Amelioration by glucose-6-phosphate and NADP of potato glycoalkaloid inhibition in cell, enzyme and liposome assays

Lysis of human erythrocytes by 20 mu M chaconine was reduced by 0.5 mM gluc ose-6-phosphate (G6P) and NADP. Both compounds caused similar to 50% inhibi tion of haemolysis at 1 mM. Glucose, glucose-1-phosphate, rhamnose, galacto se and galactose-6-phosphate were ineffective; NAD was effective, although not to the extent of NADP. Of the tested sugars, only G6P reduced solanine- induced haemolysis. G6P also reduced the synergistic haemolytic action of s olanine and chaconine in combination. G6P and NADP at or above 5 mM antagon ised chaconine-induced betanin loss from excised red beet root discs; NADP was more effective than G6P. Disruption of PC/cholesterol liposomes by chac onine and inhibition of acetylcholinesterase by chaconine or solanine, were unaffected by up to 10 mM NADP or 50 mM G6P. (C) 1999 Elsevier Science Ltd . All rights reserved.