Renoprotective effect of monk fruit (siraitia grosvenori) extract on renal ischemia-reperfusion injury in rat model

Purpose Renal ischemia, induced during various kidney surgeries, is necessary but could also lead to renal inflammation and injuries. We hypothesized that oxidative stress (OXS) is a primary cause of such injuries, particularly renal ischemia-reperfusion injury (RIRI), and that antioxidants could mitigate it. Hence, we investigated if LLE (monk fruit extract) with antioxidant activity might reduce/prevent the incidence of warm ischemia-induced RIRI in rats. Methods Sprague-Dawley rats were randomly assigned to one of three groups: (1) Sham, (2) Ischemia-reperfusion (RIR), and (3) RIR with LLE supplementation (RIR+LLE). Rats were subjected to40-min ischemia byrenal pedicle clamping, followed by 24-h reperfusion. LLE was given to rats 30 min prior toischemia and immediately before the reperfusion interval. Results The RIR group showed palpable kidney injuries with significantly elevated blood urea nitrogen (BUN) and creatinine (Cr) levels, indicating renal dysfunction. However, the kidneys in the RIR+LLE group appeared merely normal with basal BUN/Cr levels, similar to the Sham group, indicating normal renal function. Moreover, OXS was ~2.3-fold severer, two antioxidant enzymes were inactivated, and three kidney injury markers (NGL, Kim-1, and CLU) were up-regulated in the RIR group. In contrast, a few changes in OXS, enzymatic activities, and marker expression were observed in the RIR+LLE group. Conclusion This study demonstrates that OXS plays a key role in RIRI, while LLE with antioxidant activity effectively protects the kidneys from it. Thus, LLE warrants consideration as a potential perioperative renoprotective agent for clinical use.