Exercise is a double-edged sword: when practiced in moderation, it increases the
expression of antioxidant enzymes, but when practiced strenuously it causes oxidative
stress and cell damage. In this context, polymorphisms in the interleukin (IL)-6 gene
should be investigated better because they can influence performance, at least in
exercise that generates oxidative stress and leads to muscular injuries with
consequent inflammation. In this work, we investigated the influence of IL-6 –174 G/C
polymorphism on tissue damage and inflammation markers, lipid peroxidation, hemogram
and lipid profile of runners before and after ingestion of 400 mg of pequi oil in
capsules supplied daily for 14 consecutive days. The IL-6 genotypes were associated
with significant differences in lipid peroxidation, with the CC mutant having lower
values. There were also significant differences among these genotypes in the response
to supplementation with pequi oil, exercise-induced damage and C-reactive protein
(CRP) levels. The best protection against damage was observed with the heterozygous
genotype. Although the CC genotype showed an increase in CRP levels after
supplementation, the lack of a positive correlation between triglycerides and
high-sensitivity CRP in this mutant genotype after supplementation indicated a
protective effect of pequi. These findings deserve further investigation,
particularly with regard to the quantification of circulating IL-6
concentrations.