Dietary DHA is incorporated into neural and plasma cell membranes. In the brain, incorporation of DHA into cell membranes results in increased fluidity and permeability.] These alterations in membrane properties determine the binding or release of neurotransmitters, thus affecting cellular signaling.
DHA may also quicken neurotransmission by enhancing glutamatergic synaptic activity Hippocampal neurons with DHA significantly increased spontaneous synaptic activity compared with neurons treated with arachidonic acid or controls
In human retinal pigment epithelial cells, neuroprotectins D1, a metabolite of DHA, exerts prominent antiapoptotic properties by upregulating the antiapoptotic proteins Bcl-2 and Bcl-xL and decreasing proapoptotic Bax and Bad expression.
Neuroprotectin D1 also counteracts leukocyte infiltration, NF-κB activation and proinflammatory gene expression in brain ischemia–reperfusion.[20]By contrast, in several neoplastic disorders, including acute myeloid leukemia, as well as breast, ovarian, pancreatic, prostate, renal and colorectal cancer, DHA may exert antineoplastic properties by promoting tumor cell apoptosis.
DHA has been shown to support neuronal proliferation and decrease neuron apoptosis.[77]Brains of infants born before 33 weeks’ gestation are relatively deficient in DHA compared with brains of infants born at term, and survivors of prematurity exhibit permanently reduced gray and white matter volumes.
School-age children with attention-deficit hyperactivity disorder (ADHD) have been demonstrated to have significantly lower plasma levels of DHA and arachidonic acid than normal control.