Ischemic Kidney Research Articles

Female sex hormones inversely regulate acute kidney disease susceptibility throughout life.

While epidemiological and experimental studies have demonstrated kidney-protective effects of estrogen and female sex in adulthood, some epidemiological data showed deterioration of kidney function during puberty when estrogen production increases. However, molecular mechanisms explaining these conflicting phenomena remain unknown. Here, we showed that the pubertal sex hormone surge in female mice increases susceptibility to kidney ischemia reperfusion injury partly via downregulation of insulin-like growth factor 1 receptor (IGF-1R) expression in proximal tubules. Adult mice ovariectomized pre-pubertally (at postnatal day 21) showed strong tolerance to kidney ischemia, which was partly reversed by the administration of 17β-estradiol, while adult mice ovariectomized post-pubertally (at 8 weeks of age) were vulnerable to kidney ischemia. Kidney tubular IGF-1R protein expression decreased during postnatal growth but was highly expressed in adult mice ovariectomized pre-pubertally and in infant mice, which might be partly explained by different expression of an E3 ligase (MDM2) of IGF-1R. Mice deficient of Igf-1r in proximal tubules (iIGF-1RKO mice) during postnatal kidney growth showed increased susceptibility to ischemic injury. RNA-seq and western blotting analysis using proximal tubular cells from pre-pubertally ovariectomized iIGF-1RKO and control mice revealed altered expression of cell cycle-associated molecules such as cyclin D1. These results suggest that Igf-1r deletion during postnatal growth renders proximal tubular cells susceptible to ischemia possibly via altered cell cycle regulation. Thus, our findings provide evidence that exposure to pubertal sex hormones leads to increased susceptibility to kidney ischemia, which is partly mediated by modulation of IGF-1R signaling.

Molecular Signatures of Reperfusion in Ischemic Donor Kidneys: Distinguishing Rejection and Nonrejection Risk Genotypes through Single Nuclear RNA Sequencing

Molecular Signatures of Reperfusion in Ischemic Donor Kidneys: Distinguishing Rejection and Nonrejection Risk Genotypes through Single Nuclear RNA Sequencing

Diverse phenotype of Ménière’s disease associated with family history, thyroid disorder, migraine and associated disorders

ObjectiveTo better understand the clinical phenotype of Ménière’s disease (MD), we examined family history, thyroid disorder, migraine, and associated disorders in complaints of people living with MD. MethodWe designed the study as a retrospective and examined data gathered from 912 participants with MD. Their data were originally collected by the Finnish Ménière Federation (FMF). The survey data included individual case histories for environmental factors, comorbidities, disease-specific complaints, impact-related questions, cognitive complaints, health-related quality of life (HRQoL), and sense of coherence (SOC). ResultsWe observed significant differences between those with and without sporadic occurrence, family history, thyroid disorder, and migraine-associated complaints. Family history explained 20% of variability in patient complaints. Patients with a family history of MD whose disease started at younger age experienced balance problems, more severe vertigo spells, more severe vestibular drop attacks (VDA), and less nausea, although they had good SOC. Thyroid disorder explained 14% of variability in patient complaints. MD patients with a thyroid disorder comorbidity suffered more often from constant dizziness, balance problems, greater impact of hearing problems, cognitive complaints, and poor HRQoL. Migraine explained 12% of variability in patients’ complaints and was associated with poor SOC and cognitive balance problems. MD patients with both thyroid disorder and migraine used antidepressants more often than other groups. Logistic regression analysis showed comorbidities of ischemic brain disorder (among 7.1%), kidney insufficiency (among 1.2%), and diabetes (among 7.3%) had statistically significant but restricted association with balance and gait problems, VDA, and reduced HRQoL. ConclusionsFamily history of MD and thyroid disorder or migraine comorbidities in MD influence the complaint pattern and partially explain complex symptom profiles, including symptoms of cognitive problems. Confounders play a minimal role in complaint profile and impact of MD whereas comorbidities influence the complaint structure and partly explain the complex symptom profile in MD.

Tertiary Lymphoid Structures and Late-Stage Lymphangiogenesis at Very-Late Time Points following Ischemic Kidney Injury

Tertiary Lymphoid Structures and Late-Stage Lymphangiogenesis at Very-Late Time Points following Ischemic Kidney Injury

Mitochondrial Function and Resistance to Oxidative Stress in the Kidney during Pregnancy.

We demonstrated that the serum of pregnant rats increases viability of kidney epithelial cells and promotes their proliferation. The intensity of oxidative stress in the kidneys was also reduced during pregnancy, but only in rats that were not exposed to acute ischemic kidney injury. This decrease in oxidative stress was not associated with changes in transmembrane mitochondrial potential, the size of mitochondria, time of opening of mitochondrial permeability transition pore (mPTP), mitochondrial respiration rate, antioxidant activity, or nitric oxide level.

MAFB in Macrophages Regulates Prostaglandin E2-Mediated Lipid Mediator Class Switch through ALOX15 in Ischemic Acute Kidney Injury.

Monocytes and macrophages express the transcription factor MAFB (V-maf musculoaponeurotic fibrosarcoma oncogene homolog B) and protect against ischemic acute kidney injury (AKI). However, the mechanism through which MAFB alleviates AKI in macrophages remains unclear. In this study, we induced AKI in macrophage lineage-specific Mafb-deficient mice (C57BL/6J) using the ischemia-reperfusion injury model to analyze these mechanisms. Our results showed that MAFB regulates the expression of Alox15 (arachidonate 15-lipoxygenase) in macrophages during ischemic AKI. The expression of ALOX15 was significantly decreased at the mRNA and protein levels in macrophages that infiltrated the kidneys of macrophage-specific Mafb-deficient mice at 24 h after ischemia-reperfusion injury. ALOX15 promotes the resolution of inflammation under acute conditions by producing specialized proresolving mediators by oxidizing essential fatty acids. Therefore, MAFB in macrophages promotes the resolution of inflammation in ischemic AKI by regulating the expression of Alox15. Moreover, MAFB expression in macrophages is upregulated via the COX-2/PGE2/EP4 pathway in ischemic AKI. Our invitro assay showed that MAFB regulates the expression of Alox15 under the COX-2/PGE2/EP4 pathway in macrophages. PGE2 mediates the lipid mediator (LM) class switch from inflammatory LMs to specialized proresolving mediators. Therefore, MAFB plays a key role in the PGE2-mediated LM class switch by regulating the expression of Alox15. Our study identified a previously unknown mechanism by which MAFB in macrophages alleviates ischemic AKI and provides new insights into regulating the LM class switch in acute inflammatory conditions.

Identification and validation of leukemia inhibitory factor as a protective factor in ischemic acute kidney injury

BackgroundIschemia-reperfusion injury (IRI) is a common pathophysiological mechanism of acute kidney injury (AKI). There is an urgent need for a more comprehensive analysis of its underlying mechanisms. Materials and methodsThe RNA-sequencing dataset GSE153625 was used to examine differentially expressed genes (DEGs) of kidney tissues in IRI-AKI mice compared with sham mice. We used 10 algorithms provided by cytohubba plugin and four external datasets (GSE192532, GSE52004, GSE98622, and GSE185383) to screen for hub genes. The IRI-AKI mouse model with different reperfusion times was established to validate the expression of hub gene in the kidneys. HK-2 cells were cultured in vitro under hypoxia/reoxygenation (H/R) conditions, via transfection with si-LIF or supplementation with the LIF protein to explore the function of the LIF gene. ResultsWe screened a total of 1,540 DEGs in the IRI group compared with the sham group and identified that the LIF hub gene may play potential roles in IRI-AKI. LIF was markedly upregulated in the kidney tissues of IRI-AKI mice, as well as in HK-2 cells grown under H/R conditions. The knockdown of LIF aggravated apoptosis and oxidative stress (OS) injury under H/R conditions. Administration of the LIF protein rescued the effects of si-LIF, alleviating cellular apoptosis and OS. ConclusionThese findings indicate an important role of the LIF gene in term of regulating apoptosis and OS in the early phases of IRI-AKI. Targeting LIF may therefore represent a promising therapeutic strategy for IRI-AKI.

228.2: Efficacy of organ preservation at 22°C with extracellular-type preservation solutions in 2-hour warm ischemic kidney - Evaluation using a renal transplant model in MHC-inbred CLAWN miniature swine.

228.2: Efficacy of organ preservation at 22°C with extracellular-type preservation solutions in 2-hour warm ischemic kidney - Evaluation using a renal transplant model in MHC-inbred CLAWN miniature swine.

228.5: Multi-omics identify PDK4 as a novel therapeutic target for kidney ischemia reperfusion.

228.5: Multi-omics identify PDK4 as a novel therapeutic target for kidney ischemia reperfusion.

ST2 + T-Regulatory Cells in Renal Inflammation and Fibrosis after Ischemic Kidney Injury.

Inflammation is a major cause of kidney injury. The Interleukin (IL)-1 family cytokine IL-33 is released from damaged cells and modulates the immune response through its receptor ST2 expressed on many cell types, including regulatory T-cells (Tregs). While a proinflammatory role of IL-33 has been proposed, exogenous IL-33 expanded Tregs and suppressed renal inflammation. However, the contribution of endogenous IL-33/ST2 for the role of Tregs in the resolution of kidney injury has not been investigated. We used murine renal ischemia-reperfusion injury and kidney organoids to delineate the role of the ST2 and amphiregulin (AREG) specifically in Treg cells using targeted deletion. Bulk and single-cell RNA sequencing was performed on flow-sorted Tregs from spleen and CD4 T-cells from post-ischemic kidneys respectively. The protective role of ST2-sufficient Tregs was analyzed using a novel co-culture system of syngeneic kidney organoids and Treg cells under hypoxic conditions. Bulk RNA-sequencing of splenic and single-cell-RNA-sequencing of kidney T-cells showed that ST2+ Tregs are enriched for genes related to Treg proliferation and function. Genes for reparative factors such as AREG were also enriched in ST2+ Tregs. Treg-specific deletion of ST2 or AREG exacerbated kidney injury and fibrosis in the unilateral ischemia reperfusion injury model. In co-culture studies, WT but not ST2-deficient Tregs preserved the hypoxia-induced loss of kidney-organoid viability, which was restored by AREG supplementation. Our study identified the role of the IL-33/ST2 pathway in Tregs for resolution of kidney injury. The transcriptome of ST2+ Tregs was enriched for reparative factors including AREG. Lack of ST2 or AREG in Tregs worsened kidney injury. Tregs protected kidney organoids from hypoxia in ST2 and AREG-dependent manner. Thus Treg-based approaches could be of benefit for resolution of renal injury.

A comparative study of the efficiency of mitochondria-targeted antioxidants MitoTEMPO and SKQ1 under oxidative stress

MitoTEMPO (MT) and Visomitin (SKQ1) are regareded as mitochondria-targeted antioxidants, which inhibit production of mitochondrial reactive oxygen species (ROS). However, the differences in function between MT and SKQ1 remain unexplored. Herein, we investigated the differential potency of MT and SKQ1 in mitigating oxidative stress under different conditions. The results indicated that high levels of SKQ1 induced cell death. The appropriate concentrations of MT and SKQ1 can prevent or rescue cell damage triggered by hydrogen peroxide (H2O2) and menadione (MEN). MT and SKQ1 reduced ROS levels and reversed the down-regulation of antioxidant defence genes and enzymes. These effects can alleviate the damage to lipids, proteins, and deoxyribonucleic acid (DNA) caused by oxidative stress and restore adenosine 5′ triphosphate (ATP) generation. Subsequently, we found that MT administration in ischemic reperfusion kidney injury in mice provided superior renal protection compared to SKQ1, as evidenced by reduced plasma levels of kidney injury markers, improved renal morphology, decreased apoptosis, restored mitochondrial function, and enhanced antioxidant capacity. Overall, our findings suggest that MT is safer and has greater potential than SKQ1 as a therapeutic agent to mitigate oxidative stress damage or oxidative renal injury.

Remote liver ischemic preconditioning protects against renal ischemia/reperfusion injury via phosphorylation of extracellular signal-regulated kinases 1 and 2 in mice.

Perioperative acute kidney injury (AKI), which is mainly mediated by renal ischemia‒reperfusion (I/R) injury, is commonly observed in clinical practice. However, effective measures for preventing and treating this perioperative complication are still lacking in the clinic. Thus, we designed this study to examine whether remote liver ischemic preconditioning (RLIPC) has a protective effect on damage caused by renal I/R injury. In a rodent model, 30 mice were divided into five groups to assess the effects of RLIPC and ERK1/2 inhibition on AKI. The groups included the sham-operated (sham), kidney ischemia and reperfusion (CON), remote liver ischemic preconditioning (RLIPC), CON with the ERK1/2 inhibitor U0126 (CON+U0126), and RLIPC with U0126 (RLIPC+U0126). RLIPC consisted of 4 liver ischemia cycles before renal ischemia. Renal function and injury were assessed through biochemical assays, histology, cell apoptosis and protein phosphorylation analysis. RLIPC significantly mitigated renal dysfunction, tissue damage, inflammation, and apoptosis caused by I/R, which was associated with ERK1/2 phosphorylation. Furthermore, ERK1/2 inhibition with U0126 negated the protective effects of RLIPC and exacerbated renal injury. To summarize, we demonstrated that RLIPC has a strong renoprotective effect on kidneys post I/R injury and that this effect may be mediated by phosphorylation of ERK1/2.

Inhibition of complement factor C5a or C5aR for cholesterol crystal embolism–related vascular thrombosis with microvascular injury and its consequences

Cholesterol crystal embolism (CCE) implies immunothrombosis, tissue necrosis, and organ failure but no specific treatments are available. As CCE involves complement activation, we speculated that inhibitors of the C5a/C5aR axis would be sufficient to attenuate the consequences of CCE like that with systemic vasculitis. Cholesterol microcrystal injection into the kidney artery of wildtype mice initiated intra-kidney immunothrombosis within a few hours followed by a sudden drop of glomerular filtration rate and ischemic kidney necrosis after 24 hours. Genetic deficiency of either C3 or C5aR prevented immunothrombosis, glomerular filtration rate drop, and ischemic necrosis at 24 hours as did preemptive treatment with inhibitors of either C5a or C5aR. Delayed C5a blockade after crystal injection still resolved crystal clots and prevented all consequences. Thus, selective blockade of C5a or C5aR is sufficient to attenuate the consequences of established CCE and prospective inhibition in high-risk patients may be clinically feasible and safe.

Pseudogene GSTM3P1 derived long non-coding RNA promotes ischemic acute kidney injury by target directed microRNA degradation of kidney-protective mir-668

Long non-coding RNAs (lncRNAs) are a group of epigenetic regulators that have been implicated in kidney diseases including acute kidney injury (AKI). However, very little is known about the specific lncRNAs involved in AKI and the mechanisms underlying their pathologic roles. Here, we report a new lncRNA derived from the pseudogene GSTM3P1, which mediates ischemic AKI by interacting with and promoting the degradation of mir-668, a kidney-protective microRNA. GSTM3P1 and its mouse orthologue Gstm2-ps1 were induced by hypoxia in cultured kidney proximal tubular cells. In mouse kidneys, Gstm2-ps1 was significantly upregulated in proximal tubules at an early stage of ischemic AKI. This transient induction of Gstm2-ps1 depends on G3BP1, a key component in stress granules. GSTM3P1 overexpression increased kidney proximal tubular apoptosis after ATP depletion, which was rescued by mir-668. Notably, kidney proximal tubule-specific knockout of Gstm2-ps1 protected mice from ischemic AKI, as evidenced by improved kidney function, diminished tubular damage and apoptosis, and reduced kidney injury biomarker (NGAL) induction. To test the therapeutic potential, Gstm2-ps1 siRNAs were introduced into cultured mouse proximal tubular cells or administered to mice. In cultured cells, Gstm2-ps1 knockdown suppressed ATP depletion-associated apoptosis. In mice, Gstm2-ps1 knockdown ameliorated ischemic AKI. Mechanistically, both GSTM3P1 and Gstm2-ps1 possessed mir-668 binding sites and downregulated the mature form of mir-668. Specifically, GSTM3P1 directly bound to mature mir-668 to induce its decay via target-directed microRNA degradation. Thus, our results identify GSTM3P1 as a novel lncRNA that promotes kidney tubular cell death in AKI by binding mir-668 to inducing its degradation.

The Total Denervation of the Ischemic Kidney Induces Differential Responses in Sodium Transporters' Expression in the Contralateral Kidney in Goldblatt Rats.

The Goldblatt model of hypertension (2K-1C) in rats is characterized by renal sympathetic nerve activity (rSNA). We investigated the effects of unilateral renal denervation of the clipped kidney (DNX) on sodium transporters of the unclipped kidneys and the cardiovascular, autonomic, and renal functions in 2K-1C and control (CTR) rats. The mean arterial pressure (MAP) and rSNA were evaluated in experimental groups. Kidney function and NHE3, NCC, ENaCβ, and ENaCγ protein expressions were assessed. The glomerular filtration rate (GRF) and renal plasma flow were not changed by DNX, but the urinary (CTR: 0.0042 ± 0.001; 2K-1C: 0.014 ± 0.003; DNX: 0.005 ± 0.0013 mL/min/g renal tissue) and filtration fractions (CTR: 0.29 ± 0.02; 2K-1C: 0.51 ± 0.06; DNX: 0.28 ± 0.04 mL/min/g renal tissue) were normalized. The Na+/H+ exchanger (NHE3) was reduced in 2K-1C, and DNX normalized NHE3 (CTR: 100 ± 6; 2K-1C: 44 ± 14, DNX: 84 ± 13%). Conversely, the Na+/Cl- cotransporter (NCC) was increased in 2K-1C and was reduced by DNX (CTR: 94 ± 6; 2K-1C: 144 ± 8; DNX: 60 ± 15%). In conclusion, DNX in Goldblatt rats reduced blood pressure and proteinuria independently of GRF with a distinct regulation of NHE3 and NCC in unclipped kidneys.

Disruption in glutathione metabolism and altered energy production in the liver and kidney after ischemic acute kidney injury in mice

Acute kidney injury (AKI) is a systemic disease that affects energy metabolism in various remote organs in murine models of ischemic AKI. However, AKI-mediated effects in the liver have not been comprehensively assessed. After inducing ischemic AKI in 8–10-week-old, male C57BL/6 mice, mass spectrometry metabolomics revealed that the liver had the most distinct phenotype 24 h after AKI versus 4 h and 7 days. Follow up studies with in vivo [13C6]-glucose tracing on liver and kidney 24 h after AKI revealed 4 major findings: (1) increased flux through glycolysis and the tricarboxylic (TCA) cycle in both kidney and liver; (2) depleted hepatic glutathione levels and its intermediates despite unchanged level of reactive oxygen species, suggesting glutathione consumption exceeds production due to systemic oxidative stress after AKI; (3) hepatic ATP depletion despite unchanged rate of mitochondrial respiration, suggesting increased ATP consumption relative to production; (4) increased hepatic and renal urea cycle intermediates suggesting hypercatabolism and upregulation of the urea cycle independent of impaired renal clearance of nitrogenous waste. Taken together, this is the first study to describe the hepatic metabolome after ischemic AKI in a murine model and demonstrates that there is significant liver-kidney crosstalk after AKI.

LIM Zinc Finger Domain Containing 1 Risk Genotype of Recipient Is Associated with Renal Tubular Inflammation in Kidney Transplantation.

Homozygosity for LIMS1 rs893403-GG genotype is linked to an increased risk of allograft rejection after kidney transplantation. Ischemia-reperfusion of the kidney allograft leads to long term infiltration of activated and effector-memory T lymphocytes and resulting in rejection and long-term fibrosis. However, the genotype, LIMS1 expression under ischemic conditions and the long-term histopathological relationships remain ill-defined. We examined the impact of the recipient's LIMS1-rs893403 genotype with transplant kidney histopathology. The association of the LIMS1-rs893403 genotype and LIMS1 and GCC2 mRNA expression in ischemic donor kidneys were also examined. Recipients who underwent transplant kidney biopsy were genotyped for the LIMS1-rs893403 variant and associated deletion. Histopathological findings were compared between recipients with LIMS1 risk and non-risk genotypes. Real-time PCR and immunofluorescence staining for LIMS1 and GCC2 expression were performed in non-utilized donor kidneys. Demographic, clinical, and treatment characteristics and the histopathological diagnosis were similar between recipients with rs893403 GG and AA/AG genotype. The Banff tubulitis score was higher in GG recipients (n = 24) compared to AA/AG (n = 86) recipients (1.42 ± 0.65 vs. 1.12 ± 0.66, p = 0.03). Ischemic kidneys with GG showed higher LIMS1 and GCC2 mRNA expression than kidneys with AG. Kidneys with rs893403-GG had higher tubular LIMS1 and GCC2 immunohistochemical staining compared to kidneys with rs893403-AG. Our data supports the role of the LIMS1 locus in kidney transplant rejection, particularly in lymphocyte infiltration into the internal aspect of the tubular basement membranes. Increased LIMS1 and GCC2 expression in ischemic donor kidneys with the GG genotype require further studies.

Multi-omics analysis of renal vein serum with Ischemia-Reperfusion injury

BackgroundAcute kidney injury (AKI) is frequently caused by renal ischemia–reperfusion injury (IRI). Identifying potential renal IRI disease biomarkers would be useful for evaluating AKI severity. ObjectiveWe used proteomics and metabolomics to investigate the differences in renal venous blood between ischemic and healthy kidneys in an animal model by identifying differentially expressed proteins (DEPs) and differentially expressed protein metabolites (DEMs). MethodsNine pairs of renal venous blood samples were collected before and at 20, 40, and 60 min post ischemia. The ischemia time of Group A, B and C was 20,40 and 60 min. The proteome and metabolome of renal venous blood were evaluated to establish the differences between renal venous blood before and after ischemia. ResultsWe identified 79 common DEPs in all samples of Group A, 80 in Group B, and 131 in Group C. Further common DEPs among all three groups were Tyrosineprotein kinase, GPR15LG, KAZALD1, ADH1B. We also identified 81, 64, and 83 common DEMs in each group respectively, in which 30 DEMs were further common to all groups. Bioinformatic analysis of the DEPs and DEMs was conducted. ConclusionThis study demonstrated that different pathological processes occur during short- and long-term renal IRI. Tyrosine protein kinase, GPR15LG, Kazal-type serine peptidase inhibitor domain 1, and all-trans-retinol dehydrogenase are potential biomarkers of renal IRI.

Double-negative T cells have a reparative role after experimental severe ischemic acute kidney injury.

T cells mediate organ injury and repair. A proportion of unconventional kidney T cells called double-negative (DN) T cells (TCR+ CD4- CD8-), with anti-inflammatory properties, were previously demonstrated to protect from early injury in moderate experimental acute kidney injury (AKI). However, their role in repair after AKI has not been studied. We hypothesized that DN T cells mediate repair after severe AKI. C57B6 mice underwent severe (40 min) unilateral ischemia-reperfusion injury (IRI). Kidney DN T cells were studied by flow cytometry and compared with gold-standard anti-inflammatory CD4+ regulatory T cells (Tregs). In vitro effects of DN T cells and Tregs on renal tubular epithelial cell (RTEC) repair after injury were quantified with live-cell analysis. DN T cells, Tregs, CD4, or vehicle were adoptively transferred after severe AKI. Glomerular filtration rate (GFR) was measured using fluorescein isothiocyanate (FITC)-sinistrin. Fibrosis was assessed with Masson's trichrome staining. Profibrotic genes were measured with qRT-PCR. Percentages and the numbers of DN T cells substantially decreased during repair phase after severe AKI, as well as their activation and proliferation. Both DN T cells and Tregs accelerated RTEC cell repair in vitro. Post-AKI transfer of DN T cells reduced kidney fibrosis and improved GFR, as did Treg transfer. DN T cell transfer lowered transforming growth factor (TGF)β1 and α-smooth muscle actin (αSMA) expression. DN T cells reduced effector-memory CD4+ T cells and IL-17 expression. DN T cells undergo quantitative and phenotypical changes after severe AKI, accelerate RTEC repair in vitro as well as improve GFR and renal fibrosis in vivo. DN T cells have potential as immunotherapy to accelerate repair after AKI.NEW & NOTEWORTHY Double-negative (DN) T cells (CD4- CD8-) are unconventional kidney T cells with regulatory abilities. Their role in repair from acute kidney injury (AKI) is unknown. Kidney DN T cell population decreased during repair after ischemic AKI, in contrast to regulatory T cells (Tregs) which increased. DN T cell administration accelerated tubular repair in vitro, while after severe in vivo ischemic injury reduced kidney fibrosis and increased glomerular filtration rate (GFR). DN T cell infusion is a potential therapeutic agent to improve outcome from severe AKI.

En Bloc Simultaneous Liver–Kidney Transplantation Compared to the Traditional Technique: Results From a Single Center

Introduction: Simultaneous liver-kidney transplantation is indicated for patients with concomitant end-stage liver disease and end-stage renal disease. The traditional technique involves separate implantations of the liver and the kidney. In the en bloc approach, the liver is recovered en bloc with the right kidney and the donor renal artery is anastomosed to the donor splenic artery.Objective: To compare the outcomes of the traditional and en bloc techniques for simultaneous liver-kidney transplantation in a single center.Methods: Single-center retrospective study involving all adult patients who underwent simultaneous liver-kidney transplantation with brain-dead donors from January/2017 to December/2022.Results: A total of 15 patients were included, being 10 transplanted with the traditional technique and 5 with the en bloc one. Patients in the en bloc group presented higher body mass index, shorter cold and total kidney ischemia time, shorter overall surgical time and longer kidney ischemia time (29.07 vs 23.20kg/m2, p=0.048; 560 vs 880min, p=0.026; 615 vs 908min, p=0.025; 405 vs 485min, p =0.046; 46 vs 33.5min, p=0.027, respectively). Ureteroneocystostomy was performed in 2 patients of the en bloc group and ureteroureterostomy in the remaining 3 patients. One patient in the en bloc group presented stenosis of renal artery anastomosis and underwent percutaneous angioplasty. This same patient eventually developed late urinary fistula. In the traditional technique group, there were two cases of renal vein thrombosis and one of ureteral stenosis.Conclusion: Compared to the traditional technique, the en bloc approach is feasible and safe, reducing the total surgical and kidney ischemia times.