Characterization of in vitro metabolites of toad venom using high-performance liquid chromatography and liquid chromatography - Mass spectrometry

金沢大学大学院大学院自然科学研究科分子作用学金沢大学薬学部The characterization of the in vitro metabolites of toad venom, which has been widely used as a traditional Chinese drug, Ch\u27an Su, has been completed. Toad venom contains bufotoxins (such as marinobufotoxin; marinobufagin 3-suberoylarginine ester) and bufogenins (such as marinobufagin and bufalin) as the main cardiac steroids. An in vitro experiment using the rat or human liver cytosolic fraction disclosed that marinobufotoxin produced marinobufagin, but not its 3-hemisuberate. Marinobufagin was subjected to the enzyme reaction using the rat or human liver microsomal fraction together with NADPH and NAD, which produced 3-dehydromarinobufagin and 3-epimarinobufagin. Marinobufagin produced its 3-sulfate upon treatment with the rat or human liver cytosolic fraction and 3′-phosphoadenosine 5′-phosphosulfate. Bufalin was also subjected to the above enzyme reactions and showed almost the same results except for the result that the hydroxylation occurred at the 5β-position. On the other hand, small amounts of marinobufagin 3-glucuronide were obtained only by treatment with the human liver microsomal fraction and uridine 5′-diphosphoglucuronic acid. The structures of these metabolites were confirmed using authentic samples regarding their high-performance liquid chromatographic behavior and/or liquid chromatography-mass spectrometry analysis. Copyright © 2006 John Wiley & Sons, Ltd

Sex differences in the serum level of endogenous ligands for estrogen receptor beta in the elderly population

Animal studies suggest that estrogen receptor beta (ER beta)-agonists, but not ER alpha-agonists, are antidepressants. Several endogenous ligands for ER beta have been proposed, including 5 alpha-androstane-3 beta,17 beta-diol (3 beta Adiol), Androstenediol (Delta 5-diol), and 7 alpha-hydroxydehydroepiandrosterone (7 alpha-OH-DHEA). The aim of this study was to determine the serum and salivary levels of natural ER beta ligands in men and women with and without past depressive episodes in the elderly population. DHEA (a precursor of 3 beta Adiol, Delta 5-diol, and 7 alpha-OH-DHEA), 17 beta-estradiol (E2), and cortisol (F) were also measured. Samples were collected from 51 subjects and liquid chromatography tandem mass spectrometry was used for measurement. Comparisons were made between groups based on sex and depression history. E2, 3 beta Adiol, and Delta 5-diol levels were significantly lower in women than in men regardless of depression history. There were no significant differences between men and women in DHEA or 7 alpha-OH-DHEA levels. DHEA was significantly lower in women with depression than in women without depression. Reduced DHEA levels may be related to depression vulnerability in women. Further studies are needed to determine the mechanism underlying sex differences in the prevalence of depression and increased risk of depression during menopause. Not only E2 but also two other estrogenic steroids (3 beta Adiol and Delta 5-diol) should be involved in these studies.ArticleSCIENTIFIC REPORTS. 6:25878 (2016)journal articl