Effect of insulin on natriuretic peptide gene expression in porcine heart.

Abstract

Gut hormones affect cardiac function and contractility. In this study, we examined whether insulin affects the cardiac atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) gene expression and release of proANP-derived peptides in pigs. Anaesthetized pigs were included in an experimental study comparing the effect of hyperinsulinemia in 15 pigs submitted to two different protocols versus 11 control pigs receiving saline infusion. Phosphorylation of Akt on Thr308 was determined by western blotting with a pAkt-Thr308 antibody. The mRNA contents of ANP and BNP were determined with real-time PCR; plasma and cardiac tissue proANP was measured with an immunoluminometric assay targeted against the mid-region of the propeptide and a processing-independent assay. Insulin stimulation increased phosphorylation of Akt Thr308 in both left atrium and left ventricle of porcine hearts (p < 0.005). No change was observed in ANP and BNP mRNA contents in the right or left atrium. BNP mRNA contents in the left ventricle, however, decreased 3-fold (p = 0.02) compared to control animals, whereas the BNP mRNA content in the right ventricle as well as ANP mRNA content in the right and left ventricle did not change following hyperinsulinemia. Moreover, the peptide contents did not change in the four cardiac chambers. Finally, proANP concentrations in plasma did not change during the insulin infusion compared to the control animals. These results suggest that insulin does not have direct effect on atrial natriuretic peptide expression but may have a role in the left ventricle.

• Authors: Dijana Terzic, Nora E Zois, Ingrid Hunter, Christina Christoffersen, Peter Plomgaard, Lisbeth Høier Olsen, Stine Ringholm, Henriette Pilegaard, Jens P Goetze
• Journal: Peptides (Peptides) Vol. 131 Pg. 170370 (09 2020) ISSN: 1873-5169 [Electronic] United States
• PMID: 32663503 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2020. Published by Elsevier Inc.

Chemical References

• Blood Glucose
• Insulin
• RNA, Messenger
• Natriuretic Peptide, Brain
• Atrial Natriuretic Factor
• Proto-Oncogene Proteins c-akt

Topics

• Animals
• Atrial Natriuretic Factor (genetics, metabolism)
• Blood Glucose (metabolism)
• Female
• Gene Expression Regulation
• Glucose Clamp Technique (methods)
• Heart Atria (drug effects, metabolism)
• Heart Ventricles (drug effects, metabolism)
• Hyperinsulinism (blood, chemically induced, genetics, veterinary)
• Infusions, Intravenous
• Insulin (administration & dosage)
• Natriuretic Peptide, Brain (genetics, metabolism)
• Phosphorylation (drug effects)
• Proto-Oncogene Proteins c-akt (genetics, metabolism)
• RNA, Messenger (genetics, metabolism)
• Swine