第1个回答 2024-05-15
- As you age, your brain undergoes functional decline. You might forget where you placed your glasses or struggle to master a new skill. With the global aging population, one of the key challenges is to develop strategies for maintaining brain function. A recent study from researchers at University College Cork in Ireland offers hope by showing that some aspects of brain function decline can be reversed with the help of the gut microbiome. In their research, published in the journal NatureAging on August 9, 2021, the authors describe how the gut microbiome from young mice was transferred to older mice, reversing certain signs of aging in the brain. This groundbreaking study opens up a potential new treatment avenue based on gut microbiome interventions to slow brain aging and related cognitive issues.
- The study, led by Professor John F. Cryan, Deputy Director for Research and Innovation at University College Cork, found that after the fecal transplants, the gut microbiomes of the older mice began to resemble those of the younger mice. For instance, the common gut bacterium Enterococcus became more abundant in the older mice, similar to that in the younger mice. Changes were also observed in the brain, particularly in the hippocampus, a region of the brain associated with learning and memory. The hippocampi of the older mice started to physically and chemically resemble those of the younger mice. The mice that received the fecal transplants from young mice also learned to solve mazes faster and retained the layout better in subsequent attempts compared to those receiving fecal transplants from older mice.
- Cryan comments, "It's almost as if we can press a reverse button on the aging process." However, while the gut microbiome transplantation could reverse multiple aspects of brain and immune function in the older mice, not all changes were reversed. For example, the social interaction levels did not significantly change, which was surprising as the gut microbiome has been shown to affect social interaction in other studies. Some scientists, such as Arya Biragyn from the National Institute on Aging, have raised questions about the study, calling for more experiments to confirm the actual changes in the gut microbiome. Biragyn is uncertain whether the new microbes truly colonized the recipient animals' guts or simply passed through. Sean Gibbons, a researcher in gut microbiome at the Institute for Systems Biology, also points out that the field of fecal transplantation in mice is complex. He notes that while some studies have found beneficial effects, such as increased neurogenesis in the hippocampus and growth in the gut of young germ-free mice, at least one study found that transplanting feces from old rats into young rats increased levels of pro-inflammatory cytokines and oxidative stress, leading to cognitive impairment.
- Cryan concludes, "We and other research teams have previously found the gut microbiome to play a key role in aging and the aging process. This new research is expected to spark a transformative shift in the field, as we are certain that the gut microbiome can be harnessed to reverse brain aging. We've also seen evidence of improved learning abilities and cognitive function. Although this is very exciting progress, it is still in the early stages, and more research is needed to understand how these findings can be translated to humans." This new research further underscores the importance of the gut microbiome in many aspects of health, particularly on the brain-gut axis, where brain function can be positively influenced. It opens up possibilities for regulating the gut microbiome as a therapeutic target for influencing brain health. Given that the study is based entirely on rodents, Cryan exercises caution in prematurely extending the research to humans. Nevertheless, he believes the study offers hope: "The advantage of your gut microbiome over your genome is that you can change it."