Hashimoto thyroiditis in Lebanon: Fibrinogen levels increase and redox homeostasis alteration in euthyroid patients and detection of a new SAA1 “ε” isoform (V52-V57)

• Published in: Gene reports Vol. 24; p. 101288
• Main Authors: Ibrahim, José-Noel, Chaib, Alexandre, Sawan, Dania, Bou Saab, Rita, Hanna, Johnny, Jounblat, Rania, Medlej-Hashim, Myrna
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.09.2021
• Subjects: Acute phase reactants; Hashimoto thyroiditis; IL1B; IL1RN; Oxidative stress; SAA1; CRP; Anti-TPO; Oxidative stress; IL1RN; Anti-Tg; MDA; H2O2; HT; Acute phase reactants; SAA; MBL; Hashimoto thyroiditis; IL1B; CAT; ROS; SAA1; VNTR; ELISA
• ISSN: 2452-0144; 2452-0144
• DOI: 10.1016/j.genrep.2021.101288

Hashimoto's thyroiditis (HT), the most common cause of hypothyroidism, is a multifactorial autoimmune condition characterized by elevated levels of anti-thyroid peroxidase (anti-TPO) and/or anti-thyroglobulin (anti-Tg), and involving both environmental and genetic factors. This study was designed to evaluate the levels of acute phase reactants and the oxidant/antioxidant status among Lebanese HT patients. It also aims to assess the possible association between selected polymorphisms of three genes, Serum amyloid A1 (SAA1), Interleukin 1 beta (IL1B) and Interleukin 1 receptor antagonist (IL1RN), and the occurrence of the disease. The study included 21 patients diagnosed with HT and 22 healthy controls. Fibrinogen, SAA, mannose binging lectin (MBL), C-reactive protein (CRP) and IL1B levels were analyzed by enzyme-linked immunosorbent assay (ELISA). The lipid peroxidation marker malondialdehyde (MDA) and the antioxidant enzyme catalase were assessed using assay kits. SAA1 (+2995C>T and +3010C>T) and IL1B polymorphisms (g. –511C>T, g. –31T>C and g. +3954C>T) were assessed by polymerase chain reaction (PCR)-digestion. The IL1RN 86 bp variable number of tandem repeats (VNTR) was identified by fragment-size analysis. Fibrinogen levels were significantly higher in HT patients than controls (p < 0.0001), unlike other inflammatory markers which showed comparable levels between both groups. IL1B levels were not detected in plasma of patients and controls. An increase in MDA levels (p < 0.0001) coupled with a decrease in catalase activity (p = 0.034) were observed in the patients' group as compared to controls. No significant association was found between the alleles and genotypes of the studied polymorphisms and the occurrence of the disease. Interestingly, a new SAA1 allele, assigned as “ε”, was observed in two Lebanese HT patients. Our results suggest an ongoing subclinical inflammation and an alteration of the redox homeostasis in HT patients. •Fibrinogen levels were increased and redox homeostasis altered in euthyroid patients.•A new SAA1 “ε”isoform (V52-V57) was detected in HT patients.•SAA1 β allele was associated with lower SAA levels in HT patients.