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Flashcards in EDCs Deck (62):
1

What is the most important gland?

The hypothalamus

2

Define hormone

a signaling molecule that regulates physiology and behaviour

3

Name 5 types of hormones

peptide, steroid, eicosanoid, amine, and glycoprotein

4

Peptide hormones

derived from amino acids, insulin

5

Steroid hormones

derived from cholesterol, testosterone

6

Eicosanoid hormones

derived from lipids, prostaglandin

7

Amine hormones

derived from the amino acid tyrosine; two categories: catecholamine (epinephrine) and thyroid hormones (T3)

8

Catecholamine hormones

category of amine hormones, epinephrine

9

Thyroid hormones

category of amine hormones, T3

10

Glycoprotein hormones

derived from amino acids with carbohydrate side chains, FSH

11

Hormones vs. NTs

H: large spatial and temporal scales, slow transmissions w/ continuously variable action, specific receptors NT: small scale, quick transmission, all-or-nothing action

12

Name the axis that controls the development and regulation of reproductive and immune systems

the hypothalamus-pituitary-gonadal axis

13

Walk through the HPG axis

the brain releases gonadotropin-releasing hormone (GnRH) to anterior pituitary which releases LH and FSH. these cause ovaries to make estrogen and progesterone. they cause testes to produce testosterone

14

Name the axis that VTG works on

the hypothalamus-pituitary-gonadal-liver axis

15

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Estradiol

16

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BPA

17

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Bis(2-ethylhexyl) phthalate (DEHP)

18

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Nonylphenol

19

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p,p-DDE

20

What is the ligand-activated transcription factor of estradiol?

the estrogen receptor

21

What is the ligand-activated transcription factor of cortisol

the glucocorticoid receptor

22

What is the ligand-activated transcription factor of all-trans-retinoic acid?

Retinoic acid receptor

23

What is the ligand-activated transcription factor of fatty acids?

peroxisome proliferator-activated receptor

24

What is the ligand-activated transcription factor of androstenol

contitutive androstane receptor

25

What is the ligand-activated transcription factor of pregnolone and progesterone

pregnane X receptor

26

What is the endogenous ligand of ER

estradiol

27

What is the endogenous ligand of glucocorticoid receptor

cortisol

28

What is the endogenous ligand of retinoic acid receptor?

all-trans-retinoic acid

29

What is the endogenous ligand of aryl hydrocarbon receptor

it is unknown

30

What is the endogenous ligand of PPARa

fatty acids

31

What is the endogenous ligand of constitutive androstane receptor

androstenol

32

What is the endogenous ligand of pregane X receptor

pregnenolone and progesterone

33

Walk through the HPGL axis in oviparous organisms

GnRH tells anterior pituitary to release GTHI and GTHII which tell the gonads to tell E2 to tell the liver to make VTG and ZRP and go to the gonads, which then send E2 to teh hypothalamus 

34

What is the name of the nervous system in invertebrates?

Neuropil

35

what are the four main targtes of EDCs?

  1. hormone synthesis
  2. hormone transport
  3. hormone degradation
  4. hormone action 

36

hormone syntheis as a target

big target is steroidogensis. the rate limiting step in steroidogensis is the conversion of cholestrol to pregnenolone by Steroidogenesis Acute Regulatory Protein. all other steroids are derived from pregnenolone

37

Name three "transport proteins" that are for hormones

corticosteroid-binding globulin (CBG)

sex-steroid binding globulin (SSBG)

thyroxine-binding globulin

38

EDCs tend to interact with hormones that bind with what kind of receptors?

nuclear receptors

39

Where on nuclear receptors do hormones bind?

the ligand binding domain

40

what does E2 aid in in vertebrates

reproduction, the cardiovascular system, bones, indirectly aid thyroid hormone action 

41

What is the purpose of Tier I assays?

Name three tier I systems

they evalute whether the substance has the potential to interact with the hormone system 

  1. ER competitive binding assay
  2. yeast reporter gene assay
  3. E-SCREEN assay

42

What are the limitation of Tier I assays?

they focus on receptor-mediated effects, but some EDC cause non-receptor-mediated effects. they could alter enzyme activity, change transduction pathways...

43

What is so special about the H295R Steroidogenesis Assay?

it can detect non-receptor mediated effects and you don't have to kill whole animals to run it

44

What is the purpose of Tier II assays?

What are three types?

they confirm endocrine distrupting effects and dose-response info to be used for risk assessment

  1. mouse uterotropic assay
  2. full life cycle tests
  3. two-generation reproductive toxicity tests

45

What is the jost paradigm of sexual differentiation

Sexual differentiation can be viewed as a sequential process beginning at the moment of conception when chromosomal sex is established. the gonads then differentiate into ovaries or testes, and the consequence of this gonadal differentiation is binary sexual phentype development

46

In things like birds, mammals, and amphibians, what are the dependent factor of sexual determination

genetics

47

in reptiles, what factor controls sexual determination?

temperature

48

Define sexual differentiation

the embryonic process of developing into a male or female 

49

The Y chromosome causes the expression of what gene that initiates male development?

The SRY gene

50

Before sexual determination, the gential ridge must on a bipotenial gland called the _____? What does it develop into in males and in females?

Mesonephros: testes and ovaries

51

what the word for undescended testicles?

chryptochidism

52

whats the word for when the urethra develops on the underside of the penis?

hypospadias

53

What was the main adverse effect of DES

organogenesis exposure disrupting differentiation of estrogen responsive organs, led to vaginal and cervical clear cell adenocarcinoma

54

Where does DES bind?

the alpha estrogen receptor in utero 

55

talk about gene imprinting

DES does this, it's an epigenetic response, DNA methylation alters transcription, histone modification alters chromatin structure, thus altering gene expression 

56

does DES or E2 have stronger binding affinity for sex-steroid hormone binding globulin? what are the implications of this?

E2 does. so that means DES will be unbound extracellularly, thus more bioavailable and capable of passing intracellularly

57

What is EE2

17 alpha-ethinylestradiol is a potent synthetic estrogen used in oral contraceptives 

58

what is BPA

bisphenol-a is a monomer of plastics (#7, baby bottles, dental devices), structurally similar to DES, weak ER agonist, much weaker than E2

59

what are the four main low dose chronic processes of concern causing BPA exposure?

  1. hot coffee epoxy resins
  2. microwaving plastics
  3. chewing toys for dogs, babies
  4. canned goods lined with epoxy resin/things stored in plastic

60

phthalates are agonists of what receptor?

peroxisome proliferator-activated receptor-alpha, a nuclear receptor abundant in the liver, regulates cell differentiation, functionally inactive in primates 

61

what is the most commonly used alkylphenol, and what is the name of its dangerous degradation product

nonylphenol polyethoxylate, and nonylphenol

62

NPs are in waterway at pg/L levels, why do we care?

because they are lipophilic and have high bioconcentration factors. affect aquatic species' seual development, differentitation and reproduction