I've always thought I was over-high in nitric oxide, and I have tried lutein and, so far, I think it does reduce nitric oxide levels. This causes a more relaxed , less tense feel. I need to retry this for a while to confirm, but so far lutein does feel like it acts as below

Lutein Acts as Anti-Inflammatory Nutrient
Breaking News
VRP Staff

Researchers at Rutgers University have uncovered the mechanism of action whereby the carotenoid lutein acts as an anti-inflammatory nutrient.

Although a number of in vivo studies have demonstrated the anti-inflammatory effect of lutein, its in vitro anti-inflammatory molecular mechanism of action has not previously been studied. In the current study, researchers investigated the in vitro anti-inflammatory effect of lutein using a mouse macrophage cell line. The researchers stimulated the production of nitric oxide in the cells and then treated the cells with lutein. Lutein decreased the nitric oxide production by 50 percent and decreased other factors that contribute to nitric oxide production by 72.5 percent.

Although nitric oxide is best known as a dilator of blood vessels and plays a role in enhanced sexual response, nitric oxide also is generated by macrophages and neutrophils as part of the human immune response. When nitric oxide is elevated it can signal that macrophages are instigating an attack on foreign antigens. This elevation in nitric oxide is indicative of an inflammatory response that the body is launching to help eliminate the pathogens. When the researchers in the study above triggered excessive production of nitric oxide in the macrophages, they were essentially delivering too much of a good thing in order to elicit an inflammatory response. Lowering the levels of excessive nitric oxide produced in this experiment was therefore an indication of reduced inflammation.

The researchers concluded that it is lutein’s ability to influence nitric oxide production that is responsible for its anti-inflammatory actions.

Reference:
Rafi MM, Shafaie Y. Dietary lutein modulates inducible nitric oxide synthase (iNOS) gene and protein expression in mouse macrophage cells (RAW 264.7) Molecular Nutrition & Food Research. 5 March 2007;51(3):333-340.