1. Control of Blood Sugar
Diabetes Mellitus

2. Maintaining Glucose Homeostasis
Goal is to maintain blood sugar levels between ~ 70 and 110 mg/dL
Two hormones play a role in maintaining glucose homeostasis:
Insulin
Glucagon
Both are pancreatic hormones

3. Lowering Blood Glucose Levels
Blood glucose levels rise due to eating a carbohydrate containing meal
In response, the pancreas releases insulin into the blood.
Beta cells of the pancreas release insulin

4. Lowering Blood Glucose Levels
Insulin
Binds to insulin receptors on cells.
Cells allow glucose to enter
Stimulates liver and muscle cells to store glucose as glycogen
Stimulates excess glucose to be converted into fat.
As a result, blood glucose levels drop.

5. Raising Blood Glucose Levels
Blood glucose levels drop as cells use glucose.
In response, the pancreas releases glucagon into the blood.
Alpha cells of the pancreas release glucagon

6. Raising Blood Glucose Levels
Glucagon:
Stimulates liver cells to break down glycogen and release the glucose into the blood.
As a result blood glucose levels rise.

7. Diabetes Mellitus
Diabetes mellitus refers to a group of metabolic disorders in which the body is unable to regulate high blood glucose levels.

8. Diabetes Mellitus Two common forms: Type 1 diabetes Type 2 diabetes
Other names:
“Juvenile” diabetes
Insulin dependent diabetes mellitus (IDDM)
Type 2 diabetes
“Adult onset” diabetes
Noninsulin dependent diabetes mellitus (NIDDM)

9. Incidence of Diabetes Type 1 Diabetes Type 2 Diabetes
5-10 % of diabetics
Onset is generally before age 20
Average age of onset ~12
Type 2 Diabetes
90-95% of diabetics
Onset is generally between ages or after age 40

10. Type 1 Diabetes Possible causes: Autoimmune disorder
Genetic component
Immune system destroys beta cells of pancreas
May also be caused by a viral infection that damages the pancreas

11. Type 1 Diabetes Pancreas is unable to make/secrete insulin.
Glucose cannot enter cells  hunger
Blood glucose levels rise
Glucose “spills” into the urine
Water moves into blood
Frequent need to urinate
Thirsty

12. Type 1 Diabetes
Cells use fats and proteins as an energy source, results in:
Weight loss  hunger
Ketones produced (due to “overuse” of fats for energy)  potential for diabetic acidosis

13. Type 1 Diabetes Diabetic acidosis (ketosis) Ketones in breath
Ketones in blood and urine
 can lead to diabetic coma

14. Type 1 Diabetes Treatment Insulin shots or pump
Highly regulate intake of carbohydrates
Consistent pattern of moderate carbohydrate intake to minimize fluctuations in blood glucose
Closely monitor blood glucose levels

15. Type 2 Diabetes Associated with obesity Genetic component
As gain weight, cells make fewer insulin receptors
Insulin doesn’t bind as well to receptors made
Genetic component
More common as age

16. Type 2 Diabetes Fewer insulin receptors on cells
Less insulin binds to cells
Glucose enters cells SLOWLY
Blood glucose levels remain elevated
Glucose “spills” into the urine
Water moves into blood
Frequent need to urinate
Thirsty

17. Type 2 Diabetes Glucose enters cells slowly…
No need to use proteins or fats for energy
Hungry
Eat more  gain weight
Exacerbates the problem

18. Type 2 Diabetes Pancreas continues to make insulin
Often in large amounts to compensate for the insulin resistance of cells
May get to point where pancreas cannot keep up with the body’s needs and insulin is required.

19. © 2008 Thomson - Wadsworth

20. Type 2 Diabetes Recommendations Lose weight Exercise
Even moderate weight loss can help
Exercise
Increases number of insulin receptors
Improves binding of insulin to the receptors
Helps with weight loss

21. Chronic Complications of Diabetes
Regular high blood glucose levels result in
Cells making sugar alcohols
Glucose binds to proteins on cells, damages cells
Results in:
Damage to blood vessels and nerves
Slowed healing
Unaware of wounds…… amputation
Kidney damage  kidney failure
Damage to cells of eyes  blindness

22. Chronic Complications of Diabetes
Other:
Increased risk of:
Coronary heart disease
Elevated blood lipid levels
Hypertension
Adults with diabetes have heart disease and stroke death rates ~ 2 to 4 times higher than adults without diabetes.

23. 2012 US Data 9.3 % of U.S. population has diabetes
Age 65 or older ~25% have diabetes
1 in 6 overweight adolescents aged have pre-diabetes
More Statistics

25. Diabetes by race in the U.S.
Source: CDC/NCHS

26. Diabetes by education in the U.S.
Source: CDC/NCHS