AB0051 Monocytes from Patients with Rheumatoid Arthritis and Type 2 Diabetes Mellitus Display an Increased Production of IL-1β Via the NLRP3-Inflammasome Activation. A Possible Implication for Therapeutic Decision in These Patients. (9th June 2015)

• Record Type: Journal Article
• Authors: Ruscitti, P.; Di Benedetto, P.; Cipriani, P.; Liakouli, V.; Berardicurti, O.; Carubbi, F.; Alvaro, S.; Giacomelli, R.
• Is Part Of: Annals of the rheumatic diseases. Volume 74(2015)Supplement 2
• Page Start: 907
• Page End: 907
• Publication Date: 2015-06-09
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2015-eular.3476
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: A better understanding about the mechanisms involved in the pathogenesis of type 2 diabetes mellitus (T2DM) showed that inflammatory cytokines such as tumor TNF-α and IL-1β play a pivotal role, mirroring data largely reported in rheumatoid arthritis (RA) [1]. Both preclinical and clinical studies confirmed the usefulness of IL-1β antagonism therapy in both diseases [2]. IL-1β is mainly produced by monocytes/macrophages. Hyperglycaemia may be able to modulate, in the cytoplasm of these cells, the assembly of a cytosolic multiprotein platforms, composed by 3 molecules: NLRP3 sensor protein; ASC adaptor protein; caspase-1, the so called NLRP3-inflammasome, where, the inactive pro-IL-1β is cleaved into active form, via caspase-1 activity [3]. Objectives: We evaluated the production of IL-1 β and TNF-α, in peripheral blood monocytes (MO) of patients affected by RA or T2DM or both diseases, in order to understand if, an alteration of the glucose metabolism may influence their pro-inflammatory status. Methods: We enrolled 10 RA patients, 10 T2DM patients and 10 patients affected by both the diseases (T2DM/RA patients), and 5 healthy controls (HC). From these patients, MO were isolated from human peripheral blood mononuclear cells using CD14 selection. After that MO were incubated with 11 mmol/1 glucose (11G) and 33 mmol/1 glucose (33G), for 24 hours, and we evaluated by ELISA the concentration of both IL-1β and TNF-α released in cultured MO supernatants, the relative mRNA expression by qRT-PCR and the western blot analysis of NLRP3. Due to the non parametric distribution of our data the Mann-Whitney U test was used as appropriate for analyses. Statistical significance was expressed by a p value <0.05. Results: Our data showed, after 24 hours of incubation with 11G, a significantly increase of IL-1β in supernatants of T2DM, RA, and T2DM/RA cultured MO, when compared with HC (p<0.01 for each comparison). Our data showed that after 24 hours of incubation with 33G a significant increase of IL-1β secretion by T2DM/RA MO of patients when compared with other groups (p<0.01 for each comparison). We observed after 24 hours of incubation with both 11G and 33G an increase of TNF-α in supernatants, in all groups when compared with HC (p<0.01 for each comparison). We did not observed significant differences in TNF-α secretion among T2DM, RA and T2DM/RA patients. The analysis of relative mRNA expression confirmed these data. Our results showed after 24 hours of incubation with both 11G and 33G a significant increase in relative NLRP3 mRNA expression when we compared T2DM/RA patients and the other groups (p<0.001 for each comparison). The results of western blot analyses for NLRP3 mirrored these data. Conclusions: Our study showed an increased production of IL-1β by MO obtained from patients affected by both RA and T2DM via NLRP3-inflammasome activation suggesting a potential IL-1β target therapy. References: Donath MY, et al. Type 2 diabetes as an inflammatory disease. Nat Rev Immunol. 2011;11:98-107. Eguchi K, et al. Macrophages and islet inflammation in type 2 diabetes. Diabetes Obes Metab. 2013;3:152-158. Schroder K, et al. The NLRP3 inflammasome: a sensor for metabolic danger? Science. 2010;327:296-300. Disclosure of Interest: None declared