Phoenixin-14: detection and novel physiological implications in cardiac modulation and cardioprotection.
C RoccaF ScavelloM C GranieriT PasquaN AmodioS ImbrognoA GattusoR MazzaMaria Carmela CerraDomenico GabrielePublished in: Cellular and molecular life sciences : CMLS (2017)
Phoenixin-14 (PNX) is a newly identified peptide co-expressed in the hypothalamus with the anorexic and cardioactive Nesfatin-1. Like Nesfatin-1, PNX is able to cross the blood-brain barrier and this suggests a role in peripheral modulation. Preliminary mass spectrography data indicate that, in addition to the hypothalamus, PNX is present in the mammalian heart. This study aimed to quantify PNX expression in the rat heart, and to evaluate whether the peptide influences the myocardial function under basal condition and in the presence of ischemia/reperfusion (I/R). By ELISA the presence of PNX was detected in both hypothalamus and heart. In plasma of normal, but not of obese rats, the peptide concentrations increased after meal. Exposure of the isolated and Langendorff perfused rat heart to exogenous PNX induces a reduction of contractility and relaxation, without effects on coronary pressure and heart rate. As revealed by immunoblotting, these effects were accompanied by an increase of Erk1/2, Akt and eNOS phosphorylation. PNX (EC50 dose), administered after ischemia, induced post-conditioning-like cardioprotection. This was revealed by a smaller infarct size and a better systolic recovery with respect to those detected on hearts exposed to I/R alone. The peptide also activates the cardioprotective RISK and SAFE cascades and inhibits apoptosis. These effects were also observed in the heart of obese rats. Our data provide a first evidence on the peripheral activity of PNX and on its direct cardiomodulatory and cardioprotective role under both normal conditions and in the presence of metabolic disorders.
Keyphrases
- heart failure
- heart rate
- blood pressure
- left ventricular
- oxidative stress
- atrial fibrillation
- metabolic syndrome
- adipose tissue
- signaling pathway
- cell proliferation
- heart rate variability
- weight loss
- poor prognosis
- electronic health record
- nitric oxide
- big data
- coronary artery disease
- endoplasmic reticulum stress
- machine learning
- diabetic rats
- loop mediated isothermal amplification
- protein kinase
- acute coronary syndrome
- percutaneous coronary intervention
- quantum dots
- stress induced