Lecture 35 - Diabetes Type 2

Question 1

What distinguished Type 1 from Type 2 diabetes

Answer 1

Type 1: Autoimmune destruction of pancreatic B cells - little to no insulin produced
Type 2: Insulin resistance and impaired insulin secretion, typically linked to lifestyle

Question 2

Symptoms of type 2 diabetes

Answer 2

Thirst, frequent unrination, fatigue, blurred vission. Can lead to vascular diseases and elevated blood TAG levels

Question 3

What is diagnostic fasting glucose level for diabetes

Answer 3

Fasting glucose >7mmol/L or random 11.1> mmil/L is diagnostic for diabetes

Question 4

What is the diagnostic HbA1c level for diabetes

Answer 4

HbA1c >50mmol/mol indicates diabetes

Question 5

What is glycated haemoglobin HbA1c and why is it used for diagnosis

Answer 5

HbA1c reflects the average blood glucose level over the past 3 months by measuring glucose bound to haemoglobin in RBCs. It provides a long-term view of glucose control.

Question 6

What does a glucose tolerance test (GTT) measure

Answer 6

GTT measures how the body handles glucose after an oral glucose load. Blood glucose is monitored for 2 hrs after ingestion

Question 7

How do glucose tolerance test results differ for normal, pre diabetic, and diabetic individuals?

Answer 7

Normal: Glucose returns baseline after 2 hrs
Prediabetic: Elevated fasting glucose and slower return to baseline
Diabetic: Elevated fasting glucose and impaired return to baseline

Question 8

What is Insulin resistance

Answer 8

IR is when cells fail to respond adequately to insulin, leading to elevated blood glucose levels and compensatory insulin production.

Question 9

Name two biological features of insulin resistance

Answer 9

• Decreased glucose uptake
• Increased gluconeogenesis

Question 10

What dysregulations in glucose and lipid metabolism occur in insulin resistance

Answer 10

Reduced glucose uptake, increased gluconeogenesis, elevated blood FFAs and impaired lipolysis, leading to hyperglycaemia and elevated blood TAGs.

Question 11

How does IR contribute to fatty liver in diabetes

Answer 11

IR leads to excess fat accumulation in the liver due to impaired fatty acid oxidation and excess lipogenesis, causing fatty liver

Question 12

How does exercise enhances insulin sensitivity

Answer 12

Exercise activated AMPK, which promotes glucose uptake in muscle cells and increases GLUT4 translocation, reducing blood glucose levels

Question 13

What drug enhance insulin sensitivity and how does it work

Answer 13

Metformin - enhances insulin sensitivity by activating AMPK, which reduces gluconeogenesis in the liver and lowers blood glucose

Question 14

What are treatments aiming for

Answer 14

Treatments are mainly aimed at promoting insulin secretion and improving insulin sensitivity

Question 15

Name two drugs that promote insulin secretion and describe how they work

Answer 15

• Sulfonyureas: Block K+ channels in B cells, triggering Insulin release
• GLP-1 Agonist: stimulates insulin secretion in response to nutrients

Question 16

What are SGLT2 inhibitors and how do they work

Answer 16

SGLT2 inhibitors block glucose reabsorption in the kidneys, allowing excess glucose to be excreted in urine and lowering blood glucose levels

Question 17

What is the role of GLP-1 in treating type 2 diabetes

Answer 17

GLP-1 potentiates insulin secretion by stimulation B cells in response to nutrient intake. GLP1 agonists are used to treat type 2 diabetes

Question 18

How does insulin resistance impair glucose uptake in tissues

Answer 18

Insulin resistance reduces phosphorylation of insulin signalling proteins, impairing GLUT4 translocation and glucose uptake in muscle and adipose tissue

Question 19

What are advanced glycation end products AGE, why are they problematic

Answer 19

AGE products form when glucose binds to proteins. They promote inflammation and contribute to vascular complications like atherosclerosis in diabetics

Question 20

How does insulin affect fat storage in adipose tissue

Answer 20

Insulin stimulates LPL to hydrolyse TAGs from chylomicrons and VLDL allowing FAs to enter adipocytes and be re synthesised into TAGs for storage

Question 21

What is AMPK and how is it involved in glucose metabolism

Answer 21

AMPK is an enzyme activated by exercise and metformin that stimulates glucose uptake in muscles cells, increase fatty acid oxidation, reduced gluconeogenesis, thereby lowering blood glucose levels

Question 22

How does exercise affect insulin response curves

Answer 22

Exercise improves insulin sensitivity, shifting the insulin response curve so that less insulin is required to lower blood glucose effectively

Question 23

What happens in B cells during insulin resistance over time

Answer 23

Prolonged insulin resistance leads to B cell hyperplasia and increased insulin production initially, but eventually, B cell function deteriorates, reducing insulin secretions