Disease relevance of Ecdysterone

• Alterations in the pattern of DNase I hypersensitivity were observed on ecdysterone-stimulated transcription of Drosophila melanogaster small heat shock protein genes [1].
• Two recombinant phages were selected for hybridizing very intensively with poly(A)+ RNA of ecdysterone-treated cells and very weakly with poly(A)+ RNA of untreated ones [2].
• 20-Hydroxyecdysone levels, but not juvenile hormone degradation, change following heat stress in mutant females [3].
• In experiments using this system to culture O. volvulus mf (ex utero) derived from adult female worms but with the addition of reduced glutathione and/or 20-hydroxyecdysone, parasites were consistently more active over a 70-day period than those cultured without these additives [4].
• Muscle atrophy is induced by a dramatic decline in the endogenous titres of the steroid moulting hormone 20-hydroxyecdysone [5].

Psychiatry related information on Ecdysterone

• These results show that the presence of ecdysterone source is necessary for the induction of the late puffs up to a critical period at L4 stage [6].
• Incubations of the CNS with 1 microgram ml-1 20-hydroxyecdysone (20-HE) resulted in the onset of the same pattern of sustained motor activity [7].
• Effect of 20-hydroxyecdysone on cannibalism, sexual behavior, and contact sex pheromone in the solitary female spider, Tegenaria atrica [8].

High impact information on Ecdysterone

• The control of ecdysterone-regulated puffs in Drosophila salivary glands [9].
• The hormone ecdysterone induces a characteristic sequence of changes in puffing activity in the salivary gland chromosomes of Drosophila melanogaster [9].
• The addition of physiological concentrations of the arthropod molting hormone 20-hydroxyecdysone results in the cessation of cell division in the Kc cell line of Drosophila melanogaster [10].
• In ecdysone-sensitive Drosophila Kc cells, the insecticide RH 5849 (1,2-dibenzoyl-1-tert-butylhydrazine) mimics the action of 20-hydroxyecdysone by causing the formation of processes, an inhibition of cell proliferation, and induction of acetylcholinesterase [11].
• After ingestion of blood, 20-hydroxyecdysone activates yolk protein precursor (YPP) genes in the metabolic tissue, the fat body [12].

Chemical compound and disease context of Ecdysterone

• Simultaneously, a significant toxicity of troglitazone to HepG2 cells was observed. betaTC3 cells were not stimulated by ecdysterone, that is, no secretogogue effect of ecdysterone was observed [13].
• While 20-hydroxyecdysone and DES were highly toxic, the other compounds tested show no significant toxicity to copepods [14].

Biological context of Ecdysterone

• A sequence element, which also occurs in the promoters of several other developmentally regulated Drosophila genes, is present in regions of the hsp23 promoter that are essential for its ecdysterone, but not its heat-regulated activity; this element may represent a binding site for an ecdysterone--receptor complex [15].
• The 2B5 region of the X-chromosome in Drosophila melanogaster plays a developmentally important role in the ecdysterone-triggered response of the late third instar salivary gland [16].
• Selective gene expression induced by ecdysterone in cultured fat bodies of Drosophila [17].
• Shade is the Drosophila P450 enzyme that mediates the hydroxylation of ecdysone to the steroid insect molting hormone 20-hydroxyecdysone [18].
• Mosquito vitellogenesis is regulated by the steroid hormone 20 hydroxyecdysone (20E) [19].

Anatomical context of Ecdysterone

• Such disks can be made to grow at a normal rate by supplementing the culture medium with an optimal concentration of the steroid hormone 20-hydroxyecdysone and with hemolymph taken from growing larvae [20].
• The effect of various types of DNA sequence alterations on the activity of the ovarian, ecdysterone, and heat-shock-responsive promoters of the Drosophila melanogaster hsp27 gene was studied by P element-mediated germ line transformation [21].
• During the metamorphic reorganization of the insect central nervous system, the steroid hormone 20-hydroxyecdysone induces a wide spectrum of cellular responses including neuronal proliferation, maturation, cell death and the remodeling of larval neurons into their adult forms [22].
• Expansion of the central arborizations of persistent sensory neurons during insect metamorphosis: the role of the steroid hormone, 20-hydroxyecdysone [23].
• The orphan nuclear receptors BmE75 and BmHR3 are induced by 20-hydroxyecdysone in the ovary of the silk moth Bombyx mori at the beginning of pupation and show stage-specific expression in ovarian follicles during pharate adult development [24].

Associations of Ecdysterone with other chemical compounds

• The temporal and spatial expression of this RNA is correlated with the expression of the GLD enzyme and levels of the steroid hormone ecdysterone [25].
• When the pattern of gene expression is altered after injection of either 20-hydroxyecdysone or actinomycin D, the muscles persist. cDNA clones have been isolated for four genes that become abundantly expressed coincident with the commitment to degenerate [26].
• Previous studies have suggested that production of 20-hydroxyecdysone in Drosophila and other arthropods involves a series of cytochrome P450 catalyzed hydroxylations of cholesterol [27].
• Furthermore, the phenotype is rescued by application of 20-hydroxyecdysone or the precursor 7-dehydrocholesterol [28].
• An apical surface glycoprotein, designated gp125 for its apparent molecular weight of 125,000, appears in Ca2(+)-free, ionic detergent extracts of imaginal discs of Drosophila melanogaster in response to the steroid hormone, 20-hydroxyecdysone (20-HE) [29].

Gene context of Ecdysterone

• 20-Hydroxyecdysone stimulates the accumulation of translatable yolk polypeptide gene transcript in adult male Drosophila melanogaster [30].
• Hybridization of a nick-translated genomic clone containing the hsp23 gene to a total RNA blot showed that ecdysterone stimulation of hsp23 synthesis was the result of an increase in the hsp23 RNA content of S3 cells [31].
• 20-hydroxyecdysone can override the sex-determination system and induce yolk protein synthesis in normal males and tra-2ts reared and maintained at the restrictive temperature [32].
• Physiological levels of 20-hydroxyecdysone induced the synthesis of ACE-like activity and Ance protein by a wing disc cell line (Cl.8+), confirming that Ance is an ecdysteroid-responsive gene [33].
• Like, USP, it activates transcription in Drosophila Schneider S2 cells in a 20-hydroxyecdysone-dependent manner, via its interaction with the endogenous EcR protein [34].

Analytical, diagnostic and therapeutic context of Ecdysterone

• The level of Croquemort, a candidate phagocytosis receptor of Drosophila hemocytes/macrophages, increased in l(2)mbn cells after treatment with 20-hydroxyecdysone, whereas that of Draper, another candidate phagocytosis receptor, remained unchanged [35].
• Developmental expression by Northern blot analysis reveals that, during the 5th larval instar, MsE74B expression correlates with pupal commitment on day 3 and is induced to maximal levels within 12h by low levels of 20-hydroxyecdysone (20E) and repressed by physiologically relevant levels of juvenile hormone I (JH I) [36].
• Cell culture experiments show that the PCD of APRs in abdominal segment 6 [APR(6)s] is a cell-autonomous response to the steroid hormone 20-hydroxyecdysone (20E) and involves mitochondrial demise and cell shrinkage [37].
• Ligation followed by 20HE infusion showed that the disappearance of FSP from the hemolymph during the prepupal period was controlled by the rising ecdysteroid titer [38].
• By the use of in vitro culture techniques, it has been demonstrated that the first bout of mitosis in both glands proceeds in basal medium, while the second bout of mitosis requires a physiological level of ecdysterone [39].

References