Atorvastatin Calcium Ameliorates Cognitive Deficits Through the AMPK/Mtor Pathway in Rats with Vascular Dementia.

AIM: In this study, the protective effects of atorvastatin calcium (AC) on nerve cells and cognitive improvement in vivo and in vitro were investigated by establishing cell models and vascular dementia (VD) rat models. BACKGROUND: VD is a neurodegenerative disease characterized by cognitive deficits caused by chronic cerebral hypoperfusion. AC has been studied for its potential to cure VD but its efficacy and underlying mechanism are still unclear. OBJECTIVE: The mechanism of action of AC on cognitive deficits in the early stages of VD is unclear. Here, the 2-vessel occlusion (2-VO) model in vivo and the hypoxia/reoxygenation (H/R) cell model in vitro was established to investigate the function of AC in VD. METHODS: The spatial learning and memory abilities of rats were detected by the Morris method. The IL-6, tumour necrosis factor-α (TNF-α), malondialdehyde (MDA) and superoxide dismutase (SOD) in cell supernatant was tested by ELISA kits. After behavioural experiments, rats were anaesthetized and sacrificed, and their brains were extracted. One part was immediately fixed in 4% paraformaldehyde for H&E, Nissl, and immunohistochemical analyses, and the other was stored in liquid nitrogen. All data were shown as mean ± SD. Statistical comparison between the two groups was performed by Student's t-test. A two-way ANOVA test using GraphPad Prism 7 was applied for escape latency analysis and the swimming speed test. The difference was considered statistically significant at p < 0.05. RESULTS: AC decreased apoptosis, increased autophagy, and alleviated oxidative stress in primary hippocampal neurons. AC regulated autophagy-related proteins in vitro by western blotting. VD mice improved cognitively in the Morris water maze. Spatial probing tests showed that VD animals administered AC had considerably longer swimming times to the platform than VD rats. H&E and Nissl staining showed that AC reduces neuronal damage in VD rats. Western blot and qRT-PCR indicated that AC in VD rats inhibited Bax and promoted LC3-II, Beclin-1, and Bcl-2 in the hippocampus region. AC also improves cognition via the AMPK/mTOR pathway. CONCLUSION: This study found that AC may relieve learning and memory deficits as well as neuronal damage in VD rats by changing the expression of apoptosis/autophagy-related genes and activating the AMPK/mTOR signalling pathway in neurons.

Photo- and thermo-activated electron transfer system based on a luminescent europium organic framework with spectral response from UV to visible range.

A dual stimuli-responsive system was constructed by introducing methyl viologen into a luminescent europium-organic framework with a compact packing mode. In addition to absorption and emission properties that are sensitive to both light and heat involving electron/energy transfer processes, the photoactive MOF has a spectral response from UV to the visible region.

Highly stable photoresponsive complex framework formation involves unusual selective hydrogenation of a pyridine derivative.

A unique hydrothermal selective hydrogenation process is carried out effectively in a simple and friendly way without adding any precious metal catalysts and hydrogen gas from outside. The self-assembly of the hydrogenated product 3-(4-(pyridin-4-yl)piperidin-1-yl) benzoate (PYPDB) with the zinc ion produces a highly stable photoactive complex Zn(PYPDB)2 displaying interesting long range electron transfer behavior in the conjugated ring system.