Abstract
Atomic Force Microscopy (AFM) has been used to image membrane surface topography at nanometer resolution. In this study we used the AFM to characterize the physical changes resulting from hyperoxia on cultured human glioblastoma cells (U87). U87 cells were exposed to air (21% O 2 ), hyperoxia (95% O 2 ) or hyperbaric oxygen (HBO 2 , 3.5ata O 2 ) for 30 min. H 2 O 2 (200µM) was used as a positive control. Following treatment, the cells were fixed with 2% glutaraldehyde for 20 min prior to AFM imaging. Three dimensional surface plots of U87 cells revealed a significant distortion of the plasma membrane (membrane blebbing) caused by HBO 2 and H 2 O 2 , which is thought to be indicative of lipid peroxidation. Individual cells from each group were analyzed to assess Mean Roughness (R a ) and Maximum Roughness (R max ). R a was 40 ± 4 nm in 21% O 2 , 52 ± 5 nm in 95%O 2 , 64 ± 7 nm in HBO 2 , and 91 ± 9 nm in H 2 O 2 treated cells. R max was 253 ± 27 nm in 21% O 2 , 302 ± 30 nm in 95% O 2 , 366 ± 35 nm in HBO 2 , and 608 ± 39 nm in H 2 O 2 treated cells. In conclusion, these data show that oxidative damage in the plasma membrane is proportional to oxygen concentration. Moreover, the AFM is capable of characterizing subtle changes in membrane topography from oxidative damage.
| Original language | American English |
|---|---|
| State | Published - Apr 1 2007 |
Disciplines
- Medical Cell Biology
- Medical Neurobiology
- Medical Physiology
- Medical Sciences
- Medicine and Health Sciences
- Neurosciences
- Physiological Processes