85. Environmental mold, brain inflammation, cognitive deficits, and increased anxiety and fear

Abstract

Exposure to mold in water-damaged buildings can have severe adverse effects on human health. Despite evidence that mold exposure causes increased anxiety, depression, chronic fatigue, pain, and cognitive problems, no animal research has been published examining how mold exposure causes these problems. We examined the effects of exposing mice to spores of Stachybotrys chartarum, probably the most studied of the damp-building molds. Mice were exposed to either intact Stachybotrys spores, containing a variety of potent toxins and proteinases (IN), to spores extracted twice with alcohol to remove spore contents (EX), or to saline vehicle (VEH). Both types of spores cause significant memory deficits on a contextual memory task. Mice treated with extracted spores show significantly higher levels of anxiety, while mice treated with intact spores are more fearful of an auditory tone previously paired with a mild footshock. Spore inhalation significantly increased numbers of interleukin-1β-immunoreactive cells in the dorsomedial hippocampus In IN males, with EX males being intermediate between IN and VEH males. EX treatment significantly decreased numbers of immature new neurons as quantified by doublecortin, while IN treatment significantly reduced numbers of mature new neurons as quantified by double labeling with BrdU and NeuN. Our data suggest that respiratory exposure to any mold, not just the particularly toxic ones like Stachybotrys, may be capable of causing brain inflammation, cognitive deficits, and emotional problems.