SM_191b: Starvation and Metabolic Adaptation Flashcards
Starvation is ___
Starvation is physiologic state of negative energy ± protein balance
Starvation-associated malnutrition or protein energy malnutrition is ___
Starvation-associated malnutrition or protein energy malnutrition is prolonged deficit of energy and/or protein, which results in clinical manifestations
Disease associated malnutrition (cachexia) occurs with ___, is characterized by ___, and is induced by ___
Disease associated malnutrition (cachexia) occurs with illness, is characterized by increased protein catabolism, and is induced by inflammatory cytokines
Caloric restriction is ___
Caloric restriction is volitional reduction in energy intake (below needs), with adequate intake of protein and micronutrients
Sarcopenia is ___
Sarcopenia is loss of muscle mass associated with aging
Total energy expenditure = ____ + ____ + ____
Total energy expenditure = basal metabolic rate + thermic effect of food + energy expenditure of physical activity
(TEE = BMR + TEF + EEPA)
Total energy expenditure (TEE) is ___
Total energy expenditure (TEE) is energy expended by an individual in one day
Basal metabolic rate is ____
Basal metabolic rate is energy expended for vegetative functions of the body (respiration, body temperature regulation, etc)
Thermic effect of food is ___
Thermic effect of food is increase in energy expenditure observed after the consumption of a meal
Energy expenditure of physical activity is ____
Energy expenditure of physical activity is energy used during daily physical activity (exercise + non-exercise)
Total energy expenditure consists of ____, ____, and ____
Total energy expenditure consists of basal metabolic rate (60%), energy expenditure of physical activity (30%), and thermic effect of food (10%)
Determinants of basal metabolic rate are ___, ___, ___, ___, and ___
Determinants of basal metabolic rate are body composition, age, gender, nutritional status, and health status
Most usable energy stores are ____
Most usable energy stores are fatty acids
(then protein, then glycogen)
Fuel metabolism during starvation first involves ____, then ____, then ____
Fuel metabolism during starvation first involves exogenous, then glycogen, the gluconeogenesis
During starvation, origins of new blood glucose are ___ and ___
During starvation, origins of new blood glucose are liver (50-80%) and kidneys (20-50%)
During starvation, substrates for gluconeogenesis are ____, ____, ____, ____, and ____
During starvation, substrates for gluconeogenesis are lactate, pyruvate, alanine, glycerol, and glutamine (used by kidney)
During starvation, other fuel sources are ____ and ____
During starvation, other fuel sources are free fatty acids and ketone bodies
In fuel usage by tissue (late starvation), brain mainly uses ____
In fuel usage by tissue (late starvation), brain mainly uses ketone bodies
Describe changes in energy expenditure during starvation
Changes in energy expenditure during starvation
- TEE: decreased
- BMR: decreased
- TEF: decreased
- EEPA: decreased
Ghrelin and glucagon ____ during starvation
Ghrelin and glucagon increase during starvation
Leptin, insulin, T3 / T4, LH, FSH, estrogen, and testosterone ___ during starvation
Leptin, insulin, T3 / T4, LH, FSH, estrogen, and testosterone decrease during starvation
____ occurs after weight loss
Metabolic adaptation occurs after weight loss
During weight loss in obesity, ____, ____, and ____ are decreased
During weight loss in obesity, leptin, energy expenditure, and T3 / T4 are decreased
During weight loss in obesity, ____ and ____ are increased
During weight loss in obesity, ghrelin and muscular efficiency are increased
____ is modified after weight loss in obesity
Neural activity on brain fMRI in response to visual food cues is modified after weight loss in obesity
After weight loss, gap between ____ and ____ is wider
After weight loss, gap between increased hunger and decreased energy expenditure is wider
Describe metabolic and hormonal changes of weight loss in obesity that are reversed with leptin
Reversed with leptin?
Deecreased
- Leptin: yes
- Energy expenditure: yes
- T3 and T4: yes
Increased
- Ghrelin: no
- Muscular efficiency
Modified
- Neural activity on brain fMRI in response to visual food cues: yes
Metabolic adaptation to weight loss ___ long-term persistence
Metabolic adaptation to weight loss has long-term persistence
Describe metabolic responses to starvation
Metabolic responses to starvation
- Decreased energy expenditure
- Use of alternative fuelds (free fatty acids and ketone bodies) can reduce protein catabolism
- Intake of minimal dietary carbohydrate (100 g) can suppress protein catabolism and gluconeogenesis
Describe metabolic responses to illness
Metabolic responses to illness
- Increased energy expenditure
- Markedly increased protein catabolism
- Glucose does not suppress protein catabolism
In illness, basal metabolic rate ____ due to ____, ____, and ____
In illness, basal metabolic rate increases due to catecholamine / sympathetic nervous system stimulation, fever, and inflammation / cytokines
(BMR may increase by 30-100%)
In illness, protein catabolism ____ due to ____, ____, and ____
In illness, protein catabolism increases due to inflammation and cytokines, increased cortisol, and insulin resistance
Which increases protein catabolism the most?
A. Sepsis
B. Hysterectomy
C. Hip fracture
D. Major burn
E. Starvation
Which increases protein catabolism the most?
A. Sepsis
B. Hysterectomy
C. Hip fracture
D. Major burn
E. Starvation
____ and ____ cause malnutrition
Starvation and disease cause malnutrition
Marasmus involves a deficit of ____
Marasmus involves a deficit of calories
Describe marasmus
Marasmus: deficit of calories
- Very low body weight
- Wasted appearance with loss of muscle and fat
- Liver function is usually normal
- ± hypoalbuminemia
- Dry, inelastic skin
Kwashiorkor involves a deficit of ____
Kwashiorkor involves a deficit of protein
Descrube kwashiorkor
Kwashiorkor: deficit of protein
- Low or normal body weight
- Edema may mask weight loss
- Distended abdomen
- Fatty liver / liver dysfunction
- Marked hypoalbuminemia
- Skin and hair changes
Flag sign, flaky pain rash, and depigmentation of hair occur in ___
Flag sign, flaky pain rash, and depigmentation of hair occur in kwashiorkor
(flag sign: alternating areas of hypo and hyperpigmentation of hair)
8 month old infant fed on demand with rice, milk, bananas, and sweet potatoes for the past 4 months may have ___, ___, ___, and ___
8 month old infant fed on demand with rice, milk, bananas, and sweet potatoes for the past 4 months may have normal body weight, edema, ascites, and desquamative rash
Pathogenesis of kwashiorkor may involve ____, ____, and ____
Pathogenesis of kwashiorkor may involve primary protein deficiency, inadequate antioxidant capacity, and gut microbiome
Malnutrition can result in ___ in childhood
Malnutrition can result in stunted growth in childhood
Describe physiologic changes in malnutrition
Physiologic changes in malnutrition
- Hypothermia
- Cardiovascular: hypotension, bradycardia, and decreased cardiac output
- Pulmonary: decreased respiratory muscle mass and function, decreased respiratory drive
- Endocrine: hypogonadotrophic hypogonadism, osteoporosis
- GI: delayed gastric emptying
- Hematologic: anemia, leukopenia
- Neurologic: decreased volume of gray matter, decreased sympathetic activity
Behavioral changes seen during starvation are ____, ____, ____, ____, and ____
Behavioral changes seen during starvation are
- Preoccupation with food
- Hoarding and stealing food
- Abnormal taste preferences
- Binge eating
- Depression, apathy, irritability, and other personality changes
Oral nutrition involves ____ or ____
Oral nutrition involves whole foods or supplements
Nutrition support to patients who cannot or will not eat involves ____ or ____
Nutrition support to patients who cannot or will not eat involves enteral nutrition or parenteral nutrition
Enteral nutrition is via the ___
Enteral nutrition is via the gut
(if the gut works, use it)
Parenteral nutrition formulas contain ____, ____, ____, and ____
Parenteral nutrition formulas contain water, macronutrients (dextrose, amino acids, emulsified lipids), electrolytes (minerals), and vitamins / trace elemtns
Total parenteral nutrition ___
Total parenteral nutrition meets energy and protein needs
- High osmolality requires administration into vena cava via a central line due to risk of phlebitis
Peripheral parenteral nutrition usually ____
Peripheral parenteral nutrition usually cannot meet energy or protein needs
- Lower osmolality so can be infused through smaller peripheral veins
Refeeding syndrome occurs when ____
Refeeding syndrome occurs when food is introduced too quickly after a period of malnourishment
- Shifts in electrolytes can cause severe complications: seizures, heart failure, and comas
