Obesity Flashcards
What is WAT
White Adipose Tissue
contributes to the regulation of energy homeostasis by secretion of adipokines that function like hormones with autocrine, paracrine, and endocrine actions necessary for metabolic function and immune responses.
List the characteristics of WAT
located in visceral (central) and subcutaneous (peripheral) stores
found in muscle groups providing mechanical protection and sliding of muscle bundles, and bone marrow
contains macrophages, mast cells, neutrophils, fibroblasts, endothelial cells, blood vessels, nerves, and precursor adipocytes.
How is Brown Adipose Tissue stimulated?
Exposure to cold
activation of the sympathetic nervous system and catecholamines
activation of triiodothyronine (T3)
Why is BAT brown?
It is rich in mitochondria that contain iron, giving them a brown color.
Where is BAT found?
In adults, it is located in the neck, supraclavicular, axillary, paravertebral, and perirenal regions
In neonates, interscapular and perirenal regions
With hormone changes in middle age, how is adipose deposited differently between the two genders?
Women carry more adipose peripherally, and men carry adipose viscerally.
How do hormones affect obesity in perimenopause?
Estradiol increases α2-adrenergic receptors in subcutaneous adipose tissue but not in visceral adipose tissue.
What is the role of BAT?
To generate body heat
What process protects against obesity and metabolic syndrome?
“beiging” or “browning” of adipose tissue
Obesity
caloric intake exceeds caloric expenditure in genetically susceptible individuals.
body mass index (BMI) that exceeds 30 kg/m2 in adults
BMI greater than or equal to the age- and sex-specific 95th percentile in children
Metabolic abnormalities contributing to obesity
Cushing syndrome/Cushing disease,
polycystic ovary syndrome,
growth hormone deficiency
hypothyroidism
hypothalamic injury
Environmental factors contributing to obesity
socioeconomic status (both high and low
incomes)
food intake (low-nutrient, energy-dense foods)
physical inactivity
Describe the pathophysiology of obesity
Visceral WAT accumulation interferes with the regulation of the signaling system that tells your brain that you are full
What endocrine organ has the greatest effect on obesity?
the hypothalamus
How does the hypothalamus play a role in food intake and energy use?
communicates with higher brain centers related to reward, pleasure, memory, and addictive behavior
manage the neurons that promote and suppress appetite, stimulate and suppress eating, and increase and decrease metabolism
