Summary: Research indicates a strong correlation between a high-sugar diet, often linked to obesity, and the onset of insulin resistance in the brain, raising the risk of neurodegenerative conditions like Alzheimer’s.
This study has uncovered that the aforementioned insulin resistance impedes the capacity of glial cells to effectively remove neuronal debris, a critical process necessary to prevent neurodegeneration.
A team of researchers has discovered through their experiment with fruit flies, which share similarities with humans, that a diet high in sugar significantly reduces the levels of the PI3k protein in glial cells and the Draper protein in ensheathing glia, thereby hindering their debris-clearing function.
Key Facts:
- A high-sugar diet commonly associated with obesity can trigger insulin resistance in the brain, resulting in a decreased capacity for neuronal debris removal.
- Additionally, the research unveiled that the insulin resistance brought about by this diet decreases PI3k and Draper protein levels in glial cells, directly affecting their ability to eliminate debris.
- These findings link diet-induced insulin resistance to an elevation in the risk of neurodegenerative diseases, offering valuable insights for preventive therapies.
Source: PLOS
Researchers led by Mroj Alassaf at the Fred Hutchinson Cancer Research Center in the United States have uncovered a significant correlation between obesity and neurodegenerative diseases such as Alzheimer’s.
Utilizing the model of the common fruit fly, the study demonstrates that a high-sugar diet, a characteristic of obesity, causes insulin resistance in the brain, reducing the efficiency of removing neuronal debris and subsequently amplifying the risk of neurodegeneration.
Set to be published on November 7th in the open access journal PLOS Biology, this revelation is expected to influence the development of therapies aimed at reducing the risk of neurodegenerative diseases.
Although it is widely recognized that obesity is a risk factor for neurodegenerative disorders like Alzheimer’s and Parkinson’s, the exact nature of the relationship has remained shrouded in mystery. This new research endeavors to address the question by leveraging the similarities between humans and fruit flies.
Initial findings displaying that a high-sugar diet instates insulin resistance in the peripheral organs of flies led the research team to shift focus to the brain. In their assessment, they examined the glial cells, given that dysfunctional microglia are known to precipitate neural degeneration.
The research has unveiled that PI3k protein levels in glial cells decrease as a result of the high-sugar diet, denoting insulin resistance. They also delved into the equivalent of microglia in flies, known as ensheathing glia, which are chiefly responsible for the removal of neural debris, including degenerating axons. It was observed that these glia displayed low levels of the Draper protein, indicating impaired function.
Subsequent testing revealed that artificially reducing PI3k levels led to both insulin resistance and low Draper levels in ensheathing glia. Furthermore, it was demonstrated that subsequent to olfactory neuron damage, the ensheathing glia failed to eliminate the degenerating axons in flies fed a high sugar diet, as their Draper levels did not increase.
The authors further add, “By studying fruit flies, the authors establish that high-sugar diets trigger insulin resistance in glia, disrupting their ability to clear neuronal debris. This study provides insight into how obesity-inducing diets potentially contribute to the increased risk of neurodegenerative disorders.”
About this diet, obesity, and neurodegeneration research news
Author: Claire Turner
Source: PLOS
Contact: Claire Turner – PLOS
Image: The image is credited to Neuroscience News
Original Research: Open access.
“Diet-induced glial insulin resistance impairs the clearance of neuronal debris in Drosophila brain” by Akhila Rajan et al. PLOS Biology
Abstract
Diet-induced glial insulin resistance impairs the clearance of neuronal debris in Drosophila brain
Obesity significantly increases the risk of developing neurodegenerative disorders, yet the precise mechanisms underlying this connection remain unclear. Defects in glial phagocytic function are a key feature of neurodegenerative disorders, as delayed clearance of neuronal debris can result in inflammation, neuronal death, and poor nervous system recovery.
