| Author |
Gannon M, Wang B, Stringfellow SA, Quintin S, Mendoza I, Srikantha T, Roberts AC, Saito T, Saido TC, Roberson ED, Yacoubian TA.
|
| Abstract |
Alzheimer's disease (AD) is characterized by progressive cognitive impairment associated with synaptic dysfunction and dendritic spine loss and the pathological hallmarks of amyloid beta (Aβ) plaques and hyperphosphorylated tau tangles. 14-3-3 proteins are a highly conserved family of proteins whose functions include regulation of protein folding, neuronal architecture, and synaptic function. Additionally, 14-3-3s interact with both Aβ and tau, and reduced levels of 14-3-3s have been shown in the brains of AD patients and in AD mouse models. Here we examine the neuroprotective potential of the 14-3-3θ isoform in AD models. We demonstrate that 14-3-3θ overexpression is protective and 14-3-3θ inhibition is detrimental against oligomeric Aβ-induced neuronal death in primary cortical cultures. Overexpression of 14-3-3θ using an adeno-associated viral vector failed to improve performance on behavioral tests, improve Aβ pathology, or affect synaptic density in the J20 AD mouse model. Similarly, crossing a second AD mouse model, the AppNL-G-F knock-in (APP KI) mouse, with 14-3-3θ transgenic mice failed to rescue behavioral deficits, reduce Aβ pathology, or impact synaptic density in the APP KI mouse model. 14-3-3θ is likely partially insolubilized in the APP models, as demonstrated by proteinase K digestion. These findings do not support increasing 14-3-3θ expression as a therapeutic approach for AD.Significance StatementDespite being the most common form of neurodegeneration, effective treatments for Alzheimer's disease (AD) remain elusive and therefore novel therapeutic targets are needed. 14-3-3 proteins, a highly conserved family of chaperone proteins involved in regulating synaptic function and neuronal architecture, are reduced in human AD patients, making them a promising novel target. In this study, we examined the effects of increasing the 14-3-3θ isoform in AD models. We observed that 14-3-3θ overexpression reduces oligomeric Aβ toxicity in cortical cultures. However, increasing the 14-3-3θ expression in two different AD mouse models failed to rescue behavioral or pathological phenotypes, indicating a more complicated relationship between 14-3-3s and AD.
|
