The fruit fly is one of the most well-understood model organisms, making them ideal for biological and genetic research. This tiny insect recently made headlines once again, as researchers were able to reverse symptoms of Alzheimer’s after they adjusted the production of key enzymes.
Analyzing Enzyme Manipulation In Fruit Flies
Researchers from Drexel University recently published their study in The Journal of Neuroscience. They were interested in enzyme manipulation in regards to gene expression and in turn, the symptoms of Alzheimer’s.
Previously, it had been discovered that an enzyme known as HDAC2 is necessary for neural development. Researchers also found that when this enzyme is present in uneven amounts, this could affect gene expression. This is what is known as epigenetics — or the study of changes in organisms caused by modification of gene expression.
Since epigenetic changes may influence some of the cognitive symptoms expressed in Alzheimer’s, this was an area of particular interest. This led to the discovery of a specific enzyme, known as Tip60 HAT – which is able to counteract the effects of HDAC2 on symptoms of Alzheimer’s.
HDAC2 and Its Effect on Alzheimer’s Symptoms
It is believed that early in the progression of Alzheimer’s, issues with learning and memory are linked to elevated levels of HDAC2. This enzyme helps to control the way in which genes linked to memory and learning are expressed. When HDAC2 overwhelms Tip60 HAT (the enzyme it is paired with), it may cause a regression in genes.
If this is the case, issues with neuroplasticity may arise. This would affect the brain’s ability to adapt to new stimuli and react to previously encountered stimuli. However, once the researchers added extra Tip60 HAT in the brain of fruit flies showcasing Alzheimer’s symptoms, the balance between these two enzymes was fully restored.
Once balance was restored, it was found that the behaviors the researchers initially taught the flies were relearned and remembered. This study was unique in that the team looked at how Alzheimer’s affected flies in early development. In comparison, most studies focus on human post-mortem samples, which ignores what is happening during the early progression of neurodegeneration.
Moreover, the researchers identified a group of genes related to repressed brain function due to elevated levels of HDAC2. Once increased levels of Tip60 HAT were introduced, 9 out of 11 genes tested were restored. This is encouraging, as this may lead to non-invasive ways to prevent the disruption of genes early on.
Epigenetic Alterations in Alzheimer’s Disease
The term “epigenetics” was first introduced in the early 1940s. This concept was later defined as the science of heritable traits which result in chromosomal changes without altering the DNA sequence. In more recent years, this area of research has become of particular interest among neuroscientists.
Often referred to as “epigenetic newcomers,” neuroscientists are beginning to uncover the importance of epigenetics with regards to the nervous system. Although more research is needed, lifestyle changes which increase Alzheimer’s risk may be caused by epigenetic changes.
In addition, scientists from the University of Pennsylvania mapped out the epigenomic landscape of Alzheimer’s brains. After comparing them to healthy brains from both young and elderly donors, a potential epigenetic link was discovered. Once again, their findings were based on an imbalance.
This time, the core focus was on the link between the development of Alzheimer’s and an epigenetic mechanism known as H4K16ac (acetylation of lysine 16 on histone H4). As the brain ages normally, the amount of H4K16ac increases. This helps to better control possible DNA damage and help maintain healthy neurological function.
In comparison, the patients with Alzheimer’s displayed a loss of H4K16ac in the genes that were linked to both aging and Alzheimer’s. These findings were published in Nature Neuroscience.
Are You At Risk?
Scientists are not fully aware of what causes Alzheimer’s. However, some of the greatest risk factors outside of age include a family history (especially in terms of risk genes), poor lifestyle habits, traumatic brain injury, and poor cardiovascular health.
In order to better understand your current level of cognitive functioning, BrainTest® can help. This app will allow you to better detect early warning signs of Alzheimer’s, dementia, and other cognitive impairments.