TY - JOUR

T1 - A20 Inhibits β-Cell Apoptosis by Multiple Mechanisms and Predicts Residual β-Cell Function in Type 1 Diabetes

AU - Fukaya, Makiko

AU - Brorsson, Caroline A

AU - Meyerovich, Kira

AU - Catrysse, Leen

AU - Delaroche, Diane

AU - Vanzela, Emerielle C

AU - Ortis, Fernanda

AU - Beyaert, Rudi

AU - Nielsen, Lotte B

AU - Andersen, Marie L M

AU - Mortensen, Henrik B

AU - Pociot, Flemming

AU - van Loo, Geert

AU - Størling, Joachim

AU - Cardozo, Alessandra K

PY - 2016/1

Y1 - 2016/1

N2 - Activation of the transcription factor nuclear factor kappa B (NFkB) contributes to β-cell death in type 1 diabetes (T1D). Genome-wide association studies have identified the gene TNF-induced protein 3 (TNFAIP3), encoding for the zinc finger protein A20, as a susceptibility locus for T1D. A20 restricts NF-κB signaling and has strong antiapoptotic activities in β-cells. Although the role of A20 on NF-κB inhibition is well characterized, its other antiapoptotic functions are largely unknown. By studying INS-1E cells and rat dispersed islet cells knocked down or overexpressing A20 and islets isolated from the β-cell-specific A20 knockout mice, we presently demonstrate that A20 has broader effects in β-cells that are not restricted to inhibition of NF-κB. These involves, suppression of the proapoptotic mitogen-activated protein kinase c-Jun N-terminal kinase (JNK), activation of survival signaling via v-akt murine thymoma viral oncogene homolog (Akt) and consequently inhibition of the intrinsic apoptotic pathway. Finally, in a cohort of T1D children, we observed that the risk allele of the rs2327832 single nucleotide polymorphism of TNFAIP3 predicted lower C-peptide and higher hemoglobin A1c (HbA1c) levels 12 months after disease onset, indicating reduced residual β-cell function and impaired glycemic control. In conclusion, our results indicate a critical role for A20 in the regulation of β-cell survival and unveil novel mechanisms by which A20 controls β-cell fate. Moreover, we identify the single nucleotide polymorphism rs2327832 of TNFAIP3 as a possible prognostic marker for diabetes outcome in children with T1D.

AB - Activation of the transcription factor nuclear factor kappa B (NFkB) contributes to β-cell death in type 1 diabetes (T1D). Genome-wide association studies have identified the gene TNF-induced protein 3 (TNFAIP3), encoding for the zinc finger protein A20, as a susceptibility locus for T1D. A20 restricts NF-κB signaling and has strong antiapoptotic activities in β-cells. Although the role of A20 on NF-κB inhibition is well characterized, its other antiapoptotic functions are largely unknown. By studying INS-1E cells and rat dispersed islet cells knocked down or overexpressing A20 and islets isolated from the β-cell-specific A20 knockout mice, we presently demonstrate that A20 has broader effects in β-cells that are not restricted to inhibition of NF-κB. These involves, suppression of the proapoptotic mitogen-activated protein kinase c-Jun N-terminal kinase (JNK), activation of survival signaling via v-akt murine thymoma viral oncogene homolog (Akt) and consequently inhibition of the intrinsic apoptotic pathway. Finally, in a cohort of T1D children, we observed that the risk allele of the rs2327832 single nucleotide polymorphism of TNFAIP3 predicted lower C-peptide and higher hemoglobin A1c (HbA1c) levels 12 months after disease onset, indicating reduced residual β-cell function and impaired glycemic control. In conclusion, our results indicate a critical role for A20 in the regulation of β-cell survival and unveil novel mechanisms by which A20 controls β-cell fate. Moreover, we identify the single nucleotide polymorphism rs2327832 of TNFAIP3 as a possible prognostic marker for diabetes outcome in children with T1D.

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1210/me.2015-1176

DO - 10.1210/me.2015-1176

M3 - Journal article

C2 - 26652732

VL - 30

SP - 48

EP - 61

JO - Molecular Endocrinology

JF - Molecular Endocrinology

SN - 0888-8809

IS - 1

ER -