Haemodialysis activates phospholipase A2 enzyme

Area of Science:

• Nephrology
• Biochemistry
• Inflammation Research

Background:

• Haemodialysis (HD) is recognized as an inflammatory process.
• Phospholipase A2 (PLA2) enzyme activity is crucial for producing proinflammatory lipid mediators.
• Arachidonic acid release by PLA2 is a prerequisite for many inflammatory reactions.

Purpose of the Study:

• To determine if phospholipase A2 (PLA2) activity increases during haemodialysis (HD).
• To investigate whether the increase in PLA2 activity during HD is dependent on the type of dialyser membrane used.

Main Methods:

• Eight chronic HD patients underwent dialysis using cuprophane and cellulose triacetate dialysers on separate occasions.
• Blood samples were collected from arterial and venous lines before and at 15, 60, 120, and 180 minutes after dialysis initiation.
• PLA2 activity was measured in both crude plasma and plasma extract.

Main Results:

• Baseline PLA2 activity was significantly higher in HD patients than in normal subjects.
• PLA2 activity in crude plasma increased during HD, peaking at 15 minutes, with a more pronounced rise using cuprophane membranes.
• PLA2 activity in plasma extract increased only when using cuprophane membranes, not cellulose triacetate.

Conclusions:

• Plasma PLA2 activity is elevated in HD patients and further increases during the dialysis procedure.
• The extent of PLA2 activation during HD is greater with less biocompatible membranes like cuprophane.
• Continuous PLA2 activation during HD may contribute to long-term adverse effects.