TY - JOUR
T1 - Coupling endoplasmic reticulum stress to cell death program in isolated human pancreatic islets
T2 - Effects of gene transfer of Bcl-2
AU - Contreras, Juan L.
AU - Smyth, Cheryl A.
AU - Bilbao, Guadalupe
AU - Eckstein, Christopher
AU - Young, Carlton J.
AU - Thompson, J. Anthony
AU - Curiel, David T.
AU - Eckhoff, Devin E.
N1 - Funding Information:
Acknowledgments We thank Stacie M. Jenkins, BS, and Barry Grace, BS, CPTC, for their technical assistance during the human islet isolations. This paper was supported by research grants from Diabetes Trust Fund and Protective Life Clinical Initiative Award, University of Alabama at Birmingham.
PY - 2003/7/1
Y1 - 2003/7/1
N2 - A variety of toxic insults can result in endoplasmic reticulum (ER)-stress that ultimately leads to apoptosis. β-cells have a highly developed ER due to a great commitment to insulin production. The present study was carried out to determine the role of ER-stress in isolated human pancreatic islet apoptosis, and the potential protective effects of Bcl-2. Isolated human islets were infected with an adenoviral vector encoding Bcl-2 and then exposed to brefeldin-A, tunicamycin, A23187 and pro-inflammatory cytokines. Activation of caspase-12 was analyzed by means of Western blots. Apoptosis was evaluated using a commercial quantitative assay. ER-stress-inducers promoted caspase-12 activation and apoptosis, effect reversed by overexpression of Bcl-2. Co-localization of caspase-12 and Bcl-2 in the microsomal islet fractions were demonstrated by means of Western blots. We can conclude that the current studies highlight the importance of Bcl-2 as an anti-apoptotic protein, and shed new light on the mechanisms underlying its cytoprotective effects on pancreatic islets.
AB - A variety of toxic insults can result in endoplasmic reticulum (ER)-stress that ultimately leads to apoptosis. β-cells have a highly developed ER due to a great commitment to insulin production. The present study was carried out to determine the role of ER-stress in isolated human pancreatic islet apoptosis, and the potential protective effects of Bcl-2. Isolated human islets were infected with an adenoviral vector encoding Bcl-2 and then exposed to brefeldin-A, tunicamycin, A23187 and pro-inflammatory cytokines. Activation of caspase-12 was analyzed by means of Western blots. Apoptosis was evaluated using a commercial quantitative assay. ER-stress-inducers promoted caspase-12 activation and apoptosis, effect reversed by overexpression of Bcl-2. Co-localization of caspase-12 and Bcl-2 in the microsomal islet fractions were demonstrated by means of Western blots. We can conclude that the current studies highlight the importance of Bcl-2 as an anti-apoptotic protein, and shed new light on the mechanisms underlying its cytoprotective effects on pancreatic islets.
KW - Apoptosis
KW - Bcl-2
KW - Endoplasmic reticulum
KW - Islet transplantation
UR - http://www.scopus.com/inward/record.url?scp=0043028611&partnerID=8YFLogxK
U2 - 10.1111/j.1432-2277.2003.tb00344.x
DO - 10.1111/j.1432-2277.2003.tb00344.x
M3 - Article
C2 - 12819863
AN - SCOPUS:0043028611
SN - 0934-0874
VL - 16
SP - 537
EP - 542
JO - Transplant International
JF - Transplant International
IS - 7
ER -