Back

7-ketocholesterol contributes to microglia-driven increases in astrocyte reactive oxygen species in Alzheimer's disease

Radhakrishnan, K.; Zhang, Y.; Mustapha, O.; Weigel, T. K.; Upchurch, C.; Tian, X.; Herbert, F.; Huang, W.; Leitinger, N.; Eyo, U. B.; Ai, H.; Ferris, H. A.

2025-01-19 neuroscience
10.1101/2025.01.19.633810 bioRxiv
Show abstract

Oxidative stress is a prominent feature of Alzheimers disease. Within this context, cholesterol undergoes oxidation, producing the pro-inflammatory product 7-ketocholesterol (7-KC). In this study, we observe elevated levels of 7-KC in the brains of the 3xTg mouse model of AD. To further understand the contribution of 7-KC on the oxidative environment, we developed a method to express a genetically encoded fluorescent hydrogen peroxide (H2O2) sensor in astrocytes, the primary source of cholesterol in the brain. With this sensor, we discovered that 7-KC increases H2O2 levels in astrocytes in vivo, but not when directly applied to astrocytes in vitro. Interestingly, when 7-KC was applied to a microglia cell line alone or mixed astrocyte and microglia cultures, it resulted in microglia activation and increased oxidative stress in astrocytes. Depletion of microglia from 3xTg mice resulted in reduced 7-KC in the brains of these mice. Taken together, these findings suggest that 7-KC, acting through microglia, contributes to increased astrocyte oxidative stress in AD. This study sheds light on the complex interplay between cholesterol oxidation, microglia activation, and astrocyte oxidative stress in the pathogenesis of AD.

Matching journals

The top 7 journals account for 50% of the predicted probability mass.

50% of probability mass above

"Similar papers" are the closest papers from that journal in the model's embedding space. They show what the match is built on, but the ranking comes mostly from a classifier over the whole training set, not from these examples alone.