scholarly journals Islet Transplantation Reverses Podocyte Injury in Diabetic Nephropathy or Induced by High Glucose via Inhibiting RhoA/ROCK/NF-κB Signaling Pathway

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Chongchu Huang ◽  
Yi Zhou ◽  
Hongjian Huang ◽  
Yushu Zheng ◽  
Lijun Kong ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
Signaling Pathways ◽  
Signaling Pathway ◽  
Islet Transplantation ◽  
High Glucose ◽  
Islet Cells ◽  
Inflammatory Factors ◽  
Efficacy Evaluation ◽  
Podocyte Injury ◽  
Expression Levels

Objective. Abnormal signaling pathways play a crucial role in the mechanisms of podocyte injury in diabetic nephropathy. They also affect the recovery of podocytes after islet transplantation (IT). However, the specific signaling abnormalities that affect the therapeutic effect of IT on podocytes remains unclear. The purpose of this study was to assess whether the RhoA/ROCK/NF-κB signaling pathway is related to podocyte restoration after IT. Methods. A mouse model of diabetic nephropathy was established in vivo using streptozotocin. The mice were then subsequently reared for 4 weeks after islet transplantation to determine the effect of IT. Islet cells, CCG-1423 (RhoA Inhibitor), and fasudil (ROCK inhibitor) were then cocultured with podocytes in vitro to assess their protective effects on podocyte injury induced by high glucose (HG). Protein expression levels of RhoA, ROCK1, synaptopodin, IL-6, and MCP-1 in kidney tissues were then measured using immunohistochemistry and Western blotting techniques. Results. Islet transplantation reduced the expression levels of RhoA/ROCK1 and that of related inflammatory factors such as IL-6 and MCP-1 in the kidney podocytes of diabetic nephropathy. In the same line, islet cells reduced the expression of RhoA, ROCK1, and pp65 in immortalized podocytes under high glucose (35.0 mmol/L glucose) conditions. Conclusions. Islet transplantation can reverse podocyte injury in diabetes nephropathy by inhibiting the RhoA/ROCK1 signaling pathway. Islet cells have a strong protective effect on podocytes treated with high glucose (35.0 mmol/L glucose). Discovery of signaling pathways affecting podocyte recovery is helpful for individualized efficacy evaluation and targeted therapy of islet transplantation patients.

scholarly journals The OsOXO2, OsOXO3 and OsOXO4 Positively Regulate Panicle Blast Resistance in Rice

Rice ◽  
2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Jingfang Dong ◽  
Lian Zhou ◽  
Aiqing Feng ◽  
Shaohong Zhang ◽  
Hua Fu ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Signaling Pathway ◽  
Molecular Mechanisms ◽  
Blast Resistance ◽  
Aba Signaling ◽  
Leaf Blast ◽  
Expression Levels ◽  
Panicle Blast ◽  
Localization Analysis ◽  
Sa Signaling

Abstract Background Although panicle blast is more destructive to yield loss than leaf blast in rice, the cloned genes that function in panicle blast resistance are still very limited and the molecular mechanisms underlying panicle blast resistance remain largely unknown. Results In the present study, we have confirmed that the three Oxalate oxidase (OXO) genes, OsOXO2, OsOXO3 and OsOXO4 from a blast-resistant cultivar BC10 function in panicle blast resistance in rice. The expression of OsOXO2, OsOXO3 and OsOXO4 were induced by panicle blast inoculation. Subcellular localization analysis revealed that the three OXO proteins are all localized in the nucleus and cytoplasm. Simultaneous silencing of OsOXO2, OsOXO3 and OsOXO4 decreased rice resistance to panicle blast, whereas the OsOXO2, OsOXO3 and OsOXO4 overexpression rice plants individually showed enhanced panicle blast resistance. More H2O2 and higher expression levels of PR genes were observed in the overexpressing plants than in the control plants, while the silencing plants exhibited less H2O2 and lower expression levels of PR genes compared to the control plants. Moreover, phytohormone treatment and the phytohormone signaling related gene expression analysis showed that panicle blast resistance mediated by the three OXO genes was associated with the activation of JA and ABA signaling pathways but suppression of SA signaling pathway. Conclusion OsOXO2, OsOXO3 and OsOXO4 positively regulate panicle blast resistance in rice. The OXO genes could modulate the accumulation of H2O2 and expression levels of PR gene in plants. Moreover, the OXO genes mediated panicle blast resistance could be regulated by ABA, SA and JA, and may be associated with the activation of JA and ABA signaling pathways but suppression of the SA signaling pathway.

scholarly journals (Pro)renin receptor regulates autophagy and apoptosis in podocytes exposed to high glucose

2015 ◽  
Vol 309 (3) ◽  
pp. E302-E310 ◽  
Author(s):  
Caixia Li ◽  
Helmy M. Siragy
Keyword(s):  
Signaling Pathway ◽  
High Glucose ◽  
Caspase 3 ◽  
Mtor Signaling ◽  
Autophagic Flux ◽  
Bafilomycin A1 ◽  
Mtor Signaling Pathway ◽  
Autophagosome Formation ◽  
Podocyte Injury ◽  
Protein Levels

High glucose reduces autophagy and enhances apoptosis of podocytes. Previously, we reported that high glucose induced podocyte injury through upregulation of the (pro)renin receptor (PRR). We hypothesized that increasing PRR reduces autophagy and increases apoptosis of mouse podocytes exposed to high glucose via activation of the PI3K/Akt/mTOR signaling pathway. Mouse podocytes were cultured in normal (5 mmol/l) or high (25 mmol/l) d-glucose for 48 h. High glucose significantly increased mRNA and protein levels of PRR, phosphorylation of PI3K/Akt/mTOR, and p62. In contrast, high glucose decreased activation of UNC-51-like kinase-1 (ULK1) by phosphorylating Ser757 and protein levels of microtubule-associated protein-1 light chain 3B (LC3B)-II and Lamp-2. Bafilomycin A1 increased LC3BII and p62 accumulation in high-glucose-treated cells. High glucose reduced the autophagic flux. Confocal microscopy studies showed significant reduction in the protein level of LC3B in response to high glucose. Cyto-ID autophagy staining showed a significant decrease in autophagosome formation with high glucose. In the absence of PRR, activation of Akt with sc-79 or mTOR with MHY-1485 increased p62 accumulation. Caspase-3/7 activity and apoptosis monitored by TUNEL assay were significantly increased in podocytes treated with high glucose. PRR siRNA significantly reversed the effects of high glucose. Based on these data, we conclude that high glucose decreases autophagy and increases apoptosis in mouse podocytes through the PRR/PI3K/Akt/mTOR signaling pathway.

scholarly journals Carnosine Protects Mouse Podocytes from High Glucose Induced Apoptosis through PI3K/AKT and Nrf2 Pathways

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Kunxiao Zhao ◽  
Ying Li ◽  
Ziqiang Wang ◽  
Ning Han ◽  
Ying Wang
Keyword(s):  
Diabetic Nephropathy ◽  
Signaling Pathways ◽  
High Glucose ◽  
Pathological Process ◽  
Antioxidant Effect ◽  
Cell Counting ◽  
Ros Production ◽  
Oxygen Species ◽  
Quantitative Real Time Pcr ◽  
Induced Apoptosis

Diabetic nephropathy is the complication of diabetes mellitus that can lead to chronic renal failure. Reactive oxygen species (ROS) production plays an important role in its pathological process. Previous studies showed that carnosine may reduce diabetic nephropathy by antioxidant effect. However, the molecular mechanism of its antioxidant was not fully understood. In the current study, we developed high glucose containing different concentrations of carnosine to reduce ROS levels and podocytes apoptosis, and Cell Counting Kit-8 test was used to observe the cell viability. Carnosine (5-20mM) was found to protect mouse podocytes (MPC5) cells from HG-induced injury. Quantitative real-time PCR, Western blotting, and immunofluorescence staining revealed that high glucose induced ROS levels and podocytes apoptosis were downregulated by PI3K/AKT and Nrf2 signaling pathways. The current findings suggest that carnosine may reduce ROS levels and MPC5 cells apoptosis by PI3K/AKT and Nrf2 signaling pathways activation.

scholarly journals Alleviation by Mahuang Fuzi and Shenzhuo Decoction in High Glucose-Induced Podocyte Injury by Inhibiting the Activation of Wnt/β-Catenin Signaling Pathway, Resulting in Activation of Podocyte Autophagy

2020 ◽  
Vol 2020 ◽  
pp. 1-11
Author(s):  
Haoran Dai ◽  
Fei Liu ◽  
Xinping Qiu ◽  
Wenbin Liu ◽  
Zhaocheng Dong ◽  
...  
Keyword(s):  
Signaling Pathway ◽  
High Glucose ◽  
Protective Mechanism ◽  
Podocyte Injury ◽  
Common Endpoint ◽  
Protein Expressions ◽  
Related Proteins ◽  
The Relationship ◽  
Excessive Activation ◽  
Organ Fibrosis

Background. Organ fibrosis is a common endpoint of a variety of diseases. Many studies have shown that the pathogenesis of diabetic kidney disease (DKD) is related to the excessive activation of the Wnt/β-catenin signaling pathway on podocytes, so the treatment of DKD starts from this signaling pathway. At the same time, DKD, as a metabolic disease, has many connections related to podocyte autophagy. Objectives. We experimented the effects of Mahuang Fuzi and Shenzhuo decoction (MFSD) which is the combination of Mahuang Fuzi decoction and Shenzhuo decoction in traditional Chinese medicine compounds used “The Golden Chamber” in high glucose-induced podocytes, determined whether this effect was related to Wnt/β-catenin signaling pathway, and further investigated the relationship between this effect and autophagy. Methods. The mice podocytes were stimulated by using 30 mmol/L of high glucose and serum containing MFSD or Wnt/β-catenin signaling pathway inhibitor DKK1 (100 ng/ml) was used to intervene podocytes before high glucose stimulation. Podocyte injury-related proteins, Wnt/β-catenin signaling pathway-related proteins, and autophagy-related proteins were detected by using western blotting and immunofluorescence analysis. Results. Our results showed that DKK1 and MFSD treatment significantly upregulated the protein expressions of nephrin, podocin, podocalyxin, and podoplanin in high glucose-induced podocytes and downregulated the β-catenin protein expression. Furthermore, the protein expressions of beclin1, LC3B, and P62 were also significantly increased in high glucose-induced podocytes. Conclusion. Our experiments confirmed that the destruction of podocytes in DKD is related to the excessive activation of Wnt/β-catenin signaling pathway and the inhibition of autophagy after activation. MFSD treatment can inhibit the activation of Wnt/β-catenin signaling pathway in podocytes stimulated by high glucose and helpful in reducing the podocyte injury. This protective mechanism can be related to the enhancement of podocyte autophagy by MFSD treatment.

Silencing of KPNA2 inhibits high glucose-induced podocyte injury via inactivation of mTORC1/p70S6K signaling pathway

2020 ◽  
Vol 521 (4) ◽  
pp. 1017-1023 ◽  
Author(s):  
Xiaobao Fan ◽  
Zhenjiang Li ◽  
Xiaoming Wang ◽  
Jing Wang ◽  
Zhiming Hao
Keyword(s):  
Signaling Pathway ◽  
High Glucose ◽  
Podocyte Injury

scholarly journals Upregulation ofα3β1-Integrin in Podocytes in Early-Stage Diabetic Nephropathy

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Kaichiro Sawada ◽  
Masao Toyoda ◽  
Noriko Kaneyama ◽  
Sawako Shiraiwa ◽  
Hitomi Moriya ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
Early Stage ◽  
Integrin Expression ◽  
Advanced Stage ◽  
Podocyte Injury ◽  
Expression Levels ◽  
Podocyte Detachment ◽  
Advanced Stages

Background. Podocyte injury plays an important role in the onset and progression of diabetic nephropathy (DN). Downregulation ofα3β1-integrin expression in podocytes is thought to be associated with podocyte detachment from the glomerular basement membrane, although the mechanisms remain obscure. To determine the mechanism of podocyte detachment, we analyzed the expression levels ofα3β1-integrin in podocytes in early and advanced stages of DN.Methods. Surgical specimens from DN patients were examined byin situhybridization, and the expression levels ofα3- andβ1-integrin subunits in glomeruli of early (n=6) and advanced (n=8) stages were compared with those of normal glomeruli (n=5). Heat-sensitive mouse podocytes (HSMP) were cultured with TGF-β1 to reproduce the microenvironment of glomeruli of DN, and the expression levels of integrin subunits and the properties of migration and attachment were examined.Results. Podocytes of early-stage DN showed upregulation ofα3- andβ1-integrin expression while those of advanced stage showed downregulation. Real-time PCR indicated a tendency for upregulation ofα3- andβ1-integrin in HSMP cultured with TGF-β1. TGF-β1-stimulated HSMP also showed enhancedin vitromigration and attachment on collagen substrate.Conclusions. The results suggested that podocyte detachment during early stage of DN is mediated through upregulation ofα3β1-integrin.

scholarly journals Hydrogen Sulfide Ameliorates High Glucose-induced Inflammation Through SIRT1-mTOR/NF-κB Signaling Pathway in HT-22 cells

2020 ◽  
Author(s):  
Xinrui Li ◽  
Yinghua Yu ◽  
Peiquan Yu ◽  
Ting Xu ◽  
Jiao Liu ◽  
...  
Keyword(s):  
Hydrogen Sulfide ◽  
Inflammatory Response ◽  
Signaling Pathway ◽  
High Glucose ◽  
Near Infrared ◽  
Neuronal Cell ◽  
Inflammatory Factors ◽  
Sodium Hydrosulfide ◽  
Protein Levels

Abstract Background: Hyperglycemia-induced neuroinflammation promotes the progression of diabetic encephalopathy (DE). Hydrogen sulfide (H2S) exerts anti-inflammatory and neuroprotective activities against neurodegenerative diseases. However, its role in hyperglycemia-induced neuronal inflammation has not been investigated. Herein, we examined the effects and its related signaling pathway of H2S on inflammatory response in high glucose-treated HT-22 cells.Methods: A hippocampal neuronal cell line, HT-22, was used as an in vitro model to explore the function of H2S on inflammatory response triggered by high glucose. A dicyanoisophorone-based near-infrared fluorescent probe (NIR-NP) was synthesized to detect H2S levels in HT-22 cells. Western blotting, immunofluorescence and real time-qPCR were carried out to study the mechanism of action for H2S.Results: We found that high glucose (85 mM) decreased the level of endogenous H2S and the expression of cystathionine-β-synthase (CBS) which is the main enzyme for H2S production in the brain. Sodium hydrosulfide (NaHS, a H2S donor) or S-adenosylmethionine (SAMe, an allosteric activator of CBS) administration restored high glucose-induced downregulation of CBS and H2S levels. Importantly, high glucose upregulated the level of pro-inflammatory factors (IL-1β, IL-6, TNF-α) in HT-22 cells. Treatment with NaHS or SAMe alleviated this enhanced transcription of these pro-inflammatory factors, suggesting that H2S might ameliorate high glucose-induced inflammation in HT-22 cells. We also found that high glucose reduced SIRT1 protein levels. SIRT1 reduction elevated the level of p-mTOR, p-NF-κB and pro-inflammatory factors, which were restored by resveratrol (a SIRT1 agonist). These results suggested that SIRT1 might be an upstream mediator of mTOR/NF-κB signaling pathway. Furthermore, NaHS or SAMe treatment reversed the expression of SIRT1, mTOR and NF-κB under high glucose conditions.Conclusions: Our study revealed that high glucose decreased CBS to reduce the production of H2S, which in turn decreased the expression of SIRT1. The reduction of SIRT1 activated mTOR/NF-κB signaling to promote inflammation. Given that promoting H2S production using NaHS or SAMe can reverse high glucose-induced inflammatory response, our study might shed light on the prophylactic treatment of DE.

scholarly journals MicroRNA-27a targets Sfrp1 to induce renal fibrosis in diabetic nephropathy by activating Wnt/β-Catenin signalling

2020 ◽  
Vol 40 (6) ◽  
Author(s):  
MingJun Shi ◽  
PingPing Tian ◽  
ZhongQiang Liu ◽  
Fan Zhang ◽  
YingYing Zhang ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
High Glucose ◽  
Renal Fibrosis ◽  
Negative Control ◽  
Luciferase Reporter ◽  
Mrna Levels ◽  
Expression Levels ◽  
Stage Renal Disease

Abstract Diabetic nephropathy (DN) commonly causes end-stage renal disease (ESRD). Increasing evidence indicates that abnormal miRNA expression is tightly associated with chronic kidney disease (CKD). This work aimed to investigate whether miR-27a can promote the occurrence of renal fibrosis in DN by suppressing the expression of secreted frizzled-related protein 1 (Sfrp1) to activate Wnt/β-catenin signalling. Therefore, we assessed the expression levels of miR-27a, Sfrp1, Wnt signalling components, and extracellular matrix (ECM)-related molecules in vitro and in vivo. Sfrp1 was significantly down-regulated in a high-glucose environment, while miR-27a levels were markedly increased. A luciferase reporter assay confirmed that miR-27a down-regulated Sfrp1 by binding to the 3′ untranslated region directly. Further, NRK-52E cells under high-glucose conditions underwent transfection with miR-27a mimic or the corresponding negative control, miR-27a inhibitor or the corresponding negative control, si-Sfrp1, or combined miR-27a inhibitor and si-Sfrp1. Immunoblotting and immunofluorescence were performed to assess the relative expression levels of Wnt/β-catenin signalling and ECM components. The mRNA levels of Sfrp1, miR-27a, and ECM-related molecules were also detected by quantitative real-time PCR (qPCR). We found that miR-27a inhibitor inactivated Wnt/β-catenin signalling and reduced ECM deposition. Conversely, Wnt/β-catenin signalling was activated, while ECM deposition was increased after transfection with si-Sfrp1. Interestingly, miR-27a inhibitor attenuated the effects of si-Sfrp1. We concluded that miR-27a down-regulated Sfrp1 and activated Wnt/β-catenin signalling to promote renal fibrosis.

scholarly journals Hyperoside Alleviates High Glucose-Induced Proliferation of Mesangial Cells through the Inhibition of the ERK/CREB/miRNA-34a Signaling Pathway

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Le Zhang ◽  
Qian Dai ◽  
Lanlan Hu ◽  
Hua Yu ◽  
Jing Qiu ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
Signaling Pathway ◽  
High Glucose ◽  
Mesangial Cells ◽  
Viable Cell ◽  
Underlying Mechanism ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Dependent Manner ◽  
Glomerular Mesangial Cells

Purpose. Hyperoside, a flavonoid isolated from conventional medicinal herbs, has been demonstrated to exert a significant protective effect in diabetic nephropathy. This study aimed to determine the underlying mechanisms, by which hyperoside inhibits high glucose-(HG-) induced proliferation in mouse renal mesangial cells. Methods. Mouse glomerular mesangial cells line (SV40-MES13) was used to study the inhibitory effect of hyperoside on cell proliferation induced by 30 mM glucose, which was used to simulate a diabetic condition. Viable cell count was assessed using the Cell Counting Kit-8 and by the 5-ethynyl-20-deoxyuridine incorporation assay. The underlying mechanism involving miRNA-34a was further investigated by quantitative RT-PCR and transfection with miRNA-34a agomir. The phosphorylation levels of extracellular signal-regulated kinases (ERKs) and cAMP-response element-binding protein (CREB) were measured by Western blotting. The binding region and the critical binding sites of CREB in the miRNA-34a promoter were investigated by the chromatin immunoprecipitation assay and luciferase reporter assay, respectively. Results. We found that hyperoside could significantly decrease HG-induced proliferation of SV40-MES13 cells in a dose-dependent manner, without causing obvious cell death. In addition, hyperoside inhibited the activation of ERK pathway and phosphorylation of its downstream transcriptional factor CREB, as well as the miRNA-34a expression. We further confirmed that CREB-mediated regulation of miRNA-34a is dependent on the direct binding to specific sites in the promoter region of miRNA-34a. Conclusion. Our cumulative results suggested that hyperoside inhibits the proliferation of SV40-MES13 cells through the suppression of the ERK/CREB/miRNA-34a signaling pathway, which provides new insight to the current investigation on therapeutic strategies for diabetic nephropathy.

scholarly journals Podocyte EGFR Inhibits Autophagy Through Upregulation of Rubicon in Type II Diabetic Nephropathy

2020 ◽  
Author(s):  
Yan Li ◽  
Yu Pan ◽  
Shirong Cao ◽  
Kensuke Sasaki ◽  
Yinqiu Wang ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
High Glucose ◽  
Growth Factor Receptor ◽  
Type Ii ◽  
Egfr Signaling ◽  
Podocyte Injury ◽  
Egfr Signaling Pathway ◽  
Epidermal Growth ◽  
Sirna Knockdown ◽  
Autophagy Activity

Renal epidermal growth factor receptor (EGFR) signaling is activated in models of diabetic nephropathy (DN), and inhibition of EGFR signaling pathway protects against the development of DN. We have now determined that in cultured podocytes, high glucose led to increases in activation of EGFR signaling but decreases in autophagy activity as indicated by decreased beclin-1 and inhibition of LC3B autophagosome formation as well as increased rubicon (an autophagy inhibitor) and SQSTM1 (autophagy substrate). Either genetic (siEGFR) or pharmacologic (AG1478) inhibition of EGFR signaling attenuated the decreased autophagy activity. In addition, rubicon siRNA knockdown prevented high glucose-induced inhibition of autophagy in podocytes. We further examined whether selective EGFR deletion in podocytes affected the progression of DN in type II diabetes. Selective podocyte EGFR deletion had no effect on body weight or fasting blood sugars in either <i>db/db</i> mice or <i>nos3</i><sup>-/-</sup>; <i>db/db </i>mice, a model of accelerated type II DN. However selective podocyte EGFR deletion led to relative podocyte preservation and marked reduction in albuminuria and glomerulosclerosis, renal proinflammatory cytokine/chemokine expression and decreased pro-fibrotic and fibrotic components in <i>nos3</i><sup>-/-</sup>; <i>db/db</i> mice. Podocyte EGFR deletion led to decreased podocyte expression of rubicon, in association with increased podocyte autophagy activity. Therefore, activation of EGFR signaling in podocytes contributes to progression of DN at least in part by increasing rubicon expression, leading to subsequent autophagy inhibition and podocyte injury.

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