1. Labile Heme Aggravates Renal Inflammation and Complement Activation After Ischemia Reperfusion Injury
- Author
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Ralf Lichtinghagen, Anja Thorenz, Markus Huber-Lang, Song Rong, Cees van Kooten, Mi-Sun Jang, Jan Hinrich Bräsen, Nelli Shushakova, Igor Tudorache, Katja Derlin, Nodir Madrahimov, Rongjun Chen, Stephan Immenschuh, Li Wang, Faikah Gueler, Hermann Haller, Pooja Pradhan, Kukuh Madyaningrana, Robert Greite, and Vijith Vijayan
- Subjects
0301 basic medicine ,Male ,Receptor expression ,urologic and male genital diseases ,Kidney ,Receptors, G-Protein-Coupled ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Immunology and Allergy ,complement ,Heme ,Complement Activation ,Original Research ,ischemia reperfusion injury ,Warm Ischemia Time ,Chemistry ,Postischämiesyndrom ,Complement activation ,Receptors, Complement ,Reperfusion injury ,medicine.anatomical_structure ,Reperfusion Injury ,Cytokines ,Kidney Diseases ,medicine.symptom ,lcsh:Immunologic diseases. Allergy ,medicine.medical_specialty ,Immunology ,Ischemia ,HO-1 ,Inflammation ,03 medical and health sciences ,AKI ,Internal medicine ,medicine ,Animals ,Anaphylatoxin ,ddc:610 ,cardiovascular diseases ,C3aR ,Complement system proteins ,Receptor, Anaphylatoxin C5a ,C5aR ,urogenital system ,medicine.disease ,%22">Komplement ,030104 developmental biology ,Endocrinology ,lcsh:RC581-607 ,030215 immunology - Abstract
Background: Ischemia reperfusion injury (IRI) plays a major role in solid organ transplantation. The length of warm ischemia time is critical for the extent of tissue damage in renal IRI. In this experimental study we hypothesized that local release of labile heme in renal tissue is triggered by the duration of warm ischemia (15 vs. 45 min IRI) and mediates complement activation, cytokine release, and inflammation. Methods: To induce IRI, renal pedicle clamping was performed in male C57BL/6 mice for short (15 min) or prolonged (45 min) time periods. Two and 24 h after experimental ischemia tissue injury labile heme levels in the kidney were determined with an apo-horseradish peroxidase assay. Moreover, renal injury, cytokines, and C5a and C3a receptor (C5aR, C3aR) expression were determined by histology, immunohistochemistry and qPCR, respectively. In addition, in vitro studies stimulating bone marrow-derived macrophages with LPS and the combination of LPS and heme were performed and cytokine expression was measured. Results: Inflammation and local tissue injury correlated with the duration of warm ischemia time. Labile heme concentrations in renal tissue were significantly higher after prolonged (45 min) as compared to short (15 min) IRI. Notably, expression of the inducible heme-degrading enzyme heme oxygenase-1 (HO-1) was up-regulated in kidneys after prolonged, but not after short IRI. C5aR, the pro-inflammatory cytokines IL-6 and TNF-alpha as well as pERK were up-regulated after prolonged, but not after short ischemia times. Consecutively, neutrophil infiltration and up-regulation of pro-fibrotic cytokines such as CTGF and PAI were more pronounced in prolonged IRI in comparison to short IRI. In vitro stimulation of macrophages with LPS revealed that IL-6 expression was enhanced in the presence of heme. Finally, administration of the heme scavenger human serum albumin (HSA) reduced the expression of pro-inflammatory cytokines, C3a receptor and improved tubular function indicated by enhanced alpha 1 microglobulin (A1M) absorption after IRI. Conclusions: Our data show that prolonged duration of warm ischemia time increased labile heme levels in the kidney, which correlates with IRI-dependent inflammation and up-regulation of anaphylatoxin receptor expression.
- Published
- 2019