W.6: Alteration in energy balance

Question 1

What is the compound in which a lean healthy person stores the most energy?

Answer 1

Fat

Question 2

The tissue that exclusively burns glucose?

Answer 2

Retina and RBCs

Question 3

In normal conditions, ratio of brain glucose utilization compared to the entire body in percent?

Answer 3

60-70%

Question 4

BMR is influenced by (6 factors)

Answer 4

Age, body surface, temperature, sex, degree of nutrient supply, emotional state

Question 5

Indirect calorimetry

Answer 5

Measurement of exhaled CO2 and inhaled O2 in an isolated system

Question 6

Conditions with increased energy need

Answer 6

Pregnancy, fever, infection, wound healing, trauma, tumor, medications

Question 7

Insulin activates what processes

Answer 7

Glycogen synthesis, protein synthesis, fat synthesis

Question 8

Insulin inhibits what processes

Answer 8

Lipolysis, gluconeogenesis

Question 9

Glucagon and epinephrine stimulates what processes

Answer 9

Lipolysis, gluconeogenesis, glycogenolysis

Question 10

Cortisol stimulates what processes

Answer 10

Gluconeogenesis, proteolysis

Question 11

ACTH, CTH, thyroid hormone enhances what process

Answer 11

Lipolysis

Question 12

Elevated glucose levels after a meal enhances ……. by..?

Answer 12

Enhances fatty acid synthesis, by increasing cytoplasmic citrate and NADPH-concentrations, and by providing an alpha-glycerophosphate source

Question 13

Elevated FFA levels during starvation leads to..

Answer 13

Inhibition of cellular glucose uptake and it enhances glycogenolysis and gluconeogenesis

Question 14

Where do we store protein? How many percent of our body mass?

Answer 14

Muscle, 12-17% of body weight

Question 15

Where do we store carbohydrates? How many percent of our body mass?

Answer 15

Liver and muscle as glycogen, blood as sugar. Less than 1 percent of body mass

Question 16

Where do we store fat? How many percent of our body mass?

Answer 16

Stored in adipose tissue, 15-25% of body mass

Question 17

What is the energy source of connective tissue in starvation?

Answer 17

Fatty acids

Question 18

Besides glucose, what is burnt by the brain in adapted (late) starvation?

Answer 18

Ketone bodies

Question 19

Appropriate laboratory test if chronic malnutrition is suspected?

Answer 19

Se Albumin

Question 20

Processes taking place in the postprandial period (0-6 hours after meal)

Answer 20

Protein synthesis, glycogen synthesis, triglyceride synthesis (high insulin/glucagon ratio)

Question 21

Processes taking place in the postabsorption period (6-24 hours after meal)

Answer 21

Glycogenolysis (while stores last), gluconegenesis (liver)

• Glucose consumption in muscle and fat tissue decreases -> uses fat instead
• Ketone body production in the liver

Question 22

Processes taking place in the early, non adapted starvation (1-3 days after meal)

Answer 22

• Glucose source: Gluconeigenesis (liver and renal cortex)
• Glucose consumption: Minimal in muscle, decreases in brain (use of ketone bodies increases)
• Now high level of ketone body production

Question 23

Processes taking place in the late, adapted starvation (>3 days after meal)

Answer 23

• Glucose sourse: Gluconeogenesis
• Glucose consumption: Decreases in the brain (2:1 ratio of ketone bodies to glucose)
  (Always unchanged glucose consumption in RBC and renal medulla)

Question 24

Clinical conditions causing ketosis

Answer 24

Starvation/fasting, untreated diabetes mellitus 1, alcoholism, ketogenic diet, vomiting (mostly in children)

Question 25

What conditions can be treated with a ketogenic diet?

Answer 25

Certain epileptic conditions, and its also a way of loosing weight

Question 26

2 diseases caused by insufficient protein intake in childhood

Answer 26

Kwashiorkor, Marasmus

Question 27

Three criteria for suspicion of malnutrition

Answer 27

• 10% unwanted weight loss in 3 months
• Body mass <90% of ideal
• BMI <18,5 kg/m2

Question 28

Definition of cachexia

Answer 28

Significant weight loss caused by certain conditions, where the decrease of body mass cannot be explained by the decreased calorie intake alone. It affects mostly the muscle mass

Question 29

During cachexia, the ubiquitin-proteasome system is activated. What are its components?

Answer 29

Inflammatory mediators: TNFalpha, IL-6, IL-1beta

Mediators produced by the tumor: Proteolysis inducing factor (PIF)

Question 30

Most important peptide synthesized in adipose tissue that affects food intake?

Answer 30

Leptin

Question 31

A complication of the respiratory system in obesity?

Answer 31

Pickwick syndrome

Question 32

Hormone stimulating lipogenesis?

Answer 32

Insulin

Question 33

If we have an increase in adipose tissue, leptin levels will… and lead to…?

Answer 33

Leptin levels will rise -> decreased food intake, increased energy expenditure, sympathetic activity increased