Lysosomal enzyme release in hypothermically perfused dog kidneys

Area of Science:

• Organ preservation
• Cellular biology
• Biochemistry

Background:

• Hypothermic perfusion preservation is crucial for organ transplantation.
• Lysosomal integrity is vital for cellular function and organ viability.
• Understanding lysosomal disruption during preservation is key to improving outcomes.

Purpose of the Study:

• To investigate lysosomal disruption in kidneys during hypothermic perfusion preservation.
• To explore the relationship between lysosomal damage and organ viability.
• To evaluate methylprednisolone as a potential lysosomal stabilizer.

Main Methods:

• Analysis of free and bound enzyme activity for beta-glucuronidase, cathepsin-D, and aryl sulfatase in canine kidney cortex.
• Comparison of enzyme activity after varying periods of hypothermic perfusion (up to 5 days) with warm ischemia controls.
• Assessment of methylprednisolone pretreatment effects on lysosomal enzyme activity.

Main Results:

• All three lysosomal enzymes showed increased free activity (47-68%) during 5 days of perfusion.
• Severe kidney damage was indicated by enzyme activity levels similar to 4-hour warm ischemia.
• Aryl sulfatase was the most sensitive indicator of severe damage.
• Methylprednisolone pretreatment reduced free lysosomal enzyme activity in 5-day preserved kidneys.

Conclusions:

• Extensive lysosomal disruption occurs during hypothermic perfusion preservation.
• This disruption may be a significant factor in the loss of organ viability.
• Methylprednisolone shows potential in mitigating lysosomal damage during long-term kidney preservation.