Reactive oxygen species have been implicated in the pathophysiology of renal ischemia reperfusion injury. Antioxidants including polyphenolics have been found to protect renal cells from the cellular injury induced by ischemia and reperfusion. Resveratrol, a stilbene polyphenol found in grapes and red wine, has recently been found to protect isolated rat heart from ischemia reperfusion injury. This study was sought to determine if resveratrol could also protect renal cells from ischemic injury. Male Wistar rats were treated with control, resveratrol (0.23 microg/kg), vehicle used to solubilize resveratrol, and resveratrol plus L-NAME (15 mg/kg body wt), a nitric oxide blocker. Our results demonstrated that resveratrol administration reduced the mortality of ischemic rats from 50% to 10% and renal damage was reduced as indicated by histologic examination and serum creatinine level. The short-term administration of resveratrol also inhibited renal lipid peroxidation induced by ischemia and reperfusion both in cortex and in medulla. Electron paramagnetic resonance detected an increased formation of nitric oxide in the resveratrol-treated kidney that was reduced to the baseline value after treating the rats with L-NAME in addition to resveratrol. The results suggest that resveratrol reduced the renal ischemia reperfusion injury through a nitric oxide-dependent mechanism.

1,25(OH)2D3 can reduce glomerular hypercellularity, inflammatory infiltration in anti-Thy-1.1 nephritis, preserving the apoptotic response of the reparative phase.

We characterized the overall early effect of chronic ochratoxin A (OTA) treatment on rat liver, analyzing different aspects related to: (i) fibrosis, by measuring collagen content and turnover, and ␣-smooth muscle actin (␣SMA); (ii) oxidative stress and stress response, by analyzing protein carbonylation, superoxide dismutase (SOD) and heat shock protein (HSP70) gene expression; (iii) the possible tumor promoter effect, evaluating cadherin and connexin (CX) mRNA levels. Light microscopy analysis showed no histological differences in OTA-treated and control (CT) rats. Collagen content, determined by computer analysis of Sirius redstained liver sections, was similar in both groups. In liver homogenates COL-I, COL-III, TIMP-1 and TGF-␤1 mRNA levels and ␣SMA were unaffected by OTA. Matrix metalloproteinase (MMP)-1, MMP-2 and MMP-9 protein levels were also similar in the two groups. Protein carbonylation, a marker of severe oxidative stress, was not evident in the homogenates of OTA-treated livers; superoxide dismutase (SOD) mRNA tended to be lower and HSP70 was strongly down-regulated. OTA reduced E-cadherin and DSC-2 transcription, and down-regulated liver CX26, CX32 and CX43. In conclusion, these in vivo results show that OTA-induced liver injury involves a reduction in the ability to counterbalance oxidative stress, maybe leading to altered gap junction intercellular communication and loss of cell adhesion and polarity. This suggests that mild oxidative damage might be a key factor, in combination with other cytotoxic effects, in triggering the promotion of liver tumors after exposure to OTA.

Haemodiafiltration with online regeneration of ultrafiltrate and online HDF are highly biocompatible techniques and no significant difference between HFR and online HDF was observed in terms of reduction of inflammatory markers. Further studies with a longer follow-up are needed to evaluate the clinical relevance of the online endogenous reinfusion to counteract the chronic inflammatory state of the uraemic patient.

In this study, we investigated the effect of 1,25(OH)2D3 on proteinuria and on the alteration of slit diaphragm-associated proteins induced by anti-Thy 1.1 in Wistar rats. Four groups of animals were studied: group I, anti-Thy 1.1 treated rats; group II, anti-Thy1.1 treated group that at day 2, after the onset of overt proteinuria, started the treatment with 1,25(OH)2D3; group III, normal control rats injected with vehicle alone; group IV, rats that received only 1,25(OH)2D3. At day 2, in group I and II, before the administration of 1,25(OH)2D3, protein excretion was significantly increased when compared to controls. Overt proteinuria was maintained until day 14 in group I whereas in group II protein excretion was significantly reduced from day 3 to day 14. Moreover, treatment with 1,25(OH)2D3 abrogated podocytes injury, detected as desmin expression and loss of nephrin and zonula occludens-1 (ZO-1), two slit diaphragm-associated proteins, and glomerular polyanion staining, that were observed in group I. In conclusion, these results suggest that 1,25(OH)2D3 administrated with a therapeutic regiment may revert proteinuria, counteracting glomerular podocyte injury.

Ischemia is an inciting factor in 50% of incidences of acute renal failure, and it increases the risk of organ rejection after renal transplantation. We have previously demonstrated that resveratrol (RSV) reduces ischemia-reperfusion (I/R) injury of rat kidney both by antioxidant and anti-inflammatory mechanisms. However, a clear morphological demonstration of this activity has not been made. To answer this question we have performed a new set of experiments following the experimental protocol reported below to investigate the effects of I/R injury and RSV pretreatment on kidney morphology by computerized morphometric analysis. Both renal arteries were clamped for 40 minutes in 40 male Wistar rats (b.w. 220 +/- 20 g); 20 rats were pretreated with RSV 1 microM e.v. 40 minutes before clamping. All animals were reperfused for 24 hours and then sacrificed. Histological examination showed tissue conservation in treated rats. I/R-induced glomerular collapse (as revealed by mean glomerular volume and glomerular shape factor) was significantly reduced by RSV pretreatment. Capillary tuft/Bowman's capsule area ratio was enhanced in the I/R group suggesting tubular hypertension. RSV pre-treatments significantly reduced this parameter to the control value. The number of platelet clots in the capillary tuft and tubular necrosis were also reduced by RSV versus I/R group. L-NAME administration worsened both functional and structural damage. Finally, cGMP urinary levels were markedly reduced from 12.1 +/- 8.4 nmol/day to 0.10 +/- 0.10 nmol/day in the I/R group. RSV provided cGMP (5.01 +/- 1.5 nmol/day, P < 0.05). As expected, L-NAME administration significantly reduced cGMP in urine (0.71 +/- 0.6 nmol/day). The present study confirms the protective effect of RSV pretreatment in I/R injury of rat kidney and suggests multiple mechanisms of action.

Background: Cohort studies have demonstrated an association between C-reactive protein (CRP) and interleukin-6 (IL-6) and all-cause and cardiovascular mortality in end-stage renal disease (ESRD) patients. Interleukin-8 (IL-8) appears to be not only the plasma expression of the acute-phase response but also a direct pathogenetic mediator of the atherosclerotic process. Methods: To evaluate the role of IL-8 in predicting outcome, 76 chronic dialytic patients were prospectively followed for 18 months. At baseline, blood samples were taken for analysis of high-sensitivity CRP, IL-6, IL-8 and other standard laboratory analyses. Results: Median IL-8 was 5.2 mg/l, therefore near half of the patients had IL-8 values within the range of ‘normal limits’. IL-6 and CRP were significantly correlated (r = 0.45, p < 0.001) and a positive correlation was also found between IL-6 and IL-8 (r = 0.39, p < 0.001). The correlation coefficient between IL-6 and CRP was 0.43 (p < 0.001) and 0.50 (p < 0.001) in patients without and with history and/or clinical signs of cardiovascular disease, respectively. After a follow-up of 1.5 years, 8 patients had died from cardiovascular causes and another 7 patients for other reasons; furthermore 9 major nonfatal cardiovascular events were recorded. Stepwise regression analysis showed IL-8 as the strongest independent predictor of all-cause and cardiovascular events (p = 0.0025) even after adjustment for age and dialytic age, followed by IL-6 and CRP (p < 0.01). Conclusion: Despite a small population and a relatively short follow-up period, this study firstly demonstrated that IL-8 is a powerful independent predictive factor for cardiovascular and overall mortality cause in ESRD patients.

No abstract