The immunomodulator effect of Stevia rebaudiana Bertoni mediated by TNF-α and IL-1β in peripheral blood in diabetic rats

Abstract

Stevia rebaudiana Bertoni, which is a medicinal plant used in the treatment of diabetes, was the focus of this study aiming to investigate its immunomodulatory properties in diabetes. To form the diabetes group, rats were injected intraperitoneally with STZ and rats with blood glucose levels above 200 mg/dL 2 days after STZ injection were included in the diabetes group. To form the stevia and diabetes + stevia groups, stevia was administered daily by gavage to both healthy and diabetic rats for 28 days. At the end of 28 days, the levels of interleukin-1 beta and tumor necrosis factor-alpha in the blood were measured by ELISA. CD3, CD4, and CD8 protein levels in the blood were determined by flow cytometry. Rat body weight increased in the diabetes +25 mg/kg bW stevia group compared with the diabetes group. Blood glucose levels were significantly decreased in the diabetes +25 mg/kg bW stevia group compared to the diabetes group (**p < .01). IL-1β cytokine levels decreased significantly in the diabetes +25 mg/kg bW stevia group compared to the diabetes group (**p < .01). TNF-α cytokine levels decreased significantly in the diabetes +25 mg/kg bW stevia group compared to the diabetes group (**p < .01). The amount of CD8 + T cells decreased significantly in the diabetes +25 mg/kg bW stevia group compared to the diabetes group (*p < .05). The stevia diet leads to a reduction in peripheral circulating cytotoxic T cells and proinflammatory cytokines interleukin-1 beta and tumor necrosis factor-alpha under hyperglycemic conditions.