Hydroxytyrosol (HT) is the major o-diphenol present in extra-virgin olive oil, either in free or esterified form, once absorbed, is present in high amount in the kidney, where it may exert a proctetive action. In this study we monitored the ability of HT to protect renal cells (LLC-PK1) against oxidative damage induced by H2O2. The peroxidation of lipid represents a primary consequences of cellular oxidative stress, leading to biophysical changes that disrupt membrane and organelle function; moreover oxidative stress is a process that may stimulate cellular signalling pathways, usually associated with the promotion of cellular death. HT exerted a significant antioxidant action, inhibiting the production of fatty acids hydroperoxides and 7-ketocholesterol induced by H2O2 treatment and thus preserving the membrane lipids. It has been shown that oxidative stress in LLC-PK1 cells is related also to the changes in the phosphorylation state of pro-death signalling pathways ERK1/2 and the pro-survival signalling Akt/PKB. Pretreatment with HT is able to modulate H2O2-induced changes in the phosphorylation state of ERK1/2 and Akt/PKB. We suggest that one potential protective mechanism of olive oil polyphenols in kidney cells may be attributed to interactions with intracellular signalling pathways activated in response to oxidative stress.
H2O2 oxidative activity: modulatory effect of hydroxytyrosol
INCANI, ALESSANDRA;DEIANA, MONICA;Melis MP;ROSA, ANTONELLA;
2012-01-01
Abstract
Hydroxytyrosol (HT) is the major o-diphenol present in extra-virgin olive oil, either in free or esterified form, once absorbed, is present in high amount in the kidney, where it may exert a proctetive action. In this study we monitored the ability of HT to protect renal cells (LLC-PK1) against oxidative damage induced by H2O2. The peroxidation of lipid represents a primary consequences of cellular oxidative stress, leading to biophysical changes that disrupt membrane and organelle function; moreover oxidative stress is a process that may stimulate cellular signalling pathways, usually associated with the promotion of cellular death. HT exerted a significant antioxidant action, inhibiting the production of fatty acids hydroperoxides and 7-ketocholesterol induced by H2O2 treatment and thus preserving the membrane lipids. It has been shown that oxidative stress in LLC-PK1 cells is related also to the changes in the phosphorylation state of pro-death signalling pathways ERK1/2 and the pro-survival signalling Akt/PKB. Pretreatment with HT is able to modulate H2O2-induced changes in the phosphorylation state of ERK1/2 and Akt/PKB. We suggest that one potential protective mechanism of olive oil polyphenols in kidney cells may be attributed to interactions with intracellular signalling pathways activated in response to oxidative stress.
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
