A widely promoted anti-aging drug combination may carry significant neurological risks, according to new research in mice. Scientists report that the combination of dasatinib and quercetin (D+Q) can cause extensive damage to the brain’s myelin, the insulating sheath that surrounds and protects nerve fibers.
The study, led by researchers at the University of Connecticut and published in Proceedings of the National Academy of Sciences (PNAS), raises new concerns about the expanding use of D+Q in longevity research and experimental off-label anti-aging regimens. The damage was observed in both young and aged mice and was unexpectedly more severe in younger animals.
Senolytic Drugs Under New Scrutiny
Dasatinib, a tyrosine kinase inhibitor used to treat certain cancers, and quercetin, a naturally occurring plant flavonoid, are among the best-known senolytic compounds. Senolytics are designed to selectively eliminate senescent cells, which accumulate with age and contribute to chronic inflammation and age-related disease. By removing these dysfunctional cells, D+Q has been investigated as a potential strategy to reduce inflammation and delay age-associated disorders.
The combination has already been evaluated in small clinical trials for conditions including idiopathic pulmonary fibrosis and is currently being investigated for disorders such as type 2 diabetes and Alzheimer’s disease. At the same time, some biohackers and longevity enthusiasts have begun self-administering D+Q despite limited evidence regarding its safety, particularly its long-term effects on the central nervous system.
Myelin Loss and Structural Brain Damage
The University of Connecticut research team initially aimed to determine whether D+Q could enhance myelin repair in a mouse model of multiple sclerosis, a disease characterized by progressive myelin loss. Instead, after administering the drug combination to both young adult and aged mice, the researchers observed marked thinning and loss of myelin in otherwise healthy brain tissue.
Microscopic examination revealed that nerve fibers, which normally appear tightly wrapped in thick layers of myelin, became poorly insulated following treatment. The corpus callosum—the large bundle of nerve fibers connecting the brain’s two hemispheres and essential for communication, coordination, and cognition—also exhibited clear structural deterioration in treated animals.
These pathological changes resemble white matter injury sometimes observed in patients receiving intensive chemotherapy, which has been associated with cognitive impairment commonly referred to as “chemo brain.” Clinical manifestations of myelin damage may include numbness, pain, impaired movement, and difficulties with memory and concentration.
Cells Regress Instead of Dying
To investigate the underlying cellular mechanisms, the researchers examined oligodendrocytes, the specialized cells responsible for producing and maintaining myelin in the central nervous system. Rather than undergoing cell death, these oligodendrocytes appeared to regress into a more primitive, immature state following D+Q treatment.
Further analyses suggested that the drug combination disrupted cellular metabolism, likely depriving oligodendrocytes of the energy required to maintain complex myelin structures. As a result, the cells simplified both their structure and function, resembling immature precursor cells and producing substantially less protective myelin.
Interestingly, these altered cells closely resembled a distinct population of oligodendrocytes previously identified in brain tissue from patients with multiple sclerosis. This observation suggests that stressed but still viable myelin-producing cells may play a more important role in multiple sclerosis than previously recognized.
Implications for Multiple Sclerosis and Aging
If oligodendrocytes in multiple sclerosis and other demyelinating diseases commonly regress rather than die, it may be possible to restore them to a fully functional state. The University of Connecticut team is currently investigating whether these damaged cells can recover and resume normal myelin production once the underlying cellular stress has been eliminated.
Such findings could open new therapeutic strategies focused on restoring existing oligodendrocytes instead of replacing them. At the same time, the results underscore that interventions designed to eliminate aged or damaged cells, such as senolytic therapies, may produce unintended consequences for highly specialized brain tissue.
Experts say the findings highlight the need for more rigorous studies specifically evaluating the neurological safety of anti-aging drugs before they become widely adopted. Until more comprehensive safety data are available, the researchers advise caution regarding self-experimentation with senolytic combinations such as D+Q, particularly among younger individuals, who may be more susceptible to adverse neurological effects.
