Cellular and Molecular NeuroscienceResearch PaperDisruption of neuronal-glial-vascular units in the hippocampus of ovariectomized mice injected with d-galactose
Section snippets
Animal treatment
Four-months-old female ICR mice (National Rodent Laboratory Animal Resources, Shanghai Branch, PR China) were maintained under a 12-h light/12-h dark cycle, and allowed free access to food and water. Animals were randomly divided into two groups. (1) Model group: Mice were anesthetized with 3.5% chloral hydrate (Sinopharm Chemical Reagent Co., Ltd., Shanghai, China) received bilateral ovariectomy, and then 1% d-gal (Sigma Chemical Company, St. Louis, MO, USA; 100 mg/kg body weight) dissolved in
Reactive astrogliosis in the hippocampus of model mice
In a recent study, we have demonstrated alterations of brain oxidant/antioxidant system and mitochondrial damage in hippocampal neurons and synapses of OVX mice chronically injected with d-gal (Su et al., 2010). We further investigated whether oxidative damage triggers reactive astrogliosis in the hippocampus, by using GFAP immunostaining combined with quantitative analysis. A large number of GFAP-IR astrocytes exhibited a regular distribution pattern in the hippocampus of sham group (Fig. 1A).
Discussion
In the last few decades, tremendous advances in biology and function of glial cells, especially astrocytes, help us to recognize brain organization and function (Allen and Barres, 2009). We now learn that astroglial cells are responsible for integrating neurons, synapses, and brain capillaries into inter-dependent functional units. Loss of functional organization of neuronal-glial-vascular units may play critical roles in the pathogenesis of neurological disorders including AD (Guo and Lo, 2009
Conclusion
In summary, the present study confirmed that subcellular organizations of neuroglial and gliovascular units were disrupted in the hippocampus of OVX mice injected with d-gal. Moreover, we found that reactive astrogliosis caused decreases in GLT1, GLAST, GS and Cx43 expressions and an increase of AQP4 expression in the hippocampus of model mice. These results provide clear evidence that astrocyte dysfunction including glutamate clearance, water transport and astrocyte syncytium are associated
Acknowledgments
We thank Ms. Qing Ru for technical assistance with the electron microscopy and the two anonymous reviewers for their insightful comments. This work was supported by the grants from National Natural Science Foundation of China (Nos. 30971020 and 30973517), Natural Science Foundation of Jiangsu Educational Department (09KJA310003) and Jiangsu Qing Lan Project.
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