MCU knockdown in hippocampal neurons improves memory performance of an Alzheimer's disease mouse model

Acta Biochim Biophys Sin (Shanghai). 2022 Oct 25;54(10):1528-1539. doi: 10.3724/abbs.2022138.

Abstract

Alzheimer's disease (AD) is a progressive and degenerative disorder accompanied by cognitive decline, which could be promoted by mitochondrial dysfunction induced by mitochondrial Ca 2+ (mCa 2+) homeostasis Mitochondrial calcium uniporter (MCU), a key channel of mCa 2+ uptake, may be a target for AD treatment. In the present study, we reveal for the first time that MCU knockdown in hippocampal neurons improves the memory performance of APP/PS1/tau mice through radial arm maze task. Western blot analysis, transmission electron microscopy (TEM), Golgi staining, immunohistochemistry (IHC) and ELISA results demonstrate that MCU knockdown in hippocampal neurons upregulates the levels of postsynaptic density protein 95 (PSD95) and synaptophysin (SYP), and increases the numbers of synapses and dendritic spines. Meanwhile, MCU knockdown in hippocampal neurons decreases the neuroinflammatory response induced by astrogliosis and high levels of IL-1β and TNF-α, and improves the PINK1-Parkin mitophagy signaling pathway and increases the level of Beclin-1 but decreases the level of P62. In addition, MCU knockdown in hippocampal neurons recovers the average volume and number of mitochondria. These data confirm that MCU knockdown in hippocampal neurons improves the memory performance of APP/PS1/tau mice through ameliorating the synapse structure and function, relieving the inflammation response and recovering mitophagy, indicating that MCU inhibition has the potential to be developed as a novel therapy for AD.

Keywords: Alzheimer’s disease; memory behavior deficit; mitochondrial calcium uniporter; mitophagy; neuroinflammation response.

MeSH terms

  • Alzheimer Disease* / metabolism
  • Animals
  • Calcium Channels* / genetics
  • Disease Models, Animal
  • Hippocampus / metabolism
  • Memory*
  • Mice
  • Mice, Transgenic
  • Neurons* / metabolism

Substances

  • mitochondrial calcium uniporter
  • Calcium Channels

Grants and funding

This work was supported by the grants from the National Natural Science Foundation of China (Nos. 31600865, 82171428, and 82271484), the Four “Batches” Innovation Project of Invigorating Medical through Science and Technology of Shanxi Province (No. 2021XM33), the Open Fund from Key Laboratory of Cellular Physiology (Shanxi Medical University), the Ministry of Education, China (No. KLMEC/SXMU-202013), the Shanxi “1331 Project” Key Subjects Construction (No. 1331KSC), and the Research Project supported by Shanxi Scholarship Council of China (Nos. 2020-083, and 2022-115).