Frontiers Mast Cell Activation in Brain Injury, Stress, and Post traumatic Stress Disorder and Alzheimer's Disease Pathogenesis Mast cells are hypersensitive immune cells that release histamine and other inflammatory mediatorsoften in response to oxidative stress, environmental toxins, and immune imbalance. Many patients with MCAS have low levels of glutathione. Is Mold Triggering Your Mast Cell Activation Syndrome? Recruitment or activation of mast cells in the liver aggravates the accumulation of fibrosis in carbon tetrachloride induced liver injury ScienceDirect