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Evaluation of Serum Oxidized Low-Density Lipoprotein in Renal Transplant Recipients and Hemodialysis Patients and Relation With Involved Variables

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Disturbances in metabolism of lipo-proteins and oxidative modification of low-density lipoprotein contribute to cardiovascular disease and development of oxidative stress in patients under renal replacement therapy (hemodialysis and renal transplant). This study was designed to compare oxidized low-density lipoprotein levels and lipid profiles in renal transplant recipients and hemodialysis patients. We investigated the concentration of oxidized low-density lipoprotein in hemodialysis (n = 38) and renal transplant (n = 59) patients who had no active inflammatory disease, liver disease, or malignancy, and results were compared to a control group (n = 30). Renal transplant recipients had hypercholesterolemia, hypertriglyceridemia, and increased oxidized low-density lipoprotein levels (P = .019) compared with the control group. Hemodialysis patients had moderate hypertriglyceridemia (not significant), hypercholesterolemia, decrease in high-density lipoprotein, and increase in oxidized low-density lipoprotein levels (P < .0001) compared with the control group. In the renal transplant group, oxidized low-density lipoprotein level had a negative correlation with the duration after transplant (r = -0.407; P = .026), positive association with cyclosporine level (r = 0.288; P = .04), and negative correlation with high-density lipoprotein level (r = -.30; P = .05); oxidized low-density lipo-protein/high-density lipoprotein ratio also had a positive correlation with cyclosporine level (r = 0.309; P = .027) and negative correlation with high-density lipoprotein level (r = -0.72; P < .001) in the renal transplant group and high-density lipoprotein in the hemodialysis group (r = -0.87; P < .001). Multiple stepwise regression analyses showed that oxidized low-density lipoprotein only was associated with cyclosporine level (R2 = 0.155; β=0.393; P = .024). History of cardiovascular disease is the most important factor associated with end-stage renal disease, and high oxidized low-density lipoprotein level, oxidized low-density lipo-protein/high-density lipoprotein ratio, and high-density lipoprotein level may affect cardiovascular disease.
... Solatani et al. [31] enrolled 58 ESRD patients undergoing HD that would receive a kidney transplant and found that ox-LDL levels were inversely correlated with the restored kidney function after transplantation and positively with the level of immunosuppressive therapy (cyclosporine). An experimental study showed that in DKD patients, the upregulated ox-LDL expression in podocytes and primary tubular cells induced fibrosis and might be an early event in the onset of the disease [26]. ...
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Diabetic kidney disease (DKD) is a highly heterogenous disease, including the proteinuric and the nonproteinuric pattern. Oxidized low-density lipoprotein (ox-LDL) is progressively increased in DKD and causes direct damage to kidney tubular epithelial cells through a mechanism similar to that underlying the deleterious effect of lipid peroxides in the vascular endothelium. We aimed to examine the association between plasma ox-LDL cholesterol and clinical endpoints in DKD patients. Ninety-one patients with established proteinuric DKD and diabetic retinopathy were enrolled and prospectively followed for 10 years or the occurrence of death, or at least 30% decline in eGFR, or progression to end-stage kidney disease (ESKD) requiring renal replacement therapy (primary outcome). At the end of the study, both eGFR and proteinuria were reassessed. Secondary outcomes of the study were the percentage change in eGFR and proteinuria over time for each patient. At baseline, patients were divided into 2 groups according to the median ox-LDL value (i.e., below or equal and above 66.22 U/L). Both Kaplan-Meier curves (p=0.001, log-rank test) and univariate Cox regression analysis showed that high ox-LDL was associated with the primary outcome (HR=3.42, 95%CI=1.55−7.56, p=0.002). After adjustment for various well-known cofounders, multivariate Cox analysis showed that the association between increased circulating ox-LDL levels and the composite kidney endpoint remained significant (HR=2.87, 95%CI=1.14–7.20, p=0.025). Regarding the secondary outcome of eGFR decline, the assessment of areas under the curves (AUC) showed that ox-LDL outperformed several cofounding factors (AUC 71%, 95%CI=0.59−0.83, p=0.001) and had better accuracy to predict deterioration of eGFR over time than baseline proteinuria (AUC 67%, 95%CI=0.54−0.79, p=0.014). Increased ox-LDL might be associated with disease progression in proteinuric DKD.
... oxLDL has been established as a marker of in vivo lipid peroxidation reflecting increased OS under pathological conditions [19] . To date, several case-control studies have reported increased oxLDL in the general CKD population [9,20] , as well as in AF patients [21] , and recently, oxLDL has been linked to the risk of developing cardiovascular disease in AF patients without associated comorbidities [22] . Our findings extend those observations to the interplay of AF, OS and renal dysfunction. ...
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