DM Flashcards
insulin effect
- Increase uptake of glucose, translocate GLUT 4
- GLUT 4: muscle, adipose tissue
- GLUT2: kidney, liver, pancreatic b cell
- GLUT3: neurons
- Glycogenesis
- Glucose –> glycogen (storage in liver muscle)
- Also causes:
○ lipogenesis (FFA–> TG in adipose tissue)
Proteogenesis (aa –> proteins in muscle)
glucagon effect
- Glycogenolysis
- Glycogen –> glucose
- Lipolysis
- TGL –> FFA –> glycerol + ketones
- Proteolysis
- Protein –> aa
- Gluconeogenesis
- Aa –> glucose
Glycerol –> glucose
- Aa –> glucose
DM acute consequences
*Polyuria (excess urine production)
*Polydipsia (extreme thirst)
1) Excess BGL & urine
2) Osmotic diuresis
3) More urine produced
4) Dehydration
a) Decr blood vol –> peripheral circ failure –> renal failure –> death
b) Polydipsia –> cell shrink –> nervous system malfunction
*Polyphagia (appetite)
1) Incr glucose uptake
2) But still poor intake of glucose intracellularly
*Ketosis – rapid breathing
1) Use up other sources for energy
2) Decr TG synthesis & Incr lipolysis
3) Incr blood FA
4) Alternative energy source
5) Ketosis –> metabolic acidosis
a) Incr ventilation
b) Diabetic coma
i) Death (acidosis depress brain)
**fruity breath [acetone as by-product of fat metabolism]
*death
*weightloss
1) Decr aa uptake by cells + incr prot degradation
2) Muscle waste –> weight loss
3) Incr blood aa –> incr gluconeogenesis
4) Aggravates hyperglycemia (body has glucose but cannot use)
Degenerative blood vessels
□ Microvascular: retinopathy, nerve damage, kidney failure
□ Macrovascular: stroke, heart attack, reduce blood circ
Degenerative blood vessels
□ Microvascular: retinopathy, nerve damage, kidney failure
□ Macrovascular: stroke, heart attack, reduce blood circ
sx diabetes
Symptoms:
1) Tired
2) Weight loss
3) Slow wound healing
4) Sexual problems
5) Vaginal infections
6) Numb, tingling in feet
7) Blurry vision
8) Polydipsia,
9) polyphagia, polyuria
Incretins
Grp of metabolic hormones: released after eating
GIP (DPP4i)
GLP-1 (GLP1 Receptor agonist)
function of incretins
Augment secretory insulin released from pancreatic B cells of islets of Langerhans
Glucose-dependent manner – only when hyperglycemia
1) Gastric emptying in stomach
2) Glucose dependent insulin biosynthesis and secretion
i. Decr glucagon
ii. Improve b-cell function
3) Decr food intake (brain signal)
i. NV (common ADR)
Glucose-dependent insulinotropic polypeptide (GIP)
a. Insulin secretion
b. Expansion of pancreatic B cell
Glucagon-like peptide 1 (GLP-1)
a. Satiety
b. Gastric emptying decr
- Decr weight gain
METFORMIN MOA
- Incr glucose uptake into tissues
- Inhibit gluconeogenesis in liver
* Incr AMP-activated protein kinase - Enhance tissue sensitivity to insulin
* Uptake more glucose - Useful for obese pts
Weight loss and improve lipid levels
function of metformin
- Does not cause hyperinsulinemia
- No hypoglycemia
- Weight loss
- T2DM
- Alone/ other oral hypoglycemic agents
PK of metformins
A: PO, (duration 8-12hr)
D: rapidly distributed, minimal plasma protein binding
(T1/2 ~ 3hr)
M: NA
E: excreted unchanged in urine
- avoid in pt w/ renal insuff
- titrate
ADR of metformin
- Anorexia (LOA –> weight loss)
- GI disturbances
- Diarrhea, vomit indigestion, weight loss
- Take with/ after meal
- risk of Vit B12 def
- Malabsorption, more in LDC
CI of metformin
- Renal problems
- Lactic acidosis (hepatic, CVS problem)
Sulphonylurea MOA
- Glipizide
- Insulin secretagogues (2nd gen)
- Pancreatic b cells secrete insulin
1) SU bind to SU receptor proteins (subunit of K ATP channels)
2) Drug binding inhibits K ATP channel mediated K+ efflux
3) Depolarisation, Ca2+ influx
4) Trigger Ca dependent exocytosis of insulin granules
- from pancreatic B cells
glipizide function
Lowers BGL acutely
* Activate release of insulin from pancreas
* Depends on functioning B cells in pancreas islets
K ATP channel:
b cell ATP-sensitive K channel
- major role in control B cell mem potential
Glipizide: 2nd gen lower risk of hypoglycemia than other SU
PK of glipizide
A: PO
- F>95%, delayed with food intake
- (onset 0.5hr)
- (duration 12-24hr)
D: binds extensively 99% to plasma proteins (albumin)
(T1/2 ~ 4hr)
M: liver (90%)
E: <10% excreted unchanged in urine, feces
Metabolites: urine, feces
- avoid in renal insuff
- titrate
glipizide metabolism
- P1: hydroxylation
- liver disease, titrate
ADR of glipizide
- Hypoglycemia
- Elderly (poorer liver, kidney function)
*Weight gain
Sitagliptin
DPP-4i MOA
1) Binds, inhibit DPP4
2) Decr enzymatic degradation of GLP-1
3) Prolong action of endogenous insulin (by body)
* Stimulate B cells Release insulin (as if there is presence of glucose)
4) Suppress a- cell mediated glucagon release & hepatic glucose production
* Decr BGL (less glucagon)
DPP-4i function
- Incretin-based therapy
- Dipeptidyl peptidase-1 inhibitor
- less break down incretin
Mono: when MET not suitable/ no response
Combi: MET/ SU/ TZD + DPP4i
Triple:
Insulin+MET/
MET+SU/
MET+TZD
DPP4i PK
A: PO
- F ~ 87%
D: (T1/2 ~ 10-12hr)
M: low liver metabolism
E: 80% excreted in urine
- avoid in renal insuff
- titrate
DPP4i ADR
- GI disturbances
- Flu-like symptoms
- Headache, running nose, sore throat
- Skin reactions