The Influence of the Severity of Early Chronic Kidney Disease on Oxidative Stress in Patients with and without Type 2 Diabetes Mellitus.

Early Chronic Kidney Disease (CKD) is a condition that tends to progress to End-Stage Kidney Disease (ESKD). Early diagnosis of kidney disease in the early stages can reduce complications. Alterations in renal function represent a complication of diabetes mellitus (DM). The mechanisms underlying the progression of CKD in diabetes could be associated with oxidative and inflammatory processes. This study aimed to evaluate the state of inflammation and oxidative stress (OS) on the progression of CKD in the early stages in patients with and without type 2 diabetes mellitus (T2DM). An analytical cross-sectional study was carried out in patients with CKD in early stages (1, 2, 3) with and without T2DM. The ELISA method determined the expression of pro-inflammatory cytokines IL-6 and TNF-α as well as lipoperoxides (LPO), nitric oxide (NO), and superoxide dismutase activity (SOD). Colorimetric methods determined glutathione peroxidase (GPx) and total antioxidant capacity (TAC). Patients with CKD and T2DM had significantly decreased antioxidant defenses for SOD (p < 0.01), GPx (p < 0.01), and TAC (p < 0.01) compared to patients without T2DM. Consequently, patients with T2DM had higher concentrations of oxidant markers, NO (p < 0.01), inflammation markers, IL-6 (p < 0.01), and TNF-α than patients without T2DM. CKD stages were not related to oxidative, antioxidant, and inflammatory marker outcomes in T2DM patients. Patients without T2DM presented an increase in SOD (p = 0.04) and a decrease in NO (p < 0.01) when the stage of CKD increased. In conclusion, patients with T2DM present higher levels of oxidative and inflammatory markers accompanied by a decrease in antioxidant defense. However, these oxidative status markers were associated with CKD stage progression in patients without T2DM. Thus, NO and SOD markers could help detect the early stages of CKD in patients who have not yet developed metabolic comorbidities such as T2DM.

The Effect of Enalapril, Losartan, or Not Antihypertensive on the Oxidative Status in Renal Transplant Recipients.

The clinical and biochemical improvement observed in kidney transplant (RT) recipients is remarkable. The correct functioning of the allograft depends on various factors such as the donor's age, the alloimmune response, the ischemia-reperfusion injury, arterial hypertension, and the interstitial fibrosis of the allograft, among others. Antihypertensive drugs are necessary for arterial hypertension patients to avoid or reduce the probability of affecting graft function in RT recipients. Oxidative stress (OS) is another complex pathophysiological process with the ability to alter posttransplant kidney function. The study's objective was to determine the effect of the administration of Enalapril, Losartan, or not antihypertensive medication on the oxidative state in RT recipients at the beginning of the study and one year of follow-up. All patients included in the study found significant overexpression of the oxidative damage marker to DNA and the antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx). In contrast, it was found that the determination of the total antioxidant capacity decreased significantly in the final determination at one year of follow-up in all the patients who ingested Enalapril and Losartan. We found dysregulation of the oxidative state characterized mainly by oxidative damage to DNA and a significant increase in antioxidant enzymes, which could suggest a compensatory effect against the imbalance of the oxidative state.

The Influence of Sevelamer Hydrochloride and Calcium Carbonate on Markers of Inflammation and Oxidative Stress in Hemodialysis at Six Months of Follow-Up.

Patients with end-stage renal disease (ESRD) present alterations in mineral and bone metabolism. Hyperphosphatemia in ESRD is considered an independent risk factor for cardiovascular disease (CVD), increasing morbidity, and mortality. Sevelamer hydrochloride is a calcium-free, non-absorbable phosphate-chelating polymer. Calcium carbonate chelator is helpful in controlling serum phosphate levels. There is insufficient information on the influence of sevelamer hydrochloride and calcium carbonate on the behavior of oxidative stress (OS) markers and inflammation in patients on hemodialysis (HD). A randomized open clinical trial was carried out on patients to evaluate sevelamer hydrochloride and calcium carbonate influence at 6 months of study follow-up. Levels of oxidants (LPO, NO, and 8-isoprostanes), antioxidants (SOD and TAC), oxidative DNA damage (8-OHdG and hOGG1), pro-inflammatory cytokines (IL-6 and TNF-α), and inflammation markers (ferritin and C-reactive protein) were measured with colorimetric and ELISA methods. We found a significant increase in oxidants LPO and NO, and antioxidants SOD and TAC, and downregulation of IL-6 and TNF-α. Ferritin decrease at 6 months follow-up in the sevelamer hydrochloride group. Increase in C-reactive protein was found in the group of patients treated with calcium carbonate. In conclusion, we found an oxidative state imbalance with increase in LPO and NO oxidants. The activity of the antioxidant enzymes (SOD and TAC) was also found to increase, suggesting a compensatory effect in the face of increase in oxidants. The same phenomenon was observed with increase in the oxidative damage marker to DNA and the increase in the DNA repair enzyme, suggesting a compensatory effect. Pro-inflammatory cytokines were predominantly downregulated by TNF-α in the group that ingested sevelamer hydrochloride in the final determination at 6 months of follow-up. Serum ferritin levels decreased significantly at the end of follow-up in patients on HD in the sevelamer hydrochloride group. The management of hyperphosphatemia with sevelamer hydrochloride appears to have obvious anti-inflammatory and antioxidant benefits.

The Alteration of Pro-inflammatory Cytokines and Oxidative Stress Markers at Six-Month Post-living Kidney Donation.

Donors have a higher risk of developing chronic kidney disease than the general population. Some mechanisms mediated by pro-inflammatory cytokines and oxidative stress may be involved as risk factors. The objective of the study was to evaluate the behavior of pro-inflammatory cytokines and oxidative stress markers in living renal donors with a 6-month follow-up. A single prospective cohort was performed in 88 renal donors. At the end of the follow-up, the levels of lipoperoxides, 6.52 ± 1.12 mM, and 8-isoprostanes, 63.75 ± 13.28 pg/mL, were lower than before donation, 10.20 ± 3.95 mM (p < 0.001) and 67.54 ± 9.64 pg/mL (p = 0.026), respectively. Initial levels of nitric oxide (NO), 356.09 ± 59.38 µM increased at the end of the follow-up, 467.08 ± 38.74 µM (p < 0.001). It was observed in the final determination of donors decreased activity of antioxidant enzymes superoxide dismutase (SOD), 0.74 ± 0.57 U/L and glutathione peroxidase (GPx), 556.41 ± 80.37 nmol, in comparison with the levels obtained in the initial determination, 1.05 ± 0.57 U/L (p < 0.001) and 827.93 ± 162.78 nmol (p < 0.001), respectively. The pro-inflammatory cytokines, Tumor necrosis factor alpha and interleukin-6 showed no differences at 6 months after donation. The enzyme oxoguanine glycosylase (hOGG1) responsible for repairing oxidative damage to DNA, showed a decrease in its concentration at the end of the study in donor men, 0.40 ± 0.21 ng/mL compared to the initial levels, 0.55 ± 0.32 ng/mL (p = 0.025). The marker, 8-hydroxy-2-deoxyguanosine (8-OHdG) exhibited an increase in donor men at the final determination 2.28 ± 1.99 ng/mL, compared to the concentration before donation, 1.72 ± 1.96 ng/mL (p < 0.001). We found significant changes in the markers of the oxidative state with increased NO and 8-OHdG, as well as a significant decrease in the antioxidant defenses SOD, GPx, and in the DNA repair enzyme in living renal donors after 6 months of follow-up.

The Effect of Visceral Abdominal Fat Volume on Oxidative Stress and Proinflammatory Cytokines in Subjects with Normal Weight, Overweight and Obesity.

PURPOSE: The increase of visceral abdominal fat (VAF) and oxidative stress (OS) are independent predictors for cardiovascular risk. This study aimed to determine the association of VAF with proinflammatory cytokines, oxidants, antioxidants, and oxidative damage to DNA in subjects with normal weight, overweight, and obesity. PATIENTS AND METHODS: A cross-sectional study that included 21 men and 71 women who attended for a medical check-up was conducted. Dual-energy X-ray absorptiometry (DXA) was used to measure the VAF volume. ELISA and colorimetric techniques were used for chemical analysis. RESULTS: Low activity of superoxide dismutase (SOD) was found in overweight and obese subjects compared to the normal weight group (p=0.005). In contrast, the activity of glutathione peroxidase (GPx) was higher in the overweight and obesity groups compared to the normal weight subjects (p=0.017). The total antioxidant capacity (TAC) was also increased in the overweight group compared to the normal weight group (p=0.04). According to the volume of VAF, the levels of tumor necrosis factor alfa and interleukin 6 showed no differences between subjects with normal and high VAF. Subjects with high VAF show higher levels of 8-isoprostans compared to normal VAF group (p=0.039). Less concentration of 8-oxoguanine-DNA-N-glycosylase-1 (hOGG1) was found in the high VAF group (p=0.032) compared to the normal VAF subjects. VAF was positively correlated with lipoperoxides (LPO) (r=0.27, p<0.05) and 8-isoprostanes (r=0.25, p<0.05). We also found correlations between oxidative stress markers and anthropometric ratios for intra-abdominal fat. The waist-hip ratio was positively correlated with LPO (r=0.30, p<0.05) and TAC (r=0.24, p<0.05). CONCLUSION: These findings suggest that the predominantly oxidative damage associated with VAF in overweight or obesity is lipoperoxidation and oxidative DNA damage. Alterations in endogenous antioxidant defenses may not be linked to the amount of VAF.