New study finds the mechanism for insulin resistance leading to type 2 diabetes.
Earlier work by Joshua Knowles, MD, PhD, an assistant professor of cardiovascular medicine at Stanford, and his team showed the connection of a human gene, NAT2, variant with insulin resistance in humans.
The fact that type 2 diabetes was caused by insulin resistance was known to researchers for decades. However, the cause for this phenomenon was a mystery.
Insulin, a hormone secreted by the pancreas, helps fat and muscle cells take up glucose from the blood. Insulin resistance is caused when human cells don’t respond to insulin, resulting in the build up of glucose in the blood and subsequently leading to the production of even more insulin.
“We’ve identified a mechanism for insulin resistance that involves a gene that ties insulin resistance to mitochondrial function, “ said Knowles.
Scientists at the Stanford University School of Medicine and the University of Wisconsin have begun to find the connections between a gene, mitochondria, insulin resistance, and how well the body’s metabolism functions in causing diabetes.
Suppressing a similar gene in mice called Nat1, causes metabolic dysfunction, such as lower insulin sensitivity and higher levels of blood sugar, insulin and triglycerides. In addition, mice without the Nat1 gene gained more weight and showed a decreased ability to use fat for energy.
This new study reveals that suppressing the expression of the Nat1 gene in mice hinders the function of mitochondria. These cell structures make ATP, the energy of cells, without which the cells cannot survive.
Individuals with Insulin resistance don’t necessarily develop type 2 diabetes. However, the condition will result in decreased uptake of sugar by muscle and fat cells leading to cardiovascular disease, inflammation, polycystic ovary syndrome, fatty liver diseases and other health conditions.
Severe Insulin resistance leading to damaged body tissues is common. A study in 2015 estimated that close to 35 percent of US adults are insulin-resistant to a degree to be at a higher risk for diabetes and cardiovascular disease.
Knowles said, the reasons for this skyrocketing increase in the US are poor diet and sedentary habits.