Attività estrogenica in bambine affette da pubertà precoce: un possibile biomarcatore di esposizione a interferenti endocrini nella vita quotidiana

Puberty is a complex process triggered and regulated by hormones, but also influenced by genetic factors, cultural factors and eating habits. In the last decades in Europe has been registered an increased incidence of puberty diseases. Although this phenomenon may be partly due to the Secular Trend, as well as to an increase in the condition of well-being, also the exposure to EDCs can be identified as a potential risk factor. Indeed, EDCs can interfere with normal pubertal development by causing precocious or more rarely delayed onset of pubertal signs. However, the evidence for the association between EDC exposure and puberty disorders in humans is still limited. The aims of the thesis were i) to investigate the possible relationship between PP and potential risk factors (e.g. exposure to EDCs in daily life, occupational EDC exposure of parents, eating habits), ii) to evaluate the potential application of an in vitro assay, specifically the gene reporter luciferase assay, as a biomarker of exposure to EDCs. This thesis is part of a case-control study approved by the Institutional Review Board of the A.O.U. Città della Salute e della Scienza di Torino - A.O. Ordine Mauriziano - A.S.L. Città di Torino which involved 40 girls aged between 3 and 9 years. The subjects were recruited from the Regina Margherita Paediatric Hospital of Turin in two sampling periods in 2018 and 2021. The parents of girls provided written consent before the study. Girls under the age of 9 with a positive diagnosis of Precocious Puberty (PP) confirmed during their access to the Department of Paediatric Endocrinology were included in the "Cases" group (n = 30), while age-matched girls not affected by endocrinology diseases were included in the "Controls" group (n = 10). In order to collect information on the study population and to evaluate the association between PP and potential risk factors for this pathology (e.g. exposure to EDCs in daily life, occupational EDC exposure of parents, eating habits), questionnaires were distributed to girls’ parents. The data were statistically analysed to highlight potential risk factors that may have increased the chance of developing the disease. Moreover, in order to evaluate the potential application of an in vitro assay as a biomarker of exposure to EDCs, blood samples were collected. In particular, serum samples were analysed through a chemiluminescence immunoassay to quantify E2, while a gene reporter luciferase assay was applied in order to assess the estrogenic activity of samples as a biomarker of exposure to EDCs. The collection of completed questionnaires, as well as the collection of serum samples and the E2 quantification, was carried out by the staff of the Regina Margherita Paediatric Hospital, while we assessed the estrogenic activity of serum samples and analysed all the collected data.