Diabetes Mellutis Flashcards
Where is GLUT4 commonly found
Myocytes and adipocytes
Highly insulin responsive
Lies in vesicles
Recruited and enhanced by insulin
Look at the diagrams on the effects of insulin on cell metabolism and gluconeogenesis
Effects of insulin on cell metabolism and gluconeogenesis
What runs out first as a fuel
Carbohydrates followed by protein and fat
What enzymes break down triglycerides
Lipoprotein lipas which breaks down triglycerides into NEFA and glycerol
Triglycerides are too big so unless broken down they would not be able to be taken up by adipocytes
Circulation adaptations that allow increased speed of digestion etc
From aorta you have an hepatoaorta circulation which allows rapid digestion in gut which then flows to liver so insulin is released quickly into the hepatoporto circulation and allows quick effects
Brain and cerebral energy requirement
Brain can use glucose and ketone bodies but the brains inability to utilise fatty acids as a fuel makes it unique among body tissue
Diagnosis of Diabetes Mellitus
Fasting state greater than 7 mmol/L
Random glucose >11.1 mmol/L
Oral glucose tolerance test ;
Fasting glucose
75g glucose load
2 hour glucose
HbA1c ( >48mmol/mol)
A diagnosis required 2 positive tests or 1 positive test and symptoms
Presentation of Type 1 diabetes
Weight loss due to protein breakdown
Hyperglycaemia
Glucosuria with osmotic symptoms ( polyuria, no Turk and polydipsia )
Ketones in blood and urine
Can cause diabetic ketoacidosis
Useful diagnostic tests for T1D
Antibodies ; GAD, IA2 and ZNT8
C peptide
Presence of ketones
Counter-regulatory response to hypoglycaemia
Increased glucagon
Increased catecholamines
Increased cortisol
Increased growth hormone
These all increase HGO with glycogenolysis and gluconeogenesis
Increased lipolysis
Impaired awareness of hypoglycaemia
Reduced ability to recognise symptoms of hypoglycaemia
Due to loss of counter regulatory response
Recurrent hypoglycaemia
Body gets used to having these episodes and so the threshold for which counterregulatory system kicks in falls below . So previously may have come in at 4 mmol/L but now 2
Autonomic Symptoms and signs of hypoglycaemia
Sweating
Pallor
Palpitations
Shaking
Neuroglycopenic symptoms of hypoglycaemia
Slurred speech Poor vision Confusion Seizures Loss of consciousness
Severe hypoglycaemia
Defined as an episode where a person needs third party assistance to treat
Pathophysiology of T2D
Insulin; resistance resides in liver, muscle and adipose tissue
