TY - JOUR
T1 - Differential effects of glucose and fructose on hexose metabolism in dog spermatozoa
AU - Rodriguez Gil, Juan Enrique
AU - Otaegui Goya, Pedro Jose
AU - Mogas Amoros, Maria Teresa
AU - Palomo Peiro, Maria Jesus
AU - Rigau Mas, Teresa Josefa
AU - Rivera, M.
AU - Fernández-Novell, J. M.
AU - Ballester, J.
AU - Peña, A.
AU - Guinovart, J. J.
PY - 2002/1/1
Y1 - 2002/1/1
N2 - Incubation of dog spermatozoa with 10 mmol I-1 glucose or fructose rapidly increased the intracellular content of glucose 6-phosphate and fructose 6-phosphate, although the effect of fructose was greater. These effects were correlated with increases in ATP, ribose 5-phosphate and glycogen contents, and in the rates of formation of L-lactate and CO2. In all cases, except for ATP and glycogen, the effect of fructose was greater than that of glucose. The total hexokinase activity of the crude extracts of dog spermatozoa was more sensitive to fructose than to glucose at lower concentrations (0.1-3.0 mmol l-1). Both monosaccharides induced a fast and intense increase in the overall tyrosine phosphorylation of dog spermatozoa, although their specific induced-phosphorylation patterns differed slightly. Glut 3 and Glut 5 hexose transporters were the main hexose transporters in dog spermatozoa; however, other possible SGLT family-related hexose transporters were also localized. These data indicate that, at concentrations from 1 mmol I-1 to 10 mmol l-1, fructose has a stronger effect than glucose on hexose metabolism of dog spermatozoa. These differences appear to be related to variations in the sensitivity of hexokinase activity. Moreover, the differential hexose metabolism induced by the two sugars had distinct effects on the function of dog spermatozoa, as revealed by the diverse patterns of tyrosine phosphorylation.
AB - Incubation of dog spermatozoa with 10 mmol I-1 glucose or fructose rapidly increased the intracellular content of glucose 6-phosphate and fructose 6-phosphate, although the effect of fructose was greater. These effects were correlated with increases in ATP, ribose 5-phosphate and glycogen contents, and in the rates of formation of L-lactate and CO2. In all cases, except for ATP and glycogen, the effect of fructose was greater than that of glucose. The total hexokinase activity of the crude extracts of dog spermatozoa was more sensitive to fructose than to glucose at lower concentrations (0.1-3.0 mmol l-1). Both monosaccharides induced a fast and intense increase in the overall tyrosine phosphorylation of dog spermatozoa, although their specific induced-phosphorylation patterns differed slightly. Glut 3 and Glut 5 hexose transporters were the main hexose transporters in dog spermatozoa; however, other possible SGLT family-related hexose transporters were also localized. These data indicate that, at concentrations from 1 mmol I-1 to 10 mmol l-1, fructose has a stronger effect than glucose on hexose metabolism of dog spermatozoa. These differences appear to be related to variations in the sensitivity of hexokinase activity. Moreover, the differential hexose metabolism induced by the two sugars had distinct effects on the function of dog spermatozoa, as revealed by the diverse patterns of tyrosine phosphorylation.
U2 - 10.1530/rep.0.1230579
DO - 10.1530/rep.0.1230579
M3 - Article
SN - 1470-1626
VL - 123
SP - 579
EP - 591
JO - Reproduction
JF - Reproduction
IS - 4
ER -