Skip to main content
Fig. 4 | Journal of Neuroinflammation

Fig. 4

From: Anti-inflammatory role of GM1 and other gangliosides on microglia

Fig. 4

Anti-inflammatory effects of GM1 require the presence of sialic acid and a lipid tail and are shared by other gangliosides, but not GM3 or GQ1b. A Mouse primary microglia were stimulated for 3 h with LPS (100 ng/ml), washed and further incubated with GM1- or GA1-loaded liposomes (200 µM liposome concentration). Naked liposomes were used as a control. TNF and IL-1β mRNA levels were measured by qPCR. Data are presented as percentage expression change compared to activated microglia incubated with control naked liposomes (N = 3–4). B Mouse primary microglia were stimulated with LPS and washed as in A, prior to incubation with GM1, GM1-pentasaccharide (GM1ps) or truncated azido-GM1ps (tGM1) (50 µM each) for 8 h. In parallel experiments, activated microglia were incubated with control naked liposomes or GM1- or GM1-DSPE-loaded liposomes (200 µM each—pink shaded area) for 8 h (N = 3–4). C Simplified scheme of the ganglioside biosynthetic pathway and related enzymes. L–t-PDMP is an activator and GENZ-123346 is an inhibitor of UDP-glucose ceramide glucosyltransferase (UGCG). The shaded grey area highlights the major brain gangliosides. Glucose: blue circle; galactose: yellow circle; N-acetylgalactosamine: yellow square; N-acetylneuraminic acid: purple diamond. D Mouse primary microglia stimulated with LPS (100 ng/ml) for 3 h were washed and further incubated with naked liposomes, GM1- or GM3-loaded liposomes (200 µM each—pink shaded area) or the indicated gangliosides (all at 50 µM in PBS) for 8 h. Data are presented as the percentage expression change compared to activated microglia incubated with vehicle controls (naked liposomes or PBS) (N = 3–7). E LPS-stimulated microglia were washed and incubated with GM1- or GM3-containing liposomes (200 µM), or with GM3-liposomes in the presence of GM1 in micellar form (50 µM) for 8 h. Co-administration of GM1 abrogated the pro-inflammatory effects of GM3. Data are presented as percentage gene expression change over LPS-activated microglia treated with vehicle. Mean values ± STDEV are shown. A two-tailed t-test was used to compare the effect of each treatment to their respective vehicle controls. *p < 0.05, **p < 0.01. One-way ANOVA with Sidak’s multiple comparisons test was used in B, D and E to compare the effect of GM1 to other gangliosides. p < 0.05, ✝✝✝✝p < 0.0001

Back to article page