Homeostasis and Diabetes L3

What is Homeostasis? The maintenance of a constant internal environment, despite external changes is called Homeostasis

Body cells work best if they have the correct Body cells work best if they have the correct Temperature Temperature Water levels Water levels Glucose concentration Glucose concentration Your body has mechanisms to keep the cells in a constant environment. Your body has mechanisms to keep the cells in a constant environment.

Where is the pancreas?

Pancreatic endocrine functions  cells: make insulin (stores glucose)  cells: make insulin (stores glucose) = ¾ of the cells; secrete Insulin  cells: make glucagon to (mobilize glucose)  cells: make glucagon to (mobilize glucose) ¼ of the cells; secrete Glucagon The pancreas also secretes enzymes needed in digestion The pancreas also secretes enzymes needed in digestion

Insulin and the 3-”G’s” Insulin: (anabolic). Initiates buildup of glucose to store as glycogen. Insulin: (anabolic). Initiates buildup of glucose to store as glycogen. 1. Glucagon: (catabolic). Breaks down stored glycogen into glucose. 1. Glucagon: (catabolic). Breaks down stored glycogen into glucose. 2. Glycogen is stored form of glucose. 2. Glycogen is stored form of glucose. 3. Glucose: usable form of sugar present in blood. 3. Glucose: usable form of sugar present in blood.

Controlling Glucose levels Your cells (muscles, brain, etc) need an exact level of glucose in the blood. (normal serum level 65 – 105 mg) Your cells (muscles, brain, etc) need an exact level of glucose in the blood. (normal serum level 65 – 105 mg) Excess glucose gets turned into glycogen in the liver and muscles Excess glucose gets turned into glycogen in the liver and muscles Blood glucose levels are regulated by 2 hormones (chemical messengers) from the pancreas called: Blood glucose levels are regulated by 2 hormones (chemical messengers) from the pancreas called:InsulinGlucagon

Normal Maintenance of Blood Glucose Levels Eat a meal: Eat a meal: Pancreas detects increased glucose levels in blood and secretes INSULIN Pancreas detects increased glucose levels in blood and secretes INSULIN This results in uptake of GLUCOSE by: This results in uptake of GLUCOSE by: Cells that need it for energy (including brain) Cells that need it for energy (including brain) Liver and muscle cells to be stored as glycogen Liver and muscle cells to be stored as glycogen Pancreas stops release of Insulin Pancreas stops release of Insulin Glucose levels return to normal (80-120) Glucose levels return to normal (80-120)

Time Glucose Concentration Meal eaten Insulin is produced and glucose levels fall to normal again. Glucose levels rise after a meal. Normal

Normal maintenance, cont. Insulin secretion regulated by Negative Feedback of blood glucose levels Insulin secretion regulated by Negative Feedback of blood glucose levels High blood glucose stimulates insulin secretion High blood glucose stimulates insulin secretion Low blood glucose inhibits insulin secretion Low blood glucose inhibits insulin secretion

If there is too much glucose in the blood, Insulin tells the liver to convert some of it to glycogen Glycogen Insulin Glucose in the blood

Normal Maintenance of Blood Glucose Levels, cont. Blood glucose drops due to NOT eating Blood glucose drops due to NOT eating Pancreas detects and releases glucagon Pancreas detects and releases glucagon stimulates the release of glycogen (broken down to glucose) stimulates the release of glycogen (broken down to glucose) Glucose is released into the blood and levels return to normal. Glucose is released into the blood and levels return to normal.

If there is not enough glucose in the blood, Glucagon tells the liver to convert glycogen into glucose. Glycogen Glucagon Glucose in the blood

Normal Maintenance, cont. Release of Glucagon also regulated by Negative Feedback mechanism sensitive to glucose levels in blood. Release of Glucagon also regulated by Negative Feedback mechanism sensitive to glucose levels in blood. Low blood sugar stimulates glucagon secretion Low blood sugar stimulates glucagon secretion High blood sugar inhibits glucagon secretion High blood sugar inhibits glucagon secretion

Diabetes Some people do not produce enough insulin. Some people do not produce enough insulin. When they eat food, the glucose levels in their blood cannot be reduced. When they eat food, the glucose levels in their blood cannot be reduced. This condition is known as DIABETES. This condition is known as DIABETES. Diabetics sometimes have to inject insulin into their blood. They have to be careful of their diet. Diabetics sometimes have to inject insulin into their blood. They have to be careful of their diet.

Time Glucose Concentration Meal eaten Insulin is not produced so glucose levels stay high Glucose levels rise after a meal. Diabetic

The glucose in the blood increases, Glycogen Insulin Glucose in the blood but there is no insulin to tell the liver to convert it into glycogen. Glucose concentration rises to dangerous levels.

Hyperglycemia= high blood glucose levels Drowsy Drowsy Flushed Flushed Thirsty Thirsty

Hypoglycemia= LOW blood sugar Glucagon: causes release of glucose from liver Glucagon: causes release of glucose from liver breakdown of glycogen to glucose breakdown of glycogen to glucose

Hypoglycemia Weak, sweaty Weak, sweaty Confused/irritable / disoriented Confused/irritable / disoriented

Diabetes Mellitus Complications Major health problem US/worldwide Major health problem US/worldwide Complications [Poor blood vessels/circulation (PVD] Complications [Poor blood vessels/circulation (PVD] Blindness (L3: retinal proliferation, macular degeneration) Blindness (L3: retinal proliferation, macular degeneration) Renal failure Renal failure Amputations Amputations Cardiovascular disease (heart attack) Cardiovascular disease (heart attack) Cerebrovascular disease (strokes ) Cerebrovascular disease (strokes ) [OB/neonatal complications] [OB/neonatal complications] Diabetic neuropathy Diabetic neuropathy Erectile dysfunction Erectile dysfunction

Diabetes Mellitus The good news: Blood glucose control reduces complications of Diabetes! Blood glucose control reduces complications of Diabetes!

What is going on? Absence (or ineffectiveness of ) insulin Absence (or ineffectiveness of ) insulin Cellular resistance Cellular resistance Cells can’t use glucose for energy Cells can’t use glucose for energy Starvation mode Starvation mode Compensatory breakdown of body fat/protein (ketone breath: smells like alcohol) Compensatory breakdown of body fat/protein (ketone breath: smells like alcohol)

Side Effects HYPERGLYCEMIA: fluid/electrolyte imbalance. HYPERGLYCEMIA: fluid/electrolyte imbalance. Sodium, chloride, potassium excreted (frequent urination) Sodium, chloride, potassium excreted (frequent urination) Dehydration (thirsty all the time) Dehydration (thirsty all the time) cells are starving, so person feels hungry despite eating huge amounts of food. Starvation state remains until insulin is available. (eats too much) cells are starving, so person feels hungry despite eating huge amounts of food. Starvation state remains until insulin is available. (eats too much)

Type I Diabetes MUST HAVE INSULIN WHICH IS INJECTED!!! Can also have oral medications too to help. MUST HAVE INSULIN WHICH IS INJECTED!!! Can also have oral medications too to help. Cause: autoimmune-happens at birth or by teen years. (AKA:juvenile diabetes) Cause: autoimmune-happens at birth or by teen years. (AKA:juvenile diabetes) Beta cell destruction in genetically susceptible person Beta cell destruction in genetically susceptible person Some viral infections: can destroy beta cells Some viral infections: can destroy beta cells

Type II Diabetes Can have insulin but usually given oral meds. Can have insulin but usually given oral meds. Cause/Who gets it- usually adult onset but a problem on the rise in children Cause/Who gets it- usually adult onset but a problem on the rise in children Reduction in ability of most cells to respond to insulin Reduction in ability of most cells to respond to insulin Poor control of liver glucose output Poor control of liver glucose output Decreased beta-cell function (eventual failure) Decreased beta-cell function (eventual failure)

Risk Factors for Type II Major risk factors Major risk factors Family history Family history Obesity Obesity Origin (Afro-American, Hispanic, Native American, Asian-American) Origin (Afro-American, Hispanic, Native American, Asian-American) Age (older than 45) Age (older than 45) History of gestational diabetes History of gestational diabetes High cholesterol High cholesterol Hypertension Hypertension

Preventions Prevention of effects: combination approach Prevention of effects: combination approach Increased exercise Increased exercise Decreases need for insulin Decreases need for insulin Reduce calorie intake Reduce calorie intake Improves insulin sensitivity Improves insulin sensitivity Weight reduction Weight reduction Improves insulin action Improves insulin action

Triad of Treatment Diet Medication Oral hypoglycemics Insulins Exercise

Oral medications Stimulate pancreas to secrete insulin Stimulate pancreas to secrete insulin Glyburide Glyburide Many others Many others May need to add insulin in times of stress May need to add insulin in times of stress

Insulin Moves glucose into cells (thus acts like growth hormone in a way) Moves glucose into cells (thus acts like growth hormone in a way) Needs to be injected Needs to be injected

Insulin preparations Rapid acting Short acting (regular) Intermediate acting (NPH) Long acting

Some things to know…L3 Dawn Phenomenon and Somogi’s effect Dawn Phenomenon and Somogi’s effect Dawn phenomenon Dawn phenomenon Blood sugar rises in early morning Blood sugar rises in early morning Somogi’s (rebound) effect Somogi’s (rebound) effect Blood sugar rise in morning as reaction to hypoglycemic time during the night Blood sugar rise in morning as reaction to hypoglycemic time during the night

Some things to know…L2/L3 Diabetic foot care Diabetic foot care Dry, cracked skin + poor circulation could = loss of a limb Dry, cracked skin + poor circulation could = loss of a limb For the most part nurses don’t trim nails of diabetic clients. Refer to Podiatrist. For the most part nurses don’t trim nails of diabetic clients. Refer to Podiatrist.

Typical diabetic foot ulcer

Quick Quiz: 1. Give name of the very important anabolic hormone that builds up glucose and stores it as glycogen. 1. Give name of the very important anabolic hormone that builds up glucose and stores it as glycogen. 2. What is the usable form of sugar in the blood called? 3. What are the cells associated with insulin production called? 3. What are the cells associated with insulin production called? 4. What is the main problem (physiologically) that exists in people that are diabetic? 4. What is the main problem (physiologically) that exists in people that are diabetic?

Quick Quiz, cont. 5. In a normal person without diabetes, __________ ____________will result thus allowing high blood _________ to stimulate 5. In a normal person without diabetes, __________ ____________will result thus allowing high blood _________ to stimulate Insulin secretion. 6. Low blood sugar will stimulate what to be released? 7. Describe how someone would look/act if they were hyperglycemic

Quick Quiz, cont. 8. Describe someone who is hypoglycemic 8. Describe someone who is hypoglycemic 9. List 3 treatments/preventions for diabetes and label if they are for Type 1, 2 or both 10. What is the good news for diabetes?