Reactive oxygen species-initiated autophagy opposes aldosterone-induced podocyte injury

2016 ◽  
Vol 310 (7) ◽  
pp. F669-F678 ◽  
Author(s):  
Mi Bai ◽  
Ruochen Che ◽  
Yue Zhang ◽  
Yanggang Yuan ◽  
Chunhua Zhu ◽  
...  

Evidence has demonstrated that aldosterone (Aldo) is involved in the development and progression of chronic kidney diseases. The purpose of the present study was to investigate the role of autophagy in Aldo-induced podocyte damage and the underlying mechanism. Mouse podocytes were treated with Aldo in the presence or absence of 3-methyladenine and N-acetylcysteine. Cell apoptosis was investigated by detecting annexin V conjugates, apoptotic bodies, caspase-3 activity, and alterations of the podocyte protein nephrin. Autophagy was evaluated by measuring the expressions of light chain 3, p62, beclin-1, and autophagy-related gene 5. Aldo (10−7 mol/l) induced podocyte apoptosis, autophagy, and downregulation of nephrin protein in a time-dependent manner. Aldo-induced apoptosis was further promoted by the inhibition of autophagy via 3-methyladenine and autophagy-related gene 5 small interfering RNA pretreatment. Moreover, Aldo time dependently increased ROS generation, and H2O2 (10−4 mol/l) application remarkably elevated podocyte autophagy. After treatment with N-acetylcysteine, the autophagy induced by Aldo or H2O2 was markedly attenuated, suggesting a key role of ROS in mediating autophagy formation in podocytes. Inhibition of ROS could also lessen Aldo-induced podocyte injury. Taken together, our findings suggest that ROS-triggered autophagy played a protective role against Aldo-induced podocyte injury, and targeting autophagy in podocytes may represent a new therapeutic strategy for the treatment of podocytopathy.

2017 ◽  
Vol 312 (4) ◽  
pp. F589-F598 ◽  
Author(s):  
Yan Guo ◽  
Xu Deng ◽  
Shuang Chen ◽  
Lingyun Yang ◽  
Jiajia Ni ◽  
...  

MicroRNAs are essential for the maintenance of podocyte homeostasis. Emerging evidence has demonstrated a protective role of microRNA-30a (miR-30a), a member of the miR-30 family, in podocyte injury. However, the roles of other miR-30 family members in podocyte injury are unclear. The present study was undertaken to investigate the contribution of miR-30e to the pathogenesis of podocyte injury induced by aldosterone (Aldo), as well as the underlying mechanism. After Aldo treatment, miR-30e was reduced in a dose-and time-dependent manner. Notably, overexpression of miR-30e markedly attenuated Aldo-induced apoptosis in podocytes. In agreement with this finding, miR-30e silencing led to significant podocyte apoptosis. Mitochondrial dysfunction (MtD) has been shown to be an early event in Aldo-induced podocyte injury. Here we found that overexpression of miR-30e improved Aldo-induced MtD while miR-30e silencing resulted in MtD. Next, we found that miR-30e could directly target the BCL2/adenovirus E1B-interacting protein 3-like (BNIP3L) gene. Aldo markedly enhanced BNIP3L expression in podocytes, and silencing of BNIP3L largely abolished Aldo-induced MtD and cell apoptosis. On the contrary, overexpression of BNIP3L induced MtD and apoptosis in podocytes. Together, these findings demonstrate that miR-30e protects mitochondria and podocytes from Aldo challenge by targeting BNIP3L.


2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Wenzhou Huang ◽  
Peng Ao ◽  
Jian Li ◽  
Tianlong Wu ◽  
Libiao Xu ◽  
...  

Aging is one of the most prominent risk factors for the pathological progression of osteoarthritis (OA). One feature of age-related changes in OA is advanced glycation end products (AGEs) accumulation in articular cartilage. Autophagy plays a cellular housekeeping role by removing dysfunctional cellular organelles and proteins. However, the relationship between autophagy and AGE-associated OA is unknown. The aim of this study is to determine whether autophagy participates in the pathology of AGE-treated chondrocytes and to investigate the exact role of autophagy in AGE-induced cell apoptosis and expression of matrix metalloproteinase- (MMP-) 3 and MMP-13. AGEs induced notable apoptosis that was detected by Annexin V/PI double-staining, and the upregulation of MMP-3 and MMP-13 was confirmed by Western blotting. Autophagy-related proteins were also determined by Western blotting, and chondrocytes were transfected with mCherry-GFP-LC3B-adenovirus to monitor autophagic flux. As a result, autophagy significantly increased in chondrocytes and peaked at 6 h. Furthermore, rapamycin (RA) attenuated AGE-induced apoptosis and expression of MMP-3 and MMP-13 by autophagy activation. In contrast, pretreatment with autophagy inhibitor 3-methyladenine (3-MA) enhanced the abovementioned effects of AGEs. We therefore demonstrated that autophagy is linked with AGE-related pathology in rat chondrocytes and plays a protective role in AGE-induced apoptosis and expression of MMP-3 and MMP-13.


2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Jianlei Zhang ◽  
Wei Liu ◽  
Yabo Wang ◽  
Shengnan Zhao ◽  
Na Chang

miR-135a-5p was reported to play a crucial role in the protective effects of hydrogen sulfide against Parkinson’s disease (PD) by targeting rho-associated protein kinase 2 (ROCK2). However, the role of another member of miR-135 family (miR-135b) and the underlying mechanism in PD are still unclear. qRT-PCR and western blot showed that miR-135 was downregulated and glycogen synthase kinase 3β (GSK3β) was upregulated at mRNA and protein levels in MPP+-intoxicated SH-SY5Y cells in a dose- and time-dependent manner. MTT, TUNEL, and ELISA assays revealed that miR-135b overexpression significantly promoted cell proliferation and inhibited apoptosis and production of TNF-α and IL-1β in SH-SY5Y cells in the presence of MPP+. Luciferase reporter assay demonstrated that GSK3β was a direct target of miR-135b. Moreover, sodium nitroprusside (SNP), a GSK3β activator, dramatically reversed the effects of miR-135b upregulation on cell proliferation, apoptosis, and inflammatory cytokine production in MPP+-intoxicated SH-SY5Y cells. Taken together, miR-135b exerts a protective role via promotion of proliferation and suppression of apoptosis and neuroinflammation by targeting GSK3β in MPP+-intoxicated SH-SY5Y cells, providing a potential therapeutic target for the treatment of PD.


2021 ◽  
pp. ASN.2020071076 ◽  
Author(s):  
Federica Barutta ◽  
Shunsuke Kimura ◽  
Koji Hase ◽  
Stefania Bellini ◽  
Beatrice Corbetta ◽  
...  

BackgroundPodocyte dysfunction and loss are major determinants in the development of proteinuria. FSGS is one of the most common causes of proteinuria, but the mechanisms leading to podocyte injury or conferring protection against FSGS remain poorly understood. The cytosolic protein M-Sec has been involved in the formation of tunneling nanotubes (TNTs), membrane channels that transiently connect cells and allow intercellular organelle transfer. Whether podocytes express M-Sec is unknown and the potential relevance of the M-Sec–TNT system in FSGS has not been explored.MethodsWe studied the role of the M-Sec–TNT system in cultured podocytes exposed to Adriamycin and in BALB/c M-Sec knockout mice. We also assessed M-Sec expression in both kidney biopsies from patients with FSGS and in experimental FSGS (Adriamycin-induced nephropathy).ResultsPodocytes can form TNTs in a M-Sec–dependent manner. Consistent with the notion that the M-Sec–TNT system is cytoprotective, podocytes overexpressed M-Sec in both human and experimental FSGS. Moreover, M-Sec deletion resulted in podocyte injury, with mitochondrial abnormalities and development of progressive FSGS.In vitro, M-Sec deletion abolished TNT-mediated mitochondria transfer between podocytes and altered mitochondrial bioenergetics. Re-expression of M-Sec reestablishes TNT formation and mitochondria exchange, rescued mitochondrial function, and partially reverted podocyte injury.ConclusionsThese findings indicate that the M-Sec–TNT system plays an important protective role in the glomeruli by rescuing podocytesviamitochondrial horizontal transfer. M-Sec may represent a promising therapeutic target in FSGS, and evidence that podocytes can be rescuedviaTNT-mediated horizontal transfer may open new avenues of research.


2020 ◽  
Author(s):  
Liye Chen ◽  
Lili Wei ◽  
Qiongyang Yu ◽  
Haozhe Shi ◽  
George Liu

Abstract Background: Acute myocardial infarction (AMI) is the leading cause of death globally and has thus placed a heavy burden on healthcare. Tanshinone IIA (TSA) is a major active compound, extracted from Salvia miltiorrhiza Bunge, that possesses various pharmacological activities. The aim of the present study was to investigate the role of TSA in AMI and its underlying mechanism of action.Results: We have shown that TSA decreased the apoptosis rate, the amount of LDH, MDA as well as ROS of cardiomyocytes. Meantime, it elevated mitochondrial membrane potential (MMP) which was decreased by H/R treatment. It was also determined that miR-124-5p targets AK003290 directly. TSA up-regulated the expression of AK003290 and its function can be reversed by knock down of AK003290 as well as miR-124-5p overexpression.Conclusion: TSA exerts the protective role against H/R induced apoptosis, oxidative and MMP loss of cardiomyocytes via regulating AK003290 and miR-124-5p signaling.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4478-4478
Author(s):  
Julia Mazar ◽  
Alexandra Lichtenstein ◽  
Leora Katz ◽  
Ofer Shpilberg ◽  
Itai Levi ◽  
...  

Abstract Many types of antitumor therapy in general and AML in particular exert their effect by activating apoptosis. Apoptosis of AML cells can be induced by cytostatic drugs, corticosteroids, and radiation. Recently, the role of different proteases as possible targets for chemotherapy was described. N-tosyl-L-phenylalanine chloromethyl ketone (TPCK), a chymotrypsin-like protease (CLP) inhibitor was shown to exert a dual effect on leukemic cells: proapoptotic and antiapoptotic. In the present study the mechanism of its proapoptotic effect was addressed. It was found that the CLP inhibitors, TPCK and 3,4 dichloroisicoumarine induced apoptosis in a time- and concentration-dependent manner. Apoptosis was accompanied by a decrease in mitochondrial membrane potential, cytochrome c release, caspase-3 (but not caspase-8) activation, PS flip-flop (measured by Annexin-V staining followed by flow cytometry analysis) and chromatin condensation, but not fragmentation (detected by acridine orange/ethidium bromide staining). All apoptotic processes induced by TPCK were completely inhibited by cycloheximide. The ability of cycloheximide to inhibit TPCK-induced cell death suggests that protein synthesis plays a role in TPCK-induced apoptosis. Additionaly, the proapoptotic effect of TPCK was abolished by elimination of glucose from the medium. The data supports the role of mitochondria in this process. In the present study the apoptotic pathway driven by inhibition of CLP was demonstrated. Moreover, these findings suggest possible ways of preventing the proapoptotic activity of TPCK and thereby enhancimg its antiapoptotic action.


2019 ◽  
Author(s):  
Liye Chen ◽  
Lili Wei ◽  
Qiongyang Yu ◽  
Haozhe Shi ◽  
George Liu

Abstract Objective Acute myocardial infarction (AMI) is the leading cause of death and one of the heaviest healthy burden globally nowadays. Tanshinone IIA (TSA) is the major active compound extracted form Salvia miltiorrhiza Bunge possessing various of pharmacology activities. The present study aimed at investigating the role of TSA in AMI and underlying mechsniam.Methods Quantitative real-time PCR (qRT-PCR) and western blot assay were performed to detect the expression of genes and proteins. Cell apoptosis was detected by Annexin/V PI staining and flow cytometry. The amount of LDH, MDA and ROS were detected using commercial kits. FISH experiment was used to detect the expression of AK003290 in cardiomyocytes. Luciferace activity assay was performed to verify the interaction between AK003290 and miR-124-5p.Results We have shown that TSA decreased the apoptosis rate, the amount of LDH, MDA as well as ROS of cardiomyocytes. Meantime, it elevated mitochondrial membrane potential (MMP) which was decreased by H/R treatment. It was also determined that miR-124-5p targets AK003290 directly. TSA up-regulated the expression of AK003290 and its function can be reversed by knock down of AK003290 as well as miR-124-5p overexpression.Conclusion TSA exerts the protective role against H/R induced apoptosis, oxidative and MMP loss of cardiomyocytes via regulating AK003290 and miR-124-5p signaling.


2019 ◽  
Vol 63 (2) ◽  
pp. 151-159 ◽  
Author(s):  
Isabel Moscoso ◽  
María Cebro-Márquez ◽  
Moisés Rodríguez-Mañero ◽  
José Ramón González-Juanatey ◽  
Ricardo Lage

Irisin is a newly identified adipokine critical to modulate body metabolism, fatty acid metabolism and oxidative stress; recent evidence suggests a cardioprotective role in ischemic injury. Loss of cardiomyocytes during acute myocardial infarction is strongly associated with energetic changes and lipotoxic-induced apoptosis. Our aim was to study FNDC5/irisin’s potential protective role against hypoxia and lipotoxicity, both related with myocardial infarction environment. H9c2 cells were treated with palmitate and/or irisin in normoxic/hypoxic conditions. Cell viability and apoptosis were assessed by MTT assay and annexin V/PI staining. Immunoblotting was used to confirm apoptotic cascade regulation. Irisin counteracts lipotoxic-induced apoptosis in hypoxic cardiomyoblasts by activating Akt signaling pathway suggesting the potential therapeutic role of irisin in ischemic heart disease.


2020 ◽  
Author(s):  
Liye Chen ◽  
Lili Wei ◽  
Qiongyang Yu ◽  
Haozhe Shi ◽  
George Liu

Abstract Background: Acute myocardial infarction (AMI) is the leading cause of death globally and has thus placed a heavy burden on healthcare. Tanshinone IIA (TSA) is a major active compound, extracted from Salvia miltiorrhiza Bunge, that possesses various pharmacological activities. The aim of the present study was to investigate the role of TSA in AMI and its underlying mechanism of action.Results: We have shown that TSA decreased the apoptosis rate, the amount of LDH, MDA as well as ROS of cardiomyocytes. Meantime, it elevated mitochondrial membrane potential (MMP) which was decreased by H/R treatment. It was also determined that miR-124-5p targets AK003290 directly. TSA up-regulated the expression of AK003290 and its function can be reversed by knock down of AK003290 as well as miR-124-5p overexpression.Conclusion: TSA exerts the protective role against H/R induced apoptosis, oxidative and MMP loss of cardiomyocytes via regulating AK003290 and miR-124-5p signaling.


2019 ◽  
Vol 18 (10) ◽  
pp. 1448-1456 ◽  
Author(s):  
Bahareh Movafegh ◽  
Razieh Jalal ◽  
Zobeideh Mohammadi ◽  
Seyyede A. Aldaghi

Objective: Cell resistance to doxorubicin and its toxicity to healthy tissue reduce its efficiency. The use of cell-penetrating peptides as drug delivery system along with doxorubicin is a strategy to reduce its side effects. In this study, the influence of poly-L-arginine on doxorubicin cytotoxicity, its cellular uptake and doxorubicin-induced apoptosis on human prostate cancer DU145 cells are assessed. Methods: The cytotoxicity of doxorubicin and poly-L-arginine, alone and in combination, in DU145 cells was evaluated at different exposure times using MTT assay. The influence of poly-L-arginine on doxorubicin delivery into cells was evaluated by fluorescence microscopy and ultraviolet spectroscopy. DAPI and ethidium bromide- acridine orange stainings, flow cytometry using annexin V/propidium iodide, western blot analysis with anti-p21 antibody and caspase-3 activity were used to examine the influence of poly-L-arginine on doxorubicininduced cell death. Results: Poly-L-arginine had no cytotoxicity at low concentrations and short exposure times. Poly-L-arginine increased the cytotoxic effect of doxorubicin in DU145 cells in a time-dependent manner. But no significant reduction was found in HFF cell viability. Poly-L-arginine seems to facilitate doxorubicin uptake and increase its intracellular concentration. 24h combined treatment of cells with doxorubicin (0.5 µM) and poly-L-arginine (1 µg ml-1) caused a small increase in doxorubicin-induced apoptosis and significantly elevated necrosis in DU145 cells as compared to each agent alone. Conclusion: Our results indicate that poly-L-arginine at lowest and highest concentrations act as proliferationinducing and antiproliferative agents, respectively. Between these concentrations, poly-L-arginine increases the cellular uptake of doxorubicin and its cytotoxicity through induction of necrosis.


Sign in / Sign up

Export Citation Format

Share Document