NOS2 and Anxiety: On the other hand, isoflavones inhibit inducible nitric oxide synthase (iNOS) and then reduce the production of nitric oxide, which regulates the concentration of neurotransmitters such as serotonin, dopamine, norepinephrine and glutamate, and inhibits the activation of soluble guanylate cyclase, which in turn reduces the production of cyclic guanosine monophosphate (cGMP), thereby reducing anxiety (75).