Pancreas : Diabetes, Cystic Fibrosis

by Food and Drug Administration (FDA)

The human pancreas, an elongated, flattened gland behind the stomach, is involved in or affected by a number of diseases, including diabetes mellitus, cystic fibrosis, pancreatitis, and pancreatic cancer. These conditions are diagnosed and treated with products regulated by the Food and Drug Administration.

The pancreas is composed of two major types of tissues:

Exocrine tissue (acini), which secretes digestive enzymes via the pancreatic duct into the duodenum (part of the small intestine leading from the stomach)

Endocrine tissue (islets of Langerhans), which produces and secretes the hormones insulin and glucagon directly into the blood.

Endocrine tissue contains alpha, beta and delta cells. Beta cells produce insulin and alpha cells produce glucagon. These hormones regulate blood glucose levels. Delta cells secrete the hormone somatostatin, which inhibits insulin and glucagon secretion.

Diabetes

A deficiency of insulin in the body results in diabetes mellitus, which affects about 13 million individuals in the United States. It is characterized by a high blood glucose (sugar) level and glucose spilling into the urine due to a deficiency of insulin. As more glucose concentrates in the urine, more water is excreted, resulting in extreme thirst, rapid weight loss, drowsiness, fatigue, and possibly dehydration. Because the cells of the diabetic cannot use glucose for fuel, the body uses stored protein and fat for energy, which leads to a buildup of acid (acidosis) in the blood. If this condition is prolonged, the person can fall into a diabetic coma, characterized by deep labored breathing and fruity-odored breath.

There are two types of diabetes. In Type I diabetes, formerly called juvenile-onset diabetes, the pancreas cannot produce insulin. People with Type I diabetes must have daily insulin injections. But they need to avoid taking too much insulin because that can lead to insulin shock, which begins with a mild hunger. This is quickly followed by sweating, shallow breathing, dizziness, palpitations, trembling, and mental confusion. As the blood sugar falls, the body tries to compensate by breaking down fat and protein to make more sugar. Eventually, low blood sugar leads to a decrease in the sugar supply to the brain, resulting in a loss of consciousness. Eating a sugary food can prevent insulin shock until appropriate medical measures can be taken.

Type II diabetes, formerly called adult-onset diabetes, can occur at any age. The pancreas can produce insulin, but the cells do not respond to it.

For many years, treatment was insulin therapy for Type I and oral sulfonylureas and/or insulin therapy for Type II.

Metformin (glucophage) was the first antidiabetic drug approved by FDA (May 1995) for the treatment of Type II diabetes since the oral sulfonylureas were introduced in 1984. Metformin promotes the use of insulin already in the blood. This May 1995 approval was followed by the September 1995 approval of another antidiabetic drug, Acarbose (precose), in September 1995. It slows down the digestion and absorption of complex sugars, which reduces blood sugar levels after meals.

Before 1982, insulin was purified from beef or pork pancreas. This was a problem for those diabetics allergic to animal insulin. Researchers produced a synthetic insulin called humulin. Approved by FDA in 1982, it was the first genetically engineered consumer health product manufactured for diabetics. Synthetic insulins can be produced in unlimited quantities.

Another possible treatment for diabetes includes surgically replacing the pancreas' endocrine tissues (islets of Langerhans) with healthy islet of Langerhans tissue grafts. Since 1988, 45 patients worldwide have undergone successful transplantation.

Cystic Fibrosis

The major problem of cystic fibrosis, the number one genetic killer disease of children in the United States, is that the body overproduces thick, sticky mucus. The mucus blocks the pancreatic ducts, which impedes the flow of the pancreatic juices from the pancreas into the duodenum of the small intestines. Food cannot be properly digested. Without treatment, children with cystic fibrosis suffer from malnutrition and constant diarrhea; their average life expectancy is 21. Pancreatic enzyme preparations are usually used to minimize the disease's effects on the pancreas.

Pancreatic juices contain enzymes for digesting all three major food types (proteins, carbohydrates and fats), as well as quantities of bicarbonate ions, which play an important role in neutralizing the acid emptied by the stomach into the duodenum. The most important enzyme for fat digestion is pancreatic lipase, which is capable of changing fat into glycerol fatty acids and cholesterol. Hormones regulate pancreatic secretions. Food enters the small intestine. The hormones secretin and cholecystokinin cause the pancreas to create large quantities of fluid containing bicarbonate ions, which neutralizes the acid stomach contents.

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.