Comparative Histological Study on the Effect of Allium Sativum (Garlic), Allium Cepa (Onion) and Insulin on Lingual Papillae of Diabetic Rats

Introduction: Diabetes mellitus (DM) is a common chronic metabolic disease. Various inflammatory diseases and soft tissue pathologies are associated with DM. Major concern in diabetes is oxidative stress. Antioxidants prevent diabetic complications. Onion & garlic are strong antioxidants, so this study was done to determine their possible effect in minimizing complications that diabetic patients suffer, compared to insulin.
Materials and Methods: Fifty Albino rats were divided into 5 groups, ten rats each; Control, untreated streptozotocin induced diabetic group, diabetic insulin treated, diabetic garlic treated and diabetic onion treated groups. On the 21st day of the experiment, rats were sacrificed and tongue specimens were prepared and examined by H&E for routine histological examination and by scanning Electron Microscope.
Results: Histological changes of tongue papillae of diabetic untreated rats were observed, such as thinning of the epithelium of all papillae, numerous intra-epithelial cell vacuolations, thin detached keratin, extrcellular edema and inflammatory cell infiltrate within the lamina properia of all papillae. After, administration of insulin, garlic and onion, tongue papillae appeared almost normal compared to control group. However, the onion group displayed apparently slight better morphological and structural findings than garlic group.
Discussion: Circumvallate papillae were most affected may be due to difference in their gustatory nerve supply. Other papillae in both garlic and onion treated groups, appeared almost normal. Which can be explained by the hypoglycemic, antimicrobial, anti-inflammatory effect of both extracts.
Conclusion: Garlic and onion oral intake during early phases of diabetes caused valuable improvement of tongue papillae which was highly comparable to insulin treatment.