Ameliorative Effects of Watermelon and Aloe vera against Cadmium Damage on the Histomorphology of the Heart Tissue of Adult Wistar Rats (Rattus novergicus)

Cadmium (Cd) is a toxic element that can produce reactive oxygen species. Fruits and vegetables are natural sources of various bioactive compounds. Watermelon contains nutritional agents like lycopene, citrulline and arginine and Aloe vera is used for therapeutic purposes. This study was carried out to investigate the antioxidant property of watermelon and Aloe vera against cadmium damaging effect on the heart tissues using Haematoxylin and Eosin (H/E) stain. Thirty five (35) Wistar rats were obtained and acclimatized for two weeks. They were divided into seven (7) groups, five (5) rats each. Group 1 normal control received 3 mg/kg/bw of phosphate buffer (pH 7.4) intraperitoneally. Group 2, received 3 mg/kg/bw of Cd (3CdSO4.8H2O) intraperitoneally. Group 3 (therapeutic control) received 100 mg/kg/bw of vitamin C and 300 mg/kg/bw of vitamin E orally once daily. Group 4 (therapeutic control and induced) received same as group 3 with Cd induction intraperitoneally two days before sacrifice. Group 5, 6 and 7 treatment groups were induced with 3 mg/kg/bw of Cd intraperitoneally before treatment with 80 mg/kg/bw of watermelon, 80 mg/kg/bw of Aloe vera and 40 mg/kg/bw of both extract orally and twice daily respectively. The experiment lasted for 4 weeks. The histomorphological result obtained showed normal cardiac features in group 1, damage in myofibril, displaced nuclei in group 2, displaced striation in group 5 and 6 but, improvement was observed as compared to group 2 rats, little displacement of nuclei in group 4, normal morphology in groups 3 and 7 animals were evident. The result from this experiment demonstrated the high degree of potency in the action of Aloe vera and watermelon combined in preventing oxidative tissues damage to the heart due to cadmium interaction.