THU0229 HSA-MIR-513C-3P OVEREXPRESSION DECREASES XBP-1S CORRELATING WITH INCREASED INFLAMMATION AND AUTOANTIBODIES IN SALIVARY GLANDS FROM SJÖGREN’S SYNDROME PATIENTS

Background: The approach from the point of view of the evolutionary perspective of finding targets for therapeutic effects among the components of the cellular destruction system is critical both in the treatment of rheumatological diseases and in gerontology. Objectives: To identify the relationships between the pathways of cell death in synovial fluid (SF) of people of different age groups with SDCT. Methods: SF was analyzed in patients of two age groups. Group N 1 of patients: 10 SLE (43±2.3 years), 13 RA (45±1.6 years), 7 SSD (35±1.8 years) and 8 donors (42±2.7 years, postmortem). Group N 2 (age) of patients: 9 SLE (69±1.8 years), 10 RA (65±1.6 years), 5 SSD (65±0.7 years) and 9 donors (66±2.3 years, postmortem). SF treated with 0.1% Triton-x-100, resuspended in 0.1% citrate buffer (pH = 7.4) and centrifuged at 25000 g for 30 minutes. The supernatant has been used in the experiment. The activity of adenosine monophosphate-activated protein kinase (AMPK) was evaluated by Western blotting. The level of p53 protein was analyzed by the enzyme immunoassay method using ELISA kit (eBioscience, (USA). The content of 8-hydroxy-2-deoxyguanosine (8-OH-dG) was evaluated using the EIA Kit (USA). Quantitative determination of cytochrome C (Cyt c) was carried using the ELISA kit. Active forms of oxygen free radicals (АFRF) were registered by EPR. Results: An interaction was established between the pathways of cell death in SDCT (mostly distinctive in SLE), age-related changes and clinical manifestations of the autoimmune process were established. The severity of cell death types depends on the nosological form of SDCT (tab.1). Autophagy (especially in the case of SLE, as well as RA) is directly involved in the formation of the immune response and the inflammatory process. During aging, as well as during SDCT, there is a sharp increase in the activity of AMPK (intracellular energy sensor), expression of apoptosis inductors increases and also the acid-base balance shifts, the number of active forms of oxygen radicals increases, ox-red changes, the components of cellular destruction are activated, the activity of the cytokine system of the organism is disturbed (cytokines - regulators of apoptosis), the expression of chaperones decreases and immuno-oxygenase homeostasis shifts. Inhibition of the genetically determined process of cell death, apoptosis, underlies the development of autoimmune diseases, immunepro-liferative pathology (carcinogenesis) and gerontological changes. Conclusion: The chaperone-mediated induction of the immune response as a signaling mechanism of autophagy, supposedly, is a common central link and a molecular switch that causes both the development of autoimmune diseases of connective tissue and geron-tological processes. References: [1]Shishkin V. I. et al. Ann Rheum Dis 2018; 77: sup.2 – А1274 Disclosure of Interests: None declared