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Chronic neuromicrovascular dysfunction and its induced multifaceted neuropathology involving the interaction of cellular differential pathogenic mechanisms pose challenges to the precise treatment of Alzheimer's disease (AD). Here we report the development of an ellagic acid-derived self-assembled micellar SIRT1 activator (REn) that enables cross-scale targeted remodeling of neurovascular and neurometabolic coupling in AD. Efficient transcytosis of the receptor for advanced glycation endproducts by modified peptides allows for programmed delivery of REn to cerebral microvessels and parenchymal neurons. The resulting SIRT1 cascade activation enhances endothelial nitric oxide signaling-mediated cerebral blood flow and the blood-brain barrier integrity, while promoting neuronal mitochondrial biogenesis and glucose metabolic patterns toward oxidative phosphorylation. This multipronged remodeling strategy achieves a cooperative normalization of brain energy supply and β-amyloid clearance in AD mice, showing profound improvement in cognitive impairment. This work provides an advanced pharmacological option for cross-scale targeted treatment of neurodegenerative diseases associated with neurovascular dysfunction. [Display omitted] • Natural self-assembled SIRT1 activator is developed for cross-scale AD treatment. • REn is programmed to be delivered to cerebral microvessels and parenchymal neurons. • REn activates endothelial SIRT1 to repair neurovascular dysfunction. • REn activates neuronal SIRT1 to improve brain metabolism dyshomeostasis. • REn remodels neurovascular and neurometabolic coupling against AD. [ABSTRACT FROM AUTHOR]

Aims: The aims of this study were to assess vascular dysfunction in patients with Alzheimer disease (AD) by investigating cerebral vasomotor reactivity using transcranial Doppler ultrasound (TCD) and to evaluate any correlations between cerebral vasoreactivity and endothelium dysfunction. Moreover, the frequency of circulating progenitor cells (CPCs) and the blood concentration of vascular/inflammatory markers were evaluated.Materials and Methods: We recruited 35 AD subjects and 17 age-matched, sex-matched, and education-matched healthy control subjects. Cerebral vasomotor reactivity was assessed by means of the TCD-based breath-holding index test (BHI). The level of CPCs was evaluated by means of flow cytometry from venous blood samples, while blood vascular/inflammatory markers were measured by means of enzyme-linked immunosorbent assay.Results: Both cerebral assay blood flow velocity in the middle cerebral artery (MCAFV) and BHI values were significantly lower in AD subjects than in healthy controls (P<0.05). A positive trend was found between MCAFV and BHI values and Mini-Mental State Evaluation (MMSE) scores. Moreover, the hematopoietic progenitor cells' count was found to be lower in patients with AD than in controls (P<0.05). Finally, a significantly higher expression of the plasma chemokine CCL-2 was observed in AD patients than in healthy controls.Conclusions: Our results confirm that cerebral hemodynamic deterioration may be a critical marker of cognitive decline. Further studies are needed to investigate the role of circulating CPCs and chemokines as potential contributors to neurovascular dysfunction. [ABSTRACT FROM AUTHOR]

Introduction We examined whether cortical microvascular blood volume and hemodynamics in Alzheimer's disease (AD) are consistent with tissue hypoxia and whether they correlate with cognitive performance and the degree of cortical thinning. Methods Thirty-two AD patients underwent cognitive testing, structural magnetic resonance imaging (MRI), and perfusion MRI at baseline and after 6 months. We measured cortical thickness, microvascular cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and capillary transit time heterogeneity (CTH) and estimated tissue oxygen tension (P t O 2 ). Results At baseline, poor cognitive performance and regional cortical thinning correlated with lower CBF and CBV, with higher MTT and CTH and with low P t O 2 across the cortex. Cognitive decline over time was associated with increasing whole brain relative transit time heterogeneity (RTH = CTH/MTT). Discussion Our results confirm the importance of microvascular pathology in AD. Deteriorating microvascular hemodynamics may cause hypoxia, which is known to precipitate amyloid retention. [ABSTRACT FROM AUTHOR]

Background: The pathological impact of chronic cerebral hypoperfusion (CCH) on Alzheimer's disease (AD) is still poorly understood. In the present study, we investigated the role of CCH on an AD mouse model in phosphorylated tau and α-synuclein pathology, neurovascular unit, cerebrovascular remodeling, and neurovascular trophic coupling. Moreover, examined protective effect of a new antioxidant Twendee X (TwX).Methods: APP23 mice were implanted to bilateral common carotid arteries stenosis with ameroid constrictors to gradually decrease the cerebral blood flow. The effects of the administration of TwX were evaluated by immunohistochemical analysis and Immunofluorescent histochemistry.Results: The present study revealed that the expressions of phospho-tau and phospho-α-synuclein were significantly increased in the APP23 + CCH mice group as compared with wild type and APP23 mice groups (*P < .05 and ⁎⁎P < .01 versus WT; #P < .05 and ##P < .01 versus APP23). In addition, CCH significantly exacerbated MMP-9 activation relating to blood-brain barrier destruction (⁎⁎P < .01 versus WT; #P < .05, and ##P < .01 versus APP23), enhanced neurovascular remodeling, and impaired a neurovascular trophic coupling in the vascular endothelial BDNF expression of the APP23 + CCH group. TwX treatment (20 mg/kg/day, from 4.5 to 12 months) significantly reduced tau and α-synuclein pathologies, ameliorated neurovascular dysfunction compared with APP23 + CCH group.Conclusions: Our findings indicate that administration of a new antioxidative mixture TwX substantially reduced the above neuropathologic abnormalities, suggesting a potential therapeutic benefit of TwX for AD with CCH. [ABSTRACT FROM AUTHOR]