Pune, July 5, 2012 (Thanks to Arun Subramanian, Southern Illinois University, Carbondale, USA for the news alert): "Many animals are characterized by declining brain function at advanced ages, including honeybees (Apis mellifera),"say the authors of a research article* in an online edition of the journal Experimental Gerontology dated May 21, 2012. "Variation in honeybee social development, moreover," the authors continue, "results in individual differences in the progression of aging that may be accelerated, delayed, and sometimes reversed by changes in behavior.
Worker honey bees in the colony organization, change their working behaviour as they age, the phenomenon being termed 'age polyethism'. Younger bees of Apis mellifera attend nursing duties during their first 10 days of age. Later they attend to duties within the hive, like comb building or repair, nectar processing and guarding. From the age of 21 days and on until they die, they go out of the colony and forage for pollen and nectar. Some of these perform scout duties to find out good sources of food or sites for nest building for swarms. It is well-known that the worker bees can respond to changes in colony conditions by accelerating, delaying, or even reversing their behavioural development. Ament et al.** showed that molecular pathways influence the age at which worker bees shift from working in the hive to food-gathering. Thus, regulation of division of labour involves nutritionally related genes. Baker, Wolschin and Amdam's recent research* shows that foraging bees have age-associated learning deficits, and the learning performance can be recovered when the foragers revert to nursing duties. "The research further shows that "the recovery-related brain plasticity is connected to cellular resilience, maintenance and repair processes." Following is the news release by the Arizona State University on this research.
* Baker, N., Wolschin, F. and Amdam, G.V. 2012. Age-related learning deficits can be reversible in honeybees Aois mellifera. Experimental Gerontology. Available online: May 21, 2012.
**Ament, S.A., Corona, M., Pollock, H.S. and Robinson, G.E. 2008. Insulin signaling is in the regulation of worker division of labor in honey bee colonies. Proceedings of the Naitonal Academy of Sciences105 (11); 4226-4231. Published online before print March 12, 2008. doi: 10.1073/pnas.0800630105
ARIZONA STATE UNIVERSITY - ASU News posted on July 2, 2012
Scientists discover bees can 'turn back time,' reversing brain aging
Scientists at Arizona State University have discovered that older honey bees effectively reverse brain aging when they take on nest responsibilities typically handled by much younger bees. While current research on human age-related dementia focuses on potential new drug treatments, researchers say these findings suggest that social interventions may be used to slow or treat age-related dementia.
In a study published in the scientific journal Experimental Gerontology, a team of scientists from ASU and the Norwegian University of Life Sciences, led by Gro Amdam, an associate professor in ASU's School of Life Sciences, presented findings that show that tricking older, foraging bees into doing social tasks inside the nest causes changes in the molecular structure of their brains.
"We know from previous research that when bees stay in the nest and take care of larvae -- the bee babies -- they remain mentally competent for as long as we observe them," said Amdam. "However, after a period of nursing, bees fly out gathering food and begin aging very quickly. After just two weeks, foraging bees have worn wings, hairless bodies, and more importantly, lose brain function -- basically measured as the ability to learn new things. We wanted to find out if there was plasticity in this aging pattern so we asked the question, 'What would happen if we asked the foraging bees to take care of larval babies again?"
During experiments, scientists removed all of the younger nurse bees from the nest -- leaving only the queen and babies. When the older, foraging bees returned to the nest, activity diminished for several days. Then, some of the old bees returned to searching for food, while others cared for the nest snd larvae. Researchers discovered that after 10 days, about 50 percent of the older bees caring for the nest and larvae had significantly improved their ability to learn new things.
Amdam's international team not only saw a recovery in the bees' ability to learn, they discovered a change in proteins in the bees' brains. When comparing the brains that improved relative to those that did not, two proteins noticeably changed. The found Prx6, a protein also found in humans that can help protect against dementia -- including diseases such as Alzheimer's -- and they discovered a second and documented "chaperone" protein that protects other proteins from being damaged when brain or other tissues are exposed to cell-level stress.
In general, researchers are interested in creating a drug that could help people maintain brain function, yet they may be facing up to 30 yeas of basic research and trials.
"Maybe social intervention -- changing how you deal with your surroundings -- is something we can do today to help our brains stay younger," said Amdam. "Since the proteins being researched in people are the same proteins bees have, these proteins may be able to spontaneously respond to specific social edxperiences."
Amdam suggests further studies are needed on mammals such as rats in order to investigate whether the same molecular changes that the bees experience might be socially inducible in people.