Ana Paula de Queiroz Mello

Electronegative low-density lipoprotein: Origin and impact on health and disease

Oxidative modifications in lipoproteins (LP), especially in low-density lipoproteins (LDL), are associated with initiation and progression of atherosclerosis. The levels of a sub-fraction of LDL with oxidative characteristics, named electronegative LDL [LDL(-)], minimally oxidized LDL, and minus LDL, are known to be increased in subjects with familial hypercholesterolemia, hypertriglyceridemia, nonalcoholic steatohepatitis, diabetes mellitus, coronary artery disease, patients undergoing hemodialysis, and athletes after aerobic exercise. In addition to the oxidative profile, physical and biological characteristics of LDL(-) consist of nonenzymatic glycosylation, increased expression and activity of platelet-activating factor acetylhydrolase (PAF-AH) and phospholipase A(2) (PLA(2)), enriched NEFA content, hemoglobin and ApoB-100 cross-linking, and increase in ApoC-III and ApoE in LDL. Herein, we summarize the state of the art of the up-to-date body of knowledge on the possible origin and impact of LDL(-) in health and disease. Further, the potential perspectives of using LDL(-) as a biomarker in conditions under metabolic stress are also discussed.

Antioxidant and inflammatory aspects of lipoprotein-associated phospholipase A2 (Lp-PLA2 ): a review

The association of cardiovascular events with Lp-PLA2 has been studied continuously today. The enzyme has been strongly associated with several cardiovascular risk markers and events. Its discovery was directly related to the hydrolysis of the platelet-activating factor and oxidized phospholipids, which are considered protective functions. However, the hydrolysis of bioactive lipids generates lysophospholipids, compounds that have a pro-inflammatory function. Therefore, the evaluation of the distribution of Lp-PLA2 in the lipid fractions emphasized the dual role of the enzyme in the inflammatory process, since the HDL-Lp-PLA2 enzyme contributes to the reduction of atherosclerosis, while LDL-Lp-PLA2 stimulates this process. Recently, it has been verified that diet components and drugs can influence the enzyme activity and concentration. Thus, the effects of these treatments on Lp-PLA2 may represent a new kind of prevention of cardiovascular disease. Therefore, the association of the enzyme with the traditional assessment of cardiovascular risk may help to predict more accurately these diseases.

Impacto da proteína-C reativa no risco cardiovascular de adolescentes

BACKGROUND Several studies suggest that C-reactive protein (CRP) is associated with coronary artery disease in adults. However, this association has not been thoroughly explored in cases of adolescents. OBJECTIVE To evaluate the association between CRP and cardiovascular risk factors in obese adolescents. METHODS Eighty-four adolescents (12.6 +/- 1.3 years) of both genders were divided into the following groups: Normal weight (n = 28), Overweight (n = 28), and Obese (n = 28), according to body mass index (BMI). CRP levels (ultrasensitive ELISA), the lipid profile, and anti-oxLDL antibody levels (ELISA) were determined after a 12-hour fast. RESULTS The groups were similar in age (p = 0.13) and gender (p = 0.83). Total cholesterol, HDL-C, TC/HDL-C, and LDL-C/HDL-C showed significant differences between Normal weight and Obese groups. There was no significant variation in anti-oxLDL levels. CRP values were different among the three groups (p < 0.01). CRP levels showed a significant association with BMI (beta = 2.533), AC (beta = 2.645), WC (beta = 2.945), TC (beta = 0.006), LDL-C (beta = 0.006), and anti-oxLDL antibodies (beta = 0.383), and a negative association with HDL-C (beta = -0.017). CONCLUSION The results indicate that CRP is significantly associated with markers of cardiovascular risk in adolescents.FUNDAMENTO: Varios estudos sugerem que a proteina-C reativa (PCR) se correlaciona com doenca arterial coronariana em adultos. Entretanto, essa associacao ainda e pouco explorada em adolescentes. OBJETIVO: Avaliar a associacao entre a PCR e os fatores de risco cardiovascular em adolescentes obesos. METODOS: Oitenta e quatro adolescentes (12,6 ± 1,3 anos), ambos os sexos, foram distribuidos nos grupos Eutrofico (n = 28), Sobrepeso (n = 28) e Obeso (n = 28), segundo o indice de massa corporea (IMC). A concentracao de PCR (ELISA ultrassensivel), o perfil lipidico e o conteudo de anticorpos anti-LDLox (ELISA) foram determinados apos jejum de 12h. RESULTADOS: Os grupos foram semelhantes quanto a idade (p = 0,13) e sexo (p = 0,83). Colesterol total, HDL-C, CT/HDL-C e LDL-C/HDL-C apresentaram diferencas significativas entre os grupos Eutrofico e Obeso. Nao houve variacao significativa no conteudo de anticorpos anti-LDLox. Os valores de PCR foram diferentes entre os tres grupos (p < 0,01). PCR apresentou associacao significativa com IMC (β = 2,533), CB (β = 2,645) e CC (β = 2,945), CT (β = 0,006), LDL-C (β = 0,006) e anticorpos anti-LDLox (β = 0,383) e negativa entre HDL-C (β = -0,017). CONCLUSAO: Os resultados indicam que a PCR se associa significativamente com marcadores de risco cardiovascular em adolescentes.

Fish oil and vitamin E change lipid profiles and anti-LDL-antibodies in two different ethnic groups of women transitioning through menopause

BACKGROUND studies have investigated the relationship between the transition through menopause and cardiovascular diseases. White population, generally, have lower levels of traditional coronary heart risk factors, particularly dyslipidemia, hypertension, obesity, and diabetes, and lower rates of coronary heart disease mortality, than black population. Furthermore many studies have shown the cardioprotective and anti-inflammatory effects of omega-3 polyunsaturated fatty acids (eicosapentaenoic acid and docosahexaenoic acid) of marine origin. The aim of this study was to investigate the effect of omega-3 supplementation, combined or not with vitamin E, on oxidative biomarkers and lipid profiles in nonwhite and white women with dyslipidemia transitioning through menopause. METHODS a randomized, double-blind, placebo-controlled trial was conducted. Seventy-four eligible women were assigned to receive: fish oil, fish oil plus vitamin E and placebo for three months. At baseline, 45 and 90 days blood sample for biochemical variables and biomarkers of oxidative stress were taken. Socioeconomic and lifestyle variables were collected with standardized questionnaires. RESULTS after 90 days the fish oil plus vitamin E treated group had a significant decrease in total cholesterol and LDL-C. Furthermore, there was a decrease in anti- LDL- autoantibodies after 45 days. Plasma TBARS concentrations were increased after 90 days in the group receiving only fish oil when compared to the placebo and fish oil-vitamin E groups. All of the effects observed were independent of ethnic group. CONCLUSION supplementation with fish oil and vitamin E reduced total cholesterol and LDL-C, but had opposite effects on oxidative stress compared to supplementation with fish oil alone.

Impact of C-reactive protein on cardiovascular risk in adolescents

BACKGROUND Several studies suggest that C-reactive protein (CRP) is associated with coronary artery disease in adults. However, this association has not been thoroughly explored in cases of adolescents. OBJECTIVE To evaluate the association between CRP and cardiovascular risk factors in obese adolescents. METHODS Eighty-four adolescents (12.6 +/- 1.3 years) of both genders were divided into the following groups: Normal weight (n = 28), Overweight (n = 28), and Obese (n = 28), according to body mass index (BMI). CRP levels (ultrasensitive ELISA), the lipid profile, and anti-oxLDL antibody levels (ELISA) were determined after a 12-hour fast. RESULTS The groups were similar in age (p = 0.13) and gender (p = 0.83). Total cholesterol, HDL-C, TC/HDL-C, and LDL-C/HDL-C showed significant differences between Normal weight and Obese groups. There was no significant variation in anti-oxLDL levels. CRP values were different among the three groups (p < 0.01). CRP levels showed a significant association with BMI (beta = 2.533), AC (beta = 2.645), WC (beta = 2.945), TC (beta = 0.006), LDL-C (beta = 0.006), and anti-oxLDL antibodies (beta = 0.383), and a negative association with HDL-C (beta = -0.017). CONCLUSION The results indicate that CRP is significantly associated with markers of cardiovascular risk in adolescents.FUNDAMENTO: Varios estudos sugerem que a proteina-C reativa (PCR) se correlaciona com doenca arterial coronariana em adultos. Entretanto, essa associacao ainda e pouco explorada em adolescentes. OBJETIVO: Avaliar a associacao entre a PCR e os fatores de risco cardiovascular em adolescentes obesos. METODOS: Oitenta e quatro adolescentes (12,6 ± 1,3 anos), ambos os sexos, foram distribuidos nos grupos Eutrofico (n = 28), Sobrepeso (n = 28) e Obeso (n = 28), segundo o indice de massa corporea (IMC). A concentracao de PCR (ELISA ultrassensivel), o perfil lipidico e o conteudo de anticorpos anti-LDLox (ELISA) foram determinados apos jejum de 12h. RESULTADOS: Os grupos foram semelhantes quanto a idade (p = 0,13) e sexo (p = 0,83). Colesterol total, HDL-C, CT/HDL-C e LDL-C/HDL-C apresentaram diferencas significativas entre os grupos Eutrofico e Obeso. Nao houve variacao significativa no conteudo de anticorpos anti-LDLox. Os valores de PCR foram diferentes entre os tres grupos (p < 0,01). PCR apresentou associacao significativa com IMC (β = 2,533), CB (β = 2,645) e CC (β = 2,945), CT (β = 0,006), LDL-C (β = 0,006) e anticorpos anti-LDLox (β = 0,383) e negativa entre HDL-C (β = -0,017). CONCLUSAO: Os resultados indicam que a PCR se associa significativamente com marcadores de risco cardiovascular em adolescentes.

Impacto de la Proteína-C reactiva en el riesgo cardiovascular de adolescentes

BACKGROUND Several studies suggest that C-reactive protein (CRP) is associated with coronary artery disease in adults. However, this association has not been thoroughly explored in cases of adolescents. OBJECTIVE To evaluate the association between CRP and cardiovascular risk factors in obese adolescents. METHODS Eighty-four adolescents (12.6 +/- 1.3 years) of both genders were divided into the following groups: Normal weight (n = 28), Overweight (n = 28), and Obese (n = 28), according to body mass index (BMI). CRP levels (ultrasensitive ELISA), the lipid profile, and anti-oxLDL antibody levels (ELISA) were determined after a 12-hour fast. RESULTS The groups were similar in age (p = 0.13) and gender (p = 0.83). Total cholesterol, HDL-C, TC/HDL-C, and LDL-C/HDL-C showed significant differences between Normal weight and Obese groups. There was no significant variation in anti-oxLDL levels. CRP values were different among the three groups (p < 0.01). CRP levels showed a significant association with BMI (beta = 2.533), AC (beta = 2.645), WC (beta = 2.945), TC (beta = 0.006), LDL-C (beta = 0.006), and anti-oxLDL antibodies (beta = 0.383), and a negative association with HDL-C (beta = -0.017). CONCLUSION The results indicate that CRP is significantly associated with markers of cardiovascular risk in adolescents.FUNDAMENTO: Varios estudos sugerem que a proteina-C reativa (PCR) se correlaciona com doenca arterial coronariana em adultos. Entretanto, essa associacao ainda e pouco explorada em adolescentes. OBJETIVO: Avaliar a associacao entre a PCR e os fatores de risco cardiovascular em adolescentes obesos. METODOS: Oitenta e quatro adolescentes (12,6 ± 1,3 anos), ambos os sexos, foram distribuidos nos grupos Eutrofico (n = 28), Sobrepeso (n = 28) e Obeso (n = 28), segundo o indice de massa corporea (IMC). A concentracao de PCR (ELISA ultrassensivel), o perfil lipidico e o conteudo de anticorpos anti-LDLox (ELISA) foram determinados apos jejum de 12h. RESULTADOS: Os grupos foram semelhantes quanto a idade (p = 0,13) e sexo (p = 0,83). Colesterol total, HDL-C, CT/HDL-C e LDL-C/HDL-C apresentaram diferencas significativas entre os grupos Eutrofico e Obeso. Nao houve variacao significativa no conteudo de anticorpos anti-LDLox. Os valores de PCR foram diferentes entre os tres grupos (p < 0,01). PCR apresentou associacao significativa com IMC (β = 2,533), CB (β = 2,645) e CC (β = 2,945), CT (β = 0,006), LDL-C (β = 0,006) e anticorpos anti-LDLox (β = 0,383) e negativa entre HDL-C (β = -0,017). CONCLUSAO: Os resultados indicam que a PCR se associa significativamente com marcadores de risco cardiovascular em adolescentes.