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Objective Astrocytes actively participate in energy metabolism in the brain, and astrocytic aerobic glycolysis disorder is associated with the pathology of Alzheimer's disease (AD). GLP-1 has been shown to improve cognition in AD; however, the mechanism remains unclear. The objectives of this study were to assess GLP-1's glycolytic regulation effects in AD and reveal its neuroprotective mechanisms. Methods The Morris water maze test was used to evaluate the effects of liraglutide (an analog of GLP-1) on the cognition of 4-month-old 5 FAD mice, and a proteomic analysis and Western blotting were used to assess the proteomic profile changes. We constructed an astrocytic model of AD by treating primary astrocytes with Aβ 1-42 . The levels of NAD+ and lactate were examined, and the oxidative levels were assessed by a Seahorse examination. Astrocyte-neuron co-culture was performed to evaluate the effects of GLP-1 on astrocytes’ neuronal support. Results GLP-1 improved cognition in 4-month-old 5 FAD mice by enhancing aerobic glycolysis and reducing oxidative phosphorylation (OXPHOS) levels and oxidative stress in the brain. GLP-1 also alleviated Aβ-induced glycolysis declines in astrocytes, which resulted in reduced OXPHOS levels and reactive oxygen species (ROS) production. The mechanism involved the activation of the PI3K/Akt pathway by GLP-1. Elevation in astrocytic glycolysis improved astrocyte cells’ support of neurons and promoted neuronal survival and axon growth. Conclusions Taken together, we revealed GLP-1's capacity to regulate astrocytic glycolysis, providing mechanistic insight into one of its neuroprotective roles in AD and support for the feasibility of energy regulation treatments for AD.

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Objective. To investigate refractive development and prevalence of myopia in children aged 3-6 years in Hebei Province, China, and to explore the developmental law of refraction, so as to clinically guide the prediction and intervention of myopia. Methods. In May 2019, a total of 6120 people were inspected in 68 kindergartens in 11 cities in Hebei Province. Child refractive refraction was checked under noncycloplegia using a handheld binocular vision screener (SW-800, SUOER, Tianjin, China). Axial length (AL) and corneal radius of curvature (CR) were measured using an ocular biometry (IOLMaster 500, Carl Zeiss, Germany). Myopia was defined as spherical equivalent SE ≤ − 0.75   D . Results. A total of 5506 children aged 3-6 years met the criteria and were included in the statistical analysis. The prevalence of myopia was 3.49% (1.93% at age 3, 2.90% at age 4, 3.78% at age 5, and 3.88% at age 6). Overall, the mean SE was + 0.67 ± 1.05   D ( + 0.81 ± 1.00   D at age 3, + 0.79 ± 1.05   D at age 4, + 0.67 ± 1.08   D at age 5, and + 0.13 ± 1.01   D at age 6); the mean CR was 7.76 ± 0.26   mm ( 7.78 ± 0.26   mm at age3, 7.75 ± 0.25   mm at age 4, 7.77 ± 0.26   mm at age 5, and 7.76 ± 0.25   mm at age 6); the mean AL was 22.31 ± 0.73   mm ( 21.98 ± 0.63   mm at age 3, 22.12 ± 0.69   mm at age 4, 22.34 ± 0.73   mm at age 5, and 22.49 ± 0.73   mm at age 6). Conclusions. Prevalence of myopia increases with age in children aged 3-6 years in Hebei, China. With the increase of age, CR is basically stable, and AL increases gradually. AL/CR, which is closely related to SE, can be used as an indicator to predict myopia and guide clinical work.