Increased interleukin-6 production by cerebral cortical tissue of adult versus young mice.
The cytokine interleukin-6 (IL-6) has been implicated as a contributor to injury in several neurological disorders. The amounts of IL-6 released by the cerebral cortical tissue of mice of varying maturational age groups were measured and found to increase with age. Specifically, the basal level of IL-6 released from the tissue of infant (less than 2 weeks old) mice was low, although the tissue could be readily stimulated to secrete high levels of IL-6. Higher levels of IL-6 were released from young adult (2 month old) mice. Adult mice that were either 6 or 9 months of age secreted significantly higher levels of IL-6 compared to the tissue of either the young adult or infant animals, although the difference between levels secreted by the 6- or 9-month old groups was minimal. IL-6 production by adult cerebral cortical tissue could be further stimulated, but it was less readily achieved compared to the tissue of infants. In response to the negative regulator transforming growth factor-beta (TGF-beta), the levels of IL-6 released by stimulated cerebral cortical tissue of infants, as well as by unstimulated and stimulated tissue of adults, were reduced to the low basal levels of IL-6 produced by infant tissue. These results suggest that normal development and aging are correlated with an increase in IL-6 production that may be due to shifts in levels of stimulatory or inhibitory regulatory controls, but not to an inability of young tissue to produce IL-6 or to a lack of responsiveness of adult tissue to negative regulatory control by TGF-beta.
Prechel
M M
MM
Department of Pathology, Loyola University Stritch School of Medicine, Maywood, IL 60153, USA.
Halbur
L
L
Devata
S
S
Vaidya
A M
AM
Young
M R
MR
D000818:Animals; D002540:Cerebral Cortex / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D046508:Culture Techniques; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000494:pharmacology; D015850:Interleukin-6 / Q000096:biosynthesis*; D051379:Mice; D008810:Mice, Inbred C57BL; D013268:Stimulation, Chemical; D016212:Transforming Growth Factor beta / Q000494:pharmacology
D015850:Interleukin-6; D016212:Transforming Growth Factor beta; D016178:Granulocyte-Macrophage Colony-Stimulating Factor