Hebrew University of Jerusalem’s Prof. Hermona Soreq, a leading researcher in the field of gene expression in the brain, has made a significant breakthrough in the study of Alzheimer’s disease. The research explains why women experience more severe and faster dementia than men. It has long been known that women with Alzheimer’s disease suffer from accelerated dementia and the loss of cholinergic neurons compared to males. However, until now, the causes of this discrepancy have remained unknown. In a recently published article titled “Sex-specific declines in cholinergic-targeting tRNA fragments in the nucleus” in the Alzheimer’s & Dementia journal, Soreq and her colleagues at the Edmond & Lily Safra Center for Brain Sciences discovered a molecular mechanism that takes place in the brain of female Alzheimer’s patients.

The team discovered that a family of tiny RNA fragments has a direct relationship with the rate of disease development in women. The researchers found that the reservoir of the brain’s fragments in the brain reflects a rapid development of cognitive impairment among women with Alzheimer’s, but it is not reflected in the brain structure of women. The study showed that the decline in the reservoir of RNA fragments in the brain leads to a speedup in the development of cognitive decline in females.

The study further revealed that the reservoirs of RNA fragments come from mitochondria, which are membrane-bound cell organelles that generate most of the chemical energy needed to power the cell’s biochemical reactions. Mitochondria are contributed by the mother. This discovery sheds new light on the control mechanisms for the development of Alzheimer’s among women and highlights the significant differences in the way dementia develops in women and the rapid decline in cognitive indicators.

Soreq believes that this discovery is an essential step towards finding a drug tailored to women who are ill. She explains that this is the first time they can provide a molecular explanation for the processes that happen in the brains of women and why the therapeutic protocol offered until now is not satisfactory. She hopes that it will lead to better medical care based on RNA-based treatments. With RNA-based treatments becoming practical after the COVID-19 pandemic, there is hope for better care for Alzheimer’s patients and their families worldwide.

By Impact Lab