Srikal Dhar - Diabetes Flashcards

1
Q

How is insulin involved in glucose metabolism

A
  1. Insulin binds to insulin receptor
  2. Triggers signalling cascade that causes translocation of GLUT4 into plasma membrane
  3. GLUT4 goes to surface
  4. Glucose enters cell via GLUT4
  5. Glucose is converted to pyruvate via glycolysis
  6. Pyruvate is converted to acetyl CoA via pyruvate oxidation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the primary distribution of the GLUT 1 transporter (Where is it usually found)

A

Endothelium, erythrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the primary distribution of the GLUT 2 transporter?

A

Kidney, small intestine, liver, pancreatic beta cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the primary distribution of the GLUT 3 transporter?

A

Neurones, placenta

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the primary distribution of the GLUT 4 transporter?

A

Skeletal muscle, adipose tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which glucose transporters are insulin independent

A

GLUT 1, 2 & 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which glucose transporters have a high affinity for glucose?

A

GLUT 3 & 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Which glucose transporters have a low affinity for glucose?

A

GLUT 2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the affinity for glucose of GLUT 1?

A

Baseline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How does SGLT1 and SGLT2 transport glucose?

A
  • Active transport of glucose into luminal epithelial cells in the kidney and small intestine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the core defects in T2DM?

A
  • Insulin resistance in muscle and the liver
  • Impaired insulin secretion by the pancreatic β-cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What contributes to progressive failure in the function of β-cells?

A

β-cell resistance to the incretin ‘glucagon-like peptide 1’ (GLP1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is prediabetes?

A

When blood sugar is higher than usual but not high enough to be diagnosed with Type 2 diabetes however are at high risk of developing it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Is prediabetes reversible?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does trending mean in terms of T2DM?

A

When there is higher than usual blood sugar.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are other names for prediabetes?

A
  • Borderline diabetes
  • Impaired Glucose Regulation (IGR)
  • Non-diabetic hyperglycaemia
  • Impaired fasting glucose (IFG) WITH Impaired Glucose Tolerance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the symptoms of prediabetes?

A

There are none, if there are T2DM has already developed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What modifiable factors increase the risk of diabetes

A
  • Smoking
  • History of high BP
  • Being overweight (especially centripetal obesity)
  • Sedentary lifestyle
  • Alcohol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What non-modifiable factors increase the risk of diabetes?

A
  • Older age
  • White and over 40
  • Afro- caribbean, black african, south asian and over 25
  • Having relative with diabetes
  • Gestational diabetes
  • PCOS
  • Mental health conditions
  • Anti-psychotic medications
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Why has the NHS diabetes prevention programme been implemented?

A
  • Many cases of Type 2 diabetes are preventable through behavioural interventions
  • Diabetes treatment currently accounts for 10% of the annual NHS budget
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the aims of the NHS diabetes prevention programme?

A
  • Reduce the incidences of T2DM
  • Reduce the incidence of complications associated with diabetes
  • Reduce health inequalities associated with the incidence of diabetes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the complications associated with diabetes?

A

Heart, stroke, kidney, eye and foot problems

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the 3 core goals of the NHS DPP?

A
  • Achieving a healthy weight
  • Achievement of dietary recommendations
  • Achievement of CMO physical activity recommendations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Who is eligible for the programme?

A
  • Those with non diabetic hyperglycaemia (Hba1c 42-47 or fasting plasma glucose of 5.5-6.9)
  • NDH within last 12 monts
  • Most recent blood reading used
  • 18 years and over
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

List the causes of hyperglycaemia (RULING HIVE)

A
  • Increased Reabsorption
  • Decreased glucose Uptake
  • Increased Lipolysis
  • Inflammation
    -Neurotransmitter dysfunction
  • Increased Glucagon secretion
  • Increased Hepatic glucose production
  • Decreased Insulin secretion
    -Vascular insulin resistance
  • Decreased incretin Effect
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How does increased glucose reabsorption cause hyperglycaemia

A

Increased renal glucose reabsorption by the sodium/glucose co transporter 2 (SGLT2) and increased threshold for glucose spillage in the urine contribute to the maintenance of hyperglycaemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How does decreased glucose uptake cause hyperglycaemia

A
  • Beta cell failure therefore less insulin secreted therefore hyperglycaemia
28
Q

How does increased lipolysis cause hyperglycaemia

A

Insulin resistance in adipocytes results in accelerated lipolysis and increased plasma free fatty acid levels, both of which aggravate the insulin resistance in muscle and the liver and contribute to beta cell failure

29
Q

How does inflammation cause hyperglycaemia?

A

Inflammation activates and increases the expression of several proteins that suppress insulin signalling pathways, making the human body less responsive to insulin and increasing the risk for insulin resistance

30
Q

How does neurotransmitter dysfunction cause hyperglycaemia?

A

Resistance to the appetite suppressive effects of a number of hormones as well as low brain dopamine and increased brain serotonin levels contribute to weight gain, which exacerbates the underlying resistance

31
Q

How does increased glucagon secretion cause hyperglycaemia

A

Over time after lots of insulin is being produced, alpha cells become insulin resistant, glucagon secretion increases and blood glucose increases

32
Q

How does increased hepatic glucose production cause hyperglycaemia?

A

Increased glucagon levels and enhanced hepatic sensitivity to glucagon contribute to the excessive glucose production by the liver

33
Q

How does decreased insulin secretion cause hyperglycaemia?

A

Beta cell failure due to GLP1 resistance and/or insulin resistant adipose muscle and liver tissue.

34
Q

How does vascular insulin resistance cause hyperglycaemia

A

Prolonged exposure to high levels of insulin causes increased vasculature resistance

35
Q

How does decreased incretin effect cause hyperglycaemia

A

GLP1 stimulates beta cells to secrete insulin

36
Q

What are the functional effects of insulin on the liver?

A
  • INCREASED glucose uptake
  • INCREASED glycogenesis
  • DECREASED glycogenolysis
  • DECREASED gluconeogenesis
  • DECREASED lipolysis
37
Q

What are the functional effects of insulin on fat?

A
  • INCREASED glucose uptake
  • DECREASED lipolysis
  • INCREASED lipogenesis
38
Q

What are the functional effects of insulin on muscle?

A
  • INCREASED glucose uptake
  • INCREASED glycogenesis
  • INCREASED protein synthesis
  • DECREASED protein catabolism
39
Q

What is the difference in pathogenesis between T1DM and T2DM?

A

Type 1 - Very little/no insulin produced at all
Type 2 - Little insulin produced AND insulin resistant cells

40
Q

When in a fasting glucose state what is the range of blood sugar which indicates normal metabolism?

A

<5.5 mmol/L

41
Q

When in a fasting glucose state what is the range of blood sugar which indicates impaired fasting glucose?

A

5.5-6.9 mmol/L

42
Q

When in a fasting glucose state what is the range of blood sugar which indicates impaired glucose tolerance?

A

<7mmol/L

43
Q

When in a fasting glucose state what is the range of blood sugar which indicates diabetes?

A

≥ 7 mmol/L

44
Q

When in a post prandial glucose state what is the range of blood sugar which indicates normal metabolism?

A

<7.8 mmol/L

45
Q

When in a post prandial glucose state what is the range of blood sugar which indicates impaired glucose tolerance?

A

7.8-11.1mmol/L

46
Q

When in a post prandial glucose state what is the range of blood sugar which indicates diabetes?

A

≥ 11.1mmol/L

47
Q

When a random blood glucose is taken what is the range of blood sugar which indicates diabetes?

A

≥ 11.1 mmol/L

48
Q

What does impaired fasting glucose indicate?

A

Predominantly hepatic insulin resistance that leads to continuous glucose output from the liver

49
Q

What does impaired glucose tolerance indicate?

A

Predominantly muscle insulin resistance plus impaired post prandial insulin release results in poor cellular glucose uptake

50
Q

What are the 3 main diabetes symptoms?

A

Polydipsia
Polyuria
Polyphagia

51
Q

What is polydipsia and what is it caused by?

A

An INCREASE in thirst
- When blood glucose levels get high, your kidneys produce more urine to remove excess glucose, resulting in thirst.

52
Q

What is polyuria and what is it caused by?

A

FREQUENT URINATION
- When blood glucose levels get high, your kidneys produce more urine to remove excess glucose, resulting in more water filtered out therefore increased need to urinate

53
Q

What is polyuria and what is it caused by?

A

INCREASE IN APPETITE
- When glucose can’t enter cells to be used for energy causing hunger
- Can either be due to low insulin levels or insulin resistance.

54
Q

What is needed for a diabetes diagnosis?

A
  • Symptoms + 1 positive blood glucose test
  • No symptoms + multiple postive blood glucose tests
55
Q

What is the renal threshold for glucose?

A

When the blood glucose level exceeds 160-180 mg/dL, the proximal tubule cannot reabsorb more glucose and begins to excrete glucose in the urine

56
Q

What is a HbA1c?

A

A haemoglobin that has become glycosylated (chemically linked to a sugar)

57
Q

Are enzymes needed for the formation of HbA1c?

A

No

58
Q

What sugars can formation of HbA1c involve?

A

Glucose, fructose, galactose

59
Q

Why can HbA1c levels be used to diagnose and monitor diabetes?

A

Formation of HbA1c occurs proportionately to plasma glucose levels

60
Q

What are the advantages of using HbA1c as a diagnostic tool for diabetes?

A
  • Takes into account blood glucose levels for 2-3 months
  • Easy to measure as fasting not needed and isnt affected by stress, diet or exercise
  • Cheap
61
Q

What are the disadvantages of using HbA1c as a diagnostic tool for diabetes?

A
  • Only approximate
  • Not reliable in certain conditions (eg. pregnancy, renal failure, sickle cell)
62
Q

How does metformin work

A

Reduces amount of sugar liver releases into blood
- Suppresses enzymatic reactions of gluconeogenesis
- Inhibition of glucagon action
- Downregulation of gluconeogenic genes
- Makes body respons better to insulin by stimulating GLUT 4 translocation

63
Q

What are the advantages of taking metformin?

A
  • Broad targets (AMPK)
  • Cheap
  • Lower risk of hypoglycaemia
  • No weight gain, possible weight loss
  • Associated w/ lower BP
  • Associated w/ lower LDL cholesterol level
  • May have protective effect against kidney and pancreatic cancer
64
Q

What are the side effects of taking metformin?

A
  • Vomiting
  • Diarrhoea
  • Stomach-ache
  • Lack of appetite
65
Q

What is the EAST framework for behavioural change?

A