Hyaluronic acid nanospheres loaded with taurine captured hundreds of inflammatory proteins from the blood of aged mice after surgery and restored their spatial memory
Hyaluronic acid nanospheres loaded with taurine captured hundreds of inflammatory proteins from the blood of aged mice after surgery and restored their spatial memory
A team from Duke University and the University of California, Los Angeles described in a preprint dated 18 September 2026 a nanosphere called HA-Tau, made of hyaluronic acid conjugated with taurine. In aged mice after bone surgery, a single injection of the nanospheres reduced inflammatory proteins in the blood, preserved the blood-brain barrier, and restored spatial memory. The same nanospheres produced a comparable effect on plasma and brain vascular cells from elderly human donors.
Bone surgery is a trauma that does not directly injure the brain, yet it releases a surge of cytokines, signaling proteins of inflammation, into the bloodstream. The blood-brain barrier, the wall separating the blood from the brain, holds these molecules back less effectively with age. Cytokines leak through and activate glia, the resident support cells of the brain: after hip or knee surgery an elderly patient sometimes wakes in a state of confusion, with memory lapses lasting days. Corticosteroids and antibodies targeting a single cytokine offer limited help because the network is redundant, and blocking one signal causes neighboring pathways to compensate.
The team, led by Shyni Varghese, set out to physically scavenge inflammatory signals directly from the blood. They conjugated taurine, an amino acid with antioxidant activity, to hyaluronic acid, a natural connective-tissue polymer, and assembled the conjugate into nanospheres roughly 200 nanometers in diameter.
Molecular docking, a computational method that models how molecules fit together, showed that partial substitution with taurine opens new binding sites for cytokines and strengthens the existing ones, while full substitution abolishes both effects because the extra groups sterically block the protein from docking. The working degree of substitution, roughly 43%, was chosen not by calculation alone but by direct testing against blood proteins, where it outperformed all other variants.
Taurine carries a controversial reputation in geroscience: a 2023 Science paper linked declining blood taurine levels to aging and reported that taurine supplementation extended lifespan in mice, but later work failed to confirm the association in humans. In the nanosphere, taurine plays a more modest part, serving as a hook that grabs cytokines.
The nanospheres were injected into 20–22-month-old mice, an age equivalent to elderly in humans, thirty minutes after tibial fracture. A single injection captured roughly 548 distinct proteins from plasma, most of them belonging to inflammatory pathways. In nanosphere-treated mice, circulating IL-6, IL-1β, and TNF-α dropped, barrier-associated tight-junction proteins were preserved, dye leakage across the barrier decreased, glial activation in the hippocampus (the brain's memory center) fell to near-normal levels, and performance in a spatial memory test matched that of unoperated controls.
A year earlier, the same laboratory showed that the senolytics dasatinib and quercetin, which kill senescent cells, also reduce neuroinflammation after surgery. That approach eliminated the messenger; the new one intercepts the message while leaving the cells untouched.
"HA-Tau nanospheres act as a molecular decoy: they quench excessive inflammation without shutting down the immune system entirely," the authors write.
Translation to humans was tested on plasma from elderly donors and on human brain vascular cells. The captured proteins again converged on a single node: IL-6, IL-1β, and TNF-α, the cytokines that drive inflammation through the NF-κB switch. The barrier was less permeable in the presence of nanospheres than without them. The same cytokine node has already been linked by Canadian data to cognitive impairment in living humans.
The nanospheres themselves barely enter the brain and accumulate mainly in the liver, causing no detectable damage there within the first 24 hours. The brain is thus protected by a substance that never even crosses the blood-brain barrier: the interception of inflammatory signals takes place entirely in the bloodstream.