Functional, morphologic, and molecular characterization of cold storage injury

Area of Science:

• Vascular Biology
• Organ Preservation
• Molecular Medicine

Background:

• Cold storage is crucial for transplant tissue preservation, but prolonged storage leads to vascular dysfunction.
• Understanding the molecular mechanisms behind cold storage-induced vascular injury is essential for improving transplantation outcomes.

Purpose of the Study:

• To characterize the functional and molecular effects of cold storage on blood vessels.
• To identify specific molecular pathways and genes affected by cold storage.

Main Methods:

• Isometric force measurements in mouse aorta using a Mulvany myograph to assess vessel function.
• Histologic analysis of aortic cross-sections to evaluate morphologic changes.
• Microarray and polymerase chain reaction analyses to determine RNA expression alterations.

Main Results:

• Cold storage for 2 days significantly impaired vessel function, affecting potassium-induced tone and acetylcholine-induced relaxation.
• Calcium-activated potassium channels appeared impaired after 2 days of cold storage, with no significant histologic changes observed.
• RNA expression of 24 genes, including those involved in vascular tone, cardiovascular function, and calcium signaling, was altered after just 2 hours of cold storage.

Conclusions:

• Long-term cold storage negatively impacts vascular function, particularly potassium signaling via calcium-dependent potassium channels.
• Molecular analysis revealed cold storage impairs calcium signaling and vascular function pathways.
• Significant gene expression changes occur within 2 hours of cold storage, preceding observable functional impairment.