Serum levels of matrix metalloproteinase-2, -9, and vitamin D in patients with multiple sclerosis with or without herpesvirus-6 seropositivity

ABSTRACT In recent years, extreme attention has been focused on the role of human herpesvirus-6 (HHV-6) in multiple sclerosis (MS) pathogenesis. However, the pathogenesis of MS associated with HHV-6 infection remains unknown. In this study, we measured the serum levels of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), and vitamin D levels in MS patients with HHV-6 infection and MS patients without HHV-6 infection. Five hundred sixty (including 300 females and 260 males) MS patients along with 560 healthy subjects were analyzed for HHV-6 seropositivity using enzyme-linked immunosorbent assay (ELISA). Subsequently, we measured the serum levels of MMP-2, MMP-9, and vitamin D levels in MS patients with HHV-6 infection and MS patients without HHV-6 infection by ELISA. About 90.7% of MS patients (508/560) were seropositive for HHV-6, while 82.3% (461/560) of healthy subjects were seropositive for this virus (p = 0.001). Moreover, there was a significant increase in the levels of MMP-2, MMP-9, and lower vitamin D in the serum samples of MS patients when compared with healthy subjects. Additionally, we demonstrated that the MMP-9 levels in seropositive MS patients were significantly higher than seronegative MS patients (p = 0.001). Finally, our results demonstrated that the mean of expanded disability status scale (EDSS) in seropositive MS patients was significantly higher in comparison to seronegative MS patients (p < 0.05). In conclusion, we suggest that the HHV-6 infection may play a role in MS pathogenesis.

Quantifying Environmental Risk Factors for Multiple Sclerosis in Discordant Monozygotic Twins: A Case Report.

Relative contribution of genetic and environmental risk factors in complex disorders is widely explored through discordant identical twins. Multiple sclerosis is a demyelinating disease of the central nervous system in which the interplay of genetic and environmental risk factors define the disease pathogenicity. Robust epidemiological studies in different populations suggested that active levels of serum vitamin D and viral load implicate in MS pathogenicity and severity. In order to refine non-shared components of susceptibility factors in MS, we investigated the role of serum 25-hydroxyvitamin D and viral infection in a pair of identical twins remained discordant for MS during the course of 5 years follow up. Here we report serological finding regarding the viral load and serum 25-hydroxyvitamin D level in a pair of discordant monozygotic twins. Based on our observation, lower levels of serum 25-hydroxyvitamin D and higher anti-viral IgG titre was consistent with the disease statues in the affected sib.