Protective effect of pomegranate peel extract on diabetic ocular structural changes in experimental diabetic rats: A histological, immunohistochemical and clinical study

Abstract

Ocular complications of diabetes mellitus are rapidly progressing and have become a leading cause of vision impairment. The present study evaluated the potential protective role of pomegranate peel extract, as a powerful antioxidant agent, on the ocular complications of diabetes. One hundred, 8 weeks old, male Wistar rats were subdivided into three groups; the first control group (non-diabetic) was injected intraperitoneally with a single dose (2 ml/animal) of citrate buffer alone. The second group (diabetic untreated) was subjected to induction of diabetes by an intraperitoneal single dose of streptozotocin (60 mg/kg body weight). The third group (diabetic treated) was subjected to induction of diabetes as the second group and given simultaneously, 500 mg/kg body weight of pomegranate peel extract orally once per day with the drinking water. Clinical examination of lens and fundus was made, and the biochemical analysis was done at 8, 12, 16, 20, 24, 28, 32, 36 and 40 weeks after diabetes induction. At the end of the investigation (40 weeks), the rats were anesthetized, and the eyeballs were removed and sampled for histopathological, immunohistochemical, and ultrastructural investigations. The study revealed that the lens of 12 rats from a total of 40 rats of the second group (diabetic untreated) depicted the onset of cataract at 16 week, which increased gradually. The retina of the same group showed gradual inter-retinal microvascular abnormalities and histopathological changes. The third group (diabetic treated) showed marked amelioration as compared to the second group. ANOVA test for the biomedical indicators showed a statistically significant improvement in the third group. In conclusion, the pomegranate peel extract possesses strong potential for its development as a protective agent against ocular complications of diabetes.

Keywords: Pomegranate peel extract, diabetes mellitus, ocular structure, rats.

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