Conditions Effecting the Endocrine System and PharmacotherapyPart One: Pancreas & DM Flashcards
Exam 2
The Endocrine function of Pancreas:
Islets of Langerhans
The pancreatic islets or islets of Langerhans are the regions of the pancreas that contain its endocrine (hormone-producing) cells
The Endocrine function of Pancreas:
What cells make up the Islets of Langerhans?
- Beta cells
- Alpha cells
The Endocrine function of Pancreas:
What do beta cells do?
Beta cells—insulin and amylin
secrete the hormone insulin in response to a high concentration of glucose in the blood.
The Endocrine function of Pancreas:
What do alpha cells do?
Secrete glucagon in response to low blood glucose levels
The Endocrine function of Pancreas:
What is glucagon?
antagonistic to insulin
The Endocrine function of Pancreas:
What do alpha cells do to glucose stores?
Mobilize glucose stores from liver
to brain/heart & used for energy production
The Endocrine function of Pancreas:
What are the hormones of the pancreas?
Amylin
GLP-1 glucagon-like peptide 1 Incretin hormone
The Endocrine function of Pancreas:
What is Amylin?
Peptide hormone co-secreted with insulin by beta cells
The Endocrine function of Pancreas:
What does amylin do?
Delays gastric emptying,
suppresses glucagon secretion,
decreasing postprandial glucose
Satiety,
reduces food intake,
works with insulin,
prevents hyperglycemia
The Endocrine function of Pancreas:
What does GLP-1 glucagon-like peptide 1 Incretin hormone do?
Slows gastric emptying, stimulates insulin release
Suppresses postprandial glucose
The Endocrine function of Pancreas:
Where is GLP-1 glucagon-like peptide 1 Incretin hormone produced? What does it respond to?
Produced in gut, responds to nutrients in the gut - carbs and fats.
The Endocrine function of Pancreas:
What does GLP-1 glucagon-like peptide 1 Incretin hormone act on?
Acts via the vagus nerve to regulate appetite control
Glucose metabolism & the role of insulin:
How does the pancreas act on in the liver?
The pancreas releases insulin which stimulates the synthesis of glycogen &
↑’d uptake
Fat synthesis
Glucose metabolism & the role of insulin”
How does the pancreas’ insulin act on the liver?
Gluceose trigger pancreas to release insulin.
Insulin causes other stuff
Insulin tells liver to uptake the glucose and turn the glucose into storage form (glycogen)
Glucose metabolism & the role of insulin:
When food consumed, what does the pancreas do?
Stimulates release of insulin into blood
Glucose metabolism & the role of insulin:
How does insulin act on the muscle?
↑’d uptake glucose & AAs, glycogen synthesis, protein synthesis (anabolic)
Glucose metabolism & the role of insulin:
What does insulin do to K?
Insulin also ↑ K+ uptake by cells
Glucose metabolism & the role of insulin:
What does insulin do to fat storing cells?
Insulin causes an increase in glucose uptake
Glucose metabolism & the role of insulin:
What is role of insulin on the muscle?
Insulin stimulates increased glucose uptake by skeletal muscle and activates glycogen synthase, protein synthesis
What does insulin do to fat cells?
When glucose levels are high, the pancreas secretes insulin, which signals fat cells to take in glucose.
Glucose metabolism & the role of insulin:
What does fat cells do to glucose they uptake?
Cells can then use the glucose for energy or convert it into fat for long-term storage.
Glucose metabolism & the role of insulin:
What is the goal for insulin?
Blood glucose level declines and stimulus for insulin release diminishes
In basic terms, what does insulin do?
What does glucagon do?
Insulin drives glucose into cells
Glucagon is for when glucose is gone
Metabolic Consequences of Insulin Deficiency :
What mode is your body in when there is an insulin deficiency?
Insulin deficiency puts the body into catabolic mode
Metabolic Consequences of Insulin Deficiency
In the absence of insulin, what 3 things get changed/converted?
Glycogen
Proteins
Fats
Metabolic Consequences of Insulin Deficiency:
In the absence of insulin, what happens with glycogen?
Glycogen –> converted into glucose
Metabolic Consequences of Insulin Deficiency:
In the absence of insulin, what happens with proteins?
Proteins –> degraded into amino acids
Metabolic Consequences of Insulin Deficiency:
In the absence of insulin, what happens with fats?
Fats –> converted to glycerol & free fatty acids
What does insulin deficiency promote?
Insulin deficiency promotes hyperglycemia
Insulin deficiency promotes hyperglycemia via what?
Increased glycogenolysis (breakdown of glycogen)
Increased gluconeogenesis (generation of new glucose)
Reduced glucose utilization
Metabolic Consequences of Insulin Deficiency :
What does Increased glycogenolysis (breakdown of glycogen) mean?
Breakdown of glycogen into free glucose
Metabolic Consequences of Insulin Deficiency :
What does Increased gluconeogenesis (generation of new glucose) mean?
Amino acids & fatty acids produced from metabolic breakdown of proteins & fats
Amino acids & fatty acids produced from metabolic breakdown of proteins & fats
Lead to what?
Fat breakdown –> weight loss
Metabolic Consequences of Insulin Deficiency :
Reduced glucose utilization leads to what?
Decreased cellular uptake of glucose
Decreased conversion of glucose to glycogen
Diabetes mellitus -what is it characterized by?
Characterized by hyperglycemia resulting from defects in insulin production, insulin action, or both.
Diabetes mellitus -what is Impaired insulin production or action results?
Impaired insulin production or action results in abnormal carbohydrate, protein, and fat metabolism because of the glucose transportation issue.
What is the primary disorder of carb metabolism manifested as?
Primary disorder of CHO metabolism manifested as high blood glucose levels from the body’s inability to produce or properly use insulin.
Glucose cannot be moved into cells & utilized.
What is Type 1 Diabetes:
↓’d insulin secretion by Beta cells of islets of Langerhans (Type 1)
What is Type 2 Diabetes:
insensitivity to insulin (Type 2).
Without insulin’s effects, what can or can’t happen?
Without insulin’s effects, glucose cannot be moved into cells. Insulin is needed to maintain life!!!
T1DM overview:
What is T1DM formally known as?
Child-onset DM & Insulin-dependent DM (IDDM)
T1DM overview:
When does it typically develop? What percent of the population is affected?
Typically develops during childhood or adolescence
5%-10% of the population
T1DM overview :
What does T1DM cause destruction of?
Destruction of pancreatic beta cells (autoimmune)
T1DM overview:
What does T1DM require?
Insulin supplementation!!!
T1DM overview:
What are predisposing factors to T1DM?
Genetics
Family hx
Any physical condition that destroys pancreatic beta cells
Abnormal immune response
Envi: drugs, foods, viruses
What genetics would be a predisposing factor to T1DM?
major histocompatibility complex (MHC)
people with variant of this have higher chance of developing T1DM?
How do major complications of T1DM occur?
Occur early
Often severe
Patho of T1DM:
What kind of reaction is it?
Autoimmune reaction
What happens in the autoimmune reaction of T1DM?
Islet cell autoantibodies destroy beta cells
Reduces normal pancreatic functioning by 80% to 90%
Patho of T1DM
What causes a lack of insulin in T1DM?
How long does this occur before symptoms to occur?
Destroyed beta cells cause lack of insulin
Can occur for months/years before symptoms of diabetes.
Patho of T1DM:
How would hyperglycemia occur in T1DM?
No glucose enters the cells resulting in hyperglycemia
What is altered in T1DM?
Metabolism of protein, fat, and carbohydrates is altered
Patho of T1DM:
What acts on the liver in T1DM? What does this lead to?
Glucagon from alpha cells acts in the liver –> glycogenolysis and gluconeogenesis
Patho of T1DM:
What does lack of insulin and excess of glucagon lead to?
lack of insulin & excess of glucagon –> hyperglycemia
Patho of T1DM:
Why does increased thirst occur in T1DM?
Osmotic glucose –> thirst
Patho of T1DM:
What is elevated glucose greater than?
Elevated glucose > renal threshold
Patho of T1DM:
What are symptoms of T1DM?
thirst
weight loss
excessive hunger
Patho of T1DM:
Why does weight loss occur in T1DM?
Inappro utilization of carbs–> weight loss
What leads to excessive hunger in T1DM?
Why does excess hunger occur?
Breakdown of nutritional stores –> excessive hunger because inefficient use of glucose
Patho of T1DM:
What does elevated glucose do to blood?
Elevated glucose makes blood hypertonic
Patho of T1DM:
What is the honeymoon phase?
a period after an initial type 1 diabetes diagnosis when the remaining insulin-producing beta cells in the pancreas are still functioning well.
at first, giving insulin injections rejuvenates beta cells. But then over time, beta cells lose ability and die or whatever.
T2DM: What is it formally known as?
Adult-onset/Non-insulin-independent DM
T2DM: When does it typically develop?
Typically develops in adulthood
What percent of people with diabetes have type 2?
90% to 95% of people with diabetes have type 2
What are the causes of Type II Diabetes?
Insulin resistance, genetics, envi
Decreased effectiveness of the cells’ insulin receptors
Insulin deficit (body may not be producing enough insulin)
What is still produced in T2DM that isn’t produced in T1DM?
Insulin still produced
In T2DM, insulin is still produced, but what is the issue with it?
Reduced binding to receptors
Reduced # of receptors
Reduced receptor responsiveness
What are predisposing factors to T2DM?
Age
Obesity
Race/ethnicity
Metabolic syndrome
Prediabetes
Diet – simple carbs, sat fats, red meat
Patho of T2DM: Occurs in what two ways?
Insulin resistance:
Pancreatic islet cells dysfunctional
Patho of T2DM:
In T2DM, what does insulin resistance mean?
Insulin resistance: Cellular insulin receptors less sensitive
Patho of T2DM:
What does Pancreatic islet dysfunction lead to?
Pancreatic islet cells dysfunctional –> decreased synthesis of insulin and rise of glucagon —> glucose synthesis in liver.
Patho of T2DM
What leads to hyperglycemia?
Liver synthesis of glucose increases when the pancreatic islet cells malfunction –> hyperglycemia
Patho of T2DM:
Inflammation
adipocyte cells & cytokines induce insulin resistance/cytotoxic to beta cells
Patho of T2DM
Obesity and Insulin resistance lead to what specifically?
Adipokines, FFAs, inflammation, mitochondrial dysfunction
Patho of T2DM:
What prevents clinical appearance of DM for many years?
Compensatory hyperinsulinemia prevents clinical appearance of DM for many years
Patho of T2DM:
What happens to alpha cells in response to glucose inhibition, what does this lead to?
Pancreatic alpha cells become less responsive to glucose inhibition –> increase in glucagon secretion –> increase in glucagon secretion –> hyperglycemia
Clinical Manifestations of Diabetes:
The classic signs (3Ps) are mostly present in what kind of diabetes?
Classic Signs (3Ps) (mostly in Type 1)
Clinical Manifestations of Diabetes:
What are the classic signs (3Ps):
Polyuria
Polydipsia
Polyphagia
Clinical Manifestations of Diabetes:
Polyuria- Why does this occur?
Glucose in urine exerts osmotic pressure in the filtrate –> a large volume of urine excreted.
Clinical Manifestations of Diabetes:
Polyuria- the large volume of urine excreted leads to what?
The large excretion results in a subsequent loss of fluid and electrolytes.
Clinical Manifestations of Diabetes:
Polydipsia:
Thirst from fluid loss through the large volume of urine produced and high blood glucose, since both draw water from the cells
Clinical Manifestations of Diabetes:
Polydipsia- what does it lead to?
Thirst from fluid loss through the large volume of urine produced and high blood glucose, since both draw water from the cells
leads to dehydration, increased thirst.
Clinical Manifestations of Diabetes:
Polyphagia
The cells in a person with diabetes lack nutrients, stimulating and increasing the person’s appetite.
Additional Clinical Manifestations: T1DM
What are they?
Flushed skin, fruity breath
Listless, lethargic
Unusual thirst, ↑UO
Skin dry
Hyperventilate
Elevated sugar
Drowsiness
Skin hot and dry: sugar high
Additional Clinical Manifestations: T1DM:
Why does hyperglycemia occur?
Insulin allows glucose access into cells.
Without insulin, there are increased blood glucose levels, since glucose cannot enter cells.
Additional Clinical Manifestations: T1DM:
Why does glucosuria occur?
When glucose builds up in the blood, excess glucose spills into the urine. This is because the level of glucose in the filtrate exceeds the capacity of the renal tubular transport limits for reabsorption.
Additional Clinical Manifestations: T1DM
Why does fatigue and lethargy occur?
Without glucose being able to enter the cells in the body, there is no energy for cells to function.
Additional Clinical Manifestations: T1DM
Why does weight loss occur?
Glucose-starved cells must use protein and fats for energy, so the person loses weight.
Additional Clinical Manifestations: T2DM
What are symptoms:
Nonspecific
Fatigue
Recurrent infections
Recurrent vaginal or candida infections
prolonged healing
visual changes
weight gain
Additional Clinical Manifestations: T2DM
Are nonspecific symptoms always present? Why or why not?
The classic signs (polyuria, polydipsia, polyphasia) of diabetes may or may not be observed.
The body still has some insulin that functions properly, although it may not be enough or efficient.
Additional Clinical Manifestations: T2DM:
Why would fatigue occur?
Insulin resistance does not allow glucose to enter the cell efficiently.
This means the cells do not get the energy they need, and the person becomes tired.
Additional Clinical Manifestations: T2DM:
Why would recurrent infections occur?
Increased glucose in the blood impairs the immune system because immune cells do not function as well in high glucose environments & some pathogens proliferate rapidly, suppressed immune response from chronic hyperglycemia
Additional Clinical Manifestations: T2DM:
Why would recurrent vaginal or candida infections occur?
Increased glucose is an excellent source for yeast and fungal growth.
Additional Clinical Manifestations: T2DM
Why would prolonged healing occur?
Increased glucose impairs and slows the healing of wounds.
Glycosolated hgb in RBCS impedes release of O2 to tissues
Additional Clinical Manifestations: T2DM
Prolonged healing: what would impede release of O2 into tissues?
Glycosolated hgb in RBCS impedes release of O2 to tissues
Additional Clinical Manifestations: T2DM:
Why would visual changes occur?
Increased glucose damages the small vessels in the eye, leading to vision changes.
Additional Clinical Manifestations: T2DM:
What leads to weight gain?
Increased weight or obesity predispose an individual to type 2 diabetes.
Chronic complications of DM:
What parts of the body does DM effect?
Retina, kidney, RBCs, nerves, & blood vessels cells
Chronic complications of DM:
Part of the body that DM effects, (Retina, kidney, RBCs, nerves, & blood vessels cells) why do effects occur?
Glucose in increased amounts in these cells that do not require insulin
Chronic complications of DM
What does glucose do to (Retina, kidney, RBCs, nerves, & blood vessels cells)?
What is glucose converted to?
Glucose readily diffuses in excess into these cells & is converted to sorbitol (an alcohol) which is osmotically active (pulls in H2O)
Chronic complications of DM
When glucose readily diffuses in excess into (Retina, kidney, RBCs, nerves, & blood vessels) cells, what does it do to the cells?
Alters cell function by direct effect & effect of excess intracellular H2O
Chronic complications of DM:
What accumulates in toxic levels? What does it contribute to?
More sorbitol & lower levels of glutathione accumulate to toxic levels
Contribute to chronic tissue damage
Chronic complications of DM:
How does hyperglycemia effect other cells?
Hyperglycemia leads to attachment of glucose to proteins, lipids, & nucleic acids (glycation)
Chronic complications of DM:
What does glycation lead to?
leads to advanced glycation end products (AGEs)
Chronic complications of DM
What do AGEs cause?
Interfere with many crucial cellular processes
Microvascular damage:
MACROVASCULAR damage:
Chronic complications of DM
Microvascular damage:
capillaries, retinopathies, nephropathies, neuropathies
Chronic complications of DM
MACROVASCULAR damage:
MACROVASCULAR damage: larger vessels, CAD, PVD, Cerebral VD
Chronic complications of DM:
When sugar bombards basement membrane of small BVs, capillaries
When sugar bombards basement membrane of small BVs, capillaries it leads to structural defects – leakier, thicker
Chronic complications of DM:
What would happen to oxygen delivery, why? What happens to oxygen in the tissues?
- Decreased O2 delivery due to glycosylated hgb (HgbA1c) – increases its affinity for O2 which leads to less released to tissues
Chronic complications of DM:
What is not catalyzed due to a build up of glucose? What does this lead to?
- Fibrin not catalyzed with attached glucose, –> builds up & blocks vessels.
Chronic complications of DM:
Fibrin not catalyzed with attached glucose, –> builds up & blocks vessels.
What happens to platelets?
↑’d platelet aggregation, initiation of clotting process
Chronic complications of DM:
What does DM cause in the intima of blood vessels?
- Collagen – attached glucose makes intima of BVs “sticky” – lipoproteins collect
Chronic complications of DM:
What happens with Fat-protein (cholesterol and TGs) when glucose is attached?
Fat-protein (cholesterol & TGs) – when glucose attached, abnormally deposited in bv walls
Chronic complications of DM:
What happens with TGs?
Increased production of TGs by liver & low HDL
Chronic complications of DM:
How would atherosclerosis occur?
Bad cholesterol is loaded down with glucose & is abnormally deposited –> atherosclerosis
Degenerative Changes Related to Diabetes include:
Microangiopathy
Macroangiopathy
Neuropathy