en فيزيولوژي Physiology پژوهشي Research <div style="text-align: justify;"><span style="font-size:11pt"><span style="line-height:normal"><span style="unicode-bidi:embed"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:#2f5496">Background & Objectives:</span></span></span></b><b> </b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times="">Diabetes is the most common metabolic disease, associated with hyperglycemia and long-term complications. This study aimed to elucidate the anti-diabetic role of oleuropein (OLE) in a streptozotocin (STZ)-induced diabetic animal model. </span></span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span style="unicode-bidi:embed"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:#2f5496">Materials & Methods:</span></span></span></b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""> Adult male Wistar rats (200&ndash;250 g) were randomly divided into four groups: 1) Control group, 2) STZ group: diabetic rats that received STZ (60 mg/kg), 3) OLE 50 group: diabetic rats treated with oral OLE at 50 mg/kg of body weight daily for 28 days, and 4) OLE 100 group: diabetic rats treated with oral OLE at 100 mg/kg of body weight daily for 28 days. Memory function and biochemical factors such as malondialdehyde (MDA) levels, glutathione peroxidase (GPx), and total thiol activity were evaluated in the rats&#39; cerebral cortex and striatum tissues. Moreover, nuclear transcription factor-kappa B (NF-&kappa;B) and nuclear factor E2-related factor 2 (Nrf2) pathway activation were determined in cerebral cortex and striatum tissues by real-time polymerase chain reaction (PCR).</span></span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span style="unicode-bidi:embed"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:#2f5496">Results:</span></span></span></b><b> </b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times="">Chronic administration of OLE ameliorated cognitive deficits and attenuated oxidative stress induced by diabetes. Additionally, OLE significantly prevented the activation of the pro-inflammatory marker NF-&kappa;B and downregulated Nrf2 expression in STZ-induced diabetic rats.</span></span></span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span style="unicode-bidi:embed"><span sans-serif="" style="font-family:Calibri,"><b><span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times=""><span style="color:#2f5496">Conclusion:</span></span></span></b> <span style="font-size:12.0pt"><span new="" roman="" style="font-family:" times="">Our results confirm the significant protective role of OLE against STZ-induced diabetes in rats by up-regulating Nrf2 signaling and enhancing antioxidant activity.</span></span></span></span></span></span></div> <br> &nbsp; ‎Diabetes , Oleuropein , Oxidative stress , Memory , Nrf-2 , Rat 115 127 http://jabs.fums.ac.ir/browse.php?a_code=A-10-3380-1&slc_lang=en&sid=1 Zahra Shaibani زهرا شیبانی shaibani73@gmail.com 100319475328460028995 100319475328460028995 No Department of Biology, Payam Noor University, Tehran, Iran گروه زیست شناسی، دانشکده علوم پایه، دانشگاه پیام نور، تهران، ایران Maryam Rafieirad مریم رفیعی راد rafieirad.m@gmail.com 100319475328460028996 100319475328460028996 Yes Department of Biology, Izeh branch, Islamic Azad University, Izeh, Iran گروه زیست شناسی، دانشگاه آزاد اسلامی، واحد ایذه، ایذه، ایران