Abstract
Genetic studies have linked EPHX2 (encoding soluble epoxide hydrolase, sEH) and PTGS2 (encoding cyclooxygenase-2, COX-2) to Alzheimer's disease (AD). Elevated levels of sEH and COX-2 found in AD patients and animals suggest their involvement in neurodegeneration, glial activation, vascular dysfunction, and inflammation. This study evaluated the effects of a new dual sEH/COX-2 inhibitor, PTUPB, on cerebrovascular function and cognition in TgF344-AD rats. The rats received oral PTUPB (2 mg/kg/day) for 25 days. Body weight, plasma glucose, and HbA1c levels remained stable between PTUPB- and vehicle-treated AD rats. PTUPB significantly improved recognition memory in AD rats, as detected by the Novel Object Recognition test. Pressure myography showed that PTUPB restored myogenic responses and increased the distensibility of the middle cerebral arteries (MCAs) in AD rats. Acute PTUPB (0.1 and 1 μM) enhanced myogenic contraction in response to elevated perfusion pressure in AD MCAs, with minimal effects in wild-type vessels. Vehicle-treated AD rats displayed impaired functional hyperemia, whereas PTUPB (1 μM) significantly restored this response. Transcriptomic analysis of cerebral vascular smooth muscle cells from AD rats indicated that PTUPB influences genes related to contractility, extracellular matrix remodeling, inflammation, and oxidative stress. These results provide new evidence that dual inhibition of sEH and COX-2 improves cognition in AD, likely by enhancing myogenic response and increasing cerebral artery distensibility. Our findings highlight the potential of PTUPB as a therapeutic approach for cerebrovascular dysfunction in AD.