A research is suggesting that aging and wisdom go hand-in-hand. There is a particular molecule linked with learning, memory and aging.
The well-known anti-aging protein SIRT1 appears to have several roles. It does both reduce the aging effect as well as helping learning and memory to be enhanced. This study was published online in Nature the 11th of July.
SIRT1 is a protein from the family of Sirtuins. It supports the body to control its metabolism and gene activity related to biological processes associated with aging. In this study, Li Huei Tsai who is a neuroscientist and Howard Hughes Medical Institute Investigator at MIT, has shown that SIRT1 does also have an important contribution in assuring strong memory and learning activities, at least for the case of mice (study was conducted on mice).
The team did consider that SIRT1 had a significant role in facilitating brain activities, equally as resveratrol, which is an activator of sirtuins. For mouse, SIRT1 assured the survival of neurons that prevents Alzheimer’s disease to develop. Moreover, resveratrol did also significantly enhance the mice’s capacity to remember and learn. Earlier studies have also shown that resveratrol influence all the seven sirtuins present in various mammals. However, these recent studies had no clue what biological processes SIRT1 did influence.
Tsai and her team created genetically engineered mice, which had a low amount of SIRT1 present in their brains. Several memory and learning test was then conducted. It was found that the mice had difficulties in memorizing the precise position of objects in a submerged platform in a water maze. They were even unable to demarcate new and old objects were placed in the cage. In other words, they scored low in the memory test. Tsai said that limiting SIRT1 in these animals does definitely impair their learning abilities.
As the team investigated further into the brains of the mice having a low level of SIRT1, it was found that these mice had fewer links between neurons (links known as synapses). The lack of synapses triggered the disability of lacking long-term memory. The discovery helped in understating various molecules associated with memory. These mice with limited SIRT1 had also less of the protein known as CREB, which is present in their brains. This is a protein (CREB) which enforces the links between neurons.
As the team investigated further they found that SIRT1 controlled CREB levels via something known as RNA or rather microRNA-134 or miR-134. SIRT1 does usually team up with protein known as YY1 to reduce the generation of miR-134. However, with a limited amount of SIRT1, ultimately a higher volume of miR-124 was produced. The production of microRNA did thereafter influence RNA to diminish or even stop the production of CREB protein.
Valter Longo from the University of Southern California in Los Angeles says that this study confirms that SIRT1 is a master protein responsible for the regulation of cell function and metabolism. Currently, Longo is involved in a related study on SIRT1 and his findings on memory and learning will be published in the Journal of Neuroscience in 21st of July.
However, he mentioned that increasing the level of SIRT1 activity did not necessarily improve memory for mice. He also cautioned that the long-term effect of having a high level of SIRT1 is still uncertain. In a previous research published by Longo, he concluded that increasing the level of SIRT1 activity had negative effects on neurons.
Paolo Sassone-Corsi who is a molecular biologist at the University of California, Irvine says that Tsai’s study has demonstrated a new pathway. Paolo said that “Now you can see a new piece of the horizon that wasn’t there before. It’s really exciting.” It can also significantly help in other studies on memory and learning.
Source: Science News
Sat, Jul 17, 2010
Anti Aging