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Effect of selected perfumes on aromatase activity
Drejslarová, Iva ; Hodek, Petr (advisor) ; Smrček, Stanislav (referee)
Cytochromes P450 are enzymes involved in many physiological processes in the body, besides the metabolism of xenobiotics also in the biosynthesis and catabolism of endogenous substances such as hormones and steroids. Cytochromes P450 that are responsible for the transformation of endogenous compounds can be affected by xenobiotics, which interfere with the secretion, metabolism, transport or elimination of endogenous hormones by various mechanisms. These substances are also referred to as endocrine disruptors and include, for example, pesticides, insecticides, certain pharmaceuticals, or compounds contained in cosmetic products. One of their mechanisms of action is to interfere with steroid hormone biosynthesis through interactions with steroidogenic enzymes. One such enzyme is cytochrome P450 19, aromatase, which catalyses the conversion of testosterone to ß-estradiol in the final step of steroid hormone biosynthesis. Modulation of the activity of this enzyme by endocrine disruptors results in an imbalance of estrogen levels in the body, which can lead to impaired reproduction, osteoporosis, atherosclerosis, dementia, and the development of certain types of cancer. In this context, the effect of commercially available perfumes on the conversion of testosterone to ß-estradiol, which is catalyzed by...
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Effect of selected cosmetic products on estrogen formation
Drejslarová, Iva ; Hodek, Petr (advisor) ; Smrček, Stanislav (referee)
Cytochrome P450 enzymes play a key role in the metabolism of endogenous and exogenous compounds. These enzymes are involved both in biotransformation and steroid hormone biosynthesis. An important member of this family is cytochrome P450 19, aromatase, which catalyzes the final step of estrogen hormone biosynthesis, conversion of androgens into estrogens. The physiologic functions of estrogens include development of secondary sexual characteristicts, maintenance of bone mass or regulation of gonadotropin secretion. However, hormonal imbalance due to endocrine disruptors can result in development of certain cancers or impaired reproduction. Compounds with these effects include, in addition to environmetal pollutants, some drugs and cosmetic additives which people are exposed to on a daily basis. In the present study, the effect of selected perfumes and antiperspirants on the metabolic conversion of testosterone into estradiol, catalyzed by aromatase, was examined. The activity of this enzyme was detected using TLC chromatography. The experiments showed that selected antiperspirants do not affect aromatase activity. For most of the perfumes tested, only a very low aromatase inhibition was observed. Only one sample showed this effect to a higher extent. Based on the comparision of perfume...
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