Question for a medical doctor. What causes Insulin resistance on a cellular level?

Question

Please READ the question. I know what insulin resistence is. I want a medical doctor to tell me exactly what happens on a cellular level and why. I would like to hear about specific receptors and such

Answer 1

I'm a dental student not a medical doctor but here's something I found off wikipedia that should start you off:

"At the cellular level, down-regulation of insulin receptors occurs due to high circulating insulin levels, apparently independently of insulin resistance.[5] Inflammation also contributes to insulin resistance. Mice without JNK1-signaling do not develop insulin resistance under dietary conditions that normally produce it.[6] [7]

Some research has shed light on a complex interaction between elevated free fatty acids and inflammatory cytokines seen in obesity activating Protein Kinase C isoform theta. PKC Theta inhibits Insulin Receptor Substrate (IRS) activation and hence prevents glucose up-take in response to insulin."

Answer 2

If you have pre-diabetes or diabetes, chances are that you’ve heard of the medical term insulin resistance syndrome or metabolic syndrome. Insulin resistance or metabolic syndrome describes a combination of health problems that have a common link -- an increased risk of early heart disease.

The cluster of medical conditions that make up the insulin resistance syndrome or metabolic syndrome places a person at risk of developing type 2 diabetes and atherosclerosis (hardening of the arteries). It is estimated that 70 to 80 million Americans have the combination of diseases caused by insulin resistance or metabolic syndrome.

Diseases caused by insulin resistance include the following:

Obesity

Type 2 diabetes

High blood pressure

Abnormal cholesterol levels

Heart disease

Polycystic ovarian syndrome



What Is Insulin Resistance?

Normally, food is absorbed into the bloodstream in the form of sugars such as glucose and other basic substances. The increase in glucose in the bloodstream signals the pancreas (an organ located behind the stomach) to increase the secretion of a hormone called insulin. This hormone attaches to cells, removing glucose from the bloodstream so that it can be used for energy.

In insulin resistance, the body's cells have a diminished ability to respond to the action of the insulin hormone. To compensate for the insulin resistance, the pancreas secretes more insulin.

People with this syndrome have insulin resistance and high levels of insulin in the blood as a marker of the disease rather than a cause.

Over time people with insulin resistance can develop high sugars or diabetes as the high insulin levels can no longer compensate for elevated sugars.

What Are The Health Components of Insulin Resistance Syndrome?

The health components of insulin resistance syndrome include:

Impaired fasting glucose, impaired glucose tolerance or type 2 diabetes. This occurs because the pancreas is unable to turn out enough insulin to overcome the insulin resistance. Blood glucose levels rise and diabetes is diagnosed.

High blood pressure. The mechanism is unclear, but studies suggest that the worse the blood pressure, the worse the insulin resistance.

Abnormal cholesterol levels. The typical cholesterol levels of a person with insulin resistance are low HDL, or good cholesterol, and high levels of another blood fat called triglyceride.

Heart disease. The insulin resistance syndrome can result in atherosclerosis (hardening of the arteries) and an increased risk of blood clots.

Obesity. A major factor in the development of insulin resistance syndrome is obesity--especially abdominal obesity or belly fat. Obesity promotes insulin resistance and negatively impacts insulin responsiveness in a person. Weight loss can improve the body's ability to recognize and use insulin appropriately.

Kidney damage. Protein in the urine is a sign that kidney damage has occurred, although not everyone uses this component to define the insulin resistant syndrome.

How Is Insulin Resistance Syndrome Diagnosed?

There is no simple test to diagnose insulin resistance syndrome. Rather, your doctor may suspect the syndrome if you have the following health risk factors:

More than one parent or sibling who has type 2 diabetes, hypertension or cardiovascular disease.

Obesity or overweight (BMI -- body mass index -- above 25).

More fat around the waist than around the hips (an apple shape).

Age greater than 40 years

Gestational diabetes when pregnant.

A history of a condition called polycystic ovary syndrome (PCOS).

Pre-diabetes.

Are a member of certain ethnic groups (Latino, Blacks or Native American).

The current epidemic of obesity in children also puts them at risk for the development of the insulin resistance syndrome.

What's The Treatment for Insulin Resistance Syndrome?

Specific prescribed medications such as Glucophage (metformin), Actos (pioglitazone) and Avandia (rosiglitazone) are all approved to treat the insulin resistance that occurs with type 2 diabetes. These drugs make your body more sensitive to the actions of insulin. Multiple drugs, such as cholesterol-lowering drugs or anti-hypertensive drugs are usually necessary to treat the different conditions that are part of the insulin resistance syndrome.

Is Insulin Resistance Syndrome Preventable?

Yes. If you live a healthy lifestyle, you may be able to avoid getting insulin resistance syndrome and associated diseases. Here are some tips to prevent insulin resistance or metabolic syndrome:

Exercise. Try walking 30 minutes a day for at least 5 days a week (exercise can be divided into 3 separate periods of 10 minutes each)

Stay at a healthy weight

Eat right. A healthy balanced and caloric restricted diet is recommended.

Answer 3

Insulin resistance occurs really mostly in obese people. it is where insulin is released in sufficient amounts but just isnt working properly.

there are several reasons and things going on. When people store fat around their middle, the fat is more metabolically active than fat in the limbs and this is why it can cause insulin resistance. Basically it releases a lot of fatty acids into the blood. it stimulates the liver to release glucose in to the blood, and prevents muscle from taking up glucose = very high glucose levels, with insulin levels equally high, delayed and exaggerated response, and insulin not doing its job in the enlarged cells of obese people.

hope it helped!