COCAINE-INDUCED EPIGENETIC REPROGRAMMING IN MALE GERM CELLS AND THE ROLE OF DRD1: CHANGES IN EPIGENETIC ENZYMES PROFILES AND TARGET HISTONE MARKS WITH FUNCTIONAL IMPLICATIONS

GASTON BARBERO; SAHIRA A. JANEIR GARAZATUA; MAXIMILIANO DE SOUSA SERRO; CAMILA PEREZ LUJAN; ALFREDO D. VITULLO; CANDELA R. GONZALEZ; BETINA GONZALEZ

Congreso; Reunion Anual de Sociedades de Biociencia 2022; 2022

Spermatogenesis presents windows of vulnerability for epigenetic reprogramming by environmental stressors that transmit developmental, metabolic, and behavioral traits to offspring. We previously demonstrated that cocaine (coc) administration downregulated dopamine receptors DRD1/2 and increased acetylated histone (H) protein levels in male germ cells (GC). Here, we analyzed specific post-translational modifications (PTMs) of H and epigenetic enzymes in isolated mouse GC treated with coc (10mg/kg) or vehicle (veh) in an intermittent binge protocol (3i.p. injections, 1h apart, one day on/off for 13 days). To evaluate the involvement of DRD1 in the deleterious action of coc, DRD1 antagonist SCH23390 (SCH 0.05mg/kg) was injected 15 min before each coc/veh injection. Additionally, we curated transcriptomic data from spermatogonia to mature sperm populations and analyzed the expression profile of writers and erasers of H lysine (K) acetylation and methylation, which act as mediators of epigenetic reprogramming events. GC from coc-treated mice showed increased H3K9me3/H3K27me3 silenced chromatin marks and decreased H3K27ac/H3K4me3 active promoter/enhancer marks. Coc also increased levels of H3K9ac/H4K16ac, involved in the replacement of H by protamines. Coc altered protein levels of LSD1 demethylase, G9A methyltransferase, MOF acetylase and HDAC1/2 and SIRT1 deacetylases. Pretreatment with SCH reversed the effects of coc on H3K4me3/H3K27me3/H4K16ac and restored HDAC1/2, SIRT1 and MOF levels. We also identified epigenetic enzymes with known functions during spermatogenesis and by the rule of “guilty by association”, many others not even described yet in GC development. We provide evidence that coc alters specific H PTMs and that DRD1 is able to mediate epigenetic changes. Moreover, some of the enzymes’ mRNAs were detected in mature sperm, suggesting a paternal contribution to the zygote. Our study contributes to the mechanistic aspects behind transgenerational epigenetics.