Ecdysteroids

Abstract

Ecdysteroid: member of a class of polyhydroxylated steroids found in invertebrate animals (zooecdysteroids; moulting hormones), plants (phytoecdysteroids) and fungi (mycoecdysteroids). Over 500 structural analogues are currently known. Biosynthetically, they derive from C27-, C28- or C29-sterols. The most frequently encountered analogue (in arthropods and plants) is 20-hydroxyecdysone (2β,3β,14α, 20R,22R,25-hexahydroxycholest-7-en-6-one). In arthropods, ecdysteroids occur universally and regulate development by inducing moulting and reproduction, where their action is mediated by high-affinity binding to an intracellular member of the class of nuclear receptor (NR) proteins (ecdysteroid receptor; EcR) dimerised with a second NR (USP/RxR). This receptor complex binds to specific DNA promoter sites and regulates gene expression. In plants, ecdysteroids are a class of secondary compounds, occurring in varying amounts in certain species, but not all in others. Phytoecdysteroids are believed to contribute to the reduction of invertebrate predation by acting as feeding deterrents or endocrine disruptors. Ecdysteroids also possess a wide range of positive pharmacological effects in mammals, where the mode of action involves moderate-affinity binding to plasma-membrane-bound receptors and not interaction with the classical NRs for vertebrate steroid hormones.

The Anabolic Effect of Fenugreek: A Systematic Review with Meta-analysis

“…Nevertheless, it can currently be assumed that chronic FEN application does not influence bench press performance. Consequently, the results are in contrast to the effect on lower body performance and other phytosteroids [44,45].…”

Ecdysteroids from the Korean Endemic Species Ajuga spectabilis with Activities against Glucocorticoid Receptors and 11β-Hydroxysteroid Dehydrogenase Type 1

“…In all naturally arising ecdysteroids, the A/B ring junction is generally cis and hardly ever trans , whereas the B/C and C/D ring junctions are always trans. In the NOESY spectrum of 1 (Figure ), the strong correlations between H-2/H-9 supported a cis A/B ring junction. The α-configurations of H-2 and H-3 could be confirmed by the large and small coupling constants ( 3 J H‑1β/H‑2 = 12.1 Hz and 3 J H‑2/H‑3 = 3.1 Hz), respectively.…”

Phytochemical Screening and Pesticidal Efficacy of Phytoecdysteroid Fraction of a Fern Pityrogramma Calomelanos (L.) Link Against Spodoptera Litura (Fabricius.)

“…Similarly, Xavier et al (2016) reported the phytoecdysteroid fraction of C. dentata and N. cordifolia with the occurrence of tannins, steroids, phenolic compounds and terpenoids. Among the pteridophytes, Cheilanthes tenufolia, Polypodium vulgare (Lafont et al, 2021), Pteridium aquilinum, Seratula tinctora, Cheilanthes farinosa (Rajkumar et al, 2000), Christella parasitica, Pteridium aquilinum and Hemionitis arifolia (Sahayaraj and Selvaraj, 2013) were reported to contain phytoecdysones. UV-Visible spectrophotometry analysis of phytochemicals in the phytoecdysteroid fraction P. calomelanos showed six prominent peaks at the wavelength ranging between 326.5nm -666nm.…”

“…Various authors reported the absorption spectrum of different phytochemicals that include steroids (200-400nm) and polyphenols (240-650nm) (Zahari et al, 2016). UV absorbance of 20 -E (ecdysteroid analogue) recorded at 242nm and 310nm (Lafont et al, 2021). Raimana et al (2008) reported a typical ecdysteroid spectrum with a maximum wavelength of 242nm and two unusual peaks at 294 and 317nm indicated the presence of an aromatic conjugating moiety.…”