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Endocrinology > Carbohydrate Metabolism Biochemistry > Flashcards

Carbohydrate Metabolism Biochemistry Flashcards

1
Q

During sleep, what is the metabolic pathway that maintains [Glucose]plasma?

A

Gluconeogenesis

Total hepaic glycogen stores are barely sufficient for maintenance of blood glucose concentration during a 12hr fast. Thus glycogenolysis isn’t sufficient

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2
Q

Which organs consume most blood glucose?

A

RBCs and the brain (80% of the 200g glucose consumed)

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3
Q

Describe Glycogen.

A

Polysaccharide storage form of glucose
First line of defence against hypoglycaemia
During and immediately following a meal, glucose is converted into glycogen (glycogenesis)

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4
Q

What is glycogenesis?

A

Conversion of glucose into glycogen following a meal

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5
Q

Where is glycogen stored?

A

Liver (higher concentration) - used for glucose maintenance

Muscle (majority - because of larger body mass) - used by muscle itself

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6
Q

What is glycogenolysis?

A

Breakdown of glycogen into glucose (G6P) in the liver for maintenance of normal [glucose]plasma

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7
Q

What are the outcomes of the pentose phosphate pathway?

A
  • ribose 5-phosphate for RNA/DNA synthesis

- NADPH for redox reactions for FA biosynthesis

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8
Q

What is the committed step in PPP?

A

De-hydrogenation of G6P is the committed step

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9
Q

List the main substrate and the end products of PPP.

A

Main substrate: G6P

End products: NADPH (FA biosynthesis), H+, pentoses (RNA/DNA synthesis), and CO2

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10
Q

What is glycolysis?

A

Metabolic pathway that converts glucose into pyruvate

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11
Q

Describe the structure of glycogen

A
  • Highly branched glucan
  • Branched polysaccharide of glucose
  • Contains 2 types of glycosidic links:
    1) alpha1,4- linked glucose residues
    2) alpha1,6- branches
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12
Q

What is meant by high-capacity, low affinity transporter?

A

It means that glucose will only be transported across the membrane when it is in high concentration inside the cell.

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13
Q

Where does glycogenesis activated?

A

Liver and muscle following a meal

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14
Q

What transporter is used in glycogenesis?

A

GLUT2

High-capacity, low-affinity receptor

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15
Q

What enzymes is used to convert glucose into G6P

A

Glucokinase (hexokinase IV)

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16
Q

Is glucose kinase inhibited by increased production of G6P? (NEGATIVE FEEDBACK)?

A

No. Glucokinase is NOT inhibited by G6P, so that [G6P] increases rapidly in the liver following a meal, forcing glucose into all the major pathways of glucose metabolism: glysolysis, PPP, and glycogenesis

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17
Q

What are the major pathways of glucose metabolism?

A

Glycolysis
PPP
Glycogenesis

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18
Q

What happens to glucose in the liver following a high-carb meal?

A

Increased glucose in the liver
Converted into G6P by glucokinase

  1. Replenish glycogen stores (glycogenesis)
  2. Excess G6P enters glycolysis which:
    i- produces ATP
    ii- primarily allows for conversion of G6P into FA and TG which are subsequently transported to adipose tissue.
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19
Q

What happens to glucose in the blood following a high-carb meal?

A

Glucose is used for muscle synthesis and storage of glycogen

And in adipose tissue as a source of glycerol for TG biosynthesis

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20
Q

Briefly outline the glycogenesis pathway from glucose

A

Occurs in the liver and muscle following a meal

  1. Conversion of glucose into G6P by glucokinase
  2. Conversion of G6P into G1P by phosphyglucomutase
  3. Activation of GIP to sugar nucleotide UDP-Glucose by the enzyme UDP-glucose pryophosphorylase
  4. Transfer of glucose from UDP-glucose to glycogen by alpha1,4-links by glycogen synthase
    Glycogen branching enzymes transfers 7 residues to another glycogen chain by alpha1,6-links
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21
Q

What is the regulatory enzymes of glycogenesis?

A

Glycogen synthase

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22
Q

Describe the pathway of glycogenolysis.

A
  1. Begins with removal of a1,4-linked glucose residues in glycogen
  2. This is achieved by glycogen phosphorylate (glycogen to G1P)
  3. G1P is isomerised by phosphoglucomutase to G6P placing G6P at the top of the glycolytic pathway
  4. Glucose is released from G6P by glucose-6-phosphatase and glucose exits via GLUT2
  • rate-limiting, regulatory step in glycogeneolysis is catalysed by glycogen phosphorylase (first enzyme)
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23
Q

What is the rate-limiting, regulatory step of glycogenolysis?

A

Activity of glycogen phosphorylase (first enzyme)

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24
Q

How does G6P generated via glycogenolysis in the liever exit the liver?

A

Glucose is released from G6P by glucose-6-phosphatase, and glucose exists via GLUT2

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25
Q

Which hormones are involved in the regulation of glycogenolysis? And how.

A
  1. Glucagon - secreted by pancreatic alpha-cells; initiated by hypoglycaemia; cause rapid activation of glycogenolysis
  2. Adrenaline - secreted by adrenal medulla; initiated by acute stress/hypoglycaemia; cause rapid activation of glycogenolysis
  3. Cortisol - secreted by adrenal cortex; initiated by chronic stress; causes chronic activation of glycogenolysis
  4. Insulin - secreted by pancreatic B-cells; initiated by hyperglycaemia; causes inhibition of glycogenolysis
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26
Q

Which hormone inhibits glycogenolysis?

A

Insulin - secreted by pancreatic B-cells

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27
Q

Which hormones promote glycogenolysis?

A

Glucagon - pancreatic a-cells
Adrenaline - adrenal medulla
Cortisol - adrenal cortex

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28
Q

What kind of hormone is glucogon?

A

Peptide hormone secreted from a-cells of endocrine pancreas

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29
Q

What is the primary function of glucagon?

A

To activate glycogenolysis for maintenance of normoglycaemia

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30
Q

Describe how [Glucagon]plasma change during the day

A
  • Decreases during meals
  • Increases between meals
  • Chronically increases during fasting or on a low-carb diet
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31
Q

Give an example of a physiologic stress that activates glycogenolysis

A

Response to increased blood glucose utilisation during exercise

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32
Q

Give an example of a pathologic stress that activates glycogenolysis

A

As a result of blood loss (shock)

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33
Q

Give an example of a psychiologic stress that activates glycogenolysis

A

In response to acute/chronic threats

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34
Q

Explains the body’s glucose metabolism in response to acute stress

A

Acute stress causes activation of glycogenlysis though the action of catecholamine hormone adrenaline released by the adrenal medulla
During prolonged exercise, both glucagon and adrenaline contribute to stimulate glycogenolysis and maintenance of blood [glucose]

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35
Q

Explains the mechanism of action of glucagon

A

Glucagon binds to the glucagon receptor on hepatocytes

This is a G-protein coupled receptor (GPCR)

Causes increase in cAMP

cAMP stimulates cAMP-dependent kinase (PKA)

PKA acts on downstream targets to cause activation of glycogen phosphatase to convert glycogen into G1P

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36
Q

Which tissues most depend on glucose? And why?

A

80% of the approx.200g glucose consumed each day goes towards:

  1. RBCs - no mitochondria so cannot oxidise fuels, gain energy only from glycolysis
  2. Brain - FAs cannot cross the blood-brain barrier
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37
Q

Define gluconeogenesis

A

The synthesis of glucose from a non-carbohydrate (non-hexose) source.
E.g. lactate, pyruvate, glycerol, and certain amino acids

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38
Q

What is the purpose of gluconeogenesis?

A

Required to maintain blood glucose during fasting and starvation

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39
Q

Describe the onset of gluconeogenesis

A

Unlike glycogenolysis, which can be turned on rapidly in response to hormonal stimulation, gluconeogenesis increases more slowly, depending on changes in gene expression, and reaches maximum activity over a period of hours

  • It becomes the primary source of our [glucose]blood about 8 hours of fasting
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40
Q

What are the requirements for gluconeogenesis?

A
  1. Energy for biosynthesis - provided by metabolism of FAs released from adipose tissue
  2. Source of carbons for the formation of backbone of glucose molecule - 3 main sources:
    i) Lactate produced in tissues such as RBCs and muscle
    ii) amino acids derived from protein
    iii) glycerol released from triglycerides during lipolysis of adipose tissue
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41
Q

What provides the energy for gluconeogenesis?

A

FA metabolism in adipose tissue

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42
Q

Where does gluconeogenesis mainly occur?

A

Liver

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43
Q

What is the pathway of gluconeogenesis?

A

Opposite of glycolysis

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44
Q

What do glycolysis and gluconeogenesis have in common?

A

Same pathway. Reversible

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45
Q

A critical problem in the reverse of glycolysis for gluconeogenesis is over coming the irreversibility of 3 enzymes. List the 3 enzymes.

A
  1. Glucokinase: glucose –> G6P
  2. Phosphofructokinase-1 (PFK-1): G6P –> F6p
  3. Pyruvate kinase (PK): last enzyme to form pyruvate
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46
Q

A critical problem in the reverse of glycolysis for gluconeogenesis is over coming the irreversibility of 3 enzymes. List the 3 enzymes, and describe how they are bypassed

A
  1. Pyruvate kinase is bypassed by 2 enzymes:
    i - pyruvate carboxylase in the mitochondria
    (oxaloacetate intermediate)
    ii- PEPCK in the cytoplasm
  2. PFK1 is bypassed by fructose-1,6-bisphosphatase
  3. Glucokinase is bypassed by glucose-6-phosphatase
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47
Q

Which enzyme bypasses glucokinase?

A

Glucose-6-phosphatase

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48
Q

Where does glucokinase act?

A

Conversion of glucose to G6P (glycolysis)

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49
Q

Which enzyme bypasses PFK-1?

A

Fructose-1,6-bisphosphatase

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50
Q

Where does PFK1 act?

A

Conversion G6P to F6P (glycolysis)

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51
Q

Which enzyme(s) bypass pyruvate kinase?

A

First pyruvate carboxylase converts pyruvate to oxaloacetate

then oxaloacetate is converted to phosphoenolpyruvate by PEPCK

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52
Q

Where is glucose-6-phosphatase expressed?

A

Expressed in the lumen of ER

Requires transporters for substrates and products to get in/out

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53
Q

Comment on the expression of glucose-6-phosphatase (.

A

Glucose-6-phosphatase is an enzyme in the gluconeogenesis pathway that converts G6P to glucose.
(starvation)

Its expression is upregulated by adrenaline and glucocorticoids

and down regulated by insulin

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54
Q

What substrate can glucose not be synthesised from?

A

FAs

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55
Q

Can glucose be synthesised by fatty acids? Why?

A

NO

FAs are oxidised to acetyl-coA
2CO2s are produced, therefore lost carbons
No carbons remains to contribute to glucose carbon backbone

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56
Q

How does glucagon and adrenaline effect gluconeogenesis?

A

Decrease glucokinase
Increase glucose-6-phosphatase

Therefore, increase gluconeogenesis

Insulin inhibits gluconeogenesis

Effects is at level of gene expression

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57
Q

At what level is gluconeogenesis effects expressed?

A

Effects is at level of gene expression

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58
Q

Which cell occupy the islet of langerhans in the pancreas and by which percentage?

A

a-cell –> glucagon (20%)
b-cell –> insulin (75%)
d-cell –> somatostatin (4%)
polypeptide (pp) –> pp-hormone (1%)

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59
Q

What are the two most important energy substrates in the body?

A

Glucose and fatty acids

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60
Q

What pathways provide glucose?

A

2 pathways

  1. glycogenolysis
  2. gluconeogenesis
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61
Q

Whats the average amount of glucose present in plasma?

A

20g (80kcal; 335kj)

62
Q

Where is glycogen stored?

A

Liver (75g)

Muscle (400g)

63
Q

How many hours of fasting before glycogen stores are exhausted?

A

Approx. 16hrs

64
Q

What happens to the body metabolism for fuel after glycogen stores are exhausted?

A

De novo synthesis of non-carbohydrate compounds (gluconeogenesis)

65
Q

How are FAs stored in the body?

A

FAs are stored as esters of glycerol (TGs)

66
Q

In an average 70kg male, how much fat is usually stored?

A

15kg

67
Q

How much O2 does the brain use from total O2 consumed?

A

20%

68
Q

If the brain cannot use fatty acids as a source of energy, during starvation what alternative source can the brain use?

A

Ketone bodies

69
Q

Why can’t the brain use FAs as a source of energy?

A

FAs cannot cross blood-brain barrier

70
Q

Where does gluconeogenesis take place?

A

Liver and kidney (in prolonged fasting)

71
Q

Can gluconeogenesis take place in the muscle?

A

no

72
Q

What are the main substrates for gluconeogenesis?

A

Lactate (from anaerobic glycolysis)
Alaline (and other amino acids)
Glycerol (from breakdown of TGs in adipose tissue)

73
Q

What energy sources does muscle use?

A

Glucose: short-term exercise
FAs: rest/long-term exercise

74
Q

Can myocytes release glucose into the blood? And why?

A

No.
Absence of glucose-6-phosphatase enzyme

Glycogen stores only for its own metabolic needs

75
Q

Does muscle contribute to gluconeogenesis?

A

Yes. Provides lactate via anaerobic glycolysis which is then transported to the liver.
Gluconeogenesis does NOT take place in the muscle (only liver and kidney)

76
Q

What are the substrates and end-products of gluconeogenesis?

A

lactate, alanine, glycerol –> glucose

77
Q

What are the substrates and end-products of glycogenolysis?

A

glycogen –> G1P + Glucose

78
Q

What are the substrates and end-products of PPP?

A

G6P –> NADPH + H + pentose +CO2

79
Q

What are the substrates and end-products of FA-oxidation?

A

FA –> Acetyl CoA + CO2 + H2O + ATP + Ketone bodies

80
Q

How is glucose homeostasis controlled?

A
  • Anabolic hormone: insulin (storing glucose - glycogenesis)
  • Catabolic hormones: glucagon, catecholamines (adrenaline), cortisol, growth hormone (releasing glucose - glycogenolysis and gluconeogenesis)
81
Q

List the main enzymes of gluconeogenesis

A
  1. Glucose-6-phosphatase
  2. Fructose-1,6-bisphosphatase
  3. PEPCK
  4. Pyruvate carboxylase
82
Q

On a high-carbohydrate diet, describe what insulin does.

A

High-carb diet means large amounts of ingested glucose.
Therefore, glycolysis and glycogenesis will occur

Insulin induces gene transcription of (glycogenesis):

  1. Glucokinase
  2. PFK
  3. Pyruvate kinase
  4. Glycogen synthase

At the same time, insulin represses key enzymes of gluconeogenesis:

  1. Pyruvate carboxylase
  2. PEPCK
  3. Fructose-1,6-bisphosphatase
  4. Glucose-6-phosphatase
83
Q

On a high-FAT diet, describe what glucagon does.

A

Glucagon represses the synthesis of glucokinase, PFK-1, and pyruvate kinase, and induces the transcription of PEPCK, Fructose-1,6-bisphosphatase and glucose-6-phosphatase

84
Q

Describe the structure of insulin

A

Two peptide chains linked by 2 disulphide bonds

Alpha chain: 21AA
Beta chain: 30AA

85
Q

Where is insulin synthesised?

A

rER of pancreatic b-cells and packaged into secretory vesicles in Golgi Apparatus

86
Q

What is the precursor of insulin?

A

preproinsulin

87
Q

How is insulin synthesised?

A

First, a 24AA signal sequence is cleaved from preproinsulin by a peptidase, yielding proinsulin

Proinsulin is then split by endopeptidases into insulin and C peptide

88
Q

What is the functional purpose of C-peptide from insulin synthesis?

A

C-peptide can be measured as a marker for B-cell function, because it’s secreted into the blood in equal concentrations as insulin

89
Q

Describe the sequence of events of insulin production and secretion.

A
  1. When glucose is absorbed during a meal, B-cells take up glucose using the membrane transporter GLUT2 (low-affinity, high-capacity).
  2. On entering the cell, glucose is phosphorylated by glucokinase
  3. As glucose metabolism is stimulated, the ATP:ADP ratio in the cell increases
  4. This closes the ATP-sensitive K+ channels in the cell membrane, decreasing K+ influx and depolarising the cell
  5. Ca2+ subsequently enters the cell via voltage-gated L-type Ca2+ channels, increasing intracellular Ca2+
  6. Increase in intracellular Ca2+ activates the Ca2+-dependent proteins that cause the release of secretory granules containing insulin
90
Q

Describe the sequence of events of glucose absorption into cells?

A
  1. Insulin binds to insulin receptor (receptor tyrosin kinase; RTK)
  2. Binding of insulin causes the receptor to phosphorylate itself
  3. The receptor also recruits and phosphorylates other proteins including insulin receptor substrates (IRS1-4), which in turn dock another set of proteins
  4. This causes the recruitment of PIP3, and ultimately protein kinase B (PKB, also known as Akt)
  5. PKB results in:
    i- translocation of GLUT4 to surface (in muscle and adipose)
    ii-glycogen synthesis (in liver and muscle)
    iii- FA synthesis (in liver and adipose)
  6. PKB also inhibits:
    i- lipolysis (adipose)
    ii- gluconeogenesis (liver)
91
Q

In response to insulin, where does GLUT4 translocation occur?

A

Muscle and adipose

92
Q

In response to insulin, where does glycogen synthesis occur?

A

Liver and muscle

93
Q

In response to insulin, where does FA synthesis occur?

A

Liver and adipose

94
Q

Is insulin an anabolic or catabolic hormone?

A

Anabolic

95
Q

What’s the difference between anabolic and catabolic hormones?

A

Anabolic: building up or synthesis of complex substrates (e.g. glycogen) from simple molecules (e.g. glucose)

Catabolic: breaking down complex substrates into simple molecules to be used for fuel

96
Q

What are carbohydrates transported and stored as?

A

Transported as glucose

Stored as glycogen

97
Q

What tissues depend on a constant supply of glucose and why?

A

RBCs - They have no mitochondria and therefore cannot generate their own energy

Brain - Fatty acids cannot cross the blood-brain barrier

98
Q

What are the concentrations of regulated glucose levels during fasting and after a meal?

A

Fasted: 4-5mmol/L

After meal: 8-12mmol/L

99
Q

What are the principal regulators of carbohydrate homeostasis?

A

Insulin and glucagon

100
Q

Where does de novo synthesis of glucose happen?

A

Liver

101
Q

Whats the primary actions of insulin?

A

Drives glycogenesis in liver and muscle
Promotes uptake of glucose by tissues (muscle and adipose)
Promotes synthesis of FA and TG

102
Q

Whats the primary actions of glucagon?

A 
Drives glycogenolysis (liver)
Promotes gluconeogenesis (liver)
103
Q

What hormones are involved in liver glycogen metabolism during fasting state?

A

glucagon
(nor)adrenaline

Promote liver glycogenolysis

104
Q

What are the main enzymes during liver glycogenolysis?

A 
Glycogen phosphorylate (glycogen to G1P)
Glucose-6-phosphatase (G6P to glucose)
105
Q

What hormone is involved in liver glycogenesis?

A

Insulin

106
Q

What enzymes are involved in liver glycogensis?

A

Glucokinase

Glycogen synthase

107
Q

What enzymes are involved in muscle glycogenesis?

A

Hexokinase

Glycogen synthase

108
Q

What hormone regulates glycogenesis in the muscle?

A

Insulin

109
Q

What hormones regulate glucogenolysis in the muscle

A

(nor)adrenaline

110
Q

Why cant glucose exit muscle cells?

A

No glucose-6-phosphatase enzymes

Therefore, glucose created is used in local energy production (via glycolysis)

111
Q

Via what receptor does glucose enter muscle cells?

A

GLUT4

112
Q

Via what receptor does glucose enter liver cells?

A

GLUT2

113
Q

In gluconeogenesis, what effect does glucagon and adrenaline have?

A

Decrease glucokinase
Increase glucose-6-phosphatase

Therefore, promoting gluconeogenesis and in turn increase [glucose]plasma

114
Q

In gluconeogenesis, what effect does insulin have?

A

Increase glucokinase activity
Decrease glucose-6-phosphatase and PEPCK activity

Therefore inhibiting gluconeogenesis and in turn decreasing [glucose]plasma

115
Q

What the the three enzymes under hormonal regulation during gluconeogenesis?

A

Glucokinase
Glucose-6-phosphatase
PEPCK

116
Q

At what level is the effect of gluconeogenesis hormonal regulation?

A

Gene expression

Thus more/less enzyme is synthesised

117
Q

Which tissues does insulin mainly effect?

A

Liver
Muscle
Adipose

118
Q

What are the principal actions of insulin in the liver?

A

Increase glycogen synthesis
Increase FA synthesis
Inhibit gluconeogenesis by inhibiting PEPCK and glucose-6-phosphatase

119
Q

What are the principal actions of insulin in the muscle?

A

Increase glucose transport (GLUT4)

Increase glycogen synthesis

120
Q

What are the principal actions of insulin in the adipose?

A

Increase glucose transport (GLUT4)
Suppress lipolysis
Increase FA synthesis

121
Q

List gluconeogenesis substrates

A

pyruvate
lactate
glycerol
certain AAs

122
Q

Where does glyconeogenesis mainly occur?

A

Kidneys

Kidneys may contribute with prolonged starvation

123
Q

What is the pathway of gluconeogenesis?

A

Essentially the reversal of glycolysis

124
Q

Are are the irreversible reactions in glycolysis

A

Glucokinase
Phosphofructokinase (PFK)
Pyrivate kinase (PK)

125
Q

How are the irreversible reactions of glycolysis overcome in gluconeogenesis?

A

Glucokinase is bypassed by glucose-6-phosphatase

PFK is bypassed by fructose-1,6-bisphosphatase

PK is bypassed by 2 enzymes pyruvate carboxylase and PEPCK - oxaloacetate is the intermediate

126
Q

List types of hypoglycaemic drugs

A
  1. Sulphonylureas e.g. Tolbutamide
  2. Biguanides e.g. Metformin
  3. Thiazolindinedions e.g. Pioglitazone
  4. Incretin mimetics e.g. exentide
  5. DPP-4 inhibitros e.g. Sidagliptin
  6. SGLT2 inhibitors e.g. canagloflozin
127
Q

What does post-prandial mean?

A

After meal

128
Q

What happens post-prandial metabolism?

A
  1. insulin inhibits adipose lipolysis
  2. reduction in [FA] switches muscle to oxidation of glucose
  3. insulin stimulates uptake of glucose by adipose and skeletal muscle (GLTU4)
  4. Glucose used to make glycogen (via glycogensis in liver/muscle) and TAG (via lipogenesis in adipose)
129
Q

What is lipolysis?

A

Breakdown of lipids

Involved hydrolysis of TG into glycerol and FFAs

130
Q

What class of drug does tolbutamide belong to?

A

Sulphonylureas

131
Q

What is the mechanism of action of sulphonylureas?

A
  1. Drug binds to a receptor in the plasma membrane of pancreatic B-cells
  2. Receptor contains the ATP-sensitive K+-channel
  3. Binding of the drug closes the channel
  4. Membrane depolarises
  5. Voltage-gated Ca2+ Channels open and influx of Ca2+
  6. [Ca2+]intracellular increases stimulating exocytosis of insulin
132
Q

What is a substantial side effect of sulphonylureas?

A

Hypoglycaemia

133
Q

What class of drug does metformin belong to?

A

Biguanides

134
Q

What is metformin used to treat?

A

Most common drug used to treat T2D

135
Q

How does metformin work?

A

Reduces hepatic gluconeogenesis
Decreases endogenous glucose production (glucogenolysis)
Inhibits glucose-6-phosphatase and PEPCK
Increases peripheral insulin sensitivity

136
Q

What class of drugs doe pioglitazone belong to?

A

Thiazolidinediones

137
Q

Give an examples of a Thiazolidinedione

A

Pioglitazone

138
Q

How do Thiazolidinediones work?

A

Act at the transcription level
Improve peripheral glucose utilisation and insulin sensitivity

They are ligands of the PPAR-gamma transcription factor in adipose tissue

They stimulate expression of genes involved in TG storage

They stop inappropriate deposition of lipid in non-adipose tissue (which leads to insulin resistance) - therefore improving insulin sensitivity

139
Q

What is the incretin effect?

A

Increased stimulation of insulin secretion elicited by oral as compared with IV glucose

140
Q

What are incretins?

A

Gut hormones that are secreted from the enteroendorine cells into the blood within minutes after eating

They potentiate insulin secretion

141
Q

List the incretin hormones

A

Glucagon-like-peptide-1 (GLP-1)
Gastric inhibitory peptide (GIP)

Rapidly inactivated by the enzyme dipeptidyl peptidase-4 (DPP-4)

142
Q

What drug glass does exentide belong to?

A

GLP-1 receptor antagonist

Incretin mimetic

143
Q

How does GLP-1-agonists work?

A

Increase insulin secretion
Not cleaved by DPP4
Injected

144
Q

Give an example of a DPP4 inhibitor

A

Sidagliptin

145
Q

How do DPP4 inhibitors work?

A

Increase endogenous GLP-1 therefore increases insulin secretion

146
Q

are DPP4 drugs oral or IV?

A

Oral

147
Q

What drug can be given to increase endogenous GLP-1?

A

DPP4 inhibitor e,g, Vildogliptin

148
Q

What are SGLT2 inhibitors?

A

Inhibit renal re-uptake of glucose from filtrate

149
Q

What is the effect of SGLT2 inhibitors?

A

Decrease hyperglycaemia

150
Q

What are the cardiovascular effects of SGLT2 inhibitors?

A

Decrease BP

EMPA-REG and CANVAS studies show reduced cardiovascular mortality and hospitalisation

151
Q

Give examples of SGLT2 inhibitors

A

Canagliflozin
Dapagliflozin
Empagliflozin

Endocrinology (11 decks)

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