Microarray analysis identifies altered regulation of nuclear receptor family members in the pre-disease state of multiple sclerosis

Abstract

Molecular mechanisms that influence susceptibility to multiple sclerosis are poorly understood. We analyzed peripheral blood gene expression profiles in nine healthy subjects up to nine years before the onset of multiple sclerosis in comparison with 11 age-, gender-, and origin-matched healthy subjects who remained multiple sclerosis-free, and 31 subjects during the first clinical episode of multiple sclerosis. Within the 1051 highly variable genes that differentiated between multiple sclerosis-to-be and multiple sclerosis-free subjects, we identified activation of TCR signaling that triggered the Cbl and MAPK cascade in concert with downstream synergic over-expression of NFAT and MEF2B, but failed to augment the expression of the nuclear receptor gene family members NR4A1, NR2F1, VDR and MEF2B, that further resulted in impaired apoptotic machinery. Comparison between multiple sclerosis-to-be and first clinical onset of multiple sclerosis operating module networks demonstrated the evolution of altered regulation of nuclear receptor-dependent apoptosis. Our findings demonstrating a silent multiple sclerosis trait that is associated with suppressed expression of the nuclear receptor network and inhibited apoptosis of activated T-cells support the role of these transcription signals in the evolution of the autoimmune processes that operate in the pre-disease stage of multiple sclerosis.