A novel 11 beta-hydroxysteroid dehydrogenase inhibitor contained in saiboku-to, a herbal remedy for steroid-dependent bronchial asthma.

Abstract

To identify the inhibitor of prednisolone metabolism contained in Saiboku-To, we conducted in-vitro experiments of 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD), using rat liver homogenate and cortisol as a typical substrate. We studied the effects of ten herbal constituents on 11 beta-HSD. Five herbal extracts showed inhibitory activity with Glycyrrhiza glabra > Perillae frutescens > Zizyphus vulgaris > Magnolia officinalis > Scutellaria baicalensis. This suggests that unknown 11 beta-HSD inhibitors are contained in four herbs other than G. glabra which contains a known inhibitor, glycyrrhizin (and glycyrrhetinic acid). Seven chemical constituents which have been identified as the major urinary products of Saiboku-To in healthy and asthmatic subjects were studied; magnolol derived from M. officinalis showed the most potent inhibition of the enzyme (IC50, 1.8 x 10(-4) M). Although this activity was less than that of glycyrrhizin, the inhibition mechanism (non-competitive) was different from a known competitive mechanism. These results suggest that magnolol might contribute to the inhibitory effects of Saiboku-To on prednisolone metabolism through inhibition of 11 beta-HSD.

• Authors: M Homma, K Oka, T Niitsuma, H Itoh
• Journal: The Journal of pharmacy and pharmacology (J Pharm Pharmacol) Vol. 46 Issue 4 Pg. 305-9 (Apr 1994) ISSN: 0022-3573 [Print] England
• PMID: 8051615 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents, Phytogenic
• Biphenyl Compounds
• Drugs, Chinese Herbal
• Glucocorticoids
• Immunosuppressive Agents
• Lignans
• saiboku-to
• magnolol
• honokiol
• Glycyrrhizic Acid
• Hydroxysteroid Dehydrogenases
• 11-beta-Hydroxysteroid Dehydrogenases
• Glycyrrhetinic Acid
• Cortisone
• Hydrocortisone

Topics

• 11-beta-Hydroxysteroid Dehydrogenases
• Animals
• Antineoplastic Agents, Phytogenic (isolation & purification, pharmacology, therapeutic use)
• Asthma (drug therapy)
• Biphenyl Compounds (isolation & purification, pharmacology, therapeutic use)
• Chromatography, High Pressure Liquid
• Cortisone (biosynthesis)
• Dose-Response Relationship, Drug
• Drugs, Chinese Herbal (chemistry, pharmacology, therapeutic use)
• Glucocorticoids (analysis)
• Glycyrrhetinic Acid (analogs & derivatives, pharmacology)
• Glycyrrhizic Acid
• Hydrocortisone (metabolism)
• Hydroxysteroid Dehydrogenases (antagonists & inhibitors)
• Immunosuppressive Agents (chemistry, pharmacology, therapeutic use)
• Lignans
• Liver (drug effects, enzymology)
• Male
• Medicine, Kampo
• Rats
• Rats, Wistar