Apolipoprotein M Attenuates Anthracycline Cardiotoxicity and Lysosomal Injury

Area of Science:

• Biochemistry
• Cardiology
• Molecular Biology

Background:

• Apolipoprotein M (ApoM) binds sphingosine-1-phosphate (S1P).
• ApoM is inversely associated with mortality in human heart failure (HF).
• Anthracyclines, like doxorubicin (Dox), are known cardiotoxic agents.

Purpose of the Study:

• To investigate the role of ApoM in anthracycline-induced cardiotoxicity.
• To determine the association between ApoM levels and mortality in patients with anthracycline-induced HF.
• To elucidate the protective mechanisms of ApoM against Dox-induced myocardial injury.

Main Methods:

• Animal models (mice) and human patient data were utilized.
• Circulating ApoM levels were measured in response to Dox treatment.
• Myocardial autophagic flux, cardiotoxicity, and lysosomal injury were assessed under Dox stress with varying ApoM levels.

Main Results:

• Anthracyclines (Dox) significantly reduce circulating ApoM in mice and humans.
• ApoM levels are inversely associated with mortality in patients with anthracycline-induced HF.
• ApoM heterozygosity in mice exacerbates Dox-induced mortality.
• ApoM sustains myocardial autophagic flux post-transcriptionally, attenuates Dox cardiotoxicity, and prevents lysosomal injury.

Conclusions:

• ApoM plays a protective role against anthracycline-induced cardiotoxicity.
• Maintaining ApoM levels may be a therapeutic strategy to mitigate Dox-induced heart damage.
• ApoM's mechanism involves preserving autophagic flux and preventing lysosomal injury.