Abstract
BACKGROUND: Neurogranin (Ng) is considered a biomarker for synaptic dysfunction in Alzheimer’s disease (AD). In contrast, the inflammasome complex has been shown to exacerbate AD pathology. METHOD: We investigated the protein expression, morphological differences of Ng and correlated Ng to hyperphosphorylated tau in the postmortem brains of 17 AD cases and 17 age and sex‐matched controls. In addition, we correlated the Ng expression with two different epitopes of apoptosis‐associated speck‐like protein containing a caspase recruitment domain (ASC). RESULT: We show a reduction of Ng immunopositive neurons and morphological differences in AD compared to controls. Ng immunostaining was negatively correlated with neurofibrillary tangles, humanized anti‐ASC (IC100) positive neurons and anti‐ ASC positive microglia, in AD. CONCLUSION: The finding of a negative correlation between Ng and ASC speck protein expression in postmortem brains of AD suggests that the activation of inflammasome/ASC speck pathway may play an important role in synaptic degeneration in AD.