TY - JOUR
T1 - Inactivation by chloroquine of α-galactosidase in cultured human skin fibroblasts
AU - De Groot, Philip G.
AU - Elferink, Ronald Oude
AU - Hollemans, Marja
AU - Strijland, Anneke
AU - Westerveld, Andries
AU - Khan, P. Meera
AU - Tager, Joseph M.
PY - 1981/12
Y1 - 1981/12
N2 - When human skin fibroblasts are cultured in the presence of chloroquine or NH4Cl there is a decrease in the intracellular level of lysosomal hydrolases and a concomitant increase in the extracellular activity as compared with cells grown in the absence of a base (cf [18]). In a medium with 25 μM chloroquine or 5 mM NH4Cl, the decrease in the intracellular activity of β-hexosaminidase, arylsulphatase and β-glucuronidase is 10-40% after 1 day. A similar decrease in α-galactosidase activity is observed in cells grown in the presence of 5 mM NH4Cl. However, in the presence of 25 μM chloroquine, the intracellular activity of α-galactosidase decreases by 80-90% within 6 h. The inactivation is irreversible. After removal of the chloroquine and further culture of the cells in chloroquine-free medium, α-galactosidase activity gradually increases due to de novo synthesis. The turnover time of α-galactosidase was calculated to be 1.9 days. Inactivation of α-galactosidase also occurs when homogenates are incubated with chloroquine, but the concentration of the base required for maximum inactivation is at least three orders of magnitude higher than that which must be present in the medium of intact cells to obtain the same effect.
AB - When human skin fibroblasts are cultured in the presence of chloroquine or NH4Cl there is a decrease in the intracellular level of lysosomal hydrolases and a concomitant increase in the extracellular activity as compared with cells grown in the absence of a base (cf [18]). In a medium with 25 μM chloroquine or 5 mM NH4Cl, the decrease in the intracellular activity of β-hexosaminidase, arylsulphatase and β-glucuronidase is 10-40% after 1 day. A similar decrease in α-galactosidase activity is observed in cells grown in the presence of 5 mM NH4Cl. However, in the presence of 25 μM chloroquine, the intracellular activity of α-galactosidase decreases by 80-90% within 6 h. The inactivation is irreversible. After removal of the chloroquine and further culture of the cells in chloroquine-free medium, α-galactosidase activity gradually increases due to de novo synthesis. The turnover time of α-galactosidase was calculated to be 1.9 days. Inactivation of α-galactosidase also occurs when homogenates are incubated with chloroquine, but the concentration of the base required for maximum inactivation is at least three orders of magnitude higher than that which must be present in the medium of intact cells to obtain the same effect.
UR - http://www.scopus.com/inward/record.url?scp=0019768235&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/0014-4827(81)90011-2
DO - https://doi.org/10.1016/0014-4827(81)90011-2
M3 - Article
C2 - 6273196
SN - 0014-4827
VL - 136
SP - 327
EP - 333
JO - Experimental cell research
JF - Experimental cell research
IS - 2
ER -