Defective lymphocyte caspase-3 expression in type 1 diabetes mellitus

• Published in: European journal of endocrinology Vol. 152; no. 1; pp. 119 - 125
• Main Authors: Vendrame, Francesco, Santangelo, Carmela, Misasi, Roberta, Dionisi, Sabrina, Gizzi, Chiara, Realacci, Massimo, Grassetti, Daniele, Di Mario, Umberto, Dotta, Francesco
• Format: Journal Article
• Language: English
• Published: Colchester European Society of Endocrinology 01.01.2005; Portland Press
• Subjects: Adolescent; Adult; Apoptosis - physiology; Biological and medical sciences; Caspase 3; Caspases - biosynthesis; Caspases - blood; Caspases - genetics; Child; Clinical Studies; Diabetes Mellitus, Type 1 - blood; Diabetes Mellitus, Type 1 - enzymology; Endocrinopathies; fas Receptor - biosynthesis; fas Receptor - blood; Female; Fundamental and applied biological sciences. Psychology; Humans; Immunoblotting; Lymphocyte Activation; Male; Medical sciences; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger - biosynthesis; RNA, Messenger - genetics; T-Lymphocytes - enzymology; Vertebrates: endocrinology; Endocrinopathy; Immunopathology; Peptidases; Enzyme; Type 1 diabetes; Cysteine endopeptidases; Deficiency; Hydrolases; Autoimmune disease; Lymphocyte; Endocrinology
• ISSN: 0804-4643; 1479-683X
• DOI: 10.1530/eje.1.01813

Objective: Activation-induced cell death (AICD) is a major mechanism in the regulation of peripheral tolerance and its impairment can determine the development of autoimmunity. In the present study, in order to evaluate the role of caspase-3 in type 1 diabetes mellitus (T1DM) AICD, caspase-3 expression was analyzed in peripheral blood lymphocytes from 37 new onset T1DM patients and from 36 normal control subjects (NC) in resting conditions and after anti-Fas-triggered apoptosis. Methods: Caspase-3 expression was determined by semiquantitative RT-PCR and Western blot. Apoptosis was induced in activated lymphocytes by anti-Fas monoclonal antibody and quantified by flow cytometry and morphological analysis. Results: Caspase-3 mRNA expression was reduced in resting lymphocytes in 18/37 T1DM patients and in 1/36 NC (P < 0.01). Patients studied for both Fas-mediated AICD and caspase-3 mRNA expression revealed that a reduced caspase-3 mRNA expression in resting lymphocytes occurred in all patients showing resistance to Fas-mediated apoptosis (T1DM vs NC, P < 0.02) with the exception of 3 patients who exhibited normal caspase-3 expression levels. Caspase-3 protein analysis confirmed mRNA data and showed an impaired expression of caspase-3 active form in T1DM subjects compared with NC. Conclusions: Our data show that defective expression and function of caspase-3 in peripheral lymphocytes of T1DM patients may contribute to the development of AICD resistance in type 1 diabetes.