{Reference Type}: Journal Article {Title}: Increased Permeability of the Blood-Brain Barrier in a Diabetic Mouse Model (Leprdb/db Mice). {Author}: Alshammari MA;Alshehri AO;Alqahtani F;Khan MR;Bakhrebah MA;Alasmari F;Alshammari TK;Alsharari SD; {Journal}: Int J Mol Sci {Volume}: 25 {Issue}: 14 {Year}: 2024 Jul 16 {Factor}: 6.208 {DOI}: 10.3390/ijms25147768 {Abstract}: Type 2 Diabetes Mellitus (T2DM) is linked to multiple complications, including cognitive impairment, and the prevalence of memory-related neurodegenerative diseases is higher in T2DM patients. One possible theory is the alteration of the microvascular and macrovascular environment of the blood-brain barrier (BBB). In this study, we employed different approaches, including RT-PCR, functional pharmacokinetic studies using sodium fluorescein (NaFL), and confocal microscopy, to characterize the functional and molecular integrity of the BBB in a T2DM animal model, leptin receptor-deficient mutant mice (Leprdb/db mice). As a result, VCAM-1, ICAM-1, MMP-9, and S100b (BBB-related markers) dysregulation was observed in the Leprdb/db animal model compared to littermate wild-type mice. The brain concentration of sodium fluorescein (NaFL) increased significantly in Leprdb/db untreated mice compared to insulin-treated mice. Therefore, the permeability of NaFL was higher in Leprdb/db control mice than in all remaining groups. Identifying the factors that increase the BBB in Leprdb/db mice will provide a better understanding of the BBB microvasculature and present previously undescribed findings of T2DM-related brain illnesses, filling knowledge gaps in this emerging field of research.