Correlation of Vitamin D3 with the Expression of RORγt and Foxp3 mRNAs in the Peripheral Blood of Myasthenia Gravis Patients

Abstract

<b><i>Objectives:</i></b> to investigate the expression levels of 1,25(OH)₂D₃ in the peripheral blood from patients with myasthenia gravis (MG) and to correlate levels with retinoid-related orphan receptor γt (RORγt) and forkhead or winged-helix transcription factor 3 (Foxp3) mRNA expression. <b><i>Methods:</i></b> Sixty-seven patients with MG were enrolled in the experimental group, and 50 normal subjects were selected as the control group. The expression levels of 1,25(OH)₂D₃ and RORγt and Foxp3 mRNAs were measured in the serum of the 2 patient groups and the relationship between factors were correlated with the severity score of MG. The relationship between the levels of 1,25(OH)₂D₃ and the relative expressions of RORγt and Foxp3 mRNAs was determined. <b><i>Results:</i></b> There were no differences between groups regarding patient’s baseline data. 1,25(OH)₂D₃ and RORγt and Foxp3 mRNAs are differentially expressed in the MG group and the control group (<i>p</i> &#x3c; 0.05). QMG score is negatively correlated with the expression level of peripheral blood 1,25(OH)₂D₃ and Foxp3 mRNA (<i>r</i> = −0.797, −0.543; <i>p</i> &#x3c; 0.01) and positively correlated with the relative expression level of RORγt mRNA (<i>r</i> = 0.539; <i>p</i> &#x3c; 0.01). 1,25(OH)₂D₃ expression level was negatively correlated with the relative expression of RORγt mRNA (<i>r</i> = −0.559; <i>p</i> &#x3c; 0.01) and positively correlated with the relative expression of Foxp3 mRNA (<i>r</i> = 0.390; <i>p</i> &#x3c; 0.01). <b><i>Conclusions:</i></b> The levels of 1,25(OH)₂D₃ were shown to be lower in patients with MG compared to normal controls. The observed low levels of 1,25(OH)₂D₃ may lead to changes in the expression of RORγt and Foxp3 mRNAs involved in MG.