Mitochondrial Dysfunction as a Novel Target for Neuroprotective Nutraceuticals in Ocular Diseases

The eyes require a rich oxygen and nutrient supply; hence, the high-energy demand of the visual system makes it sensitive to oxidative stress. Excessive free radicals result in mitochondrial dysfunction and lead to retinal neurodegeneration, as an early stage of retinal metabolic disorders. Retinal cells are vulnerable because of their coordinated interaction and intricate neural networks. Nutraceuticals are believed to target multiple pathways and have shown neuroprotective benefits by scavenging free radicals and promoting mitochondrial gene expression. Furthermore, encouraging results demonstrate that nutraceuticals improve the organization of retinal cells and visual functions. This review discusses the mitochondrial impairments of retinal cells and the mechanisms underlying the neuroprotective effects of nutraceuticals. However, some unsolved problems still exist between laboratory study and clinical therapy. Poor bioavailability and bioaccessibility strongly limit their development. A new delivery system and improved formulation may offer promise for health care applications.

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ATM is activated by ATP depletion and modulates mitochondrial function through NRF1

10.1101/414490 ◽

2018 ◽

Author(s):

Hei-Man Chow ◽

Aifang Cheng ◽

Xuan Song ◽

Mavis R. Swerdel ◽

Ronald P. Hart ◽

...

Keyword(s):

Purkinje Cells ◽

Mitochondrial Function ◽

Energy Demand ◽

Nuclear Translocation ◽

Physiological Activity ◽

Mitochondrial Gene ◽

High Energy ◽

Atp Depletion ◽

Nuclear Respiratory Factor ◽

Atp Levels

AbstractWe have uncovered new insights into the symptoms of ataxia-telangiectasia (A-T). Neurons with high physiological activity, particularly cerebellar Purkinje cells, have large and dynamic ATP demands. Depletion of ATP generates reactive oxygen species that activate ATM (the A-T Mutated gene product). Activated in this way, but not by DNA damage, ATM phosphorylates nuclear respiratory factor-1 (NRF1). This leads to NRF1 dimerization, nuclear translocation and the upregulation of nuclear-encoded mitochondrial genes, thus enhancing the capacity of the electron transport chain (ETC) and restoring mitochondrial function. In cells with ATM deficiency, resting ATP levels are normal, but cells replenish ATP poorly following surges in energy demand and chronic ATP insufficiency endangers cell survival. This is a particular problem for energy-intensive cells such as Purkinje cells, which degenerate in A-T. Our findings thus identify ATM as a guardian of mitochondrial output as well as genomic integrity, and suggest that alternate fuel sources may ameliorate A-T disease symptoms.SummaryOxidative stress, resulting from neuronal activity and depleted ATP levels, activates ATM, which phosphorylates NRF1, causing nuclear translocation and upregulation of mitochondrial gene expression. In ATM deficiency, ATP levels recover more slowly, particularly in active neurons with high energy demands.

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Mitochondrial DNA mutations in renal disease: an overview

Pediatric Nephrology ◽

10.1007/s00467-019-04404-6 ◽

2020 ◽

Vol 36 (1) ◽

pp. 9-17 ◽

Cited By ~ 1

Author(s):

Larissa P. Govers ◽

Hakan R. Toka ◽

Ali Hariri ◽

Stephen B. Walsh ◽

Detlef Bockenhauer

Keyword(s):

Renal Disease ◽

Mitochondrial Dysfunction ◽

Energy Demand ◽

Nuclear Dna ◽

Symptom Relief ◽

High Energy ◽

Glomerular Sclerosis ◽

Renal Fanconi Syndrome ◽

Mitochondrial Cytopathies ◽

Focal Segmental Glomerular Sclerosis

AbstractKidneys have a high energy demand to facilitate the reabsorption of the glomerular filtrate. For this reason, renal cells have a high density of mitochondria. Mitochondrial cytopathies can be the result of a mutation in both mitochondrial and nuclear DNA. Mitochondrial dysfunction can lead to a variety of renal manifestations. Examples of tubular manifestations are renal Fanconi Syndrome, which is often found in patients diagnosed with Kearns-Sayre and Pearson’s marrow-pancreas syndrome, and distal tubulopathies, which result in electrolyte disturbances such as hypomagnesemia. Nephrotic syndrome can be a glomerular manifestation of mitochondrial dysfunction and is typically associated with focal segmental glomerular sclerosis on histology. Tubulointerstitial nephritis can also be seen in mitochondrial cytopathies and may lead to end-stage renal disease. The underlying mechanisms of these cytopathies remain incompletely understood; therefore, current therapies focus mainly on symptom relief. A better understanding of the molecular disease mechanisms is critical in order to improve treatments.

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Neuroprotective Effects of Tempol, a Catalytic Scavenger of Peroxynitrite-Derived Free Radicals, in a Mouse Traumatic Brain Injury Model

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2008.10 ◽

2008 ◽

Vol 28 (6) ◽

pp. 1114-1126 ◽

Cited By ~ 94

Author(s):

Ying Deng-Bryant ◽

Indrapal N Singh ◽

Kimberly M Carrico ◽

Edward D Hall

Keyword(s):

Traumatic Brain Injury ◽

Free Radicals ◽

Brain Injury ◽

Oxidative Damage ◽

Mitochondrial Dysfunction ◽

Neuroprotective Effect ◽

Complete Suppression ◽

Post Injury ◽

Multiple Dosing ◽

Neuroprotective Effects

We examined the ability of tempol, a catalytic scavenger of peroxynitrite (PN)-derived free radicals, to reduce cortical oxidative damage, mitochondrial dysfunction, calpain-mediated cytoskeletal (α-spectrin) degradation, and neurodegeneration, and to improve behavioral recovery after a severe (depth 1.0 mm), unilateral controlled cortical impact traumatic brain injury (CCI-TBI) in male CF-1 mice. Administration of a single 300 mg/kg intraperitoneal dose of tempol 15 mins after TBI produced a complete suppression of PN-mediated oxidative damage (3-nitrotyrosine, 3NT) in injured cortical tissue at 1 h after injury. Identical tempol dosing maintained respiratory function and attenuated 3NT in isolated cortical mitochondria at 12 h after injury, the peak of mitochondrial dysfunction. Multiple dosing with tempol (300 mg/kg intraperitoneally at 15 mins, 3, 6, 9, and 12 h) also suppressed α-spectrin degradation by 45% at its 24 h post-injury peak. The same dosing regimen improved 48 h motor function and produced a significant, but limited (17.4%, P<0.05), decrease in hemispheric neurodegeneration at 7 days. These results are consistent with a mechanistic link between PN-mediated oxidative damage to brain mitochondria, calpain-mediated proteolytic damage, and neurodegeneration. However, the modest neuroprotective effect of tempol suggests that multitarget combination strategies may be needed to interfere with posttraumatic secondary injury to a degree worthy of clinical translation.

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Genetic Neuropathy Due to Impairments in Mitochondrial Dynamics

Biology ◽

10.3390/biology10040268 ◽

2021 ◽

Vol 10 (4) ◽

pp. 268

Author(s):

Govinda Sharma ◽

Gerald Pfeffer ◽

Timothy E. Shutt

Keyword(s):

Peripheral Neuropathy ◽

Mitochondrial Dysfunction ◽

Energy Demand ◽

Mitochondrial Dynamics ◽

High Energy ◽

Morphological Properties ◽

Peripheral Neurons ◽

Pathogenic Variants ◽

Mitochondrial Motility ◽

Prevailing View

Mitochondria are dynamic organelles capable of fusing, dividing, and moving about the cell. These properties are especially important in neurons, which in addition to high energy demand, have unique morphological properties with long axons. Notably, mitochondrial dysfunction causes a variety of neurological disorders including peripheral neuropathy, which is linked to impaired mitochondrial dynamics. Nonetheless, exactly why peripheral neurons are especially sensitive to impaired mitochondrial dynamics remains somewhat enigmatic. Although the prevailing view is that longer peripheral nerves are more sensitive to the loss of mitochondrial motility, this explanation is insufficient. Here, we review pathogenic variants in proteins mediating mitochondrial fusion, fission and transport that cause peripheral neuropathy. In addition to highlighting other dynamic processes that are impacted in peripheral neuropathies, we focus on impaired mitochondrial quality control as a potential unifying theme for why mitochondrial dysfunction and impairments in mitochondrial dynamics in particular cause peripheral neuropathy.

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Changes in lipid peroxidation during pregnancy and after delivery in rats: effect of pinealectomy

Reproduction ◽

10.1530/reprod/119.1.143 ◽

2000 ◽

pp. 143-149 ◽

Cited By ~ 9

Author(s):

RM Sainz ◽

RJ Reiter ◽

JC Mayo ◽

J Cabrera ◽

DX Tan ◽

...

Keyword(s):

Oxidative Stress ◽

Lipid Peroxidation ◽

Oxidative Damage ◽

Energy Demand ◽

Physiological State ◽

High Energy ◽

Free Radical Scavengers ◽

Radical Scavengers ◽

Oxygen Requirement ◽

Pregnant Rats

Pregnancy is a physiological state accompanied by a high energy demand of many bodily functions and an increased oxygen requirement. Because of the increased intake and utilization of oxygen, increased levels of oxidative stress would be expected. In the present study, the degree of lipid peroxidation was examined in different tissues from non-pregnant and pregnant rats after the delivery of their young. Melatonin and other indole metabolites are known to be direct free radical scavengers and indirect antioxidants. Thus the effect of pinealectomy at 1 month before pregnancy on the accumulation of lipid damage was investigated in non-pregnant and pregnant rats after the delivery of their young. Malonaldehyde and 4-hydroxyalkenal concentrations were measured in the lung, uterus, liver, brain, kidney, thymus and spleen from intact and pinealectomized pregnant rats soon after birth of their young and at 14 and 21 days after delivery. The same parameters were also evaluated in intact and pinealectomized non-pregnant rats. Shortly after delivery, lipid oxidative damage was increased in lung, uterus, brain, kidney and thymus of the mothers. No differences were detected in liver and spleen. Pinealectomy enhanced this effect in the uterus and lung. It is concluded that during pregnancy high levels of oxidative stress induce an increase in oxidative damage to lipids, which in some cases is inhibited by the antioxidative actions of pineal indoles.

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Biological and Phytochemical Screening of Fumaria indica extract on Chemically Induced Hepatocellular Carcinoma with Reference to Biochemical Parameters

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.10.2.1 ◽

2019 ◽

Vol 10 (02) ◽

Author(s):

Irfan Aziz ◽

Birendra Shrivastava ◽

Chandana Venkateswara Rao2 ◽

Sadath Ali

Keyword(s):

Free Radicals ◽

Liver Disease ◽

Liver Cancer ◽

Early Stage ◽

Food Additives ◽

Ethanolic Extract ◽

Hepatoprotective Activity ◽

Control Group ◽

Industrial Chemicals ◽

Toxic Industrial Chemicals

Liver disease or liver cancer is the sixth most common cancer and the third leading cause of cancer mortality in the world. Hepatitis viral infection, food additives, alcohol, fungal toxins (aflatoxins), toxic industrial chemicals, air and water pollutants are the major risk factors of liver cancer. Moreover, due to high tolerance of liver, HCC is seldom detected at an early stage and once detected treatment faces a poor prognosis in most cases.Fumaria indica possesses hepatoprotective activity as evidenced by the significant and dose dependent restoring the activities of entire liver cancer marker enzymes, diminution in tumor incidence, decrease in lipid peroxidation (LPO) and increase in the level of antioxidant enzymes (GSH, CAT, SOD, GPx and GST) through scavenging of free radicals, or by enhancing the activity of antioxidant, which then detoxify free radicals. These factors protect cells from ROS damage in NDEA and CCl4-induced hepatocarcinogenesis. Histopathological observations of liver tissues too correlated with the biochemical observations. Thus, present investigation suggested that the Fumaria indica would exert a chemoprotective effect by reversing the oxidant-antioxidant imbalance during hepatocarcinogenesis induced by NDEA and CCl4. Besides Fumaria indicais very much effective in preventing NDEA-induced multistage hepatocarcinogenesis possibly through antioxidant and antigenotoxic nature, which was confirmed by various liver injury and biochemical tumour markers enzymes. The hepatoprotective activity of a Fumaria indicaof 50 % ethanolic extract was studied using rats. The animals received a single intraperitoneal injection of N-nitrosodiethylamine 200mg/kg body wt followed by subcutaneous injection of CCl4 in a dose of 3 ml/kg body wt. Fumaria indica extract dose dependently and significantly the increase in serum hepatic enzyme levels after NDEAand CCl4 treatment compared to the toxin control group. The results of this study confirmed the antioxidant and hepatoprotective activity of the Fumaria indicaextract against carbon tetrachlorideand N-nitrosodiethylamine induced hepatotoxicity in rats. In addition to this, studies on molecular aspect of hepatoprotective therapy will give mechanistic information in hepatoprotective therapy and also critical balance should be there between the animal model and clinical research. The hepatoprotective properties of Fumaria indicashould provide useful information in the possible application in hepatic liver disease.

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The Quorum Sensing Auto-Inducer 2 (AI-2) Stimulates Nitrogen Fixation and Favors Ethanol Production over Biomass Accumulation in Zymomonas mobilis

International Journal of Molecular Sciences ◽

10.3390/ijms22115628 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5628

Author(s):

Valquíria Campos Alencar ◽

Juliana de Fátima dos Santos Silva ◽

Renata Ozelami Vilas Boas ◽

Vinícius Manganaro Farnézio ◽

Yara N. L. F. de Maria ◽

...

Keyword(s):

Nitrogen Fixation ◽

Quorum Sensing ◽

Ethanol Production ◽

N2 Fixation ◽

Energy Demand ◽

Zymomonas Mobilis ◽

Biomass Accumulation ◽

High Energy ◽

Gram Negative ◽

Expression Of Genes

Autoinducer 2 (or AI-2) is one of the molecules used by bacteria to trigger the Quorum Sensing (QS) response, which activates expression of genes involved in a series of alternative mechanisms, when cells reach high population densities (including bioluminescence, motility, biofilm formation, stress resistance, and production of public goods, or pathogenicity factors, among others). Contrary to most autoinducers, AI-2 can induce QS responses in both Gram-negative and Gram-positive bacteria, and has been suggested to constitute a trans-specific system of bacterial communication, capable of affecting even bacteria that cannot produce this autoinducer. In this work, we demonstrate that the ethanologenic Gram-negative bacterium Zymomonas mobilis (a non-AI-2 producer) responds to exogenous AI-2 by modulating expression of genes involved in mechanisms typically associated with QS in other bacteria, such as motility, DNA repair, and nitrogen fixation. Interestingly, the metabolism of AI-2-induced Z. mobilis cells seems to favor ethanol production over biomass accumulation, probably as an adaptation to the high-energy demand of N2 fixation. This opens the possibility of employing AI-2 during the industrial production of second-generation ethanol, as a way to boost N2 fixation by these bacteria, which could reduce costs associated with the use of nitrogen-based fertilizers, without compromising ethanol production in industrial plants.

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IoT Platform for Energy Sustainability in University Campuses

Sensors ◽

10.3390/s21020357 ◽

2021 ◽

Vol 21 (2) ◽

pp. 357

Author(s):

Pedro Moura ◽

José Ignacio Moreno ◽

Gregorio López López ◽

Manuel Alvarez-Campana

Keyword(s):

Energy Demand ◽

New Technologies ◽

Low Cost ◽

Sustainable Use ◽

High Energy ◽

Appropriate Technology ◽

Monitoring And Control ◽

Energy Sustainability ◽

University Campuses ◽

Iot Platform

University campuses are normally constituted of large buildings responsible for high energy demand, and are also important as demonstration sites for new technologies and systems. This paper presents the results of achieving energy sustainability in a testbed composed of a set of four buildings that constitute the Telecommunications Engineering School of the Universidad Politécnica de Madrid. In the paper, after characterizing the consumption of university buildings for a complete year, different options to achieve more sustainable use of energy are presented, considering the integration of renewable generation sources, namely photovoltaic generation, and monitoring and controlling electricity demand. To ensure the implementation of the desired monitoring and control, an internet of things (IoT) platform based on wireless sensor network (WSN) infrastructure was designed and installed. Such a platform supports a smart system to control the heating, ventilation, and air conditioning (HVAC) and lighting systems in buildings. Furthermore, the paper presents the developed IoT-based platform, as well as the implemented services. As a result, the paper illustrates how providing old existing buildings with the appropriate technology can contribute to the objective of transforming such buildings into nearly zero-energy buildings (nZEB) at a low cost.

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One Week of CDAHFD Induces Steatohepatitis and Mitochondrial Dysfunction with Oxidative Stress in Liver

International Journal of Molecular Sciences ◽

10.3390/ijms22115851 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5851

Author(s):

Takehito Sugasawa ◽

Seiko Ono ◽

Masato Yonamine ◽

Shin-ichiro Fujita ◽

Yuki Matsumoto ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

High Fat Diet ◽

Early Stage ◽

Droplet Deposition ◽

Nonalcoholic Fatty Liver ◽

Stress Markers ◽

Mitochondrial Dna Copy Number ◽

Short Period ◽

And Oxidative Stress

The prevalence of nonalcoholic fatty liver disease (NAFLD) has been rapidly increasing worldwide. A choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) has been used to create a mouse model of nonalcoholic steatohepatitis (NASH). There are some reports on the effects on mice of being fed a CDAHFD for long periods of 1 to 3 months. However, the effect of this diet over a short period is unknown. Therefore, we examined the effect of 1-week CDAHFD feeding on the mouse liver. Feeding a CDAHFD diet for only 1-week induced lipid droplet deposition in the liver with increasing activity of liver-derived enzymes in the plasma. On the other hand, it did not induce fibrosis or cirrhosis. Additionally, it was demonstrated that CDAHFD significantly impaired mitochondrial respiration with severe oxidative stress to the liver, which is associated with a decreasing mitochondrial DNA copy number and complex proteins. In the gene expression analysis of the liver, inflammatory and oxidative stress markers were significantly increased by CDAHFD. These results demonstrated that 1 week of feeding CDAHFD to mice induces steatohepatitis with mitochondrial dysfunction and severe oxidative stress, without fibrosis, which can partially mimic the early stage of NASH in humans.

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Neurotherapeutic Effect of Inula britannica var. Chinensis against H2O2-Induced Oxidative Stress and Mitochondrial Dysfunction in Cortical Neurons

Antioxidants ◽

10.3390/antiox10030375 ◽

2021 ◽

Vol 10 (3) ◽

pp. 375

Author(s):

Jin Young Hong ◽

Hyunseong Kim ◽

Junseon Lee ◽

Wan-Jin Jeon ◽

Seung Ho Baek ◽

...

Keyword(s):

Oxidative Stress ◽

Mitochondrial Dysfunction ◽

Cortical Neurons ◽

Inflammatory Diseases ◽

Neuroprotective Effect ◽

Neuroprotective Effects ◽

Neuronal Viability ◽

Inula Britannica ◽

Oxidative Effects

Inula britannica var. chinensis (IBC) has been used as a traditional medicinal herb to treat inflammatory diseases. Although its anti-inflammatory and anti-oxidative effects have been reported, whether IBC exerts neuroprotective effects and the related mechanisms in cortical neurons remain unknown. In this study, we investigated the effects of different concentrations of IBC extract (5, 10, and 20 µg/mL) on cortical neurons using a hydrogen peroxide (H2O2)-induced injury model. Our results demonstrate that IBC can effectively enhance neuronal viability under in vitro-modeled reaction oxygen species (ROS)-generating conditions by inhibiting mitochondrial ROS production and increasing adenosine triphosphate level in H2O2-treated neurons. Additionally, we confirmed that neuronal death was attenuated by improving the mitochondrial membrane potential status and regulating the expression of cytochrome c, a protein related to cell death. Furthermore, IBC increased the expression of brain-derived neurotrophic factor and nerve growth factor. Furthermore, IBC inhibited the loss and induced the production of synaptophysin, a major synaptic vesicle protein. This study is the first to demonstrate that IBC exerts its neuroprotective effect by reducing mitochondria-associated oxidative stress and improving mitochondrial dysfunction.

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