That Gut Feeling May Damage Your Brain

Some people have been accused of thinking with their stomachs (and, for many men, perhaps something a bit lower), but a new study has discovered that there is indeed a distinct -- and dangerous -- link between the gastrointestinal tracts and the brains of HIVers. Scientists at Yeshiva University in New York City report in the Journal of Virology that the condition called 'leaky gut,' in which an intestinal bacterial component called lipopolysaccharide seeps into the bloodstream, helps HIV-infected cells break through the body's blood-brain barrier. Once inside the brain, the virus in the cells begins to replicate, potentially causing dementia and other cognitive disorders. About 20% of HIVers have viral infections that have spread to their brains. 'Clearly, HIV-infected monocytes uniquely benefit from lipopolysaccharide,' concludes lead researcher Harris Goldstein. 'So when HIV-infected monocytes are 'knocking on the door' of the blood-brain barrier and starting to crack it open, the lipopolysaccharide facilitates their entry by making the barrier more permeable, apparently by weakening blood vessel structure.' The researchers hope their findings will lead to preventive or therapeutic strategies to kill intestinal bacteria that make lipopolysaccharide or to clear the compound from the bloodstream.