Endocrine Distruptors

Question 1

what are endocrine distruptors

Answer 1

chemicals that can have negative health effects

Question 2

why do you need a healthy endocrine system

Answer 2

important to reproduce and develop normally

Question 3

endocrine distruptors

Answer 3

any exogenous chemicals that interferes with the production, release, transport, binding, action or elimination of natural hormones responsible for the maintenance of homeostasis and regulation of developmental processes

Question 4

endocrine modulator

Answer 4

xenobiotic compound with hormone-mimetic property
structures of the molecules are very similar
do not need to match 100% as it can modify structures to fit

Question 5

Modes of EDC action

Answer 5

1. serving as steroid receptor ligands
2. modifying steroid hormone metabolizing enzymes
3. perturbing hypothalamic pituitary release of trophic hormones
4. miscellaneous or unknown
5. interactions with the functions of estrogens, androgens, and thyroid hormones have been the most studied

Question 6

examples of endocrine distruptor chemicals

Answer 6

pesticides
herbicides
fungicides
plasticizers
surfactants
organometals

Question 7

hormones

Answer 7

act via hormone receptors
active at low doses
non linear dose-response relationships
tissue specific effects
life stage specific effects
developmental effects permanent
different end points vary in sensitivity

Question 8

endocrine disruptor aspects

Answer 8

• some act via hormone receptors and multiple receptors
• some act at low doses, others variable
• non linear dose response relationships
• tissue and life stage specific effects

Question 9

timing of exposure

Answer 9

critical factor

• during ‘programming’ = permanent changes
• during adulthood = homeostasis, no effects
• at same level during different stages of life = diff effects
• timing will determine nature and severity of effects

Question 10

hormone action

Answer 10

can effect multiple different factors

key is similar to many receptors

Question 11

steroid receptors

Answer 11

androgen
progesterone
glucocorticoid
mineralocorticoid

Question 12

thyroid receptors

Answer 12

thyroid hormone
retinoic acid
RXR
vitamin D

Question 13

mechanisms of endocrine disruption

Answer 13

• Binding and activating the estrogen receptor (thereby acting as an estrogen)
• Binding but not activating the estrogen receptor (thereby acting as an anti-estrogen)
• Binding other receptors (e.g., androgen receptors in males)
  Activating the receptor thereby acting like an androgen
  Not activating the receptor thereby acting like an anti-androgen
• Modifying metabolism, production and number of receptors for natural hormones