Anti-Inflammatory & Anti-Allergy Agents in Medicinal ChemistryAnti-Inflammatory & Anti-Allergy Agents in Medicinal ChemistryAnti-Inflammatory & Anti-Allergy Agents in Medicinal Chemistry1871-52301875-614XBentham Science64466010.2174/0118715230293847240314073359MedicineResearch ArticleImmunoregulatory Effects of the Active Form of Vitamin D (Calcitriol), Individually and in Combination with Curcumin, on Peripheral Blood Mononuclear Cells (PBMCs) of Multiple Sclerosis (MS) PatientsFasihiMahdiehinfo@benthamscience.netSamimi-BadabiMahsainfo@benthamscience.netRobat-JaziBehrouzinfo@benthamscience.netBitarafanSamainfo@benthamscience.netMoghadasiAbdorrezainfo@benthamscience.netMansouriFatemehinfo@benthamscience.netYekaninejadMirinfo@benthamscience.netIzadMaryaminfo@benthamscience.netSaboor-YaraghiAliinfo@benthamscience.netDepartment of Immunology, School of Public Health, Tehran University of Medical SciencesIranian Center of Neurological Research, Department of Neurology, Imam Khomeini Hospital, Tehran University of Medical SciencesDepartment of Neurology and MS Research Center, Neuroscience Institute, Sina Hospital, Tehran University of Medical SciencesDepartment of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical SciencesDepartment of Immunology, School of Medicine, Tehran University of Medical Sciences0102202423213814707012025Copyright ©; 2024, Bentham Science Publishers2024Bentham Science Publishershttps://journals.eco-vector.com/1871-5230/article/view/644660

Objectives:Multiple sclerosis (MS) is a chronic autoimmune inflammatory disease affecting the central nervous system. Immune cell subsets, notably T helper (Th) 17 and Th1, exert important roles in MS pathogenesis. Whereas, Treg cells modulate the disease process. Calcitriol, the active form of vitamin D, and curcumin, a bioactive compound derived from turmeric, play immunomodulatory effects relevant to autoimmune disorders, including MS. The objective of this study is to investigate the effects of calcitriol and Curcumin on Peripheral blood mononuclear cells (PBMCs) of individuals with MS.

Methods:PBMCs from twenty MS patients were isolated, cultured, and exposed to 0.004 µg/mL of calcitriol and 10 µg/mL of curcumin. The cells underwent treatment with singular or combined doses of these components to assess potential cumulative or synergistic immunomod-ulatory effects. Following treatment, the expression levels of genes and the cellular population of Treg, Th1 and Th17 were evaluated using Real-time PCR and flow cytometry.

Results:Treatment with curcumin and calcitriol led to a significant reduction in the expression levels of inflammatory cytokines and transcription factors related to Th1 and Th17 cells, including IFN-γ, T-bet, IL-17, and RORC. Furthermore, the frequency of these cells decreased following treatment. Additionally, curcumin and calcitriol treatment resulted in a significant upregulation of the FOXP3 gene expression and an increase in the frequency of Treg cells.

Conclusion:This study demonstrates that curcumin and calcitriol can effectively modulate the inflammatory processes intrinsic to MS by mitigating the expression of inflammatory cytokines by Th1 and Th17 cells while concurrently enhancing the regulatory role of Treg cells. Moreover, the combined treatment of curcumin and calcitriol did not yield superior outcomes compared to single-dosing strategies.

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