Proteomic Analysis of Baboon Cerebral Artery Reveals Potential Pathways of Damage by Prenatal Alcohol Exposure*

Abstract

In BriefProteome analysis was performed to determine whether fetal alcohol exposure during mid-pregnancy would evoke changes in protein profile of fetal cerebral artery in baboons. We detected that levels of 238 proteins differed significantly between control and alcoholexposed fetuses. Proteins of metabolic pathways represented one of the major targets of alcohol. The differences were detected near term, long after alcohol exposure took place. Our findings point at novel targets of alcohol within developing brain vessels. Graphical Abstract Highlights• We studied mid-pregnancy alcohol exposure and baboon fetal cerebral artery.• 238 proteins differed between control and alcohol-exposed fetuses near-term.• Proteins of metabolic pathways represented one of the major targets of alcohol.• Alcohol effect on the development of fetal brain vessels is persistent.Alcohol is one of the most widely misused substances in the world. Alcohol consumption by pregnant women often results in an array of fetal developmental abnormalities, but the damage to the fetus by alcohol remains poorly understood. The limited knowledge regarding the molecular targets of alcohol in the developing fetus constitutes one of the major obstacles in developing effective pharmacological interventions that could prevent fetal damage after alcohol consumption by pregnant women. The fetal cerebral artery is emerging as an important mediator of fetal cerebral damage by maternal alcohol drinking. In the present work, we conduct proteomics analysis of cerebral (basilar) artery lysates of near-term fetal baboons to search for protein targets of fetal alcohol exposure. Our study demonstrates that 3 episodes of binge alcohol exposure during the second trimester-equivalent of human pregnancy are sufficient to render profound changes in fetal cerebral artery proteome. These changes persisted, as they were detected in near-term fetuses. In particular, the relative abundance of 238 proteins differed significantly between control and alcohol-exposed fetuses. Enrichment analysis pointed at the group of metabolic activity proteins as a major class targeted by alcohol. Western blotting confirmed upregulation of the aldehyde dehydrogenase 6 family member A1 (ALDH6A1) in cerebral artery lysates from alcohol-exposed fetuses. This upregulation translated to greater ALDH activity of cerebral artery lysate of near-term fetuses following prenatal alcohol exposure when compared with controls. Molecular

Fetal Cerebral Artery Mitochondrion as Target of Prenatal Alcohol Exposure

“…Within cerebral arteries, mitochondria control a plethora of cellular processes, including apoptosis [62,63], maintenance of arterial tone, constrictive or dilatory responses to physiological/pharmacological stimuli, adaptation to environmental insult [27,30,43,64], and vascular aging [65,66]. Indeed, mitochondrial size is increased with age, as reported for vascular smooth muscle of 3 versus 18 months-old Sprague–Dawley rats [67].…”

“…Both ADH and two isozymes of ALDH (ALDH-I and ALDH-II-NAD+) are detected in rat liver samples as early as 5 days before birth [89]. This time window corresponds to the end of the second trimester in humans [90], which is close to the time-window for the detection of ALDH6A1 expression and functional activity in fetal baboon cerebral arteries [27]. Moreover, in the perinatal period, a remarkable increase in rat fetal liver ALDH activity is noted in the mitochondrial fraction [91].…”

“…The control group of pregnant baboons receives three gastric infusions of orange-flavored drink that matches caloric count of alcohol-containing infusion liquid. Fetuses are delivered by cesarean section near-term at 165 days of gestation, and fetal basilar (cerebral) arteries are harvested for differential protein expression (proteomics) analysis [27]. Of note, the basilar artery participates in irrigation of the cerebellum that constitutes a rather sensitive target for prenatal alcohol exposure.…”

“…Differential protein expression analysis based on mass spectroscopy identification reveals statistically significant differences in the relative abundance of 238 proteins between control and alcohol-exposed fetal basilar arteries [27]. Statistical enrichment analysis points to the statistically significant overrepresentation of mitochondria-related proteins within this set.…”

“…Within the cells, mitochondria constantly power adaptation to dynamic changes in metabolic demands. Thus, it comes as no surprise that vascular mitochondria dysfunction is implicated in the progressive decline observed during aging, development of neurocognitive disorders (such as Alzheimer’s disease), and substance abuse [23,24,25,26,27]. The deleterious effects of alcohol exposure on mitochondrial morphology and function within fetal tissues have been widely documented [28].…”