Background:
Metabolic syndrome (MetS) is a combination of metabolic disorders with
increased risks for several diseases, such as cardiovascular diseases and diabetes. It is associated with
the presence of various inflammatory molecules. Vitamin D plays an important role in the regulation of
metabolism homeostasis.
Objective:
The main goal of this work is to investigate vitamin D levels among Algerian MetS patients
and its possible outcomes on key molecules of the immune response, as well, the immunomodulatory
effects of its active metabolite.
Methods:
We evaluated vitamin D status by the electrochemiluminescence method, Nitric Oxide (NO)
levels by the Griess method and Matrix Metalloproteinases (MMPs) activities such as MMP-2 and
MMP-9 by zymography in plasma of patients and healthy controls (HC). The immunomodulatory effects
of the active metabolite of vitamin D (α-25 (OH)2D3) on the production of NO, IL-6, IL-10, TGF-
β and s-CTLA-4 were assessed by Griess method and ELISA, in peripheral blood mononuclear cells
(PBMCs) of Algerian MetS patients and HC. MMPs activities were also determined ex-vivo, while
iNOS expression was assessed by immunofluorescence staining.
Results:
Severe vitamin D deficiency was registered in Algerian MetS patients. The deficiency was
found to be associated with an elevated in vivo NO production and high MMPs activity. Interestingly,
α-25 (OH)2D3 declined the NO/iNOS system and IL-6 production, as well as MMPs activities. However,
the ex-vivo production of IL-10, TGF-β increased in response to the treatment. We observed in
the same way, the implication of s-CTLA-4 in MetS, which was markedly up-regulated with α-25
(OH)2D3.
Conclusion:
Our report indicated the relationship between MetS factors and Vitamin D deficiency.
The ex-vivo findings emphasize its impact on maintaining regulated immune balance.
Vitamin D analogues: how do they differ and what is their clinical role?