Gene expression of glucose transporters and its regulation by glucose in mesothelial cells.

OBJECTIVE: To observe the influence of glucose on the expression of glucose transporters (GluTs) in peritoneal tissues. METHODS: Mesothelial cells (MsCs) from Sprague-Dawley (SD) rats were cultured in medium with glucose 214.4 mmol/L or 75.5 mmol/L. The normal medium with glucose 17.5 mmol/L was used as control. Total RNA was extracted from each sample after 24 hours incubation. Reverse transcript polymerase chain reaction (RT-PCR) was performed with primers corresponding to sodium-glucose transporter (SGIT1) and GluT1-GluT4. mRNA expression of the above GluTs from each sample was measured with quantitative PCR. RESULTS: GluT1 and GluT2 mRNA can be detected in MsCs from SD rats, while no positive bands can be found specifically for GluT3, GluT4 and SGiT1. Quantitating the amount of PCR products indicated that the levels of GluT1 mRNA in MsCs cultured 24 h in both 214.4 mmol/L glucose and 75.5 mmol/L glucose medium decreased dramatically compared with that in normal medium (P < or = 0.01). While under the same conditions, the levels of GluT2 mRNA in MsCs cultured 24 h in 214.4 mmol/L and 75.5 mmol/L glucose medium both increased significantly (P < 0.01). CONCLUSIONS: GluT1 is strongly expressed in MsCs under normal glucose levels and decreased dramatically under high glucose conditions, while GluT2 expressed at a low level in normal medium and increased greatly after incubation in high glucose conditions. This may play a great role in glucose absorption during peritoneal dialysis and have some connection with ultrafiltration failure due to the alteration of glucose absorption after long-term dialysis.