Exocyst Sec10 protects renal tubule cells from injury by EGFR/MAPK activation and effects on endocytosis

Acute kidney injury is common and has a high mortality rate, and no effective treatment exists other than supportive care. Using cell culture models, we previously demonstrated that exocyst Sec10 overexpression reduced damage to renal tubule cells and speeded recovery and that the protective effect was mediated by higher basal levels of mitogen-activated protein kinase (MAPK) signaling. The exocyst, a highly-conserved eight-protein complex, is known for regulating protein trafficking. Here we show that the exocyst biochemically interacts with the epidermal growth factor receptor (EGFR), which is upstream of MAPK, and Sec10-overexpressing cells express greater levels of phosphorylated (active) ERK, the final step in the MAPK pathway, in response to EGF stimulation. EGFR endocytosis, which has been linked to activation of the MAPK pathway, increases in Sec10-overexpressing cells, and gefitinib, a specific EGFR inhibitor, and Dynasore, a dynamin inhibitor, both reduce EGFR endocytosis. In turn, inhibition of the MAPK pathway reduces ligand-mediated EGFR endocytosis, suggesting a potential feedback of elevated ERK activity on EGFR endocytosis. Gefitinib also decreases MAPK signaling in Sec10-overexpressing cells to levels seen in control cells and, demonstrating a causal role for EGFR, reverses the protective effect of Sec10 overexpression following cell injury in vitro. Finally, using an in vivo zebrafish model of acute kidney injury, morpholino-induced knockdown of sec10 increases renal tubule cell susceptibility to injury. Taken together, these results suggest that the exocyst, acting through EGFR, endocytosis, and the MAPK pathway is a candidate therapeutic target for acute kidney injury.

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Protective Effects of Traditional Polyherbs on Cisplatin-Induced Acute Kidney Injury Cell Model by Inhibiting Oxidative Stress and MAPK Signaling Pathway

Molecules ◽

10.3390/molecules25235641 ◽

2020 ◽

Vol 25 (23) ◽

pp. 5641

Author(s):

VinayKumar Dachuri ◽

Phil Hyun Song ◽

Young Woo Kim ◽

Sae-Kwang Ku ◽

Chang-Hyun Song

Keyword(s):

Acute Kidney Injury ◽

Cell Injury ◽

Cell Model ◽

Alternative Therapy ◽

Radical Scavenging ◽

Kidney Injury ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Renal Diseases ◽

Protective Effects

Acute kidney injury (AKI) is a disease caused by sudden renal dysfunction, which is an important risk factor for chronic renal failure. However, there is no effective treatment for renal impairment. Although some traditional polyherbs are commercially available for renal diseases, their effectiveness has not been reported. Therefore, we examined the nephroprotective effects of polyherbs and their relevant mechanisms in a cisplatin-induced cell injury model. Rat NRK-52E and human HK-2 subjected to cisplatin-induced AKI were treated with four polyherbs, Injinhotang (IJ), Ucha-Shinki-Hwan (US), Yukmijihwang-tang (YJ), and UrofenTM (Uro) similar with Yondansagan-tang, for three days. All polyherbs showed strong free radical scavenging activities, and the treatments prevented cisplatin-induced cell death in both models, especially at 1.2 mg/mL. The protective effects involved antioxidant effects by reducing reactive oxygen species and increasing the activities of superoxide dismutase and catalase. The polyherbs also reduced the number of annexin V-positive apoptotic cells and the expression of cleaved caspase-3, along with inhibited expression of mitogen-activated protein kinase-related proteins. These findings provide evidence for promoting the development of herbal formulas as an alternative therapy for treating AKI.

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Platycodin D Ameliorates Acute Kidney Injury in Septic Rats by Regulating Mitogen Activated Protein Kinase Pathway

Current Topics in Nutraceutical Research ◽

10.37290/ctnr2641-452x.19:270-276 ◽

2020 ◽

Vol 19 (3) ◽

pp. 270-276

Author(s):

Jianying Wang ◽

Xiaoting Yu

Keyword(s):

Acute Kidney Injury ◽

Protein Kinase ◽

Protective Effect ◽

Cecal Ligation ◽

Kidney Injury ◽

B Cell Lymphoma ◽

Mitogen Activated Protein Kinase ◽

Cecal Ligation And Puncture ◽

Platycodin D ◽

Mitogen Activated Protein

Acute kidney injury is a severe complication of sepsis. We have shown a protective effect of Platycodin D on sepsis induced acute kidney injury in an animal model that employs cecal ligation and puncture. Cecal ligation and puncture induced a series of degenerative changes in kidney, such as edema, hyperemia, and expansion in glomerular capillary, and inflammatory cells infiltration that were attenuated by Platycodin D. Also, rise in proinflammatory cytokine levels in septic rats was blunted by Platycodin D. Furthermore, Platycodin D administration reduced rise in serum levels of kidney injury markers-blood urea nitrogen and serum creatinine-in septic rats. Moreover, Platycodin D administration also suppressed the cell apoptosis in kidney that was associated with enhanced B-cell lymphoma 2 protein and reduced cleaved cysteine-aspartic protease-3 and BCL2-associated X protein. Lastly, Platycodin D administration attenuated sepsis-induced increase of phospho (p)-extracellular signal-regulated kinase, p-c-Jun NH2-terminal kinase, and p-p38. In conclusion, Platycodin D demonstrated protective effect against sepsis induced acute kidney injury through inactivation of mitogen activated protein kinase pathways, thus providing promising therapeutic strategy for the treatment of sepsis.

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Ibudilast Attenuates Folic Acid–Induced Acute Kidney Injury by Blocking Pyroptosis Through TLR4-Mediated NF-κB and MAPK Signaling Pathways

Frontiers in Pharmacology ◽

10.3389/fphar.2021.650283 ◽

2021 ◽

Vol 12 ◽

Author(s):

Xue Li ◽

Yu Zou ◽

Yuan-Yuan Fu ◽

Jia Xing ◽

Kai-Yue Wang ◽

...

Keyword(s):

Acute Kidney Injury ◽

Folic Acid ◽

Protective Effect ◽

Signaling Pathways ◽

Nuclear Translocation ◽

Kidney Injury ◽

Mapk Signaling ◽

Inflammatory Factor ◽

Anti Inflammatory ◽

Mapk Signaling Pathways

Folic acid (FA)-induced renal tubule damage, which is characterized by extensive inflammation, is a common model of acute kidney injury (AKI). Pyroptosis, a pro-inflammatory form of cell death due to the activation of inflammatory caspases, is involved in AKI progression. Ibudilast, a TLR4 antagonist, has been used in the clinic to exert an anti-inflammatory effect on asthma. However, researchers have not explored whether ibudilast exerts a protective effect on AKI by inhibiting inflammation. In the present study, ibudilast reversed FA-induced AKI in mice, as indicated by the reduced serum creatinine and urea nitrogen levels, and improved renal pathology, as well as the downregulation of kidney injury marker-1. In addition, ibudilast significantly increased the production of the anti-inflammatory factor IL-10 while suppressing the secretion of the pro-inflammatory cytokine TNF-α and macrophage infiltration. Moreover, in the injured kidney, ibudilast reduced the levels of both inflammasome markers (NLRP3) and pyroptosis-related proteins (caspase-1, IL1-β, IL-18, and GSDMD cleavage), and decreased the number of TUNEL-positive cells. Further mechanistic studies showed that ibudilast administration inhibited the FA-induced upregulation of TLR4, blocked NF-κB nuclear translocation, and reduced the phosphorylation of NF-κB and IκBα, p38, ERK, and JNK. Thus, this study substantiates the protective effect of ibudilast on FA-induced AKI in mice and suggests that protection might be achieved by reducing pyroptosis and inflammation, likely through the inhibition of TLR4-mediated NF-κB and MAPK signaling pathways.

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SIRT1 attenuates sepsis-induced acute kidney injury via Beclin1 deacetylation-mediated autophagy activation

Cell Death and Disease ◽

10.1038/s41419-021-03508-y ◽

2021 ◽

Vol 12 (2) ◽

Author(s):

Zhiya Deng ◽

Maomao Sun ◽

Jie Wu ◽

Haihong Fang ◽

Shumin Cai ◽

...

Keyword(s):

Acute Kidney Injury ◽

Protective Effect ◽

Cell Model ◽

Kidney Injury ◽

Underlying Mechanism ◽

Autophagy Induction ◽

Promising Therapeutic Approach ◽

Related Proteins ◽

Caecal Ligation And Puncture

AbstractOur previous studies showed that silent mating-type information regulation 2 homologue-1 (SIRT1, a deacetylase) upregulation could attenuate sepsis-induced acute kidney injury (SAKI). Upregulated SIRT1 can deacetylate certain autophagy-related proteins (Beclin1, Atg5, Atg7 and LC3) in vitro. However, it remains unclear whether the beneficial effect of SIRT1 is related to autophagy induction and the underlying mechanism of this effect is also unknown. In the present study, caecal ligation and puncture (CLP)-induced mice, and an LPS-challenged HK-2 cell line were established to mimic a SAKI animal model and a SAKI cell model, respectively. Our results demonstrated that SIRT1 activation promoted autophagy and attenuated SAKI. SIRT1 deacetylated only Beclin1 but not the other autophagy-related proteins in SAKI. SIRT1-induced autophagy and its protective effect against SAKI were mediated by the deacetylation of Beclin1 at K430 and K437. Moreover, two SIRT1 activators, resveratrol and polydatin, attenuated SAKI in CLP-induced septic mice. Our study was the first to demonstrate the important role of SIRT1-induced Beclin1 deacetylation in autophagy and its protective effect against SAKI. These findings suggest that pharmacologic induction of autophagy via SIRT1-mediated Beclin1 deacetylation may be a promising therapeutic approach for future SAKI treatment.

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NEAT1 aggravates sepsis-induced acute kidney injury by sponging miR-22-3p

Open Medicine ◽

10.1515/med-2020-0401 ◽

2020 ◽

Vol 15 (1) ◽

pp. 333-342

Author(s):

Yawei Feng ◽

Jun Liu ◽

Ranliang Wu ◽

Peng Yang ◽

Zhiqiang Ye ◽

...

Keyword(s):

Acute Kidney Injury ◽

Western Blot ◽

Cell Apoptosis ◽

Noncoding Rna ◽

Cell Injury ◽

Kidney Injury ◽

Inflammatory Factors ◽

Luciferase Reporter ◽

Enzyme Linked Immunosorbent Assay ◽

Western Blot Assay

AbstractBackground and aimAcute kidney injury (AKI) is a common complication of sepsis. Long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) plays a vital role in various diseases, including AKI. This study aimed to investigate the function and mechanism of NEAT1 in sepsis-induced AKI.Materials and methodsA septic AKI model was established by treating HK-2 cells with lipopolysaccharide (LPS). The levels of NEAT1 and miR-22-3p were measured by quantitative real-time PCR. Cell apoptosis was assessed by flow cytometry. The levels of apoptosis-related protein and autophagy-related factors were examined by the western blot assay. An enzyme-linked immunosorbent assay was used to calculate the contents of inflammatory factors. The interaction between NEAT1 and miR-22-3p was validated by dual-luciferase reporter assay, RNA immunoprecipitation assay, and RNA pull-down assay. The levels of nuclear factor (NF)-κB pathway-related proteins were evaluated by the western blot assay.ResultsNEAT1 was upregulated, while miR-22-3p was downregulated in patients with sepsis and in LPS-stimulated HK-2 cells. LPS treatment triggered cell apoptosis, autophagy, and inflammatory response in HK-2 cells. NEAT1 knockdown attenuated LPS-induced cell injury. NEAT1 modulated LPS-triggered cell injury by targeting miR-22-3p. Furthermore, NEAT1 regulated the NF-κB pathway by modulating miR-22-3p.ConclusionDepletion of NEAT1 alleviated sepsis-induced AKI via regulating the miR-22-3p/NF-κB pathway.

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DNA demethylase Tet2 suppresses cisplatin-induced acute kidney injury

Cell Death Discovery ◽

10.1038/s41420-021-00528-7 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Yinwu Bao ◽

Mengqiu Bai ◽

Huanhuan Zhu ◽

Yuan Yuan ◽

Ying Wang ◽

...

Keyword(s):

Acute Kidney Injury ◽

Signaling Pathway ◽

Cell Injury ◽

Inflammatory Responses ◽

Kidney Injury ◽

Renal Tissue ◽

Clinical Samples ◽

Mice Model ◽

Expression Levels ◽

Ppar Signaling

AbstractDemethylase Tet2 plays a vital role in the immune response. Acute kidney injury (AKI) initiation and maintenance phases are marked by inflammatory responses and leukocyte recruitment in endothelial and tubular cell injury processes. However, the role of Tet2 in AKI is poorly defined. Our study determined the degree of renal tissue damage associated with Tet2 gene expression levels in a cisplatin-induced AKI mice model. Tet2-knockout (KO) mice with cisplatin treatment experienced severe tubular necrosis and dilatation, inflammation, and AKI markers’ expression levels than the wild-type mice. In addition, the administration of Tet2 plasmid protected Tet2-KO mice from cisplatin-induced nephrotoxicity, but not Tet2-catalytic-dead mutant. Tet2 KO was associated with a change in metabolic pathways like retinol, arachidonic acid, linolenic acid metabolism, and PPAR signaling pathway in the cisplatin-induced mice model. Tet2 expression is also downregulated in other AKI mice models and clinical samples. Thus, our results indicate that Tet2 has a renal protective effect during AKI by regulating metabolic and inflammatory responses through the PPAR signaling pathway.

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A zebrafish model of infection-associated acute kidney injury

AJP Renal Physiology ◽

10.1152/ajprenal.00328.2017 ◽

2018 ◽

Vol 315 (2) ◽

pp. F291-F299 ◽

Cited By ~ 7

Author(s):

Xiaoyan Wen ◽

Liyan Cui ◽

Seth Morrisroe ◽

Donald Maberry ◽

David Emlet ◽

...

Keyword(s):

Acute Kidney Injury ◽

Unmet Need ◽

Kidney Injury ◽

Edwardsiella Tarda ◽

Adult Zebrafish ◽

Zebrafish Model ◽

Pericardial Edema ◽

Kidney Injury Molecule 1 ◽

Dose Dependent

Sepsis-associated acute kidney injury (S-AKI) independently predicts mortality among critically ill patients. The role of innate immunity in this process is unclear, and there is an unmet need for S-AKI models to delineate the pathophysiological response. Mammals and zebrafish ( Danio rerio) share a conserved nephron structure and homologous innate immune systems, making the latter suitable for S-AKI research. We introduced Edwardsiella tarda to the zebrafish. Systemic E. tarda bacteremia resulted in sustained bacterial infection and dose-dependent mortality. A systemic immune reaction was characterized by increased mRNA expressions of il1b, tnfa, tgfb1a, and cxcl8-l1 ( P < 0.0001, P < 0.001, P < 0.001, and P < 0.01, respectively). Increase of host stress response genes ccnd1 and tp53 was observed at 24 h postinjection ( P < 0.0001 and P < 0.05, respectively). Moderate E. tarda infection induced zebrafish mortality of over 50% in larvae and 20% in adults, accompanied by pericardial edema in larvae and renal dysfunction in both larval and adult zebrafish. Expression of AKI markers insulin-like growth factor-binding protein-7 (IGFBP7), tissue inhibitor of metalloproteinases 2 (TIMP-2), and kidney injury molecule-1 (KIM-1) was found to be significantly increased in the septic animals at the transcription level ( P < 0.01, P < 0.05, and P < 0.05) and in nephric tubules compared with noninfected animals. In conclusion, we established a zebrafish model of S-AKI induced by E. tarda injection, with both larval and adult zebrafish showing nephron injury in the setting of infection.

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Protective Effect of Taurine on Mice with Doxorubicin-induced Acute Kidney Injury

Advances in Experimental Medicine and Biology - Taurine 10 ◽

10.1007/978-94-024-1079-2_95 ◽

2017 ◽

pp. 1191-1201 ◽

Cited By ~ 7

Author(s):

Yon-Suk Kim ◽

Si-Heung Sung ◽

Yujiao Tang ◽

Eun-Ju Choi ◽

Young-Jin Choi ◽

...

Keyword(s):

Acute Kidney Injury ◽

Protective Effect ◽

Kidney Injury

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Insulin-like growth factor binding protein 7 and tissue inhibitor of metalloproteinases-2: differential expression and secretion in human kidney tubule cells

AJP Renal Physiology ◽

10.1152/ajprenal.00271.2016 ◽

2017 ◽

Vol 312 (2) ◽

pp. F284-F296 ◽

Cited By ~ 38

Author(s):

David R. Emlet ◽

Nuria Pastor-Soler ◽

Allison Marciszyn ◽

Xiaoyan Wen ◽

Hernando Gomez ◽

...

Keyword(s):

Cell Culture ◽

Acute Kidney Injury ◽

Kidney Injury ◽

Human Kidney ◽

Distal Tubule ◽

Cell Types ◽

Tissue Inhibitor Of Metalloproteinases ◽

Tubule Cell ◽

Tubule Cells

We have characterized the expression and secretion of the acute kidney injury (AKI) biomarkers insulin-like growth factor binding protein 7 (IGFBP7) and tissue inhibitor of metalloproteinases-2 (TIMP-2) in human kidney epithelial cells in primary cell culture and tissue. We established cell culture model systems of primary kidney cells of proximal and distal tubule origin and observed that both proteins are indeed expressed and secreted in both tubule cell types in vitro. However, TIMP-2 is both expressed and secreted preferentially by cells of distal tubule origin, while IGFBP7 is equally expressed across tubule cell types yet preferentially secreted by cells of proximal tubule origin. In human kidney tissue, strong staining of IGFBP7 was seen in the luminal brush-border region of a subset of proximal tubule cells, and TIMP-2 stained intracellularly in distal tubules. Additionally, while some tubular colocalization of both biomarkers was identified with the injury markers kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin, both biomarkers could also be seen alone, suggesting the possibility for differential mechanistic and/or temporal profiles of regulation of these early AKI biomarkers from known markers of injury. Last, an in vitro model of ischemia-reperfusion demonstrated enhancement of secretion of both markers early after reperfusion. This work provides a rationale for further investigation of these markers for their potential role in the pathogenesis of acute kidney injury.

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APPL1 mediates adiponectin-stimulated p38 MAPK activation by scaffolding the TAK1-MKK3-p38 MAPK pathway

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00427.2010 ◽

2011 ◽

Vol 300 (1) ◽

pp. E103-E110 ◽

Cited By ~ 59

Author(s):

Xiaoban Xin ◽

Lijun Zhou ◽

Caleb M. Reyes ◽

Feng Liu ◽

Lily Q. Dong

Keyword(s):

Protein Kinase ◽

P38 Mapk ◽

Mapk Pathway ◽

Adaptor Protein ◽

Mapk Signaling ◽

Mitogen Activated Protein Kinase ◽

Scaffolding Protein ◽

Mapk Activation ◽

P38 Mapk Pathway ◽

Mitogen Activated Protein

The adaptor protein APPL1 mediates the stimulatory effect of adiponectin on p38 mitogen-activated protein kinase (MAPK) signaling, yet the underlying mechanism remains unclear. Here we show that, in C2C12 cells, overexpression or suppression of APPL1 enhanced or suppressed, respectively, adiponectin-stimulated p38 MAPK upstream kinase cascade, consisting of transforming growth factor-β-activated kinase 1 (TAK1) and mitogen-activated protein kinase kinase 3 (MKK3). In vitro affinity binding and coimmunoprecipitation experiments revealed that TAK1 and MKK3 bind to different regions of APPL1, suggesting that APPL1 functions as a scaffolding protein to facilitate adiponectin-stimulated p38 MAPK activation. Interestingly, suppressing APPL1 had no effect on TNFα-stimulated p38 MAPK phosphorylation in C2C12 myotubes, indicating that the stimulatory effect of APPL1 on p38 MAPK activation is selective. Taken together, our study demonstrated that the TAK1-MKK3 cascade mediates adiponectin signaling and uncovers a scaffolding role of APPL1 in regulating the TAK1-MKK3-p38 MAPK pathway, specifically in response to adiponectin stimulation.

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