HD Glossary

Note: Some words can have differing definitions depending on the context in which they are used. The definitions presented here are the ones that best apply to the words as they are used. HDSA is grateful to the Stanford Hopes website for their contribution and maintenance of this glossary.



  • 2-DG 2-deoxy-D-glucose. - A substance that helps induce autophagy and thus decrease huntingtin protein aggregation. Also has been shown to increase levels of HSP-70 and GRP-78.
  • 3-hydroxykynurenin (3HK) - A free radical generator that is present in increased amounts in humans with HD and HD mice.
  • 3-NP - Abbreviation for 3-nitroproprionic acid.
  • 3-nitroproprionic acid (3-NP) - An inhibitor of complex II of the mitochondrial electron transport chain. It binds to a site in the complex II protein, preventing it from performing its usual function.
  • 5-lipoxygenase - An enzyme that leads to the production of leukotrienes, which are chemicals that contribute significantly to inflammation.
  • 5-hydroxyindoleacetic acid (5-HIAA) - A molecule that is made from serotonin. It is present in decreased levels in the brains of HD mice.