Changes of CCAAT enhancer-binding proteins (CEBPs) in the lung of streptozotocin-induced diabetic rats.
CCAAT enhancer-binding proteins (CEBPs) play key roles in the metabolic regulation, cell transformation, and inflammation. However, the expression and/or functions of CEBPs in rats with hyperglycemia are still unclear. In the present study, we investigated the changes of CEBPs protein in lung of the diabetic rats. The levels of C/EBPβ and C/EBPδ protein were decreased in the lung isolated from streptozotocin-induced diabetic rats (STZ-diabetic rats) as compared with that of normal rats. Exogenous insulin at the dose sufficient to normalize the plasma glucose of STZ-diabetic rats reversed the protein levels of C/EBPβ and C/EBPδ in lung after a 4-day treatment. Similar results were also observed in STZ-diabetic rats that received the treatment of phlorizin to reverse the plasma glucose level for 4 days. Otherwise, the protein level of C/EBPα in lung of the STZ-diabetic rats was similar as the normal rats. Also, the level of C/EBPα protein in lung of the STZ-diabetic rat was not significantly changed by correction of plasma glucose by exogenous insulin or phlorizin. In addition, we also cultured human lung cells (A-549) and rat lung cells (L2) in varies concentration of D-glucose and L-glucose to identify the effect of glucose in expression of C/EBPs. The obtained results suggest that increase of plasma glucose is related to the lower expression of C/EBPβ and C/EBPδ proteins in the lung of STZ-diabetic rats. The changes of expression of C/EBPβ and C/EBPδ are not caused by changes of osmolarity but by D-glucose itself.
Department of Surgery, Chi-Mei Medical Center, Yong Kang City, Tainan County, Taiwan, ROC.
Y
Y
Fong
K-H
KH
Shen
L-J
LJ
Chen
J-T
JT
Cheng
D000818:Animals; D022763:CCAAT-Enhancer-Binding Protein-alpha / Q000235:genetics / Q000378:metabolism*; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000235:genetics / Q000378:metabolism*; D051743:CCAAT-Enhancer-Binding Protein-delta / Q000235:genetics / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008168:Lung / Q000378:metabolism*; D008297:Male; D010695:Phlorhizin / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin
D022763:CCAAT-Enhancer-Binding Protein-alpha; D022782:CCAAT-Enhancer-Binding Protein-beta; D051743:CCAAT-Enhancer-Binding Protein-delta; D013311:Streptozocin; D010695:Phlorhizin; D005947:Glucose