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1.
Toxicol Lett ; 323: 48-56, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32017980

RESUMO

Traditional Chinese medicine (TCM) has become a crucial cause of drug-induced liver injury (DILI). Differ from chemical medicines, TCM feature more complex and mostly indefinite components. This review aimed to clarify the classification, underlying mechanisms and targets of the risk components in TCM-induced liver injury to further guide the secure application of TCM. Relevant studies or articles published on the PubMed database from January 2008 to December 2019 were searched. Based on the different chemical structures of the risk ingredients in TCM, they are divided into alkaloids, glycosides, toxic proteins, terpenoids and lactones, anthraquinones, and heavy metals. According to whether drug metabolism is activated or hepatocytes are directly attacked during TCM-induced liver injury, the high-risk substances can be classified into metabolic activation, non-metabolic activation, and mixed types. Mechanisms of the hepatotoxic ingredients in TCM-induced hepatotoxicity, including cytochrome P450 (CYP450) induction, mitochondrial dysfunction, oxidative damage, apoptosis, and idiosyncratic reaction, were also summarized. The targets involved in the risk ingredient-induced hepatocellular injury mainly include metabolic enzymes, nuclear receptors, transporters, and signaling pathways. Our periodic review and summary on the risk signals of TCM-induced liver injury must be beneficial to the integrated analysis on the multi-component, multi-target, and multi-effect characteristics of TCM-induced hepatotoxicity.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Medicina Tradicional Chinesa/efeitos adversos , Ativação Metabólica , Apoptose/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/classificação , Sistema Enzimático do Citocromo P-450/fisiologia , Humanos , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Risco , Transdução de Sinais/efeitos dos fármacos
2.
Toxicol Lett ; 318: 74-85, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31654802

RESUMO

Metabolic flexibility defines the capacity of cells to respond to changes in nutrient status. Mitochondria are important mediators of metabolic flexibility and dysfunction is associated with metabolic inflexibility and pathology. Foodborne toxins are often overlooked as potential factors contributing to metabolic toxicity. Fusaric acid (FA), a neglected mycotoxin, is known to disrupt mitochondrial function. The aim of this study was to investigate the molecular mechanisms underlying a metabolic switch in response to FA. This study investigated the effects of FA on energy homeostasis in cultured human liver (HepG2) cells. HepG2 cells poised to undergo oxidative and glycolytic metabolism were exposed to a range of FA concentrations (4, 63 and 250 µg/mL) for 6 h. We determined mitochondrial toxicity, acetyl CoA levels and cell viability using luminometric, fluorometric and spectrophotometric methods. Expression of metabolic proteins (PDK1, PKM2, phosphorylated-PDH E1α and HIF-1α) and mRNAs (HIF-1α, PKM2, LDHa and PDK1) were determined using western blot and qPCR respectively. Our data connects a constitutive expression of HIF-1α in response to FA, to the inhibition of pyruvate decarboxylation through up-regulation of PDK-1 and phosphorylation of Pyruvate Dehydrogenase E1α subunit. Moreover, we highlight the potential of FA to induce a glucose "addiction" and phenotype reminiscent of the Warburg effect. The findings provide novel insights into the impact of this neglected foodborne mycotoxin in the dysregulation of energy metabolism.


Assuntos
Plasticidade Celular/efeitos dos fármacos , Microbiologia de Alimentos , Ácido Fusárico/toxicidade , Glicólise/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Fenótipo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Quinase Piruvato Desidrogenase (Transferência de Acetil) , Piruvato Desidrogenase (Lipoamida)/metabolismo
3.
PLoS Comput Biol ; 15(8): e1006661, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31437152

RESUMO

Multiple cellular organelles tightly orchestrate intracellular calcium (Ca2+) dynamics to regulate cellular activities and maintain homeostasis. The interplay between the endoplasmic reticulum (ER), a major store of intracellular Ca2+, and mitochondria, an important source of adenosine triphosphate (ATP), has been the subject of much research, as their dysfunction has been linked with metabolic diseases. Interestingly, throughout the cell's cytosolic domain, these two organelles share common microdomains called mitochondria-associated ER membranes (MAMs), where their membranes are in close apposition. The role of MAMs is critical for intracellular Ca2+ dynamics as they provide hubs for direct Ca2+ exchange between the organelles. A recent experimental study reported correlation between obesity and MAM formation in mouse liver cells, and obesity-related cellular changes that are closely associated with the regulation of Ca2+ dynamics. We constructed a mathematical model to study the effects of MAM Ca2+ dynamics on global Ca2+ activities. Through a series of model simulations, we investigated cellular mechanisms underlying the altered Ca2+ dynamics in the cells under obesity. We predict that, as the dosage of stimulus gradually increases, liver cells from obese mice will reach the state of saturated cytosolic Ca2+ concentration at a lower stimulus concentration, compared to cells from healthy mice.


Assuntos
Sinalização do Cálcio/fisiologia , Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Modelos Biológicos , Obesidade/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Biologia Computacional , Simulação por Computador , Hepatócitos/metabolismo , Humanos , Fosfatos de Inositol/metabolismo , Conceitos Matemáticos , Redes e Vias Metabólicas , Camundongos , Mitocôndrias Hepáticas/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
4.
Nutrients ; 11(9)2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31443411

RESUMO

Hyperglycemia and hyperlipidemia are the hallmarks of diabetes and obesity. Experimental and epidemiological studies have suggested that dietary management and caloric restriction are beneficial in reducing the complications of diabesity. Studies have suggested that increased availability of energy metabolites like glucose and saturated fatty acids induces metabolic, oxidative, and mitochondrial stress, accompanied by inflammation that may lead to chronic complications in diabetes. In the present study, we used human hepatoma HepG2 cells to investigate the effects of high glucose (25 mM) and high palmitic acid (up to 0.3 mM) on metabolic-, inflammatory-, and redox-stress-associated alterations in these cells. Our results showed increased lipid, protein, and DNA damage, leading to caspase-dependent apoptosis and mitochondrial dysfunction. Glucolipotoxicity increased ROS production and redox stress appeared to alter mitochondrial membrane potential and bioenergetics. Our results also demonstrate the enhanced ability of cytochrome P450s-dependent drug metabolism and antioxidant adaptation in HepG2 cells treated with palmitic acid, which was further augmented with high glucose. Altered NF-kB/AMPK/mTOR-dependent cell signaling and inflammatory (IL6/TNF-α) responses were also observed. Our results suggest that the presence of high-energy metabolites enhances apoptosis while suppressing autophagy by inducing inflammatory and oxidative stress responses that may be responsible for alterations in cell signaling and metabolism.


Assuntos
Apoptose/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Glucose/toxicidade , Hepatócitos/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ácido Palmítico/toxicidade , Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/efeitos dos fármacos , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Mediadores da Inflamação/metabolismo , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , NF-kappa B/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
5.
Aquat Toxicol ; 214: 105264, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31377504

RESUMO

A by-product of mitochondrial substrate oxidation and electron transfer to generate cellular energy (ATP) is reactive oxygen species (ROS). Superoxide anion radical and hydrogen peroxide (H2O2) are the proximal ROS produced by the mitochondria. Because low levels of ROS serve critical regulatory roles in cell physiology while excessive levels or inappropriately localized ROS result in aberrant physiological states, mitochondrial ROS need to be tightly regulated. While it is known that regulation of mitochondrial ROS involves balancing the rates of production and removal, the effects of stressors on these processes remain largely unknown. To illuminate how stressors modulate mitochondrial ROS homeostasis, we investigated the effects of temperature and cadmium (Cd) on H2O2 emission and consumption in rainbow trout liver mitochondria. We show that H2O2 emission rates increase with temperature and Cd exposure. Energizing mitochondria with malate-glutamate or succinate increased the rate of H2O2 emission; however, Cd exposure imposed different patterns of H2O2 emission depending on the concentration and substrate. Specifically, mitochondria respiring on malate-glutamate exhibited a saturable graded concentration-response curve that plateaued at 5 µM while mitochondria respiring on succinate had a biphasic concentration-response curve characterized by a spike in the emission rate at 1 µM Cd followed by gradual diminution at higher Cd concentrations. To explain the observed substrate- and concentration-dependent effects of Cd, we sequestered specific mitochondrial ROS-emitting sites using blockers of electron transfer and then tested the effect of the metal. The results indicate that the biphasic H2O2 emission response imposed by succinate is due to site IIF but is further modified at sites IQ and IIIQo. Moreover, the saturable graded H2O2 emission response in mitochondria energized with malate-glutamate is consistent with effect of Cd on site IF. Additionally, Cd and temperature acted cooperatively to increase mitochondrial H2O2 emission suggesting that increased toxicity of Cd at high temperature may be due to increased oxidative insult. Surprisingly, despite their clear stimulatory effect on H2O2 emission, Cd, temperature and bioenergetic status did not affect the kinetics of mitochondrial H2O2 consumption; the rate constants and half-lives for all the conditions tested were similar. Overall, our study indicates that the production processes of rainbow trout liver mitochondrial H2O2 metabolism are highly responsive to stressors and bioenergetics while the consumption processes are recalcitrant. The latter denotes the presence of a robust H2O2 scavenging system in liver mitochondria that would maintain H2O2 homeostasis in the face of increased production and reduced scavenging capacity.


Assuntos
Cádmio/toxicidade , Metabolismo Energético , Mitocôndrias Hepáticas/metabolismo , Consumo de Oxigênio/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Temperatura , Animais , Respiração Celular/efeitos dos fármacos , Transporte de Elétrons , Feminino , Peróxido de Hidrogênio/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , NAD/metabolismo , Oncorhynchus mykiss/fisiologia , Poluentes Químicos da Água/toxicidade
6.
Chemosphere ; 236: 124357, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31325826

RESUMO

The mechanisms involved in changes in energy metabolism caused by excessive exposure to fluoride (F) are not completely understood. The present study employed proteomic tools to investigate the molecular mechanisms underlying the dose- and time-dependency of the effects of F in the rat liver mitochondria. Thirty-six male Wistar rats received water containing 0, 15 or 50 mgF/L (as NaF) for 20 or 60 days. Rat liver mitochondria were isolated and the proteome profiles were examined using label-free quantitative nLC-MS/MS. PLGS software was used to detect changes in protein expression among the different groups. The bioinformatics analysis was done using the software CYTOSCAPE® 3.0.7 (Java®) with the aid of ClueGo plugin. The dose of 15 mgF/L, when administered for 20 days, reduced glycolysis, which was counterbalanced by an increase in other energetic pathways. At 60 days, however, an increase in all energy pathways was observed. On the other hand, the dose of 50 mgF/L, when administered for 20 days, reduced the enzymes involved in all energetic pathways, indicating a lower rate of energy production, with less generation of ROS and consequent reduction of antioxidant enzymes. However, when the 50 mgF/L dose was administered for 60 days, an increase in energy metabolism was seen but in general no changes were observed in the antioxidant enzymes. Except for the group treated with 50 mgF/L for 20 days, all the other groups had alterations in proteins in attempt to maintain calcium homeostasis and avoid apoptosis. The results suggest that the organism seems to adapt to the effects of F over time, activating pathways to reduce the toxicity of this ion. Ultimately, our findings corroborate the safety of the use of fluoride for caries control.


Assuntos
Metabolismo Energético/efeitos dos fármacos , Fluoretos/toxicidade , Glicólise/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , Fígado/metabolismo , Masculino , Proteômica , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas em Tandem
7.
Nutrients ; 11(7)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315289

RESUMO

Female mice fed a cafeteria diet (FCaf) develop higher liver steatosis and oxidative stress than males (MCaf) as a consequence of unresolved ER stress. Here, we investigated whether mitochondria play a role in this sex difference. The isolated mitochondria from FCaf showed more signs of oxidative stress than those of MCaf, correlated with a reduced content of GSH, increased amount of reactive oxygen species (ROS), and lower activities of enzymes involved in ROS neutralisation. Mitochondria from FCaf and MCaf livers exhibited lower rates of succinate-driven state III respiration and reduced ATPase activity in intact coupled mitochondria compared to their controls fed a standard diet (FC and MC), with no differences between the sexes. Fatty acid oxidation in mitochondria and peroxisomes was higher in MCaf and FCaf compared to their respective controls. In the intact perfused liver, there was no difference between sex or diet regarding the fatty acid oxidation rate. These results indicated that cafeteria diet did not affect mitochondrial energy metabolism, even in FCaf livers, which have higher steatosis and cellular oxidative stress. Nevertheless, the increase in mitochondrial ROS generation associated with a decrease in the antioxidant defence capacity, probably contributes to inducing or reinforcing the ER stress in FCaf livers.


Assuntos
Ração Animal , Dieta/veterinária , Fígado Gorduroso/etiologia , Mitocôndrias Hepáticas/metabolismo , Obesidade/etiologia , Estresse Oxidativo/fisiologia , Criação de Animais Domésticos , Animais , Dióxido de Carbono/química , Dióxido de Carbono/metabolismo , Radioisótopos de Carbono , Fígado Gorduroso/patologia , Feminino , Masculino , Camundongos , Consumo de Oxigênio
8.
Int J Mol Sci ; 20(13)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261843

RESUMO

The antioxidant effect of salidroside has been proven, but its role in liver injury is poorly understood. In this study, we aimed to evaluate the protective effects and mechanism of salidroside on liver injury induced by carbon tetrachloride (CCl4) in vivo. Mice were pretreated with salidroside (60 mg/kg, intraperitoneally injected, i.p.) once per day for 14 consecutive days and then administered with CCl4 (15.95 g/kg, i.p.) for 24 h to produce a liver injury model. Salidroside attenuated hepatic transaminase elevation in serum and ameliorated liver steatosis and necrosis, thereby suggesting its protective effect on the liver. Salidroside antagonized CCl4-induced toxicity by equilibrating antioxidation system, thereby inhibiting reactive oxygen species accumulation, and restoring mitochondrial structure and function. Salidroside exerts antioxidant and liver-protective effects by selectively inhibiting the activation of genes, including growth arrest and DNA -damage-inducible 45 α (Gadd45a), mitogen-activated protein kinase 7 (Mapk7), and related RAS viral oncogene homolog 2 (Rras2), which induce oxidative stress in the mitogen-activated protein kinase pathway. These results revealed that salidroside can protect the liver from CCl4-induced injury by resisting oxidative stress and protecting mitochondrial function.


Assuntos
Antioxidantes/uso terapêutico , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Glucosídeos/uso terapêutico , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo , Fenóis/uso terapêutico , Animais , Antioxidantes/farmacologia , Tetracloreto de Carbono/toxicidade , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Glucosídeos/farmacologia , Sistema de Sinalização das MAP Quinases , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias Hepáticas/metabolismo , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Fenóis/farmacologia
9.
Food Chem Toxicol ; 132: 110694, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31344369

RESUMO

The present study evaluates the effects of low-level long-term exposure to bisphenol A (BPA) and bisphenol S (BPS) on serum biochemical markers, glucose homeostasis, mitochondrial energy metabolism, biogenesis and dynamics, and redox status in livers of Wistar rats. While only the exposure to BPS induces a significant body mass gain after 21 weeks, both compounds alter serum lipid levels and lead to the development of glucose intolerance. Regarding mitochondrial metabolism, both bisphenols augment the electron entry by complex II relative to complex I in the mitochondrial respiratory chain (MRC), and reduce mitochondrial content; BPA reduces OXPHOS capacity and uncouples respiration (relative to maximal capacity of MRC) but promotes a significant increase in fatty acid oxidation. Either exposure to BPA or BPS leads to an increase in mitochondrial-derived reactive oxygen species, mainly at complex I. Additionally, BPA and BPS significantly upregulate the expression levels of dynamin-related protein 1 related to mitochondrial fission, while BPA downregulates the expression of proliferator-activated receptor gamma coactivator 1 alpha, a master regulator of mitochondrial biogenesis. In summary, our data shows that exposure to both compounds alters metabolic homeostasis and mitochondrial energy metabolism, providing new mechanisms by which BPA and BPS impair the mitochondrial metabolism.


Assuntos
Compostos Benzidrílicos/farmacologia , Teste de Tolerância a Glucose , Mitocôndrias Hepáticas/efeitos dos fármacos , Fenóis/farmacologia , Sulfonas/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Lipídeos/sangue , Masculino , Mitocôndrias Hepáticas/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos , Tamanho do Órgão/efeitos dos fármacos , Oxirredução , Fosforilação Oxidativa/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
10.
C R Biol ; 342(5-6): 209-219, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31151779

RESUMO

The aim of this study was to show, for the first time, the effect of a hypercaloric diet on the mitochondrial reshuffle of hepatocytes during the progression from steatosis to steatohepatitis to cirrhosis in Psammomys obesus, a typical animal model of the metabolic syndrome. Metabolic and oxidative stresses were induced by feeding the animal through a standard laboratory diet (SD) for nine months. Metabolic parameters, liver malondialdehyde (MDA) and glutathione (GSH), were evaluated. The pathological evolution was examined by histopathology and immunohistochemistry, using CD3 and CD20 antibodies. The dynamics of the mitochondrial structure was followed by transmission electron microscopy. SD induced a steatosis in this animal that evolved under the effect of oxidative and metabolic stress by the appearance of adaptive inflammation and fibrosis leading the animal to the cirrhosis stage with serious hepatocyte damage by the triggering, at first the mitochondrial fusion-fission cycles, which attempted to maintain the mitochondria intact and functional, but the hepatocellular oxidative damage was increased inducing a vicious circle of mitochondrial alteration and dysfunction and their elimination by mitophagy. P. obesus is an excellent animal model of therapeutic research that targets mitochondrial dysfunction in the progression of steatosis.


Assuntos
Gerbillinae , Hiperfagia/metabolismo , Resistência à Insulina , Fígado/metabolismo , Mitocôndrias Hepáticas/metabolismo , Infiltração de Neutrófilos , Estresse Oxidativo , Animais , Dieta , Modelos Animais de Doenças , Progressão da Doença , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Glutationa/metabolismo , Hiperfagia/patologia , Inflamação/metabolismo , Inflamação/patologia , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Mitocôndrias Hepáticas/patologia
11.
Pancreatology ; 19(5): 638-645, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31204259

RESUMO

BACKGROUND: /Objectives: Evaluation of the local and systemic effects of aging on the severity of acute pancreatitis (AP) in an experimental rat model in elderly animals. METHODS: AP was induced in Wistar rats by intraductal 2.5% taurocholate injection and divided into two groups: Young (3 month old) and Aged (18 month old). Two and 24 h after AP induction blood samples were collected for determinations of amylase, AST, ALT, urea, creatinine, glucose, and of plasma I-FABP. TNF-α and IL-6 levels were determined in serum and ascitic fluid. Liver mitochondrial function and malondialdehyde (MDA) contents, pancreas histological analysis, and pulmonar myeloperoxidade (MPO) activity were performed. Bacterial translocation was evaluated by bacterial cultures of pancreas. RESULTS: A significant increase in serum amylase, AST, ALT, urea, creatinine, glucose, I-FABP, and IL-6 levels, and a reduction in serum and ascitic fluid TNF-α levels were observed in the aged group compared to the young group. Liver mitochondrial dysfunction, MDA contents, and pulmonary MPO activity were increased in the Aged AP group compared to the Young AP group. Positive bacterial cultures obtained from pancreas tissue in aged group were significantly increased compared to the young group. Acinar necrosis was also increased in aged AP group when compared to young AP group. CONCLUSION: Aging worsens the course of acute pancreatitis evidenced by increased local and systemic lesions and increased bacterial translocation.


Assuntos
Envelhecimento/patologia , Pancreatite/patologia , Doença Aguda , Animais , Citocinas/sangue , Proteínas de Ligação a Ácido Graxo/metabolismo , /fisiopatologia , Peroxidação de Lipídeos , Masculino , Mitocôndrias Hepáticas/metabolismo , Necrose , Oxirredução , Pancreatite/cirurgia , Peroxidase/metabolismo , Fosforilação , Ratos , Ratos Wistar
12.
Am J Physiol Endocrinol Metab ; 317(2): E374-E387, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31211616

RESUMO

Mitochondria are dynamic organelles with diverse functions in tissues such as liver and skeletal muscle. To unravel the mitochondrial contribution to tissue-specific physiology, we performed a systematic comparison of the mitochondrial proteome and lipidome of mice and assessed the consequences hereof for respiration. Liver and skeletal muscle mitochondrial protein composition was studied by data-independent ultra-high-performance (UHP)LC-MS/MS-proteomics, and lipid profiles were compared by UHPLC-MS/MS lipidomics. Mitochondrial function was investigated by high-resolution respirometry in samples from mice and humans. Enzymes of pyruvate oxidation as well as several subunits of complex I, III, and ATP synthase were more abundant in muscle mitochondria. Muscle mitochondria were enriched in cardiolipins associated with higher oxidative phosphorylation capacity and flexibility, in particular CL(18:2)4 and 22:6-containing cardiolipins. In contrast, protein equipment of liver mitochondria indicated a shuttling of complex I substrates toward gluconeogenesis and ketogenesis and a higher preference for electron transfer via the flavoprotein quinone oxidoreductase pathway. Concordantly, muscle and liver mitochondria showed distinct respiratory substrate preferences. Muscle respired significantly more on the complex I substrates pyruvate and glutamate, whereas in liver maximal respiration was supported by complex II substrate succinate. This was a consistent finding in mouse liver and skeletal muscle mitochondria and human samples. Muscle mitochondria are tailored to produce ATP with a high capacity for complex I-linked substrates. Liver mitochondria are more connected to biosynthetic pathways, preferring fatty acids and succinate for oxidation. The physiologic diversity of mitochondria may help to understand tissue-specific disease pathologies and to develop therapies targeting mitochondrial function.


Assuntos
Metabolismo Energético/fisiologia , Fígado/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/metabolismo , Proteoma/metabolismo , Animais , Feminino , Humanos , Fígado/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Musculares/metabolismo , Proteínas Mitocondriais/análise , Músculo Esquelético/química , Especificidade de Órgãos , Mapeamento de Peptídeos/métodos , Proteoma/análise
13.
Vopr Pitan ; 88(2): 32-39, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31233686

RESUMO

Oxidative stress is a universal mechanism of cellular damage of hepatocytes, leading to a decrease in the detoxification function of the liver, which is especially important during oncogenesis. An early correction of these mechanisms by lipophilic essential nutrients could increase the effectiveness of antitumor treatment and prevent the development and progress of cancer. Aim to study the effect of separate and combined use of ω-3 PUFA and vitamin D3 on the intensity of free radical processes, mitochondrial swelling and cytochrome c content in the liver mitochondrial fraction of the tumor-bearing rats during the intensive growth of the tumor has been studied. Material and methods. Studies were carried out on white outbred female rats weighing 130-150 g, which were divided into 5 groups (each n=12). Guerin's carcinoma was used as a model of malignant neoplasm. Carcinoma transplantation was carried out by subcutaneous injection of 0.5 ml of a 30% suspension of cancer cells into saline in the upper thigh region of the right limb. ω-3 PUFAs (120 mg/kg of body weight, per os) and vitamin D3 (600 IU/kg of body weight, per os) were pre-administered for 28 days before the transplantation of Guerin's carcinoma and after transplantation for the entire period of tumor growth in the body (14 days). Liver mitochondrial fraction was isolated by differential centrifugation. The intensity of lipid peroxidation was judged by using spectrophotometry by the content of primary, secondary, and tertiary products in isopropanol extracts. The rate of formation of the superoxide radical was recorded in a test with nitro-blue tetrazolium, the swelling of mitochondria was assessed by a decrease in the optical density of isolated mitochondria, the content of cytochrome c in the mitochondrial and cytosolic fractions was determined by multi-wavelength visible light spectroscopy. Results and discussion. An increase in the content of primary (diene and triene conjugates), secondary (ketodienes; conjugated trienes; TBA-active products) and terminal (Schiff bases) lipid peroxidation products with a simultaneous increase in the generation of superoxide anion-radical was found in the liver mitochondrial fraction of the tumorbearing rats. With the administration of ω-3 PUFA and vitamin D3, both separately and especially when used together, a decrease in the intensity of free radical processes in liver mitochondrial fraction of tumor-bearing rats has been observed. At the same time, mitochondrial swelling decreased, this prevented the release of cytochrome c from mitochondria into cytosol. Conclusion. The administration of the complex ω-3 PUFA and vitamin D3 reduces the processes of lipid peroxidation in the mitochondrial fraction of the liver of tumor-bearing rats while simultaneously restoring the functional ability of mitochondria.


Assuntos
Colecalciferol/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Neoplasias Experimentais/metabolismo , Superóxidos/metabolismo , Animais , Citocromos c/metabolismo , Feminino , Mitocôndrias Hepáticas/patologia , Neoplasias Experimentais/patologia , Ratos
14.
Int J Mol Sci ; 20(10)2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31137890

RESUMO

While mitochondrial dysfunction is acknowledged as a major feature of aging, much less is known about the role of mitochondria in extended longevity. Livers from aged (28-month-old) and extremely aged (32-month-old) rats were analyzed for citrate synthase activity, mitochondrial transcription factor A (TFAM) amount, mitochondrial DNA (mtDNA), and 4.8 Kb "common deletion" contents. None of the assayed parameters differed significantly between age groups. TFAM-binding to mtDNA and the incidence of 8-oxo-deoxyguanosine in specific mtDNA regions, encompassing the origins of mtDNA replication (D-loop and Ori-L) and the 16-bp long direct repeat 1 (DR1) of the 4.8 Kb deletion, were determined. A decrease in TFAM binding was unveiled at all regions in extremely aged in comparison with aged rats. Reduced incidence of oxidized purines at all assayed regions was detected in 32-month-old rats compared with the 28-month-old group. A significant positive correlation between the incidence of 8-oxo-deoxoguanosine and TFAM-bound mtDNA was found at D-Loop and Ori-L regions only in 28-month-old rats. The absence of such correlation in 32-month-old rats indicates a different, fine-tuned regulation of TFAM binding in the two age groups and supports the existence of two different paces in aging and extended aging.


Assuntos
Envelhecimento/metabolismo , Dano ao DNA , Mitocôndrias Hepáticas/metabolismo , Fatores de Transcrição/metabolismo , Envelhecimento/genética , Animais , DNA Mitocondrial/metabolismo , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Masculino , Ligação Proteica , Ratos
15.
Appl Biochem Biotechnol ; 189(2): 647-660, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31093908

RESUMO

Based on the various pharmacological activities of tamarixetin, the present study investigated the cytotoxicity property of tamarixetin in human liver cancer cells including PLC/PRF/5 and HepG2 cells, and their xenografted tumor nude mice. In cells, tamarixetin incubation resulted in the suppression on cell viability; enhanced cell apoptosis rate, LDH release, caspase-3 activation, and reactive oxygen species accumulation; and decreased mitochondrial membrane potential in a dose-dependent manner. Tamarixetin inhibited the growth of PLC/PRF/5- and HepG2-xenografted tumors in BALB/c nude mice after 14-day administration without influencing their bodyweights and organ functions including liver and spleen. Tamarixetin enhanced the expression levels of pro-apoptotic proteins including Bax and cleaved caspase-3 and inhibited the expression levels of anti-apoptotic proteins including Bcl-2 and Bcl-xL in liver cancer cells and their xenografted tumor tissues. Furthermore, tamarixetin significantly suppressed the phosphorylation of ERKs and AKT in both PLC/PRF/5 and HepG2 cells, and tumor tissues. All present data suggest that tamarixetin displays pro-apoptotic properties in liver cancer cells related to the mitochondria apoptotic pathway via regulating the ERKs and AKT signaling.


Assuntos
Apoptose/efeitos dos fármacos , Dissacarídeos/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Mitocôndrias Hepáticas/metabolismo , Quercetina/análogos & derivados , Animais , Caspase 3/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias Hepáticas/patologia , Proteínas de Neoplasias/metabolismo , Quercetina/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Biochem Mol Toxicol ; 33(8): e22345, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31066974

RESUMO

For fasiglifam (TAK875) and its metabolites the substance-specific mechanisms of liver toxicity were studied. Metabolism studies were run to identify a putatively reactive acyl glucuronide metabolite. In vitro cytotoxicity and caspase 3/7 activation were assessed in primary human and dog hepatocytes in 2D and 3D cell culture. Involvement of glutathione (GSH) detoxication system in mediating cytotoxicity was determined by assessing potentiation of cytotoxicity in a GSH depleted in vitro system. In addition, potential mitochondrial liabilities of the compounds were assessed in a whole-cell mitochondrial functional assay. Fasiglifam showed moderate cytotoxicity in human primary hepatocytes in the classical 2D cytotoxicity assays and also in the complex 3D human liver microtissue (hLiMT) after short-term treatment (24 hours or 48 hours) with TC50 values of 56 to 68 µM (adenosine triphosphate endpoint). The long-term treatment for 14 days in the hLiMT resulted in a slight TC50 shift over time of 2.7/3.6 fold lower vs 24-hour treatment indicating possibly a higher risk for cytotoxicity during long-term treatment. Cellular GSH depletion and impairment of mitochondrial function by TAK875 and its metabolites evaluated by Seahorse assay could not be found being involved in DILI reported for TAK875. The acyl glucuronide metabolites of TAK875 have been finally identified to be the dominant reason for liver toxicity.


Assuntos
Benzofuranos/toxicidade , Ácidos Graxos não Esterificados/metabolismo , Fígado/efeitos dos fármacos , Receptores Acoplados a Proteínas-G/agonistas , Sulfonas/toxicidade , Animais , Benzofuranos/metabolismo , Células Cultivadas , Cães , Glutationa/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Ratos , Receptores Acoplados a Proteínas-G/metabolismo , Sulfonas/metabolismo
17.
Oxid Med Cell Longev ; 2019: 4353791, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31093314

RESUMO

Targeting mitochondria as a hepatic-protective strategy has gained attention, because of their important roles in energy production, adjustment of apoptosis, and generation of reactive oxygen species. To promote the discovery of natural mitochondria-targeted hepatic-protectants, we established a hepatocellular mitochondria-based capturing method by coupling affinity ultrafiltration with liquid chromatography/mass spectrometry (LC/MS), which is suitable for identifying mitochondrial ligands from medicinal herbs (MHs). After evaluating the feasibility of the method, it was applied for capturing mitochondria-targeting constituents from Peucedani Radix extract. A total of 10 active compounds were identified by LC/MS, all of which were newly identified mitochondrial ligands. The mitochondria-remedying activity of 4 of the 10 hits was confirmed by pharmacological tests in vitro. Additionally, the hepatic-protective abilities of 4 hits were verified in both carbon tetrachloride-damaged liver L02 cells and mice. These results indicated that the method could be used for identifying hepatic mitochondria-targeting constituents in MHs, which might be beneficial for hepatic-protective development.


Assuntos
Fígado/metabolismo , Mitocôndrias Hepáticas/metabolismo , Plantas Medicinais/química , Substâncias Protetoras/farmacologia , Animais , Fígado/efeitos dos fármacos , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/ultraestrutura , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Extratos Vegetais/farmacologia , Ratos Sprague-Dawley , Padrões de Referência
18.
Molecules ; 24(10)2019 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-31126054

RESUMO

Dexamethasone is a glucocorticoid analog, which is reported to induce insulin resistance and to exacerbate diabetic symptoms. In this study, we investigated the association between mitochondrial dysfunction and the pathophysiology of dexamethasone-induced insulin resistance. An insulin resistance model in 3T3-L1 adipocyte was established by 48-h treatment of 1 µM dexamethasone, followed with the detection of mitochondrial function. Results showed that dexamethasone impaired insulin-induced glucose uptake and caused mitochondrial dysfunction. Abnormality in mitochondrial function was supported by decreased intracellular ATP and mitochondrial membrane potential (MMP), increased intracellular and mitochondrial reactive oxygen species (ROS) and mtDNA damage. Mitochondrial dynamic changes and biogenesis were suggested by decreased Drp1, increased Mfn2, and decreased PGC-1, NRF1, and TFam, respectively. The mitochondrial DNA (mtDNA) copy number exhibited no change while the mitochondrial mass increased. In agreement, studies in isolated mitochondria from mouse liver also showed dexamethasone-induced reduction of mitochondrial respiratory function, as suggested by decreased mitochondrial respiration controlling rate (RCR), lower MMP, declined ATP synthesis, opening of the mitochondrial permeability transition pore (mPTP), damage of mtDNA, and the accumulation of ROS. In summary, our study suggests that mitochondrial dysfunction occurs along with dexamethasone-induced insulin resistance in 3T3 L1 adipocytes and might be a potential mechanism of dexamethasone-induced insulin resistance.


Assuntos
Adipócitos/citologia , Dexametasona/efeitos adversos , Resistência à Insulina , Mitocôndrias Hepáticas/efeitos dos fármacos , Células 3T3-L1 , Trifosfato de Adenosina/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Células Cultivadas , Dano ao DNA , DNA Mitocondrial/efeitos dos fármacos , Modelos Animais de Doenças , Glucose/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Mitocôndrias Hepáticas/genética , Mitocôndrias Hepáticas/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos
19.
Am J Physiol Endocrinol Metab ; 317(2): E298-E311, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31039007

RESUMO

The impact of sexual dimorphism and mitophagy on hepatic mitochondrial adaptations during the treatment of steatosis with physical activity are largely unknown. Here, we tested if deficiencies in liver-specific peroxisome proliferative activated-receptor-γ coactivator-1α (PGC-1α), a transcriptional coactivator of biogenesis, and BCL-2/ADENOVIRUS EIB 19-kDa interacting protein (BNIP3), a mitophagy regulator, would impact hepatic mitochondrial adaptations (respiratory capacity, H2O2 production, mitophagy) to a high-fat diet (HFD) and HFD plus physical activity via voluntary wheel running (VWR) in both sexes. Male and female wild-type (WT), liver-specific PGC-1α heterozygote (LPGC-1α), and BNIP3 null mice were thermoneutral housed (29-31°C) and divided into three groups: sedentary-low-fat diet (LFD), 16 wk of (HFD), or 16 wk of HFD with VWR for the final 8 wk (HFD + VWR) (n = 5-7/sex/group). HFD did not impair mitochondrial respiratory capacity or coupling in any group; however, HFD + VWR significantly increased maximal respiratory capacity only in WT and PGC-1α females. Males required VWR to elicit mitochondrial adaptations that were inherently present in sedentary females including greater mitochondrial coupling control and reduced H2O2 production. Females had overall reduced markers of mitophagy, steatosis, and liver damage. Steatosis and markers of liver injury were present in sedentary male mice on the HFD and were effectively reduced with VWR despite no resolution of steatosis. Overall, reductions in PGC-1α and loss of BNIP3 only modestly impacted mitochondrial adaptations to HFD and HFD + VWR with the biggest effect seen in BNIP3 females. In conclusion, hepatic mitochondrial adaptations to HFD and treatment of HFD-induced steatosis with VWR are more dependent on sex than PGC-1α or BNIP3.


Assuntos
Dieta Hiperlipídica , Mitocôndrias Hepáticas/metabolismo , Esforço Físico , Animais , Dieta com Restrição de Gorduras , Feminino , Regulação da Expressão Gênica , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Consumo de Oxigênio , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Condicionamento Físico Animal , Comportamento Sedentário , Caracteres Sexuais
20.
Biomed Pharmacother ; 115: 108948, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31078037

RESUMO

Mitochondrial dysfunction has been documented to play a crucial role in the pathogenesis of liver injury. In the present study, we investigated the role of rotenone, a mitochondrial complex-1 inhibitor, in carbon tetrachloride (CCl4) -induced acute liver injury, as well as the underlying mechanisms. Before CCl4 administration, the mice were pretreated with rotenone at a dose of 250 ppm in food for three days. Then CCl4 was administered to the mice for 16 h by intraperitoneal injection. The liver injury, mitochondrial status, oxidative stress, and inflammation were examined. Strikingly, CCl4 treatment markedly induced liver injury as shown by enhanced serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) and morphological lesions (HE stating), which was significantly attenuated by rotenone treatment in line with the reduced activity of mitochondrial complex-1. Meanwhile, oxidative stress markers of malondialdehyde (MDA), 4-hydroxynonenal (HNE), and dihydroethidium (DHE) and the inflammatory markers of IL-1ß, MCP-1, TNF-α, TLR-4, and IL-6 were also significantly suppressed by rotenone. More importantly, the mitochondrial abnormalities shown by the reduction of SOD2, mitochondrial transcription factor A (TFAM), mitochondrial NADH dehydrogenase subunit 1 (mtND1), and Cytb were significantly restored, indicating that rotenone protected against mitochondrial damage induced by CCl4 in liver. Moreover, rotenone treatment alone did not significantly alter liver morphology and liver enzymes ALT and AST. CYP2E1, a metabolic enzyme of CCl4, was also not significantly affected by rotenone. In conclusion, rotenone protected the liver from CCl4-induced damage possibly by inhibiting the mitochondrial oxidative stress and inflammation.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Rotenona/farmacologia , Animais , Tetracloreto de Carbono , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias Hepáticas/metabolismo
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