Men and women with multiple sclerosis show differing rates of relapse and remission based on gene expression regulation.
A Spanish study showed that relapse and remission in multiple sclerosis (MS) states are regulated by small non-coding RNA (sncRNA) molecules in patterns differing between men and women.
Scientists have increasingly realized that sncRNAs play an important role in the regulation of gene expression. Various kinds of these RNA molecules, such as micro RNA (miRNA) or small nucleolar RNA (snoRNA), can bind to DNA and increase or decrease gene expression.
The research team from the Biodonostia Institute, San Sebastian, Spain, wanted to explore if this type of gene regulation affects the cycles in relapsing-remitting MS (RRMS). They collected blood samples from 24 individuals with RRMS and an equal number of controls. Two blood samples were drawn from the MS patients, during remission and again during relapse.
According to the article — “SncRNA (microRNA & snoRNA) opposite expression pattern found in multiple sclerosis relapse and remission is sex dependent“ — the researchers isolated RNA from immune cells in the blood samples, and analyzed the relative amounts of sncRNAs. Since rates and clinical features differ between men and women, the team analyzed the results based on sex, but also analyzed the group as a whole.
To exclude any possibility that altered treatment induced changes in RNA levels, only patients who were receiving the same treatment in both disease phases were included in the comparison between relapse and remission. This resulted in two groups of patients — 13 receiving the same treatment during relapse and remission, and another 11 who received different treatment. When the team compared patients with healthy controls, all 24 MS patients were included in the analyses.
Investigating the expression of sncRNAs using a microarray, the team identified 23 sncRNAs that were dysregulated in relapse. The results, published in the journal Scientific Reports, also showed that when dividing the analysis by sex, 38 sncRNAs were differentially expressed in women and none in men. Likewise, the team observed 51 altered sncRNAs in remission when looking at all samples, as well as 42 in samples from women, and seven in samples from men.