scholarly journals Elevated Lactate by High-Intensity Interval Training Regulates the Hippocampal BDNF Expression and the Mitochondrial Quality Control System

2021 ◽  
Vol 12 ◽  
Author(s):  
Jingyun Hu ◽  
Ming Cai ◽  
Qinghui Shang ◽  
Zhaorun Li ◽  
Yu Feng ◽  
...  
Keyword(s):  
Quality Control ◽  
Control System ◽  
Mitochondrial Function ◽  
Interval Training ◽  
Quality Control System ◽  
Bdnf Expression ◽  
Mitochondrial Quality Control ◽  
High Intensity Interval

High-intensity interval training (HIIT) is reported to be beneficial to brain-derived neurotrophic factor (BDNF) biosynthesis. A key element in this may be the existence of lactate, the most obvious metabolic product of exercise. In vivo, this study investigated the effects of a 6-week HIIT on the peripheral and central lactate changes, mitochondrial quality control system, mitochondrial function and BDNF expression in mouse hippocampus. In vitro, primary cultured mice hippocampal cells were used to investigate the role and the underlying mechanisms of lactate in promoting mitochondrial function during HIIT. In vivo studies, we firstly reported that HIIT can potentiate mitochondrial function [boost some of the mitochondrial oxidative phosphorylation (OXPHOS) genes expression and ATP production], stimulate BDNF expression in mouse hippocampus along with regulating the mitochondrial quality control system in terms of promoting mitochondrial fusion and biogenesis, and suppressing mitochondrial fission. In parallel to this, the peripheral and central lactate levels elevated immediately after the training. In vitro study, our results revealed that lactate was in charge of regulating mitochondrial quality control system for mitochondrial function and thus may contribute to BDNF expression. In conclusion, our study provided the mitochondrial mechanisms of HIIT enhancing brain function, and that lactate itself can mediate the HIIT effect on mitochondrial quality control system in the hippocampus.

scholarly journals Insertion Defects of Mitochondrially Encoded Proteins Burden the Mitochondrial Quality Control System

Cells ◽  
2018 ◽  
Vol 7 (10) ◽  
pp. 172 ◽  
Author(s):  
Braulio Vargas Möller-Hergt ◽  
Andreas Carlström ◽  
Tamara Suhm ◽  
Martin Ott
Keyword(s):  
Quality Control ◽  
Control System ◽  
Mitochondrial Protein ◽  
Quality Control System ◽  
Yeast Cells ◽  
Mitochondrial Quality Control ◽  
Protein Insertion ◽  
Mitochondrial Proteome ◽  
Proteotoxic Stress ◽  
Membrane Protein Insertion

The mitochondrial proteome contains proteins from two different genetic systems. Proteins are either synthesized in the cytosol and imported into the different compartments of the organelle or directly produced in the mitochondrial matrix. To ensure proteostasis, proteins are monitored by the mitochondrial quality control system, which will degrade non-native polypeptides. Defective mitochondrial membrane proteins are degraded by membrane-bound AAA-proteases. These proteases are regulated by factors promoting protein turnover or preventing their degradation. Here we determined genetic interactions between the mitoribosome receptors Mrx15 and Mba1 with the quality control system. We show that simultaneous absence of Mrx15 and the regulators of the i-AAA protease Mgr1 and Mgr3 provokes respiratory deficiency. Surprisingly, mutants lacking Mrx15 were more tolerant against proteotoxic stress. Furthermore, yeast cells became hypersensitive against proteotoxic stress upon deletion of MBA1. Contrary to Mrx15, Mba1 cooperates with the regulators of the m-AAA and i-AAA proteases. Taken together, these results suggest that membrane protein insertion and mitochondrial AAA-proteases are functionally coupled, possibly reflecting an early quality control step during mitochondrial protein synthesis.

scholarly journals Endotoxin Engages Mitochondrial Quality Control via an iNOS-Reactive Oxygen Species Signaling Pathway in Hepatocytes

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Anthony Cyr ◽  
Lauran Chambers ◽  
Paul K. Waltz ◽  
Sean P. Whelan ◽  
Lauryn Kohut ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Reactive Oxygen Species ◽  
Quality Control ◽  
Mitochondrial Biogenesis ◽  
Organ Injury ◽  
Oxygen Species ◽  
Wild Type ◽  
Mitochondrial Quality Control

Background. Organ injury and dysfunction in sepsis accounts for significant morbidity and mortality. Adaptive cellular responses in the setting of sepsis prevent injury and allow for organ recovery. We and others have shown that part of the adaptive response includes regulation of cellular respiration and maintenance of a healthy mitochondrial population. Herein, we hypothesized that endotoxin-induced changes in hepatocyte mitochondrial respiration and homeostasis are regulated by an inducible nitric oxide synthase/nitric oxide (iNOS/NO)-mitochondrial reactive oxygen species (mtROS) signaling axis, involving activation of the NRF2 signaling pathway. Methods. Wild-type (C57Bl/6) or iNos-/- male mice were subjected to intraperitoneal lipopolysaccharide (LPS) injections to simulate endotoxemia. Individual mice were randomized to treatment with NO-releasing agent DPTA-NONOate, mtROS scavenger MitoTEMPO, or vehicle controls. Other mice were treated with scramble or Nrf2-specific siRNA via tail vein injection. Primary murine hepatocytes were utilized for in vitro studies with or without LPS stimulation. Oxygen consumption rates were measured to establish mitochondrial respiratory parameters. Western blotting, confocal microscopy with immunocytochemistry, and rtPCR were performed for analysis of iNOS as well as markers of both autophagy and mitochondrial biogenesis. Results. LPS treatment inhibited aerobic respiration in vitro in wild-type but not iNos-/- cells. Experimental endotoxemia in vivo or in vitro induced iNOS protein and mtROS production. However, induction of mtROS was dependent on iNOS expression. Furthermore, LPS-induced hepatic autophagy/mitophagy and mitochondrial biogenesis were significantly attenuated in iNos-/- mice or cells with NO or mtROS scavenging. These responses were rescued in iNos-/- mice via delivery of NO both in vivo and in vitro. Conclusions. These data suggest that regulation of mitochondrial quality control following hepatocyte LPS exposure is dependent at least in part on a NO-mtROS signaling network. Further investigation to identify specific agents that modulate this process may facilitate the prevention of organ injury in sepsis.

scholarly journals Mitochondria Homeostasis and Oxidant/Antioxidant Balance in Skeletal Muscle—Do Myokines Play a Role?

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 179
Author(s):  
Brian Pak Shing Pang ◽  
Wing Suen Chan ◽  
Chi Bun Chan
Keyword(s):  
Skeletal Muscle ◽  
Quality Control ◽  
Control System ◽  
Energy Content ◽  
Mitochondrial Dynamics ◽  
Critical Role ◽  
Oxidative Capacity ◽  
Quality Control System ◽  
Mitochondrial Quality Control ◽  
Tissue Mass

Mitochondria are the cellular powerhouses that generate adenosine triphosphate (ATP) to substantiate various biochemical activities. Instead of being a static intracellular structure, they are dynamic organelles that perform constant structural and functional remodeling in response to different metabolic stresses. In situations that require a high ATP supply, new mitochondria are assembled (mitochondrial biogenesis) or formed by fusing the existing mitochondria (mitochondrial fusion) to maximize the oxidative capacity. On the other hand, nutrient overload may produce detrimental metabolites such as reactive oxidative species (ROS) that wreck the organelle, leading to the split of damaged mitochondria (mitofission) for clearance (mitophagy). These vital processes are tightly regulated by a sophisticated quality control system involving energy sensing, intracellular membrane interaction, autophagy, and proteasomal degradation to optimize the number of healthy mitochondria. The effective mitochondrial surveillance is particularly important to skeletal muscle fitness because of its large tissue mass as well as its high metabolic activities for supporting the intensive myofiber contractility. Indeed, the failure of the mitochondrial quality control system in skeletal muscle is associated with diseases such as insulin resistance, aging, and muscle wasting. While the mitochondrial dynamics in cells are believed to be intrinsically controlled by the energy content and nutrient availability, other upstream regulators such as hormonal signals from distal organs or factors generated by the muscle itself may also play a critical role. It is now clear that skeletal muscle actively participates in systemic energy homeostasis via producing hundreds of myokines. Acting either as autocrine/paracrine or circulating hormones to crosstalk with other organs, these secretory myokines regulate a large number of physiological activities including insulin sensitivity, fuel utilization, cell differentiation, and appetite behavior. In this article, we will review the mechanism of myokines in mitochondrial quality control and ROS balance, and discuss their translational potential.

scholarly journals KCa3.1 Mediates Dysregulation of Mitochondrial Quality Control in Diabetic Kidney Disease

2021 ◽  
Vol 9 ◽  
Author(s):  
Chunling Huang ◽  
Hao Yi ◽  
Ying Shi ◽  
Qinghua Cao ◽  
Yin Shi ◽  
...  
Keyword(s):  
Quality Control ◽  
Kidney Disease ◽  
Diabetic Kidney Disease ◽  
Diabetic Mice ◽  
Mitochondrial Quality Control ◽  
Diabetic Kidney ◽  
Hk2 Cells ◽  
Tgf Β1

Mitochondrial dysfunction is implicated in the pathogenesis of diabetic kidney disease. Mitochondrial quality control is primarily mediated by mitochondrial turnover and repair through mitochondrial fission/fusion and mitophagy. We have previously shown that blockade of the calcium-activated potassium channel KCa3.1 ameliorates diabetic renal fibrosis. However, the mechanistic link between KCa3.1 and mitochondrial quality control in diabetic kidney disease is not yet known. Transforming growth factor β1 (TGF-β1) plays a central role in diabetic kidney disease. Recent studies indicate an emerging role of TGF-β1 in the regulation of mitochondrial function. However, the molecular mechanism mediating mitochondrial quality control in response to TGF-β1 remains limited. In this study, mitochondrial function was assessed in TGF-β1-exposed renal proximal tubular epithelial cells (HK2 cells) transfected with scrambled siRNA or KCa3.1 siRNA. In vivo, diabetes was induced in KCa3.1+/+ and KCa3.1−/− mice by low-dose streptozotocin (STZ) injection. Mitochondrial fission/fusion-related proteins and mitophagy markers, as well as BCL2 interacting protein 3 (BNIP3) (a mitophagy regulator) were examined in HK2 cells and diabetic mice kidneys. The in vitro results showed that TGF-β1 significantly inhibited mitochondrial ATP production rate and increased mitochondrial ROS (mtROS) production when compared to control, which was normalized by KCa3.1 gene silencing. Increased fission and suppressed fusion were found in both TGF-β1-treated HK2 cells and diabetic mice, which were reversed by KCa3.1 deficiency. Furthermore, our results showed that mitophagy was inhibited in both in vitro and in vivo models of diabetic kidney disease. KCa3.1 deficiency restored abnormal mitophagy by inhibiting BNIP3 expression in TGF-β1-induced HK2 cells as well as in the diabetic mice. Collectively, these results indicate that KCa3.1 mediates the dysregulation of mitochondrial quality control in diabetic kidney disease.

scholarly journals Different dynamic movements of wild-type and pathogenic VCPs and their cofactors to damaged mitochondria in a Parkin-mediated mitochondrial quality control system

2013 ◽  
Vol 18 (12) ◽  
pp. 1131-1143 ◽  
Author(s):  
Yoko Kimura ◽  
Junpei Fukushi ◽  
Seiji Hori ◽  
Noriyuki Matsuda ◽  
Kei Okatsu ◽  
...  
Keyword(s):  
Quality Control ◽  
Control System ◽  
Quality Control System ◽  
Wild Type ◽  
Mitochondrial Quality Control

scholarly journals Overexpression of human BAG3P209L in mice causes restrictive cardiomyopathy

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kenichi Kimura ◽  
Astrid Ooms ◽  
Kathrin Graf-Riesen ◽  
Maithreyan Kuppusamy ◽  
Andreas Unger ◽  
...  
Keyword(s):  
Quality Control ◽  
Control System ◽  
Protein Quality ◽  
Protein Quality Control ◽  
Restrictive Cardiomyopathy ◽  
Quality Control System ◽  
Rna Seq ◽  
Protein Quality Control System ◽  
Acid Exchange

AbstractAn amino acid exchange (P209L) in the HSPB8 binding site of the human co-chaperone BAG3 gives rise to severe childhood cardiomyopathy. To phenocopy the disease in mice and gain insight into its mechanisms, we generated humanized transgenic mouse models. Expression of human BAG3P209L-eGFP in mice caused Z-disc disintegration and formation of protein aggregates. This was accompanied by massive fibrosis resulting in early-onset restrictive cardiomyopathy with increased mortality as observed in patients. RNA-Seq and proteomics revealed changes in the protein quality control system and increased autophagy in hearts from hBAG3P209L-eGFP mice. The mutation renders hBAG3P209L less soluble in vivo and induces protein aggregation, but does not abrogate hBAG3 binding properties. In conclusion, we report a mouse model mimicking the human disease. Our data suggest that the disease mechanism is due to accumulation of hBAG3P209L and mouse Bag3, causing sequestering of components of the protein quality control system and autophagy machinery leading to sarcomere disruption.

Sign in / Sign up

Export Citation Format

Share Document