CPR: cardiac phosphatase in resuscitation

Area of Science:

• Cardiovascular Research
• Neuroscience
• Pharmacology

Background:

• Out-of-hospital cardiac arrest (OHCA) has a high mortality rate and poor long-term survival.
• A significant knowledge gap exists in identifying pharmacological interventions to improve neurological function and survival post-cardiac arrest.

Purpose of the Study:

• To engineer a novel peptide-based therapeutic to enhance neurological function and survival after cardiac arrest.
• To investigate the mechanism of action of the engineered peptide in preserving cellular function post-arrest.

Main Methods:

• Engineering of a 20-amino acid cell-permeable peptide (TAT-PHLPP9c) designed to antagonize PH domain leucine-rich repeat-containing phosphatase 1 (PHLPP1).
• Administration of TAT-PHLPP9c in murine and porcine models of cardiac arrest.
• Assessment of AKT pathway activation, cardiac output, cerebral blood flow, ATP levels, neurological outcomes, and survival rates.

Main Results:

• TAT-PHLPP9c successfully antagonized PHLPP1, preventing PHLPP1-mediated dephosphorylation and inactivation of AKT.
• Administration of TAT-PHLPP9c maintained activated AKT, leading to improved cardiac output, cerebral blood flow, and restored ATP levels.
• The peptide treatment resulted in significantly improved neurological outcomes and increased survival rates in both murine and porcine cardiac arrest models.

Conclusions:

• Pharmacological targeting of PHLPP1 using TAT-PHLPP9c is a promising strategy for improving outcomes after cardiac arrest.
• Maintaining AKT activation via PHLPP1 antagonism offers a potential therapeutic approach to enhance long-term survival and neurological recovery post-cardiac arrest.