Topic 9- Insulin and Diabetes

Question 1

Define diabetes mellitus

Answer 1

metabolic disorder characterised by abnormal chemical reactions that alter normal metabolic processes

Question 2

Define diabetes

Answer 2

a disease that causes polyuria, glucosuria, polyphagia, polydipsia

Question 3

What is diabetes insipidus?

Answer 3

characterised by abnormal secretions of ADH

Question 4

What is insulin?

Answer 4

secreted from B cells of the Islets of Langerhans in the pancreas, in response to increased blood glucose level

Question 5

What are the two main glucose transporters and what do they do?

Answer 5

GLUT 2: bidirectional flow in the liver, pancreas and renal tubules (all these organs need bidirectional flow of glucose)
GLUT 4: one-directional, skeletal muscles and adipose tissue

Question 6

Glycogenesis

Answer 6

glucose –> glycogen

Question 7

Lipogenesis

Answer 7

glucose –> triglycerides

Question 8

Glycogenolysis

Answer 8

glycogen –> glucose

Question 9

Gluconeogenesis

Answer 9

glucose from non-carb sources

Question 10

Lipolysis

Answer 10

triglyceride breakdown

Question 11

What is glucagon/

Answer 11

secreted from alpha cells in the Islets of Langerhans in the pancreas in response to low blood glucose levels

Question 12

What are ketone bodies?

Answer 12

resulting from no glucose breakdown during ATP production - fatty acids cannot enter the kreb’s cycle without glucose so instead they are sent to the liver where ketones are produced as energy

Question 13

Why are ketones harmful in high levels?

Answer 13

makes blood acidic

Question 14

What occurs in a fed state?

Answer 14

increased insulin, decreased glucagon

increased: lipogenesis, glycogenesis, protein synthesis
decreased: glycogenolysis, gluconeogenesis, lipolysis, ketogenesis

Question 15

What occurs in a fasted or starved state?

Answer 15

increased glucagon, decreased insulin

decreased: lipogenesis, glycogenesis, protein synthesis
increased: glycogenolysis, gluconeogenesis, lipolysis, ketogenesis

Question 16

What kind of inflammation is diabetes?

Answer 16

stress response or para-inflammation

Question 17

What is type 1 diabetes?

Answer 17

catabolic disorder characterised by:

• lack of insulin
• B cell destruction
• elevated BGL (hyperglycaemia)
• increased fat/protein breakdown
• at the level of the pancreas

Question 18

What is the difference between type 1A and 1B?

Answer 18

1A: immune-mediated destructionof beta cells by T cells
1B: idiopathic, no immune component

Question 19

What is type 2 diabetes?

Answer 19

insulin resistance caused by:

• genetic predisposition
• obesity
• certain ethnicities

Question 20

What occurs to cells over time due to hyperglycaemia?

Answer 20

hypotrophy, hypoplasia, apoptosis, glucose toxicity, lipotoxicity

Question 21

How are diabetes and obesity related?

Answer 21

obesity puts the body in a pro-inflammatory state

insulin usually suppresses inflammatory mediators, but insulin resistance = increased inflammation

Question 22

polyphagia

Answer 22

excessive hunger

Question 23

polyuria

Answer 23

excessive urination

Question 24

polydipsia

Answer 24

excessive thirst

Question 25

glucosuria

Answer 25

glucose in urine

Question 26

Treatment for type 1?

Answer 26

lifelong insulin injection

Question 27

Treatment for type 2?

Answer 27

diet and exercise modifications

Question 28

How is diabetes detected?

Answer 28

fasting blood glucose levels, oral blood glucose, glycated haemoglobin test

Question 29

Fasting blood glucose levels

Answer 29

normal: less than 5.5mmol/ DM: more than 7.7mmol/L

Question 30

OGTT (oral blood glucose test) levels

Answer 30

normal: less than 7.8mmol/L DM: 11.1 mmol/l

Question 31

Glycated haemoglobin levels

Answer 31

normal: less than 6.5% DM: greater than 6.5%

Question 32

Casual BGT levels

Answer 32

normal: less than 11.1mmol/L DM: greater than 11.1mmol/l

Question 33

What is pre-diabetes?

Answer 33

can be reversed elevated BGL but not in range of DMT2 early detection and changes can prevent onset of DMT2

Question 34

Acute complications of hypoglycaemia?

Answer 34

- failure to eat - incorrect insulin doage - increased exercise - excessive alcohol - altered cerebal functions: headache, disturbed behaviour - ANS changes: anxiety, sweating, cool clammy skin

Question 35

Chronic complications of diabetes?

Answer 35

macrovascular, microvascular, neurophaties,

Question 36

Macrovascular

Answer 36

cerebral vascular, coronoary artery, peripheral vascular, atherosclerosis, stroke, HBP

Question 37

Microvascular

Answer 37

nephropathies, retinopathies

Question 38

Neuropathies

Answer 38

somatic, autonomic

Question 39

What are some other complications of diabetes?

Answer 39

- thickening of basement membrane - hypoxia - glycostation - protein and glucose accumulating in vessels - damaged cells - glucose --> sorbitol = increased pressure/water influx - damaged myelin - impaired nerve transmission

Question 40

What occurs in retinopathies?

Answer 40

damage to blood vessels, cataracts

Question 41

What occurs in nephropathies?

Answer 41

-basement membrane thickening --> efferent and afferent arterioles, glomeruli, Bowman's capsule, nodular lesions, glomerulosclerosis

Question 42

What occurs in neuropathies?

Answer 42

- ischaemia to nerves - damage to myelin = slow impulses - decreased ability to empty bladder, cardiac response, vasomotor function

Question 43

Foot uclers

Answer 43

- decreased blood supply and nerve damage - decreased pain = decreased sensory information --> unnoticed ulcers - poor circulation and immune function --> poor healing: infections, gangrene, amputations