New light has been shed on the long-term protective effect of pregnancy in women with Multiple Sclerosis (MS) through a new study.
Research revealed how persistent differences in DNA methylation of genes related to neural plasticity was observed between women living with MS who have never been pregnant (nulligravida) and those who have given birth (parous).
In addition, the research team found that women with MS who have given birth showed slower biological ageing compared to those who have not.
MS is most often diagnosed in women during their childbearing years – usually between 20 and 40 – so understanding the impact of pregnancy on the progression of the disease is very important both for the women themselves and for their healthcare teams.
“We found significantly different levels of DNA methylation at genes associated with neural plasticity pathways at a median of 16.7 years after conception. We also observed slower biological ageing in parous women which is consistent with previous research in healthy women,” said Pia Campagna, PhD student at Monash University and first author of the study.
“Based on these findings, we believe that pregnancy-induced differences in DNA methylation could underlie the long-term protective effect of pregnancy in women with MS.”
DNA methylation is a key epigenetic mechanism that activates or represses gene transcription. Several lines of evidence suggest that DNA methylation may play a role in how pregnancy affects outcomes in women with MS by influencing immune and central nervous system function.
Despite these findings, no study has conducted an epigenome-wide association study of parity in women with MS to date.
Previously, Dr Vilija Jokubaitis from Monash has shown that pregnancy is associated with reduced long-term disability progression, yet exactly how was not known.
Further investigation of this topic could help a better understanding of the underlying drivers of the onset and progression of the disease, and also identify potential targets for new treatments targeting neurodegeneration.
Following the latest study, the group are now set to confirm their results in a prospective and longitudinal cohort of women with and without MS who are planning a pregnancy.
This prospective study will track immunological and genomic changes at multiple timepoints throughout pregnancy and the postpartum period and will allow the researchers to characterise how these changes may protect against disability accumulation in women with MS.
