Comparison of the Neuroprotective and Anti-Inflammatory Effects of the Anthocyanin Metabolites, Protocatechuic Acid and 4-Hydroxybenzoic Acid

Figure 5

HBA, but not PCA, protects CGNs from glutamate-induced excitotoxicity. (a) Representative images of untreated control CGNs (Con), CGNs treated with glutamate alone (G/G), and CGNs treated in combination with glutamate and either 500 μM 4-hydroxybenzoic acid (HBA) or 500 μM protocatechuic acid (PCA). Top panels show decolorized Hoechst fluorescence to visualize nuclei. Bottom panels show bright field images to visualize neuronal cell bodies and processes. Scale bar = 10 μm. Arrowheads indicate apoptotic nuclei, and asterisks indicate healthy nuclei (top panels) of CGNs within the boxes demarcated in the corresponding bottom panels. (b) Quantitative assessment of apoptosis in CGNs treated with glutamate alone or in combination with various concentrations of HBA. (c) Quantitative assessment of apoptosis in CGNs treated with glutamate alone or in combination with various concentrations of PCA. For quantification, nuclear morphology was assessed, and cells displaying condensed or fragmented nuclei were scored as apoptotic. The percent of all total cells that displayed apoptotic morphology was then determined. Data are represented as mean ± SEM for experiments. indicates and indicates in comparison to untreated controls; ††† indicates in comparison to cells treated with glutamate alone by one-way ANOVA with a post hoc Tukey’s test.

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