3,4-dideoxyglucosone-3-ene induces apoptosis in human peritoneal mesothelial cells.
OBJECTIVE
Glucose degradation products (GDPs) are formed during heat sterilization and storage of peritoneal dialysis (PD) fluids. 3,4-dideoxyglucosone-3-ene (3,4-DGE) has been identified as the most bioreactive GDP. 3,4-DGE induces apoptosis in leukocytes and renal tubular epithelial cells. Our aim was to evaluate the apoptotic effects of 3,4-DGE on human peritoneal mesothelial cells (HPMCs).


METHODS
Primary cultured HPMCs were treated with 25 or 50 micromol/L 3,4-DGE. MTT assay was used to determine cell viability. Apoptosis was measured using TUNEL assay and flow cytometry. Expressions of procaspase-3, Bax, and Bcl-2 were estimated by Western blot. Activity of caspase-3 was measured and the effect of the caspase inhibitor zVAD-fmk (Z-Val-Ala-DL-Asp-fluoromethylketone) was evaluated by TUNEL assay.


RESULTS
3,4-DGE treatment accelerated cell death in HPMCs in a dose- and time-dependent manner. Treatment with 3,4-DGE (25 and 50 micromol/L) significantly increased apoptosis compared to control (p<0.05 and p<0.01 respectively) by TUNEL assay. Flow cytometry showed treatment with 50 micromol/L 3,4-DGE significantly increased apoptosis compared to control (p<0.05). Decreased expression of procaspase-3 and increased activity of caspase-3 were observed in the presence of 50 micromol/L 3,4-DGE compared to control and 25 micromol/L 3,4-DGE (p<0.05). 3,4-DGE-induced HPMC apoptosis was decreased after pretreatment with the pan-caspase inhibitor zVAD-fmk in the 50 micromol/L 3,4-DGE-treated group (p<0.001). The ratio of Bcl-2 to Bax expression was decreased in the 25 micromol/L and the 50 micromol/L 3,4-DGE-treated groups compared to control (p<0.05).


CONCLUSIONS
3,4-DGE promotes apoptosis in HPMCs by a caspase-related mechanism.
Lee
Duk-Hyun
DH
Department of Internal Medicine, Daegu Fatima Hospital, and Kyungpook National University School of Medicine, Daegu, Korea.
Choi
Soon-Youn
SY
Ryu
Hye-Myung
HM
Kim
Chan-Duck
CD
Park
Sun-Hee
SH
Chung
Ho-Young
HY
Kim
In-San
IS
Kim
Yong-Lim
YL
D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D053148:Caspase 3 / Q000096:biosynthesis / Q000187:drug effects; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D005434:Flow Cytometry; D024981:Glycogen Phosphorylase / Q000037:antagonists & inhibitors; D006801:Humans; D020287:In Situ Nick-End Labeling; D010537:Peritoneum / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis / Q000187:drug effects; D011753:Pyrones / Q000494:pharmacology*; D051028:bcl-2-Associated X Protein / Q000096:biosynthesis / Q000187:drug effects
C504711:3,4-dideoxyglucosone-3-ene; D019253:Proto-Oncogene Proteins c-bcl-2; D011753:Pyrones; D051028:bcl-2-Associated X Protein; D024981:Glycogen Phosphorylase; D053148:Caspase 3