Longevity
Naked mole rats may shuttle fat out of brain cells to avoid damage, mouse study finds
By Life and Health Today Staff, . Life and Health Today.
Researchers at the University of Oslo have published findings in GeroScience suggesting that naked mole rats handle fat accumulation in their brain cells differently from mice, in a way that may protect neurons from damage as the animals age.
The naked mole rat (Heterocephalus glaber) is a small, burrowing rodent native to eastern Africa. It is the longest-lived rodent known, capable of reaching close to 40 years in captivity, according to GeroScience, and it does not appear to develop the cancers, cardiovascular disease, or neurodegeneration that shorten the lives of most mammals of comparable size.
The study focused on lipid droplets, which are small structures inside cells that store neutral fats such as cholesterol esters and triglycerides. In recent years, researchers have identified a type of brain immune cell called a microglial cell that accumulates lipid droplets with age in both mice and humans, and some scientists have proposed that these fat-laden microglia contribute to neurodegeneration. Other researchers have argued the opposite: that moving fat from neurons into glial cells is a protective act, shielding neurons from a toxic buildup of lipids. GeroScience notes that the literature is currently conflicted on this point.
To investigate, the Oslo team examined coronal brain sections from four young and four middle-aged naked mole rats (approximately 4 and 13 years old respectively) and from four young and four middle-aged mice (26 weeks and 52 to 54 weeks old), with each group containing two females and two males among the mole rats, and three females and one male among the mice. They used fluorescent dyes and imaging techniques to identify lipid droplets in neurons and in microglia within the hippocampus, the brain region most associated with memory.
In the naked mole rats, microglia in the hippocampus contained large amounts of lipid droplets, and the number increased with age specifically in the CA3 region of the hippocampus. Crucially, the size of lipid droplets inside neurons did not change with age in the naked mole rats. In mice, the pattern was reversed: microglia held fewer lipid droplets and showed no age-related change, while neuronal lipid droplet size increased with age in the same CA3 region.
The researchers interpret this as possible evidence of two different strategies. In the naked mole rat, lipids may be actively transferred from neurons to microglia, preventing a toxic buildup inside the neurons themselves. In mice, that transfer appears not to happen, and fat accumulates in the neurons instead. The authors describe this as a potential protective mechanism that could contribute to the naked mole rat's unusual resistance to brain disease. That interpretation is the researchers' hypothesis, not an established mechanism: the study observed a pattern in a small number of animals; it did not directly demonstrate that lipid transfer is occurring or that it causes the longevity advantage.
The study also found that the naked mole rat brain has lower vascularization, meaning fewer blood vessels, than the mouse brain in several regions. The authors suggest this fits with the animal's known low metabolic rate and its documented ability to survive up to 18 minutes of complete oxygen deprivation without apparent brain damage.
What this does not show is whether anything similar happens in human brains, or whether the mechanism could be influenced by any intervention. The sample sizes were small, the full text of the paper as published by GeroScience was not available in its entirety, and the authors' own stated limitations were not visible in the portion reviewed. The open question is whether the lipid-shuttling pattern the researchers observed is a cause of the naked mole rat's longevity, a consequence of some other biological difference, or both. Answering that would require experiments that directly manipulate the transfer process and observe what follows, work that has not yet been done.
For anyone interested in brain ageing, this is a finding worth watching at the preclinical stage. Whether it points toward anything actionable for people is a question that remains entirely open.
Source: https://link.springer.com/article/10.1007/s11357-026-02548-6