Renal Ischemia-reperfusion Research Articles

MiR-199a-5p aggravates renal ischemia-reperfusion and transplant injury by targeting AKAP1 to disrupt mitochondrial dynamics.

Renal ischemia-reperfusion injury (IRI) is a complex pathophysiological process and a major cause of delayed graft function (DGF) after transplantation. MicroRNA (miRNA) has important roles in the pathogenesis of IRI and may represent promising therapeutic targets for mitigating renal IRI. miRNA sequencing was performed to profile microRNA expression in mouse kidneys after cold storage and transplantation (CST). Lentivirus incorporating a miR-199a-5p modulator was injected into mouse kidney in situ before syngenetic transplantation and unilateral IRI to determine the effect of miR-199a-5p in vivo. miR-199a-5p mimic or inhibitor was transfected cultured tubular cells before ATP depletion recovery treatment to examine the role of miR-199a-5p in vitro. Sequencing data and microarray showed upregulation of miR-199a-5p in mice CST and human DGF samples. Lentivirus incorporating a miR-199a-5p mimic aggravated renal IRI, and protective effects were obtained with a miR-199a-5p inhibitor. Treatment with the miR-199a-5p inhibitor ameliorated graft function loss, tubular injury, and immune response after CST. In vitro experiments revealed exacerbation of mitochondria dysfunction upon ATP depletion and repletion model in the presence of the miR-199a-5p mimic, whereas dysfunction was attenuated when the miR-199a-5p inhibitor was applied. miR-199a-5p was shown to target A-kinase anchoring protein 1 (AKAP1) by double luciferase assay and miR-199a-5p activation reduced dynamin-related protein 1 (Drp1)-s637 phosphorylation and mitochondrial length. Overexpression of AKAP1 preserved Drp1-s637 phosphorylation and reduced mitochondrial fission. miR-199a-5p activation reduced AKAP1 expression, promoted Drp1-s637 dephosphorylation, aggravated the disruption of mitochondrial dynamics, and contributed to renal IRI.NEW & NOTEWORTHY This study identifies miR-199a-5p as a key regulator in renal ischemia-reperfusion injury through microRNA sequencing in mouse models and human delayed graft function. miR-199a-5p worsens renal IRI by aggravating graft dysfunction, tubular injury, and immune response, while its inhibition shows protective effects. miR-199a-5p downregulates A-kinase anchoring protein 1 (AKAP1), reducing dynamin-related protein 1 (Drp1)-s637 phosphorylation, increasing mitochondrial fission, and causing dysfunction. Targeting the miR-199a-5p/AKAP1/Drp1 axis offers therapeutic potential for renal IRI, as AKAP1 overexpression preserves mitochondrial integrity by maintaining Drp1-s637 phosphorylation.

Engineering of phosphatidylserine-targeting ROS-responsive polymeric prodrug for the repair of ischemia-reperfusion-induced acute kidney injury.

Ischemia-reperfusion-induced acute kidney injury (IR-AKI) commonly occurs in situations such as hemorrhagic shock, kidney transplantation, and cardiovascular surgery. As one of the significant causes of AKI, IR-AKI is characterized by its high incidence and mortality rates. Currently, effective inflammation control is the key for the treatment of IR-AKI. In this study, we developed an ROS-responsive polymeric prodrugs (Zn-D/DTH) which could target the externalized PS of apoptotic cells, and then responsively released HDM (anti-inflammatory peptides) in the presence of intracellular ROS. Zn-D/DTH effectively ameliorated renal function and mitigated pathological alterations such as the loss of the brush border, tubular dilation, and accumulation of cellular debris within the tubular lumens. Furthermore, Zn-D/DTH greatly reduced the generation of pro-inflammatory factors like IL-6, COX-2, and iNOS in renal tissues, suggesting its protective role largely stems from suppression of the inflammatory response. Additional mechanism exploration revealed that Zn-D/DTH markedly decreased the expression levels of TLR4 and MyD88, as well as the phosphorylation of NF-κB in the damaged kidneys. This, in turn, reduced the number of apoptotic tubular cells and the activity of Caspase 9 and Caspase 3 caused by ischemia-reperfusion. Additionally, Zn-D/DTH treatment showed improvement in the long-term renal damage and fibrosis induced by ischemia-reperfusion. The experimental outcomes indicated that Zn-D/DTH attenuated renal ischemia-reperfusion injury and delayed the transition from acute kidney injury to chronic kidney disease by downregulating the TLR4/MyD88/NF-κB signaling pathway and reducing the expression of apoptotic caspases, thereby inhibiting inflammation and reducing cell apoptosis.

Nephroprotective role of resveratrol in renal ischemia-reperfusion injury: a preclinical study in Sprague-Dawley rats.

Renal ischemia-reperfusion injury (IRI) is a significant contributor to renal dysfunction, acute kidney injury (AKI), and associated morbidity and mortality. Resveratrol, a polyphenol and phytoalexin, is known for its anti-inflammatory, antioxidant, and anti-cancer properties. This study investigates the nephroprotective potential of resveratrol in a rat model of renal IRI. Twenty-eight male Sprague-Dawley rats were divided into four groups: Sham, IRI, DMSO, and Resveratrol. The Sham group underwent identical procedures without renal pedicle clamping, while the IRI group experienced 30min of ischemia followed by 2h of reperfusion. The DMSO group received dimethyl sulfoxide (DMSO) intraperitoneally 30min before ischemia, and the Resveratrol group received 30mg/kg resveratrol intraperitoneally 30min before ischemia. Biochemical parameters (Urea, creatinine, IL-1β, NF-κβ, SOD, GSH, Bcl-2, and caspase-3) and histopathological changes were assessed. IRI caused a substantial increase in serum creatinine, Urea, IL-1β, NF-κβ, and caspase-3 levels, while simultaneously decreasing SOD, GSH, and Bcl-2 levels. Resveratrol treatment mitigated these effects by lowering inflammatory and apoptotic markers, enhancing antioxidant defenses, and improving histological outcomes. Resveratrol demonstrates significant nephroprotective effects in renal IRI, primarily through its antioxidant, anti-inflammatory, and anti-apoptotic properties.

GALNT3 in Ischemia-Reperfusion Injury of the Kidney.

Damages to subcellular organelles, such as mitochondria and endoplasmic reticulum, are well-recognized in tubular cell injury and death in acute kidney injury (AKI). However, the changes and involvement of Golgi apparatus are much less known. Here, we report the regulation and role of N-acetylgalactosaminyltransferase-3 (GALNT3), a key enzyme for protein glycosylation in Golgi apparatus, in AKI. AKI was induced in mice by renal ischemia-reperfusion or cisplatin. In vitro, rat kidney proximal tubular cells were subjected to hypoxia/reoxygenation (H/R) injury. To determine the role of GALNT3, its specific inhibitor T3inh-1 was tested in mice, and the effects of GALNT3 overexpression as well as knockdown were examined in the rat renal proximal tubular cells. EGFR activation was induced by recombinant EGF or by overexpressing EGFR. GALNT3 was significantly decreased in both in vivo and in vitro models of AKI induced by renal ischemia-reperfusion and cisplatin. T3Inh-1, a specific GALNT3 inhibitor, exacerbated ischemic AKI and suppressed tubular cell proliferation in mice. Moreover, knockdown of GALNT3 increased apoptosis during H/R treatment in rat renal proximal tubular cells, while overexpression of GALNT3 attenuated H/R-induced apoptosis, further supporting a protective role of GALNT3. Mechanistically, GALNT3 contributed to O-glycosylation of epidermal growth factor receptor (EGFR) and associated EGFR signalling. Activation or overexpression of EGFR suppressed the pro-apoptotic effect of GALNT3 knockdown in H/R-treated rat renal proximal tubular cells. GALNT3 protected kidney tubular cells in AKI at least partially through O-glycosylation of EGFR.

SETDB1 targeting SESN2 regulates mitochondrial damage and oxidative stress in renal ischemia–reperfusion injury

BackgroundThe role of histone methyltransferase SETDB1 in renal ischemia–reperfusion (I/R) injury has not been explored yet. This study aims to investigate the potential mechanism of SETDB1 in regulating renal I/R injury and its impact on mitochondrial damage and oxidative stress.MethodsThe in vivo model of renal I/R in mice and the in vitro model of hypoxia/reoxygenation (H/R) in human renal tubular epithelial cells (HK-2) were constructed to detect the expression of SETDB1. Next, the specific inhibitor (R,R)-59 and knockdown viruses were used to inhibit SETDB1 and verify its effects on mitochondrial damage and oxidative stress. Chromatin immunoprecipitation (ChIP) and coimmunoprecipitation (CoIP) were implemented to explore the in-depth mechanism of SETDB1 regulating renal I/R injury.ResultsThe study found that SETDB1 had a regulatory role in mitochondrial damage and oxidative stress during renal I/R injury. Notably, SESN2 was identified as a target of SETDB1, and its expression was under the influence of SETDB1. Besides, SESN2 mediated the regulation of SETDB1 on renal I/R injury. Through deeper mechanistic studies, we uncovered that SETDB1 collaborates with heterochromatin HP1β, facilitating the labeling of H3K9me3 on the SESN2 promoter and impeding SESN2 expression.ConclusionsThe SETDB1/HP1β-SESN2 axis emerges as a potential therapeutic strategy for mitigating renal I/R injury.

Regulation of renal ischemia-reperfusion injury and tubular epithelial cell ferroptosis by pparγ m6a methylation: mechanisms and therapeutic implications

This study aimed to elucidate the role and underlying mechanisms of Peroxisome proliferator-activated receptor gamma (PPARγ) and its m6A methylation in renal ischemia-reperfusion (I/R) injury and ferroptosis of tubular epithelial cells (TECs). High-throughput transcriptome sequencing was performed on renal tissue samples from I/R injury models and sham-operated mice, complemented by in vivo and in vitro experiments focusing on the PPARγ activator Rosiglitazone and the manipulation of METTL14 and IGF2BP2 expression. Key evaluations included renal injury assessment, ferroptosis indicator measurement, and m6A methylation analysis of PPARγ. Our findings highlight the critical role of the PPARγ pathway and ferroptosis in renal I/R injury, with Rosiglitazone ameliorating renal damage and TEC ferroptosis. METTL14-mediated m6A methylation of PPARγ, dependent on IGF2BP2, emerged as a pivotal regulator of PPARγ expression, renal injury, and ferroptosis. This study reveals that PPARγ m6A methylation, orchestrated by METTL14 through an IGF2BP2-dependent mechanism, plays a crucial role in mitigating renal I/R injury and TEC ferroptosis. These insights offer promising avenues for therapeutic strategies targeting acute kidney injury.

Overexpression of miR-451a Aggravates Renal Ischemia–Reperfusion Injury by Targeting KLF1-ACSL4 to Promote Ferroptosis

Ischemia–reperfusion injury (IRI) is a predominant factor leading to delayed graft function (DGF) following kidney transplantation. MicroRNAs (miRNAs) play a pivotal role in the pathogenesis of renal IRI, with ferroptosis being a critical driving force throughout the process. In this study, we utilized bioinformatics methods to construct a network diagram of differentially expressed miRNAs, transcription factors (TFs), and ferroptosis-related genes. An I/R-induced renal injury model in mice and an in vitro H/R-induced HK-2 cell injury model were established. Quantitative real-time PCR (qRT-PCR) and Western blot analysis were used to measure the mRNA and miRNA levels in cells and tissues. The MDA concentration, iron levels, and GSH concentration were measured to evaluate the ferroptosis levels. CCK-8 assays were performed to assess cell viability. Luciferase reporter assays were conducted to validate the downstream targets of miRNA, and chromatin immunoprecipitation assays were performed to verify the interaction between TFs and mRNAs. Both the in vivo and in vitro results demonstrate that miR-451a was significantly enriched in the IRI renal tissues and cells, exacerbating ferroptosis. MiR-451a was found to reduce the expression of Kruppel-like factor 1 (KLF1) by directly binding to the 3′UTR of KLF1 mRNA. Additionally, KLF1 was identified as a negative transcription factor for acyl-CoA synthetase long-chain family member 4 (ACSL4). We demonstrated that IRI induced the upregulation of miR-451a, which reduced KLF1 expression, thereby promoting ferroptosis by upregulating ACSL4 expression, ultimately aggravating IRI-induced renal damage.

NaHS protects brain, heart, and lungs as remote organs from renal ischemia/reperfusion-induced oxidative stress in male and female rats

Acute Kidney Injury (AKI) is frequently observed in hospitalized patients in intensive care units, often caused by renal ischemia-reperfusion injury (IRI). IRI disrupts the function of various ‘remote organs’ such as the lungs, pancreas, intestine, liver, heart, and brain through inflammation, oxidative stress, apoptosis, leukocyte infiltration, and increased urea and creatinine levels. Gender differences in renal IRI-induced injury are noted. H2S, an endogenous gaseous modulator, shows potential in vasodilation, bronchodilation, and hypotension and can regulate apoptosis, inflammation, angiogenesis, metabolism, and oxidative stress. This study aims to investigate the protective effects of NaHS on brain, heart, and lung injuries following renal IR and to assess the oxidative system status as a potential mechanism in male and female rats.Forty-eight Wistar rats were randomly divided into eight groups (n = 6): Control/Saline, Sham/Saline, IR/Saline, and IR/NaHS in both sexes. Forty-five minutes of bilateral renal ischemia followed by 24-hour reperfusion was induced in the IR groups. NaHS (100µM/Kg, IP) was administered 10 min before clamp release in treated groups. BUN, SCr, BUN/SCr, albuminuria, histopathology, and oxidative stress biomarkers of the brain, heart, and lung were assessed as remote organs. IR increased serum markers of renal function, albuminuria, malondialdehyde levels, and tissue injury scores while reducing nitrite levels and superoxide dismutase and glutathione peroxidase activities. NaHS treatment reversed the adverse effects of IR in remote organs in both sexes, although it showed limited improvement in renal function. Our findings demonstrate that NaHS has a beneficial effect on remote organ injury following renal IR by mitigating oxidative stress, with noted tissue-specific and gender-specific differences in response. These findings suggest NaHS as a potential therapeutic agent for mitigating multi-organ injury after renal IR, with effects varying by tissue and gender.

Prolonged Retention of Albumin Nanoparticles Alleviates Renal Ischemia-Reperfusion Injury through Targeted Pyroptosis.

Acute kidney injury (AKI) represents a prevalent and complex clinical event, characterized by irreversible damage to renal tubular epithelial cells and high intensive care unit (ICU) admission rates and mortality. The kidneys are highly susceptible to oxidative stress, inflammation, pyroptosis, and programmed cell death. Pyroptosis poses a significant risk, exacerbating the damage and inflammation of renal tubular cells. Disulfiram (DSF), an FDA-approved medication for alcohol cessation, inhibits the pyroptotic pore-forming protein Gasdermin-D (GSDMD), positioning it as a potential solution for emergency relief against an inflammatory response. However, current obstacles include poor water solubility, rapid metabolism, and off-target effects. Inspired by this discovery, bovine serum albumin (BSA), which has already entered clinical application, has been utilized to produce safe and long-lasting nanoparticles (BSA@DSF NPs), addressing the challenges posed by DSF's physicochemical properties. By targeting the GSDMD protein, the potent pro-inflammatory effects of pyroptosis were mitigated, leading to the alleviation of AKI induced by ischemia-reperfusion injury. This research offers a straightforward and efficient concept for treating AKI, potentially enhancing the transition to clinical practice.

Bidirectional Impact of Varying Severity of Acute Kidney Injury on Calcium Oxalate Stone Formation.

Acute Kidney Injury (AKI) is a prevalent renal disorder. The occurrence of AKI may promote the formation of renal calcium oxalate stones by exerting continuous effects on renal tubular epithelial cells. We aimed to delineate the molecular interplay between AKI and nephrolithiasis. A mild (20 min) and severe (30 min) renal ischemia-reperfusion injury model was established in mice. Seven days after injury, calcium oxalate stones were induced using glyoxylate (Gly) to evaluate the impact of AKI on the formation of kidney stones. Transcriptome sequencing was performed on tubular epithelial cells (TECs) to elucidate the relationship between AKI severity and kidney stones. Key transcription factors (TF) regulating differential gene transcription levels were identified using motif analysis, and pioglitazone, ginkgetin, and fludarabine were used for targeted therapy to validate key transcription factors as potential targets for kidney stone treatment. Severe AKI led to increased deposition of calcium oxalate crystals in renal, impaired kidney function, and upregulation of kidney stone-related gene expression. In contrast, mild AKI was associated with decreased crystal deposition, preserved kidney function, and downregulation of similar gene expression. Transcriptomic analysis revealed that genes associated with inflammation and cell adhesion pathways were significantly upregulated after severe AKI, while genes related to energy metabolism pathways were significantly upregulated after mild AKI. An integrative bioinformatic analysis uncovered a TF regulatory network within TECs, pinpointing that PKNOX1 was involved in the upregulation of inflammation-related genes after severe AKI, and inhibiting PKNOX1 function with Pioglitazone could simultaneously reduce the increase of calcium oxalate crystals after severe AKI in kidney. On the other hand, motif analysis also revealed the protective role of STAT1 in the kidneys after mild AKI, enhancing the function of STAT1 with Ginkgetin could reduce kidney stone formation, while the specific inhibitor of STAT1, Fludarabine, could eliminate the therapeutic effects of mild AKI on kidney stones. Inadequate repair of tubular epithelial cells after severe AKI increases the risk of kidney stone formation, with the upregulation of inflammation-related genes regulated by PKNOX1 playing a role in this process. Inhibiting PKNOX1 function can reduce kidney stone formation. Conversely, after mild AKI, effective cell repair through upregulation of STAT1 expression can protect TEC function, reduce stone formation, and activating STAT1 function can also achieve the goal of treating kidney stones.

USP15 inhibits hypoxia-induced IL-6 signaling by deubiquitinating and stabilizing MeCP2.

Methyl-CpG binding protein 2 (MeCP2) is an important X-linked DNA methylation reader and a key heterochromatin organizer. The expression level of MeCP2 is crucial, as indicated by the observation that loss-of-function mutations of MECP2 cause Rett syndrome, whereas an extra copy spanning the MECP2 locus results in MECP2 duplication syndrome, both being progressive neurodevelopmental disorders. Our previous study demonstrated that MeCP2 protein expression is rapidly induced by renal ischemia-reperfusion injury (IRI) and protects the kidney from IRI through transcriptionally repressing the interleukin-6 (IL-6)/signal transducer and activator of transcription 3 signaling pathway. However, the mechanisms underlying the upregulation of MeCP2 have remained elusive. Here, by using two hypoxia cell models, hypoxia and reoxygenation and cobalt chloride stimulation, we confirmed that the removal of lysine 48-linked ubiquitination from MeCP2 prevented its proteasome-dependent degradation under hypoxic conditions. Through unbiased screening based on a deubiquitinating enzymes library, we identified ubiquitin-specific protease 15 (USP15) as a stabilizer of MeCP2. Further studies revealed that USP15 could attenuate hypoxia-induced MeCP2 degradation by cleaving lysine 48-linked ubiquitin chains from MeCP2, primarily targeting its C-terminal domain. Consistently, USP15 inhibited hypoxia-induced signal transducer and activator of transcription 3 activation, resulting in reduced transcription of IL-6 downstream genes. In summary, our study reveals an important role for USP15 in the maintenance of MeCP2 stability and the regulation of IL-6 signaling.

Sivelestat Sodium Alleviates Ischemia-Reperfusion-Induced Acute Kidney Injury via Suppressing TLR4/Myd88/NF-κB Signaling Pathway in Mice.

We aim to detect the effects of sivelestat on renal ischemia-reperfusion associated with AKI and also explore the underlying mechanism. Mice, aged between 8 and 12weeks, were randomly allocated among four distinct groups, respectively normal saline sham group(C), normal saline surgery group(I), sivelestat (50 mg/kg) sham group(S), sivelestat (50 mg/kg) surgery group(SI) (n=6, each group). In the surgical groups, the renal pedicles of mice were clamped withnon-traumatic micro-aneurysm clamps, resulting in ischemia of the kidneys for 45minutes. This was followed by a period of reperfusion lasting 24hours. Sham group mice underwent the identical surgery produced without clamping renal pedicles. Mice blood was obtained from eyeballs, and Serum creatinine and blood urea nitrogen levels were measured. After a 24-hour period of reperfusion, the mice were euthanized, and their kidneys were gathered for various analyses, including Western Blot (WB) analysis, RT-PCR, immunofluorescence (IF), hematoxylin and eosin (H&E) staining, and Tunel assay. Pretreatments with sivelestat decreased renal Neutrophil elastase (NE), serum creatinine, and blood urea nitrogen levels after renal ischemia-reperfusion. Sivelestat also reduced histological damage and cell apoptosis in kidneys following ischemia-reperfusion injury (IRI). In addition, thesivelestat administrationdiminished the levels of mRNA expression of interleukin 6 (IL-6), Macrophage inflammatory protein-2 (MIP-2), monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor (TNF)-α in the kidneys during IRI.The kidney tissues of the SI group had significantly mitigated TLR4, Myd88, and NF-κB p-p65 protein expression levels compared to the I group (all P<0.05). We demonstrated a previously unidentified mechanism that sivelestat effectively attenuates AKI-induced renal dysfunction, possibly through suppressing the TLR4/Myd88/ NF-κB pathway.

Comparative Effects of Fedratinib and Upadacitinib on Renal Ischemia-Reperfusion Injury in Rat Models

Renal ischemia-reperfusion injury (RIRI) is a severe condition that frequently occurs following kidney transplantation or surgical procedures affecting renal blood flow. Inflammatory responses, oxidative stress, and apoptotic pathways significantly contribute to RIRI. This study aimed to compare the renoprotective effects of Fedratinib, a JAK2 inhibitor, and Upadacitinib, a JAK1 inhibitor, in rat models of RIRI. Both inhibitors were administered one hour prior to ischemia induction, and the effects on renal function, inflammation, and cell death pathways were assessed. The findings revealed that both Fedratinib and Upadacitinib significantly reduced serum creatinine and urea levels, inflammatory cytokines (TNF-α, IL-6), and markers of apoptosis (BCL2/BAX) by suppressing the JAK/STAT signaling pathways. Histopathological analysis showed substantial reduction in renal tissue damage in the treated groups compared to controls. The study concludes that JAK inhibition by either drug provides significant renoprotection in RIRI, though with some differences in the degree of pathway inhibition and clinical implications.

CK-666 protects against ferroptosis and renal ischemia-reperfusion injury through a microfilament-independent mechanism.

Ferroptosis is a type of regulated cell death driven by iron-dependent accumulation of lipid peroxidation, exhibiting unique morphological changes. While actin microfilaments are crucial for various cellular processes, including morphogenesis, motility, endocytosis, and cell death, their role in ferroptosis remains unclear. Here, our study reveals that actin microfilaments undergo remodeling and disassembly during ferroptosis. Interestingly, inhibitors that target actin microfilament remodeling do not affect cell sensitivity to ferroptosis, with the exception of CK-666 and its structural analogue CK-636. Mechanistically, CK-666 attenuates ferroptosis independently of its canonical function in inhibiting the Arp2/3 complex. Further investigation revealed that CK-666 modulates the ferroptotic transcriptome, prevents lipid degradation, and diminishes lipid peroxidation. In addition, CK-666 does not impact the labile iron pool within cells, nor does the inhibition of FSP1 impact its anti-ferroptosis activity. Notably, the results of DPPH assay and liposome leakage assay suggest that CK-666 mitigates ferroptosis by directly eliminating lipid peroxidation. Importantly, CK-666 significantly ameliorated renal ischemia-reperfusion injury and ferroptosis in renal tissue, underscoring its potential therapeutic impact.

The Potential Renoprotective Effect of Fedratinib in Renal Ischemia Reperfusion Injury in Male Rat Model

Renal Ischemia Reperfusion Injury (RIRI) is a serious condition that arises following kidney transplantation or other circumstances that result in decreased blood supply to the kidneys, these conditions cause a harm to the renal tissue. Gaining insight into the fundamental mechanisms of RIRI, including inflammation, cell death pathways, is essential for the development of successful therapeutic approaches. Objective: This study aimed to assess the effects of Fedratinib, a JAK2 inhibitor, in reducing RIRI in a rat model. The study involved rats divided into four groups: Sham group, control group, vehicle group, and Fedratinib group. Rats underwent anaesthesia and midline incision to expose renal pedicles, with blood flow halted using microvascular clamps. The wound was stitched, and the animals were left for 90 minutes to allow reperfusion. Blood samples were collected from the heart apex to assess serum urea and creatinine, and renal slices were used for PCR to detect the jak2/stat3 pathway. The Elisa was used to evaluate TNF, IL-6, NF-κB, Bax, Bcl2, and HMGB levels. Results: IL-6 and TNF-α, and HMGB1 were identified to have a role in the development of RIRI, inhibition of JAK2/STAT3 pathway by Fedratinib significantly decrease their concentration and minimizing RIRI. Suppression of JAK2/STAT3 pathway led to a significant inhibition in NF-κB and apoptosis. Conclusion: Fedratinib has a potential preventive effect against RIRI through their activity as JAK2 inhibitor and inhibition of the following downstream inflammatory pathways.

Potential nephroprotective effect of dapagliflozin against renal ischemia reperfusion injury in rats via activation of autophagy pathway and inhibition of inflammation, oxidative stress and apoptosis

Renal ischemia/reperfusion injury is a common cause of acute kidney injury (AKI), causing tissue damage, inflammation and oxidative stress. Autophagy, responsible for breakdown and recycling of cytoplasmic components. In hypoxic and ischemic renal damage, autophagy may serve as a survival strategy for the cells. Dapagliflozin has been shown to have protective effects against ischemia. Objective: The study investigates the potential nephro-protective effects of dapagliflozin on renal ischemia reperfusion injury, evaluating its antioxidant, anti-inflammatory, anti-apoptotic effects and activation of autophagy via biochemical parameters and histopathological changes in adult male rats. Material and method: In this study, twenty eight male rats weighing between 200-300g, were divided into 4 groups sham, RIRI, DMSO, Dapagliflozin pretreated groups. All groups subjected to 30 min. of ischemia then 24 h of reperfusion except sham undergo the same anesthesia and surgical procedures except for bilateral renal ischemia. Dapagliflozin 1mg/kg and DMSO was given 2 hours before the induction of ischemia. Results: The study found that blood urea and serum creatinine levels increased in RIRI and DMSO groups when compared with sham group. Renal tissue levels of IL-6, Kim-1, caspase-3, LC-3 and Akt were also elevated in RIRI while GSH levels decreased in the RIRI. Dapagliflozin group showed significant increases in GSH, LC-3 and Akt levels when compared to sham group. Dapagliflozin reduced serum urea and creatinine levels, and renal tissue levels of IL-6, Kim-1, and caspase-3 also reduced. Conclusion: Dapagliflozin significantly reduced renal damage in rat model due to its antioxidant, anti-inflammatory, anti-apoptotic, and activation autophagy.

Research progress on the pathogenesis of AKI complicated by ECMO.

Extracorporeal membrane oxygenation (ECMO) stands as a pivotal intervention for patients grappling with cardiopulmonary insufficiency. However, alongside its therapeutic benefits, ECMO carries the risk of complications, with acute kidney injury (AKI) emerging as a significant concern. The precise pathophysiological underpinnings of AKI in the context of ECMO remain incompletely elucidated. A comprehensive literature review was conducted to explore the epidemiology and pathophysiological mechanisms underlying the utilization of ECMO in the management of AKI. ECMO initiates a multifaceted cascade of inflammatory reactions, encompassing complement activation, endothelial dysfunction, white blood cell activation, and cytokine release. Furthermore, factors such as renal hypoperfusion, ischemia-reperfusion injury, hemolysis, and fluid overload exacerbate AKI. Specifically, veno-arterial ECMO (VA-ECMO) may directly induce renal hypoperfusion, whereas veno-venous ECMO (VV-ECMO) predominantly impacts pulmonary function, indirectly influencing renal function. While ECMO offers significant therapeutic advantages, AKI persists as a potentially fatal complication. A thorough comprehension of the pathogenesis underlying ECMO-associated AKI is imperative for effective prevention and management strategies. Moreover, additional research is warranted to delineate the incidence of AKI secondary to ECMO and to refine clinical approaches accordingly.

Liraglutide alleviates ferroptosis in renal ischemia reperfusion injury via inhibiting macrophage extracellular trap formation

Background and purposeRenal transplantation and other conditions with transiently reduced blood flow is major cause of renal ischemia/reperfusion injury (RIRI), a therapeutic challenge clinically. This study investigated the role of liraglutide in ferroptosis-associated RIRI via macrophage extracellular traps (METs). MethodsAnimal model with RIRI was established in C57BL/6J mice. A total of 72 C57BL/6J mice were used with 8 mice per group. Primary tubular epithelium was co-culture with RAW264.7 under hypoxia/reoxygenation (H/R) condition to mimic in vitro. Liraglutide was administrated into mice and cells. Extracellular DNA, neutrophil elastase and myeloperoxidase in serum and supernatant of cell medium were collected for measuring METs. F4/80 and citH3 were labeled to show METs. ResultsLiraglutide relieved RIRI and ferroptosis in vivo, and inhibited renal I/R-induced METs both in vivo and in vitro. F4/80 and citrullinated histone H3 (citH3) were highly co-localized after RIRI. Liraglutide attenuated the co-localization of citH3 and F4/80. Expressions of M2 markers were enhanced whereas these of M1 markers suppressed during liraglutide treatment in RIRI. Phosphorylation of signal transducer and activator of transcription (STAT)1, 3 and 6 were increased in RIRI mice and H/R-induced RAW264.7. However, liraglutide decreased phosphorylation of STAT1 and increased phosphorylation of STAT3 and STAT6. STAT3/6 inhibition reversed liraglutide-inhibited M1 polarization, extracellular traps and ferroptosis. ConclusionLiraglutide inhibited ferroptosis-induced renal dysfunction since it skewed macrophage polarization into M2 phenotype that interfered the formation of extracellular traps based on STAT3/6 pathway during RIRI. Liraglutide was proposed to be used for RIRI clinical treatment.

EXPRESS:Molecular Mechanisms of Ferroptosis in Renal Ischemia-Reperfusion Injury Investigated via Bioinformatics Analysis and Animal Experiments.

Kidney transplantation is a pivotal treatment for end-stage renal disease (ESKD). However, renal ischemia-reperfusion injury (IRI) during surgery significantly impacts graft function. Despite unclear molecular mechanisms, no specific therapies or preventative measures are available. Gene expression profiles from renal biopsies before and after IRI were downloaded from public databases. Differentially expressed genes (DEGs) were identified using the Wilcoxon rank-sum test and weighted gene co-expression network analysis. Ferroptosis-associated genes were screened using the FerrDb database. The genes with the highest connectivity were identified via the PPI network, and upstream regulatory miRNAs were found through the gene-miRNA network. A mouse renal IRI model was constructed for transcriptome sequencing and qRT-PCR validation to elucidate the relationship between key ferroptosis genes and regulatory miRNAs in renal IRI. Differential analysis identified 15 ferroptosis-associated genes (TNFAIP3, IL6, KLF2, EGR1, JUN, ZFP36, GDF15, CDKN1A, HSPB1, BRD2, PDK4, DUSP1, SLC2A3, DDIT3, CXCL2) involved in renal IRI regulation. In animal experiments, ferroptosis-related genes were also upregulated in the model group. Enrichment analysis and H&E pathological staining suggested these genes are primarily involved in renal inflammatory responses. PPI network analysis revealed IL6 as the gene with the highest connectivity, and the gene-miRNA network indicated IL6 might be regulated by miR-let-7a. Animal experiments revealed decreased miR-let-7a and increased IL6 levels in the model group, identifying potential therapeutic targets. MiR-let-7a regulates ferroptosis in renal IRI by targeting IL6, highlighting IL6 as a crucial gene in the ferroptosis process of renal IRI.

Silibinin attenuates ferroptosis in acute kidney injury by targeting FTH1

Acute kidney injury (AKI) is primarily caused by renal ischemia-reperfusion injury (IRI), which is one of the most prevalent triggers. Currently, preventive and therapeutic measures remain limited. Ferroptosis plays a significant role in the pathophysiological process of IRI-induced AKI and is considered a key target for improving its outcomes. Silibinin, a polyphenolic flavonoid, possesses diverse pharmacological properties and is widely used as an effective therapeutic agent for liver diseases. Recent studies have reported that silibinin may improves kidney diseases, though the underlying mechanism remain unclear. In this study, we investigated whether silibinin protects against IRI-induced AKI and explored its mechanism of action. Our findings indicated that pretreatment with silibinin alleviated renal dysfunction, pathological damage, and inflammation in IRI-AKI mice. Furthermore, the results demonstrated that silibinin inhibited ferroptosis both in vivo and in vitro. Proteome microarrays were used to identify silibinin's target, and our results revealed that silibinin binds to FTH1. This binding affinity was confirmed through molecular docking, SPRi, CETSA, and DARTS. Additionally, co-IP assays demonstrated that silibinin disrupted the NCOA4-FTH1 interaction, inhibiting ferritinophagy. Finally, the inhibitory effects of silibinin on ferroptosis were reversed by knocking down FTH1 in vitro. In conclusion, our study shows that silibinin effectively alleviates AKI by targeting FTH1 to reduce ferroptosis, suggesting that silibinin could be developed as a potential therapeutic agent for managing and treating AKI.