Decreased phospholipase A2 activity in butyrate differentiated HT29 cells.

Our earlier work has shown that in butyrate differentiated colonic HT29 cells, there is an alteration in phospholipid composition as compared to control. To know more about these changes, butyrate treated and control cell homogenates were incubated in presence of calcium and phospholipids were analyzed. It was observed that incubation with calcium was associated with increase in lysophosphatidylcholine (lysoPC) and free fatty acids and the increase was much higher in control as compared to butyrate treated cells. There was no alteration in lysoPC content. These products are formed by the action of phospholipase A2 (PLA2) which is activated by calcium and suggests that butyrate-induced differentiation is associated with decrease in PLA2 activity.