ChREBP mediates glucose-stimulated pancreatic β-cell proliferation

MR Metukuri, P Zhang, MK Basantani, C Chin… - Diabetes, 2012 - Am Diabetes Assoc
MR Metukuri, P Zhang, MK Basantani, C Chin, RE Stamateris, LC Alonso, KK Takane…
Diabetes, 2012Am Diabetes Assoc
Glucose stimulates rodent and human β-cell replication, but the intracellular signaling
mechanisms are poorly understood. Carbohydrate response element-binding protein
(ChREBP) is a lipogenic glucose-sensing transcription factor with unknown functions in
pancreatic β-cells. We tested the hypothesis that ChREBP is required for glucose-stimulated
β-cell proliferation. The relative expression of ChREBP was determined in liver and β-cells
using quantitative RT-PCR (qRT-PCR), immunoblotting, and immunohistochemistry. Loss …
Glucose stimulates rodent and human β-cell replication, but the intracellular signaling mechanisms are poorly understood. Carbohydrate response element-binding protein (ChREBP) is a lipogenic glucose-sensing transcription factor with unknown functions in pancreatic β-cells. We tested the hypothesis that ChREBP is required for glucose-stimulated β-cell proliferation. The relative expression of ChREBP was determined in liver and β-cells using quantitative RT-PCR (qRT-PCR), immunoblotting, and immunohistochemistry. Loss- and gain-of-function studies were performed using small interfering RNA and genetic deletion of ChREBP and adenoviral overexpression of ChREBP in rodent and human β-cells. Proliferation was measured by 5-bromo-2′-deoxyuridine incorporation, [3H]thymidine incorporation, and fluorescence-activated cell sorter analysis. In addition, the expression of cell cycle regulatory genes was measured by qRT-PCR and immunoblotting. ChREBP expression was comparable with liver in mouse pancreata and in rat and human islets. Depletion of ChREBP decreased glucose-stimulated proliferation in β-cells isolated from ChREBP−/− mice, in INS-1–derived 832/13 cells, and in primary rat and human β-cells. Furthermore, depletion of ChREBP decreased the glucose-stimulated expression of cell cycle accelerators. Overexpression of ChREBP amplified glucose-stimulated proliferation in rat and human β-cells, with concomitant increases in cyclin gene expression. In conclusion, ChREBP mediates glucose-stimulated proliferation in pancreatic β-cells.
Am Diabetes Assoc