Vrednotenje halogeniranih parabenov, bisfenolov in UV-filtrov kot modulatorjev tiroidnega receptorja in vitro

Jud, Nuša (author), Gobec, Martina (mentor), Weiss, Veronika (comentor)

Tekom življenja smo ljudje izpostavljeni različnim kemikalijam. Z vsakodnevno uporabo izdelkov za osebno nego in gospodinjstvo, lahko vstopijo v človeško telo na različne načine in predstavljajo tveganje za naše zdravje. Primeri takih skupin kemikalij so: (i) parabeni, ki se uporabljajo kot konzervansi v različnih kozmetičnih, farmacevtskih in prehranskih izdelkih; (ii) bisfenoli, ki se široko uporabljajo v proizvodnji plastike; (iii) UV filtri, ki se uporabljajo v izdelkih za zaščito pred soncem; in (iv) alkilfenol etoksilati, ki se uporabljajo kot neionske površinsko aktivne snovi. Te kemikalije se neprestano izločajo v okolje in se tako v čistilnih napravah za odpadno vodo kot v čistilnih napravah za pitno vodo pretvorijo do halogeniranih produktov. Zaradi svoje strukture bi se halogenirani derivati lahko vezali na tiroidne receptorje in tako delovali kot hormonski motilci. V diplomski nalogi smo preučevali vpliv halogeniranih parabenov, bisfenolov, UV filtrov in alkilfenol etoksilatov na tiroidni receptor, izražen v poročevalski celični liniji GH3.TRE-Luc. Najprej smo opravili test presnovne aktivnosti, da smo določili ne-citotoksične koncentracije izbranih spojin. Slednje smo nato vrednotili kot morebitne modulatorje tiroidnega receptorja z luciferaznim testom pri 10 µM koncentraciji. Luciferazni test vrednoti učinke spojin na tarčnem receptorju preko nivoja izražanja proteina luciferaza. Nivo slednjega se lahko poviša, v kolikor so spojine agonisti, ali zniža, če so spojine antagonisti. Agonistični učinek na tiroidnih receptorjih, glede na rezultate naše raziskave, pri 10 µM koncentraciji izkazujejo Cl2BPE, BrBPE, ClBPF, BrBPF, 2,6-Br2BPF, 2,2'-Br2BPF, 2,6-Br2BPS in BrBP-3. Pri enaki koncentraciji so antagonistični potencial izkazale Cl2BuP, BrBuP, Br2BuP, Cl2iBuP, Br-iBuP, Br2iBuP, ClPeP, Cl2PeP, BrPeP, Br2PeP, ClBzP, Cl2BzP, BP-3, BrBMDM in BrOMC. Podrobnejše vrednotenje vpliva odmerka na modulacijo receptorja, je pokazalo, da so v agonistični seriji največjo aktivacijo receptorja dosegle spojine ClBPF, Cl2BPF, BrBPF in 2,2'-Br2BPF. V antagonistični seriji smo potrdili opažanja iz preliminarnih testiranj, saj je nadaljnje vrednotenje BuP, PeP in njunih halogeniranih derivatov pokazalo, da daljša kot je stranska veriga in višja kot je stopnja halogeniranja, večji je antagonistični učinek.

• Language: Slovenian
• Keywords: tiroidni receptor, hormonski motilci, parabeni, bisfenoli, UV filtri, alkilfenol etoksilati, GH3.TRE-Luc
• Work type: Bachelor thesis/paper
• Organization: FFA - Faculty of Pharmacy
• Year: 2024
• PID: 20.500.12556/RUL-160486
• Publication date in RUL: 29.08.2024

Secondary language

• Language: English
• Title: In vitro evaluation of halogenated parabens, bisphenols and UV filters as thyroid receptor modulators

Abstract

Throughout our lives, we are exposed to different chemicals. Through the daily use of personal care and household products, they can enter the human body in different ways and pose risk to our health. Examples of such groups of chemicals are: (i) parabens, which are used as preservatives in various cosmetic, pharmaceutical and nutritional products; (ii) bisphenols, which are widely used in the manufacture of plastics; (iii) UV filters, which are used in sunscreen products; and (iv) alkylphenol ethoxylates, which are used as non-ionic surfactants. These chemicals are continuously released into the environment and are converted to halogenated products in both waste water and drinking water treatment plants. Due to their structure, halogenated derivatives could bind to thyroid receptors and thus act as hormone disruptors. In the thesis, we researched the influence of halogenated parabens, bisphenols, UV filters and alkylphenol ethoxylates on the thyroid receptor expressed in the GH3.TRE-Luc reporter cell line. First, a metabolic activity assay was performed to determine the non-cytotoxic concentrations of selected compounds. The latter were then evaluated as potential modulators of the thyroid receptor by a luciferase assay at 10 µM concentration. The luciferase assay evaluates the effects of compounds on the target receptor via the expression level of the luciferase protein. The level of the latter can be increased if the compounds are agonists or decreased if the compounds are antagonists. The agonist effect on thyroid receptors, according to the results of our study, at a concentration of 10 µM, is exhibited by Cl2BPE, BrBPE, ClBPF, BrBPF, 2,6-Br2BPF, 2,2'-Br2BPF, 2,6-Br2BPS and BrBP-3. Antagonistic potential at the same concentration showed Cl2BuP, BrBuP, Br2BuP, Cl2iBuP, Br-iBuP, Br2iBuP, ClPeP, Cl2PeP, BrPeP, Br2PeP, ClBzP, Cl2BzP, BP-3, BrBMDM and BrOMC. A more detailed evaluation of the effect of dose on receptor modulation showed that in the agonist series, the compounds ClBPF, Cl2BPF, BrBPF and 2,2'-Br2BPF achieved the highest receptor activation. In the antagonistic series, we confirmed the observations made in the preliminary tests, as further evaluation of BuP, PeP and their halogenated derivatives showed that the longer the side chain and the higher level of halogenation, the greater the antagonistic effect.

• Keywords: thyroid receptor, hormone disruptors, parabens, bisphenols, UV filters, alkylphenol ethoxylates, GH3.TRE-Luc