Associação entre atividade física, aptidão cardiorrespiratória e biomarcadores inflamatórios em adultos jovens aparentemente saudáveis / Association between physical activity, cardiorespiratory fitness and inflammatory biomarkers in apparently healthy young adults

A inflamação sistêmica crônica de baixa intensidade está relacionada com maior risco de doenças cardiovasculares. Estudos sugerem que a proteína C-reativa, um dos principais biomarcadores inflamatórios, pode estar inversamente relacionada com a prática de atividade física e com a aptidão física. O objetivo deste estudo transversal foi determinar as associações entre os níveis de atividade física e a aptidão cardiorrespiratória, com biomarcadores inflamatórios em homens adultos jovens (18-30 anos) aparentemente saudáveis (N=85). As amostras foram analisadas pelo método ELISA (Enzyme-Linked Immuno Sorbent Assay), usando kits de alta sensibilidade para proteína C-reativa, interleucina 6, interleucina 1? e TNF-?. A prática de atividade física foi mensurada por questionário e acelerometria. O consumo máximo de oxigênio (VO2max) foi estimado por teste incremental em cicloergômetro. Na análise bruta, a média das concentrações de proteína C-reativa da amostra foi de 1,59±1,16 mg/L, e esteve significativamente correlacionada com o VO2max (r=-0,32; p=0,03), mas não com atividade física medida por acelerometria ou questionário. O índice de massa corporal (IMC) e a circunferência abdominal apresentaram correlação significativa com a proteína C-reativa (r=0,37; p<0,001 e r=0,41; p<0,001, respectivamente). Quando incluímos no modelo o IMC e a circunferência da cintura, a aptidão física perdeu a significância. Não houve relação entre atividade física ou aptidão física com os demais marcadores inflamatórios. Conclui-se que nesse grupo de adultos jovens houve relação entre a proteína C-reativa e o VO2max, e que esta associação é explicada pelas modificações no perfil antropométrico decorrentes de altos níveis de aptidão cardiorrespiratória.

Low-intensity chronic systemic inflammation is related to an increased risk of cardiovascular disease. Studies suggest that C-reactive protein, one of the main inflammatory biomarkers, may be inversely related to physical activity levels and physical fitness. The aim of this cross-sectional study was to evaluate the associations between physical activity, fitness and inflammatory biomarkers in apparently healthy men (N=85) aged 18 to 30 years. C-reactive protein, interleukin 6, interleukin 1? and TNF-? were measured using the ELISA method. Physical activity practice was assessed by questionnaire and accelerometry. Maximum oxygen uptake (VO2max) was estimated based on a cycle ergometer incremental test. In the unadjusted analysis, the mean concentration of C-reactive protein in the sample was 1.59±1.16 mg/L, and was inversely correlated with VO2max (r=-0.32, p=0.03), but not with physical activity estimated by accelerometry or questionnaire. Body mass index (BMI) and waist circumference also significantly correlate with C-reactive protein (r=0.37, p<0.001 and r=0.41, p<0.001, respectively). After adjustment for anthropometric characteristics (BMI and waist circumference), the association with fitness was no longer significant. No association was observed between physical activity or fitness levels and the other inflammatory markers. We conclude that in this group of young adults, there was an inverse association between fitness and C-reactive protein, but this association is explained by the influence of fitness on anthropometry.

TP53 gene polymorphism: Importance to cancer, ethnicity and birth weight in a Brazilian cohort.

Arg72Pro SNP of p53 has been associated with many types of cancer as well as with survival and longevity. We evaluated the Arg72Pro SNP frequencies of a Brazilian birth cohort and their association with current, demographic and birth epidemiological parameters available. In 1982, all hospital births of Pelotas, southern Brazil, were identified and studied prospectively. In 2004–5, blood samples were collected and DNA extracted. PCR-RFLP was used to genotype the Arg72Pro SNP in 3794 individual samples of the Brazil birth cohort and DNA sequencing was performed to confirm the genotypes. The genotype distribution, which was in Hardy–Weinberg equilibrium, showed a predominance of the arginine amino acid with a frequency of 46.9% Arg/Arg, 42.2% Arg/Pro and 10.9% Pro/Pro. The allele frequency was 0.68 of Arginine and 0.32 of Proline. The Arg72Pro SNP genotype and allelic frequency were related to skin colour where proline amino acid was observed more among black subjects, while arginine amino acid was observed more among white subjects. The individuals without family history of cancer and those with low birth weight were associated with arginine amino acid. The Arg72Pro SNP was strongly associated with important epidemiological variables confirming that genetic profiles on cohort studies can improve our understanding of the susceptibility of diseases and its risk factors.