The polysaccharide from Tamarindus indica (TS-polysaccharide) protects cultured corneal-derived cells (SIRC cells) from ultraviolet rays.
The aim of this work was to investigate the possible protective effect of a new viscosising agent, TS-polysaccharide, on corneal-derived cells (SIRC) exposed to ultraviolet-B rays. To verify this, SIRC cells were first exposed, in the absence or in the presence of TS-polysaccharide (1% w/v), for 9 s at the UV-B source and then post-incubated for 45 min at 37 degrees C. After this period the hydrogen peroxide (H(2)O(2)) accumulated in the medium and the concentration of 8-hydroxy-2'-deoxy-guanosine (8-OHdG) in cell DNA was measured. In addition, the amount of (3)H-methyl-thymidine incorporated in cellular DNA was evaluated after 18 h from irradiation. Our results show that cells exposed to UV-B rays accumulate H(2)O(2), and have higher levels of 8OHdG and a lower amount of (3)H-methyl-thymidine incorporated in DNA than control cells. In the presence of TS-polysaccharide, the H(2)O(2) and 8-OHdG accumulation, and the (3)H-methyl-thymidine incorporation were significantly reduced with respect to the values measured in cells exposed in the absence of the polysaccharide. We propose a protective role of the polysaccharide in reducing UV-B derived DNA damage to eye cells. This finding could be of some clinical importance when the polysaccharide is used as a delivery system for ophthalmic preparations.
Raimondi
L
L
Dept. of Pharmacology, University of Florence, Italy. laura.raimondi@unifi.it
Lodovici
M
M
Guglielmi
F
F
Banchelli
G
G
Ciuffi
M
M
Boldrini
E
E
Pirisino
R
R
D000080242:8-Hydroxy-2'-Deoxyguanosine; D000818:Animals; D002478:Cells, Cultured; D003315:Cornea / Q000166:cytology / Q000187:drug effects* / Q000528:radiation effects*; D003470:Culture Media; D004247:DNA / Q000187:drug effects / Q000528:radiation effects; D003849:Deoxyguanosine / Q000031:analogs & derivatives* / Q000378:metabolism; D005136:Eye Proteins / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D010084:Oxidation-Reduction; D011134:Polysaccharides / Q000302:isolation & purification / Q000494:pharmacology*; D011817:Rabbits; D011837:Radiation-Protective Agents / Q000302:isolation & purification / Q000494:pharmacology*; D029861:Tamarindus / Q000737:chemistry*; D013936:Thymidine / Q000031:analogs & derivatives* / Q000378:metabolism; D014466:Ultraviolet Rays
D003470:Culture Media; D005136:Eye Proteins; D011134:Polysaccharides; D011837:Radiation-Protective Agents; D000080242:8-Hydroxy-2'-Deoxyguanosine; D004247:DNA; C012439:methylthymidine; D006861:Hydrogen Peroxide; D003849:Deoxyguanosine; D013936:Thymidine