Research using human brain organoids onboard the International Space Station is revealing biological changes linked to neurological disease and helping scientists test potential therapies. Studies highlighted in Upward include work on Rett syndrome, Parkinson’s disease, multiple sclerosis, and Alzheimer’s disease, including research that helped lead to a Rett syndrome clinical trial.

USC researchers found that exposure to common outdoor air pollutants may be linked to changes in brain regions especially vulnerable to Alzheimer’s disease. The study analyzed brain scans and residential pollution estimates from 1,484 adults without dementia or a history of stroke.

Among older women, higher exposure to fine particulate matter (PM2.5) and nitrogen dioxide (NO2) was associated with a thinner cortex in memory-related brain regions commonly affected by Alzheimer’s disease. A separate group of younger men showed a different pattern, with greater pollution exposure associated with a thicker cortex in the same regions. That association weakened with age and reversed around age 65.

The findings suggest the brain’s response to air pollution may change across the aging process. Because the groups differed in age and sex, and participants were assessed at one point in time, the study cannot determine whether pollution caused the observed differences or explain why the patterns varied. Longer-term studies are needed to examine whether these brain changes are linked to inflammation, Alzheimer’s-related biomarkers and future dementia risk.

Hyeonwook Chae and colleagues have developed wearable, transparent organic light-emitting diode (OLED) glasses that can be used to deliver light pulses to the wearer’s eyes for gamma wave entrainment. Gamma wave entrainment uses flickering light to synchronize brainwave rhythms to a high-frequency gamma oscillation, which is associated with communication between brain regions. Some researchers are studying gamma wave entrainment for its potential to improve memory and focus in the early stages of Alzheimer’s disease. But finding a way to deliver the necessary light stimulation in a comfortable fashion has made it difficult to study the treatment’s full potential. To address this, Chae et al. developed transparent OLED glasses capable of delivering flickering light stimulation at the level needed for gamma entrainment, while still being transparent enough to see through under ambient light conditions. Volunteers wearing the glasses did experience gamma entrainment that enhanced connectivity between the occipital and frontal regions of the brain. This enhanced connectivity appeared to be stronger with transparent versus non-transparent OLEDs. Wearers also reported less eye strain and “dazzling” with the transparent glasses, suggesting they would be more appropriate for everyday use.

Mount Sinai researchers find that TIMP2 supports microglial function and reduces age-related cellular changes linked to inflammation in mice

Blood tests measuring plasma p-tau217 offer a promising, non-invasive alternative for Alzheimer's disease diagnosis. In a multicenter head-to-head evaluation, researchers compared nine commercial p-tau217 assays. While seven assays demonstrated high diagnostic accuracy for detecting amyloid pathology, two showed substantially lower performance. The findings emphasize that these tests are not interchangeable and require tailored calibration for clinical use.

Established Alzheimer’s markers are also detected in blood samples from Nigeria and Tanzania. But other proteins in the blood differ from those seen in a comparable group in Canada. This is important if blood tests for Alzheimer’s are to be used globally.