LMP301 Lecture 12: Diabetes Flashcards
Diabetes
Diabetes is a(n) ___ disorder
endocrine
Effects of insulin binding to receptor
- Translocation of GLUT-4 to membrane
- Glycogen synthesis
- Glycolysis
- FA synthesis
Glucose -> glycogen through what process?
oxidation
In the fed state, liver removes ___% of glucose load
70
Excess glucose is…
- converted to VLDL
- stored in adipose tissue
What happens in the fasting state?
- glycogen breakdown
- gluconeogenesis
In gluconeogenesis, what are the starting materials?
- glycerol
- lactate
- pyruvate
- AA
What can increase blood glucose?
- glucagon
- GH
- Adrenaline
- Cortisol
GH is made in the…
a. pituitary
Cortisol is made in the…
adrenal gland
Synthesis / cleaving of insulin
pre-proinsulin -> proinsulin -> insulin
Composition of insulin
2 AA chains connected by disulfide links
Insulin inhibits…
- lipid ketosis
- somatostatin
- glucagon
Insulin promotes…
- glucose uptake
- K+ and PO4^3- uptake
- synthesis of protein
Besides gestational, type I, and type II diabetes, what other causes might there be?
- genetic diseases cause defective B-cell
- genetic diseases infect pancreas / other endocrine organs
e.g. hematochromatosis, Cushings’, pheochromocytoma
Complications of DM
- microangiopathy
- retinopathy
- nephropathy
- neuropathy
- macroangiopathy
microangiopathy
small vessels being destroyed due to high level of glucose
neuropathy
damage to PNS
macroangiopathy
Diseases in large vessels due to high blood glucose
Diagnosis for DM.
What is used to confirm diabetes?
FBG >= 7
PG >= 11.1
OGTT >= 11.1
FBG or OGTT must surpass limit (just one)
FPG
fasting plasma glucose
PG
random plasma glucose
If testing for PG, what must be noted?
PG >= 11.1, but they must also display symptoms of
- Polydipsia
- Polyuria
- Weight loss
OGTT
oral glucose tolerance test
- give 75 g of glucose and measure PG 2h later
- repeat on different day
- only use when absolutely have to (ambiguous case)
What are the grey zones of diabetes?
- IFG
- IGT
- IFG and IGT
IFG
impaired fasting glucose
- FPG is higher than normal, but >= 7
IGT
impaired glucose tolerance
- normal FPG
- OGTT is higher than normal, but not >=11.1
People (at risk for) diabetes should be screened for…
- heart disease
- hypertension
- dslipidemia
3 ways to monitor DM
- self-monitor of blood glucose / point-of-care testing
- microalbuminuria
- monitor mean glycemia
What is used for self-monitor of blood glucose?
personal glucometers, which need whole blood sample
microalbuminuria is an indicator of…
Nephropathy
microalbuminuria
small amount of albumin found in the urine
_____ = mean glycemia over long term
glycated hemoglobin (HbA_1c)
What is an advantage of monitoring mean glycemia
See how patient has behaved over the past 3 months
Many proteins become ___ due to hyperglycemia
glycated
Structure of HbA_1c
glucose attached (non-enzymatically) to valine (at N term of HbA)
HbA1c has the ___ concentration & lifespan as RBC, which is…
same
120 days
HbA1c should be monitored every…
3 months
Treatment target for HbA1c
=< 0.07
Treatment target for mean plasma glucose
=< 9.5
What parmacological management of diabetes is there?
antihyperglycemic agents can be used
antihyperglycemic agents can be used to…
- increase insulin sensitivity
- increase insulin secretion
- slow rate of carb absorption
which drug: increase insulin sensitivity
metformin
which drug: increase insulin secretion
sulfonylureas
which drug: slow rate of carb absorption
a-glucosidase
Insulin should be used to treat diabetes when…
no other options work
Usually given as insulin + another drug (do not want to be solely dependent on insulin)
Complications of diabetes
- Diabetic ketoacidosis
- Hyperosomolar non-ketotic coma
- hypoglycemia
symptoms of diabetic ketoacidosis
- dehydration
- vomiting
- hyperventilation
Why do some diabetics experience ketoacidosis?
Can’t use glucose, so use fat (ketones) as fuel for brain
What hormones tend to be secreted in response to diabetic stress?
- catecholamines
- cortisol
- GH
(all agonist to insulin)
Why do some diabetics experience dehydration?
- ketoacidosis causes vomiting
2. hyperglycemia causes glucosuria & osmotic diuresis
How to manage diabetic ketoacidosis?
- ASAP: give insulin and fluids
- Give K+ to balance out effects of insulin
- bicarb: neutralize acidosis
Effect of insulin on K+
Insulin makes cells take up K+
Who gets diabetic ketoacidosis?
type I
Who gets hyperosmolar non-ketotic coma?
type I
symptoms of hyperosmolar non-ketotic coma
- hyperglycemia
- osmotic diuresis / glucosuria
- dehydration
- unconscious
hyperosmolar non-ketotic coma is a ___ disorder
chronic (develops over time)
diabetic ketoacidosis is an ____ disorder
acute (happens very rapidly)
why do people with hyperosmolar non-ketotic coma not have ketosis symptoms, but have hyperglycemia?
Residual insulin in body can prevent ketoacidosis symptoms, but not enough to prevent hyperglycemia
Treatment of hyperosmolar non-ketotic coma
Show rehydration and insulin
Of the 3 complications of diabetes, which is the most severe?
hypoglycemia is a clinical emergency
symptoms of hypoglycemia
- sweating
- shaking
- tachycardia
- weak
- nausea
- confusion
- coma
biochemical diagnosis of hypoglycemia
<2.2
Treatment of hypoglycemia
give glucose
causes of hypoglycemia for diabetics
- excess insulin
- not enough carb intake
- exercise
Risk factors for developing diabetes
- hypertension
- dyslipidemia / overweight / abdominal obesity
- other diseases (schizophrenia, PCOS, vascular)
- family history
- IGT or IFG
- gestational DM or macrosomic infant
- ethnicity
- metabolic syndrome
Which ethnic groups are at higher risk for diabetes?
- aboriginals
- hispanics
- asians
- s. asians
- africans
Metabolic syndrome: 3 of the following must be met…
- waist circumference
- TG
- HDL
- BP
- FBG
