» Articles » PMID: 21103982

Deletion of Protein Kinase Cδ in Mice Modulates Stability of Inflammatory Genes and Protects Against Cytokine-stimulated Beta Cell Death in Vitro and in Vivo

Overview
Journal Diabetologia
Specialty Endocrinology
Date 2010 Nov 25
PMID 21103982
Citations 22
Authors
Affiliations
Soon will be listed here.
Abstract

Aims/hypothesis: Proinflammatory cytokines contribute to beta cell destruction in type 1 diabetes, but the mechanisms are incompletely understood. The aim of the current study was to address the role of the protein kinase C (PKC) isoform PKCδ, a diverse regulator of cell death, in cytokine-stimulated apoptosis in primary beta cells.

Methods: Islets isolated from wild-type or Prkcd(-/-) mice were treated with IL-1β, TNF-α and IFNγ and assayed for apoptosis, nitric oxide (NO) generation and insulin secretion. Activation of signalling pathways, apoptosis and endoplasmic reticulum (ER) stress were determined by immunoblotting. Stabilisation of mRNA transcripts was measured by RT-PCR following transcriptional arrest. Mice were injected with multiple low doses of streptozotocin (MLD-STZ) and fasting blood glucose monitored.

Results: Deletion of Prkcd inhibited apoptosis and NO generation in islets stimulated ex vivo with cytokines. It also delayed the onset of hyperglycaemia in MLD-STZ-treated mice. Activation of ERK, p38, JNK, AKT1, the ER stress markers DDIT3 and phospho-EIF2α and the intrinsic apoptotic markers BCL2 and MCL1 was not different between genotypes. However, deletion of Prkcd destabilised mRNA transcripts for Nos2, and for multiple components of the toll-like receptor 2 (TLR2) signalling complex, which resulted in disrupted TLR2 signalling.

Conclusions/interpretation: Loss of PKCδ partially protects against hyperglycaemia in the MLD-STZ model in vivo, and against cytokine-mediated apoptosis in vitro. This is accompanied by reduced NO generation and destabilisation of Nos2 and components of the TLR2 signalling pathway. The results highlight a mechanism for regulating proinflammatory gene expression in beta cells independently of transcription.

Citing Articles

Regulatory roles of CARD9-BCL10-Rac1 (CBR) signalome in islet β-cell function in health and metabolic stress: Is there room for MALT1?.

Kowluru A Biochem Pharmacol. 2023; 218:115889.

PMID: 37991197 PMC: 10872519. DOI: 10.1016/j.bcp.2023.115889.


Regulatory Roles of Histone Deacetylation in Metabolic Stress-Induced Expression of Caspase Recruitment Domain-Containing Protein 9 (CARD9) in Pancreatic β-Cells.

Hali M, Pinto N, Gleason N, Kowluru A Int J Mol Sci. 2023; 24(21).

PMID: 37958977 PMC: 10647342. DOI: 10.3390/ijms242115994.


Islet cells in human type 1 diabetes: from recent advances to novel therapies - a symposium-based roadmap for future research.

Cantley J, Eizirik D, Latres E, Dayan C J Endocrinol. 2023; 259(1).

PMID: 37493471 PMC: 10502961. DOI: 10.1530/JOE-23-0082.


Bioactive lipids and metabolic syndrome-a symposium report.

DeVito L, Dennis E, Kahn B, Shulman G, Witztum J, Sadhu S Ann N Y Acad Sci. 2022; 1511(1):87-106.

PMID: 35218041 PMC: 9219555. DOI: 10.1111/nyas.14752.


Phenotype of a transient neonatal diabetes point mutation (SUR1-R1183W) in mice.

Sachse G, Haythorne E, Proks P, Stewart M, Cater H, Ellard S Wellcome Open Res. 2021; 5:15.

PMID: 34368464 PMC: 8323074. DOI: 10.12688/wellcomeopenres.15529.2.


References
1.
Van de Casteele M, Kefas B, Ling Z, Heimberg H, Pipeleers D . Specific expression of Bax-omega in pancreatic beta-cells is down-regulated by cytokines before the onset of apoptosis. Endocrinology. 2001; 143(1):320-6. DOI: 10.1210/endo.143.1.8574. View

2.
Kim H, Han M, Chung K, Kim S, Kim E, Kim M . Toll-like receptor 2 senses beta-cell death and contributes to the initiation of autoimmune diabetes. Immunity. 2007; 27(2):321-33. DOI: 10.1016/j.immuni.2007.06.010. View

3.
Stoecklin G, Anderson P . Posttranscriptional mechanisms regulating the inflammatory response. Adv Immunol. 2006; 89:1-37. DOI: 10.1016/S0065-2776(05)89001-7. View

4.
Carpenter L, Cordery D, Biden T . Protein kinase Cdelta activation by interleukin-1beta stabilizes inducible nitric-oxide synthase mRNA in pancreatic beta-cells. J Biol Chem. 2000; 276(7):5368-74. DOI: 10.1074/jbc.M010036200. View

5.
Uchida T, Iwashita N, Ohara-Imaizumi M, Ogihara T, Nagai S, Choi J . Protein kinase Cdelta plays a non-redundant role in insulin secretion in pancreatic beta cells. J Biol Chem. 2006; 282(4):2707-16. DOI: 10.1074/jbc.M610482200. View