Effect of eicosapentaenoic acid intake on the relationship between lnterleukin-6 and acute phase proteins in serum in youths.

Twenty male volunteers 20-25 years old were examined to determine their serum concentrations of interleukin-6 (IL-6), acute phase proteins and lipids before, immediately after and one hour after a load of 90 watts for 20 minutes using a Monark ergometer, and the same parameters were reexamined after eicosapentaenoic acid (EPA) intake of 1.125 g/day for 2 weeks. By EPA intake, EPA level of the membranes of red blood cells increased significantly by 75.6% and docosahexanoic acid (DHA) by 53.8%. The IL-6 level increased significantly by 17% and C-reactive protein (CRP) by 11.7%, but fibrinogen (Fbg) decreased by 9.6%. After EPA intake, at one hour after the load, the change rate of IL-6 decreased to that of before EPA. The change rate of α(1)-acid glycoprotein ( α(1)-AGP) increased in the group in which IL-6 was unchanged and did so significantly in the group in which it increased, but tended to increase in the group in which it decreased. Thus the change rate of sialic acids (SA) increased significantly in both the IL-6 unchanged and increased groups. It is suggested that EPA activated IL-6, which was related to the increase of α(1)-AGP as an activator of immunity. The change rate of sialic acid (SA) as an index of acute phase protiens was correlated significantly and positively with that of total cholesterol and HDL-cholesterol.