LA JOLLA, June 5 — A research team at Scripps Research has identified a specific biochemical alteration that drives chronic inflammation in the brains of Alzheimer’s disease patients, a finding that may guide the development of more targeted therapies. The study centers on the STING protein, a cellular sensor that normally alerts the immune system to infections. In the context of Alzheimer’s, STING undergoes a chemical modification that converts it into a hyperactive state, causing it to continuously release inflammatory signals. Investigators discovered that the protein aggregates characteristic of Alzheimer’s—amyloid‑beta and alpha‑synuclein—can provoke this modification of STING.
Once altered, STING fuels a self‑sustaining cycle of inflammation that erodes synaptic connections between neurons, a process closely associated with the cognitive decline observed in the disease. The researchers also noted that external and internal stressors such as aging, air‑pollution exposure, and wildfire smoke may exacerbate the cycle by increasing nitric oxide levels in the brain.
Led by neurologist Stuart Lipton, the team conducted experiments in mice to test whether blocking the STING modification could mitigate neuroinflammation. By preventing the alteration at a single amino‑acid site—cysteine 148—the scientists observed a marked reduction in inflammatory markers and preservation of synaptic structures. This intervention did not impair the protein’s normal immune‑defense functions, distinguishing it from broad‑spectrum anti‑inflammatory drugs that suppress the entire immune response.
“Targeting the specific cysteine‑148 modification allows us to quiet the harmful overactivation of STING while leaving its protective role intact,” the researchers explained. This precision approach could represent a shift away from the many amyloid‑centric clinical trials that have yielded limited success, offering a new therapeutic avenue focused on neuroinflammation.
The Scripps team is now pursuing the design of small‑molecule inhibitors that can selectively block the detrimental modification of STING. Although the work remains in the preclinical stage, the results suggest that such compounds might eventually curb the inflammatory cascade that damages neuronal networks in Alzheimer’s disease. While further testing in humans is required, the discovery adds a crucial piece to the puzzle of Alzheimer’s pathology and renews optimism for strategies that address the disease’s inflammatory component.
Patients and caregivers are encouraged to stay informed about emerging research and consult healthcare professionals for personalized medical advice.
