Interferon alpha gene expression and serum level association with low vitamin D levels in Egyptian female patients with systemic lupus erythematosus.

Background Patients with systemic lupus erythematosus (SLE) are prone to develop vitamin D (25(OH) D3) deficiency, due to several factors and there is an association between lower vitamin D levels and higher SLE disease activity. The aim of this research was to assess the prevalence of vitamin D deficiency in Egyptian female patients with SLE. Furthermore, we analyzed the potential relationship between this deficiency and SLE manifestations, disease activity, and its effect on interferon alpha (IFN-α) gene expression and serum level. Methods We evaluated the serum levels of vitamin D 25(OH)D3 and IFN-α by enzyme-linked immunosorbent assay (ELISA). IFN-α gene expression was measured by real-time polymerase chain reaction (PCR) assay in 123 Egyptian female patients with SLE and in 100 females as a healthy control group. Results Vitamin D deficiency was prevalent in 20.30%, while insufficiency was prevalent in 42.40% of the total group of patients. Serum levels of 25(OH)D3 were significantly decreased in the group of severe disease, and in the group of patients with lupus nephritis. 25(OH)D3 showed highly significant negative correlation with the SLE Disease Activity Index (SLEDAI) in the high activity group and lupus nephritis group. There was a significant negative correlation between 25(OH)D3 and IFN-α serum level and gene expression in all patients; more significant in the group with lupus nephritis. Conclusions The deficiency of 25(OH)D3 has a direct relationship with increase disease activity and nephritis in Egyptian SLE patients, suggesting the need for vitamin D supplementation in these patients. Also, it is directly correlated with increased secretion and gene expression of IFN-α, suggesting its role in pathogenesis of lupus nephritis, to be confirmed by further longitudinal observational studies.

Polymorphism in vitamin D receptor and osteoprotegerin genes in Egyptian rheumatoid arthritis patients with and without osteoporosis.

1α,25-Dihydroxyvitamin D3 upregulates the expression of the receptor activator of nuclear factor kB ligand (RANKL), and downregulates osteoprotegerin (OPG) expression. We tested the effects of polymorphisms in the vitamin D receptor gene (VDR), and OPG gene in rheumatoid arthritis (RA) patients and healthy controls and their relationship to bone mineral density (BMD) and development of osteoporosis. Three hundred and fifty women were evaluated, 200 women having RA and 150 healthy control. The subjects were genotyped for polymorphism at BsmI in VDR and A163G in OPG genes by polymerase chain reaction followed by restriction fragment length polymorphism analysis. BMD was also measured. In A163G, the G allele increased the risk for RA and for the development of osteoporosis. We found a significant association between lower hip (BMD-h) and genotype variants of VDR (BsmI) and OPG A163G in RA patients with osteoporosis. Our results suggested that OPG A163G polymorphism was associated with RA susceptibility and with the development of osteoporosis in these patients. Also, VDR and OPG genes are important candidates for osteoporosis in RA patients.