What is diabetes? - introduction

Question 1

Define diabetes

Answer 1

Insufficient insulin to maintain glucose homeostasis

A group of metabolic diseases characterised by hyperglycaemia resulting from defects in insulin secretion, insulin action or both

Question 2

Define type 1 diabetes

Answer 2

Absolute insulin deficiency - beta cell failure

Question 3

Define type 2 diabetes

Answer 3

Inadequate insulin production/secretion and/or insulin resistance

Question 4

What is the HbA1c of someone with diabetes?

Answer 4

>/= 48m/m

Question 5

What is the fasting glucose of someone with diabetes?

Answer 5

>/= 7mmol/L

Question 6

What is the 2hr glucose in OGTT in someone with diabetes?

Answer 6

>/= 11.1mmol/L

Question 7

What is the random glucose of someone with diabetes?

Answer 7

>/= 11.1 mmol/L

Question 8

What is the normal range for HbA1c?

Answer 8

= 41 m/m

Question 9

What is the normal range for fasting glucose?

Answer 9

= 6mmol/L

Question 10

What is the normal range for 2hr glucose in OGTT?

Answer 10

= 7.7 mmol/L

Question 11

What is the prediabetic range for HbA1c?

Answer 11

42-47 mmol/L

Question 12

What is the prediabetic fasting glucose range?

Answer 12

6.1-6.9 mmol/L

Question 13

What is the prediabetic range for 2hr glucose in OGTT?

Answer 13

7.8 - 11 mmol/L

Question 14

What are the roles of insulin?

Answer 14

• Converts glucose –> glycogen in the liver
• Fatty acids –> triglycerides
• Amino acids –> protein

Question 15

What is th target tissue for glucagon?

Answer 15

Liver

Question 16

What are the roles of glucagon?

Answer 16

• Glycogen –> glucose
• Triglycerides –> fatty acids

Question 17

What are incretins?

Answer 17

peptides that enhance insulin secretion

Question 18

Where are incretins released from?

Why does this matter?

Answer 18

GI tract

This means that after someone ingests glycose, the total amount of insulin secreted is higher than if the same amount of glucose had been administered IV

Question 19

What are the three peptides (incretins) that enhance insulin secretion?

Answer 19

1. Cholecystokinin (CCK)
2. Glucagon-like intestinal peptide 1 (GLP-1)
3. Gastric inhibitory peptide (GIP)

Question 20

How to incretins work?

Answer 20

Act in a feed forward manner to prime the beta cells to produce insulin

Question 21

What are the three things that glucagon stimulates?

Answer 21

1. Glycogenolysis
2. Gluconeogenesis
3. Ketogenesis

Question 22

Define glycogenolysis

Answer 22

Breakdown of glycogen to glucose

Question 23

Define gluconeogensis

Answer 23

Formation of glucose from non-carbohydrate substrates e.g. pyruvate, fats, proteins

Question 24

Define ketogenesis

Answer 24

Production of ketone bodies from the breakdown of fatty acids and Ketogenic amino acids

Question 25

What type of disorder is type 1 diabetes?

Answer 25

Autoimmune

Question 26

What happens during the autoimmune response in type 1 diabetes?

Answer 26

1. Innate immune cells enter the pancreatic islets (priming)
2. Antigens trigger T cells in the pancreatic lymph node
3. T cells arrive from lymph nodes - insulitis ensues
4. No intervention - disease onset. Intervention - remission