Toxicological Profile of Anacardium occidentale Nut Shell Extract on Hematologic and Antioxidant Parameters in Brain and Testicular Tissues of Wistar Rats

The nut shell liquid of Cashew (Anacardium occidentale) has been reported to contain several compounds. The nut shell liquid possesses insecticidal activity in addition to several biological activities. Based on the report of insecticidal activity of Cashew nut shell liquid, the present study investigates the possible toxicological effects of Cashew nut shell extract (CNSE) in brain and testes of experimental rats. Cashew nut shell extract was administered to rats. The study used Forty-five male Wistar rats (average weight of 120g), being divided into nine groups (5 rats each), and given oral gavage as Groups A (corn oil), B (50 mg/kg), C (100 mg/kg), D (150 mg/kg), E (200 mg/kg), F (250 mg/kg), G (300 mg/kg), H (350 mg/kg) and I (400 mg/kg CNSE).Cashew nut shell was subjected to Soxhlet extraction using n-hexane, and then concentrated by a Rotary evaporator to obtain Cashew nut shell extract (CNSE). After 28 days, the rats were fasted overnight and subjected to anesthesia. Blood was collected by cardiac puncture for determinations of White blood cell (WBC), granulocytes and platelets. Brain and testes were harvested, rinsed and processed to obtain homogenates for determinations of Thiobarbituric acid-reacting substances (TBARS), superoxide dismutase (SOD), catalase, Glutathione-S-transferase (GST) and glutathione-S-transferase (GPx). Brain and testicular tissues were subjected to histological examination under light microscopy. The CNSE significantly reduced Total WBCs count, while platelets and granulocytes were increased compared with controls. The CNSE reduced catalase activities in brain and testes, while SOD was reduced in brain, but increased in testes. The GST activities in brain and testes were not significantly affected. However, GPx activity was increased in brain, but reduced in testes relative to controls. High doses of CNSE (250 - 400 mg/kg) showed neuronal changes in brain, while distortions were found in the interstitial space, seminiferous tubules and sertoli cells of testicular tissue. The findings from this study have suggested that Cashew nut shell extract may not cause hematological toxicity, but could potentially induce oxidative injury in both brain and testes of experimental rat models.