PMID- 28261303 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20240324 IS - 1734-1922 (Print) IS - 1896-9151 (Electronic) IS - 1734-1922 (Linking) VI - 13 IP - 2 DP - 2017 Mar 1 TI - Stimulation of beta-adrenergic receptors plays a protective role via increased expression of RAF-1 and PDX-1 in hyperglycemic rat pancreatic islet (RIN-m5F) cells. PG - 470-480 LID - 10.5114/aoms.2016.64131 [doi] AB - INTRODUCTION: It is a widely held view that a progressive reduction of beta-cell mass occurs in the progression of diabetes. RAF-1 kinase and pancreas duodenal homeobox 1 (PDX-1) are major factors that promote survival of cells and maintain normal insulin functions. In this study we investigated the effect of a beta-adrenergic receptor agonist and antagonist on RAF-1 and PDX-1, and their respective effects on apoptosis and insulin release in RIN-m5F cells. MATERIAL AND METHODS: RIN-m5F cells were cultured in normal (5 mM) and high (25 mM) glucose to mimic diabetic conditions, followed by treatment with 5 microM, 10 microM and 20 microM of isoproterenol and isoproterenol + propranolol for 6, 12 and 24 h. Western blotting and reverse transcription analysis were performed to examine the expression of RAF-1 and PDX-1. Annexin-V-FITC and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assays were used to investigate apoptosis. ELISA was used to measure insulin levels. Reverse transcription polymerase chain reaction was conducted to investigate the expression of genes. RESULTS: Stimulation of beta-adrenergic receptors with isoproterenol significantly induced RAF-1 and PDX-1 genes in a concentration-dependent and time-independent manner. Changes were significant both at protein and mRNA levels. Up-regulation of RAF-1 and PDX-1 was accompanied by improved insulin levels and reduced apoptosis. Concentrations of 10 microM and 20 microM for 12 and 24 h were more effective in achieving significant differences in the experimental and control groups. Propranolol reversed the effect of isoproterenol mostly at maximum concentrations and time periods. CONCLUSIONS: A positive effect of a beta-adrenergic agonist on RAF-1 and PDX-1, reduction in beta-cell apoptosis and improved insulin contents can help to understand the pathogenesis of diabetes and to develop novel approaches for the beta-cell dysfunction in diabetes. FAU - Safi, Sher Zaman AU - Safi SZ AD - Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia; Interdisciplinary Research Center in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology, Lahore, Pakistan. FAU - Qvist, Rajes AU - Qvist R AD - Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. FAU - Ong, Gracie AU - Ong G AD - Department of Anesthesiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. FAU - Karimian, Hamed AU - Karimian H AD - Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. FAU - Imran, Muhammad AU - Imran M AD - Biochemistry Section, Institute of Chemical Sciences, University of Peshawar, Peshawar, Pakistan. FAU - Shah, Ikram AU - Shah I AD - Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia. LA - eng PT - Journal Article DEP - 20161205 PL - Poland TA - Arch Med Sci JT - Archives of medical science : AMS JID - 101258257 PMC - PMC5332455 OTO - NOTNLM OT - apoptosis OT - hyperglycemia OT - insulin OT - pancreas duodenal homeobox 1 OT - v-raf-leukemia viral oncogene 1 OT - beta-adrenergic receptors COIS- The authors declare no conflict of interest. EDAT- 2017/03/07 06:00 MHDA- 2017/03/07 06:01 PMCR- 2017/03/01 CRDT- 2017/03/07 06:00 PHST- 2014/12/05 00:00 [received] PHST- 2015/07/14 00:00 [accepted] PHST- 2017/03/07 06:00 [entrez] PHST- 2017/03/07 06:00 [pubmed] PHST- 2017/03/07 06:01 [medline] PHST- 2017/03/01 00:00 [pmc-release] AID - 28858 [pii] AID - 10.5114/aoms.2016.64131 [doi] PST - ppublish SO - Arch Med Sci. 2017 Mar 1;13(2):470-480. doi: 10.5114/aoms.2016.64131. Epub 2016 Dec 5.