Expanded polyglutamine ( polyQ) proteins causing spinocerebellar ataxia commonly induce abnormal protein aggregation and apoptosis.PolyQ aggregation has been linked to the activation of endoplasmic reticulum (ER) stress and excitotoxicity.Thus,we aimed to identify effective Chinese herbal medicine (CHM) against ER stress and excitotoxicity induced by mutant polyQ proteins.We identified NH018 as an effective CHM against thapsigargain- or tunicamycin-triggered ER stress-mediated cell death.