To study of using E.coli Nissle1917 which can express FCoAT (EcN-Frc) as probiotic treatment to reduce urine oxalate in a rat model.

Thirty male SD rats were randomly divided into 6 groups (A to F). 1% oxalate was added to the diet for rats in group B, C, D, E, F; while rats in group A received regular diet. Furthermore, 30 minutes before each feeding, each rats in group B received 1 ml suspension, while those in group C, D, E, F was given 1 ml EcN-Frc suspension (10³ viable bacteria). Rats in group C, D, E, F were feeding bacteria every day, once every three days, once a week, respectively. 24-hour urine specimens were obtained on days 0, 3, 6, 9, 14 by placing the rats in metabolic cages.

Hyperoxaluria rats due to high dietary oxalate were treated by EcN-Frc. It can effectively reduce the high urinary oxalate level in rat model since day 3 after supplementation. The effect of the decrease proved directly proportional to the dose of EcN-Frc.But, one dose of EcN-Frc (10³ viable bacteria) can still effectively reduce urinary oxalate in a 2 weeks period. It showed that EcN-Frc had the ability to stay stable in rat’s intestine and grew well. In addition, during 2 weeks period, all rats kept health with no signs of toxicity.

Probiotic administration of low dose EcN-Frc can effectively reduce the high urinary oxalate in hyperoxaluria rats. EcN-Frc can stay stable in rat’s intestine and play a role in degrading oxalate. This approach appears to be safe and good tolerance.