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Evidence for a Thymus-Pineal Axis
Published in Nate F. Cardarelli, The Thymus in Health and Senescence, 2019
The gonadotropic activity of JH affects the oocytes. These have three major growth phases: previtellogenesis, vitellogenesis, and chorionation. Vitellogenesis is inhibited by a low molecular weight polypeptide antigonadotropic hormone AG.219–221 JH directs transcription for vitellogenin, the predominant yolk protein precursor made in the fat body.220
Intrinsic and Extrinsic Factors That Influence Epigenetics
Published in Cristina Camprubí, Joan Blanco, Epigenetics and Assisted Reproduction, 2018
Ivan Nalvarte, Joëlle Rüegg, Carlos Guerrero-Bosagna
The terms “Environmental Epigenetics” and “Environmental Epigenomics” were first mentioned in the 2007 review article “Environmental Epigenomics and Disease Susceptibility” by Jirtle and Skinner (49). At the time, this review summarized many of the important studies that led to the conceptual definition of the terms. The trend of correlating environmental exposures and epigenetic changes, however, started much earlier, and it could be consider that the seminal paper was the 1998 review “Epigenetics and Epimutagens: Some New Perspectives on Cancer, Germline Effects and Endocrine Disrupters” by MacPhee (50). In this paper, MacPhee argues that previously published estrogen-dependent effects on the expression and DNA methylation of the vitellogenin promoter in laying hens (51) could be mimicked by the action of endocrine disruptors (EDCs), that is, compounds that alter the function of the endocrine system in organisms. In a visionary fashion, MacPhee stated: “Other epigenetic changes (inappropriate methylation, generalised hypomethylation) associated with exposure to environmental agents may also be recognised more readily in the future.” Three years later, John McLachlan also suggested that estrogens or endocrine disrupting chemicals could play a role in the programming or imprinting of genes through persistent changes in DNA methylation (52).
Hormonal Regulation of Gene Transcription
Published in Gerald M. Kolodny, Eukaryotic Gene Regulation, 2018
More recently, many examples of hormonal effects on specific mRNA levels have been documented, but the results in chick oviduct typify the essential features of the response. A good correlation between specific protein and corresponding mRNA levels or activites has been shown for vitellogenin induction by Ε in Xenopus liver,201 tryptophan oxygenase and tyrosine aminotransferase induction by C in rat liver,202,203 casein induction during pregnancy in the rabbit or rat mammary gland,204,205 α2a-globulin induction by thyroid hormones or DHT in rat liver,206,207 and growth hormone induction by thyroid hormone or Dex in cultured pituitary cells.208
Detection of anti-androgenic activity of chemicals in fish studies: a data review
Published in Critical Reviews in Toxicology, 2023
Grace H. Panter, Rebecca J. Brown, Alan Jones, Oliver Körner, Laurent Lagadic, Lennart Weltje
Several diagnostic endpoints in fish test guidelines and guidance documents could be considered sensitive to anti-androgenic substances. Such substances may act directly through binding to the androgen receptor (AR) and subsequently blocking its activation, resulting in a decrease in gene transcription, or by altering the biosynthesis, biotransformation and/or excretion of endogenous androgen hormones. Exposure to anti-androgenic substances is expected to result in androgen-dependent changes in male fish. These alterations include inhibition of spiggin, a glycoprotein synthesised by male Gasterosteus aculeatus (three-spined stickleback) to glue their nests together (Katsiadaki et al. 2002), and the reduction of quantifiable external secondary sexual characteristics (SSC), such as nuptial tubercles in Pimephales promelas (fathead minnow) and papillary processes in Oryzias latipes (Japanese medaka) (Martinović et al. 2008; Flynn et al. 2017; Wheeler et al. 2020). Effects on sexual differentiation and development would also be expected in fish exposed to anti-androgens, such as an increase in the incidence of intersex, a bias in the sex ratio towards females, a delay in testicular development, or impairment of ovarian development (Ankley and Jensen 2014; ECHA-EFSA 2018). Exposure to anti-androgens could also result in a mild induction of vitellogenin (VTG) synthesis, a phospholipoprotein under estrogenic control, in male and female fish (Ankley and Jensen 2014).
The effect of natural biomolecules on yttrium oxide nanoparticles from a Daphnia magna survival rate perspective
Published in Nanotoxicology, 2023
Egle Kelpsiene, Tingru Chang, Alexander Khort, Katja Bernfur, Inger Odnevall, Tommy Cedervall, Jing Hua
Vitellogenin-1 has previously been identified as one of the general proteins that bind to NPs after incubation with D. magna. Examples of such NPs include Au NPs (Mattsson et al. 2018), differently surface-charged polystyrene NPs (Kelpsiene et al. 2022), and Ag NPs (Gao et al. 2017). Vitellogenin-1 plays an important role in oogenesis and is highly expressed in females (Hara, Hiramatsu, and Fujita 2016, Gao et al. 2017). Hemoglobin is a polyfunctional molecule that is mainly involved in oxygen binding and transport (Ahmed, Ghatge, and Safo 2020). Serine protease has also been identified to extensively interact with 53 nm sized PS-NH2 NPs and to some extent with 200 nm sized PS-NH2 NPs (Kelpsiene et al. 2022). Our previous findings show that actin, alpha skeletal muscle commonly binds to both negatively and positively charged polystyrene NPs after incubation with D. magna (Kelpsiene et al. 2022). Actin protein plays an important role in the structure and motio of cells. Changes of its expression can lead to toxicity (Gunning et al. 2015). The presence of heat shock 70 kDa protein cognate is in line with previous findings where the protein was reported to be secreted by D. magna in response to metallic NPs (Ellis and Lynch 2020) and to 53 nm sized PS-NH2 NPs (Kelpsiene et al. 2022). Results of this study show lamin-A to only be detected in the 20–40 nm sized Y2O3 NPs sample, the same protein also shown to interact only with the 200 nm sized PS-NH2 NPs (Kelpsiene et al. 2022).
Characterization of tick salivary gland and saliva alphagalactome reveals candidate alpha-gal syndrome disease biomarkers
Published in Expert Review of Proteomics, 2021
Margarita Villar, Iván Pacheco, Lourdes Mateos-Hernández, Alejandro Cabezas-Cruz, Ala E. Tabor, Manuel Rodríguez-Valle, Albert Mulenga, Katherine M. Kocan, Edmour F. Blouin, José de La Fuente
Vitellogenin-1 and other members of the vitellogenin protein family are lipid transporters and precursors of yolk proteins and derivatives mainly synthesized in the liver as a result of coordinated endocrine stimulation that involves brain, ovary, and liver in oviparous and ovoviviparous vertebrates [83]. In Chelicerata, the main function of vitellogenins is in heme-binding hemolymph storage throughout reproduction, blood feeding and development [84]. Human ATP binding cassette (ABC) transporter proteins facilitate the ATP-dependent translocation of lipids or lipid-related compounds such as cholesterol, plant sterols, bile acids, phospholipids and sphingolipids with a positive role in lipid metabolism disorders associated for example with chronic obstructive pulmonary disease, atherosclerosis and severe alcoholic hepatitis [85,86]. However, some ABCA1 variants reduce plasma high-density lipoprotein and correlate with an increased risk of Alzheimer’s disease and related dementia and cerebrovascular disease [87]. Recently, Apostolovic et al. [33] using an allergenomics-proteomics approach identified vitellogenins in I. ricinus adults and larvae potentially associated with red meat allergy in the AGS.