DLG4 and Alzheimer disease: Yang et al. [94] demonstrated that the stereotaxic injection of phloroglucinol, the phlorotannins’ building block, attenuated cognitive function impairments in the 5XFAD mouse model of AD by regulating synaptic plasticity, with the reduction in dendritic spine density and the levels of synaptic proteins ((synaptophysin and post synaptic density protein 95 (PSD-95)) [94].