Purpose: The objective of this study was to determine whether diabetes mellitus (DM)-induced up regulation of 14-3-3 beta (YWHAB) in endothelial cells enhances intimal hyperplasia in carotid artery injured DM Sprague-Dawley (SD) rats. Methods: YWHAB expression and rat aortic endothelial cell (RAOEC) vitality were examined using Cell Counting Kit-8 (CCK-8), quantitative reverse transcription PCR (qRT-PCR), and western blot analysis in cells treated with different glucose concentrations (5.6, 10, 15, 25, or 35 mM). For in vivo experiments, a YWHAB small interfering (si) RNA recombinant lentiviral vector (YWHAB-LV) or Mock siRNA recombinant lentiviral vector (Mock-LV) were injected into streptozotocin-induced DM SD rats via the tail vein. YWHAB expression and carotid artery morphology were assessed 7 days post injury using immunofluorescence (IF) and hematoxylin-eosin (HE) staining. The proliferation and migration of Mock-LV and YWHAB-LV-infected RAOECs treated with 25 mM glucose were examined using cell scratch tests and flow cytometry. BCL2-Associated X (BAX) distribution in RAOECs treated with 25 mM glucose was examined using IF staining and western blot analysis. Results: Western blot, qRT-PCR, and CCK-8 analyses demonstrated that both YWHAB expression and cell vitality increased with increasing glucose concentration (p < 0.05). YWHAB IF staining was increased in DM rats compared with the normal group (p < 0.05). HE staining showed that intimal hyperplasia is alleviated in YWHAB-silenced DM rats (p < 0.05). YWHAB silencing suppressed the proliferation and migration of RAOECs treated with 25 mM glucose (p < 0.05). Moreover, western blot analyses and IF staining demonstrated that YWHAB silencing increased the translocation of BAX from the cytoplasm to. mitochondria in RAOECs treated with 25 mM glucose (p < 0.05). Conclusions: Our results indicate that hyperglycemia-induced up-regulation of YWHAB in endothelial cell plays a significant role in intimal hyperplasia following carotid artery injury by enhancing endothelial cell proliferation and migration. YWHAB inhibition in hyperglycemic patients may constitute a potential target for therapeutic interventions via restenosis prevention. (C) 2017 Elsevier Inc. All rights reserved.