Therapeutic effects of oleuropein on cisplatin-induced pancreas injury in rats

Aims: Cisplatin (CIS) is an influential chemotherapeutic agent in the treatment of several types of malignant solid tumors, but its clinical use is related with ototoxicity. Oleuropein (OLE) is a natural antioxidant and scavenging free radicals. Here, we first explore the efficacy of OLE in pancreas against to the toxicity of CIS and also analyses its mechanism. Materials and Methods: Fifty-six Sprague-Dawley rats were equally divided into eight groups, including, control group which received 7 mg/kg/day CIS intraperitoneally (i.p.) for 24 h, groups treated with doses of 50, 100, and 200 mg/kg OLE i.p. for 3 days, and groups which received same dose of CIS with three doses of OLE. After the treatments, animals were sacrificed. The oxidative DNA damage (8-hydroxy-2' -deoxyguanosine [8-OHdG]), total oxidative stress (TOS), total antioxidant status (TAS), and malondialdehyde (MDA) levels were evaluated in the pancreas. The histopathology of the pancreas was examined using three different staining methods: hematoxylin-eosin, periodic acid-Schiff, and alcian blue. Serum was provided to assess pancreatic function the lipase and amylase values. Results: The results showed that CIS significantly increased the level of TOS, MDA, and 8-OHdG in tissue as compared to the control group. Moreover, severe tissue damages were detected in the pancreas. Whereas, OLE at high dose significantly decreased the formations of 8-OHdG, the level of MDA, and increased levels of TAS in tissue samples. In the CIS group, the levels of amylase and lipase increased compared with the control group. However, there were statistically significant differences among the CIS group and the CIS + OLE groups in the values of both amylase and lipase. In addition, histopathological findings observed in CIS group in the pancreatic tissue alleviated in CIS + OLE groups. Conclusion: We hope that the results of this study will provide an impetus for future investigations of novel treatment strategies for OLE in pancreas due to CIS.