo (n= 11) groups; these groups consumed 100 mg of b-glucan (Imunoglukan) or placebo supplements, re-
spectively, once a day for 2 months. Venous whole blood was collected before and after 2 months of supplementation
(baseline), both immediately and 1 h after (recovery period) a 20-min intensive exercise bout at the end of the supplementa-
tion period. The blood samples were used to measure the cell counts of leukocytes, erythrocyte, and lymphocytes; subpopu-
lations of lymphocytes, granulocytes, and monocytes; and natural killer (NK) cell activity (NKCA). A 28% reduction in
NKCA (p< 0.01) below the baseline value was observed in the placebo group during the recovery period, whereas no sig-
nificant reduction in NKCA was found in the b-glucan group. In addition, no significant decrease in NK cell count was
measured in the b-glucan group during the recovery period. Immune cell counts did not differ significantly between the
groups. These results indicate that insoluble b-glucan supplementation from P. ostreatus may play a role in modulating ex-
ercise-induced changes in NKCA in intensively training athletes.
Key words: b-glucan, Pleuran, carbohydrate supplement, whole-blood cells, natural killer cells, exercise, innate immunity, athletes.
Re
´sume
´:Des charges physiques trop lourdes et e
´puisantes affaiblissent le syste
`me immunitaire. La consommation de glu-
cides pourrait minimiser l’affaiblissement postexercice du syste
`me immunitaire inne
´.Leb-glucane est un immunomodula-
teur bien connu ayant des effets positifs sur les cellules immunocompe
´tentes. Cette e
´tude se propose de ve
´rifier si une
supple
´mentation alimentaire en b-glucane extrait du Pleurotus ostreatus, un champignon, diminue chez les humains la re
´-
ponse immunode
´pressive du syste
`me immunitaire suscite
´e par un exercice de haute intensite
´et de courte dure
´e. Au cours
d’une e
´tude pilote a
`double insu, on re
´partit ale
´atoirement 20 athle
`tes d’e
´lite en 2 groupes, l’un recevant du b-glucane
(n= 9) et l’autre, un placebo (n= 11). Ces groupes consomment respectivement un supple
´ment de 100 mg de b-glu-
cane (dont l’appellation commerciale est Imunoglukan) ou d’un placebo, et ce, tous les jours sur une pe
´riode de 2
mois. On pre
´le
`ve du sang veineux entier avant et apre
`s 2 mois de supple
´mentation (niveau de re
´fe
´rence) puis imme
´-
diatement apre
`s et 1 h apre
`s (pe
´riode de re
´cupe
´ration) une se
´ance d’exercice intense d’une dure
´e de 20 min a
`la fin
de la pe
´riode de supple
´mentation. On se sert des e
´chantillons sanguins pour la mesure du nombre de leucocytes,
d’e
´rythrocytes, de lymphocytes, de sous-populations de lymphocytes, de granulocytes, de monocytes et de l’activite
´
des cellules tueuses naturelles (NKCA). On observe au cours de la pe
´riode de re
´cupe
´ration du groupe placebo une di-
minution de 28 % de la NKCA (p< 0,01) par rapport au niveau de re
´fe
´rence; on n’observe cependant pas de dimi-
nution significative de la NKCA chez le groupe ayant consomme
´le b-glucane. De plus, on n’observe durant la
pe
´riode de re
´cupe
´ration aucune diminution du nombre de cellules tueuses naturelles chez le groupe ayant consomme
´
le b-glucane. Le nombre de cellules immunitaires ne diffe
`re pas significativement d’un groupe a
`l’autre. D’apre
`s ces
observations, une supple
´mentation en b-glucane extrait du P. ostreatus pourrait avoir un effet dans la modulation de
la NKCA suscite
´e par l’exercice chez des athle
`tes en entraı
ˆnement intensif.
Mots-cle
´s:b-glucane, pleurane, supple
´ment glucidique, cellules de sang entier, cellules tueuses naturelles, exercice
physique, syste
`me immunitaire inne
´, athle
`tes.
[Traduit par la Re
´daction]
Received 12 February 2010. Accepted 25 August 2010. Published on the NRC Research Press Web site at apnm.nrc.ca on 19 November
2010.
M. Bobovc
ˇa
´k. Clinical Laboratory of Institute for Respiratory Disease, 5983 Nova Polianka-High Tatras, Slovakia.
R. Kuniakova
´and J. Gabriz
ˇ.Pleuran, s.r.o, Su
´kennı
´cka 15, 821 09 Bratislava, Slovakia.
J. Majta
´n.1Institute of Zoology, Slovak Academy of Sciences, Du
´bravska
´cesta 9, 845 06 Bratislava, Slovakia; Department of
Microbiology, Slovak Medical University, Limbova 14, 833 03 Bratislava, Slovakia.
1Corresponding author (e-mail: Juraj.Majtan@savba.sk).
755
Appl. Physiol. Nutr. Metab. 35: 755–762 (2010) doi:10.1139/H10-070 Published by NRC Research Press
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Prolonged exercise and heavy training are associated with depressed immune cell function. To maintain immune function, athletes should eat a well-balanced diet sufficient to meet their energy, carbohydrate, protein, and micronutrient requirements. Consuming carbohydrate during prolonged strenuous exercise attenuates rises in stress hormones and appears to limit the degree of exercise-induced immune depression. Recent evidence suggests that antioxidant vitamin supplementation may also reduce exercise stress and impairment of leukocyte functions. Further research is needed to evaluate the effects of other antioxidants and dietary immunostimulants such as probiotics and echinacea on exercise-induced immune impairment.
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(1→3)-β-d-Glucans that have β-d-glucopyranosyl units attached by (1→6) linkages as single unit branches enhance the immune system systemically. This enhancement results in antitumor, antibacterial, antiviral, anticoagulatory and wound healing activities. The (1→3)-β-d-glucan backbone is essential. The most active polymers have degrees of branching (DB) between 0.20 and 0.33. Data suggest both that triple helical structures formed from high molecular weight polymers are possibly important for immunopotentiating activity and that activity is independent of any specific ordered structure. Other data indicate that it is the distribution of the branch units along the backbone chain that is responsible for activity. There are data that indicate both that β-d-glucopyranosyl units are required for immunopotentiating activity and that the specific nature of the substituent is unimportant. There are also data that indicate both that the more water-soluble polymers are more active (up to a certain degree of substitution (DS) or DB) and that some insoluble aggregates are more stimulatory than the soluble polymers. The best conclusion at this time is that the immunopotentiating activity of (1→3)-β-d-glucans depends on a helical conformation and on the presence of hydrophilic groups located on the outside surface of the helix. Immunopotentiation effected by binding of a (1→3)-β-glucan molecule or particle probably includes activation of cytotoxic macrophages, helper T cells, and NK cells, promotion of T cell differentiation, and activation of the alternative complement pathway.