Ketamine induces endoplasmic reticulum stress in rats and SV-HUC-1 human uroepithelial cells by activating NLRP3/TXNIP aix

Many clinical studies have been conducted on ketamine-associated cystitis. However, the underlying mechanisms of ketamine-associated cystitis still remain unclear. Bladder tissues of rats were stained by Hematoxylin and Eosin (HE). The viability of human uroepithelial cells (SV-HUC-1 cells) was determined by cell counting kit-8 (CCK-8). Apoptosis and reactive oxygen species (ROS) were examined by flow cytometry. Additionally, the expressions of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1β and IL-18 were respectively determined by reverse transcription quantitative (RTq)-PCR and enzyme-linked immunosorbent assay (ELISA). The mRNA and protein levels of B-cell lymphoma/leukemia-2 (Bcl2), Bcl-2-associated X protein (Bax), cleaved caspase 3, glucose-regulated protein 78 (GRP78), CCAAT/enhancer binding protein homologous protein (CHOP), NOD-like receptor 3 (NLRP3), thioredoxin-interacting protein (TXNIP), Catalase and MnSOD were examined by RT-qPCR and Western blot. Small interfering RNA target TXNIP transfection was performed using Lipofectamine™ 2000. We found that ketamine effectively damaged bladder tissues of rats and promoted apoptosis through regulating the expression levels of GRP78, CHOP, Bcl-2, Bax and cleaved Caspase-3 proteins in vivo and in vitro. NLRP3 inflammatory body and TXNIP were activated by ketamine, which was supported by the changes in TNF-α, IL-6, IL-1 and IL-18 in vivo and in vitro. Furthermore, knocking down TXNIP reversed the effects of ketamine on apoptosis and NLRP3 inflammatory body in SV-HUC-1 cells. Meanwhile, the changes of Catalase and MnSOD showed that ROS was enhanced by ketamine, however, such an effect was ameliorated by down-regulation of TXNIP in SV-HUC-1 cells. Ketamine promoted cell apoptosis and induced inflammation in vivo and in vitro by regulating NLRP3/TXNIP aix.