Although it has been discovered that obesity plays a role in the
onset of type 2 diabetes, scientists aren't certain how the excess
weight triggers the disease.
What scientists do know is that obesity causes stress in the endoplasmic
reticulum (ER), a system of cell membranes found inside cells. This
stress results in the suppression of the signals of insulin receptors,
leading to insulin resistance. Insulin is a hormone that converts
blood sugar to energy.
The ER has been compared to a synthetic machine of a cell, responsible
for processing proteins and fats. Scientists have also referred
to the ER as a factory for producing protein, as well as the site
where excess blood fats are processed.
When the body is bombarded with nutrients
the following occurs:
- Nutrients must be processed, stored and utilized
- The ER factory becomes overworked and starts sending SOS signals
- SOS signals tell the cells to dampen their insulin receptors
- The ER restrains normal responses to insulin
- Insulin can no longer clear sugar from the body
Another downfall of ER stress, besides obesity, is that it triggers
inflammation in cells. This inflammation can be linked to heart
disease.
Studies have revealed that if people can find a way to reduce ER
stress, generate less ER stress or find a way for the body to handle
stress more efficiently, type 2 diabetes might be easier to manage.
Science
October 15, 2004;306(5695):425-6
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