Heme induces intestinal epithelial cell ferroptosis via mitochondrial dysfunction in transfusion‐associated necrotizing enterocolitis

Abstract

Transfusion-associated necrotising enterocolitis (TANEC) is a life-threatening disease with a poor prognosis in preterm infants. This study explored whether and how heme induces ferroptosis in TANEC gut injury. A TANEC mouse model and a cell culture system for heme and Caco-2 cells were established. Ferroptosis was assessed by measuring iron and malondialdehyde (MDA) levels and mitochondrial morphology in intestinal tissues and Caco-2 cells. Mitochondrial dysfunction was evaluated by measuring mitochondrial reactive oxygen species (ROS) production and membrane potential using JC-1. The intestinal injury grade was higher in the anemia-transfusion group than in the control group (p < .0001). Higher intestinal iron concentration (p < .0001), elevated levels of lipid peroxidation MDA (p = .0021), and ferroptotic mitochondrial morphological changes were found in mice of the anemia-transfusion group; specific ferroptosis inhibitor could alleviate anemia-transfusion gut injury, suggesting that ferroptosis play a role in the TANEC gut injury. Next, we explored whether heme released by hemolysis of erythrocytes induces ferroptosis in intestinal epithelial cells in vitro. The viability of Caco-2 cells significantly decreased after heme treatment (p < .0001). Iron accumulation, MDA elevated levels, and mitochondrial dysfunction also existed in the co-culture system, which ferroptosis inhibitors could reduce. In summary, ferroptosis was discovered in TANEC, and heme could induce ferroptosis in intestinal epithelial cells via mitochondrial dysfunction. Heme-inducing ferroptosis may be a possible mechanism and therapeutic target for TANEC.

Alpha1-antitrypsin improves survival in murine abdominal sepsis model by decreasing inflammation and sequestration of free heme

“…This is in line with our previous observation that incubation of human neutrophils for 5 h with 4 mM hemin only slightly and not significantly increased the number of apoptotic cells but strongly increased the number of non-viable neutrophils ( 56 ). Some researchers suspect that heme induces cell ferroptosis via mitochondrial dysfunction ( 67 ). In addition, free heme is a well-known inducer of heme oxygenase-1 (HO-1), particularly in monocyte/macrophage cells ( 53 ), which has been implicated as a key mediator of inflammatory cell and tissue injury, as validated in preclinical models of acute lung injury and sepsis ( 68 ).…”

BACH1 promotes tissue necrosis and Mycobacterium tuberculosis susceptibility

“…Interestingly, Bach1 activity is known to be repressed by its interaction with haem 24 . However, haem by itself is cytotoxic due to its induction of ferroptosis 48 , 49 , thus ruling out its use as a host-directed therapy for suppressing Bach1 activity. Nevertheless, the discovery and development of other pharmacologically acceptable inhibitors of Bach1 would seem a fruitful strategy, impacting a wide variety of diseases in which lipid peroxidation-mediated cellular necrosis is known as an important mechanism underlying pathogenesis.…”

Heme Oxygenase-1 and Its Role in Colorectal Cancer

“…Nevertheless, free ferrous iron (Fe 2+ ) is oxidized to ferric iron (Fe 3+ ) and stored by ferritin or directly exported out of the cell by FPN-1, which was shown to be an effective protection mechanism against ferroptosis [115,116]. HO-1 knockdown in non-malignant human colonocytes did not affect the expression of ferritin, but heme as the HO-1 substrate induces the expression of ferritin, which was shown in normal human colonocytes and human CRC cells [21,203]. Heme-treated Caco-2 CRC cells showed higher ferrous iron levels, followed by an increase in lipid peroxidation and signs of ferroptotic cell death [203].…”