Diabetes Mellitus Flashcards
How does normal carbohydrate metabolism occur
Eat food, broken down, turned into glucose, blood sugar goes up, pancreas releases insulin, insulin binds to receptors, signals transduction of glucose into cell, glucose transporters open up doorways to allow glucose into the cell
What happens to glucose without insulin
Stays in the blood cause there is nothing to signal it into the cell.
T1DM definition
Complete absence of insulin from the pancreas
What is glucagon
Hormone that is triggered when glycogen is needed
What is glycogen
Extra glucose stored in the liver
How are beta cells involved in T1DM
Beta cells are destroyed causing the inability to produce insulin
What are the 2 causes of T1DM
- Immune mediated (immune system attacks beta cells causing inflammatory response
- Idiopathic (we have no idea)
What is a FBG test
Fasting blood glucose: 8 hours of no caloric intake
What is an OGTT test
Oral Glucose Tolerance Test: yucky orange drink with tons of sugar to see how body handles excess sugar
What is DKA
Diabetic ketoacidosis is a state of metabolic acidosis directly caused by absolute or relative insulin deficiency. Most common in T1, but can be seen in T2.
What causes DKA
Trauma, surgeries, illness (when we don’t treat their imbalances or aren’t treating with insulin)
Ketonemia
Increased ketones in the blood
Ketones
Alternative form of energy made by the liver when body is low on sugar. Using fat for instead of glucose for energy. Created from the breakdown of fats.
What are the 7 I’s of DKA
Infection, Ischemia, Intoxication, Intolerance, iatrogenic, initial presentation, impregnation
What are some counter regulatory hormones in DKA
Epinephrine, glucagon, cortisol, growth hormone (all increase glucose production and make the situation worse)
How does DKA cause hypovolemia, acid base imbalance, and electrolyte imbalance
Hypovolemia: increased plasma concentration of glucose triggers body to pee more, therefore depleting volume. AB imbalance: ketones cause the blood to become acidic. Electrolyte imbalances: due to excessive peeing lots of electrolytes are lost.
Where does acetone come into play in DKA
Type of ketone/acid that builds up in DKA and causes the fruity breath smell.
Why might Kussmaul breathing occur in DKA
Because of the metabolic acidosis the respiratory system tries to compensate by getting rid of the easy acid (CO2) by breathing it off quickly
Why is serum bicarbonate low in DKA
The abundance of ketones (acids) dissociate and hydrogen ions bind to bicarbonate, causing decreased serum bicarbonate.
Why is insulin used to treat the acidosis in DKA and not bicarbonate
Because we are trying to treat the cause (hyperglycemia) and not the presentation (metabolic acidosis)
What are some causes of T2DM
Non-modifiable: genetics
Modifiable: diet, excessive, lifestyle, metabolic syndrome
What are the diagnostic criteria for metabolic syndrome
Adipose tissue at the waste, HTN, High triglycerides, low HDL, High LDL, high fasting glucose (need 3 out of the 5)
What are the 2 mechanisms of T2DM
Insulin resistance: many organs contribute. Suboptimal response to insulin from insulin sensitive tissues such as the liver, muscles, and adipose tissue
Decreased beta cell mass and function
What is amylin
Hormone that increases satiety and suppresses glucagon release but increases production leads to amylin deposits in beta cells that leads to their destruction, worsening insulin deficiency
What is Ghrelin
Hormone that regulates food intake, energy balance, and hormonal secretion and insulin resistance leads to decreased levels of ghrelin
How does ozempic work
Increases amylin, causes nausea and vomiting, can cause non-diabetics to slip into hypoglycemia
What are the 2 ways insulin acts on adipose tissue
- Stimulating glucose uptake and triglyceride synthesis
- Suppressing triglyceride hydrolysis
How does increased abdominal tissue cause insulin resistance
Increased adipose tissue causes release of inflammatory cytokines which induces insulin resistance and are cytotoxic to beta cells
How does decreased muscle cells and increased fat cells cause hyperglycemia
Glucose isn’t being taken up by cells causing fatigue
How does the pancreas contribute to hyperglycemia
Alpha cells release glucagon
How does the liver contribute to hyperglycemia
Increased gluconeogenesis and glucogenolysis
How do the kidneys contribute to hyperglycemia
Reabsorb glucose through sodium glucose transporter until threshold exceeded causing glycosuria
How does an environment of insulin resistance cause a decrease in beta cell mass and function
Beta cells attempt to maintain normal BG levels. Hyperinsulinemia occurs due to increased demand for insulin. Beta cell hypertrophy and develop hyperplasia to increase insulin supply. Increased amylin deposits affect beta cell functioning. Beta cell exhaustion leads to hypoplasia and hypotrophy.
