Ulster University Logo

Ulster Institutional Repository

L-Arginine is essential for pancreatic beta-cell functional integrity, metabolism and defense from inflammatory challenge

Biomedical Sciences Research Institute Computer Science Research Institute Environmental Sciences Research Institute Nanotechnology & Advanced Materials Research Institute

Krause, MS, McClenaghan, Neville, Flatt, Peter, de Bittencourt, PIH, Murphy, C and Newsholme, P (2011) L-Arginine is essential for pancreatic beta-cell functional integrity, metabolism and defense from inflammatory challenge. JOURNAL OF ENDOCRINOLOGY, 211 (1). pp. 87-97. [Journal article]

Full text not available from this repository.

DOI: 10.1530/JOE-11-0236

Abstract

In this work, our aim was to determine whether L-arginine (a known insulinotropic amino acid) can promote a shift of beta-cell intermediary metabolism favoring glutathione (GSH) and glutathione disulfide (GSSG) antioxidant responses, stimulus-secretion coupling and functional integrity. Clonal BRIN-BD11 beta-cells and mouse islets were cultured for 24 h at various L-arginine concentrations (0-1.15 mmol/l) in the absence or presence of a proinflammatory cytokine cocktail (interleukin 1 beta, tumour necrosis factor a and interferon gamma). Cells were assessed for viability, insulin secretion, GSH, GSSG, glutamate, nitric oxide (NO), superoxide, urea, lactate and for the consumption of glucose and glutamine. Protein levels of NO synthase-2, AMP-activated protein kinase (AMPK) and the heat shock protein 72 (HSP72) were also evaluated. We found that L-arginine at 1.15 mmol/l attenuated the loss of beta-cell viability observed in the presence of proinflammatory cytokines. L-Arginine increased total cellular GSH and glutamate levels but reduced the GSSG/GSH ratio and glutamate release. The amino acid stimulated glucose consumption in the presence of cytokines while also stimulating AMPK phosphorylation and HSP72 expression. Proinflammatory cytokines reduced, by at least 50%, chronic (24 h) insulin secretion, an effect partially attenuated by L-arginine. Acute insulin secretion was robustly stimulated by L-arginine but this effect was abolished in the presence of cytokines. We conclude that L-arginine can stimulate beta-cell insulin secretion, antioxidant and protective responses, enabling increased functional integrity of beta-cells and islets in the presence of proinflammatory cytokines. Glucose consumption and intermediary metabolism were increased by L-arginine. These results highlight the importance of L-arginine availability for beta-cells during inflammatory challenge. Journal of Endocrinology (2011) 211, 87-97

Item Type:Journal article
Faculties and Schools:Faculty of Life and Health Sciences
Faculty of Life and Health Sciences > School of Biomedical Sciences
Research Institutes and Groups:Biomedical Sciences Research Institute
Biomedical Sciences Research Institute > Diabetes
ID Code:20370
Deposited By:Dr Nigel Irwin
Deposited On:28 Oct 2011 12:17
Last Modified:28 Oct 2011 12:17

Repository Staff Only: item control page