TY - JOUR
T1 - Ascorbate stimulates monooxygenase-dependent steroidogenesis in adrenal zona glomerulosa
AU - Mitani, Fumiko
AU - Ogishima, Tadashi
AU - Mukai, Kuniaki
AU - Suematsu, Makoto
N1 - Funding Information:
The authors greatly acknowledge the valuable advice from Dr. H. Suzuki, Department of Pathology, School of Medicine, Keio University. We also thank Ms. R. Hoshino for excellent technical assistance. This work was supported in part by grants from Keio University and by Grants-in-aid for General Science Research and in part by Heading Project for Biosimulation from the Ministry of Education, Science, and Culture of Japan.
PY - 2005/12/9
Y1 - 2005/12/9
N2 - It is well known that ascorbic acid (Asc) is highly concentrated in the adrenal gland, but its function in the gland is not thoroughly elucidated. We therefore examined the possibility that Asc participates in steroidogenic monooxygenase systems of the adrenal cortex with the aid of the regenerating system including outer mitochondrial membrane cytochrome b (OMb). When Asc availability was limited in rat mutants unable to synthesize Asc, the increase in plasma aldosterone concentration under Na-deficiency was suppressed without effect on plasma corticosterone concentration. Aldosterone formation in the isolated mitochondrial fraction of the zona glomerulosa (zG) of the adrenal cortex was stimulated by the addition of Asc and NADH, while corticosterone formation was not. Consistently zG showed a high level of Asc regeneration activity and was rich in OMb among adrenocortical zones. Taken together, the enhanced aldosterone formation that is catalyzed by one of the steroidogenic monooxygenases, P450aldo, may be supported by Asc with its regenerating system.
AB - It is well known that ascorbic acid (Asc) is highly concentrated in the adrenal gland, but its function in the gland is not thoroughly elucidated. We therefore examined the possibility that Asc participates in steroidogenic monooxygenase systems of the adrenal cortex with the aid of the regenerating system including outer mitochondrial membrane cytochrome b (OMb). When Asc availability was limited in rat mutants unable to synthesize Asc, the increase in plasma aldosterone concentration under Na-deficiency was suppressed without effect on plasma corticosterone concentration. Aldosterone formation in the isolated mitochondrial fraction of the zona glomerulosa (zG) of the adrenal cortex was stimulated by the addition of Asc and NADH, while corticosterone formation was not. Consistently zG showed a high level of Asc regeneration activity and was rich in OMb among adrenocortical zones. Taken together, the enhanced aldosterone formation that is catalyzed by one of the steroidogenic monooxygenases, P450aldo, may be supported by Asc with its regenerating system.
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U2 - 10.1016/j.bbrc.2005.08.156
DO - 10.1016/j.bbrc.2005.08.156
M3 - Article
C2 - 16168385
AN - SCOPUS:27544442734
SN - 0006-291X
VL - 338
SP - 483
EP - 490
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 1
ER -