Department of Physiology and Developmental Biology, Brigham Young University, Provo, Utah, USA.
Department of Biology, Brigham Young University, Provo, Utah, USA.
Alzheimers Dement. 2021 Sep;17(9):1474-1486. doi: 10.1002/alz.12310. Epub 2021 Mar 2.
Sporadic Alzheimer's disease (AD) is strongly correlated with impaired brain glucose metabolism, which may affect AD onset and progression. Ketolysis has been suggested as an alternative pathway to fuel the brain.
RNA-seq profiles of post mortem AD brains were used to determine whether dysfunctional AD brain metabolism can be determined by impairments in glycolytic and ketolytic gene expression. Data were obtained from the Knight Alzheimer's Disease Research Center (62 cases; 13 controls), Mount Sinai Brain Bank (110 cases; 44 controls), and the Mayo Clinic Brain Bank (80 cases; 76 controls), and were normalized to cell type: astrocytes, microglia, neurons, oligodendrocytes.
In oligodendrocytes, both glycolytic and ketolytic pathways were significantly impaired in AD brains. Ketolytic gene expression was not significantly altered in neurons, astrocytes, and microglia.
Oligodendrocytes may contribute to brain hypometabolism observed in AD. These results are suggestive of a potential link between hypometabolism and dysmyelination in disease physiology. Additionally, ketones may be therapeutic in AD due to their ability to fuel neurons despite impaired glycolytic metabolism.
散发性阿尔茨海默病(AD)与脑葡萄糖代谢受损密切相关,这可能会影响 AD 的发病和进展。酮体分解已被认为是为大脑供能的替代途径。
使用死后 AD 大脑的 RNA-seq 图谱来确定糖酵解和酮体分解基因表达的损伤是否可以确定功能失调的 AD 大脑代谢。数据来自 Knight 阿尔茨海默病研究中心(62 例;13 例对照)、西奈山脑库(110 例;44 例对照)和梅奥诊所脑库(80 例;76 例对照),并按细胞类型归一化:星形胶质细胞、小胶质细胞、神经元、少突胶质细胞。
在少突胶质细胞中,AD 大脑中的糖酵解和酮体分解途径均明显受损。神经元、星形胶质细胞和小胶质细胞中酮体分解基因表达无明显改变。
少突胶质细胞可能导致 AD 中观察到的脑代谢低下。这些结果提示代谢低下与疾病生理中的脱髓鞘之间可能存在潜在联系。此外,由于酮体能够在糖酵解代谢受损的情况下为神经元供能,因此在 AD 中可能具有治疗作用。