Anti-stress action of several orally-given β-glucans.
BACKGROUND
β-Glucans are well-established immunomodulators. Recently, glucans have been found to influence stress-related immunosuppression.


OBJECTIVE
The aim of this study was to compare the effects of four different types of β-glucans on immune reactions suppressed by cold- or restrain-induced stress.


METHODS
Mice were subjected to restraint and cold stress for various time intervals. The ability of individual glucans to overcome stress-related changes was evaluated after 14 days of feeding.


RESULTS
First, we showed that cold stress caused 38% decrease in phagocytic activity. While all glucans showed some ability to inhibit stress-related inhibition, only glucan #300 was able to return the phagocytosis to a normal level. In the control group, feeding with glucans did not alter the level of corticosterone. On the other hand, both types of stress resulted in a significant increase in corticosterone which was blocked to some extent by feeding with glucan. Both types of stress reduced IL-6 secretion but only glucan #300 managed to keep IL-6 secretion above control levels. The same results were obtained in the case of IL-12.


CONCLUSIONS
From our data, we can conclude that, even when all orally-administered glucans helped to restore the stress-related decrease in immune reaction, the level of activity varied widely among individual glucans. In addition, the results suggest that glucans might work via inhibition of corticosterone levels and/or stimulation of cytokine production.
University of Louisville, Department of Pathology, KY, USA. Vaclav.vetvicka@louisville.edu
Vaclav
V
Vetvicka
Zuzana
Z
Vancikova
D000284:Administration, Oral; D000818:Animals; D003080:Cold Temperature; D003345:Corticosterone / Q000097:blood; D016207:Cytokines / Q000096:biosynthesis; D005260:Female; D007108:Immune Tolerance / Q000187:drug effects*; D007155:Immunologic Factors / Q000008:administration & dosage* / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D012149:Restraint, Physical; D013312:Stress, Physiological / Q000276:immunology*; D047071:beta-Glucans / Q000008:administration & dosage* / Q000494:pharmacology
D016207:Cytokines; D007155:Immunologic Factors; D047071:beta-Glucans; D003345:Corticosterone