Introduction to diabetes mellitus Flashcards
How does insulin act
Decreases hepatic glucose output - decreases gluconeogensis
Increase muscle uptake of glucose
Decrease proteolysis
Decreases lipolysis
Decrease ketogenesis
Clinical Relevance of glucose
Type 1 diabetes
Hypoglycaemia
Insulin Resistance
Type 2 diabetes
What is the GLUT-4 transporters
Common in myocytes (muscle) and adipocytes (Fat)
Highly insulin-responsive
Recruited and enhanced by insulin
Increase glucose uptake
Hydrophilic inside and hydrophobic outside
Effects of insulin on cell metabolism
Insulin inhibits protein breakdown
Converts amino acids into protein - GH, IGF-1
Cortisol helps gluconeogenic aminoa cids transfer from myocyte to liver
What happens in gluconeogensis
AA taken up by the liver - enhanced by glucagon
Insulin encourages AA to protein
Insulin gluconeogenesis
Glucagon and Cortisol encourages protein to AA and gluconeogensis
How long to the fuel stores last
Carbs - 16hrs
Protein - 15 days
Fat - 30 to 40 days
How are triglycerides broken down
Lipoprotein lipase break them down
Not esterified fatty acid
Insulin activates this enzyme
Glucose can also be taken up by adipocytes by GLUT-4
Insulin also converts gly and NEFA into triglycerides
Insulin inhibits triglycerides
Where is insulin released
Hepatic protal circulation
What does glycerol do in the liver
During fed state, it converts to triglycerides
It can be converted to glucose
What is the cerebral energy requirement of the brain
Glucose (preferred
Keton bodies
No NEFA
WHat does ketones bodies to in liver
NEFA enter the liver
Insulin inhibits conversion of fatty acyl-coA into ketone bodies
What does glucose does in the liver
Hepatic glycogenolysis
Generation of glucose from stored glycogen in the liver
What can muslce cells utilise as energy
NEFA
Glucose
Can muscle cells release glucose into circulation
No
What hormones and pathways happen in fasted state
Low insulin-to-glucagon ratio
Glucose is low (normal range 3.0-5.5mmol/l)
Increase in NEFA - breaking down lipids and fats
Increase then decrease in amino acids
Proteolysis
Lipolysis
HGO
Ketogenesis production
Muscles will use lipids and brain will use glucose adn ketons
What hormones and pathways happen in the fed state
High insulin release flowed by slower insulin release
Increase in glycogen
Stop HGO
Decrease gluconeogensis
Increase protein synthesis
Decrease proteolysis
Lipogenesis
How do you diagnose diabetes mellitus
Fasting glucose >7.0mmol/L
Randome glucose >11.1mmol/L
Oral glucose tolerance test
HbA1c (>48mmol/mol)
Need 2 positive test or 1 positive test and symptoms
What is the pathophysiology in type 1 diabetes
Autoimmune condition
Absolute insulin deficiency
Diabetic ketoacidosis
What are the presentations of T1DM
Weight loss - protein break down
Hyperglycaemia
Glycosuria - polyuria, polydipsia, nocturia
Ketones in blood and urine
What is the useful diagnostic test of T1DM
Antibodies: GAD, IA2
Low C peptide
Presence of ketones
What is insulin induced hypoglycaemia
Where you take too much insulin
What is the couterregulatory response to hypoglycaemia
Increae glucagon, catechoalmines, cortisol and growth hormone
Increase HGO and glycogenolysis, glyconeogensis, lipolysis
Why is imparied awareness of hypoglycaemia bad
Reduce awareness of hypoglycaemia
Due to threshold of glucose being reset
Recurrent hypoglycaenia
Symptoms of hypoglycaemia
Sweating, pallor, palpitations, shaking
Slurred speech, Poor vision, confusion, seizures, loss of consciousness
What is severe hypoglycaemia
Episode where a person needs third party assistance
What is the pathophysiology in type 2 diabetes
Enough insulin to suppress breakdown of protein and ketogenesis
What happens during insulin resistance
P13K-Akt pathway because resistance however MAPK apthway still works
Increase insulin production results in increase growth and proliferation - growth of arteriols which lead to high blood pressure
What are the consequences of insulin resistance
Derangement of lipid
Hyeprtension
Increase weight
Inflammatory states
Decrease energy expenditure
What is the presentaiton of T2DM
Hyperglycaemia
Overweight
Less osmotic symptoms
Dyslipidaemia
Insulin resistance
What are the risk factors of T2DM
Age
Increase BMI
Ethnicity
Family
Inactivity
PCOS
What are diabetes complications
What treatment are there for diabetes
Healthy eating or diet control - Reduce calories in fat and refined carbohydrates, sodium, increase fibre and complex carbs
What is the management of type 1 diabetes
Type 1 - exogenous insulin (basal-bolus regime, long acting once or twice a day and quick acting right before meal)
Self-monitoring of glucose
Technology
Education
What is the management of type 2 diabetes
Diet
Oral medication
Education
May need insulin later
Long term coseuqences of diabetes
Retinopathy
Neuropathy
Nephropathy
Cardiovascular disease
