Effect of ghrelin on aldolase gene expression in the heart of chronic hypoxic rat

Int J Endocrinol Metab. 2012 Summer;10(3):553-7. doi: 10.5812/ijem.3914. Epub 2012 Jun 30.

Abstract

Background: Chronic hypoxia causes apoptosis of cardiac myocytes, however, energy production by anaerobic glycolysis protects myocardium against hypoxia injuries. Aldolase A is a well-characterised key enzyme of the glycolysis pathway. Ghrelin, a 28-amino-acid peptide, synthesizes in the stomach and has protective roles in cardiovascular systems and also affects metabolic pathways.

Objectives: Therefore, the aim of this study was to evaluate the effect of ghrelin on aldolase A gene expression after chronic hypoxia in the rat hearts.

Materials and methods: Twenty four adult male wistar rats were randomly divided into three groups. Hypoxic rats with saline or ghrelin treatment were placed in a normobaric hypoxic chamber (O2 11 %), for two weeks. Controls remained in room air. Aldolase A gene expression was measured by Real-Time RT-PCR.

Results: the transcriptiom rate of Aldolase A in hypoxic animals did not change significantly compared to negative control ones. During chronic hypoxia, ghrelin treatment increased the amount of heart Aldolase A gene expression compared to negative controls (P = 0.029). Hypoxic animals that were treated with ghrelin were significantly more polycythemic than the controls and even hypoxic with saline treated rats (P < 0.001).

Conclusions: It seems that ghrelin interferes in the cardiac metabolism through upregulation of glycolytic enzymes. In other words, it may protect heart from possible hypoxia induced damages.

Keywords: Cell Hypoxia; Ghrelin; Glycolytic enzymes; Heart; Rat.