Beta-hexosaminidase (HEX)

Beta-hexosaminidase is a critical lysosomal hydrolase responsible for the degradation of GM2 gangliosides and other terminal N-acetylhexosamine-containing oligosaccharides. The enzyme exists as two major isoforms: Hexosaminidase A (alpha-beta heterodimer) and Hexosaminidase B (beta-beta homodimer), with mutations in the respective subunits leading to severe neurodegenerative lysosomal storage disorders such as Tay-Sachs and Sandhoff disease (UniProt P06865, P07686). Beyond its metabolic role, beta-hexosaminidase is stored in the secretory granules of mast cells and basophils; its release is a hallmark of degranulation following IgE-mediated activation of the FcεRI receptor (PubMed: 11563483). Consequently, the beta-hexosaminidase release pathway is widely employed in pharmacological research as a surrogate biomarker for mast cell activation and to evaluate the efficacy of anti-allergic and anti-inflammatory candidates. Therapeutic strategies targeting the enzyme itself include the use of pharmacological chaperones like pyrimethamine to stabilize misfolded proteins and restore lysosomal function, as well as substrate reduction therapies to mitigate toxic metabolite accumulation (PubMed: 19116317). While drugs like pyrimethamine act as chaperones for the enzyme, other compounds may target the signaling proteins upstream in the release pathway to prevent degranulation in allergic contexts.

Other names

N-acetyl-beta-glucosaminidaseHexosaminidase AHexosaminidase BHEXAHEXB

Pharmacological chaperoning to stabilize misfolded enzyme variants and restore lysosomal trafficking.