Activities of glycogen phosphorylase, alanine aminotransferase and aspartate aminotransferase in adult worms ofLitomosoides cariniirecovered from pyridoxine deficient cotton rats (Sigmodon hispidus)

Abstract

SummaryThis paper demonstrates that the activities of glycogen phosphorylase (GP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) are reduced in adult worms of the filarial nematodeLitomosoides cariniirecovered from pyri-doxine-deficient cotton rats when compared to worms recovered from pyridoxine-sufficient controls. GP, ALT and AST activities were determined in adult wormsL. cariniirecovered from cotton rat hosts over a 20-week experimental period. Activities of GP, ALT and AST in the parasite showed a direct correlation with the dietary pyridoxine intake of their host. Throughout the experiment, enzyme activities were significantly lower (P< 0·001) in worms from rats fed a pyridoxine-free dietad libitumthat in worms from rats fed either a stock colony diet, a pyridoxine-free dietad libitumwith daily supplementation of 100 μg pyridoxine or limited amounts of pyridoxine-free diet with daily supplementation of 100 μg pyridoxine. The lower than normal activity of GP, ALT, AST and other enzymes dependent on the biologically active derivative of pyridoxine, the coenzyme pyridoxal-5-phosphate (PLP), interferes with the protein, carbohydrate and lipid metabolism ofL. cariniiand may in part cause the reduced establishment, development and growth of the parasite in pyridoxine-deficient hosts.