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.

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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.

The aim of this study was to assess the relationship between homocysteine (tHcy), folate and vitamin B12 levels, urinary albumin excretion, and arterial blood pressure in patients with non-insulin-dependent diabetes mellitus (NIDDM). Our study was carried out in 33 NIDDM patients (16 men, 17 women) and 16 healthy volunteers as controls (seven men, nine women). Fasting and postmethionine load plasma tHcy levels were assessed, together with folate, vitamin B12, and urinary albumin excretion levels. In NIDDM patients, there were correlations between folate and mean arterial pressure (r = -0.352, P = .046), folate and systolic blood pressure (r = -0.437, P = .013), folate and vitamin B12 (r = 0.499, P = .004), tHcy and vitamin B12 (r = -0.348, P = .04), ln tHcy and ln folate (r = -0.404, P = .01), and, lastly, between tHcy, either fasting or postload, and urinary albumin excretion. Patients with elevated tHcy levels had significantly higher diastolic blood pressure (P = .04) and mean arterial pressure (P = .03). Otherwise, higher folate values were associated with lower systolic blood pressure (P = .004) and mean arterial pressure (P = .02). In addition, NIDDM patients with complications presented higher tHcy basal values than the group without complications (P = .003). A particular propensity of such patients towards endothelial dysfunction could explain the presence of correlations between these metabolic parameters and arterial blood pressure.