en Neurophysiology/Pharmacology Neurophysiology/Pharmacology Experimental research article Experimental research article <span style="font-size:12px;"><span style="font-family:Arial;"><strong>Introduction: </strong>Diabetes mellitus is a metabolic disease. This disease is almost associated with depression and impaired pain sensation. Stevia rebaudiana Bertoni (stevia) has a sweet taste and a useful effect in blood glucose control. This study was designed to evaluate the effect of Stevia and Nano-stevia on psychological problems (e.g. depression and pain) induced by diabetes.<br /> <strong>Methods:</strong> By a single intraperitoneal administration of streptozotocin, diabetes mellitus was induced in male Wistar rats. Stevia (20 mg/dl per day for 30 days) and Nano-stevia (20 mg/dl per day for 30 days) were administrated intra-gastrically in diabetic rats. Using the forced swim test (FST) and formalin test, depression and pain behaviors were measured, respectively.&nbsp;<br /> <strong>Results:</strong> The results exhibited that male diabetic rats showed hyperglycemia, depressant-related behavior, and hyperalgesic response. On the other hand, intragastric usage of Stevia (20 mg/dl per day for 30 days) and Nano-stevia (20 mg/dl per day for 30 days) modified the hyperglycemia, depressant-related response, and hyperalgesic effect in diabetic rats. Nano-stevia indicated the maximum significant response rather than Stevia.<br /> <strong>Conclusion: </strong>The results of this study indicate that Stevia and particularly Nano-stevia could be beneficial in managing diabetes and its associated behavioral complications.</span></span> Diabetes, Stevia, Nano-stevia, Depression-related behavior, Pain 219 231 http://ppj.phypha.ir/browse.php?a_code=A-10-496-5&slc_lang=en&sid=1 Neda Mousavi-Niri Neda.mousaviniri@gmail.com 3200319475328460037786 3200319475328460037786 No Department of Biotechnology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Maryam Naseroleslami m.naseroleslami@iautmu.ac.ir 3200319475328460037787 3200319475328460037787 No Department of Cellular and Molecular Biology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Elham Ghanimati lham74gh@gmail.com 3200319475328460037788 3200319475328460037788 No Department of Cellular and Molecular Biology, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran Marzieh Moheb-Alian marziehalian@yahoo.com 3200319475328460037789 3200319475328460037789 No Department of Cellular and Molecular Biology, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran. Faezeh Abdollah-pour faezeh.abdollahpour95@gmail.com 3200319475328460037790 3200319475328460037790 No Department of Cellular and Molecular Biology, Faculty of Advanced Science and Technology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran. Fatemeh Khakpai khakpai@gmail.com 3200319475328460037791 3200319475328460037791 Yes Department of Physiology, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran