Luteolin is a bioflavonoid found in many of the same foods that contain apigenin, including celery. While luteolin produces effects similar to apigenin, it has its own unique beneficial properties as well.
Luteolin As An Anti-inflammatory
Like apigenin, luteolin inhibits the effects of epidermal growth factor and tyrosine kinases, and therefore may have potential as an anti-cancer and anti-metastasis agent. When measured against 27 citrus flavonoids, luteolin had the most potent anti-proliferative activities against several tumor and normal human cell lines.(95)
When compared to other flavonoids, only luteolin and quercetin inhibited platelet activating factor and suppressed a type of inflammatory response induced by allergens. The scientists who conducted the study concluded that luteolin could be used to develop a novel type of anti-inflammatory, anti-allergic drugs.(93)
Cancer Fighting Benefits of Luteolin
Luteolin has been shown to arrest cancer growth at the G1 phase of the cell cycle (96). Compared to other flavonoids, luteolin more effectively inhibited proliferation of human leukemia (CEM-C1 and CEM-C7) cells. [source]
Luteolin may help prevent breast and prostate cancer. It has been shown to kill MCF-7 breast cancer cell cultures. Several studies show that luteolin reduces excess estrogen formation by suppressing the aromatase enzyme and blocks the binding of estrogens to breast cell receptor sites.
When a group of plant extracts were evaluated to ascertain if they could maintain normal cell regulation, luteolin demonstrated the highest anti-proliferative activity.(106)
Luteolin Protects Against Free Radicals
Flavonoids are known to protect against radiation-induced free radical damage. In a comparison study, luteolin was found to be the most effective extract in reducing radiation damage to cells. The scientists who conducted the study stated that these plant flavonoids show antioxidative potency in vitro, work as antioxidants in vivo, and their radio-protective effects may be attributed to their scavenging potency towards free radicals.(107)
How Important Are Flavonoids In Protecting Against Cancer?
A human epidemiological study showed a 56% reduction in stomach cancer in those consuming the highest levels of flavonoids compared to the lowest. The results of this study show that the well-established protective effect of fruit and vegetables could, in part, be due to the presence of flavonoids.(108)
When ranked in order of potency, Luteolin was more effective than vitamin C and seven other flavonoids in reducing DNA oxidative damage.