D-Ribose Attenuates Ischemia/Reperfusion-Induced Renal Injury by Reducing Neutrophil Activation in Rats

The ischemia/reperfusion (I/R) represents a common pathological mechanism that causes renal injuries. A monosaccharide D-allose has been shown to inhibit neutrophil activation, which is involved in the I/R-induced organ injuries. We therefore examined the role of D-ribose in the I/R-induced renal injury using a rat model. D-ribose, a monosaccharide found in all living cells, serves as a key component of adenosine-5'-triphosphate and nicotinamide adenine dinucleotide. Male Wistar rats were divided into the sham, control and D-ribose groups. In the control and D-ribose groups, rats were subjected to 45 min of left renal ischemia, followed by 24 h of reperfusion, while the I/R procedure was not performed in the sham group. Rats were intravenously administered D-ribose (sham group and D-ribose group, 400 mg/kg) or saline (control group) 30 min before ischemia. Blood urea nitrogen (BUN), serum creatinine and urinary N-acetyl β-D-glucosaminidase (NAG) were measured as indicators of glomerular function and proximal tubular function. We also measured cytokine-induced neutrophil chemoattractant-1 (CINC-1) and myeloperoxidase concentrations to assess neutrophil activation and infiltration, respectively. The tissue sections were scored to evaluate the tubular injury. In the control group, BUN, creatinine, NAG, CINC-1, myeloperoxidase, histological severity score, and number of infiltrating neutrophils were increased following I/R insult, as compared with the sham group. Such increases in biochemical markers, severity score, and infiltrating neutrophils were significantly inhibited in the D-ribose group. Thus, D-ribose ameliorates the I/R-induced renal injury probably by inhibiting neutrophil activation, and may be useful in attenuating the renal injury associated with renal ischemia.