New Study Suggests Metformin May Slow Brain Aging in Monkeys, Paving Way for Human Trials

Metformin, primarily known as a first-line treatment for type 2 diabetes, is under investigation for its potential in slowing brain aging, according to a recent study involving crab-eating macaques. Conducted by biologist Yuanhan Yang and his team from the Chinese Academy of Sciences, this research explores the anti-aging effects of metformin on primates, marking a significant step beyond previous studies on other species and humans.

The Study's Design and Results

The 40-month study observed a group of 13-16 year old male crab-eating macaques, akin to human development stages of 40-50 years. A subset of these macaques received daily metformin doses for over three years, resembling standard treatment procedures for type 2 diabetes in humans. Control groups of younger and middle-aged macaques were also monitored to account for natural aging effects.

The findings suggest that metformin holds potential in slowing brain aging, possibly offering treatments for neurodegenerative and chronic conditions. The researchers assessed various aspects of aging, including physiology, memory, learning, cognitive flexibility, and brain morphology. Moreover, they employed advanced techniques like pan-tissue transcriptomics, DNA methylomics, plasma proteomics, and metabolomics to evaluate metformin's effects on aging.

The study revealed that metformin reduced fluctuations in gene transcription associated with aging across different tissues, impacting pathways linked to aging, such as cell death and fibrosis. It also reactivated aging-repressed pathways involved in development, including DNA repair and lipid metabolism. Furthermore, metformin decreased the biological age of the older monkeys, mitigated liver aging, and enhanced the production of liver-protecting chemicals.

Impact on Brain Aging and Neuroprotection

Significantly, the study demonstrated that metformin delayed brain aging and provided neuroprotection in elderly macaques, effectively rejuvenating their frontal lobe by nearly six years. However, the researchers acknowledged the limited sample size and the absence of female monkeys in the study as points of caution.

A Step towards Human Trials

While the study's authors highlighted the implications of metformin in delaying aging processes and its potential to mitigate aging-related health issues, they also emphasized that the full extent of its effects and mechanisms in primates remain to be fully understood. Notably, this research represents a crucial advancement in the field, steering the course towards human trials.

Future of Metformin in Aging Research

The team's findings have garnered interest beyond the realm of animal research. Members of the Chinese research team are already engaged in a 120-person phase II clinical trial, in partnership with a pharmaceutical company manufacturing metformin, to explore similar effects in humans. This progression signifies a pivotal step toward determining metformin's viability as a therapeutic agent in the context of aging.

The study's results are published in the journal Cell. As research in this domain continues to evolve, the potential of metformin in addressing the challenges of aging and its associated health issues remains a burgeoning area of exploration.