Coronary heart disease is characterized by atherosclerosis, which typically results in coronary stenosis and myocardial ischemia. Myocardial ischemia can appear as chronic ischemia without symptoms or acute ischemia with diverse symptoms. Variable studies have shown that adipokines, produced by adipose tissue, are involved in inflammatory processes. It has been shown that adipokines influence the development and progress of coronary heart diseases.
We investigate the expression of Leptin, Adiponectin and its receptors AdipoR-1 and AdipoR-2 in epicardial adipose tissue (EAT), mediastinal adipose tissue (MAT) and peripheral adipose tissue (PAT) of patients with coronary artery disease with different ischemic states.
EAT, MAT and PAT samples of patients undergoing cardiac surgery with chronic (CI; n=5), acute (AI; n=5) and non-ischemia (NI; n=5) were compared. Levels of Leptin, Adiponectin, AdipoR-1 and AdipoR-2 were determined by RT-PCR. Comparisons of the three groups were evaluated by one-way ANOVA. P<0.05 was considered statistically significant.
Comparing Adiponectin expression in PAT, MAT and EAT samples, a significant gradually increase from NI to CI in expression levels was detected in the PAT and MAT groups. Adiponectin levels significantly decreased gradually from PAT to EAT in CI patients. AdipoR-1 showed the reverse expression levels. Leptin expression levels were opposed detected to Adiponectin levels when comparing PAT, MAT and EAT within the NI, AI and CI groups.
Our results show a correlation between Adipokine, AdipoR-1 and Leptin expression in coronary artery disease with different stages of ischemia. Leptin, known to evoke pro-inflammatory effects, is up-regulated in CI tissue and EAT. On the other hand, Adiponectin, which is acting in a more anti-inflammatory way, is less found in AI tissue compared to CI tissue samples. Thus we suggest a regulatory relationship between Leptin and Adiponectin in ischemic inflammatory processes. Additionally, a reversed gradual expression of Adiponectin and Leptin was found in CI tissue samples.