Ultrasmall iron-gallic acid coordination polymer nanoparticles for scavenging ROS and suppressing inflammation in tauopathy-induced Alzheimer’s disease

Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder globally, with no effective treatment available yet. A crucial pathological hallmark of AD is the accumulation of hyperphosphorylated tau protein, which is deteriorated by reactive oxygen species (ROS) and neuroinflammation in AD progression. Thus, alleviation of ROS and inflammation has become a potential therapeutic strategy in many studies. Herein, we reported ultrasmall coordination polymer nanoparticles formed by ferric ions and gallic acid (Fe-GA CPNs), which owned antioxidant and anti-inflammation properties for AD therapeutics. The facilely prepared Fe-GA CPNs exhibited remarkable superoxide dismutase, peroxidase enzyme activity, and ROS eliminating ability with great water solubility, compared with gallic acid. We demonstrated that Fe-GA CPNs effectively relieved oxidative stress, ameliorated inflammation by downregulating TLR4/NF-κB and modulating microglial polarization towards anti-inflammation phenotype, and reduced hyperphosphorylated tau protein levels. Furthermore, Fe-GA CPNs treatment significantly improved cognitive function in tauopathy-induced AD rats, and achieved a neuroprotective effect against AD pathology. This study highlights the potential of coordination polymer nanoparticles as promising therapeutic candidates for AD and other tau-related neurodegenerative diseases.