Study Reveals Menin Protein's Crucial Role in Hypothalamus Aging and Cognitive Decline

On March 16, 2023, researchers published a significant study in the scientific journal PLOS Biology that examines the critical role of the Menin protein in mouse brains. Led by Lige Leng and colleagues, the research investigates how Menin influences hypothalamus aging and cognitive decline. The findings shed light on the complex biological mechanisms that connect genetic, inflammatory, and metabolic factors during the aging process.

According to the study, Menin levels were observed to fall with age specifically in certain neurons within the ventromedial hypothalamus (VMH) of mice. Commenting on these findings, Lige Leng stated, "We speculate that the decline of Menin expression in the hypothalamus with age may be one of the driving factors of aging, and Menin may be the key protein connecting the genetic, inflammatory, and metabolic factors of aging. D-serine is a potentially promising therapeutic for cognitive decline."

Furthermore, the research demonstrated the direct consequences of altering Menin levels in laboratory animals. Reducing Menin in younger mice actively increased hypothalamic inflammation and successfully brought on various aging-related traits. These traits included lower bone mass, thinner skin, notable cognitive decline, and a shorter overall lifespan, illustrating the protein's vital systemic functions.

To confirm these pathways, the scientific team conducted restorative experiments on older subjects. Delivering the gene for Menin directly into the hypothalamus of elderly mice visibly improved skin thickness, bone mass, cognition, learning, and balance, while also successfully extending their lifespan. Lige Leng explained the mechanism, noting that "Ventromedial hypothalamus (VMH) Menin signaling diminished in aged mice, which contributes to systemic aging phenotypes and cognitive deficits. The effects of Menin on aging are mediated by neuroinflammatory changes and metabolic pathway signaling, accompanied by serine deficiency in VMH, while restoration of Menin in VMH reversed aging-related phenotypes."

Additionally, the study explored targeted treatments involving metabolic derivatives linked to the pathway. Giving mice D-serine in their drinking water for a period of three weeks improved their overall cognitive performance. However, this specific treatment did not reproduce the broader physical aging trait improvements that were observed when the Menin gene itself was delivered to the hypothalamus.