NEONICOTINOIDS EFFECTS ON DNA METHYLATION AND SIRTUIN EXPRESSION IN HUMAN PLACENTA EXPLANTS

SANCHEZ CABRERA AZUL; VERA BERTA; FARINA MARIANA; GUIÑAZÚ NATALIA; SONGZONI SILVINA

Mar del Plata

Congreso; Reunión anual de sociedades de biociencias; 2023

Sociedad Argentina de Investigación Clínica

Argentina's apple and pear production is centered in the Alto Valle of Rio Negro and Neuquén. This production relies on the intensive application of pesticides, such as Neonicotinoids (NEO). Pregnancy is proposed as the first exposure scenario in human life, as environmental chemicals can access the placenta and affect its function. Recently, the exposure to pesticides has been associated with epigenetic alterations, which can affect the expression of various genes. The study aimed to explore epigenetic alterations caused by NEO exposure in human placenta explant cultures, focusing on the expression of DNA methylation enzymes and sirtuins (Sirts), histone deacetylase proteins. Explants were obtained from normal-term pregnancies and exposed to the NEO Acetamiprid (Ace) and a commercial formulation (AceCF) at concentrations ranging from 0.1 to 10 µM for 24 h. To ensure the explants’ functionality and viability, MTT (Thiazolyl Blue Tetrazolium Bromide), LDH (Lactate Dehydrogenase) and hCG (chorionic gonadotropin) assays were conducted. Ten-Eleven-Translocation enzymes TET2, TET3 and DNA methyltransferase DNMT3A, DNMT3B and Sirts 1, 2, 4, and 5 expressions were studied by qPCR. After 24h of NEO treatment, explants remained viable, as indicated by no significant changes in MTT, LDH, and hCG tests (One-way ANOVA p>0.05), suggesting the suitability of the explants for evaluating molecular NEO toxicity. The expression of DNA methylation enzymes TET2, TET3, and DNMT3A remained unchanged, while DNMT3B levels were increased in Ace treatments starting from 1 µM concentration and in AceCF starting from 0.1µM. Sirt 1, 4, and 5 showed a 60% decrease with Ace, and AceCF exhibited a 50% reduction at the lowest concentration before returning to baseline. Sirt 2 expression was undetectable for both pesticides. In summary, this preliminary study presents the first evidence of epigenetic changes associated with NEO exposure, suggesting potential disruption of several cellular processes.