Ankylosing Spondylitis (AS) is a chronic rheumatic disease that principally affects the intervertebral and sacroiliac joints. Two major features of AS are inflammation and bone reformation. Th17 cells as a new subpopulation of CD4+ T cells, are characterized by the production of pro-inflammatory cytokines. Th17 cells have been implicated in autoimmune diseases, pathogenesis and diagnosis of several inflammatory diseases, such as AS. Regulatory T cells (Treg) with suppressive effects on inflammation and autoimmunity have been reported to implicate in pathology of AS. The Treg /Th17 functional balance is essential for the prevention of autoimmune and inflammatory diseases by preventing deleterious impairment to the host and mounting effective immune responses. A group of circulating miRNA in plasma is found to be the change they can be involved in inflammation or inhibit it. miRNAs have been shown to play a pivotal role in the pathogenesis of various diseases including autoimmune or auto-inflammatory diseases.The function and molecular pathways of several key deregulated miRNAs, are elucidated in AS patients. Curcumin is an active component of turmeric which is a perennial plant. Curcumin is able to exert anti-atherogenic, anti-cancer and anti-inflammatory effects. The curcumin induces down-regulation of various inflammatory cytokines including TNF-α and IL-1. The solubility of curcumin in nanomicelles spherical water increases to more than 100 thousand times, which significantly enhances the absorption of curcumin. The aim of the present study was to understand the nano-curcumin effects on frequency of Treg and Th17 cells, expression levels of their associated transcription factors and cytokines, secretion levels of their associated cytokines and also related miRNAs expression levels in peripheral blood of patients with AS and their correlation with the disease progression.

A16-weeks randomized placebo-controlled study was conducted on a total of 24 patients with age range of 22 to 50, who were clinically diagnosed with ankylosing spondylitis on the basis of clinical manifestations. The AS patients were divided into 2 subgroup with a block randomization, 12 out of 24 received a daily dose of 80 mg oral nano-curcumin and 12 patients received placebo as control group in a period of 4 months. Peripheral blood samples (8 ml) were obtained from the patients in both control and treatment groups before and after nano-curcumin treatment for 4 months. PBMCs were isolated from samples using Ficoll separation technique. Subsequently, cells were cultured in the presence of PMA. Treg cells associated immunological parameters such as mRNA expression levels of mir-146a, mir-27 and mir-17, TGF-β, IL-10, IL-6 and FoxP3 and alsoTh17 related immunological parameters such as mRNA expression of mir-141, mir-155 and mir-200, IL-17, IL-23 and RORγt were measured by real-time PCR, also Treg and Th17 frequency and their related cytokines secretion levels were evaluated respectively by flowcytometry and ELISA technique in both groups, pre and post-treatment.

Inclusion Criteria:

• Willingness to cooperate
• Aged 22 to 50 years
• The diagnosis of ankylosing spondylitis by rheumatologist
• Patients with a BASDAI > 4 as having active disease.
• Disease duration 5-8 years

Exclusion Criteria:

• Nutritional supplements and antioxidant alpha-lipoic acid a month before the study.
• Pregnancy and lactation
• History of diabetes and other chronic diseases
• History of other autoimmune diseases
• Occurrence of relapses during the study period
• Acceptance rate of less than 70% of supplements
• Unwillingness to continue to cooperate