Research Article IL-1β gene polymorphism and serum levels in a Tunisian population with acute heart failure Trabelsi Imen *,1,2 , Messous Salma 1 , Chehaibi Khouloud 2 , Grissa Mohammed Habib 3 , Beltaief Kaouthar 3 , Tounsi Nejia 1 , Gannoun Imen 1 , Boubaker Hamdi 3 , Boukef Riadh 1 , Bouida Wahid 3 , Slimane Mohamed Naceur 2 & Nouira Semir 1,3 1 Research Laboratory (LR12SP18), University of Monastir, 5000 Monastir, Tunisia 2 ResearchUnit: UR 12ES09 Dyslipidemia & Atherogenesis, Faculty of Medicine, 5000 Monastir, Tunisia 3 Department of Emergency, Fattouma Bourguiba University Hospital, 5000 Monastir, Tunisia * Author for correspondence: imentrabelsi@hotmail.fr Aim: The aim of this study was to explore the relationship between IL-1β-31T/C polymorphism and serum levels of IL-1β and the risk of acute heart failure (AHF). Methods: A total of 320 dyspnea patients (160 with AHF and 160 without AHF) and 100 healthy subjects were included in this study. IL-1β genotyping was performed by PCR-restriction fragment length polymorphism technique. Results: Concentration of IL- 1β was significantly higher in patients with heart failure (HF) compared with non-HF and control groups. Results of the distribution of IL-1β-31T/C genotypes and allele frequencies did not show any significant difference between the three groups. Serum levels of IL-1β were found to be higher among TT genotype than TC and CC genotype. Conclusion: IL-1β levels may be useful for the evaluation of diagnosis in acutely decompensated HF. First draft submitted: 26 May 2017; Accepted for publication: 2 August 2017; Published online: 28 November 2017 Keywords: -31 T/C IL-1β polymorphism • acute heart failure • association • correlations • CRP • cytokine • diagnosis • IL-1β level • inflammation • NT pro-BNP • TT genotype Acute heart failure (AHF) is a major cause of morbidity [1] and a multisystem disorder which affects not only the cardiovascular system but also the musculoskeletal, renal, neuroendocrine and immune systems [2]. In 1955, the first data pointing the link between inflammation and the risk of heart failure (HF) were recorded, when a positive correlation was found between levels of C-reactive protein (CRP) and the severity of congestive HF [3,4]. The HF syndrome seems to be due to the variation of levels of inflammatory and anti-inflammatory mediators [4]. IL-1β is one of the most cytokines that are implicated in the pathogenesis of HF [4]. It is synthesized as an inactive 31 KDa precursor [5]. This must be cleaved by a specific enzyme cysteine protease type IL-1β converting enzyme [6], to give the biologically active cytokine 17.5 KDa [7]. It is considered to be the conductor of the synthesis of peripheral and cerebral cytokines and plays an important role in inflammatory processes. Previous data suggested that IL-1 signaling has an essential role in HF by suppressing cardiac function, promoting myocardial hypertrophy and even inducing cardiomyocyte apoptosis [8,9]. It shows that elevated levels of IL-1β in patients with acute decompensation of HF contributes to the development of vascular damage and atherosclerosis by stimulating cell proliferation and differentiation and the release of matrix-degrading enzymes [10,11]. IL-1β is located in 70–110 kb region of chromosome 2q13–21, including seven exons and six introns. At least 20 SNPs were reported in the region of IL-1β. The IL-1β-31T/C substitution located in the TATA box motif in the promoter region of the gene IL-1β , which is a critical motif concerned with transcriptional efficiency, and the change from −31 T to −31 C [12]. This substitution causes the potential disruption and decrease in the expression of IL-1β protein [13,14] and affect the binding of several transcription factors [13,15] and thereby affecting the transcription activity of IL-1β [16]. Biomark. Med. (2017) 11(12), 1069–1076 ISSN 1752-0363 1069 10.2217/bmm-2017-0179 C  2017 Future Medicine Ltd