Hormone Disruption

1
Hormone Disruption

• Diethylstilbesterol
• Evidence in Animals
• Evidence in Humans
• Sources of EDs
• Synergies?

2
Diethylstilbesterol

• Synthetic estrogen (1938)
• Stimulates ovulation
• Reduces miscarriages
• Morning after pill
• Livestock feed
• Slows teenage growth
• Cancer in daughters
• Reprod. problems in sons

3
Animal Effects

• Enlarge fish thyroids
• Masculinized female fins
• Reproductive failure in Lake Apopka alligators

4
Animal Effects

• Birds of prey deformities
• Gull pair bonding
• Mink reprod. Failure
• Florida Panther problems

5
Animal Effects

• Worldwide amphibian decline
• Deformed frogs
• Trematodes?
• Injury?
• UV radiation?
• Endocrine disrupters?
• Methoprene?

6
Methoprene breaks down in UV and mimics retinoic
acidLaClair et al. 1998
Spinal curvature as juveniles
Eye malformations as adults
7
Human Effects
8
Human Effects?

• Declining sperm counts?
• Undescended testes
• Incomplete closure of penis
• Testicular cancer
• All can be induced in male rats by fetal exposure
  to DES

9
Human Effects?

• Prostate cancer
• Accelerated puberty
• Compromised immune system?

10
Sources of Endocrine Disrupters

• Chlorinated hydrocarbons
• DDT, PCBs
• Some heavy metals
• Contraceptives
• Plasticizers
• Nonylphenols,
• Bisphenol A

11
Hormone-Receptor Interactions

• Normal interactions
• Hormone mimics blockers
• Role of serum binding proteins
• eg DES has less affinity for serum proteins,
  thus has greater cellular activity