NLRX1 accelerates cisplatin-induced ototoxity in HEI-OC1 cells via promoting generation of ROS and activation of JNK signaling pathway.

Abstract

Nucleotide-binding domain and leucine-rich-repeat-containing family member X1 (NLRX1), located in mitochondria, can recognize cytoplasmic pattern recognition receptors and is tightly related to reactive oxygen species (ROS) production, mitochondrial function, apoptosis and inflammation. The present study was designed to explore whether NLRX1 expresses in HEI-OC1 cells and, if so, to investigate the possible correlations between NLRX1 and cisplatin-induced ototoxity in vitro. Here, we report that NLRX1 was specifically localized to mitochondria in the cytoplasm of HEI-OC1 cells and its expression was increased concurrent with the increase of ROS production and occurrence of apoptosis in HEI-OC1 cells in response to cisplatin stimulus. NLRX1 overexpression led to a higher apoptosis in HEI-OC1 cells treated with cisplatin, whereas, NLRX silencing decreased cisplatin induced apoptosis. Mechanistic studies showed that NLRX1 activated mitochondrial apoptosis pathway as well as promoted ROS generation and JNK activation. Either inhibition of ROS generation or JNK signaling significantly prevented NLRX1-mediated mitochondrial apoptosis in HEI-OC1cells. In addition, NLRX1 expression was confirmed in cochlear explants. The findings from this work reveal that NLRX1 sensitizes HEI-OC1 cells to cisplatin-induced apoptosis via activation of ROS/JNK signaling pathway, suggesting that NLRX1 acts as an important regulator of the cisplatin-elicited ototoxity.

• Authors: Haiyan Yin, Gaoying Sun, Qianqian Yang, Chen Chen, Qi Qi, Haibo Wang, Jianfeng Li
• Journal: Scientific reports (Sci Rep) Vol. 7 Pg. 44311 (03 13 2017) ISSN: 2045-2322 [Electronic] England
• PMID: 28287190 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antineoplastic Agents
• Mitochondrial Proteins
• NLRX1 protein, mouse
• Reactive Oxygen Species
• Cisplatin

Topics

• Animals
• Antineoplastic Agents (pharmacology)
• Apoptosis (drug effects)
• Cell Line
• Cell Survival (drug effects)
• Cisplatin (pharmacology)
• Cochlea (cytology, drug effects, metabolism)
• Gene Expression
• Hair Cells, Auditory (cytology, drug effects, metabolism)
• MAP Kinase Signaling System (drug effects)
• Mice
• Mitochondria (drug effects, genetics, metabolism)
• Mitochondrial Proteins (genetics, metabolism)
• RNA Interference
• Reactive Oxygen Species (metabolism)