# Downregulation of dual-specificity phosphatase 1 (DUSP1) in post-mortem brain white matter in progressive multiple sclerosis

## TL;DR

This study finds that DUSP1, a protein involved in regulating cell signaling, is reduced in brain white matter of people with progressive multiple sclerosis.

## Contribution

The novel finding is that DUSP1 is downregulated in white matter tissue from progressive MS patients compared to controls.

## Key findings

- DUSP1 is significantly downregulated at both gene and protein levels in MS white matter tissue.
- DUSP1 is expressed on Iba1+ cells in the brain, and ITGAM (CD11b) expression is elevated in MS white matter.

## Abstract

Dual-specificity phosphatase 1 (DUSP1) is a negative regulator of mitogen-activated protein kinase (MAPK) activity, and a player in the control of glial function. Several disease models have identified that the expression of DUSP1 is altered in tissue samples, which may contribute to disease pathogenesis. Using post-mortem brain tissue from a cohort of progressive multiple sclerosis (MS) cases, this study set out to determine if the expression of DUSP1 is altered in the brain in MS.

We employed the use of a combination of PCR, western immunoblotting and immunohistochemical analysis to profile the expression of DUSP1.

Data presented herein indicate that DUSP1 is significantly downregulated at gene and protein level in MS white matter tissue, when compared to samples from a non-MS control cohort. We also identify that DUSP1 is expressed on Iba1+ cells in the brain and that ITGAM (CD11b) expression is elevated in white matter in progressive MS.

These findings provide evidence that DUSP1 is dysregulated centrally in CNS white matter in progressive MS.

The online version contains supplementary material available at 10.1007/s10072-026-08944-2.