Protective effects of L-arginine against cisplatin-induced renal oxidative stress and toxicity: role of nitric oxide

Nephrotoxicity is a dose-limiting factor in clinical use of cisplatin. The changes in renal haemodynamics were suggested to play a role in cisplatin-induced nephrotoxicity. The aim of the present study was to investigate the effect of modulation of nitric oxide on the severity of cisplatin-induced nephrotoxicity using an experimental rat model. A nitric oxide precursor, L-arginine and an inhibitor of nitric oxide synthase, L-NAME were used. After six days of cisplatin injection, acute nephrotoxicity was demonstrated by a marked increase in serum creatinine and blood urea nitrogen. Histological examination of the kidneys confirmed the occurrence of renal damage. Moreover, cisplatin induced an increase in the level of lipid peroxides and oxidized glutathione and a depletion of reduced glutathione. The activities of the antioxidant enzymes glutathione peroxidase and superoxide dismutase were also lowered. Besides, there was a reduction in the kidney total nitrate/nitrite levels. L-arginine significantly attenuated the oxidative stress and nephrotoxic effect of cisplatin. On the other hand, L-NAME was found to aggravate cisplatin nephrotoxicity. In conclusion, the decrease in the kidney nitric oxide level contributes, at least in part, in the mechanism underlying the nephrotoxicity of cisplatin. Furthermore, L-arginine shows nephroprotective effects and might be useful in improving the therapeutic index of cisplatin.     

Nrf2/HO-1 signaling pathway may be the prime target for chemoprevention of cisplatin-induced nephrotoxicity by lycopene

Cisplatin is used against various types of solid tumors. However, its use is limited by its nephrotoxicity, with about 25–35% patients experiencing a significant decline in renal function after a single dose of cisplatin. This study reports that lycopene mitigates the nephrotoxic effect of cisplatin in rat through Nrf2-mediated induction of heme oxygenase-1 (HO-1). Eight weeks old male rats (200–215 g) were supplemented with lycopene complex containing 6% lycopene, 1.5% tocopherols, 1% phytoene and phytofluene, and 0.2% β-carotene for 10 days at a dose level of 6 mg/kg bw, followed by a single i.p. injection of cisplatin (7 mg/kg bw). Western blot analysis of renal Nrf2, HO-1 and NF-κB p65 showed that cisplatin-induced decrease in the levels of Nrf-2 and HO-1 was counteracted by lycopene. On the other hand, cisplatin mediated increase in NF-κB p65 was brought down by lycopene. Lycopene supplementation is reported to significantly improve the changes associated with cisplatin nephrotoxicity, as also evident by increased level of antioxidant enzymes. The study suggests that Nrf2/HO-1 signaling pathway may be the prime target for chemoprevention of cisplatin-induced nephrotoxicity by lycopene, and reduces inflammation by inhibiting NF-κB. Correlation between NF-κB and Nrf2 is discussed.     

Protective effect of carnosine against cisplatin-induced nephrotoxicity in mice

The nephroprotective effect of the natural antioxidant carnosine was evaluated in mice with cisplatin-induced acute renal damage, in which generation of reactive oxygen species plays a major role. Nephrotoxicity was induced by a single i.p. injection of cisplatin (20 mg/kg). Carnosine was administered for six consecutive days in a dose of 10 mg/kg/day, i.p., starting 3 days before cisplatin injection. The results revealed that carnosine treatment significantly reduced blood urea nitrogen and serum creatinine levels elevated by cisplatin administration. Also, carnosine significantly attenuated cisplatin-induced increase in malondialdehyde and decrease in reduced glutathione, and catalase and superoxide dismutase activities in renal cortical homogenates. Additionally, histopathological examination and scoring showed that carnosine markedly ameliorated cisplatin-induced renal tubular necrosis. In conclusion, carnosine can be considered a feasible candidate to protect against nephrotoxicity commonly encountered with cisplatin treatment.     

Natural products: potential treatments for cisplatin-induced nephrotoxicity

Cisplatin is a clinically advanced and highly effective anticancer drug used in the treatment of a wide variety of malignancies, such as head and neck, lung, testis, ovary, breast cancer, etc. However, it has only a limited use in clinical practice due to its severe adverse effects, particularly nephrotoxicity; 20%–35% of patients develop acute kidney injury (AKI) after cisplatin administration. The nephrotoxic effect of cisplatin is cumulative and dose dependent and often necessitates dose reduction or withdrawal. Recurrent episodes of AKI result in impaired renal tubular function and acute renal failure, chronic kidney disease, uremia, and hypertensive nephropathy. The pathophysiology of cisplatin-induced AKI involves proximal tubular injury, apoptosis, oxidative stress, inflammation, and vascular injury in the kidneys. At present, there are no effective drugs or methods for cisplatin-induced kidney injury. Recent in vitro and in vivo studies show that numerous natural products (flavonoids, saponins, alkaloids, polysaccharide, phenylpropanoids, etc.) have specific antioxidant, anti-inflammatory, and anti-apoptotic properties that regulate the pathways associated with cisplatin-induced kidney damage. In this review we describe the molecular mechanisms of cisplatin-induced nephrotoxicity and summarize recent findings in the field of natural products that undermine these mechanisms to protect against cisplatin-induced kidney damage and provide potential strategies for AKI treatment.     

Serum thymic factor, FTS, attenuates cisplatin nephrotoxicity by suppressing cisplatin-induced ERK activation

Serum thymic factor (FTS), a thymic peptide hormone, has been reported to attenuate the bleomycin-induced pulmonary injury and also experimental pancreatitis and diabetes. In the present study, we investigated the effect of FTS on cis-diamminedichloroplatinum II (cisplatin)-induced nephrotoxicity. We have already demonstrated that cephaloridine, a nephrotoxic antibiotic, leads to extracellular signal-regulated protein kinase (ERK) activation in the rat kidney, which probably contributes to cephaloridine-induced renal dysfunction. The aim of this study was to examine the effect of cisplatin on ERK activation in the rat kidney and also the effect of FTS on cisplatin-induced nephrotoxicity in rats. In vitro treatment of LLC-PK1 cells with FTS significantly ameliorated cisplatin-induced cell injury. Treatment of rats with intravenous cisplatin for 3 days markedly induced renal dysfunction and increased platinum contents in the kidney cortex. An increase in pERK was detected in the nuclear fraction prepared from the rat kidney cortex from days 1 to 3 after injection of cisplatin. FTS suppressed cisplatin-induced renal dysfunction and ERK activation in the kidney. FTS did not influence any Pt contents in the kidney after cisplatin administration. FTS has been shown to enhance the in vivo expression of heat shock protein (HSP) 70 in the kidney cortex. The beneficial role of FTS against cisplatin nephrotoxicity may be mediated in part by HSP70, as suggested by its up-regulation in the kidney cortex treated with FTS alone. Our results suggest that FTS participates in protection from cisplatin-induced nephrotoxicity by suppressing ERK activation caused by cisplatin.     

Protective effect of concomitant administration of imatinib on cisplatin-induced nephrotoxicity focusing on renal organic cation transporter OCT2

Although the organic cation transporter 2 (OCT2/SLC22A2) mediate renal tubular uptake of cisplatin from the circulation, neither apical multidrug and extrusion (MATE) 1 or MATE2-K mediate tubular secretion of the agent. Therefore, the highly concentrated tubular cisplatin potentiates nephrotoxicity, and these are considered to be a critical mechanism for cisplatin-induced nephrotoxicity. In the present study, we examined the protective effect of imatinib, a cationic anticancer agent, on that nephrotoxicity. Imatinib markedly reduced cisplatin-induced cytotoxicity and platinum accumulation in OCT2-expressing HEK293 cells, but almost no change was found in the cells expressing human MATE1, MATE2-K and rat MATE1. In rats, the renal accumulation of platinum and subsequent nephrotoxicity, based on the blood urea nitrogen, plasma creatinine and creatinine clearance, were significantly decreased with the oral administration of imatinib. The orally administered imatinib significantly increased the area under the plasma concentration-time curve of intravenously administered cisplatin for 3 min by an average of 120%. In additional, the concomitant administration of imatinib clearly avoided the severe renal impairment by the histological examination. In conclusion, the concomitant administration of imatinib with cisplatin prevents cisplatin-induced nephrotoxicity inhibiting the OCT2-mediated renal accumulation of cisplatin.     

Rutin attenuates cisplatin induced renal inflammation and apoptosis by reducing NFκB, TNF-α and caspase-3 expression in wistar rats

Cisplatin is an effective chemotherapeutic agent that displays dose-limiting nephrotoxicity. In the present study the wistar rats were subjected to concurrent prophylactic oral treatment of rutin (75 and 150 mg/kg b.wt.) against the nephrotoxicity induced by intraperitoneal administration of cisplatin (7 mg/kg b.wt.). Efficacy of rutin against the nephrotoxicity was evaluated in terms of biochemical estimation of antioxidant enzyme activities, histopathological changes and expression levels of molecular markers of inflammation and apoptosis. Rutin pretreatment prevented deteriorative effects induced by cisplatin through a protective mechanism that involved reduction of increased oxidative stress as well as caspase-3, TNF-α and NFκB protein expression levels. We found that the beneficial effect of rutin pretreatment is mediated partially by its inhibitory effect on NFκB and TNF-α pathway mediated inflammation, caspase-3 mediated-tubular cell apoptosis, as well as by restoration of histopathological changes against cisplatin administration.     

Regulation of renal organic anion and cation transporters by thymoquinone in cisplatin induced kidney injury

In previous studies, we have demonstrated the biological activity of thymoquinone (TQ), an active compound extracted from the Nigella sativa plant, against cisplatin-induced neurotoxicity. Recenty, it was observed that there is an inherent lack in regulation of renal organic anion and cation transporters in cisplatin-induced nephrotoxicity. Here, we report, for the first time, the effect of TQ on alterations in the renal expression of organic anion transporters (OATs) and organic cation transporters (OCTs), as well as multidrug resistance-associated proteins (MRPs) in rats treated with cisplatin. Twenty-eight 8-week-old male Wistar rats were divided into four groups of control, TQ treated (10 mg/kg b.w. in drinking water for 5 days), cisplatin (7 mg/kg b.w., i.p.) and TQ and cisplatin combination treatment. Cisplatin-induced malondialdehyde (MDA) and 8-isoprostane increase was found to be markedly reduced in rats treated with TQ. In cisplatin only treated rats, the induced renal injury increased protein levels of the efflux transporters MRP2 and MRP4 while expression of OAT1, OAT3, OCT1 and OCT2 was reduced. In combination TQ- and cisplatin-treated rats, expression of MRP2 and MRP4 proteins was decreased in the kidneys. Conversely, TQ treatment increased levels of OCT1, OCT2, OAT1 and OAT3 and decreased levels of 8-isoprostane and MDA levels in cisplatin-treated rats. In conclusion, the present study shows that the TQ synergizes with its nephroprotective effect against cisplatin-induced acute kidney injury in rats.     

Protective role of phosphatidylcholine against cisplatin-induced renal toxicity and oxidative stress in rats

Although cisplatin is widely used in the treatment of cancers, clinical use of cisplatin is limited due to its nephrotoxicity. Pathophysiological mechanism of cisplatin-induced renal toxicity is a complex process and has not been fully understand. Reactive oxygen species (ROS) and oxidative stress have been presumed to be involved in this damage process. Phosphatidylcholine (PC) has antioxidant effect and prevents oxidative stress. Therefore, the present study aimed to investigate potential protective effects of PC on cisplatin-induced renal damage in rat. We examined the protective effects of PC on cisplatin-induced renal damage by assessment of serum creatinine, BUN, lipid peroxidation, total glutathione, glutathione peroxidase activity, catalase activity, superoxide dismutase activity and histophathological changes. PC ameliorated cisplatin-induced increases in serum creatinine, urea and oxidative stress. PC also decreased tubular degeneration and hypertrophy of glomeruli. PC may have a protective effect against cisplatin-induced nephrotoxicity in rats via enhancing antioxidant enzyme activity.     

Protective effects of apocynin against cisplatin-induced oxidative stress and nephrotoxicity

Cis-diamminedichloroplatinum (II) (cisplatin) is an effective chemotherapeutic agent successfully used in the treatment of a wide range of tumors; however, nephrotoxicity has restricted its clinical use. Several studies have shown that reactive oxygen species are involved in cisplatin-induced nephrotoxicity, including hydrogen peroxide, hydroxyl radical and superoxide anion (O(2)(-)). The source of O(2)(-) in cisplatin-induced renal damage has not been established. The aim of this study was to investigate if NADPH oxidase is involved in cisplatin-induced nephrotoxicity using apocynin, a widely used NADPH oxidase inhibitor. Rats were studied 3 days after a single injection of cisplatin (7.5mg/kg, i.p.). Apocynin was given in the drinking water (2g/L) 7 days before and 3 days after cisplatin injection. Apocynin treatment was able to ameliorate the renal histological damage and the increase in blood urea nitrogen, serum creatinine, and urinary excretion of total protein, N-acetyl-beta-d-glucosaminidase and glutathione-S-transferase induced by cisplatin. In addition, the protective effect of apocynin was associated with the amelioration of cisplatin-induced oxidative and nitrosative stress. Our data suggest that O(2)(-) derived from NADPH oxidase triggers some of the side effects due to cisplatin administration.     

Zingiber officinale Roscoe alone and in combination with alpha-tocopherol protect the kidney against cisplatin-induced acute renal failure.

Oxidative stress due to abnormal production of reactive oxygen molecules (ROM) is believed to be involved in the etiology of toxicities of many xenobiotics. Evidences suggested that ROM is involved in the nephrotoxicity of a widely used synthetic anticancer drug cisplatin. The nephroprotective effects of ethanol extract of Zingiber officinale alone and in combination with vitamin E (alpha-tocopherol) were evaluated using cisplatin (single dose of 10 mg/kg body wt, i.p) induced acute renal damage in mice. The results of the study indicated that Z. officinale significantly and dose dependently protected the nephrotoxicity induced by cisplatin. The serum urea and creatinine levels in the cisplatin alone treated group were significantly elevated (P<0.01) with respect to normal group of animals. The levels were reduced in the Z. officinale (250 and 500 mg/kg, p.o) plus cisplatin, vitamin E (250 mg/kg) plus cisplatin, and Z. officinale (250 mg/kg) with vitamin E plus vitamin E treated groups. The renal antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) activities and level of reduced glutathione (GSH) were declined; level of malondialdehyde (MDA) was elevated in the cisplatin alone treated group. The activities of SOD, CAT GPx and level of GSH were elevated and level of MDA declined significantly (P<0.05) in the Z. officinale (250 and 500 mg/kg) plus cisplatin and Z. officinale (250 mg/kg) with vitamin E plus cisplatin treated groups. The protective effect of Z. officinale (250 mg/kg body wt) was found to be better than that of vitamin E (250 mg/kg body wt). The results also demonstrated that combination of Z. officinale (250 mg/kg) with vitamin E (250 mg/kg) showed a better protection compared to their 250 mg/kg alone treated groups. This study concluded that ethanol extract of Z. officinale alone and in combination with vitamin E partially ameliorated cisplatin-induced nephrotoxicity. This protection is mediated either by preventing the cisplatin-induced decline of renal antioxidant defense system or by their direct free radical scavenging activity.     

An Extract of Rhodobacter sphaeroides Reduces Cisplatin-Induced Nephrotoxicity in Mice

Cisplatin is used as a treatment for various types of solid tumors. Renal injury severely limits the use of cisplatin. Renal cell apoptosis, oxidative stress, and inflammation contribute to cisplatin-induced nephrotoxicity. Previously, we found that an extract of Rhodobacter sphaeroides (Lycogen™) inhibited proinflammatory cytokines and the production of nitric oxide in activated macrophages in a dextran sodium sulfate (DSS)-induced colitis model. Here, we evaluated the effect of Lycogen™, a potent anti-inflammatory agent, in mice with cisplatin-induced renal injury. We found that attenuated renal injury correlated with decreased apoptosis due to a reduction in caspase-3 expression in renal cells. Oral administration of Lycogen™ significantly reduced the expression of tumor necrosis factor-α and interleukin-1β in mice with renal injury. Lycogen™ reduces renal dysfunction in mice with cisplatin-induced renal injury. The protective effects of the treatment included blockage of the cisplatin-induced elevation in serum urea nitrogen and creatinine. Meanwhile, Lycogen™ attenuated body weight loss and significantly prolonged the survival of mice with renal injury. We propose that Lycogen™ exerts anti-inflammatory activities that represent a promising strategy for the treatment of cisplatin-induced renal injury.     

Proteasome inhibitors prevent cisplatin-induced mitochondrial release of apoptosis-inducing factor and markedly ameliorate cisplatin nephrotoxicity

We demonstrate the effect of proteasome inhibitors in mitochondrial release of apoptosis-inducing factor (AIF) in cisplatin-exposed renal tubular epithelial cells (LLC-PK₁ cells) and in a model of cisplatin nephrotoxicity. Immunofluorescence and subcellular fractionation studies revealed cisplatin-induced translocation of AIF from the mitochondria to nucleus. Mcl-1, a pro-survival member of the Bcl-2 family, is rapidly eliminated on exposure of renal cells to cisplatin. Proteasome inhibitors PS-341 and MG-132 blocked cisplatin-induced Mcl-1 depletion and markedly prevented mitochondrial release of AIF. PS-341 and MG132 also blocked cisplatin-induced activation of executioner caspases and apoptosis. These studies suggest that proteasome inhibitors prevent cisplatin-induced caspase-dependent and -independent pathways. Overexpression of Mcl-1 was effective in blocking cisplatin-induced cytochrome c and AIF release from the mitochondria. Downregulation of Mcl-1 by small interfering RNA promoted Bax activation and cytochrome c and AIF release, suggesting that cisplatin-induced Mcl-1 depletion and associated Bax activation are involved in the release of AIF. Expression of AIF protein in the mouse was highest in the kidney compared to the heart, brain, intestine, liver, lung, muscle, and spleen. In an in vivo model of cisplatin nephrotoxicity, proteasome inhibitor MG-132 prevented mitochondrial release of AIF and markedly attenuated acute kidney injury as assessed by renal function and histology. These studies provide evidence for the first time that the proteasome inhibitors prevent cisplatin-induced mitochondrial release of AIF, provide cellular protection, and markedly ameliorate cisplatin-induced acute kidney injury. Thus, AIF is an important therapeutic target in cisplatin nephrotoxicity and cisplatin-induced depletion of Mcl-1 is an important pathway involved in AIF release.     

A possible cellular mechanism of cisplatin-induced nephrotoxicity

Cisplatin, a relatively new antitumor agent, is associated with renal function impairment. The mechanism of cisplatin-induced nephrotoxicity is unknown. A mouse model was used to examine nephrotoxicity induced by cisplatin. This study demonstrates both morphologically and biochemically that mitochondrial damage may be associated with cisplatin-induced cellular toxicity. The morphological changes are evident after 72 h following a single 10 mg/kg i.p. dose of cisplatin. Biochemical changes also follow the morphological abbreviations. In vitro incubation of cisplatin with cells also shows a decline in Rhodamine 123 fluorescence with time, which is indicative of mitochondrial damage. The present findings suggest the possibility that the nephrotoxic effects of cisplatin may be related to a mitochondrial damage.     

Nephroprotective effect of Bauhinia variegata (Linn.) whole stem extract against cisplatin-induced nephropathy in rats

The nephroprotective activity of the ethanolic extract of Bauhinia variegata (Linn.) whole stem against cisplatin-induced nephropathy was investigated by an in vivo method in rats. Acute nephrotoxicity was induced by i.p. injection of cisplatin (7 mg/kg of body weight (b.w.)). Administration of ethanol extract at dose levels of 400 and 200 mg/kg (b.w.) to cisplatin-intoxicated rats for 14 days attenuated the biochemical and histological signs of nephrotoxicity of cisplatin in a dose-dependent fashion. Ethanol extract at 400 mg/kg decreased the serum level of creatinine (0.65 ± 0.09; P<0.001) and urea (32.86 ± 5.88; P<0.001) associated with a significant increase in body weight (7.16 ± 1.10; P<0.001) and urine volume output (11.95 ± 0.79; P<0.05) as compared to the toxic control group. The ethanol extract of B. variegata at 400 mg/kg (b.w.) exhibited significant and comparable nephroprotective potential to that of the standard polyherbal drug cystone. The statistically (one-way-ANOVA followed by Tukey-Kramer multiple comparison) processed results suggested the protective action of B. variegate whole stem against cisplatin-induced nephropathy.     

Susceptibility loci involved in cisplatin-induced cytotoxicity and apoptosis

OBJECTIVES: Cisplatin is a widely used chemotherapeutic agent; however, nephrotoxicity and neuropathy are obstacles for drug efficacy. Little is known about the genes or genetic variants contributing to the risk of developing these toxicities or chemotherapeutic response. Thus, we have applied a cell-based model to identify and characterize previously unknown genes that may be involved in cellular susceptibility to cisplatin. METHODS: Lymphoblastoid cell lines from 27 large Centre d'Etude du Polymorphisme Humain pedigrees were used to elucidate the genetic contribution to cisplatin-induced cytotoxicity. Phenotype was defined as cell growth inhibition following exposure of cell lines to increasing concentrations of cisplatin for 48 h. RESULTS: Significant heritability, ranging from 0.32 to 0.43 (P<10), was found for the cytotoxic effects of each concentration (1, 2.5, 5, 10, and 20 micromol/l) and IC50, the concentration required for 50% cell growth inhibition. Linkage analysis revealed 11 genomic regions on six chromosomes with logarithm of odds (LOD) scores above 1.5 for cytotoxic phenotypes. The highest LOD score was found on chromosome 4q21.3-q35.2 (LOD=2.65, P=2.4x10(-4)) for 5 micromol/l cisplatin. Quantitative transmission disequilibrium tests were performed using 191973 nonredundant single nucleotide polymorphisms (SNPs) located in the 1 LOD confidence interval of these 11 regions. Twenty SNPs, with 10 SNPs located in five genes, were significantly associated with cisplatin-induced cytotoxicity (P相似文献   

Concomitant lansoprazole ameliorates cisplatin-induced nephrotoxicity by inhibiting renal organic cation transporter 2 in rats

Cisplatin is used widely for the treatment of multiple solid tumors. Cisplatin-induced nephrotoxicity is caused by renal accumulation of cisplatin via human organic cation transporter 2 (hOCT2). As lansoprazole, a proton pump inhibitor, is known to inhibit hOCT2 activity, lansoprazole might ameliorate cisplatin-induced nephrotoxicity. A previous study showed that concomitant lansoprazole administration ameliorated nephrotoxicity in patients receiving cisplatin. However, the detailed mechanism remains to be clarified. In the present study, the drug–drug interaction between lansoprazole and cisplatin was examined using hOCT2-expressing cultured cells and rat renal slices. Moreover, the effect of lansoprazole on cisplatin-induced nephrotoxicity and the pharmacokinetics of cisplatin in rats was investigated. In the uptake study, lansoprazole potently inhibited the uptake of cisplatin in hOCT2-expressing cultured cells and rat renal slices. The in vivo rat study showed that concomitant lansoprazole significantly ameliorated cisplatin-induced nephrotoxicity and reduced the renal accumulation of platinum up to approximately 60% of cisplatin alone at 72 h after cisplatin intraperitoneal administration. Furthermore, the renal uptake of platinum at 3 min after intravenous cisplatin administration in rats with cisplatin and lansoprazole decreased to 78% of rats with cisplatin alone. In addition, there was no significant difference in the plasma platinum concentration between rats treated with and without lansoprazole at 3 min after cisplatin intravenous administration. These findings suggested that concomitant lansoprazole ameliorated cisplatin-induced nephrotoxicity by inhibiting rOCT2-mediated cisplatin uptake in rats, thus decreasing cisplatin accumulation in the kidney. The present findings provided important information for the establishment of novel protective approaches to minimize cisplatin-induced nephrotoxicity.     

Hyperbilirubinemia's protective effect against cisplatin nephrotoxicity in the Gunn rat

Gunn rats, deficient in the enzyme uridine diphosphate glucuronyl transferase, were used to investigate the effects of unconjugated hyperbilirubinemia in cisplatin nephrotoxicity. The effect of bilirubin on the antineoplastic activity of cisplatin in osteosarcoma cell lines was also determined. The in vivo model involved three groups of rats (n=6 rats/group): homozygous Gunn rats (j/j), heterozygous Gunn rats (j/+), and congenic Wistar rats. On day 0, all rats were given 4 mg/kg cisplatin intraperitoneally. Blood was sampled on days 0, 3, and 5 for bilirubin, BUN, and creatinine and kidneys were taken on day 5. Cell culture was performed in four canine osteosarcoma cell lines using the average concentrations of bilirubin for homozygous Gunn rats at day 0 and 3. Bilirubin was added to cell lines alone and with cisplatin. Cell viability was assessed using the CellTiter Blue assay. Serum bilirubin levels were highly elevated in Gunn j/j, moderately elevated in Gunn j/+, and undetectable in Wistar rats at day 0. Bilirubin provided a nephroprotective effect, with significantly lower BUN and creatinine in Gunn j/j when compared with Wistar rats at day 5. Histological grading demonstrated preservation of the S3 segment in Gunn j/j when compared with Wistar rats (P<0.05). Bilirubin had no significant effect on the antineoplastic effect of cisplatin at either concentration in the four cell lines (P<0.001). Hyperbilirubinemia in the Gunn rat provided marked preservation of renal function and histology in a cisplatin nephrotoxicity model. Exogenous bilirubin did not interfere with the antineoplastic activity of cisplatin in vitro.     

Effects of lycopene against cisplatin-induced nephrotoxicity and oxidative stress in rats

The aim of this study was to investigate the effects of lycopene on cisplatin-induced nephrotoxicity and oxidative stress in rats. Adult male Sprague-Dawley rats were randomly divided into four groups. The control group (group 1) received physiological saline; animals in group 2 received only cisplatin; a 10 days of lycopene pre-treatment was applied to the animals in group 3 before administration of cisplatin; a 5 days of lycopene treatment was performed following administration of cisplatin for the animals in group 4. Cisplatin (7 mg/kg) was intraperitoneally injected as a single dose and lycopene (4 mg/kg) was administered by gavage in corn oil. Biochemical and histopathological methods were utilised for evaluation of the nephrotoxicity. The concentrations of creatinine, urea, Na+ and K+ in plasma and levels of malondialdehyde and reduced glutathione as well as glutathione peroxidase and catalase activities were determined in kidney tissue. Administration of cisplatin to rats induced a marked renal failure, characterized with a significant increase in plasma creatinine and urea concentrations. Na+ and K+ levels of rats received cisplatin alone were not significantly different compared to control group, but they had higher kidney malondialdehyde, and lower reduce glutathione concentrations, glutathione peroxidase and catalase activities. Lycopene administration produced amelioration in biochemical indices of nephrotoxicity in both plasma and kidney tissues when compared to group 2; pre-treatment with lycopene being more effective. Results from this study indicate that the novel natural antioxidant lycopene might have protective effect against cisplatin-induced nephrotoxicity and oxidative stress in rat.