Prenatal alcohol exposure has been shown to increase the probability of use and abuse of ethanol later in life. One question remaining to be answered is, can it also be transmitted across generations? Our data suggest that low/moderate ethanol exposure results in increased ethanol intake and reduced sensitivity to ethanol's hypnotic effects during puberty not only in those infant rats exposed to ethanol in the womb but also in their offspring. Our central hypothesis is that inheritance of ethanol use/abuse liability s transgenerational and associated with variations in DNA methylation in specific brain regions known to be involved in alcohols rewarding proper- ties. The transformative objective of the present proposal is to identify the specific genes in these brain areas that are involved in ethanol programming as well as the lineage involved in transgenerational transmission of the ethanol-exposed phenotype. This project uses an animal model of prenatal ethanol exposure to investigate the transmission of increased liability for ethanol abuse in the offspring directly exposed to alcohol in the womb and their progeny.
Specific Aim 1 will determine the contribution of maternal and paternal lineages in the effect of gestational ethanol exposure on ethanol sensitivity and consumption in three generation of off- spring. This will be achieved through testing prenatally exposed animals and breeding male and female rats prenatally exposed (F1) to 1) ethanol, 2) water, or 3) non-manipulated in all possible combinations (9; see table in approach) to determine the lineage involved in transmission. Our hypothesis, that inheritance is through paternal lineage, will be tested by examining ethanol intake at postnatal day (PD) 14 and in adolescence, and sensitivity to the hypnotic effects (loss of righting reflex test) of ethanl at PD 42.
Specific Aim 2 will identify the effect of ethanol exposure during gestation on genome-wide DNA methylation of F1 and F2 of the extreme lineage (affected lineage and control), using a whole-genome bisulfate sequencing technique. Results obtained after completion of this work will allow us to direct future work towards target genes involved in the transmission of ethanol-exposed phenotype, and to better understand the mechanisms involved in transgenerational inheritance of increased risk for ethanol abuse.
Exposure to alcohol early in life is a major contributing factor to future use and abuse of the drug. Epigenetics and trans-generational inheritance has recently become a point of focus. The epigenetic changes brought about by ethanol may be passed on trans-generationally as seen in our preliminary data. The proposed experiments will delineate, not only the germ line via which these changes occur, but also look at changes in DNA methylation due to prenatal ethanol exposure.
| Popoola, Daniel O; Cameron, Nicole M (2018) Maternal care-related differences in males and females rats' sensitivity to ethanol and the associations between the GABAergic system and steroids in males. Dev Psychobiol 60:380-394 |
| Popoola, Daniel O; Nizhnikov, Michael E; Cameron, Nicole M (2017) Strain-specific programming of prenatal ethanol exposure across generations. Alcohol 60:191-199 |
