Starvation

Question 1

What are some lifelong impacts of malnutrition?

Answer 1

Increased vulnerability to disease, developmental delays, stunted growth, and blindness.

Question 2

Malnutrition

Answer 2

often associated with starvation , but can have a specific nutritional deficiency or excess

Question 3

Starvation

Answer 3

in elderly that don’t receive nutrition, chronically ill patients, and those affected by trauma or infection

Question 4

What are the metabolic functions of liver in fed state?

Answer 4

uptakes glucose via GLUT 2 and converts excess glucose to glycogen. It also produces Acetyl CoA for TG storage via VLDL that goes into circulation, and synthesizes proteins from excess AAs.

Question 5

What do other tissues outside of the liver do during the fed state?

Answer 5

Glucose is main source of energy so adipose stores TGs, brain uses glucose, RBCs use glucose, and muscles take up via GLUT4, stores as excess glycogen or makes proteins from excess AA.

Question 6

How is blood glucose maintained in the Basal/ Post Absorptive state?

Answer 6

Blood glucose peaks 1hr after a meal and returns to fasting 2hrs later. After, liver maintains glucose through glycogenolysis until depleted. After depletion, liver does gluconeogenesis via lactate, glycerol, AA. FA are main fuel source. Muscles use glycogen, FA, KB. Brain and RBCs use glucose.

Question 7

What are liver, muscle, adipose, brain, RBCs, and kidney using as energy during prolonged fasting?

Answer 7

Liver is barely doing gluconeogenesis by making fatty acids into ketone bodies. Muscle decreases its use of glucose and increases use of FAs. Uses KBs for a brief moment, but begins decreasing AA so liver can do gluconeogenesis for brain. This decreases urea production, Adipose continues making FAs and glycerol. Brain begins using more KBs (exclusively KB after 2 weeks). RBCs use glucose for anaerobic glycolysis. Kidney secretes less urine.

Question 8

What decreases compared to fasting for 24 hrs to prolonged fasting?

Answer 8

urea production, muscle degradation, liver gluconeogenesis, brain use of glucose, and muscle use of ketone bodies all decrease

Question 9

which tissues can perform beta oxidation?

Answer 9

Liver, kidney, muscle

Question 10

which tissues can form KBs?

Answer 10

Liver and kidney

Question 11

which tissues can perform lipogenesis?

Answer 11

liver and adipose

Question 12

Nitrogen equilibrium vs. positive balance vs. negative balance

Answer 12

Equilibrium is when nitrogen intake = excretion, positive balance = nitrogen intake > excretion, and negative balance = nitrogen intake < excretion (starvation, trauma, cancer)

Question 13

Pathological adaption

Answer 13

Metabolic changes to restore nitrogen equilibrium at expense of some lean tissue

Question 14

Minimum protein requirement

Answer 14

Amount of protein in person’s diet below which they cannot re-establish a nitrogen balance with normal diet

Question 15

What’s immediate response to starvation?

Answer 15

proteolysis of skeletal muscle to increase AA catabolism

Question 16

What’s prolonged starvation response?

Answer 16

low insulin increases muscle proteolysis to maintain nitrogen. This large loss of muscle and urea is adapted to after a few days and you lose less muscle because the goal of starvation is to reduce free AAs

Question 17

How do you die from starvation and what are determining factors?

Answer 17

you die when you lose about 40% of your body weight. Factors determining survival are starting adipose tissue levels, protein levels, vitamin/mineral precursors, and electrolyte composition.

Question 18

Diabetes Mellitus

Answer 18

Metabolic disorder characterized by an elevated fasting blood glucose caused by a relative or absolute deficiency in insulin.

Question 19

Type 1 diabetes

Answer 19

hyperglycemia, an absolute deficiency in insulin caused by an autoimmune attack against the beta pancreatic cells

Question 20

Type 2 diabetes

Answer 20

hyperglycemia due to insulin resistance, impaired insulin secretion, and dysfunctional beta cells

Question 21

What’s happening in metabolism of patient with diabetes?

Answer 21

There’s impaired glucose uptake because tissues can’t use it. Liver increases glycogenolysis, increases gluconeogenesis by making FAs into KBs. Adipose increases mobilization of TGs for lipolysis to release FFAs to liver. Muscle increases glycogenolysis and gluconeogenic precursors. Kidney makes KBs.

Question 22

Cachexia

Answer 22

metabolic syndrome associated with chronic diseases like kidney disease, pulmonary disease, advanced cancer, AIDs. Characterized by decreased skeletal muscle without fat mass loss. This is caused by release of pro-inflammatories like TNFa, Il-1, Il-6, and IFNy that activate ubiquitin pathway.

Question 23

What are clinical presentations of cachexia?

Answer 23

weight loss, fatigue, decreased skeletal muscle, anemia, atrophic diaphragm, increased hepatic protein synthesis

Question 24

Anorexia nervosa

Answer 24

Self starvation. Clinical presentations: dehydration, electrolyte imbalance, low LSH, low thyroid hormone (cold), constipation, dry skin, osteoporosis, anemia, and hypalbuminemia

Question 25

Marasmus

Answer 25

Prolonged protein energy malnutrition due to caloric insufficiency. Weight decreases below 60%. There is low leptin produced so this stimulates cortisol production which leads to lipolysis

Question 26

What are clinical presentations of Marasmus?

Answer 26

muscle wasting, growth retardation, anemia, immune deficiency, albumin is normal, diarrhea, and MISC which progresses to cardiovascular problems or rickets

Question 27

Kwashiorkor

Answer 27

protein malnutrition but not in calories. Seen in children who weaned too early, people with chronic diarrhea, people of fad diets, and people who drink rice beverages.

Question 28

What are clinical presentations of Kwashiorkor?

Answer 28

Edema, hypoalbuminemia, puffy face/extremities, abdominal distention, hepatomegaly, diarrhea, loss of appetite, hair color loss, dry lesioning skin.

Question 29

True or False: Marasmus is more chronic and Kwashiorkor is more acute?

Answer 29

true