Anti-oxidant and anti-apoptotic effects of luteolin on mice peritoneal macrophages stimulated by angiotensin II. 
Luteolin, a plant flavonoid, can be found in a variety of plants and possesses anti-tumorigenic, anti-mutagenic, anti-oxidant and anti-inflammatory properties.  However, the protective effects of luteolin on mice peritoneal macrophages stimulated by Angiotensin II (Ang II) have not been fully elucidated.  Mice peritoneal macrophages were confirmed to be strongly positive for the macrophage marker CD68.  Cell viability was tested after cells were pretreated with different concentrations of luteolin (6.25, 12.5 and 25μM) and stimulated by Ang II.  Luteolin not only significantly increased the viability of macrophages in the presence of Ang II, but also decreased the apoptotic rate, up-regulated Bcl-2 expression, and down-regulated Bax expression, thereby raising the ratio of Bcl-2 to Bax.  In addition, luteolin pretreatment significantly increased the activity of SOD and reduced the levels of malondialdehyde (MDA), which was up-regulated in the presence of Ang II.  This protective effect was also seen with Vitamin E (VitE) pretreatment, which was used as a standard control in this study.  These data clearly demonstrate that luteolin suppresses Ang II-directed oxidative stress and apoptosis on mice peritoneal macrophages.