Brain mapping efforts are shifting focus toward lipids, highlighted by a new spatial atlas published in Nature and a July study in Science Advances tracking temporal lipid changes in quiescent neural stem cells as mice age, according to recent neuroscience reports.
While brain mapping has long been dominated by transcriptomics and connectomics, researchers are increasingly turning their attention to the lipids that make up cell membranes, organelles, and nuclei. According to a new atlas described in Nature, the spatial distribution of 172 membrane lipids across 109 brain sections from 11 mice has been mapped with unprecedented resolution.
Lipizones Reveal Complex Brain Architecture Beyond Gene Expression
The mapping reveals that lipids cluster into 539 distinct regions known as “lipizones,” painting a picture of brain structure that is as intricate as gene expression maps. Using mass spectrometry imaging, researchers found that this lipid map does not align neatly with RNA expression maps of lipid-producing enzymes, metabolism-related genes, or the full Allen Brain Atlas transcriptome.
During the early stages of his doctorate, École Polytechnique Fédérale de Lausanne assistant professor and Nature atlas researcher Gioele La Manno recalled anticipating that cellular modifications would invariably show up in RNA. Later, however, his team observed 14 distinct lipizones in a cortical region involved in fine-grained whisker sensation that could not be distinguished by transcriptomics alone.
You cannot, simply by looking at gene expression, understand the story.
Gioele La Manno, École Polytechnique Fédérale de Lausanne
La Manno added that the new map reveals a shadow of connectivity
driven by the myelin sheaths of long-range neurons, allowing scientists to observe neural connectivity in previously unachievable ways.
Cellular Aging and the Role of Polyunsaturated Fatty Acids
A separate study published in July in Science Advances tracked temporal changes in brain lipids, focusing on quiescent neural stem cells—cells existing in a reversible state of nonproliferation. As mice age, these cells shift toward lipids featuring highly unsaturated polyunsaturated fatty acid (PUFA) side chains, resulting in less ordered membranes.
According to study investigator Xiaoai Zhao, assistant professor of comparative medicine at Yale School of Medicine, This could be related to their functional decline
. Zhao and her team also found that specific enzymes tracking with these age-related shifts either remodel PUFA side chains, show high expression in quiescent neural stem cells, or experience significant expression changes over time.
Bruce Cohen, the Robertson-Steele Professor of Psychiatry at Harvard Medical School, who did not participate in either investigation, explained how the discoveries change the field of neuroscience.
Anything that goes on with a cell goes across a membrane, along a membrane, within a membrane. Most of us aren’t adequately exposed to the importance of lipids, and we should be.
Bruce Cohen, Harvard Medical School
Pregnancy Causes Greater Brain Lipid Shifts than Sex Differences
The research also sheds light on how physiological states impact brain lipids. Comparisons between male and female mice showed that sex differences were less dramatic than the shifts observed between mid-gestation pregnant females and nonpregnant females.
