KHG21834 attenuates glutamate-induced mitochondrial damage, apoptosis, and NLRP3 inflammasome activation in SH-SY5Y human neuroblastoma cells

New compounds were screened to develop effective drugs against glutamate-induced toxicity. The present study assessed the effects of the novel thiazole derivative KHG21834 against glutamate-induced toxicity in human neuroblastoma SH-SY5Y cell cultures. Treatment of SH-SY5Y cells with KHG21834 significantly protected cells against glutamate-induced toxicity in a dose-dependent manner, with an optimum concentration of 50 μM. KHG21834 protected SH-SY5Y cells against glutamate toxicity by suppressing glutamate-induced oxidative stress by 50%. KHG21834 also attenuated glutamate-induced mitochondrial membrane potential, ATP level reductions, and intracellular Ca²⁺ influx. Furthermore, KHG21834 efficiently reduced glutamate-induced ER stress and NLRP3 inflammasome activation (59% and 65% of glutamate group, respectively). In addition, KHG21834 effectively attenuated glutamate-induced levels of Bax, Bcl-2, cleaved caspase-3, p-p38, p-JNK proteins, and TUNEL positive cells. To our knowledge, this is the first study showing that KHG21834 can effectively protect SH-SY5Y cells against glutamate toxicity, suggesting that this compound may be a valuable therapeutic agent for the treatment of glutamate toxicity.

Antioxidative effects of ethyl 2-(3-(benzo[d]thiazol-2-yl)ureido)acetate against amyloid β-induced oxidative cell death via NF-κB, GSK-3β and β-catenin signaling pathways in cultured cortical neurons

We have previously shown that 2-(3-(benzo[d]thiazol-2-yl)ureido)acetate (KHG21834) attenuates amyloid beta(Aβ)25-35-induced apoptotic death and shows anti-inflammatory activity against Aβ25-35-induced microglial activation. However, antioxidative effects of KHG21834 against Aβ-induced oxidative stress have not yet been reported. In the present study, we investigated the antioxidative function of KHG21834 in primary cultured cortical neurons, to expand the potential therapeutic efficacy of KHG21834. Pretreatment with KHG21834 protected against Aβ-induced neuronal cell death and mitochondrial damage, and significantly restored GSH levels and the activities of catalase, superoxide dismutase, and glutathione peroxidase, and also suppressed the production of reactive oxygen species and protein oxidation. These results imply that KHG21834 may play a role in cellular defense mechanisms against Aβ-induced oxidative stress in cultured cortical neurons. Furthermore, KHG21834 significantly attenuated the effects of Aβ treatment on levels of NF-κB, β-catenin, and GSK-3β proteins in cortical neurons. Taken together, our results suggest that the antioxidant effects of KHG21834 may result at least in part from its ability to regulate the NF-κB, β-catenin, and GSK-3β signaling pathways. To our knowledge, this is the first report showing that KHG21834 significantly attenuates Aβ25-35-induced oxidative stress in primary cortical neurons, and provides novel insights into KHG21834 as a possible therapeutic agent for the treatment of Aβ-mediated neurotoxicity involving oxidative stress.