Early to mid-gestational testosterone excess leads to adverse lung programming in sheep offspring

Prenatal testosterone (T) excess programs sex-specific cardiovascular dysfunction in sheep offspring. Given the close reciprocal relationship between the cardiopulmonary system, we hypothesized that prenatal T excess would also adversely program the offspring’s pulmonary system in a sex-specific manner from fetal life into adulthood. Pregnant ewes received intramuscular injections of T propionate (100 mg) or a vehicle control (C) twice weekly from gestational days (GD) 30-90 (term 147 days). Offspring lungs were collected at GD120 (n=6-7 per group), and at 24 months of age (n=4-6 per group) for histological and molecular analyses. Data were analyzed using two-way ANOVA (fetal) and/or sex-specific stratified t-tests for adults and Cohen's effect size analyses. Prenatal T significantly increased fetal lung collagen deposition in males. Prenatal T treatment had a significant overall treatment main effect on fetal lung apoptosis and the ratio of small to total blood vessels. Some adverse effects of prenatal T excess persisted into adulthood, including a significant increase in lung collagen in both sexes. Fetal lung transcriptome revealed differential enrichment of pathways involved in regulation of hormone biosynthetic process, and neuron apoptotic process in T- treated males, whereas pathways related to bicarbonate transport and regulation of muscle cell differentiation were enriched in T- treated females. Overall, early- to mid-gestational T excess adversely reprograms the offspring’s lungs in a sex-specific manner, from fetal life extending into adulthood.