Obesity & Developmental Programming

Question 1

What is the Barker hypothesis?

Answer 1

Early life environmental manipulation impacts later physiological changes and disease risk

Question 2

What is low birth rate associated with? (7)

Answer 2

• hypertension
• type 2 diabetes
• hyperlipidaemia
• metabolic syndrome
• ishcaemic heart disease
• osteoporosis
• depression

Question 3

The Dutch Hunger Winter

Answer 3

• famine during early pregnancy: increased adult hypertension
• famine during late pregnancy: increased adult obesity and glucose intolerance

Question 4

Predictive Adaptive Response

Answer 4

• restricted nutrients leads to thrifty adaptation
• if post natal environment is poor, adaptation is an advantage
• if post natal environment is rich, leads to obesity and metabolic syndrome

Question 5

What does 11B-hydroxysteroid dehydrogenase 2 do?

Answer 5

Coverts active corticosterone into inactive

Question 6

What does 11B-hydroxysteroid dehydrogenase 1 do?

Answer 6

Coverts inactive corticosterone into active

Question 7

What effects does corticosterone have in a foetus?

Answer 7

Has a maturing effects, stops growth

Question 8

How does corticosterone lead to adverse programming outcomes?

Answer 8

Altered cell number: division, apoptosis

Altered gene expression (transcription)

Question 9

What is obesity?

Answer 9

Abnormal or excessive fat accumulation that presents a risk to health

Question 10

What is the heritability of obesity?

Answer 10

Between 40-70%

Question 11

What are the strongest polygenic obesity associations?

Answer 11

• fat mass and obesity associated (FTO) gene

- melanocortin 4 receptor (MC4R) gene

Question 12

Why is protein good for fat loss?

Answer 12

Good the doc effect
Satiety
Preserves lean mass

Question 13

What is key for weight loss?

Answer 13

Calorie deficit

Question 14

What happens to leptin resistance with a high energy diet?

Answer 14

Increased leptin resistance even with exercise

Question 15

How does the gut microbiome contribute to obesity?

Answer 15

• 2 main bacterial phyla: bacteriodetes and firmicutes

- higher proportion of firmicutes is associated with obesity

Question 16

How does sleep affect obesity?

Answer 16

• increased cortisol: increased glucose and decreased insulin: leads to decreased glucose tolerance and insulin resistance
• altered thermoregulation and increased fatigue leads to decrease in physical activity
• appetite dysregulation: increased ghrelin and decreased leptin leads to increased caloric intake and weight gain
• obesity then causes sleep disorder, anxiety and depression which contribute to poor sleep and continues the cycle

Question 17

How does a dysbiosis gut microbiota cause obesity?

Answer 17

• increases gut permeability
• increases endotoxemia
• increases inflammation
• increases adiposity
• increases insulin resistance