ing weight and developing diabetes. later in life, according to a study of In type 1 diabetes, the immune system destroys many …
Calorie-Coated Diabetes
What is biotech doing to prevent and treat diabetes?
GUSTO/SCIENCE PHOTO LIBRARY
Hold the soda It may taste good now, but soda pop is one of the biggest contributors of calories–as sugar–to the average American diet And too much of it increases the risk of gaining weight and developing diabetes later in life, according to a study of 91,000 nurses out of the Harvard School of Public Health Sugar itself is not bad In fact, its the basic source of energy for your body Without it, your cells would not produce energy Sugar in the bloodstream stimulates particular cells, called beta cells, to produce insulin, which increases the flow of sugar from the bloodstream to muscles and other cells to be used as fuel Insulin also tells the liver to take sugar out of the bloodstream to store for later use When sugar levels fall, insulin levels fall and levels of something called
glucagon rise, signaling the liver to release sugar Types of Diabetes In type 1 diabetes, the bodys immune system destroys the insulinproducing beta cells in the pancreas With type 1 diabetes, people get insulin through shots or a pump so they can process sugar In type 2 diabetes, the body
produces insulin, but not enough or the cells cant use it well Of people with diabetes, 90 to 95 percent have this type Type 2 has been more common among people over 50, but is now occurring more often in younger people Obesity and lack of exercise are major risk factors for this type of diabetes Genetic factors may also play a role Diabetes can be controlled, but even well-controlled diabetes has consequences Diabetes affects blood
glucose levels, making them too high or too low When this happens, you might feel sleepy, dizzy, confused, or have blurred vision This may not be serious when youre listening in class, but it could be fatal when youre driving If your blood glucose level is too low, you might make bad choices, not focus on your driving, or lose control of your car Long-term complications can lead to blindness, heart disease, kidney disease, and even amputation Biotech Possibilities Researchers in Chicago believe the scientific community knows enough now to treat most diabetes patients with therapies that involve changing cells themselves, cell-based therapy They have formed an international project focused on a cure for diabetes in five years
Factoid
About 182 million
Americans, or 63 percent of the population, had diabetes in 2002, and the numbers are rising Lifestyle patterns youre setting now, as well as genetics, may lead to or lower the risk youll get diabetes
6 Biotechnology and OBESITY
Making Transplants Easier
A current but very difficult treatment for diabetes is to transplant a pancreas or its beta cells Beta cells are part of the endocrine system and produce insulin The transplant attempts to replace cells destroyed by the immune system The beta cells can sometimes be injected so they lodge in the liver and produce insulin But it is difficult to keep the immune system from continuing to destroy the new beta cells, too In April 2005 for the first time doctors transplanted beta cells from a live donor, a mother to her daughter Biotechnologists are developing immunosuppressive drugs to prevent the body from destroying its own beta cells Gene therapy genetically modifies beta cells before transplantation to protect them from the immune system LV
Cell-based therapies being researched include manipulating different kinds of cells to produce insulin This is possible because every cell has the same genetic information as all other 
cells;
each cell turns on a different part according to the kind of cell it is Currently, advanced medical treatments can sometimes transplant insulin-producing cells into the body, but many of these cells die or are rejected Other gene therapy includes modifying these cells before transplantation so fewer die In type 1 diabetes, the immune system destroys many components of the insulin-producing beta cells in the pancreas An arm of biotechnology called immunogenetics concentrates on interfering with the processes that destroy these cells Genetic studies are testing members of families with diabetes for genes that increase susceptibility or that protect against diabetes This type of screening led to the discovery of insulin-producing cells in the thymus, where insulin might be used to help train or screen maturing immune system cells to recognize self versus other, a critical area of malfunction in autoimmune diseases These cells have also, unexpectedly, been found in fat and bone marrow cells In other areas of biotech, molecular biologists are studying how to interfere with the signaling proteins on islet cell surfaces that make them susceptible to attack by the immune system In
bioinformatics, researchers are using computers to manipulate complex genomic information to model a non-obese diabetic mouse in researching type 1 diabetes Researchers in biotherapeutics are developing such treatments as antibodies that protect insulin-producing cells from immune system attack; drugs that stop the immune system from destroying cells or make cells more receptive to insulin; a new drug modeled on the saliva of a Gila monster that stimulates insulin production Biotechnologists have isolated the active compounds in plants that help the body process glucose, a type of sugar Drug makers are even developing insulin powder that people would inhale rather than inject Bioengineering applies
engineering principles to sensors for administering insulin or monitoring blood sugar levels Bioengineering is also applied to treating complications from the disease such as blindness Tiny electrode arrays on a thin sheet of silicon make artificial retinas for diabetics who are blind People working in biotechnology are among those trying to prevent and treat diabetes, a disease that is an increasing concern as more people get too heavy –Linda Voss
Insulin Production in a Beta Cell
in the Pancreas Mitochondria which provide cells with energy are green, and the nucleus is purple The folded membrane below the nucleus is the endoplasmic reticulum, which divides the cell into compartments Insulin made in the cell is packaged in secretory granules blue balls in pink saucers These migrate through the cell and are secreted directly into a blood capillary bottom, containing red blood cells
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Cell Biology of Insulin Response
Insulin Glucose Insulin receptor
? ? ?
Normal Cell
This is a normal cell Insulin is present and is taken into the cell to facilitate proper glucose uptake and metabolism
Closed glucose transporter Open glucose transporter
Type 1 Diabetes Cell
In type 1 diabetes, insulin is not produced; so, there is nothing to signal the cells to take in glucose and metabolize it
Type 2 Diabetes Cell
In type 2 diabetes, insulin is present, but the signal for proper glucose uptake and metabolism is lost The problem could be in the insulin itself or in any one of the proteins involved in glucose uptake and metabolism Your World 7
Source:co.pierce.wa.us
