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Oxyfunctionalization of Pharmaceuticals by Fungal Peroxygenases
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Jan Kiebist, Martin Hofrichter, Ralf Zuhse, Katrin Scheibner
Another study dealt with the selective oxyfunctionalization of diverse steroids, including free and esterified sterols, steroid hydrocarbons and ketones, by three different UPOs (AaeUPO, MroUPO and rCciUPO). As for vitamin D, essentially the hydroxylation of the alkyl side chain (at C17) was observed, with preference for the 25-position. The entry of the steroid ring system into the substrate channel of the UPOs was found to be energetically penalized, in particular when the C3 position was already oxyfunctionalized. In consequence, substrates, such as testosterone or androstenedione, which are lacking an alkyl side chain or bearing an oxidized C3, were not converted (Babot et al., 2015a). As key finding of this approach, cholesterol (10) turned out to be completely convertible into 25-hydroxycholesterol (11, Fig. 18.8), a derivative that displays an array of pharmacological effects in vitro and in cell-based systems (Diczfalusy, 2013).
Membrane Systems
Published in Agis F. Kydonieus, Controlled Release Technologies: Methods, Theory, and Applications, 2019
The administration of the male hormone, testosterone, to rats was investigated early in the development of silicone-rubber delivery technology,97 but several years elapsed before it was evaluated in the clinic.98 While work was underway elsewhere oriented toward therapeutic or contraceptive administration of testosterone to humans, PDMS-membrane-controlled delivery of testosterone was recognized as having potential value to inhibit estrus, heat, in the canine bitch. Simmons and Hamner99 used tubing with a wall thickness of 0.65 mm to release testosterone, or androstenedione, subcutaneously. A dose of 170 µg/kg/day or more of testosterone was observed to inhibit estrus throughout studies lasting up to 28 months. Reversibility was demonstrated by whelping healthy pups after withdrawal of the implants. Androstenedione was ineffective at the delivery rates tested. The steroids were simply packed into the tubing, and released in vivo at rates (measured by difference) between 28% and 185% of the release rate anticipated on the basis of literature data.58 Masculinization in anatomy, but not behavior, was reported. The development of similar products for inhibition of estrus in pet animals appears to be approaching commercialization.
Evaluation of Food and Food Contaminants
Published in William J. Rea, Kalpana D. Patel, Reversibility of Chronic Disease and Hypersensitivity, Volume 5, 2017
William J. Rea, Kalpana D. Patel
There is controversial evidence that the widely used herbicide atrazine (ATZ) may alter gonadal development by affecting gonadal steroidogenesis through alteration of aromatase activity.351 Aromatase (cyp19) is a cytochrome P450 enzyme that converts testosterone into estradiol352 and androstenedione into estrone.353 In numerous fish, reptile, and amphibian species, cyp19 induction or inhibition produces female-biased or male-biased sex ratios, respectively.354–356 Induction of in vitro cyp19 activity has been reported in human cell lines after exposure to ATZ.357,358 However, several other studies have not observed such responses in amphibians.359–362 The underlying reasons for these differences and the mechanism through which ATZ may disrupt vertebrate development remain unclear.
A case-control study of polychlorinated biphenyl association with metabolic and hormonal outcomes in polycystic ovary syndrome
Published in Journal of Environmental Science and Health, Part C, 2022
Edwina Brennan, Nitya Kumar, Daniel S. Drage, Thomas K. Cunningham, Thozhukat Sathyapalan, Jochen F. Mueller, Stephen L. Atkin
The association between the mono-ortho dioxin like PCB, PCB118, and SHBG in this study is consistent with that found in cord blood samples from mother–child pairs in a Japanese cohort.37 The lack of association in PCOS cases may be a consequence of the relatively small number of PCOS cases (n = 27) with measured SHBG levels in addition to the significantly lower SHBG levels in cases compared to controls; 51.38 versus 109.73 nmol/L, p = .042. Conversely, there may be no association when PCOS are matched by weight and age with controls. The lower SHBG levels observed in PCOS cases is consistent with systematic review and meta-analysis of 39 studies where lower SHBG levels were associated with increased risk of PCOS (SMD: −0.83, 95% CI:–1.01, −0.64).38 Although not associated, we did find that lnPCB153, lnPCB180, and ln∑PCB correlated with increasing lnSHBG, consistent with PCB and SHBG levels in cord blood samples in the PELAGIE birth cohort.39 SHBG is known to affect the bioavailability of steroid hormones by preferential binding in the order of testosterone > androstenedione > estradiol with total testosterone represented by 1–2% circulating as free testosterone, 65% bound to SHBG, and the remaining bound to albumin.40 Given that SHBG concentrations influence testosterone concentrations, higher SHBG levels may have elevated total testosterone but low bioavailable and free testosterone concentrations,40 indicating an indirect effect of PCBs on testosterone levels.
Occurrence and fate of pharmaceuticals in effluent and sludge from a wastewater treatment plant in Brazil
Published in Environmental Technology, 2021
Ramiro Pereira Bisognin, Delmira Beatriz Wolff, Elvis Carissimi, Osmar Damian Prestes, Renato Zanella
Pharmaceuticals of human and veterinary prescription, and hormones were the assessed analytes, among them one finds β-estradiol; paracetamol; megestrol acetate; androstenedione; caffeine; ciprofloxacin; clindamycin; chloramphenicol; chlortetracycline; danofloxacin; diclofenac; doxycycline; enrofloxacin; estriol; estrone; ethisterone; fenbendazole; fenbendazole sulfone; florfenicol; flunixin; ivermectin; lincomycin; marbofloxacin; metronidazole; norfloxacin; ofloxacin; oxytetracycline; progesterone; sarafloxacin; sulfacloropyridazine; sulfadiazine; sulfadimethoxine; sulfadoxine; sulfamazine; sulfamethoxazole; sulfaquinoxalin; sulfathiazole; testosterone; tetracycline; tilmicosin; tylosin and trimethoprim. Solid analyte standards (purity ranging from 95.0 to 99.6%) were purchased from Dr. Ehrenstorfer (Germany) and Witega (Germany). The standard solution of each analyte was prepared at a concentration of 1,000 mg L−1 in acetonitrile. Afterwards, a solution encompassing a mixture of all compounds (each with 10 mg L−1) was prepared at acetonitrile. These solutions were stored in amber bottles at ± 5°C.
Human exposure to synthetic endocrine disrupting chemicals (S-EDCs) is generally negligible as compared to natural compounds with higher or comparable endocrine activity. How to evaluate the risk of the S-EDCs?
Published in Journal of Toxicology and Environmental Health, Part A, 2020
Herman Autrup, Frank A. Barile, Sir Colin Berry, Bas J. Blaauboer, Alan Boobis, Herrmann Bolt, Christopher J. Borgert, Wolfgang Dekant, Daniel Dietrich, Jose L. Domingo, Gio Batta Gori, Helmut Greim, Jan Hengstler, Sam Kacew, Hans Marquardt, Olavi Pelkonen, Kai Savolainen, Pat Heslop-Harrison, Nico P. Vermeulen
Although binding to the sex-hormone-binding-globulin may be relatively greater for the endogenous hormones than for N-EDCs and S-EDCs, it must be recognized that hormones are not the only endogenous ligands for hormone receptors. For example, dehydroepiandrosterone (DHEA) and its metabolites DHEA-sulfate, androstenedione, and androstenediol are endogenous, naturally occurring products of human metabolism that exhibit greater affinity and efficacy for the estrogen receptor than most chemicals claimed to be S-EDCs. These natural ligands are present in the blood at concentrations far greater than S-EDCs with concentrations ranging from picomolar to almost micromolar (Miller et al. 2013). Because of their affinity and high concentration in the body, these natural, endogenous ligands would occupy a significant fraction of any estrogen receptors not occupied by the endogenous hormones. Natural ligands also exist for other hormone receptors.