scholarly journals PGC-1α inhibits the NLRP3 inflammasome via preserving mitochondrial viability to protect kidney fibrosis

2022 ◽  
Vol 13 (1) ◽  
Author(s):  
Bo Young Nam ◽  
Jong Hyun Jhee ◽  
Jimin Park ◽  
Seonghun Kim ◽  
Gyuri Kim ◽  
...  

AbstractThe NLRP3 inflammasome is activated by mitochondrial damage and contributes to kidney fibrosis. However, it is unknown whether PGC-1α, a key mitochondrial biogenesis regulator, modulates NLRP3 inflammasome in kidney injury. Primary renal tubular epithelial cells (RTECs) were isolated from C57BL/6 mice. The NLRP3 inflammasome, mitochondrial dynamics and morphology, oxidative stress, and cell injury markers were examined in RTECs treated by TGF-β1 with or without Ppargc1a plasmid, PGC-1α activator (metformin), and siPGC-1α. In vivo, adenine-fed and unilateral ureteral obstruction (UUO) mice were treated with metformin. In vitro, TGF-β1 treatment to RTECs suppressed the expressions of PGC-1α and mitochondrial dynamic-related genes. The NLRP3 inflammasome was also activated and the expression of fibrotic and cell injury markers was increased. PGC-1α induction with the plasmid and metformin improved mitochondrial dynamics and morphology and attenuated the NLRP3 inflammasome and cell injury. The opposite changes were observed by siPGC-1α. The oxidative stress levels, which are inducers of the NLRP3 inflammasome, were increased and the expression of TNFAIP3, a negative regulator of NLRP3 inflammasome regulated by PGC-1α, was decreased by TGF-β1 and siPGC-1α. However, PGC-1α restoration reversed these alterations. In vivo, adenine-fed and UUO mice models showed suppression of PGC-1α and TNFAIP3 and dysregulated mitochondrial dynamics. Moreover, the activation of oxidative stress and NLRP3 inflammasome, and kidney fibrosis were increased in these mice. However, these changes were significantly reversed by metformin. This study demonstrated that kidney injury was ameliorated by PGC-1α-induced inactivation of the NLRP3 inflammasome via modulation of mitochondrial viability and dynamics.

2020 ◽  
Vol 11 ◽  
Author(s):  
Hao Wang ◽  
Weiwei Xia ◽  
Guangfeng Long ◽  
Zhiyin Pei ◽  
Yuanyuan Li ◽  
...  

Cisplatin is extensively used and is highly effective in clinical oncology; nevertheless, nephrotoxicity has severely limited its widespread utility. Isoquercitrin (IQC), a natural flavonoid widely found in herbage, is well known and recognized for its antioxidant, anti-inflammatory, and anti-apoptotic properties. However, the potential effects and mechanism of IQC in cisplatin-induced acute kidney diseases remain unknown. In this study, we postulated the potential effects and mechanism of IQC upon cisplatin exposure in vivo and in vitro. For the in vivo study, C57BL/6J mice were pretreated with IQC or saline (50 mg/kg/day) by gavage for 3 days before cisplatin single injection (25 mg/kg). Renal function, apoptosis, inflammation, oxidative stress and p-ERK were measured to evaluate kidney injury. In vitro, mouse proximal tubular cells (mPTCs) and human proximal tubule epithelial cell line (HK2) were pretreated with or without IQC (80 μM for mPTCs and 120 μM for HK2) for 2 h and then co-administrated with cisplatin for another 24 h. Apoptosis, inflammation, ROS and p-ERK of cells were also measured. In vivo, IQC administration strikingly reduced cisplatin-induced nephrotoxicity as evidenced by the improvement in renal function (serum creatinine and blood urea nitrogen), kidney histology (PAS staining), apoptotic molecules (cleaved caspase-3, caspase-8, Bax and Bcl-2), inflammatory cytokines (IL-1β, IL-6, TNF-α, and COX-2), oxidative stress (MDA and total glutathione) and p-ERK. In line with in vivo findings, IQC markedly protected against cisplatin-induced cell injury in mPTCs and HK2 cells. Collectively, these findings demonstrated that IQC administration could significantly protect against cisplatin nephrotoxicity possibly through ameliorating apoptosis, inflammation and oxidative stress accompanied by cross talk with p-ERK. Furthermore, IQC may have potential therapeutic uses in the treatment of cisplatin-induced acute kidney injury.


2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 756-756
Author(s):  
Mingxia Jiang

Abstract Objectives Both oxidative stress (OS) and fibrosis play a significant role in the pathobiology of diabetic nephropathy (DN). Hence, we observed the effects of a-linolenic acids/linoleic acid (ALA/LA) on renal oxidative stress and tubule fibrosis on DN db/db mice and clarified its possible mechanisms in vivo. Methods db/db and db/m mice were divided into four groups, including normal control group(db/m mice), DN model group(DN db/db mice), low-dose group (DN db/db mice intervened by 250 mg/kg.d mixture of ALA and LA, with the ratio of 1:4), high-dose group (DN db/db mice intervened by500mg/kg.d ALA/LA, with the ratio of 1:4). The effect of ALA/LA on DN db/db mice analyzed by ELISA, realtime PCR, Westen Blot and pathophysiology methods. Results Compared to the DN model group, after ALA/LA intervention, fasting plasma glucose, renal function, inflammation factors, the level of oxidative stress and the degree renal pathological morphology damage of db/db mice were lower in the intervention group(P < 0.05). The SOD, CAT, MDA level (nmol/mgprot) in intervention group was 11.97 ± 1.95, 20.13 ± 1.67, 0.81 ± 0.12, and that in the model group was5.87 ± 1.87, 12.37 ± 1.50, 1.07 ± 0.10. BUN, SCr, UA in intervention group was 19.21 ± 6.16 mmol/L, 30.86 ± 5.37μmol/L, 230.14 ± 56.44μmol/L; and that in the model group was 9.74 ± 3.77 mmol/L, 22.22 ± 3.9μmol/L, 172.56 ± 27.32μmol/L.Intervention of ALA/LA decreased the protein and mRNA expression of TGF-β1, p-p38 (p38), p-ERK (ERK) and COLⅣ in kidney of db/db mice (P < 0.05). The relative mRNA level of TGF-β1, p38, ERK and COLⅣ in the intervention group was 0.64 ± 0.14, 2.71 ± 0.15, 2.48 ± 0.47, 4.37 ± 0.71, while that in the model group was17.63 ± 4.84, 127.43 ± 4.84, 15.91 ± 3.55, 32.05 ± 4.13.The relative protein level of TGF-β1, p-p38, p-ERK and COL-Ⅳ in the intervention group was 0.42 ± 0.07, 0.13 ± 0.04, 0.35 ± 0.04, and 0.46 ± 0.03, while that in the model group was 0.74 ± 0.05, 0.90 ± 0.03, 0.98 ± 0.02, 1.06 ± 0.10. Conclusions ALA/LA(1:4, 250 mg/kg/d) has good antioxidant capacity in vivo. It inhibited the transduction action of p38 and ERK, reduced the activity of TGF-β1, COL-Ⅳand ameliorate kidney fibrosis of DN db/db mice. The study on ALA/LA might provide research evidence and possible clinical treatment for DN. Funding Sources This work was financially supported by the National Natural Science Foundation of China (No. 81,372,986).


2018 ◽  
Vol 132 (12) ◽  
pp. 1297-1314 ◽  
Author(s):  
Ming Zhan ◽  
Irtaza Usman ◽  
Jingbo Yu ◽  
Liemin Ruan ◽  
Xueyan Bian ◽  
...  

Renal tubular injury is increasingly being recognized as an early characteristic of diabetic nephropathy (DN). Mitochondrial dynamic alterations and redox protein p66Shc-mediated oxidative stress are both critical for ensuing diabetic tubular cell injury and apoptosis; whether these two processes are interlinked remains unclear. In the present study, we observed changes in mitochondrial morphology and expression of associated proteins in tubules of patients with DN. We demonstrated mitochondrial fragmentation as an important pathogenic feature of tubular cell injury that is linked to oxidative stress and p66Shc up-regulation. In renal proximal tubular cells, alterations in mitochondrial dynamics and expression of fission–fusion proteins were observed under high glucose (HG) ambience, along with p66Shc Ser36 phosphorylation. Gene ablation of p66Shc alleviated HG-induced mitochondrial fragmentation, down-regulated Fis1 and reduced p66Shc–Fis1 binding, increased Mfn1 expression, and disrupted interactions between Mfn1 and proapoptotic Bak. Overexpression of p66Shc exacerbated these changes, whereas overexpression of dominant-negative p66Shc Ser36 mutant had a marginal effect under HG, indicating that p66Shc phosphorylation as a prerequisite in the modulation of mitochondrial dynamics. Disrupted mitochondrial dynamics and enhanced Mfn1–Bak interactions modulated by p66Shc led to loss of mitochondrial voltage potential, cytochrome C release, excessive ROS generation, and apoptosis. Taken together, these results link p66Shc to mitochondrial dynamic alterations in the pathogenesis of DN and unveil a novel mechanism by which p66Shc mediates HG-induced mitochondrial fragmentation and proapoptotic signaling that results in oxidative injury and apoptosis in the tubular compartment in human diabetic nephropathy.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Shiting Yu ◽  
Bing Han ◽  
Xin Xing ◽  
Yixuan Li ◽  
Daqing Zhao ◽  
...  

Leydig cell injury has been described as a primary driver of testicular dysfunction and is affected by oxidative stress. Dioscorea polystachya (Chinese yam) is used to improve testicular dysfunction in clinical and pharmacological research via its antioxidative activity, but the mechanisms underlying the beneficial effect of Chinese yam on testicular dysfunction and its suppression of Leydig cell oxidative damage remain unclear. In this study, we obtained a Chinese yam protein (DP1) and explored its effectiveness and possible mechanism in improving testicular dysfunction in vivo and in vitro. We established a testicular dysfunction model in rats using hydrocortisone (HCT). DP1 increased body weight and organ index, improved the deterioration in testicular morphology (including increasing the diameter of seminiferous tubules and thickness of germinal cell layers, inhibiting testicular cell apoptosis by increasing the Bcl-2/Bax ratio, and impeding collagen leakage by downregulating TGF-β1 and p-SMAD2/3 expression), and restored the testosterone content. In addition, DP1 enhanced the number of Leydig cells in rats and H2O2-induced TM3 Leydig cells, and the effect of DP1 on the apoptosis, fibrosis, and testosterone content of TM3 cells was similar to that observed in vivo. These changes were dependent on the regulation of oxidative stress, including significantly reduced intracellular 8-hydroxy-2-deoxyguanosine levels, enhanced superoxide dismutase activities, and decreased superoxide anion levels, which were confirmed via a superoxide overexpression system. Furthermore, we observed that DP1 promoted Nrf2 nuclear import and upregulated antioxidant factor expression in vivo and in vitro. However, Nrf2 silencing eliminated the ability of DP1 to increase the Bcl-2/Bax ratio, reduce the expression levels of TGF-β1 and p-SMAD2/3, and increase testosterone contents in H2O2-induced TM3 cells. In conclusion, DP1 reversed the HCT-induced testicular apoptosis and fibrosis and decreased testosterone contents by alleviating Leydig cell oxidative damage via upregulation of the Nrf2 pathway.


2018 ◽  
Vol 50 (3) ◽  
pp. 841-850 ◽  
Author(s):  
Hang Sun ◽  
Huihai Yang ◽  
Haonan Ruan ◽  
Wei Li ◽  
Xinhong He ◽  
...  

Background/Aims: Sika deer (Cervus nippon Temminck) antler is traditional animal medicine of renal protection in East Asia. This study measured the effect of sika deer antler protein (SDAPR) on gentamicin (GM)-induced cytotoxicity in HEK293 cells, and investigated the effect of SDAPR against GM-induced nephrotoxicity in mice. Methods: HEK293 cells viability and oxidative stress were measured in HEK293 cells while flow cytometry was used for apoptosis analysis. The acute kidney injury biomarkers, kidney injury molecule-1 (KIM-1), neutrophil gelatinase-associated lipocalin (NGAL) and cystatin c (Cys-C), were repeatedly measured by ELISA assay. ICR male mice were randomly assigned six groups: Control, GM with vehicle, single SDAPR, GM with SDAPR at three concentrations 50, 100, 200 mg/kg/d, p.o., 10 d. GM was injected for 8 consecutive days (100 mg/kg/d, i.p.). Renal function, oxidative stress and levels of inflammatory factors were measured in vivo. Renal tissues were stained with H&E to observe pathological changes. Results: Pretreatment with SDAPR (0.5-4.0 mg/mL) significantly improved cell viability. Treatment with SDAPR could reduce KIM-1, NGAL and Cys-C activity. SDAPR could improve antioxidant defense and attenuated apoptosis on HEK293 cells. SDAPR also ameliorated GM-induced histopathologic changes, and decreased blood urea nitrogen (BUN) and serum creatinine (Cr). Additionally, SDAPR significantly regulated oxidative stress marker and interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) inflammatory cytokines. Conclusion: These results show that SDAPR could be an effective dietary supplement to relieve GM-induced nephrotoxicity by improved antioxidase activity, suppressed inflammation, and inhibited apoptosis in vitro and vivo.


2019 ◽  
Vol 2 (4) ◽  
pp. e201900308 ◽  
Author(s):  
Shun Nagashima ◽  
Keisuke Takeda ◽  
Nobuhiko Ohno ◽  
Satoshi Ishido ◽  
Motohide Aoki ◽  
...  

Mitochondrial abnormalities are associated with developmental disorders, although a causal relationship remains largely unknown. Here, we report that increased oxidative stress in neurons by deletion of mitochondrial ubiquitin ligase MITOL causes a potential neuroinflammation including aberrant astrogliosis and microglial activation, indicating that mitochondrial abnormalities might confer a risk for inflammatory diseases in brain such as psychiatric disorders. A role of MITOL in both mitochondrial dynamics and ER-mitochondria tethering prompted us to characterize three-dimensional structures of mitochondria in vivo. In MITOL-deficient neurons, we observed a significant reduction in the ER-mitochondria contact sites, which might lead to perturbation of phospholipids transfer, consequently reduce cardiolipin biogenesis. We also found that branched large mitochondria disappeared by deletion of MITOL. These morphological abnormalities of mitochondria resulted in enhanced oxidative stress in brain, which led to astrogliosis and microglial activation partly causing abnormal behavior. In conclusion, the reduced ER-mitochondria tethering and excessive mitochondrial fission may trigger neuroinflammation through oxidative stress.


2021 ◽  
Author(s):  
Esmaeil Karami ◽  
Zahra Goodarzi ◽  
Ali Ghanbari ◽  
Ahmad Reza Bandegi ◽  
Sedighe Yosefi ◽  
...  

Abstract Purpose: Environmental and occupational exposure to cadmium chloride is known to cause nephrotoxicity linked with oxidative stress in humans and animals. This study used Atorvastatin to examine its effect on cadmium chloride-induced nephrotoxicity in rat model using biochemical and histological methodologies.Methods: Experiments were performed on 56 adult male Wistar rats (200 ±20 g), randomly assigned to eight groups. Atorvastatin was administered by oral for 15 days at 20 mg/kg/day, started 7 days before cadmium chloride intraperitoneal administration (1, 2, and 3 mg/kg) for eight days. On day 16, blood samples were collected, and kidneys were excised to evaluate the biochemical and histopathological changes.Cadmium chloride significantly increased malondialdehyde (MDA), serum creatinine (Cr), blood urea nitrogen (BUN), and decreased superoxide dismutase (SOD), glutathione (GSH), and glutathione peroxidase (GPx) levels. Results: Administration of Atorvastatin (20 mg/kg) significantly improved lipid peroxidation, glutathione and activities of antioxidant enzymes and significantly decreased BUN and Creatinine. Atorvastatin clearly improved the histological changes, demonstrating its protective role against Cadmium chloride-induced kidney injury.Conclusion: Treatment with Atorvastatin significantly improves all biochemical parameters and suggests a protecting role against cadmium chloride-induced oxidative stress and histological changes in rat kidney.


2021 ◽  
Vol 22 (19) ◽  
pp. 10822
Author(s):  
Agata Winiarska ◽  
Monika Knysak ◽  
Katarzyna Nabrdalik ◽  
Janusz Gumprecht ◽  
Tomasz Stompór

The incidence of type 2 diabetes (T2D) has been increasing worldwide, and diabetic kidney disease (DKD) remains one of the leading long-term complications of T2D. Several lines of evidence indicate that glucose-lowering agents prevent the onset and progression of DKD in its early stages but are of limited efficacy in later stages of DKD. However, sodium-glucose cotransporter-2 inhibitors (SGLT2i) and glucagon-like peptide-1 receptor (GLP-1R) antagonists were shown to exert nephroprotective effects in patients with established DKD, i.e., those who had a reduced glomerular filtration rate. These effects cannot be solely attributed to the improved metabolic control of diabetes. In our review, we attempted to discuss the interactions of both groups of agents with inflammation and oxidative stress—the key pathways contributing to organ damage in the course of diabetes. SGLT2i and GLP-1R antagonists attenuate inflammation and oxidative stress in experimental in vitro and in vivo models of DKD in several ways. In addition, we have described experiments showing the same protective mechanisms as found in DKD in non-diabetic kidney injury models as well as in some tissues and organs other than the kidney. The interaction between both drug groups, inflammation and oxidative stress appears to have a universal mechanism of organ protection in diabetes and other diseases.


2021 ◽  
Author(s):  
Xia Wang ◽  
Yinhua Wang ◽  
Guo Zhou ◽  
Yi Li ◽  
Huanhuan Huo ◽  
...  

Abstract Background Sepsis-associated acute kidney injury (S-AKI) is a frequent complication of critical patients and is associated with high morbidity and mortality. The glomerular endothelial cell injury is the main characteristics during S-AKI. Ca2+ influx is a key step in the establishment of endothelial injury. Transient receptor vanilloid subtype 4 (TRPV4) ion channels are permeable to Ca2+ and are widely expressed in endothelial cells. However, the role of TRPV4 on glomerular endothelial inflammation in S-AKI has remained elusive. Methods Mouse glomerular endothelial cells (MRGEC) were used to test the molecular mechanism of TRPV4 on LPS-induced glomerular endothelial inflammation. The cecal-ligation-and-puncture (CLP) model was established by ligation of cecum with 4-0 suture and punctured with a 21-gauge needle. Then 0.2mL faeces was extruded from the puncture site to trigger peritoneal inflammation. Results In the present study, we found that blocking TRPV4 diminishes LPS-induced cytosolic Ca2+-elevations, which are essential for glomerular endothelial inflammation and barrier function. Furthermore, TRPV4 regulated LPS-induced phosphorylation and translocation of NF-κB and IRF-3 in mouse glomerular endothelial cells (MRGEC). Clamping intracellular Ca2+ mimics the LPS-induce response seen in the absence of TRPV4. In vivo, pharmacological blockade or knock down of TRPV4 reduced the inflammatory response of glomerular endothelial cells, inhibited translocation of NF-κB and IRF-3, increased survival rate and improved renal function in CLP-induced sepsis but without altering renal cortical blood perfusion. Conclusions Taken together, these results suggested that inhibition of TRPV4 ameliorates glomerular endothelial inflammation, kidney dysfunction, and increased mortality via mediating Ca2+ overload and NF-κB/IRF-3 activation. These discoveries may provide novel pharmacological strategies for the treatment of glomerular endothelial dysfunction and kidney injury during endotoxemia, sepsis, and other inflammatory diseases.


2021 ◽  
Vol 14 ◽  
Author(s):  
Adeleh Sahebnasagh ◽  
Fatemeh Saghafi ◽  
Saeed Azimi ◽  
Ebrahim Salehifar ◽  
Seyed Jalal Hosseinimehr

: More than half of cancer patients need radiotherapy during the course of their treatment. Despite the beneficial aspects, the destructive effects of radiation beams on normal tissues lead to oxidative stress, inflammation, and cell injury. Kidneys are affected during radiotherapy of abdominal malignancies. Radiation nephropathy eventually leads to the release of factors triggering systemic inflammation. Currently, there is no proven prophylactic or therapeutic intervention for the management of radiation-induced nephropathy. This article reviews the biomarkers involved in the pathophysiology of radiation-induced nephropathy and its underlying molecular mechanisms. The efficacy of compounds with potential radio-protective properties on amelioration of inflammation and oxidative stress is also discussed. By outlining the approaches for preventing and treating this critical side effect, we evaluate the potential treatment of radiation-induced nephropathy. Available preclinical and clinical studies on these compounds are also scrutinized.


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