Dimethyl sulphoxide administration decreases renal ischemic–reperfusion injury

Introduction

Kidney ischemia is one of the mechanisms of acute renal failure and it is known that the free oxygen radicals play an important role in this type of injury. We tested the hypothesis that dimethyl sulphoxide (DMSO), a free radical scavenger, has a protective role in a renal ischemia–reperfusion animal model [1].

Methods

Renal ischemia was induced to 45 male, New Zealand rabbits. The subjects were divided into three groups based on ischemia duration: 30, 60 or 90 minutes. Each group was divided into three subgroups: (a) DMSO previous to ischemia, (b) DMSO after ischemia, (c) control group. All subjects were given 6 hours of reperfusion. Three blood samples were taken at baseline, ischemic and reperfusion phases. Each sample was tested for serum creatinine, blood ureic nitrogen and urea. After reperfusion, bilateral nephrectomy was performed on each subject before euthanasia. A pathological analysis evaluated tubular and basement membrane changes. The level of injury was scaled in three stages: mild, moderate and severe.

Results

The histological analysis showed severe damage in 33% of the control group, compared with 0% in both treatment groups (chi-square P = 0.00) (Table 1). Blood chemistry analysis in the control group at 60 and 90 minutes of ischemia showed higher values than both treatment groups. Creatinine values were analyzed over a proportion estimate, showing that 26% of subjects in the control group had an improvement comparing the ischemic phase versus the reperfusion phase. Treatment groups showed that 46% and 60% of the subjects improved their creatinine values when DMSO was administered pre ischemia and post ischemia, respectively.

Table 1 Proportion estimate of histopathological findings

Conclusion

The animal model showed an increasing trend of all blood chemistry parameters evaluated in the control group. DMSO applied as prophylaxis or treatment post ischemia demonstrates diminished renal function deterioration. Histological analysis revealed the absence of severe lesions when DMSO is administered.