Retinal Pigment Epithelial Cell Damage by Exposure to Benzo[a]pyrene

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Retinal Pigment Epithelial Cell Damage by
Exposure to Benzoapyrene

• Presented by Nathaniel Houston II
• Patton,W.P., M. Routledge, G. Jones, S. Lewis, D.
  Archer, J. Davies, and U. Chakravarthy. 2002.
  Retinal pigment epithelial cell DNA is damaged by
  exposure to benzoapyrene, a constituent of
  cigarette smoke. Exp. Eye Res. 74513-522

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Importance of RPE Cells

• Maintenance of outer blood retinal barrier
• Transport nutrients to outer retina
• Phagocytosis of shed photoreceptor outer segments
• Antioxidant free radical scavenging activities

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The Eye

• 1 optic nerve, 2 blind spot, 3 fovea, 4
  sclera, 5 choroid,
• 6 retina, 7 ciliary body, 8 posterior chamber,
  9 anterior chamber, 10 cornea, 11 lens, 12 iris,
  13 suspensory ligament, 14 conjunctiva, 15
  vitreous body

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Polycyclic Aromatic Compounds

• Known to cause..
• Metabolic changes in the uvea
• Induce more production of drug metabolizing
  enzymes (DMEs)
• Ex. Benzoapyrene, a xenobiotic

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How Do Polycyclic Aromatic Compounds Work?

• ITS ALL ABOUT THE HYDROGENS!!!
• An enzyme activates Hs (DMEs)
• Hs become highly electrophilic
• Hs bind to DNA, proteins, other vital molecules

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Experiments Performed

• Effects of Benzoapyrene on retinal cell growth
• Effects of Benzoapyrene on retinal cells
  ability to reflect UV waves

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Effects of Benzoapyrene on Retinal Cell
Growth

• A Untreated RPE cells (control)
• B RPE cells treated w/ 100 um BaP for 5 days
• C RPE cells treated w/ 100 um BaP for 10 days

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Effects of Benzoapyrene on Retinal Cells
Ability to Reflect UV Waves

• A Untreated RPE cells exposed to .0009 J cm UVB
  (control)
• B RPE cells treated w/ BaP for 5 days exposed
  to same conditions

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In Conclusion

• If you dont want.
• Early macular degeneration
• Apoptosis
• Uncontrollable eyeball growth w/ tumors
• Overall blindness
• Tell your peers to blow their smoke
• in a different direction!!

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THE END