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Updated: May 15, 2026
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In Vivo Imaging of Transduction Efficiencies of Cardiac Targeting Peptide
Published on: June 11, 2020
pH (low) insertion peptide (pHLIP) targets ischemic myocardium.
Eugene A Sosunov1, Evgeny P Anyukhovsky, Alexander A Sosunov
1Department of Pharmacology, Columbia University, New York, NY 10032, USA.
Summary
pH (low) insertion peptide (pHLIP) targets ischemic myocardium, offering a new diagnostic and therapeutic approach. This pH-sensitive peptide binds to affected heart tissue without causing damage, enabling targeted drug delivery.
Area of Science:
- Biomedical Engineering
- Cardiovascular Research
- Molecular Targeting
Background:
- The pH (low) insertion peptide (pHLIP) family is known for targeting cells in low extracellular pH environments.
- Ischemic conditions, such as in myocardial ischemia, create localized regions of low pH.
- Developing targeted strategies for ischemic tissues is crucial for effective diagnosis and therapy.
Purpose of the Study:
- To investigate the potential of pHLIPs for targeting ischemic myocardium.
- To evaluate the specificity and efficacy of pHLIPs in targeting regions of myocardial ischemia.
- To explore the feasibility of using pHLIPs for diagnostic or therapeutic agent delivery to ischemic heart tissue.
Main Methods:
- Utilized two murine ischemia models: regional ischemia (coronary artery occlusion) and global low-flow ischemia.
- Administered pH-sensitive pHLIPs (wild type and Var7) and pH-insensitive variants (kVar7).
- Employed pHLIP-coated liposomes and PEG-coated liposomes as controls.
Main Results:
- pH-sensitive pHLIPs and pHLIP-coated liposomes specifically bound to ischemic myocardium but not to normal tissue.
- pH-insensitive variants and PEG-coated liposomes showed no preferential binding.
- pHLIP application did not adversely affect the mechanical or electrical activity of the ischemic myocardium.
Conclusions:
- pHLIPs demonstrate specific targeting of ischemic myocardium, even in cases without severe tissue damage.
- This pH-sensitive targeting mechanism offers a novel route for delivering diagnostic probes or therapeutic agents to compromised heart regions.
- pHLIP-based strategies hold promise for managing conditions involving transient myocardial blood supply restrictions.
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