Zhen-Wu-Tang Induced Mitophagy to Protect Mitochondrial Function in Chronic Glomerulonephritis via PI3K/AKT/mTOR and AMPK Pathways

Chronic glomerulonephritis (CGN) is one of the major causes of end-stage kidney disease. Zhen-wu-tang (ZWT), as a famous Chinese herbal prescription, is widely used in China for CGN therapy in clinic. However, the mechanism of ZWT in CGN has not been fully understood. The present study explored the therapeutic effect and the underlying mechanism of ZWT on mitochondrial function in cationic bovine serum albumin (C-BSA)-induced CGN model rats and tumor necrosis factor (TNF-α)-damaged mouse podocytes. The renal functions were measured by serum creatinine (Scr) and blood urea nitrogen (BUN). Renal pathological changes and ultrastructure of kidney tissues were evaluated by periodic acid-Schiff (PAS) staining and transmission electron microscopy. The levels of antioxidases, including mitochondrial catalase (CAT), superoxide dismutase 2 (SOD2), and peroxiredoxin 3 (PRDX3), in CGN rats were examined by real-time PCR. The mitochondrial functions of podocytes were measured by ATP concentration, mitochondrial membrane potential (MMP), and mitochondrial ROS (mtROS). For mitophagy level detection, the expressions of mitophagy-related proteins, including LC3, p62, heat shock protein 60 (HSP60), and translocase of outer mitochondrial membrane 20 (TOMM20), were measured by Western blot, as the colocation of LC3 and mitochondrial marker COX IV were evaluated by immunofluorescence. Our results manifested that ZWT ameliorated CGN model rats by a remarkable decrease in Scr and BUN, inhibition of mesangial matrix proliferation, protection against foot processes fusion, and basement membrane thickening. More importantly, ZWT protected against mitochondrial dysfunction by increasing the expressions of CAT, SOD2, and PRDX3 in CGN model rats, increased ATP content and MMP in podocytes, and decreased excessive mtROS. Furthermore, ZWT induced mitophagy in CGN through increasing the expression of LC3, and decreasing p62, HSP60, TOMM20, and ZWT also enhanced the colocation of LC3 to the mitochondria. We found that ZWT inhibited the PI3K/AKT/mTOR pathway, which could be disturbed by PI3K inhibitor LY294002 and agonist insulin-like growth factor 1. Moreover, ZWT reversed the inhibition of the AMPK pathway in CGN. Overall, ZWT ameliorated renal mitochondrial dysfunction probably by inducing mitophagy via the PI3K/AKT/mTOR and AMPK pathways.

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Alpha-Tocotrienol Prevents Oxidative Stress-Mediated Post-Translational Cleavage of Bcl-xL in Primary Hippocampal Neurons

International Journal of Molecular Sciences ◽

10.3390/ijms21010220 ◽

2019 ◽

Vol 21 (1) ◽

pp. 220 ◽

Cited By ~ 4

Author(s):

Han-A Park ◽

Nelli Mnatsakanyan ◽

Katheryn Broman ◽

Abigail U. Davis ◽

Jordan May ◽

...

Keyword(s):

Membrane Potential ◽

Mitochondrial Dysfunction ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Function ◽

Hippocampal Neurons ◽

Mitochondrial Membrane ◽

Antioxidant Properties ◽

B Cell Lymphoma ◽

Atp Depletion ◽

Primary Hippocampal Neurons

B-cell lymphoma-extra large (Bcl-xL) is an anti-apoptotic member of the Bcl2 family of proteins, which supports neurite outgrowth and neurotransmission by improving mitochondrial function. During excitotoxic stimulation, however, Bcl-xL undergoes post-translational cleavage to ∆N-Bcl-xL, and accumulation of ∆N-Bcl-xL causes mitochondrial dysfunction and neuronal death. In this study, we hypothesized that the generation of reactive oxygen species (ROS) during excitotoxicity leads to formation of ∆N-Bcl-xL. We further proposed that the application of an antioxidant with neuroprotective properties such as α-tocotrienol (TCT) will prevent ∆N-Bcl-xL-induced mitochondrial dysfunction via its antioxidant properties. Primary hippocampal neurons were treated with α-TCT, glutamate, or a combination of both. Glutamate challenge significantly increased cytosolic and mitochondrial ROS and ∆N-Bcl-xL levels. ∆N-Bcl-xL accumulation was accompanied by intracellular ATP depletion, loss of mitochondrial membrane potential, and cell death. α-TCT prevented loss of mitochondrial membrane potential in hippocampal neurons overexpressing ∆N-Bcl-xL, suggesting that ∆N-Bcl-xL caused the loss of mitochondrial function under excitotoxic conditions. Our data suggest that production of ROS is an important cause of ∆N-Bcl-xL formation and that preventing ROS production may be an effective strategy to prevent ∆N-Bcl-xL-mediated mitochondrial dysfunction and thus promote neuronal survival.

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Garlic extract attenuates brain mitochondrial dysfunction and cognitive deficit in obese-insulin resistant rats

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2014-0255 ◽

2014 ◽

Vol 39 (12) ◽

pp. 1373-1379 ◽

Cited By ~ 18

Author(s):

Hiranya Pintana ◽

Jirapas Sripetchwandee ◽

Luerat Supakul ◽

Nattayaporn Apaijai ◽

Nipon Chattipakorn ◽

...

Keyword(s):

Body Weight ◽

Cognitive Function ◽

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Visceral Fat ◽

Cognitive Deficit ◽

Garlic Extract ◽

Insulin Resistant ◽

Mitochondrial Functions ◽

Brain Mitochondrial Function

Oxidative stress in the obese-insulin resistant condition has been shown to affect cognitive as well as brain mitochondrial functions. Garlic extract has exerted a potent antioxidant effect. However, the effects of garlic extract on the brain of obese-insulin resistant rats have never been investigated. We hypothesized that garlic extract improves cognitive function and brain mitochondrial function in obese-insulin resistant rats induced by long-term high-fat diet (HFD) consumption. Male Wistar rats were fed either normal diet or HFD for 16 weeks (n = 24/group). At week 12, rats in each dietary group received either vehicle or garlic extract (250 and 500 mg·kg–1·day–1) for 28 days. Learning and memory behaviors, metabolic parameters, and brain mitochondrial function were determined at the end of treatment. HFD led to increased body weight, visceral fat, plasma insulin, cholesterol, and malondialdehyde (MDA) levels, indicating the development of insulin resistance. Furthermore, HFD rats had cognitive deficit and brain mitochondrial dysfunction. HFD rats treated with both doses of garlic extract had decreased body weight, visceral fat, plasma cholesterol, and MDA levels. Garlic extract also improved cognitive function and brain mitochondrial function, which were impaired in obese-insulin resistant rats caused by HFD consumption.

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The leishmanicidal activity of artemisinin is mediated by cleavage of the endoperoxide bridge and mitochondrial dysfunction

Parasitology ◽

10.1017/s003118201800183x ◽

2018 ◽

Vol 146 (4) ◽

pp. 511-520 ◽

Cited By ~ 8

Author(s):

Sritama De Sarkar ◽

Deblina Sarkar ◽

Avijit Sarkar ◽

Aishwarya Dighal ◽

Sasanka Chakrabarti ◽

...

Keyword(s):

Mitochondrial Dysfunction ◽

Mitochondrial Membrane ◽

Therapeutic Strategy ◽

Atp Hydrolysis ◽

Underlying Mechanism ◽

Oxygen Species ◽

High Iron Content ◽

Mitochondrial Superoxide ◽

Transport Chain ◽

Anti Oxidant

AbstractEndoperoxides kill malaria parasitesviacleavage of their endoperoxide bridge by haem or iron, leading to generation of cytotoxic oxygen-centred radicals. In view of theLeishmaniaparasites having a relatively compromised anti-oxidant defense and high iron content, this study aims to establish the underlying mechanism(s) accounting for the apoptotic-like death ofLeishmaniapromastigotes by artemisinin, an endoperoxide. The formation of reactive oxygen species was confirmed by flow cytometry and was accompanied by inhibition of mitochondrial complexes I–III and II–III. However, this did not translate into a generation of mitochondrial superoxide or decrease in oxygen consumption, indicating minimal impairment of the electron transport chain. Artemisinin caused depolarization of the mitochondrial membrane along with a substantial depletion of adenosine triphosphatase (ATP), but it was not accompanied by enhancement of ATP hydrolysis. Collectively, the endoperoxide-mediated radical formation by artemisinin inLeishmaniapromastigotes was the key step for triggering its antileishmanial activity, leading secondarily to mitochondrial dysfunction indicating that endoperoxides represent a promising therapeutic strategy againstLeishmaniaworthy of pharmacological consideration.

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Impact of Silibinin A on Bioenergetics in PC12APPsw Cells and Mitochondrial Membrane Properties in Murine Brain Mitochondria

Antioxidants ◽

10.3390/antiox10101520 ◽

2021 ◽

Vol 10 (10) ◽

pp. 1520

Author(s):

Carsten Esselun ◽

Bastian Bruns ◽

Stephanie Hagl ◽

Rekha Grewal ◽

Gunter P. Eckert

Keyword(s):

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Mitochondrial Membrane ◽

Brain Mitochondria ◽

Membrane Properties ◽

Protective Effects ◽

Positive Effects ◽

Atp Levels ◽

Age Related ◽

Murine Brain

Introduction: Age-related multifactorial diseases, such as the neurodegenerative Alzheimer’s disease (AD), still remain a challenge to today’s society. One mechanism associated with AD and aging in general is mitochondrial dysfunction (MD). Increasing MD is suggested to trigger other pathological processes commonly associated with neurodegenerative diseases. Silibinin A (SIL) is the main bioactive compound of the Silymarin extract from the Mediterranean plant Silybum marianum (L.) (GAERTN/Compositae). It is readily available as a herbal drug and well established in the treatment of liver diseases as a potent radical scavenger reducing lipid peroxidation and stabilize membrane properties. Recent data suggest that SIL might also act on neurological changes related to MD. Methods: PC12APPsw cells produce low levels of human Aβ and thus act as a cellular model of early AD showing changed mitochondrial function. We investigated whether SIL could affect mitochondrial function by measuring ATP, MMP, as well as respiration, mitochondrial mass, cellular ROS and lactate/pyruvate concentrations. Furthermore, we investigated its effects on the mitochondrial membrane parameters of swelling and fluidity in mitochondria isolated from the brains of mice. Results: In PC12APPsw cells, SIL exhibits strong protective effects by rescuing MMP and ATP levels from SNP-induced mitochondrial damage and improving basal ATP levels. However, SIL did not affect mitochondrial respiration and mitochondrial content. SIL significantly reduced cellular ROS and pyruvate concentrations. Incubation of murine brain mitochondria with SIL significantly reduces Ca2+ induced swelling and improves membrane fluidity. Conclusions: Although OXPHOS activity was unaffected at this early stage of a developing mitochondrial dysfunction, SIL showed protective effects on MMP, ATP- after SNP-insult and ROS-levels in APPsw-transfected PC12 cells. Results from experiments with isolated mitochondria imply that positive effects possibly result from an interaction of SIL with mitochondrial membranes and/or its antioxidant activity. Thus, SIL might be a promising compound to improve cellular health when changes to mitochondrial function occur.

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Effect of hepatic sympathetic nerve removal on energy metabolism in an animal model of cognitive impairment and its relationship to Glut2 expression

Open Life Sciences ◽

10.1515/biol-2020-0033 ◽

2020 ◽

Vol 15 (1) ◽

pp. 311-317

Author(s):

Riming Wei ◽

Xiuhong Zhuge ◽

Pengpeng Yue ◽

Manjun Liu ◽

Lin Zhu ◽

...

Keyword(s):

Body Weight ◽

Cognitive Impairment ◽

Sympathetic Nerve ◽

Periodic Acid ◽

Liver Glycogen ◽

Underlying Mechanism ◽

Control Group ◽

Periodic Acid Schiff ◽

Pas Staining ◽

Experimental Group

AbstractThe aims of this study were to investigate the effect of hepatic sympathetic nerve removal on glucose and lipid metabolism in rats with cognitive impairment and to evaluate the relationship between these effects and liver Glut2 expression. Hippocampal injection of Aβ1–42 was used to induce cognitive impairment. Impaired rats were divided into experimental, sham, and control groups. The experimental group was injected with 6-hydroxydopamine to remove the sympathetic nerve. At 4 weeks post injection, body weight, food and water intake, blood sugar, and blood lipids were measured, and periodic acid-Schiff (PAS) staining was used to assess the liver glycogen content. Liver Glut2 mRNA and protein were also detected. The experimental group showed reduced body weight, food intake, and blood glucose levels and elevated insulin levels compared with the control group. PAS staining showed higher glycogen contents in the experimental group than in controls. The expression levels of Glut2 mRNA and protein in the experimental group were significantly lower than in the controls. Metabolism was significantly impacted in rats with cognitive impairment following removal of the hepatic sympathetic nerve. Disruption to Glut2 liver expression via sympathetic nerve disruption represents a possible underlying mechanism.

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miR-138-5p Inhibits Vascular Mimicry by Targeting the HIF-1α/VEGFA Pathway in Hepatocellular Carcinoma

10.21203/rs.3.rs-1080163/v1 ◽

2021 ◽

Author(s):

Hongwei Liu ◽

Xiujin Hu ◽

Weihe Tan ◽

Peng Zhou ◽

Yanmei Liu ◽

...

Keyword(s):

Hepatocellular Carcinoma ◽

Cancer Progression ◽

Periodic Acid ◽

Hypoxia Inducible Factor ◽

Underlying Mechanism ◽

Tube Formation ◽

Periodic Acid Schiff ◽

Vascular Mimicry ◽

Endothelial Growth Factor

Abstract Tumor vascular mimicry (VM) is the process of new blood vessels formed by tumor cells rather than endothelial cells. An increasing number of researches have revealed that VM process is associated with cancer progression and metastasis. miR-138-5p has been reported to act as a tumor suppressor in many cancers. However, the role and underlying mechanism of miR-138-5p in hepatocellular carcinoma (HCC) VM remain unclear. In this study, VM density was detected by CD31/periodic acid-Schiff double staining in HCC clinical specimens. We found that miR-138-5p expression correlated strongly negatively with microvessel density. Additionally, miR-138-5p mimic or inhibitor decreased or increased, respectively, tube formation capacity in HepG2 and Hep3B cells. Consistent with this, miR-138-5p repressed vessel density in vivo. Moreover, miR-138-5p targeted hypoxia-inducible factor 1α (HIF-1α) and regulated expression of HIF-1α and vascular endothelial growth factor A (VEGFA), which are established classical markers of angiogenesis. Consistent with these findings, the HIF-1α inhibitor CAY10585 effectively blocked HCC cell VM and VEGFA expression. In conclusion, miR-138-5p inhibits HepG2 and Hep3B cell VM by blocking the HIF-1α/VEGFA pathway. Therefore, miR-138-5p may serve as a useful therapeutic target for miRNA-based HCC therapy.

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Selenomethionine Improves Mitochondrial Function by Upregulating Mitochondrial Selenoprotein in a Model of Alzheimer’s Disease

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2021.750921 ◽

2021 ◽

Vol 13 ◽

Author(s):

Chen Chen ◽

Yao Chen ◽

Zhong-Hao Zhang ◽

Shi-Zheng Jia ◽

Yu-Bin Chen ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Membrane Potential ◽

Energy Metabolism ◽

Mitochondrial Dysfunction ◽

Mitochondrial Membrane Potential ◽

Neurofibrillary Tangles ◽

Mitochondrial Function ◽

Mitochondrial Membrane ◽

Amyloid Plaques

Alzheimer’s disease (AD), the most common neurodegenerative disease in elderly humans, is pathologically characterized by amyloid plaques and neurofibrillary tangles. Mitochondrial dysfunction that occurs in the early stages of AD, which includes dysfunction in mitochondrial generation and energy metabolism, is considered to be closely associated with AD pathology. Selenomethionine (Se-Met) has been reported to improve cognitive impairment and reduce amyloid plaques and neurofibrillary tangles in 3xTg-AD mice. Whether Se-Met can regulate mitochondrial dysfunction in an AD model during this process remains unknown.In this study, the N2a-APP695-Swedish (N2aSW) cell and 8-month-old 3xTg-AD mice were treated with Se-Met in vitro and in vivo. Our study showed that the numbers of mitochondria were increased after treatment with Se-Met. Se-Met treatment also significantly increased the levels of NRF1 and Mfn2, and decreased those of OPA1 and Drp1. In addition, the mitochondrial membrane potential was significantly increased, while the ROS levels and apoptosis rate were significantly decreased, in cells after treatment with Se-Met. The levels of ATP, complex IV, and Cyt c and the activity of complex V were all significantly increased. Furthermore, the expression level of SELENO O was increased after Se-Met treatment. Thus, Se-Met can maintain mitochondrial dynamic balance, promote mitochondrial fusion or division, restore mitochondrial membrane potential, promote mitochondrial energy metabolism, inhibit intracellular ROS generation, and reduce apoptosis. These effects are most likely mediated via upregulation of SELENO O. In summary, Se-Met improves mitochondrial function by upregulating mitochondrial selenoprotein in these AD models.

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Gut microbiota is essential in PGRP-LA regulated immune protection against Plasmodium berghei infection

Parasites & Vectors ◽

10.1186/s13071-019-3876-y ◽

2020 ◽

Vol 13 (1) ◽

Cited By ~ 3

Author(s):

Li Gao ◽

Xiumei Song ◽

Jingwen Wang

Keyword(s):

Gut Microbiota ◽

Structural Integrity ◽

Periodic Acid ◽

Expression Patterns ◽

Underlying Mechanism ◽

Parasite Infection ◽

Immune Defense ◽

Periodic Acid Schiff ◽

Immune Genes ◽

Pas Staining

Abstract Background Malaria remains to be one of the deadliest infectious diseases and imposes substantial financial and social costs in the world. Mosquitoes rely on the immune system to control parasite infection. Peptidoglycan recognition proteins (PGRPs), a family of pattern-recognition receptors (PRR), are responsible for initiating and regulating immune signaling pathways. PGRP-LA is involved in the regulation of immune defense against the Plasmodium parasite, however, the underlying mechanism needs to be further elucidated. Methods The spatial and temporal expression patterns of pgrp-la in Anopheles stephensi were analyzed by qPCR. The function of PGRP-LA was examined using a dsRNA-based RNA interference strategy. Western blot and periodic acid schiff (PAS) staining were used to assess the structural integrity of peritrophic matrix (PM). Results The expression of pgrp-la in An. stephensi was induced in the midgut in response to the rapid proliferating gut microbiota post-blood meal. Knocking down of pgrp-la led to the downregulation of immune effectors that control gut microbiota growth. The decreased expression of these immune genes also facilitated P. berghei infection. However, such dsLA treatment did not influence the structural integrity of PM. When gut microbiota was removed by antibiotic treatment, the regulation of PGRP-LA on immune effectors was abolished and the knock down of pgrp-la failed to increase susceptibility of mosquitoes to parasite infection. Conclusions PGRP-LA regulates the immune responses by sensing the dynamics of gut microbiota. A mutual interaction between gut microbiota and PGRP-LA contributes to the immune defense against Plasmodium parasites in An. stephensi.

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Endoplasmic Reticulum Associated Degradation (ERAD) Deficiency Promotes Mitochondrial Dysfunction and Transcriptional Rewiring in Human Hepatic Cells

10.1101/2020.04.22.053546 ◽

2020 ◽

Author(s):

Xiaoqing Yang ◽

Qingqing Liu ◽

Guangyu Long ◽

Yabin Hu ◽

Zhenglong Gu ◽

...

Keyword(s):

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Mammalian Cells ◽

Structural Integrity ◽

Protein Quality ◽

Critical Role ◽

Mitochondrial Outer Membrane ◽

Genetic Ablation ◽

Mitochondrial Functions ◽

Quality Control Process

AbstractMitochondrial dysfunction has been associated with a variety of human diseases including neurodegeneration, diabetes, non-alcohol fatty liver disease (NAFLD) and cancer, but its underlying causes are incompletely understood. Endoplasmic reticular associated degradation (ERAD) is a protein quality control process essential for maintaining ER homeostasis. Using the human hepatic cell line HepG2 as a model, we show here that ERAD is critically required for mitochondrial function in mammalian cells. Pharmacological inhibition or genetic ablation of ERAD increases cell death under both basal conditions and in response to proinflammatory cytokines. Decreased viability of ERAD-deficient HepG2 cells was traced to impaired mitochondrial functions including reduced ATP production, enhanced reactive oxygen species (ROS) accumulation and increased mitochondrial outer membrane permeability (MOMP). Transcriptome profiling reveals widespread down-regulation in the expression of genes underpinning mitochondrial functions, and up-regulation in the genes with association to tumor growth and aggression. These results highlight a critical role for ERAD in maintaining mitochondrial functional and structural integrity and raise the possibility to improve cellular and organismal mitochondrial function via enhancing cellular ERAD capacity.

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ERAD deficiency promotes mitochondrial dysfunction and transcriptional rewiring in human hepatic cells

Journal of Biological Chemistry ◽

10.1074/jbc.ra120.013987 ◽

2020 ◽

Vol 295 (49) ◽

pp. 16743-16753

Author(s):

Qingqing Liu ◽

Xiaoqin Yang ◽

Guangyu Long ◽

Yabing Hu ◽

Zhenglong Gu ◽

...

Keyword(s):

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Mammalian Cells ◽

Structural Integrity ◽

Protein Quality ◽

Critical Role ◽

Mitochondrial Outer Membrane ◽

Genetic Ablation ◽

Mitochondrial Functions ◽

Quality Control Process

Mitochondrial dysfunction is associated with a variety of human diseases including neurodegeneration, diabetes, nonalcohol fatty liver disease (NAFLD), and cancer, but its underlying causes are incompletely understood. Using the human hepatic cell line HepG2 as a model, we show here that endoplasmic reticulum-associated degradation (ERAD), an ER protein quality control process, is critically required for mitochondrial function in mammalian cells. Pharmacological inhibition or genetic ablation of key proteins involved in ERAD increased cell death under both basal conditions and in response to proinflammatory cytokines, a situation frequently found in NAFLD. Decreased viability of ERAD-deficient HepG2 cells was traced to impaired mitochondrial functions including reduced ATP production, enhanced reactive oxygen species (ROS) accumulation, and increased mitochondrial outer membrane permeability. Transcriptome profiling revealed widespread down-regulation of genes underpinning mitochondrial functions, and up-regulation of genes associated with tumor growth and aggression. These results highlight a critical role for ERAD in maintaining mitochondrial functional and structural integrity and raise the possibility of improving cellular and organismal mitochondrial function via enhancing cellular ERAD capacity.

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