Endocrinology- Exam 3- Part 3- Pancreas (copy)

What cells are responsible for glucagon synthesis?

alpha cells of pancreas

What type of hormone is glucagon?

peptide

what is the antagonist to insulin?

glucagon

What inhibits glucagon?

What stimulates glucagon?

-hyperglycemia (high glucose), somatostatin

- hypoglycemia (low glucose)

What physiologic mechanism does glucagon use?

adenylyl cyclase mechanism (cAMP second messenger)

What are the main target tissues of glucagon?

liver, adipose tissue

(muscle does not like to share glucose)

What is the goal of glucagon when secreted?

increase blood glucose levels

If glucagon acts on the liver, what does it stimulate to increase blood glucose levels? TQ

-glycogenolysis

-gluconeogenesis

If glucagon acts on adipose tissue, what does it stimulate to increase blood glucose levels? TQ

LIPOLYSIS!

-activates hormone sensitive lipase (HSL) to break down triglycerides into FA and diacylglycerol

-FAs then undergo beta-oxidation if in the liver, otherwise used for fuel for tissues

-glycerol goes to the liver for gluconeogenesis

If too many FAs are in the liver after hormone sensitive lipase breaks TGs into FAs and glycerol, what can occur?

-too much beta-oxidation of FAs that can lead to excess conversion into ketone bodies--> KETOGENESIS--> KETOACIDOSIS

T/F: There is a balance between insulin inhibiting hormone sensitive lipase and glucagon activating it that maintain FA/glucose levels. If this balance is thrown off (ex: person can't make insulin) this can cause many problems.

TRUE

What is ketoacidosis? TQ (understand this)

high blood sugar, inadequate amount of insulin. Cells are burning fat for energy (ketones). As the cells burn more fat, acid levels in the body begin to increase to dangerous levels (acidosis)

What type of hormone is glucagon-like peptide-1 (GLP-1)?

polypeptide hormone

t/f: glucagon-like peptide 1 (GLP-1) acts similarly to glucagon and has the same taget tissues.

FALSE; looks like glucagon, does not act like glucagon. Acts like insulin

What is the role of GLP-1 when released?

-increases the release of insulin form the pancreas (B-cells) and reduces the release of glucagon

-increases satiety (feeling of fullness)

Where are receptors for GLP-1 in the body? (8)

-brain

-pancreas

-liver

-kidney

-heart

-stomach

-muscle

-bone

What is the main stimulator of GLP-1?

Food (eating)

what inhibits GLP-1?

somatostatin

What enzyme breaks down GLP-1?

-dipeptidyl peptidase-4 (DPP-4)

If after eating a large meal, you still have an immense hunger feeling, what may you potentially have a deficiency in?

GLP-1 (aids in satiety)

What are 4 main drugs that use GLP-1 to aid in diabetic patients and obesity problem? (probably don't need to know this)

Ozempic

Rybelsus

Wegovy

zepbound

What does STEP stand for?

Semaglutide Treatment Effect in people with obesity

T/F: STEP does show majority of users lose weight, but the adverse effects of the treatment are a big concern.

TRUE

What are the adverse effects of STEP?

-Nausea

-Diarrhea

-Vomiting

-Constipation

(GI problems)

What is the physiological half-life of GLP-1?

what is the pharmaceutical half-life of GLP-1?

-1-2 minutes

-up to 7 day half-life

What concerns occur with the excessive half-life of GLP-1 found in weight loss medications such as Ozempic?

-Decrease Lean muscle mass (sarcopenia)

-Increased Sympathetic Tone (HR)

-Decreased nutrition due to patients not eating

What is the most frequently seen pancreatic neuroendocrine tumor?

What does this tumor cause excess secretion of?

What does this lead to?

Insulinoma; insulin; hypoglycemia etc.

Which hormone producing tumor of the pancreas is rare and may produce symptoms of diabetes?

What is secreted in excess?

What does this lead to?

Glucagonomas; glucagon; catabolic (breakdown) effect on fat and muscle

What is the most common disease resulting from impaired pancreatic insulin release, resulting in hyperglycemia?

Diabetes Mellitus

Which form of Diabetes Mellitus is autoimmune, present in 5% of cases and is diagnosed by teenage years?

What happens in this form?

-Type 1 Diabetes mellitus

-beta cells of the pancreas are destroyed, leading to decreased insulin production --> decreased regulation blood glucose

What is the AKA for Type 1 DM?

Insulin dependent diabetes

(previously known as juvenile diabetes)

Which form of Diabetes Mellitus is autoimmune and is diagnosed around age 35 or older?

Type 1.5 Diabetes mellitus (latent autoimmune diabetes LADA)

Which form of diabetes shows features of both Type 1 (autoimmune activity) and Type 2 ( insulin-resistant) Diabetes and is typically diagnosed in adults?

Type 1.5 Diabetes mellitus (latent autoimmune diabetes LADA)

What is the most common form of diabetes (90+%)

Type II diabetes mellitus

What form of diabetes mellitus (DM) develops when the body becomes insulin resistant and/or is unable to produce enough insulin needed to control blood pressure?

Type II DM

What are the main symptoms of Type II DM?

-Excessive thirst

-frequent urination

-increased hunger

-tiredness

-loss of muscle mass gradually

What is a large risk factor (80%) to developing type II DM?

Obesity

What are the treatment options for Type II DM?

-Lifestyle changes (diet and exercise)

-Metformin, helps body respond better to insulin

(decrease in B12)

What does MODY stand for?

Mature onset of diabetes of the young

What is a rare genetic form of diabetes caused by mutation of the genes that affect insulin production/action?

MODY

Which form of diabetes is primarily caused by malnutrition and/or infections and/or genetic predispositions?

Type 5 DM

What populations are most affected by Type 5 DM?

those with limited access to proper nutrition/healthcare :(

What is prediabetes?

Term used to describe condition where glucose levels are higher than normal, but not high enough to be classified as diabetes. Increased risk of type 2 diabetes

What are the criteria used to diagnose metabolic syndrome?

1. Abdominal Obesity

2. Elevated TG levls in blood

3. Reduced levels of HDL cholesterol

4. High BP

5. Abnormal fasting glucose or previously dx diabetes

How many criteria need to be met to diagnose a patient with metabolic syndrome? TQ

3/5***

What is the normal (fasted) blood glucose range? TQ

what is the prediabetic blood glucose range? TQ

What is the diabetic blood glucose range?

TQ

normal: 70-100 mg/dL

prediabetic: 100-125 mg/dL

diabetic: 126 mg/dL and UP!

(below 70 is too low-->dizzy, blurred vision etc.)

After running a Hemoglobin A1C test on a patient, what range would the patient be in if that the patient is prediabetic?

What is a normal range of A1C?**

prediabetic: 5.7%-6.4%

normal: <5.7%

What is the range for prediabetic fasting glucose test? ** tq

100-125 mg/dL

What is the range for a prediabetic glucose tolerance test? **

Anything over this range is what?

140-199 mg/dL

diabetic

What are the clinical presentations of DM? 100% TQ

-Polyuria (glucose in urine pulls more water to it)

-Polydipsia (very thirsty)

-Polyphagia (increased hunger, due to increased lipolysis and proteolysis bc glucose can't be used as fuel in cells)

What are some main DM complications discussed in lecture? TQs

-Atherosclerosis

-Nephropathy (kidney failure)

-increased risk of Coronary artery disease

-Retinopathy

-Cataracts

-Neuropathy

-Demyelination of Schwann cells

and more...

What happens in the adipocyte with an insulin deficiency?

hormone sensitive lipase becomes very active and releases large quantities of FA and TGs into the blood

(FFAs become main energy source since glucose isn't going into cells)

insulin deficiency caused increased _________ _________ in the blood, which are converted to what?

fatty acids--> converted to phospholipids and cholesterol

(which then get converted to lipoproteins)

High cholesterol seen in diabetic patients promotes what?

atherosclerosis

T/F: Increased ketone bodies and ketoacidosis can occur due to insulin deficiency in diabetics.

TRUE

What is a measurement of the average level of blood sugar of a patient over the past 60-90 days and measures specifically how much glucose is bound to hemoglobin? TQ

Hemoglobin A1c (HbA1c)

T/F: Conditions can alter a hemoglobin A1c test that can cause false highs and false lows.

TRUE

What is the treatment for Type i DM?

Insulin (injections/pump)

What is the treatment for prediabetes and type II DM?

Exercise, Diet and medication (metformin)

What is the effect of a Diabetic patient that takes too much insulin?

How do you treat this?

-Shaking, sweating, increased HR, confusion, convulsions, seizures

-Quick sugar consumption

How does Diabetic ketoacidosis develop?

(EMERGENCY)

lack of insulin causes break down of protein and fat for fuel, producing ketones that accumulate.

Ketones drop pH and can lead to acidic conditions that can damage tissues/brain

What is the diabetic emergency condition when blood sugar levels get dangerously high (>600mg/dL)?

Hyperglycemic Hyperosmolar Syndrome (HHS)

How does a diabetic coma develop?

it's the outcome of dangerously high or low blood sugar