Diabetes Flashcards
Description of glucagon
29 amino acid polypeptide
Potent hyperglycaemic agent
Major target = liver
What does glucagon promote?
- Glycogenolysis- glycogen to glucose
- Gluconeogenesis - synthesis of glucose from lactic acid and non carbs
- Release of glucose to blood from liver cells
Description of insulin
51 amino acid polypeptide
Two aa chains linked by disulphide bonds
Synthesised as part of pro insulin
Cleaved to make functional insulin
Potent hypoglycaemic agent
What does insulin promote?
Enhances transport of glucose into cells
Counters metabolic activity that would enhance BGL
Insulin is what type of receptor?
Tyrosine kinase enzyme
What does insulin binding trigger:
- Catalyses oxidation of glucose for ATP production
- Polymerises glucose to form glycogen
- Converts glucose to fat
What is the NHS definition of Diabetes
Diabetes is a lifelong condition that causes a persons blood sugar level to become too high
Overview of diabetes
A disease of high glucose, but also BP
Common and expensive
Associated with significant morbidity
With training and support can be an aged well
Diagnosing diabetes Mellitus
- Urine analysis for glucose
- Blood glucose values
- Oral glucose tolerance test - Gold standard
- Glycated haemoglobin - HbA1c
Are urine analysis for glucose useful
Useful but not enough
Not sensitive or specific
But glucose in urine should always be investigated
Values for random glucose test
Diabetes mellitus if more than 11.1 mmol/L
Values for fasting glucose test
Diabetes mellitus will have range bigger than 7.0 mmol/L
How to conduct oral glucose tolerance test
Fasting state
Measure glucose at time 0hrs
75g glucose drink over 5mins
Wait 2hrs
Measure glucose at time 2hrs
What is the normal range for glycated haemoglobin
48-58 mmol/mol
What is the role of insulin
Anabolic hormone
- maintain supply of glucose in tissues
- regulates metabolism in muscle
- promotes protein synthesis
- inhibit breakdown of fat
What is the precursor of insulin
Proinsulin
What is type 1 diabetes
Genetic cause
Where body’s IMS attacks and destroys the cells that produce insulin
What is type 2 diabetes
Where the body doesn’t prod enough insulin, or the body’s cells don’t react to insulin
What is gestational diabetes?
During pregnancy, some women have high levels of BG
Body unable to produce enough insulin to absorb it all
What is the onset of type 1 diabetes
Under 40 years
Population of Britain that have type 1
0.3%
Describe a glucose profile for diabetes patient
Dawn phenomenon in diabetes patient: high BG Cortisol levels high in the morning
Evening meal: BGL rise
Mean BG higher for patient with diabetes, peaks are more pronounced and more variability
Values for hypoglycaemia
4 mmol/L
Symptoms of both type 1 and type 2 diabetes
Weight loss
Tiredness/ coma: brain not getting enough glucose
Infection - as BGL increases, immunity deceases (candidiasis, urine infection, abscesses)
Osmotic symptoms
What are osmotic symptoms of diabetes
Polyuria: glucose excreted in large volume of urine
Thirst: polydipsia
Blurred vision: high BGL cause water to be pulled out of lens. Lens changes shape causing blurred vision.
How to test patients for diabetes
If have symptoms of diabetes only need 1 diagnostic test to confirm
If don’t have symptoms need 2 tests to confirm diabetes bcs some people asymptomatic
Why is glycogen haemoglobin useful
Reflect previous 10 weeks of ambient circulating glucose
A good tool for monitoring whether an individual has good long term control of diabetes
Diabetic results for glycogen haemoglobin
More than 48mmol/mol
Who is glycated haemoglobin inappropriate for?
For all children and young people
Pregnant women
Patients on med that may cause rapid glucose rise (steroids)
Suspicion of type 1 diabetic symptoms for less than 2 months
What should you do after diagnosis of diabetes
Obtains a HBA1C (to see starting point of diabetes), check kidney function and retinography - eyes and feet
Symptoms of type 1
feeling very thirsty.
urinating more frequently than usual, particularly at night.
feeling very tired.
weight loss and loss of muscle bulk.
itchiness around the genital area, or regular bouts of thrush (a yeast infection)
blurred vision caused by the lens of your eye changing shape.
What is Osmotic diuresis
Polydipsia
Polyuria
Dehydration
Increased glucose causes excessive water, electrolyte (Na, K) and glucose loss in the urine
Types of ketone bodies
Acetone
Acetoacetate
Beta hydroxybutyrate
