Week 1 (L1-L3) Flashcards
Main factors contributing to cardiovascular disease (CVD)
Smoking
High BP
High cholesterol
What genes affect obesity susceptibility:
leptin: secreted by adipose tissue affecting energy expenditure
Leptin resistance —> less negative feedback from adipose tissue to hypothalamus.
What can obesity lead to
- Type 2 diabetes
- cardiovascular disease
- High cholesterol level in bile acid —> gallstones –> NAFLD
What is diabetes mellitus
chronic hyperglycaemia – disturbed carbohydrate and lipid metabolism.
due to insulin resistance and lack of insulin production
Fasting glucose readings
The test to see how the body handles glucose metabolism in a fasting state.
If the fasting glucose readings is relatively high, it indicates impaired fasting glucose
- prediabetic, because liver produces exceeding levels due to IR.
2h plasma glucose readings
The test is doneto check how the body deals with influx of sugar
If the 2h plasma glucose readings is high, then it means impaired glucose tolerance
IMPAIRED ABILITY TO DISPOSE GLUCOSE
Diabetes (fasting glucose/glucose tolerance readings)
Fasting glucose: ≥7.0 mmol/l
2h plasma glucose: ≥11.1 mmol/l
Why isn’t urine glucose tested anymore?
Some people have higher renal reabsorption threshold, some lower.
what are osmotic symptoms in the context of diabetes
Classic symptoms of diabetes: polyuria or polydypsia
DM: when the body is trying to rid of the glucose.
DI: insensitivity to ADH or lack of its production.
Why are 2 confirmatory readings required when there are no osmotic symptoms of diabetes
Fluctuation of glucose levels: these criteria usually require confirmation by repeat testing on a different day if there are no classic symptoms
Type 1 diabetes consequences
No insulin secretion:
1. muscle cells have no glucose uptake
2. ketosis happens, FFA will undergo lipolysis to turn to another fuel, ketone
Type 2 diabetes mellitus consequences
Insulin resistance:
Muscle cells cannot utilise blood glucose well.
ketosis in T1 and T2 diabetes mellitus
There is ketosis in T1 but no ketosis in T2.
What happens in ketosis
Body’s fasting state:
adipose tissue will breakdown triglycerides and release FFA.
FFA undergoes beta-oxidation turning to acetyl-CoA.
Acetyl-CoA accumulation lead to conversion to ketone.
What is diabetic ketoacidosis
In Type 1 Diabetes Mellitus, insulin insufficiency will lead to the accumulation of ketones.
Acidic ketone bodies accumulation in the circulation will decrease the pH of the blood.
Diuresis in diabetes mellitus
high blood glucose which exceeds max renal reabsorption, glucose can act as an osmolyte.
Macrovascular complications of hyperglycaemia
- Atheroma (plaque/fatty tissue build up in artery)
- cardiovascular disease
- peripheral vascular disease (foot ulcer)
Risk of micro/macrovascular damage by blood sugar
Macrovascular is linear, microvascular is a curve
Examples of incretins
- Glucagon like peptide 1 (GLP 1)
- GIP
abnormal incretin in T2 diabetes
- Impaired incretin effects
- some incretins are low (GLP-1) in T2 diabetes
- DPP inhibitor is used in T2 diabetes, because the enzyme, DPP 4, will inactivate incretins
Microvascular complications of hyperglycaemia
- retinopathy
- nephropathy
What do incretins do
produced in the GI after food intake,
1. increase insulin secretion
2. suppresses appetite
how does T2 diabetes affect incretin
T2DM will suppress incretin effect
hyperglycaemia causing neuropathy
- The accumulation of AGEs in nerve vessels, for example, inducing inflammation.
- Atherosclerosis can damage both blood vessels and lead to poor perfusion to nearby nerves, especially in peripheries)
What are AGEs (advanced glycation end products) in diabetes
due to chronic hyperglycaemia, glucose will bind to proteins, lipids, etc.
T1 vs T2 diabetes (main apparent differences)
T1 is often associated with weight loss and being thin.
T2 is caused by obesity, and often feeds back to weight gain.
Type 1 diabetes treatment and complication
- Insulin injections
- beware of hypoglycaemia
Type 2 diabetes treatment options
- Diet changes and exercise
- Drugs to sensitise insulin
