Hexose-6-phosphate dehydrogenase in the endoplasmic reticulum.
Hexose-6-phosphate dehydrogenase (H6PD) is a luminal enzyme of the endoplasmic reticulum that is distinguished from cytosolic glucose-6-phosphate dehydrogenase by several features. H6PD converts glucose-6-phosphate and NADP(+) to 6-phosphogluconate and NADPH, thereby catalyzing the first two reactions of the pentose-phosphate pathway. Because the endoplasmic reticulum has a separate pyridine nucleotide pool, H6PD provides NADPH for luminal reductases. One of these enzymes, 11beta-hydroxysteroid dehydrogenase type 1 responsible for prereceptorial activation of glucocorticoids, has been the focus of much attention as a probable factor in the pathomechanism of several human diseases including insulin resistance and the metabolic syndrome. This review summarizes recent advances related to the functions of H6PD.
Department of Pathophysiology, Experimental Medicine and Public Health, University of Siena, I-53100 Siena, Italy.
Silvia
S
Senesi
Miklos
M
Csala
Paola
P
Marcolongo
Rosella
R
Fulceri
Jozsef
J
Mandl
Gabor
G
Banhegyi
Angelo
A
Benedetti
D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1 / Q000235:genetics / Q000378:metabolism; D000818:Animals; D003349:Cortisone Reductase / Q000172:deficiency; D004721:Endoplasmic Reticulum / Q000201:enzymology*; D005954:Glucosephosphate Dehydrogenase / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D009249:NADP / Q000378:metabolism*; D010427:Pentose Phosphate Pathway
D009249:NADP; D043205:11-beta-Hydroxysteroid Dehydrogenase Type 1; D005954:Glucosephosphate Dehydrogenase; D003349:Cortisone Reductase