Postconditioning is protective in renal reperfusion injury only in male rats. A gender difference study

Abstract

Purpose:We investigated the impact of sex on the protective effect of postconditioning (POC), a series of brief ischemia-reperfusion (IR) cycles at the reperfusion onset, as a recently described novel approach to attenuate renal IR injury. In this study, the left renal pedicles of uni-nephrectomized male and female rats were clamped for 45 minutes followed by 24 hours of reperfusion as IR groups. Uni-nephrectomized, sham-operated male and female rats served as control groups. Ischemic postconditioning was performed using 4 cycles of 10 seconds IR of renal pedicle at the end of the ischemia. Twenty-four hours later, BUN (blood urea nitrogen), plasma creatinine (Cr), and renal histological changes, as well as kidney levels of MDA (malondialdehyde) and SOD (superoxide dismutase) as oxidative stress markers were evaluated to detect the protective effect of POC against IR injury in rats. Results: Induction of IR resulted in significant reduction in renal function, demonstrated by increase in plasma Cr and BUN, histological changes and oxidative stress in both genders. Application of POC afforded significant protection against these injuries in male rats, namely decreased levels of BUN and Cr, histological improvements and less oxidative damages. However, there were no significant differences in the above-mentioned parameters in female rats. Conclusion: While POC is shown to be beneficial against renal IR injury in male rats, it did not show any protective effect in female rats.

Scintigraphic evaluation of remote pre-conditioning protection against unilateral renal ischemia/reperfusion injury in rats: a longitudinal study

“…Consistent with 99mTc-DMSA uptake data, most severe histopathological alterations were observed in the ischemic kidneys specimens of IR group which is in line with the results of previous works [23,24]. However, the histopathological results of RPeC-treated animal showed no significant difference compared with the IR group.…”

Preclinical Evidence for the Efficacy of Ischemic Postconditioning against Renal Ischemia-Reperfusion Injury, a Systematic Review and Meta-Analysis

“…Concerning the population under investigation, nearly all preclinical studies used male animals, whereas the clinical trials included both men and women. This sex bias (which is widespread in preclinical studies) is reason for concern, considering the evidence that females react differently to both IRI[ 34 ] and IPoC[ 35 ]. Secondly, we found no studies using animals with relevant comorbidities such as hypertension or diabetes mellitus, which are often present in patients undergoing renal surgery or transplantation.…”