Cisplatin induced damage in kidney genomic DNA and nephrotoxicity in male rats: The protective effect of grape seed proanthocyanidin extract

Abstract

The clinical use of cisplatin is highly limited, because of its renal toxicity. In this study, the protective effect of grape seed proanthocyanidin extract (GSPE) against cisplatin-induced nephrotoxicity is investigated in rats. Results showed that DNA qualitative analysis indicated an increase in the instability of the DNA purified from the cisplatin exposed kidney cells. Agarose gel electrophoresis revealed DNA damage in the form of smearing as well as ladder like fragmentation of the kidney genomic DNA. Cisplatin produced different RAPD patterns compared to control. Deletion of bands for the amplified DNA extracted from cisplatin treated rats was the most common outcome. Treatment with cisplatin decreased albumin, and increased urea and creatinine. Cisplatin significantly increased the level of kidney free radicals, and decreased the glutathione content and the activities of the antioxidant enzymes. The presence of GSPE with cisplatin significantly alleviated its nephrotoxicity. In conclusion, the present study showed that cisplatin induced damage in the kidney genomic DNA, lipid peroxidation, inhibition of antioxidant enzymes and alterations of biochemical parameters in plasma and kidney of rats. While, GSPE treatment protected against the toxic effects induced by cisplatin. Thus, GSPE may be used to prevent toxicity during chemotherapeutic treatment with cisplatin.

Introduction

Cisplatin (cis-dichlorodiammineplatinum (II), CDDP) is a synthetic anticancer drug extensively used clinically for the treatment of several human malignancies (Tikoo et al., 2007, Ajith et al., 2007). Although higher doses of cisplatin are more efficacious for the suppression of cancer, high dose therapy manifests irreversible renal dysfunction and cumulative nephrotoxicity (Atessahin et al., 2005, Tikoo et al., 2007). Less toxic platinum compounds have been developed, yet cisplatin remains the drug of choice in platinum based therapy regimens, and one of the most commonly used chemotherapeutic drugs (Hanigen and Devarajan, 2003). In spite of prophylactic intensive hydration and forced diuresis, irreversible renal damage occurs in about one third of cisplatin-treated patients (Ali and Al-Moundhri, 2006, Razzaque, 2007). Thus, prevention of the side effects of cisplatin is one of the major issues in treating cancer patients (Chang et al., 2002). Recent studies are directed more towards reducing the cytotoxic impact of cisplatin and several strategies have been explored to reduce the side effects of cisplatin therapy (Hanigen and Devarajan, 2003, Ali and Al-Moundhri, 2006). Amifostine – a thiophosphate prodrug – is an antioxidant approved by the FDA for the prevention of toxicities clinically associated with cisplatin (Razzaque, 2007).

Cisplatin nephrotoxicity can occur either acutely, or after repeated administration. The kidney selectively accumulates cisplatin through mediated transport more than the other organs (Hanigen and Devarajan, 2003). The exact mechanism of CDDP-induced nephrotoxicity is still not fully understood (Sato et al., 2005, Badary et al., 2005, Ali and Al-Moundhri, 2006). Formation of free radicals, leading to oxidative stress, has been suggested as one of the pathogenic mechanisms of CDDP-induced nephrotoxicity (Atessahin et al., 2005, Ajith et al., 2007). Cisplatin causes the generation of reactive oxygen species (ROS), such as superoxide anion and hydroxyl radical and consequently, depletes glutathione (GSH) and inhibits the activity of antioxidant enzymes in renal tissues (Badary et al., 2005, Ajith et al., 2007). Various data indicates that CDDP induces oxidative stress, lipid peroxidation and DNA damage (De martinis and Bianchi, 2001, Chang et al., 2002, Badary et al., 2005). Some antioxidants have been tested for their ability to protect against CDDP-induced nephrotoxicity in experimental animals (Hanigen and Devarajan, 2003, Ali and Al-Moundhri, 2006, Ajith et al., 2007).

Proanthocyanidins are naturally occurring polyphenolic compounds widely available in fruits, vegetables, nuts, seeds, flowers and bark. Grape seed proanthocyanidins (GSPE), a combination of biologically active bioflavonoids including oligomeric proanthocyanidins, have been shown to exert a novel spectrum of biological, therapeutic, and chemopreventive properties (Bagchi et al., 2002, Fine, 2000). GSPE has been shown to serve as one of the most potent free radical scavengers and antioxidants both in vitro and in vivo. Oligomeric proanthocyanidins was provided to be highly bioavailable and provide significantly greater protection against damage of oxidative stress than vitamins C, E and β-carotene (Bagchi et al., 1997, Zhang et al., 2005). Proanthocyanidins have been reported to exert antibacterial, antiviral, anticarcinogenic, antimutagenic, antinflammatory, anti-allergic, and vasodilatory actions (Fine, 2000). Proanthocyanidins have also been shown to inhibit lipid peroxidation, platelet aggregation, capillary permeability and fragility, and to affect enzyme systems including phospholipase A2, cyclooxygenase, and lipoxygenase. Furthermore, proanthocyanidins was proved to have the ability to inhibit the activity of xanthine oxidase, a major generator of free radicals. They can also chelate free iron molecules, and inhibit iron-induced lipid peroxidation (Fine, 2000). It is postulated that in addition to its selective cytotoxicity towards cancer cells, GSPE may up-regulate the bcl-Xs gene as a death promoter and down-regulate the bcl-Xl gene as a death inhibitor in the cancer cells, but not in regular cells (Bagchi et al., 2002, Zhang et al., 2005). A large number of reports demonstrated that oligomeric proanthocyanidins (OPCs) could enhance both the activity of chemotherapeutic agents and diminish their normal tissue toxicity (Yamakoshi et al., 2002, Zhang et al., 2005). Therefore, the aim of this study was to evaluate the level of oxidative stress in CDDP mediated nephrotoxicity and to investigate the possible protective effect of GSPE on the CDDP-induced changes in biochemical and genomic levels of rats.