TY - JOUR
T1 - Tetraspanin-2 promotes glucotoxic apoptosis by regulating the JNK/β-catenin signaling pathway in human pancreatic β cells
AU - Hwang, In Hu
AU - Park, Junsoo
AU - Kim, Jung Min
AU - Il Kim, Seung
AU - Choi, Jong Soon
AU - Lee, Kyung Bok
AU - Yun, Sung Ho
AU - Lee, Min Goo
AU - Park, Soo Jung
AU - Jang, Ik Soon
N1 - Funding Information:
This work was supported by the Basic Science Research Programthrough the National Research Foundation of Korea (NRF), funded by Ministry of Education Grants 2015R1D1A1A01058744 and 2014R1A1A2058114, and supported by Korea Basic Science Institute Grant D36403.
Publisher Copyright:
© The Author(s).
PY - 2016/9
Y1 - 2016/9
N2 - Diabetes mellitus is a complex and heterogeneous disease, which has β-cell dysfunction at its core. Glucotoxicity affects pancreatic islets, causing β-cell apoptosis. However, the role of JNK/β-catenin signaling in glucotoxic β-cell apoptosis is not well understood. Recently, we identified tetraspanin-2 (TSPAN2) protein as a proapoptotic β-cell factor induced by glucose, suggesting that TSPAN2 might contribute to pancreatic β-cell glucotoxicity. To investigate the effects of glucose concentration on TSPAN2 expression and apoptosis, we used reverted immortalizedRNAKT-15 human pancreatic β cells.High TSPAN2 levels up-regulated phosphorylated (p) JNK and induced apoptosis. p-JNK enhanced the phosphorylation of b-catenin and Dickkopf-1 (Dkk1). Dkk1 knockdownbysmall interfering (si)RNAup-regulated nuclearb-catenin, suggestingthat it isaJNK/β-catenin-dependent pathway. siRNA-mediatedTSPAN2depletion inRNAKT-15 cells increased nuclearb-catenin.ThisdecreasedBCL2- associated X protein (Bax) activation, leading to marked protection against high glucose-induced apoptosis. Bax subfamily proteins induced apoptosis through caspase-3. Thus, TSPAN2might have induced Bax translocation and caspase-3 activation in pancreatic β cells, thereby promoting the apoptosis ofRNAKT-15 cells by regulating the JNK/ b-catenin pathway in response to high glucose concentrations. Targeting TSPAN2 could be a potential therapeutic strategy to treat glucose toxicity-inducedβ-cell failure.-Hwang, I.-H., Park, J., Kim,J.M., Kim,S. I.,Choi, J.-S.,Lee, K.-B., Yun, S. H., Lee, M.-G., Park, S. J., Jang, I.-S. Tetraspanin-2 promotes glucotoxic apoptosis by regulating the JNK/β-catenin signaling pathway in human pancreatic β cells.
AB - Diabetes mellitus is a complex and heterogeneous disease, which has β-cell dysfunction at its core. Glucotoxicity affects pancreatic islets, causing β-cell apoptosis. However, the role of JNK/β-catenin signaling in glucotoxic β-cell apoptosis is not well understood. Recently, we identified tetraspanin-2 (TSPAN2) protein as a proapoptotic β-cell factor induced by glucose, suggesting that TSPAN2 might contribute to pancreatic β-cell glucotoxicity. To investigate the effects of glucose concentration on TSPAN2 expression and apoptosis, we used reverted immortalizedRNAKT-15 human pancreatic β cells.High TSPAN2 levels up-regulated phosphorylated (p) JNK and induced apoptosis. p-JNK enhanced the phosphorylation of b-catenin and Dickkopf-1 (Dkk1). Dkk1 knockdownbysmall interfering (si)RNAup-regulated nuclearb-catenin, suggestingthat it isaJNK/β-catenin-dependent pathway. siRNA-mediatedTSPAN2depletion inRNAKT-15 cells increased nuclearb-catenin.ThisdecreasedBCL2- associated X protein (Bax) activation, leading to marked protection against high glucose-induced apoptosis. Bax subfamily proteins induced apoptosis through caspase-3. Thus, TSPAN2might have induced Bax translocation and caspase-3 activation in pancreatic β cells, thereby promoting the apoptosis ofRNAKT-15 cells by regulating the JNK/ b-catenin pathway in response to high glucose concentrations. Targeting TSPAN2 could be a potential therapeutic strategy to treat glucose toxicity-inducedβ-cell failure.-Hwang, I.-H., Park, J., Kim,J.M., Kim,S. I.,Choi, J.-S.,Lee, K.-B., Yun, S. H., Lee, M.-G., Park, S. J., Jang, I.-S. Tetraspanin-2 promotes glucotoxic apoptosis by regulating the JNK/β-catenin signaling pathway in human pancreatic β cells.
KW - Bax
KW - Glucose toxicity
KW - TSPAN2
UR - http://www.scopus.com/inward/record.url?scp=84990852792&partnerID=8YFLogxK
U2 - 10.1096/fj.201600240RR
DO - 10.1096/fj.201600240RR
M3 - Article
C2 - 27247127
AN - SCOPUS:84990852792
VL - 30
SP - 3107
EP - 3116
JO - The FASEB journal : official publication of the Federation of American Societies for Experimental Biology
JF - The FASEB journal : official publication of the Federation of American Societies for Experimental Biology
SN - 1530-6860
IS - 9
ER -