A betaine-contained solution ameliorates cold ischemia reperfusion injury by suppressing ferroptosis in porcine kidney

Background: Intracellular iron-mediated lipid oxidative damage, referred to as ferroptosis, plays a crucial role in renal ischemia-reperfusion (I/R) injury. This study aims to investigate the effects of a betaine-contained organ preservation solution on renal ferroptosis using the normothermic machine perfusion (NMP) system. Methods: Healthy adult Bama miniature pigs were utilized in this study. Both kidneys were harvested and stored at 4 degrees C using three organ preservation solutions: Hypertonic Citrate Adenine (HCA) solution, University of Wisconsin (UW) solution, and modified multiple-saccharide (MS2) solution, for a duration of 24 h. The kidneys were subsequently divided into HCA, UW, and MS groups. The kidneys stored in cold for 2 h were used as a control. All kidneys were reperfused using the NMP system for 2 h. Biochemical indicators and ferroptosis-related markers, including iron levels, oxidative stress, and Acyl-CoA synthetase long-chain family member 4 (ACSL4), were measured. Results: During the 2-hour NMP, prolonged cold storage and reperfusion significantly induced ferroptosismediated renal I/R injury, resulting in severe renal tubular damage. Notably, levels of lactate dehydrogenase (LDH), malondialdehyde (MDA), ACSL4, and iron were significantly elevated in the HCA group compared to the control group (P < 0.05), while these levels were significantly reduced in the UW and MS groups. Additionally, the MS group exhibited results similar to those of the UW group in preventing renal I/R injury. Conclusion: This study indicates that the betaine-containing MS solution attenuates ferroptosis-mediated renal cold I/R injury by inhibiting oxidative stress.