The function of dihydrodiol dehydrogenase during development

Research Project

Project/Area Number	13672291
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Biological pharmacy
Research Institution	Gifu Pharmaceutical University
Principal Investigator	DEYASHIKI Yoshihiro Gifu Pharmaceutical University, Lecturer, 薬学部, 講師 (00202193)
Project Period (FY)	2001 – 2003
Project Status	Completed (Fiscal Year 2003)
Budget Amount *help	¥3,500,000 (Direct Cost: ¥3,500,000) Fiscal Year 2003: ¥600,000 (Direct Cost: ¥600,000) Fiscal Year 2002: ¥1,000,000 (Direct Cost: ¥1,000,000) Fiscal Year 2001: ¥1,900,000 (Direct Cost: ¥1,900,000)
Keywords	dihydrodiol dehydrogenase / hydroxysteroid dehydrogenase / development / mouse / ヒドロキシステロイド脱水素酵素 / 遺伝子クローニング
Research Abstract	To clarify the expression of dihydrodiol dehydrogenase (mDD) in mouse tissues during development, an ELISA for mDD and an RT-PCR condition specific to mDD mRNA were developed. mDD antigen levels in liver, stomach and small intestine were remarkably higher than those in other tissues during development. The same tendency was observed in the case of mDD mRNA. The ratio of mDD antigen to total protein in crude extracts of liver and stomach increased with age. The enzymatic activity in mouse tissues for representative substrate of mDD (indanol) did not correspond with the antigen level, suggesting that the existence of isoenzyme(s) for the substrate and the necessity of finding more suitable substrate to determine mDD specific activity. The analysis of catalytic property of mDD showed mDD preferred NAD(H) to NADP(H) as a cofactor, reduced some physiological carbonyl compounds such as diacetyl and isatine and xenobiotic carbonyl compounds, oxidized some hydroxysteroids including 5α-pregnan-3α-ol-20-one and 5α-androstan-17β-ol-3-one and xenobiotics such as carcinogenic polycyclic aromatic hydrocarbons and was inhibited by bile acids such as lithocholic acid and some steroidal hormones. mDD cloned in the present study is found to be a new member of the aldo-keto reductase superfamily and may be involved in the detoxification of xenobiotics, in the metabolism of some endogenous carbonyl compounds and steroids and partly in the activation of carcinogenic compounds derived from polycyclic aromatic hydrocarbons in digestive system including liver, stomach and small intestine after its birth. mDD may also play an important role in the maintenance of pregnancy leading to the growth of embryo by metabolizing some steroidal hormones. The enzymatic activity of mDD is suggested to be regulated by endogenous compounds such as lithocholic acid and some steroidal hormones.