Neuroactive steroids modulate alcohol's impact on brain function and behavior. Ethanol exposure alters neuroactive steroid levels in rats, humans, and some mouse strains. We conducted an exploratory analysis of the neuroactive steroids (3alpha,5alpha)-3-hydroxypregnan-20-one (3alpha,5alpha-THP), (3alpha,5alpha)-3,21-dihydroxypregnan-20-one (3alpha,5alpha-THDOC), and pregnenolone across 126-158 individuals and 19 fully inbred strains belonging to the BXD family, which were subjected to air exposure, or chronic intermittent ethanol (CIE) exposure. Neuroactive steroids were measured by gas chromatography-mass spectrometry in serum following five cycles of CIE or air exposure (CTL). Pregnenolone levels in CTLs range from 272 to 578pg/mL (strain variation of 2.1 fold with p=0.049 for strain main effect), with heritability of 0.20±0.006 (SEM), whereas in CIE cases values range from 304 to 919pg/mL (3.0-fold variation, p=0.007), with heritability of 0.23±0.005. 3alpha,5alpha-THP levels in CTLs range from 375 to 1055pg/mL (2.8-fold variation, p=0.0007), with heritability of 0.28±0.01; in CIE cases they range from 460 to 1022pg/mL (2.2-fold variation, p=0.004), with heritability of 0.23±0.005. 3alpha,5alpha-THDOC levels in CTLs range from 94 to 448pg/mL (4.8-fold variation, p=0.002), with heritability of 0.30±0.01, whereas levels in CIE cases do not differ significantly. However, global averages across all BXD strains do not differ between CTL and CIE for any of the steroids. 3alpha,5alpha-THDOC levels were lower in females than males in both groups (CTL-53%, CIE-55%, p<0.001). Suggestive quantitative trait loci are identified for pregnenolone and 3alpha,5alpha-THP levels. Genetic variation in 3alpha,5alpha-THP was not correlated with two-bottle choice ethanol consumption in CTL or CIE-exposed animals. However, individual variation in 3alpha,5alpha-THP correlated negatively with ethanol consumption in both groups. Moreover, strain variation in neuroactive steroid levels correlated with numerous behavioral phenotypes of anxiety sensitivity accessed in GeneNetwork, consistent with evidence that neuroactive steroids modulate anxiety-like behavior.
Initial genetic dissection of serum neuroactive steroids following chronic intermittent ethanol across BXD mouse strains.
Porcu P;
2017
Abstract
Neuroactive steroids modulate alcohol's impact on brain function and behavior. Ethanol exposure alters neuroactive steroid levels in rats, humans, and some mouse strains. We conducted an exploratory analysis of the neuroactive steroids (3alpha,5alpha)-3-hydroxypregnan-20-one (3alpha,5alpha-THP), (3alpha,5alpha)-3,21-dihydroxypregnan-20-one (3alpha,5alpha-THDOC), and pregnenolone across 126-158 individuals and 19 fully inbred strains belonging to the BXD family, which were subjected to air exposure, or chronic intermittent ethanol (CIE) exposure. Neuroactive steroids were measured by gas chromatography-mass spectrometry in serum following five cycles of CIE or air exposure (CTL). Pregnenolone levels in CTLs range from 272 to 578pg/mL (strain variation of 2.1 fold with p=0.049 for strain main effect), with heritability of 0.20±0.006 (SEM), whereas in CIE cases values range from 304 to 919pg/mL (3.0-fold variation, p=0.007), with heritability of 0.23±0.005. 3alpha,5alpha-THP levels in CTLs range from 375 to 1055pg/mL (2.8-fold variation, p=0.0007), with heritability of 0.28±0.01; in CIE cases they range from 460 to 1022pg/mL (2.2-fold variation, p=0.004), with heritability of 0.23±0.005. 3alpha,5alpha-THDOC levels in CTLs range from 94 to 448pg/mL (4.8-fold variation, p=0.002), with heritability of 0.30±0.01, whereas levels in CIE cases do not differ significantly. However, global averages across all BXD strains do not differ between CTL and CIE for any of the steroids. 3alpha,5alpha-THDOC levels were lower in females than males in both groups (CTL-53%, CIE-55%, p<0.001). Suggestive quantitative trait loci are identified for pregnenolone and 3alpha,5alpha-THP levels. Genetic variation in 3alpha,5alpha-THP was not correlated with two-bottle choice ethanol consumption in CTL or CIE-exposed animals. However, individual variation in 3alpha,5alpha-THP correlated negatively with ethanol consumption in both groups. Moreover, strain variation in neuroactive steroid levels correlated with numerous behavioral phenotypes of anxiety sensitivity accessed in GeneNetwork, consistent with evidence that neuroactive steroids modulate anxiety-like behavior.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
