Polymorphisms in PPARG and APOE: relationships with lipid profile of adolescents with cardiovascular risk factors

BACKGROUND: Cardiovascular diseases constitute the main death cause worldwide resulting from a combination of genetic and lifestyle factors, and the prevalence among younger individuals has increased. It is important to early identify changes in lipid profile and the influence of genetic variations in specific genes on the individual patterns of lipid profile. Thus, the aim of this study was to verify the relationship of polymorphisms in PPAR-gamma gene (PPARG−rs1801282−Pro12Ala) and in apolipoprotein E gene (APOE−rs429358 + rs7412, determinants of the APOE2, APOE3, or APOE4 genotypes) with lipid profile of adolescents under cardiovascular risk factors. METHODS: This was a cross-sectional study with 115 adolescents aged 10­19 years, which presented cardiovascular risk factors. The students were evaluated regarding socioeconomic, anthropometric, biochemical, genetic, and dietetic variables. Student'sttest or Mann-Whitney test were applied to the analysis of the genotypes. Multiple linear regression analysis was performed to determine the variables that most influenced the lipid profile. RESULTS: Adolescents carrying PPARG Ala allele showed higher serum triglycerides (p= 0.0423) and very low-density lipoprotein (p= 0.0410) levels when compared to those carrying the wild genotype. For the APOE polymorphism, it was observed a trend of higher triglycerides (p= 0.0712) and very low-density lipoprotein (p= 0.0758) levels in the adolescents carrying the E4 allele when compared to those who did not carry this allele. CONCLUSION: The polymorphisms PPARGrs1801282 andAPOErs429358 + rs7412 seem to be related to the development of lipid profile alterations in adolescents.

Development of immunoassays for anti-electronegative LDL autoantibodies and immune complexes.

BACKGROUND: Electronegative low-density lipoprotein (LDL-) promotes atherosclerosis through inflammatory and immunologic mechanisms that lead to the production of anti-LDL(-) autoantibodies and to the subsequent formation of immune complexes (IC) and macrophage foam cells. We described the development and validation of an ELISA for the quantification of free anti-LDL(-) autoantibodies and an ELISA for the quantification of IC consisting of LDL(-)-bound IgG in human plasma. METHODS: LDL(-) purified from human plasma, and anti-LDL(-) monoclonal antibody Fab fragments were adsorbed onto ELISA plates to capture anti-LDL(-) autoantibodies and IC-LDL(-), respectively. The performance characteristics of both ELISAs, including the limits of detection and quantification, accuracy and inter- and intra-assay precision were evaluated. Linearity, interference and stability tests were also performed. RESULTS: The calibration range of the anti-LDL(-) assay was 0.004-0.125 mU/l and plasma demonstrated a dilutional linearity when diluted 1:100, 1:200, 1:400 and 1:800. The calibration range of the IC-LDL(-) assay was 0.06-4 U/l, and plasma demonstrated a dilutional linearity when diluted 1:12.5, 1:25, 1:50 and 1:100. Both ELISAs showed intra- and inter-assay precision and recovery within the required limits for immunoassays. CONCLUSION: These ELISAs can be used in clinical studies and for the biochemical investigation of atherosclerosis. In addition, they will enable the comprehensive evaluation of the importance of bound or free autoantibodies against LDL(-) in this disease.