Reply #21: Diabetes education, if you need it [View All]

[TechBear_Seattle]

Excuse me a moment while I put on my "pendantic hat." :hi:

There are two major types of diabetes, formerly known as "juvenile diabetes" and "adult onset diabetes" and know called simply Type 1 and Type 2. The change in name was made about 15 years ago to reflect the cause of the diabetes rather than the age at which it developed. While both types have different causes, they have the same effect: chronically high blood sugar, which causes all sorts of problems.

When a person eats carbohydrates -- fructose, table sugar, starch, whatever -- the liver will convert some of those carbs into glucose and release it into the bloodstream. The rest is bound with fat to create glycogen, which is stored in the liver. Glycogen is converted into glucose and released as the body needs more energy.

In a healthy individual, a raise in the level of glucose in the blood prompts the pancreas to release insulin into the blood, produced by pancreatic cells called the Islets of Langerhans. Insulin is a long, curled chain of protein. When one end of the insulin molecule "bumps into" a glucose molecule, that end of insulin will "snap" like a trap closing, grabbing hold of the glucose. That reconfigures the other end of the insulin into a trap that fits a type of receptor put out by cells needing glucose. The insulin will eventually bump into one of these receptors and snag; the cell then "reels in" the receptor, harvests the glucose and disassembles the insulin for material to build other proteins.

Glucose is an extremely energetic molecule, which is why every active lifeform on this planet has evolved to use it as an energy source. In high concentrations, it acts like an acid and can cause serious damage to the cells. It will etch away at the inside of the blood vessels, creating places where blood clots can form and where cholesterol can accumilate. In many cases the damage can be repaired, but nerve cells and cells in the retina can not be repaired and so result in nerve damage and blindness. High blood sugar interferes with blood clotting and cell repair, which means wounds are more slow to heal. Adding insult to injury, high blood sugar also causes problems with parts of the immune system and provides a luscious buffet to many different bacteria, making illness a very serious problem. The body tries to remove excess glucose in the urine, but the glucose can also cause damage to kidney cells. Also, chronic high blood sugar can overwork the kidneys; combined with cellular damage, it can lead to the kidneys "burning out." All of this is why diabetes is the leading cause in the United States for blindness, kidney failure, strokes and non-accident related amputations (caused by gangrene infections), and why diabetics are high on the list to get immunizations.

Type 1 diabetes is caused when the body does not produce enough insulin to handle the amount of glucose, and represents about 5% to 7% of all cases of diabetes in the United States. The majority of T1 is caused by an auto-immune disease, where the body's immune system attacks and destroys the Islets of Langerhans (IoL.) In this situation, depending on the severity, the IoL are destroyed anywhere from before birth to early adulthood, leading to diabetes. This form of T1 is what the research mentioned in the OP addresses: by finding the gene that causes this auto-immune response, it becomes possible to fix the condition and either prevent further damage or allow for the transplantation of healthy IoL or even a whole pancreas. Most other cases of T1 are caused by failure of the pancreas due to aging or disease. Because people with T1 do not produce enough insulin, they must take it manually through injection or the use of an insulin pump.

Type 2 diabetes is caused when the body does not use the insulin it has, and represents 90% to 95% of all cases of diabetes in the United States. There are several reasons why T2 might develop. The most common one is that the cells are "full" and do not put out the insulin receptors, allowing insulin (and glucose) to remain in the bloodstream until the kidneys get annoyed and remove it. This situation seems to be closely related to metabolic rate and/or obesity (research is still unclear on which is the primary cause.) The research mentioned in the OP will not help with T2, but may open other avenues of research that will lead to effective treatments for other kinds of diabetes.