17β-Estradiol Regulates Microglia Activation and Polarization in the Hippocampus Following Global Cerebral Ischemia

Figure 4

Estrogen suppresses protein levels of M1 markers and upregulates protein levels of M2 markers in the hippocampus after global cerebral ischemia. (a) Representative confocal microscopy images of M1 markers, CD68 and iNOS, in shams and GCI as well as GCI + E2 treatment groups at 7 days after GCI indicate upregulation after GCI and suppression under the effect of E2 (magnification = 40x, scale bar = 50 μm). (b, c) Quantification of intensity of confocal microscopy staining in 5A (n = 5-6 animals per group). (d, e) Western blot analysis of classical M1 marker, CD68, in sham and GCI as well as GCI + E2 treatment groups at 7 days after GCI. Quantification of blots indicates a significant increase in CD68 after GCI and suppression under the effect of E2. (f) Representative confocal microscopy images of M2 markers, CD206 and IL1RA, in shams and GCI as well as GCI + E2 treatment groups at 7 days after GCI indicate downregulation after GCI and upregulation under the effect of E2 (magnification = 40x, scale bar = 50 μm). (g, h) Quantification of intensity of confocal microscopy staining in 5F. (i, j) Western blot analysis of classical M2 marker, CD206, in sham, GCI, and GCI + E2 treatment groups at 7 days after GCI. Quantification of Western blots shows that there is not a change in CD206 expression after GCI. However, E2 treatment with GCI leads to a significant upregulation of CD206 (n = 5-6 animals per group) (, sham versus GCI, , GCI versus GCI + E2).

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