Summary: Researchers report that piglets born to mothers fed a choline-rich diet showed increases in both white and gray matter in the brain.
Source: University of Illinois.
Maternal choline intake during pregnancy can shape infant metabolism and brain development, according to a series of studies from the University of Illinois. While prior research on choline’s role in neurodevelopment relied heavily on rodent models, these new pig studies offer stronger translational relevance to humans.
“The pig is a useful model for human development because pigs share nutrient requirements, similar metabolic functions, and comparable brain growth trajectories,” explains Austin Mudd, a doctoral student in the Neuroscience Program at the University of Illinois. “Pigs help bridge the gap between mechanistic rodent studies and higher-level human cognitive research.”
Choline is an essential dietary nutrient found in foods such as liver, eggs, and wheat germ. It is required for building cell membranes, producing neurotransmitters, and forming myelin, the fatty insulation that surrounds nerve fibers. Despite its importance, many adults—including pregnant women—consume less choline than recommended.
“In the U.S., about 90 percent of people do not meet their choline requirement,” Mudd says. “Pregnant women, who are advised to consume 450 milligrams per day, often fall well short—sometimes below 300 milligrams.”
To examine how choline availability affects the developing brain, Mudd and colleagues provided pregnant sows with either choline-sufficient or choline-deficient diets during the second half of gestation. After birth and weaning, piglets were assigned to either choline-sufficient or choline-deficient milk replacers for 28–30 days. At about one month of age, the piglets underwent magnetic resonance imaging (MRI) to assess brain structure.
The team performed multiple analyses of the MRI scans. An initial analysis, reported in 2016, compared volumes across 19 brain regions between animals exposed to prenatal and postnatal choline conditions. A later analysis published in Current Developments in Nutrition refined those findings by controlling for overall volume differences and focusing on localized concentrations of gray and white matter.
“Piglets from mothers fed choline-deficient diets had brains that were roughly 10 percent smaller overall,” Mudd reports, and 11 of the 19 examined regions were significantly reduced in volume in those animals.
When the researchers adjusted for volume to look specifically at tissue composition, the pattern persisted. Piglets whose mothers consumed adequate choline during pregnancy showed higher concentrations of gray and white matter in cortical regions compared to piglets from choline-deficient mothers.
Gray matter largely consists of neuronal cell bodies, while white matter is composed of the myelinated fibers that connect different brain regions. “In our first study we observed larger left and right cortical volumes in choline-sufficient pigs,” Mudd says. “The increased gray matter density we found in the follow-up analysis explains that volume difference.”
Longstanding nutrition research shows that specific nutrients exert broad effects on brain development. Non-invasive MRI techniques now allow scientists to identify how single nutrients influence particular aspects of brain structure. For example, earlier work by the same group showed that iron also affects gray and white matter development.
“Our findings indicate choline, much like iron, supports multiple facets of brain development rather than a single isolated process,” Mudd adds.
The studies also tested whether postnatal choline supplementation could reverse the effects of prenatal deficiency. The short answer for brain structure is no. “Postnatal supplementation cannot fully correct a prenatal deficiency. The critical window for those neural changes is during prenatal development,” says Ryan Dilger, associate professor in the Department of Animal Sciences and the Neuroscience Program at the University of Illinois.
However, earlier work by graduate researcher Caitlyn Getty on the same cohort of piglets examined overall health and metabolism and found that postnatal choline did matter for peripheral organs. Getty’s 2015 study reported lower brain weights in piglets from choline-deficient mothers and highlighted the importance of postnatal choline for liver and kidney function.
Collectively, these results support a cellular-level mechanism consistent with human epidemiological findings. A 2013 human study reported that children born to mothers with low choline intake scored lower in academic measures by age seven. Structural brain differences present early in life may not produce immediately obvious functional changes but can influence later cognitive outcomes.
“Structural alterations are present from development, but their consequences may not appear until later,” Mudd notes. “That’s why ensuring adequate choline during pregnancy is important: the changes occur during gestation.”
Dilger emphasizes the subtlety of the effect: “This is not evidence of an overt developmental disorder or a single food causing a condition. Rather, these findings point to small sources of individual variation that could be tied to maternal diet during pregnancy.”
Funding: This research was funded by the USDA National Institute of Food and Agriculture.
Source: Lauren Quinn, University of Illinois
Publisher: Organized by NeuroscienceNews.com
Image Source: Public domain image used by NeuroscienceNews.com.
Original Research: Open access study “Maternal Dietary Choline Status Influences Brain Grey and White Matter Development in Young Pigs” by Austin T. Mudd, Caitlyn M. Getty, and Ryan N. Dilger, published in Current Developments in Nutrition, online March 21, 2018.
doi: 10.1093/cdn/nzy015
MLA: University of Illinois. “Prenatal Choline Intake Increases Gray and White Matter: Piglet Study.” NeuroscienceNews, 27 March 2018.
APA: University of Illinois (2018, March 27). Prenatal Choline Intake Increases Gray and White Matter: Piglet Study. NeuroscienceNews. Retrieved March 27, 2018.
Chicago: University of Illinois. “Prenatal Choline Intake Increases Gray and White Matter: Piglet Study.” Accessed March 27, 2018.
Abstract
Maternal Dietary Choline Status Influences Brain Grey and White Matter Development in Young Pigs
Background
Choline is an essential nutrient critical for healthy brain development. Animal studies indicate that perinatal choline deficiency affects neuron development in the hippocampus and cortex, but many of those observations relied on invasive methods.
Objective
This study used non-invasive neuroimaging in young pigs to characterize how perinatal choline deficiency alters gray and white matter development.
Methods
During the final 64 days of a 114-day gestation period, Yorkshire sows received either a choline-sufficient (CS) diet or a choline-deficient (CD) diet, containing approximately 1,214 mg or 483 mg total choline per kg of diet, respectively. After birth, piglets received colostrum for up to 48 hours, were assigned to postnatal treatment groups, and were fed either CS or CD milk replacers (approximately 1,591 mg or 518 mg total choline per kg, respectively) for 28 days. At 30 days of age, pigs underwent MRI. Gray and white matter development were assessed via voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) to evaluate prenatal and postnatal choline effects.
Results
VBM revealed that prenatally choline-sufficient pigs had significantly increased gray matter in the left and right cortex and increased white matter in the internal capsule, putamen-globus pallidus, and right cortex compared with prenatally choline-deficient pigs (P < 0.01). No significant postnatal effects were detected in the VBM analyses, and TBSS found no significant prenatal or postnatal effects on diffusion measures along white matter tracts (P > 0.05).
Conclusions
Prenatal choline deficiency is associated with altered cortical gray matter and reduced white matter in specific subcortical regions in young pigs. These non-invasive imaging results suggest that prenatal choline status substantially influences brain tissue development and offer translational insight relevant to clinical populations.