New 8-prenylated quercetin glycosides from the flowers of Epimedium acuminatum and their testosterone production-promoting activities

Abstract

Phytochemical investigation was carried out for the flowers of Epimedium acuminatum Franchet. by first conducting LC-MS analysis, leading to the identification of 32 compounds. Furthermore, guided by LC-MS profiling, three new 8-prenylated quercetin glycosides (3′-hydroxylikarisoside C, 3′-hydroxylepimedoside E, 3′-hydroxyldiphylloside B), one new anthocyanin (delphinidin-3-O-p-coumaroyl-sophoroside) and six known compounds were isolated from the flowers of E. acuminatum for the first time, and their structures were characterized based on spectroscopic methods including 1D and 2D NMR, and HRESIMS. Combining our discoveries and literature survey, a revised classification of Epimedium flavonols was proposed as Type A (8-prenylated kaempferol based), which was further subdivided into subtype icaritin and subtype demethylicaritin, and Type B (8-prenylated quercetin based), which was further subdivided into subtype 3′-hydroxylicaritin and subtype 3′-hydroxyldemethylicaritin. The structure-activity relationship (SAR) study was carried out by comparing testosterone production-promoting activities of all the new compounds along with nine related Epimedium flavonols, revealing that the new 8-prenylated quercetin glycosides (subtype 3′-hydroxyldemethylicaritin in Type B) exhibited lower testosterone production-promoting activities in rat primary Leydig cells than Epimedium flavonols of subtype demethylicaritin in Type A, but possessed higher activities than the Epimedium flavonols of subtype icaritin in Type A. These results suggested that either methylation at C-4′ position or hydroxylation at C-3′ position of ring B could significantly reduce the testosterone production-promoting activities of Epimedium flavonols.

Effect of quercetin administration on electron microscopic changes in testicular interstitial endocrinocytes during long-term central blockade of luteinising hormone in rats

“…They are likely to maintain the constancy of cell composition in this population. Literature data [9,29,36] and our results confirm that no mitotic activity is detected in the pubertal population of endocrinocytes [10,35]. Changes in mitochondrial structure and a decrease in cell cytoplasm volume, observed in the early stages of the tryptorelin experiment, suggest that steroid hormone synthesis, initiated at the endoplasmic reticulum, is completed in these organelles.…”

Prenylated Flavonoids of Genus Epimedium: Phytochemistry, Estimation and Synthesis

“…[27] Three new prenylated flavonoids: 3'-hydroxyl ikarisoside C (77), 3'-hydroxyl epimedoside E (19 c) and 3'-hydroxyl diphyloside B (19 d) have been isolted from E. accuminatum. [33] Similarly different known and new molecules have been isolated from different species of Epimedium in last ten years (Table 1).…”

The Influence of Quercetin on the Production of Reactive Oxygen-Nitrogen Forms in the Structure of the Interstitial Space of Rat Testicles With Long-Term Effect of Triptorelin

“…Кверцетин -це поширений флавоноїд, природний пігмент, який присутній у складі багатьох фруктів, овочів та насіння [23]. Флавоноїди допомагають уникнути розвитку хвороб серцевосудинної системи, знижують ризик виникнення дегенеративних процесів у головному мозку онкологічних захворювань [16].…”