Tubular cell-derived exosomal miR-150-5p contributes to renal fibrosis following unilateral ischemia-reperfusion injury by activating fibroblast in vitro and in vivo

Chronic kidney disease (CKD), which is associated with high morbidity, remains a worldwide health concern, while effective therapies remain limited. Hydroxychloroquine (HCQ), which mainly targets toll-like receptor-7 (TLR-7) and TLR-9, is associated with a lower risk of incident CKD. Taking into account that TLR-9 is involved in the development of renal fibrosis and serves as a potential therapy target for CKD, we investigated whether HCQ could attenuate CKD via TLR-9 signal pathway. The effects of HCQ on renal tubulointerstitial fibrosis were further explored using a mouse model of renal tubulointerstitial fibrosis after ischemia/reperfusion injury. Bone marrow-derived macrophages were isolated to explore the effects of HCQ in vitro. Judicious use of HCQ efficiently inhibited the activation of macrophages and MAPK signaling pathways, thereby attenuating renal fibrosis in vivo. In an in vitro model, results showed that HCQ promoted apoptosis of macrophages and inhibited activation of macrophages, especially M2 macrophages, in a dose-dependent manner. Because TLR-7 is not involved in the development of CKD post-injury, a TLR-9 knockout mouse was used to explore the mechanisms of HCQ. The effects of HCQ on renal fibrosis and macrophages decreased after depletion of TLR-9 in vivo and in vitro. Taken together, this study indicated that proper use of HCQ could be a new strategy for anti-fibrotic therapy and that TLR-9 could be a potential therapeutic target for CKD following acute kidney injury.

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NMDA receptor-mediated CaMKII/ERK activation contributes to renal fibrosis

BMC Nephrology ◽

10.1186/s12882-020-02050-x ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Jingyi Zhou ◽

Shuaihui Liu ◽

Luying Guo ◽

Rending Wang ◽

Jianghua Chen ◽

...

Keyword(s):

Reperfusion Injury ◽

Renal Fibrosis ◽

Epithelial To Mesenchymal Transition ◽

Ischemia Reperfusion Injury ◽

Smooth Muscle Actin ◽

Ischemia Reperfusion ◽

Mesenchymal Transition ◽

Erk Activation

Abstract Background This study aimed to understand the mechanistic role of N-methyl-D-aspartate receptor (NMDAR) in acute fibrogenesis using models of in vivo ureter obstruction and in vitro TGF-β administration. Methods Acute renal fibrosis (RF) was induced in mice by unilateral ureteral obstruction (UUO). Histological changes were observed using Masson’s trichrome staining. The expression levels of NR1, which is the functional subunit of NMDAR, and fibrotic and epithelial-to-mesenchymal transition markers were measured by immunohistochemical and Western blot analysis. HK-2 cells were incubated with TGF-β, and NMDAR antagonist MK-801 and Ca2+/calmodulin-dependent protein kinase II (CaMKII) antagonist KN-93 were administered for pathway determination. Chronic RF was introduced by sublethal ischemia–reperfusion injury in mice, and NMDAR inhibitor dextromethorphan hydrobromide (DXM) was administered orally. Results The expression of NR1 was upregulated in obstructed kidneys, while NR1 knockdown significantly reduced both interstitial volume expansion and the changes in the expression of α-smooth muscle actin, S100A4, fibronectin, COL1A1, Snail, and E-cadherin in acute RF. TGF-β1 treatment increased the elongation phenotype of HK-2 cells and the expression of membrane-located NR1 and phosphorylated CaMKII and extracellular signal–regulated kinase (ERK). MK801 and KN93 reduced CaMKII and ERK phosphorylation levels, while MK801, but not KN93, reduced the membrane NR1 signal. The levels of phosphorylated CaMKII and ERK also increased in kidneys with obstruction but were decreased by NR1 knockdown. The 4-week administration of DXM preserved renal cortex volume in kidneys with moderate ischemic–reperfusion injury. Conclusions NMDAR participates in both acute and chronic renal fibrogenesis potentially via CaMKII-induced ERK activation.

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N6-methyladenosine demethylase FTO impairs hepatic ischemia–reperfusion injury via inhibiting Drp1-mediated mitochondrial fragmentation

Cell Death and Disease ◽

10.1038/s41419-021-03622-x ◽

2021 ◽

Vol 12 (5) ◽

Author(s):

Ying Dong Du ◽

Wen Yuan Guo ◽

Cong Hui Han ◽

Ying Wang ◽

Xiao Song Chen ◽

...

Keyword(s):

Reperfusion Injury ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Mitochondrial Fragmentation ◽

Hepatic Ischemia ◽

Adeno Associated Virus ◽

Downstream Target ◽

Hepatic Ischemia Reperfusion

AbstractDespite N6-methyladenosine (m6A) is functionally important in various biological processes, its role and the underlying regulatory mechanism in the liver remain largely unexplored. In the present study, we showed that fat mass and obesity-associated protein (FTO, an m6A demethylase) was involved in mitochondrial function during hepatic ischemia–reperfusion injury (HIRI). We found that the expression of m6A demethylase FTO was decreased during HIRI. In contrast, the level of m6A methylated RNA was enhanced. Adeno-associated virus-mediated liver-specific overexpression of FTO (AAV8-TBG-FTO) ameliorated the HIRI, repressed the elevated level of m6A methylated RNA, and alleviated liver oxidative stress and mitochondrial fragmentation in vivo and in vitro. Moreover, dynamin-related protein 1 (Drp1) was a downstream target of FTO in the progression of HIRI. FTO contributed to the hepatic protective effect via demethylating the mRNA of Drp1 and impairing the Drp1-mediated mitochondrial fragmentation. Collectively, our findings demonstrated the functional importance of FTO-dependent hepatic m6A methylation during HIRI and provided valuable insights into the therapeutic mechanisms of FTO.

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In vivo and In vitro PPAR-y Activation Decreases M1-Macrophage Polarization and Improves Liver Ischemia Reperfusion Injury

Transplantation Journal ◽

10.1097/01.tp.0000543674.85457.9b ◽

2018 ◽

Vol 102 ◽

pp. S708

Author(s):

Ivan Linares ◽

Agata Bartczak ◽

Kaveh Farrokhi ◽

Dagmar Kollmann ◽

Moritz Kaths ◽

...

Keyword(s):

Reperfusion Injury ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Macrophage Polarization ◽

Liver Ischemia ◽

M1 Macrophage

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Poly-IC Preconditioning Protects against Cerebral and Renal Ischemia-Reperfusion Injury

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2011.160 ◽

2011 ◽

Vol 32 (2) ◽

pp. 242-247 ◽

Cited By ~ 29

Author(s):

Amy E B Packard ◽

Jason C Hedges ◽

Frances R Bahjat ◽

Susan L Stevens ◽

Michael J Conlin ◽

...

Keyword(s):

Reperfusion Injury ◽

Inflammatory Responses ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Renal Ischemia ◽

Cortical Cells ◽

Polycytidylic Acid ◽

Populations At Risk

Preconditioning induces ischemic tolerance, which confers robust protection against ischemic damage. We show marked protection with polyinosinic polycytidylic acid (poly-IC) preconditioning in three models of murine ischemia-reperfusion injury. Poly-IC preconditioning induced protection against ischemia modeled in vitro in brain cortical cells and in vivo in models of brain ischemia and renal ischemia. Further, unlike other Toll-like receptor (TLR) ligands, which generally induce significant inflammatory responses, poly-IC elicits only modest systemic inflammation. Results show that poly-IC is a new powerful prophylactic treatment that offers promise as a clinical therapeutic strategy to minimize damage in patient populations at risk of ischemic injury.

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Transplantation-Induced Ischemia-Reperfusion Injury Modulates Antigen Presentation by Donor Renal CD11c+F4/80+ Macrophages through IL-1R8 Regulation

Journal of the American Society of Nephrology ◽

10.1681/asn.2019080778 ◽

2020 ◽

Vol 31 (3) ◽

pp. 517-531 ◽

Cited By ~ 1

Author(s):

Sistiana Aiello ◽

Manuel Alfredo Podestà ◽

Pamela Y. Rodriguez-Ordonez ◽

Francesca Pezzuto ◽

Nadia Azzollini ◽

...

Keyword(s):

Reperfusion Injury ◽

Antigen Presentation ◽

Kidney Transplant ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Cold Ischemia ◽

Reversible Ischemia ◽

Antigen Presenting

BackgroundIn donor kidneys subjected to ischemia-reperfusion injury during kidney transplant, phagocytes coexpressing the F4/80 and CD11c molecules mediate proinflammatory responses and trigger adaptive immunity in transplantation through antigen presentation. After injury, however, resident renal macrophages coexpressing these surface markers acquire a proreparative phenotype, which is pivotal in controlling inflammation and fibrosis. No data are currently available regarding the effects of transplant-induced ischemia-reperfusion injury on the ability of donor-derived resident renal macrophages to act as professional antigen-presenting cells.MethodsWe evaluated the phenotype and function of intragraft CD11c+F4/80+ renal macrophages after cold ischemia. We also assessed the modifications of donor renal macrophages after reversible ischemia-reperfusion injury in a mouse model of congeneic renal transplantation. To investigate the role played by IL-1R8, we conducted in vitro and in vivo studies comparing cells and grafts from wild-type and IL-R8–deficient donors.ResultsCold ischemia and reversible ischemia-reperfusion injury dampened antigen presentation by renal macrophages, skewed their polarization toward the M2 phenotype, and increased surface expression of IL-1R8, diminishing activation mediated by toll-like receptor 4. Ischemic IL-1R8–deficient donor renal macrophages acquired an M1 phenotype, effectively induced IFNγ and IL-17 responses, and failed to orchestrate tissue repair, resulting in severe graft fibrosis and aberrant humoral immune responses.ConclusionsIL-1R8 is a key regulator of donor renal macrophage functions after ischemia-reperfusion injury, crucial to guiding the phenotype and antigen-presenting role of these cells. It may therefore represent an intriguing pathway to explore with respect to modulating responses against autoantigens and alloantigens after kidney transplant.

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In vitro analysed effects of two different in vivo administered lidocaine dosageson the equine jejunal smooth muscle challenged by an ischemia-reperfusion-injury-model (IRIM)

Pferdeheilkunde Equine Medicine ◽

10.21836/pem20120507 ◽

2012 ◽

Vol 28 (5) ◽

pp. 570-574

Author(s):

F Uhlendorf ◽

M Guschlbauer ◽

S Hoppe ◽

K Huber ◽

K Feige

Keyword(s):

Smooth Muscle ◽

Reperfusion Injury ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Injury Model

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P0516DCR2 PROMOTES RENAL FIBROSIS BY ACCELERATING TUBULAR CELL SENESCENCE AFTER ISCHEMIA REPERFUSION INJURY

Nephrology Dialysis Transplantation ◽

10.1093/ndt/gfaa143.p0516 ◽

2020 ◽

Vol 35 (Supplement_3) ◽

Author(s):

Jia Chen ◽

Yani He

Keyword(s):

Reperfusion Injury ◽

Renal Injury ◽

Renal Fibrosis ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Cell Senescence ◽

Tubular Cell ◽

Renal Tubules ◽

Senescent Phenotype ◽

Renal Tubular

Abstract Background and Aims Cell senescence of renal tubular epithelial cells (RTECs), which is involved in renal fibrosis, is a key event in the progression of acute kidney injury (AKI). However, the underlying mechanism remains unclear. This study aims to investigate the role and mechanism of decoy receptor 2 (DcR2) in renal fibrosis and cell senescence of RTECs. Method KSP-creDcR2f/f mouse (Tubular DcR2 KO) and Ischemia-Reperfusion (I/R) Injury models were constructed. The models were divided into moderated (ischemia 20min) and severe (ischemia 35min) injury. The expression of renal DcR2, senescent markers (P16, P21, SA-β-gal) and senescent phenotype (IL-6, TGF-β1) were detected. Furthermore, wild type (WT) mice and KSP-creDcR2f/f mice were used to compare the degree of renal tissue and functional damage and the senescence of renal tubular cells after I/R injury. In vitro, knockdown and overexpression experiments were performed by transfected DcR2 siRNA or overexpressed adenovirus in hypoxia-reoxygenation stimulated mouse primary RTEC. The cell senescence and phenotype markers were further detected. Results The levels of Scr, BUN and urinary DcR2 and renal injury scores were significantly increased in I/R group at the early stage (1d) of renal injury compared with sham group. Renal fibrosis was observed in the later stage (21-42d) in severe injury. DcR2 was mainly expressed in renal tubules, and the percentage of tubular DcR2 was increased after I/R injury. DcR2 was co-expressed with P16 and SA-β-gal, and urinary DcR2 levels were related to senescent makers, suggesting that DcR2 was associated with cell senescence. The renal function and renal injury scores were lower in KSP-creDcR2f/f mice than that of WT after renal reperfusion. And the area of renal fibrosis was significantly decreased in KSP-creDcR2f/f mice compared with WT, indicating DcR2 inhibited renal fibrosis. Furthermore, the expression of senescent phenotype were suppressed in tubular DcR2 KO mice after I/R injury, suggesting that DcR2 could promote the senescence of renal tubule cells. Conclusion DcR2 promotes renal fibrosis by accelerating tubular cell senescence after ischemia-reperfusion Injury, suggesting that DcR2 may be a potential intervention target during the progression of AKI.

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Inhibition of BRD4 Reduces Neutrophil Activation and Adhesion to the Vascular Endothelium Following Ischemia Reperfusion Injury

International Journal of Molecular Sciences ◽

10.3390/ijms21249620 ◽

2020 ◽

Vol 21 (24) ◽

pp. 9620

Author(s):

Shelby Reid ◽

Noah Fine ◽

Vikrant K. Bhosle ◽

Joyce Zhou ◽

Rohan John ◽

...

Keyword(s):

Endothelial Cells ◽

Reperfusion Injury ◽

Ischemia Reperfusion Injury ◽

Ischemia Reperfusion ◽

Neutrophil Adhesion ◽

Neutrophil Accumulation ◽

Iri Model ◽

Brd4 Inhibition

Renal ischemia reperfusion injury (IRI) is associated with inflammation, including neutrophil infiltration that exacerbates the initial ischemic insult. The molecular pathways involved are poorly characterized and there is currently no treatment. We performed an in silico analysis demonstrating changes in NFκB-mediated gene expression in early renal IRI. We then evaluated NFκB-blockade with a BRD4 inhibitor on neutrophil adhesion to endothelial cells in vitro, and tested BRD4 inhibition in an in vivo IRI model. BRD4 inhibition attenuated neutrophil adhesion to activated endothelial cells. In vivo, IRI led to increased expression of cytokines and adhesion molecules at 6 h post-IRI with sustained up-regulated expression to 48 h post-IRI. These effects were attenuated, in part, with BRD4 inhibition. Absolute neutrophil counts increased significantly in the bone marrow, blood, and kidney 24 h post-IRI. Activated neutrophils increased in the blood and kidney at 6 h post-IRI and remained elevated in the kidney until 48 h post-IRI. BRD4 inhibition reduced both total and activated neutrophil counts in the kidney. IRI-induced tubular injury correlated with neutrophil accumulation and was reduced by BRD4 inhibition. In summary, BRD4 inhibition has important systemic and renal effects on neutrophils, and these effects are associated with reduced renal injury.

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