Islets of Langerhans Transplantation

Goal of Transplantation

When you agree to have a transplantation, from a donor of their Islets of Langerhans from the Pancreas, the goal is to infuse enough islets to control your blood glucose level thus removing the need for insulin injections.

A successful transplant can slow or prevent the progression of complications like nerve, blood vessel and eye changes associated with diabetes. It should help with good control of blood glucose levels.

Unless you are receiving a transplant from an identical twin that contains cells with exactly the same DNA your immune system will think the transplanted cells are foreign bodies and produce anti-bodies to kill them.

This requires the administration of drugs that supress your immune system. You must continue to use some of the drugs for the rest of your life.

For different diabetes events these mugs are great participant gifts.

Procedure

Transplanted islets come from the pancreas of a deceased donor. The  pancreas is subjected to a mixture of purified enzymes called collagenases that isolate islets from the other pancreatic tissue. The researchers inject the enzyme solution into the pancreatic duct that runs the length of the pancreas. This causes the pancreas to swell. The donor pancreas is then cut up into little chunks, transferred to a Ricordi's Chamber where digestion takes place until the islets are separated out from the exocrine gland tissue. 

The pancreas has both endocrine products and exocrine products. 

For our sake, we are interested in the endocrine products,  insulin and glucagon. They are hormones that are secreted into the blood circulatory system directly when called upon to control blood glucose levels. They are found in the islets.

The products that digest our food in the small intestine are enzymes. They enter the small intestine through ducts. When tissue does that the products are referred to as exocrine. (Pass into a duct system - not the circulatory system)

The islets are separated from the exocrine debris in a purification process. During the transplant procedure a catheter (tube) is carefully guided through the upper portion of your abdomen and into the hepatic portal vein of the liver. This provides the way the islets are placed into the body where they can begin to function.

It takes a little time for the islets to attach to the new blood capillaries and to produce insulin. As the new islets ramp up for production of insulin the physician may order many tests to check blood glucose levels after the transplant. You may need to continue injections of insulin to help you bridge the gap until the new cells take over.

Immune System Depression

Like everything else there is no free lunch. If you have to suppress the immune system, to prevent the immune system from destroying the islet cell from an unrelated donor, you leave your  body more susceptible to other diseases that may enter you body. Your physician can inform you of those possibilities.

Three drugs currently used to suppress the immune system are Daclizumab (Zenapax), Sirolimus (Rapamune) and Tacrolimus (Prograf). Two of the drugs, Sirolimus and Tacrolimus, you must take for life. In conclusion, immune system suppressant drugs are not a cure. They provide a comfort level to allow a transplant to do its thing. The alternative is the destruction of the transplanted cells.

Mis--diagnosis of Type II Diabetes

Type II Diagnosis and Type I Diagnosis - Cause for Concern?

The population in the U.S. is bordering on obesity. Obesity and lack of exercise are contributing factors in the onset of Adult Onset Type II diabetes.

Physicians routinely see patients with high blood glucose that are obese and inactive. They make a diagnosis of Type II diabetes that results in a program of treatment that doesn't make the patient feel better.

The reason the patients don't feel better is, in many cases, because they suffer from Type I diabetes. The protocol for treating Type I diabetes is different from Type II diabetes.

When the correct diagnosis is finally made the patient begins to feel much better.

Here is a link to an excellent article, published in todays Wall Street Journal, that is well written that addresses the problem that exists today.

Damage to Blood Capillaries in Diabetes

Capillary Problems and Blood Glucose

When a capillary narrows the flow decreases dramatically. If you halve the radius of a blood capillary the blood flow through the capillary decreases to one-sixteenth of its normal rate. 

This will cause an increase in blood pressure (think hypertension) which can lead to ruptured blood vessels. In the brain region, a stroke is possible. Heart attacks can occur with lessened blood flow to the arteries that supply the heart muscle.

Blood vessels capillary networks in diabetics are unable to relax well. Researchers believe  altered proteins involved in relaxation are affected by a glucose-derived molecule. The net result is possible hypertension, chance of strokes and increased obesity.

When insulin is not present in the circulatory system the level of glucose remains high in our circulatory system. It begins to decrease the level of nitric oxide, a chemical that increases the diameter of blood vessels. The continual exposure to high blood glucose levels leads to the eventual narrowing of the blood vessel system.

I  have not read this book. If you do read the book tell others the pros and cons.

Unfortunately, in diabetes, when a person has their diabetes under control, a small percentage of the glucose is converted to a sugar type that can modify the proteins.

In your blood vessels this modified glucose competes with a mechanism called phosphorylation that modifies an enzyme that makes possible the formation of  nitric oxide. Its name tells you what it does. Its called a nitric oxide synthase. It catalyzes the formation of nitric oxide, a blood vessel dialator. The modified-glucose wins out in the competition with phosphorylation and negates the formation of nitric oxide. Net result is constricted blood vessels that increase a diabetics chance for developing high blood pressure, strokes and heart attacks.

Researchers are focusing on blocking the mechanism that prevents the formation of the modified-glucose molecule. If that is successful the effect on nitric oxide production will cease and become normal and the danger from hypertension, stroke and heart attacks will diminish.

Interesting point to remember about nitric oxide is the nitro glycerine tablet a person takes to dilate their heart blood vessels in a heart attack. 

Glucose - Enzymes - Food for Thought

Glucose and Enzymes

All chemical reactions require enzymes to catalyze the reactions. How are enzymes produced?

In cells the nucleus, an organelle, contains DNA that contains our genome. The genome contains all the information that constitutes you. It is unique.





All of us basically share a likeness (physical, chemical, psychological, etc.)  to all that we are. Very small differences make us unique.

When a cell receives a message, from somewhere in our body ,that glucose is on its way to supply a basic ingredient for energy production our cells prepare to receive the glucose.

It seems simple. Glucose appears outside the cell, enters the cell, and produces energy that is immediately used or is stored for future use. There are two ways glucose can enter the cell. Both work when a person doesn't have diabetes.

Type I Diabetes occurs early in life and the cause is lack of insulin.

Type II Diabetes occurs later in life and insulin production is available. The factor that transports insulin into the cell is missing. 

The cell needs a factor present for glucose to enter the cell. In the nucleus of a cell there are two important molecules. DNA and RNA. Like a blueprint, the DNA has a code for the manufacture of the enzyme. It replicates the code for RNA. RNA receives the information and forms a complementary code. It begins the manufacture of a faulty trigger that doesn't insulin to enter the cell interior.

All this takes place in the nucleus and inner cell machinery. Here is where trouble can begin for a Type II diabetic. What if the DNA message has changed? What caused the message to change? How does the body compensate for the inability of insulin to function? Lots of questions.

If the cell manufactures a faulty factor, from information received from the nucleus, it won't catalyze the reaction that makes it possible for glucose to enter the cell. The result is the loss or ability to activate the factor that facilitates the cell membrane to ferry the glucose into the cell interior.

It doesn't matter if the levels of insulin are normal. Glucose that doesn't enter a cell means the glucose in the blood begins to rise. There is a solution from the kidneys. The second way glucose can enter a cell, and out of the bloodstream, is based on the sodium/potassium pump. The Sodium+/Potassium+ active transport Pump allows glucose, that is reabsorbed from the kidneys, to piggy-back with the Sodium with its transporter. The Sodium Transporter helps glucose enter the cell. Even though normal amounts of insulin are available but can't function to lower blood glucose the secondary active transport system is available.

To make the removal of glucose easier diet plays a role in the Type II diabetic. That helps control blood glucose and allows normal levels of glucose in the bloodstream.

With you always in understanding the confusing relationship of glucose, insulin and secondary active transport systems in the kidneys.