Early strong intrathecal inflammation in cerebellar type multiple system atrophy by cerebrospinal fluid cytokine/chemokine profiles: a case control study

Abstract

Background: The pathology of multiple system atrophy cerebellar-type (MSA-C) includes glial inflammation; however, cerebrospinal fluid (CSF) inflammatory cytokine profiles have not been investigated. In this study, we determined CSF cytokine/chemokine/growth factor profiles in MSA-C and compared them with those in hereditary spinocerebellar ataxia (SCA).

Methods: We collected clinical data and CSF from 20 MSA-C patients, 12 hereditary SCA patients, and 15 patients with other non-inflammatory neurological diseases (OND), and measured 27 cytokines/chemokines/growth factors using a multiplexed fluorescent bead-based immunoassay. The size of each part of the hindbrain and hot cross bun sign (HCBS) in the pons was studied by magnetic resonance imaging.

Results: Granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin (IL)-6, IL-7, IL-12, and IL-13 levels were significantly higher in MSA-C and SCA compared with OND. In MSA-C, IL-5, IL-6, IL-9, IL-12, IL-13, platelet-derived growth factor-bb, macrophage inflammatory protein (MIP)-1α, and GM-CSF levels positively correlated with anteroposterior diameters of the pontine base, vermis, or medulla oblongata. By contrast, in SCA patients, IL-12 and MIP-1α showed significant negative correlations with anteroposterior diameters of the pontine base, and unlike MSA-C, there was no cytokine with a positive correlation in SCA. IL-6 was significantly higher in MSA-C patients with the lowest grade of HCBS compared with those with the highest grade. Macrophage chemoattractant protein-1 (MCP-1) had a significant negative correlation with disease duration only in MSA-C patients. Tumor necrosis factor-alpha, IL-2, IL-15, IL-4, IL-5, IL-10, and IL-8 were all significantly lower in MSA-C and SCA compared with OND, while IL-1ra, an anti-inflammatory cytokine, was elevated only in MSA-C. IL-1β and IL-8 had positive correlations with Unified Multiple System Atrophy Rating Scale part 1 and 2, respectively, in MSA-C.

Conclusions: Although CSF cytokine/chemokine/growth factor profiles were similar between MSA-C and SCA, pro-inflammatory cytokines, such as IL-6, GM-CSF, and MCP-1, correlated with the disease stage in a way higher at the beginning only in MSA-C, reflecting early stronger intrathecal inflammation.

Keywords: Cerebrospinal fluid; Cytokine; Interleukin-6; Magnetic resonance imaging; Monocyte chemoattractant protein-1; Multiple system atrophy.

Fig. 1

CSF cytokine levels in patients with MSA-C and SCA. a Pleiotropic cytokines. b Th1-related cytokines. c Th2-related cytokines. d IL-17-related cytokines. e Anti-inflammatory cytokines. f Chemokines. g Growth factors. The p values calculated using one-way ANOVA with Bonferroni’s correction are indicated in parenthesis next to the name of the cytokines. Post-hoc analysis was performed using the Tukey test. *p < 0.05, **p < 0.01, ***p < 0.001. CSF: cerebrospinal fluid, IL: interleukin, MSA-C: multiple system atrophy cerebellar-type; SCA: spinocerebellar ataxia, Th: type (1 or 2) T helper cell

Fig. 2

Clustering of correlations between each CSF cytokine level in MSA patients. Color code indicates R values of correlations calculated using Pearson’s correlation coefficient. CSF: cerebrospinal fluid, MSA: multiple system atrophy

Fig. 3

Correlations between disease durations and cytokine levels in MSA-C patients. a Heatmap analysis of correlations between cytokine levels and disease duration. R values of Pearson’s correlation coefficient analysis are divided into quintiles, and p values calculated using one-way ANOVA are indicated as a heatmap. Note the significant negative correlation between MCP-1 and disease duration (R = −0.57, p = 0.0088). b Linear regression analysis shows a strong negative correlation between CSF MCP-1 and disease duration in MSA-C. Mean value ± 2 SD observed in OND patients is indicated as a gray bar (mean ± 2 SD = 378.1 ± 214.4 pg/μL). CSF: cerebrospinal fluid, MCP-1: macrophage chemoattractant protein-1, MSA-C: multiple system atrophy cerebellar-type, OND: other non-inflammatory neurological diseases

Fig. 4

Correlations between UMSARS clinical scores and cytokine levels in MSA-C patients. a Heatmap analysis of correlations between cytokine levels and UMSARS part 1/part 2. R values of Pearson’s correlation coefficient analysis are divided into quintiles, and p values calculated using one-way ANOVA are indicated as a heatmap. Among the 27 cytokines studied, IL-8 and IL-1β showed correlations with UMSARS scores. b, c Linear regression analysis between IL-1β and UMSARS part 1 (R = 0.43, p = 0.0558) (b), and between IL-8 and UMSARS part 2 (R = 0.61, p = 0.0042) (c). IL: interleukin, MSA-C: multiple system atrophy cerebellar-type, UMSARS: Unified Multiple System Atrophy Rating Scale

Fig. 5

Correlations between cytokine levels and MRI measurements of each part of the hindbrain. a Heatmap analysis of correlations between cytokine levels and MRI measurements. R values of Pearson’s correlation coefficient analysis are divided into quintiles, and p values calculated using one-way ANOVA are indicated as a heatmap. Among the 27 cytokines studied, IL-5, IL-6, IL-9, IL-12, IL-13, PDGF-bb, MIP-1α, and GM-CSF showed significant positive correlations with MRI measurements. b Linear regression analysis between cytokine levels and MRI measurements for cytokines that showed significant correlations. R values and p values calculated using Pearson’s correlation coefficient analysis are indicated on each dot plot. *p < 0.05, **p < 0.01. GM-CSF: granulocyte-macrophage colony-stimulating factor, IL: interleukin, MIP: macrophage inflammatory protein, MRI: magnetic resonance imaging, PDGF: platelet-derived growth factor

Fig. 6

Correlations between CSF cytokine levels and HCBS scores in MSA-C patients. a Classification of HCBS. Grade 1, faint hyper-intense anteroposterior line compared with horizontal line; Grade 2, definite HCBS on a single slice; Grade 3, prominent HCBS on two or more sequential slices. b Heatmap of the p-values of one-way ANOVA analysis. Only the IL-6 level significantly correlated with HCBS score (p = 0.0453). c Comparison of CSF IL-6 levels with HCBS scores. The CSF IL-6 level was significantly lower in patients with higher HCBS scores using the Fisher’s PLSD multiple comparison test (p = 0.0142). *p < 0.05. CSF: cerebrospinal fluid, HCBS: hot cross bun sign, IL: interleukin, MSA-C: multiple system atrophy cerebellar-type, PLSD: protected least significant differentiation