Tert-Butylhydroquinone pretreatment protects kidney from ischemia-reperfusion injury.

BACKGROUND: It is generally accepted that an excessive production of reactive oxygen species plays an important role in acute renal failure secondary to ischemia and reperfusion. tert-Butylhydroquinone (tBHQ) is a well-known antioxidant. In this study, we evaluated whether tBHQ pretreatment prevented renal damage induced by ischemia and reperfusion (I/R). METHODS: Four groups of rats were studied: (a) control-sham (CT), (b) tBHQ-sham (tBHQ), (c) I/R and (d) tBHQ + I/R. Intraperitoneal (i.p.) injections of tBHQ (50 mg/kg) were given to the tBHQ and tBHQ + I/R groups and 3% ethanol/isotonic saline solution to the CT and I/R groups. Animals were killed 24 hours after I/R. RESULTS: tBHQ attenuated I/R-induced renal dysfunction, structural damage, oxidative/nitrosative stress, glutathione depletion and the decrease in several antioxidant enzymes. CONCLUSION: The renoprotective effect of tBHQ on I/R injury was associated with the attenuation in oxidative/nitrosative stress and the preservation of antioxidant enzymes.

Preventive effect of tert-butylhydroquinone on cisplatin-induced nephrotoxicity in rats.

Cis-diamminedichloroplatinum II (CDDP)-induced nephrotoxicity is associated with the overproduction of reactive oxygen species. tert-Butylhydroquinone (tBHQ) is a compound widely used as food antioxidant. The purpose of this study was to investigate the ability of tBHQ to prevent the nephrotoxic effect of CDDP in rats as well as the mechanisms involved. Thirty-six Wistar rats divided in the following groups were used: control, tBHQ (12.5mg/kg), CDDP (7.5mg/kg) and tBHQ+CDDP. Twenty-four h urine was collected at the beginning and at the end of the experiment and the rats were sacrificed 72h after CDDP-administration. Histological studies were performed and markers of renal function and oxidative/nitrosative stress were measured. In addition, the activity of the following antioxidant enzymes was measured: glutathione peroxidase (GPx), superoxide dismutase (SOD), glutathione reductase (GR) and glutathione-S-transferase (GST). CDDP-induced renal dysfunction, structural damage and oxidative/nitrosative were prevented by tBHQ. In addition, tBHQ completely prevented the CDDP-induced fall in GPx and GST activities. In conclusion, the present study indicates that the antioxidant activity of tBHQ is associated with its nephroprotective effect against CDDP-induced acute kidney injury in rats.

Renoprotection by alpha-Mangostin is related to the attenuation in renal oxidative/nitrosative stress induced by cisplatin nephrotoxicity.

Cisplatin (CDDP) is a chemotherapeutic agent that produces nephrotoxicity associated with oxidative/nitrosative stress. alpha-Mangostin (alpha-M) is a xanthone extracted from mangosteen with antioxidant and anti-inflammatory properties. The purpose of this study was to evaluate the renoprotective effect of alpha-M on the CDDP-induced nephrotoxicity. alpha-M was administered (12.5 mg/kg/day, i.g.) for 10 days (7 days before and 3 days after CDDP injection). On day 7, rats were treated with a single injection of CDDP (7.5 mg/Kg, i.p.); 3 days after the rats were killed. alpha-M attenuated renal dysfunction, structural damage, oxidative/nitrosative stress, decrease in catalase expression and increase in mRNA levels of tumour necrosis factor alpha and transforming growth factor beta. In conclusion the renoprotective effect of alpha-M on CDDP-induced nephrotoxicity was associated with the attenuation in oxidative/nitrosative stress and inflammatory and fibrotic markers and preservation of catalase activity.

Treatment with pyrrolidine dithiocarbamate improves proteinuria, oxidative stress, and glomerular hypertension in overload proteinuria.

We evaluated whether the blockade of the proinflammatory transcription factor NF-kappaB would modify the oxidative stress, inflammation, and structural and hemodynamic alterations found in the kidney as a result of massive proteinuria. Twenty male Sprague-Dawley rats were injected with 2 g of BSA intraperitoneally daily for 2 wk. Ten of them received in addition the inhibitor of NF-kappaB activation pyrrolidine dithiocarbamate (PDTC; 200 mg.kg(-1).day(-1) sc) and the rest received vehicle. Seven rats that received intraperitoneal saline were used as controls. Glomerular hemodynamics were studied after 14 days. Markers of oxidative stress (NF-kappaB subunit p65+ cells, 3-nitrotyrosine, and 4-hydroxynonenal), inflammation (cortical CD68+ cells and NOS-II), and afferent arteriole damage were assessed by immunohistochemistry and morphometry. Activity of antioxidant enzymes superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase was evaluated in renal cortex and medulla. Albumin overload induced massive proteinuria, oxidative stress with reduced activity of antioxidant enzymes, NF-kappaB activation, inflammatory cell infiltration, a significant presence of proteinaceous casts, systemic and glomerular hypertension, as well as arteriolar remodeling. Treatment with PDTC prevented or improved all of these findings. In this model of nephrotic syndrome, we demonstrate a key role for oxidative stress and inflammation in causing systemic and glomerular hypertension and proteinuria. Oxidative stress and inflammation may have a key role in accelerating renal injury associated with intense proteinuria.