Hydrophobic Molecules of Life

1
Hydrophobic Molecules of Life

• Lipids 2

2
Sterols

• Cholesterol (and stigmasterol, ergosterol)
  modifies liquidity of membranes
• Tends to make paracrystalline phase more liquid,
  liquid phase more viscous
• Evidently not essential for life (Mice)
• Biologically active lipid molecules
• Hormones (glucocorticoids, androgens, estrogens,
  progesterone)
• bile acids

3
Fig 11-17
4
Eicosanoids

• 20 carbon compounds from arachidonic acid
  (204(?5.8,11,14))
• Prostaglandins
• Regulate 3,5-cyclic AMP
• Thromboxanes
• Clotting
• Leukotrienes
• Various
• Hormonal signal triggers cleavage from membrane
  (phospholipase A2)

5
Fig 11-16
6
Fig 21-16
7
COX-2 inhibitors

• Celecoxib (Celebrex, Pharmacia) and Rofecoxib
  (Vioxx, Merck) inhibit the cyclooxygenase
  activity which regulates inflammation, pain and
  fever selectively.
• NSAIDS (aspirin, ibuprofen, naproxen,
  acetaminophen) inhibit the activities of COX-1
  (secretion of gastric mucin) and COX-2 about
  equally.

8
Fat SolubleVitamins

• A (retinol)
• D (cholecalciferol)
• E (Tocopherol)
• K (quinones)

9
Fig 11-19
10
Fig 11-18
11
Fig 11-20 a
12
Fig 11-20 b
13
Fig 11-20 c
n 7-9