Carbonyl reductase 1 protects pancreatic β-cells against oxidative stress-induced apoptosis in glucotoxicity and glucolipotoxicity.
Carbonyl reductase 1 (CBR1) plays an important role in the detoxification of reactive lipid aldehydes. Oxidative stress has been implicated in the pathogenesis of pancreatic β-cell failure. However, the functional role of CBR1 in pancreatic β-cell failure has not been studied yet. Therefore, we investigated the role of CBR1 in pancreatic β-cell failure under glucotoxic and glucolipotoxic conditions. Under both conditions, knockdown of CBR1 by specific siRNA increased β-cell apoptosis, expression of lipogenic enzymes (such as ACC, FAS, and ABCA1), intracellular lipid accumulation, oxidative stress, ER stress, and nuclear SREBP1c, but decreased glucose-stimulated insulin secretion. In contrast, overexpression of CBR1 showed the opposite effects. The antioxidants N-acetyl-l-cysteine and Tiron, as well as the FAS inhibitor cerulenin, reversed the effects of CBR1 knockdown. Interestingly, the expression level and enzyme activity of CBR1 were significantly decreased in pancreatic islets of db/db mice, compared with those of wild-type mice. In conclusion, CBR1 protects pancreatic β-cells against oxidative stress and promotes their survival in glucotoxicity and glucolipotoxicity.
Rashid
M A
MA
Medical Science and Engineering Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute (BK-21), Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 130-701, Korea.
Lee
Seonmin
S
Tak
Eunyoung
E
Lee
Jisun
J
Choi
Tae Gyu
TG
Lee
Joo-Won
JW
Kim
Jae Bum
JB
Youn
Jang H
JH
Kang
Insug
I
Ha
Joohun
J
Kim
Sung Soo
SS
D000429:Alcohol Oxidoreductases / Q000096:biosynthesis / Q000502:physiology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002478:Cells, Cultured; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology; D005227:Fatty Acids / Q000633:toxicity; D055785:Gene Knockdown Techniques; D005947:Glucose / Q000633:toxicity; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000187:drug effects*; D051379:Mice; D018384:Oxidative Stress / Q000187:drug effects*; D034622:RNA Interference; D017382:Reactive Oxygen Species / Q000378:metabolism; D051780:Sterol Regulatory Element Binding Protein 1 / Q000378:metabolism
D005227:Fatty Acids; D007328:Insulin; D017382:Reactive Oxygen Species; C497388:Srebf1 protein, mouse; D051780:Sterol Regulatory Element Binding Protein 1; D000429:Alcohol Oxidoreductases; C555915:carbonyl reductase 1, mouse; D005947:Glucose