Aggregated forms of amyloid-β peptide (Aβ) and tau are major components of senile plaques and neurofibrillary tangles, respectively, which are pathological hallmarks in the brains of Alzheimer disease (AD) patients. Several lines of evidence suggest that accumulation of Aβ induces the tau-mediated neuronal toxicity and symptomatic manifestations of AD. Thus, facilitation of the clearance of aggregated Aβ and tau has been highlighted as a plausible therapeutic for AD. In addition, genetic studies in AD implicate the pathological roles of glial cells, such as astrocytes and microglia. We recently identified kallikrein-related peptidase 7 (KLK7) as a novel aggregated Aβ-degrading enzyme secreted from astrocyte, suggesting that astrocyte is a cellular target in AD therapeutics. Moreover, we have developed a novel small compound called photooxygenation catalyst that facilitates the selective degradation of aggregated proteins in vivo. I will discuss with these novel approaches for anti-aggregated proteins against AD.