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Evidence for a Thymus-Pineal Axis
Published in Nate F. Cardarelli, The Thymus in Health and Senescence, 2019
In 1954 Butenandt and Karlson isolated and purified ecdysone, the molting hormone, from the PT.139 A year later, several other molting hormones were isolated, β-ecdysone from insects and crustecdysone from crustaceans.140 Ecdysone was found to be active when ingested.141 It is a steroid having a molecular weight of 464 Da and is synthesized from exogenous cholesterol.142 (Most insects cannot synthesize cholesterol and therefore require an external source.143,144 In a sterol-free diet, larva fail to grow.143)The structure of ecdysone (or ecdysterone) has been completely characterized.145 Ecdysone acts directly on DNA resulting in the synthesis of various peptide enzymes.146 Crustecdysone has also been structurally analyzed and found to be the same as β-ecdysone.147,148
Phytoecdysteroids
Published in Amritpal Singh Saroya, Contemporary Phytomedicines, 2017
A new ecdysone hormone, rhaponticum, and ecdysterone have been isolated (Deng et al. 2000). Ecdysterone, ajugasterone C, ajugasterone C-20,22-monoacetonide, ajugasterone C-2,3,20,22-diacetonide and 5-deoxykaladasterone-20,22- monoacetonide have been reported (Zhang and Wang 2001).
Affinity Modification in Biochemistry, Biology, and Applied Sciences
Published in Dmitri G. Knorre, Valentin V. Vlassov, Affinity Modification of Biopolymers, 1989
Dmitri G. Knorre, Valentin V. Vlassov
Another example of localization of the ligand binding sites on the target is the experiment on visualization of ecdysterone binding sites on polytene chromosomes of Drosophila melanogaster. The hormone ecdysterone stimulates specific genes on polytene chromosomes of Diptera and causes changes in the pattern of specific structural modifications, so-called puffs, present in chromsomes. In order to learn if there are specific chromosomal sites for the hormone binding, direct UV cross-linking of endogenous ecdysterone to chromosomes in salivary glands of D. melanogaster was performed. The chromosome preparations were treated with antiecdysterone rabbit antibodies and the latter were developed with fluorescein isothiocyanate-coupled goat antirabbit immunoglobulins in order to visualize the ecdysterone binding sites by the fluorescence microscopy. The microscopic investigation revealed the specific pattern of ecdysterone binding to various chromosomal loci that are known to respond to the hormone.501 It should be emphasized that analysis of the ecdysterone binding sites was only possible when the hormone could be covalently linked to the binding sites, because preparation of the chromosome samples requires denaturating treatments which remove the noncovalently bound hormone.
Comparison of pharmacokinetics of phytoecdysones and triterpenoid saponins of monomer, crude and processed Radix Achyranthis Bidentatae by UHPLC-MS/MS
Published in Xenobiotica, 2020
Liu Yang, Hai Jiang, Meiling Yan, Xudong Xing, Xinyue Guo, Wenjing Man, Ajiao Hou, Bingyou Yang, Qiuhong Wang, Haixue Kuang
Mass spectrometric detection was carried out using a Thermo TSQ QUANTIS triple quadruple mass spectrometer using an electrospray ionization (ESI) source operated in negative ion mode and the data were acquired using the Trace Finder™ (Thermo Fisher Scientific, Waltham, MA) software. The parameters in the source were set as follows: spray voltage 3000 V, Sheath Gas of 40 units; Aux Gas of 10 units; Ion Transfer Tube Temp and Vaporizer Temp were set at 325 and 350 °C. All analytes were monitored via multiple reaction monitoring to be for the analysis of β-ecdysterone (m/z 479.5 1 9 → 319.000), ginsenoside R0 (m/z 955.7 4 5 → 793.500), chikusetsusaponin IVa (m/z 793.6 7 8 → 631.400) and glycyrrhizin (I.S.) (m/z 255.2 0 7 → 119.000). There are isomers (β-ecdysterone, 25-R inokosterone and 25-S inokosterone) that have the same m/z for the precursor and product ions, which only showed the MS/MS spectra of β-ecdysterone. The collision energies (CE) were 25.43, 28.54, 47.04 and 55.00 V, respectively. The structures and representative product ion mass spectra of these compounds are presented in Figure S1.
Physical exercise, nutrition and hormones: three pillars to fight sarcopenia
Published in The Aging Male, 2019
Paolo Sgrò, Massimiliano Sansone, Andrea Sansone, Stefania Sabatini, Paolo Borrione, Francesco Romanelli, Luigi Di Luigi
A growing interest is present regarding anabolic effects of ecdysterone, a promising selective estrogen receptor beta agonist [82,83] (Figure 3). Last but not least, it seems that alkali-supplemented diets decrease urinary nitrogen excretion expressed as ratio to same day nitrogen intake, reducing muscle protein breakdown [84,85]. High-protein diet may increase the amount of acidic byproducts affecting negatively musculoskeletal system; the introduction of alkaline salts in diet may result in a more favorable environment for muscle conservation. Low-grade metabolic acidosis appears to stimulate proteolysis pathways. This stimulus can be triggered by an increased production of glucocorticosteroids, such as cortisol [86,87].
Nanoformulations and their mode of action in insects: a review of biological interactions
Published in Drug and Chemical Toxicology, 2021
Kiran Shahzad, Farkhanda Manzoor
NPs such as TiO2-NPs have demonstrated protective effects in studies with the silkworm, Bombyx mori. TiO2-NPs given orally are shown to mitigate oxidative stress and midgut damage from phoxim while increasing growth, body and cocoon weight, feeding efficiency, and upregulating trehalase, protease, and lipase activity (Wang et al.2015). TiO2-NPs were also observed to increase expression levels of some genes in the insulin signaling pathway; protein, carbohydrate, and lipid metabolism as well as the expression of Hsp70, TPx, SOD, and CAT which indicate upregulated antioxidant activity; while decreased levels of TiO2 may help alleviate oxidative damages of high temperature at 30 °C (Tian et al.2016, Li et al.2018). TiO2-NPs alter silk protein synthesis in B. mori by influencing the Akt/Tor (protein kinase B (Akt)/Target of rapamycin (Tor) signaling) pathway. Li et al. (2014) noted that treatment with TiO2-NPs resulted in the upregulation of transcription of rapamycin-related proteins and four cytochrome P450 genes (CYP306A1, CYP302A1, CYP315A1, and CYP314A1); increased expression of ecdysterone receptors P70S6K and pi3k and ultimately reduced the development and molting period. Xue et al. (2018) further noted that TiO2-NPs upregulated mRNA accumulation for Tor1, Tor2, and Akt and increased the phosphorylation of Akt as well as its downstream proteins. Eventually, all the signaling resulted in the regulation of the mRNA expression of the protein Fib-L, one of the major constituents of the silk protein. In addition, the oral dosage of AgNPs also promotes silkworm growth, and higher doses cause death (Meng et al.2017).