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1.
Electron. j. biotechnol ; 44: 19-24, Mar. 2020. ilus, graf
Article in English | LILACS | ID: biblio-1087631

ABSTRACT

BACKGROUND: Pyruvic acid (PA), a vital α-oxocarboxylic acid, plays an important role in energy and carbon metabolism. The oleaginous yeast Yarrowia lipolytica (Y. lipolytica) has considerable potential for the production of PA. An increased NaCl concentration reportedly increases the biomass and PA yield of Y. lipolytica. RESULTS: To increase the yield of PA, the NaCl-tolerant Y. lipolytica A4 mutant was produced using the atmospheric and room temperature plasma method of mutation. The A4 mutant showed growth on medium containing 160 g/L NaCl. The PA yield of the A4 mutant reached 97.2 g/L at 120 h (0.795 g/g glycerol) in a 20-L fermenter with glycerol as the sole carbon source, which was 28.9% higher than that of the parental strain. CONCLUSION: The PA yield from Y. lipolytica can be improved by increasing its NaCl tolerance.


Subject(s)
Pyruvic Acid/metabolism , Yarrowia/genetics , Yarrowia/metabolism , Osmotic Pressure , Yeasts , Carbon/metabolism , Sodium Chloride , Bioreactors , Salt Tolerance/genetics , Fermentation , Glycerol/metabolism , Mutation
2.
Bol. latinoam. Caribe plantas med. aromát ; 18(5): 504-517, sept. 2019. ilus, tab, graf
Article in English | LILACS | ID: biblio-1008288

ABSTRACT

Nowdays it is established that ischemic brain damage like ischemic stroke is one of the leading cause of death and disability in the population that assumes relevance development of anti-ischemic drugs. The work studied the anti-hypoxic and anti-ischemic effect of 7 plant extracts. Antihypoxic activity was assessed on models of hypobaric, hypercapnic, histotoxic, hematotoxic hypoxia. Anti-ischemic activity of test-extracts was studied on the focal cerebral ischemia model. Administration of Tagetes patula, Gaillardia pulchella, Sorbaria sorbifolia, Grossularia reclinata, Ribes nigrum, Rubus caesius and Lysimachia punctata extracts contributed to the necrosis zone reduction by 56.6% (p<0.05); 37.3% (p<0.05); 73.2% (p<0.05); 49.4% (p<0.05); 42.5% (p<0.05); 85.5% (p<0.05); 44.2% (p<0.05) and also restored aerobic metabolism in brain tissue. Test - objects increased of the animal lifespan under hypoxia conditions. Based on the data obtained, it is assumed that further studies of North Caucasus flora plant extracts as cerebro-protective agents are promising.


Hoy en día, se ha establecido que el daño cerebral isquémico, como el accidente cerebrovascular isquémico, es una de las principales causas de muerte y discapacidad en la población lo cual hace relevante el desarrollo fármacos antiisquémicos. En este trabajo se estudió el efecto antihipóxico y antiisquémico de siete extractos de plantas. La actividad antihipóxica se evaluó en modelos de hipoxia hipocrática, hipercápnica, histotóxica y hematotóxica. La actividad antiisquémica de los extractos de prueba se estudió en el modelo de isquemia cerebral focal. La administración de los extractos de Tagetes patula; Gaillardia pulchella; Sorbaria sorbifolia; Grossularia reclinata; Ribes nigrum; Rubus caesius y Lysimachia punctata contribuyeron a la reducción de la zona de necrosis en un 56,6% (p<0,05); 37,3% (p<0,05); 73,2% (p<0,05); 49,4% (p<0,05); 42,5% (p<0,05); 85,5% (p<0,05); 44.2% (p<0.05), respectivamente, además, de restaurar el metabolismo aeróbico en el tejido cerebral. Comparado con el control, se observó un aumento en el tiempo de sobrevida del animal en condiciones de hipoxia. Sobre la base de los interesantes datos obtenidos, se sugiere estudios adicionales de extractos de plantas de la flora del Cáucaso Norte como agentes protectores del cerebro.


Subject(s)
Animals , Male , Mice , Rats , Plant Extracts/therapeutic use , Brain Ischemia/drug therapy , Hypoxia/drug therapy , Enzyme-Linked Immunosorbent Assay , Adenosine Triphosphate/analysis , Rats, Wistar , Lactic Acid/analysis , Pyruvic Acid/analysis , Mice, Inbred BALB C
3.
Article in English | WPRIM | ID: wpr-741711

ABSTRACT

BACKGROUND/OBJECTIVES: Oxidative stress is a major effector of various diseases; accordingly, antioxidants are frequently ingested in order to prevent or alleviate disease symptoms. Kimchi contains various natural antioxidants, and it is known that the functional activity varies depending on the ingredients and fermentation state. Black raspberries (BR) contain various bioactive compounds with antioxidant effects. This study investigated the antioxidant and liver-protection effects of kimchi supplemented with black raspberry juice powder (BJP). MATERIALS/METHODS: BJP-added kimchi (BAK; at 0.5%, 1%, and 2% concentrations of BJP) and control (without BJP) were prepared and fermented at 4℃ for 4 weeks. Changes in the antioxidant effects of BAK during fermentation were investigated. In addition, the protective activity of BAK against oxidative stress was investigated in a liver cirrhosis-induced animal model in vivo. RESULTS: BAK groups showed the acidity and pH of optimally ripened (OR) kimchi at 2 weeks of fermentation along with the highest lactic acid bacterial counts. Additionally, BAK groups displayed a higher content of phenolic compounds and elevated antioxidant activities relative to the control, with the highest antioxidant effect observed at 2 weeks of fermentation of OR 1% BAK. After feeding the OR 1% BAK to thioacetamide-induced liver cirrhosis rats, we observed decreased glutamate oxaloacetate transaminase and glutamate pyruvate transaminase activities and elevated superoxide dismutase activity. CONCLUSIONS: These findings showed that the antioxidant effects of OR BAK and feeding of OR 1% BAK resulted in liver-protective effects against oxidative stress.


Subject(s)
Animals , Antioxidants , Bacterial Load , Fermentation , Glutamic Acid , Hydrogen-Ion Concentration , Lactic Acid , Liver Cirrhosis , Liver , Models, Animal , Oxaloacetic Acid , Oxidative Stress , Phenol , Pyruvic Acid , Rats , Rubus , Superoxide Dismutase
4.
Arq. Ciênc. Vet. Zool. UNIPAR (Online) ; 21(4): 145-146, out-dez. 2018.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-986993

ABSTRACT

Os antioxidantes atuam no combate aos efeitos nocivos provocados pelos radicais livres, proporcionando melhor qualidade do sêmen fresco e criopreservado. As mudanças de temperatura provocadas durante os processos de congelação e descongelação são responsáveis pelos danos aos espermatozoides, alterando sua viabilidade e fertilidade. O estudo dos antioxidantes, os quais constituem a primeira linha de combate às espécies reativas de oxigênio (EROs), para a melhora da qualidade do sêmen criopreservado, torna-se de fundamental importância, para desenvolvimento de protocolos padrões e aplicáveis, uma vez que existem muitas controvérsias em relação ao tipo de molécula antioxidante e às doses, o momento adequado para ser acrescentado e possíveis alterações destes aos meios de criopreservação. Assim, este trabalho tem como objetivo estudar o efeito dos antioxidantes: catalase, α-tocoferol e piruvato de sódio adicionados em meio diluidor comercial para melhorar a viabilidade do sêmen bovino criopreservado. Inicialmente foram utilizados três touros, da raça Brahman, selecionados de acordo com o escore de condição corporal e exame andrológico. Oito ejaculados foram colhidos por eletroejaculação e imediatamente avaliados a motilidade e o vigor espermático. Em seguida, foram diluídos conforme os grupos experimentais em meio Botubov® (Botupharma Biotecnologia Animal) com adição do antioxidante piruvato de sódio nas concentrações de 1,5 µM, 3 µM e 5 µM e em seguida, as amostras foram congeladas. Numa segunda etapa, serão utilizados outros antioxidantes e concentrações, conforme descrito: 1) Diluidor BotuBov®; 2) Diluidor BotuBov® contendo 7% de crioprotetor e catalase nas concentrações de 20, 80 e 200 UI; 3) Diluidor BotuBov® contendo 7% de crioprotetor e α-tocoferol nas concentrações de 50 µM, 100 µM e 150 µM; 4) Diluidor BotuBov® contendo 7% de crioprotetor e piruvato de sódio nas concentrações de 1,5 µM; 3,5 µM e 5 µM. Após a descongelação do sêmen com a utilização do piruvato, as amostras foram analisadas quanto à motilidade total e progressiva e vigor espermático. Verificou-se que a adição de piruvato de sódio na concentração de 1,5 µM proporcionou uma melhora nos parâmetros de motilidade total e vigor espermático, demonstrando os benefícios de seu uso.(AU)


Antioxidants act in fighting the harmful effects caused by free radicals, providing better quality of both fresh and cryopreserved semen. Changes in temperature caused during the freezing and thawing processes are responsible for damages to the sperm, changing their viability and fertility. The study of antioxidants, which constitute the first line of combat against reactive oxygen species (ROS) to improve the quality of cryopreserved semen, is of utmost importance for the development of standard and applicable protocols, since there are many controversies regarding the type and the doses of antioxidant molecules, the timing for its addition and likely changes to the cryopreservation media. This paper aims at studying the effects of catalase, α-tocopherol, and sodium pyruvate when added to commercial diluent medium to improve the viability of cryopreserved bovine semen. Initially, three Brahman bulls were selected according to the body condition score and andrological examination. Eight ejaculates were collected by electroejaculation, with motility and spermatic vigor being immediately assessed. Subsequently, the samples were diluted according to the experimental groups in Botubov® (Botupharma Animal Biotechnology) medium with the addition of sodium pyruvate at concentrations of 1.5 µM, 3 µM and 5 µM and were subsequently frozen. In a second step, other antioxidants and concentrations will be used, as follows: 1) BotuBov® Diluent; 2) BotuBov® diluent containing 7% cryoprotectant and catalase at concentrations of 20, 80 and 200 IU; 3) BotuBov® diluent containing 7% cryoprotectant and α-tocopherol at concentrations of 50 µM, 100 µM and 150 µM; 4) BotuBov® diluent containing 7% cryoprotectant and sodium pyruvate at concentrations of 1.5 µM; 3.5 µM and 5 µM. After thawing the semen with pyruvate, the samples were analyzed for total and progressive motility and spermatic vigor. It was found that the addition of 1.5 µM sodium pyruvate provided an improvement in total motility and sperm vigor parameters, demonstrating the benefits of its use.(AU)


Los antioxidantes actúan en el combate a los efectos nocivos provocados por los radicales libres, proporcionando mejor calidad del semen fresco y criopreservado. Los cambios de temperatura provocados durante los procesos de congelación y descongelación son responsables por los daños a los espermatozoides, alterando su viabilidad y fertilidad. El estudio de los antioxidantes, que constituyen la primera línea de combate a las especies reactivas de oxígeno (ERO), para la mejora de la calidad del semen criopreservado, se hace de fundamental importancia para el desarrollo de protocolos estándares y aplicables, ya que existen muchas controversias en relación al tipo de molécula antioxidante y a las dosis, el momento adecuado para ser añadido y posibles alteraciones de éstos a los medios de criopreservación. Así, este estudio ha tenido como objetivo estudiar el efecto de los antioxidantes: catalasa, α-tocoferol y piruvato de sodio añadidos en medio diluidor comercial para mejorar la viabilidad del semen bovino criopreservado. Inicialmente se utilizaron tres toros, de la raza Brahman, seleccionados de acuerdo con la puntuación de condición corporal y examen andrológico. Ocho eyaculados fueron recogidos por electroejaculación e inmediatamente evaluados la motilidad y el vigor espermático. A continuación, se diluyeron de acuerdo con los grupos experimentales en medio Botubov (Botupharma Biotecnología Animal) con adición de antioxidante piruvato de sodio a concentraciones de 1,5 µM, 3 µM y 5 µM, y luego las muestras se congelaron. En una segunda etapa, se utilizarán otros antioxidantes y concentraciones, según se describe: 1) Diluidor BotuBov®; 2) Diluidor BotuBov® conteniendo 7% de crioprotector y catalasa en las concentraciones de 20, 80 y 200 UI; 3) Diluidor BotuBov® que contiene 7% de crioprotector y α-tocoferol en las concentraciones de 50 µM, 100 µM y 150 µM; 4) Diluidor BotuBov® conteniendo 7% de crioprotector y piruvato de sodio en las concentraciones de 1,5 µM; 3,5 µM y 5 µM. Después de la descongelación del semen con la utilización del piruvato, las muestras fueron analizadas en cuanto a la motilidad total y progresiva y vigor espermático. Se comprobó que la adición de piruvato de sodio en la concentración de 1,5 µM proporcionó una mejora en los parámetros de motilidad total y vigor espermático, demostrando los beneficios de su uso.(AU)


Subject(s)
Animals , Cattle , Cattle/physiology , Pyruvic Acid/chemical synthesis , Semen Analysis/veterinary , Antioxidants/analysis
5.
Braz. j. med. biol. res ; 51(5): e7057, 2018. tab, graf
Article in English | LILACS | ID: biblio-889076

ABSTRACT

The aim of this study was to investigate the effect of lactatemia elevation and glycemia reduction on strenuous swimming performance in fasted rats. Three rats were placed in a swimming tank at the same time. The first rat was removed immediately (control group) and the remaining ones were submitted to a strenuous swimming session. After the second rat was exhausted (Exh group), the third one was immediately removed from the water (Exe group). According to the period of time required for exhaustion, the rats were divided into four groups: low performance (3-7 min), low-intermediary performance (8-12 min), high-intermediary performance (13-17 min), and high performance (18-22 min). All rats were removed from the swimming tanks and immediately killed by decapitation for blood collection or anesthetized for liver perfusion experiments. Blood glucose, lactate, and pyruvate concentrations, blood lactate/pyruvate ratio, and liver lactate uptake and its conversion to glucose were evaluated. Exhaustion in low and low-intermediary performance were better associated with higher lactate/pyruvate ratio. On the other hand, exhaustion in high-intermediary and high performance was better associated with hypoglycemia. Lactate uptake and glucose production from lactate in livers from the Exe and Exh groups were maintained. We concluded that there is a time sequence in the participation of lactate/pyruvate ratio and hypoglycemia in performance during an acute strenuous swimming section in fasted rats. The liver had an important participation in preventing hyperlactatemia and hypoglycemia during swimming through lactate uptake and its conversion to glucose.


Subject(s)
Animals , Male , Rats , Hypoglycemia/physiopathology , Lactic Acid/blood , Liver/physiopathology , Pyruvic Acid/blood , Swimming/physiology , Blood Glucose/analysis , Fasting/physiology , Hypoglycemia/blood , Hypoglycemia/metabolism , Perfusion , Physical Conditioning, Animal/physiology , Rats, Wistar , Time Factors
6.
Article in English | WPRIM | ID: wpr-716320

ABSTRACT

Mitochondrial dysfunction is a hallmark of metabolic diseases such as obesity, type 2 diabetes mellitus, neurodegenerative diseases, and cancers. Dysfunction occurs in part because of altered regulation of the mitochondrial pyruvate dehydrogenase complex (PDC), which acts as a central metabolic node that mediates pyruvate oxidation after glycolysis and fuels the Krebs cycle to meet energy demands. Fine-tuning of PDC activity has been mainly attributed to post-translational modifications of its subunits, including the extensively studied phosphorylation and de-phosphorylation of the E1α subunit of pyruvate dehydrogenase (PDH), modulated by kinases (pyruvate dehydrogenase kinase [PDK] 1-4) and phosphatases (pyruvate dehydrogenase phosphatase [PDP] 1-2), respectively. In addition to phosphorylation, other covalent modifications, including acetylation and succinylation, and changes in metabolite levels via metabolic pathways linked to utilization of glucose, fatty acids, and amino acids, have been identified. In this review, we will summarize the roles of PDC in diverse tissues and how regulation of its activity is affected in various metabolic disorders.


Subject(s)
Acetylation , Amino Acids , Citric Acid Cycle , Diabetes Mellitus, Type 2 , Fatty Acids , Glucose , Glycolysis , Metabolic Diseases , Metabolic Networks and Pathways , Metabolism , Mitochondria , Neurodegenerative Diseases , Obesity , Oxidative Phosphorylation , Oxidoreductases , Phosphoric Monoester Hydrolases , Phosphorylation , Phosphotransferases , Protein Processing, Post-Translational , Pyruvate Dehydrogenase Complex , Pyruvic Acid
7.
Article in English | WPRIM | ID: wpr-716068

ABSTRACT

The purpose of this study was to investigate the relationship between serum tumor markers and dietary intakes in healthy adults to address a nutrition guide for cancer prevention. We analyzed tumor-related markers, carcinoembryonic antigen (CEA), alpha-fetoprotein (AFP), prostate-specific antigen (PSA), and cancer antigen 125 (CA125) in serum and daily food and nutrient intakes using a 24-hour recall method in 23 healthy men and 32 healthy women. The average age was 50.7 years for men and 48.9 years for women. There were no significant differences in biochemical tumor markers and food intake between the men and women except energy intake. A significantly positive correlation was found between serum AFP, a biochemical marker of liver cancer, and serum glutamic oxaloacetic transaminase (GOT) and/or glutamic pyruvate transaminase (GPT) in both men and women. CEA had a significant and negative correlation with energy intake for men and food intake in women. PSA, a biomarker of prostate cancer, was significantly and positively correlated with the intake of animal iron and cholesterol in men. CA125, a biomarker of gynecologic cancers, was significantly and positively correlated with meat intake in women. As this study revealed the significant relationship between biochemical tumor markers and dietary factors, further studies are needed to elucidate the underlying mechanism of this relationship.


Subject(s)
Adult , alpha-Fetoproteins , Animals , Aspartate Aminotransferases , Biomarkers , Biomarkers, Tumor , CA-125 Antigen , Carcinoembryonic Antigen , Cholesterol , Diet , Eating , Energy Intake , Female , Humans , Iron , Liver Neoplasms , Male , Meat , Methods , Prostate-Specific Antigen , Prostatic Neoplasms , Pyruvic Acid
8.
Article in English | WPRIM | ID: wpr-742229

ABSTRACT

Giardia lamblia, an anaerobic, amitochondriate protozoan parasite causes parasitic infection giardiasis in children and young adults. It produces pyruvate, a major metabolic product for its fermentative metabolism. The current study was undertaken to explore the effects of pyruvate as a physiological antioxidant during oxidative stress in Giardia by cysteine-ascorbate deprivation and further investigation upon the hypothesis that oxidative stress due to metabolism was the reason behind the cytotoxicity. We have estimated intracellular reactive oxygen species generation due to cysteine-ascorbate deprivation in Giardia. In the present study, we have examined the effects of extracellular addition of pyruvate, during oxidative stress generated from cysteine-ascorbate deprivation in culture media on DNA damage in Giardia. The intracellular pyruvate concentrations at several time points were measured in the trophozoites during stress. Trophozoites viability under cysteine-ascorbate deprived (CAD) medium in presence and absence of extracellular pyruvate has also been measured. The exogenous addition of a physiologically relevant concentration of pyruvate to trophozoites suspension was shown to attenuate the rate of ROS generation. We have demonstrated that Giardia protects itself from destructive consequences of ROS by maintaining the intracellular pyruvate concentration. Pyruvate recovers Giardia trophozoites from oxidative stress by decreasing the number of DNA breaks that might favor DNA repair.


Subject(s)
Child , Culture Media , DNA Breaks , DNA Damage , DNA Repair , Giardia lamblia , Giardia , Giardiasis , Humans , Metabolism , Oxidative Stress , Parasites , Pyruvic Acid , Reactive Oxygen Species , Trophozoites , Young Adult
9.
Article in English | WPRIM | ID: wpr-108655

ABSTRACT

BACKGROUND/OBJECTIVES: The study was conducted to evaluate the effects of dietary leucine supplementation on mitochondrial biogenesis and energy metabolism in the liver of normal birth weight (NBW) and intrauterine growth-retarded (IUGR) weanling piglets. MATERIALS/METHODS: A total of sixteen pairs of NBW and IUGR piglets from sixteen sows were selected according to their birth weight. At postnatal day 14, all piglets were weaned and fed either a control diet or a leucine-supplemented diet for 21 d. Thereafter, a 2 × 2 factorial experimental design was used. Each treatment consisted of eight replications with one piglet per replication. RESULTS: Compared with NBW piglets, IUGR piglets had a decreased (P < 0.05) hepatic adenosine triphosphate (ATP) content. Also, IUGR piglets exhibited reductions (P < 0.05) in the activities of hepatic mitochondrial pyruvate dehydrogenase (PDH), citrate synthase (CS), α-ketoglutarate dehydrogenase (α-KGDH), malate dehydrogenase (MDH), and complexes I and V, along with decreases (P < 0.05) in the concentration of mitochondrial DNA (mtDNA) and the protein expression of hepatic peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α). Dietary leucine supplementation increased (P < 0.05) the content of ATP, and the activities of CS, α-KGDH, MDH, and complex V in the liver of piglets. Furthermore, compared to those fed a control diet, piglets given a leucine-supplemented diet exhibited increases (P < 0.05) in the mtDNA content and in the mRNA expressions of sirtuin 1, PGC-1α, nuclear respiratory factor 1, mitochondrial transcription factor A, and ATP synthase, H+ transporting, mitochondrial F1 complex, β polypeptide in liver. CONCLUSIONS: Dietary leucine supplementation may exert beneficial effects on mitochondrial biogenesis and energy metabolism in NBW and IUGR weanling piglets.


Subject(s)
Adenosine Triphosphate , Birth Weight , Citrate (si)-Synthase , Diet , DNA, Mitochondrial , Energy Metabolism , Fetal Growth Retardation , Leucine , Liver , Malate Dehydrogenase , Nuclear Respiratory Factor 1 , Organelle Biogenesis , Oxidoreductases , Parturition , Peroxisomes , Pyruvic Acid , Research Design , RNA, Messenger , Sirtuin 1 , Transcription Factors
10.
Article in English | WPRIM | ID: wpr-225907

ABSTRACT

PURPOSE: To investigate the exchange and redistribution of hyperpolarized ¹³C metabolites between different pools by temporally analyzing the relative fraction of dual T₂* components of hyperpolarized ¹³C metabolites. MATERIALS AND METHODS: A dual exponential decay analysis of T₂* is performed for [1-¹³C] pyruvate and [1-¹³C] lactate using nonspatially resolved dynamic ¹³C MR spectroscopy from mice brains with tumors (n = 3) and without (n = 4) tumors. The values of shorter and longer T₂* components are explored when fitted from averaged spectrum and temporal variations of their fractions. RESULTS: The T₂* values were not significantly different between the tumor and control groups, but the fraction of longer T₂* [1-¹³C] lactate components was more than 10% in the tumor group over that of the controls (P < 0.1). The fraction of shorter T₂* components of [1-¹³C] pyruvate showed an increasing tendency while that of the [1-¹³C] lactate was decreasing over time. The slopes of the changing fraction were steeper for the tumor group than the controls, especially for lactate (P < 0.01). In both pyruvate and lactate, the fraction of the shorter T₂* component was always greater than the longer T₂* component over time. CONCLUSIONS: The exchange and redistribution of pyruvate and lactate between different pools was investigated by dual component analysis of the free induction decay signal from hyperpolarized ¹³C experiments. Tumor and control groups showed differences in their fractions rather than the values of longer and shorter T₂* components. Fraction changing dynamics may provide an aspect for extravasation and membrane transport of pyruvate and lactate, and will be useful to determine the appropriate time window for acquisition of hyperpolarized ¹³C images.


Subject(s)
Animals , Brain , Lactic Acid , Magnetic Resonance Spectroscopy , Membranes , Mice , Pyruvic Acid
11.
Article in English | WPRIM | ID: wpr-20676

ABSTRACT

BACKGROUND/OBJECTIVES: Recent living condition improvements, changes in dietary habits, and reductions in physical activity are contributing to an increase in metabolic syndrome symptoms including diabetes and obesity. Through such societal developments, humankind is continuously exposed to metabolic diseases such as diabetes, and the number of the victims is increasing. This study investigated Cordyceps militaris water extract (CMW)-induced glucose uptake in HepG2 cells and the effect of CMW treatment on glucose metabolism. MATERIALS/METHODS: Colorimetric assay kits were used to determine the glucokinase (GK) and pyruvate dehydrogenase (PDH) activities, glucose uptake, and glycogen content. Either RT-PCR or western blot analysis was performed for quantitation of glucose transporter 2 (GLUT2), hepatocyte nuclear factor 1 alpha (HNF-1α), phosphatidylinositol 3-kinase (PI3k), protein kinase B (Akt), phosphorylated AMP-activated protein kinase (pAMPK), phosphoenolpyruvate carboxykinase, GK, PDH, and glycogen synthase kinase 3 beta (GSK-3β) expression levels. The α-glucosidase inhibitory activities of acarbose and CMW were evaluated by absorbance measurement. RESULTS: CMW induced glucose uptake in HepG2 cells by increasing GLUT2 through HNF-1α expression stimulation. Glucose in the cells increased the CMW-induced phosphorylation of AMPK. In turn, glycolysis was stimulated, and glyconeogenesis was inhibited. Furthermore, by studying the mechanism of action of PI3k, Akt, and GSK-3β, and measuring glycogen content, the study confirmed that the glucose was stored in the liver as glycogen. Finally, CMW resulted in a higher level of α-glucosidase inhibitory activity than that from acarbose. CONCLUSION: CMW induced the uptake of glucose into HepG2 cells, as well, it induced metabolism of the absorbed glucose. It is concluded that CMW is a candidate or potential use in diabetes prevention and treatment.


Subject(s)
Acarbose , alpha-Glucosidases , AMP-Activated Protein Kinases , Blotting, Western , Cordyceps , Feeding Behavior , Glucokinase , Glucose Transport Proteins, Facilitative , Glucose , Glycogen , Glycogen Synthase Kinase 3 , Glycolysis , Hep G2 Cells , Hepatocyte Nuclear Factor 1-alpha , Hypoglycemic Agents , Liver , Metabolic Diseases , Metabolism , Motor Activity , Obesity , Oxidoreductases , Phosphatidylinositol 3-Kinase , Phosphoenolpyruvate , Phosphorylation , Proto-Oncogene Proteins c-akt , Pyruvic Acid , Social Conditions , Water
12.
Experimental Neurobiology ; : 295-306, 2017.
Article in English | WPRIM | ID: wpr-18843

ABSTRACT

Glioblastoma multiforme (GBM) is the most common and aggressive form of brain tumors. GBMs, like other tumors, rely relatively less on mitochondrial oxidative phosphorylation (OXPHOS) and utilize more aerobic glycolysis, and this metabolic shift becomes augmented under hypoxia. In the present study, we investigated the physiological significance of altered glucose metabolism and hypoxic adaptation in the GBM cell line U251 and two newly established primary GBMs (GBM28 and GBM37). We found that these three GBMs exhibited differential growth rates under hypoxia compared to those under normoxia. Under normoxia, the basal expressions of HIF1α and the glycolysis-associated genes, PDK1, PDK3, and GLUT1, were relatively low in U251 and GBM28, while their basal expressions were high in GBM37. Under hypoxia, the expressions of these genes were enhanced further in all three GBMs. Treatment with dichloroacetate (DCA), an inhibitor of pyruvate dehydrogenase kinase (PDK), induced cell death in GBM28 and GBM37 maintained under normoxia, whereas DCA effects disappeared under hypoxia, suggesting that hypoxic adaptation dominated DCA effects in these GBMs. In contrast, the inhibition of HIF1α with chrysin suppressed the expression of PDK1, PDK3, and GLUT1 and markedly promoted cell death of all GBMs under both normoxia and hypoxia. Interestingly, however, GBMs treated with chrysin under hypoxia still sustained higher viability than those under normoxia, and chrysin and DCA co-treatment was unable to eliminate this hypoxia-dependent resistance. Together, these results suggest that hypoxic adaptation is critical for maintaining viability of GBMs, and targeting hypoxic adaptation can be an important treatment option for GBMs.


Subject(s)
Hypoxia , Brain Neoplasms , Cell Death , Cell Line , Dichloroacetic Acid , Glioblastoma , Glucose , Glycolysis , Metabolism , Oxidative Phosphorylation , Oxidoreductases , Phosphotransferases , Pyruvic Acid
13.
Yonsei Medical Journal ; : 1312-1323, 2016.
Article in English | WPRIM | ID: wpr-81718

ABSTRACT

PURPOSE: The aim of our study was to explore the relationships between the M2 isoform of pyruvate kinase (PKM2) and the sensitivity of human non-small cell lung cancer (NSCLC) cells to docetaxel in vitro. MATERIALS AND METHODS: With the method of plasmid transfection, we silenced the expression of PKM2 successfully in A549 and H460 cells. Western blotting and real-time PCR were applied to detect PKM2 expression at protein and gene levels. Cell viability was examined by CCK8 assay. Cell cycle distribution and apoptosis were examined by flow cytometry. P21 and Bax were detected. RESULTS: Expression of PKM2 mRNA and protein were significantly decreased by shRNA targeting PKM2. Silencing of PKM2 increased docetaxel sensitivity of human NSCLC A549 and H460 cells in a collaborative manner, resulting in strong suppression of cell viability. The results of flow cytometric assays suggested that knockdown of PKM2 or docetaxel treatment, whether used singly or in combination, blocked the cells in the G2/M phase, which is in consistent with the effect of the two on the expression of p21. Cells with PKM2 silencing were more likely to be induced into apoptosis by docetaxel although knockdown of PKM2 alone can't induce apoptosis significantly, which is in consistent with the effect of the two on Bax expression. CONCLUSION: The results suggest that PKM2 knockdown could serve as a chemosensitizer to docetaxel in non-small lung cancer cells through targeting PKM2, leading to inhibition of cell viability, increase of cell arrest of G2/M phase and apoptosis.


Subject(s)
Apoptosis , Blotting, Western , Carcinoma, Non-Small-Cell Lung , Cell Cycle , Cell Line , Cell Survival , Drug Therapy , Flow Cytometry , Humans , In Vitro Techniques , Lung Neoplasms , Methods , Plasmids , Pyruvate Kinase , Pyruvic Acid , Real-Time Polymerase Chain Reaction , RNA, Messenger , RNA, Small Interfering , Transfection
14.
Article in English | WPRIM | ID: wpr-78634

ABSTRACT

Mitochondria are crucial for maintaining the properties of embryonic stem cells (ESCs) and for regulating their subsequent differentiation into diverse cell lineages, including cardiomyocytes. However, mitochondrial regulators that manage the rate of differentiation or cell fate have been rarely identified. This study aimed to determine the potential mitochondrial factor that controls the differentiation of ESCs into cardiac myocytes. We induced cardiomyocyte differentiation from mouse ESCs (mESCs) and performed microarray assays to assess messenger RNA (mRNA) expression changes at differentiation day 8 (D8) compared with undifferentiated mESCs (D0). Among the differentially expressed genes, Pdp1 expression was significantly decreased (27-fold) on D8 compared to D0, which was accompanied by suppressed mitochondrial indices, including ATP levels, membrane potential, ROS and mitochondrial Ca²⁺. Notably, Pdp1 overexpression significantly enhanced the mitochondrial indices and pyruvate dehydrogenase activity and reduced the expression of cardiac differentiation marker mRNA and the cardiac differentiation rate compared to a mock control. In confirmation of this, a knockdown of the Pdp1 gene promoted the expression of cardiac differentiation marker mRNA and the cardiac differentiation rate. In conclusion, our results suggest that mitochondrial PDP1 is a potential regulator that controls cardiac differentiation at an early differentiation stage in ESCs.


Subject(s)
Adenosine Triphosphate , Animals , Cell Lineage , Embryonic Stem Cells , Membrane Potentials , Mice , Mitochondria , Mouse Embryonic Stem Cells , Myocytes, Cardiac , Oxidoreductases , Pyruvate Dehydrogenase (Lipoamide)-Phosphatase , Pyruvic Acid , RNA, Messenger
15.
Article in English | WPRIM | ID: wpr-100892

ABSTRACT

BACKGROUNG/OBJECTIVES: The study was performed to investigate the effects and mechanisms of action of high maysin corn silk extract on body weight and fat deposition in experimental animals. MATERIALS/METHODS: A total of 30 male C57BL/6J mice, 4-weeks-old, were purchased and divided into three groups by weight using a randomized block design. The normal-fat (NF) group received 7% fat (diet weight basis), the high-fat (HF) group received 25% fat and 0.5% cholesterol, and the high-fat corn silk (HFCS) group received high-fat diet and high maysin corn silk extract at 100 mg/kg body weight through daily oral administration. Body weight and body fat were measured, and mRNA expression levels of proteins involved in adipocyte differentiation, fat accumulation, fat synthesis, lipolysis, and fat oxidation in adipose tissue and the liver were measured. RESULTS: After experimental diet intake for 8 weeks, body weight was significantly lower in the HFCS group compared to the HF group (P < 0.05), and kidney fat and epididymal fat pad weights were significantly lower in the HFCS group compared to the HF group (P < 0.05). In the HFCS group, CCAAT/enhancer binding protein-β, peroxisome proliferator-activated receptor-γ1 (PPAR-γ1), and PPAR-γ2 mRNA expression levels were significantly reduced (P < 0.05) in the epididymal fat pad, whereas cluster of differentiation 36, lipoprotein lipase, acetyl-CoA carboxylase-1, sterol regulatory element binding protein-1c, pyruvate dehydrogenase kinase, isozyme-4, glucose-6-phosphate dehydrogenase, and stearoyl-CoA desaturase-1 mRNA expression levels were significantly decreased in liver and adipose tissues (P < 0.05). In the HFCS group, mRNA expression levels of AMP-activated protein kinase, hormone-sensitive lipase, and carnitine palmitoyltransferase-1 were elevated (P < 0.05). CONCLUSIONS: It can be concluded that high maysin corn silk extract inhibits expression of genes involved in adipocyte differentiation, fat accumulation, and fat synthesis as well as promotes expression of genes involved in lipolysis and fat oxidation, further inhibiting body fat accumulation and body weight elevation in experimental animals.


Subject(s)
Acetyl Coenzyme A , Adipocytes , Adipose Tissue , Administration, Oral , AMP-Activated Protein Kinases , Animals , Body Weight , Carnitine , Cholesterol , Diet , Diet, High-Fat , Glucosephosphate Dehydrogenase , Humans , Kidney , Lipolysis , Lipoprotein Lipase , Liver , Male , Mice , Oxidoreductases , Peroxisomes , Phosphotransferases , Pyruvic Acid , RNA, Messenger , Silk , Sterol Esterase , Weights and Measures , Zea mays
16.
Article in English | WPRIM | ID: wpr-169366

ABSTRACT

Submucosal infiltration and the topical application of epinephrine as a vasoconstrictor produce excellent hemostasis during surgery. The hemodynamic effects of epinephrine have been documented in numerous studies. However, its metabolic effects (especially during surgery) have been seldom recognized clinically. We report two cases of significant metabolic effects (including lactic acidosis and hyperglycemia) as well as hemodynamic effects in healthy patients undergoing orthognathic surgery with general anesthesia. Epinephrine can induce glycolysis and pyruvate generation, which result in lactic acidosis, via β2-adrenergic receptors. Therefore, careful perioperative observation for changes in plasma lactate and glucose levels along with intensive monitoring of vital signs should be carried out when epinephrine is excessively used as a vasoconstrictor during surgery.


Subject(s)
Acidosis, Lactic , Administration, Topical , Anesthesia, General , Anesthesia, Local , Epinephrine , Glucose , Glycolysis , Hemodynamics , Hemostasis , Humans , Lactic Acid , Orthognathic Surgery , Plasma , Pyruvic Acid , Vital Signs
17.
Article in English | WPRIM | ID: wpr-186231

ABSTRACT

Vascular calcification, abnormal mineralization of the vessel wall, is frequently associated with aging, atherosclerosis, diabetes mellitus, and chronic kidney disease. Vascular calcification is a key risk factor for many adverse clinical outcomes, including ischemic cardiac events and subsequent cardiovascular mortality. Vascular calcification was long considered to be a passive degenerative process, but it is now recognized as an active and highly regulated process similar to bone formation. However, despite numerous studies on the pathogenesis of vascular calcification, the mechanisms driving this process remain poorly understood. Pyruvate dehydrogenase kinases (PDKs) play an important role in the regulation of cellular metabolism and mitochondrial function. Recent studies show that PDK4 is an attractive therapeutic target for the treatment of various metabolic diseases. In this review, we summarize our current knowledge regarding the mechanisms of vascular calcification and describe the role of PDK4 in the osteogenic differentiation of vascular smooth muscle cells and development of vascular calcification. Further studies aimed at understanding the molecular mechanisms of vascular calcification will be critical for the development of novel therapeutic strategies.


Subject(s)
Aging , Atherosclerosis , Bone Morphogenetic Proteins , Diabetes Mellitus , Metabolic Diseases , Metabolism , Mitochondria , Mortality , Muscle, Smooth, Vascular , Osteogenesis , Oxidoreductases , Phosphotransferases , Pyruvic Acid , Renal Insufficiency, Chronic , Risk Factors , Vascular Calcification
18.
Article in English | WPRIM | ID: wpr-228228

ABSTRACT

In the previous study, we found that flavonoids and ginsenosides exhibited high eliminate rates of human immunodeficiency virus type 1 (HIV-1) D3-transfected macrophages. Based on these findings, here we synthesized the derivatives of gallic acid, including methyl gallate, methyl 4-O-methyl gallate, methyl 3,4-O-dimethyl gallate, and methyl 3,4,5-O-trimethyl gallate and measured their cellular toxic effects against HIV-1-infected macrophages. Of these, treatment with methyl 4-O-methyl gallate in the presence of lipopolysaccharide (LPS) and cycloheximide (CHX) most effectively eliminated HIV-1-transfected cytoprotective human microglial CHME5 cells and HIV-1-D3-infected human primary macrophages. Furthermore, these strongly inhibited LPS/CHX-induced phosphorylation of phosphoinositide 3-kinase (PI3K), pyruvate dehydrogenase lipoamide kinase isozyme 1 (PDK1), Akt, and glycogen synthase kinase-3β (GSK-3β) in the Tat-transfected cells and HIV-1-D3-infected human primary macrophages. These findings suggest that methyl 4-O-methyl gallate may be a promising candidate for eliminating HIV-1 infected macrophages by blocking PI3K/Akt signaling pathway.


Subject(s)
Cycloheximide , Flavonoids , Gallic Acid , Ginsenosides , Glycogen Synthase , HIV-1 , Humans , Macrophages , Microglia , Oxidoreductases , Phosphorylation , Phosphotransferases , Pyruvic Acid
19.
Article in English | WPRIM | ID: wpr-221980

ABSTRACT

PURPOSE: To develop a technique for quantifying the 13C-metabolites by performing frequency-selective hyperpolarized 13C magnetic resonance spectroscopy (MRS) in vitro which combines simple spectrally-selective excitation with spectrally interleaved acquisition. METHODS: Numerical simulations were performed with varying noise level and K(p) values to compare the quantification accuracies of the proposed and the conventional methods. For in vitro experiments, a spectrally-selective excitation scheme was enabled by narrow-band radiofrequency (RF) excitation pulse implemented into a free-induction decay chemical shift imaging (FIDCSI) sequence. Experiments with LDH / NADH enzyme mixture were performed to validate the effectiveness of the proposed acquisition method. Also, a modified two-site exchange model was formulated for metabolism kinetics quantification with the proposed method. RESULTS: From the simulation results, significant increase of the lactate peak signal to noise ratio (PSNR) was observed. Also, the quantified K(p) value from the dynamic curves were more accurate in the case of the proposed acquisition method compared to the conventional non-selective excitation scheme. In vitro experiment results were in good agreement with the simulation results, also displaying increased PSNR for lactate. Fitting results using the modified two-site exchange model also showed expected results in agreement with the simulations. CONCLUSION: A method for accurate quantification of hyperpolarized pyruvate and the downstream product focused on in vitro experiment was described. By using a narrow-band RF excitation pulse with alternating acquisition, different resonances were selectively excited with a different flip angle for increased PSNR while the hyperpolarized magnetization of the substrate can be minimally perturbed with a low flip angle. Baseline signals from neighboring resonances can be effectively suppressed to accurately quantify the metabolism kinetics.


Subject(s)
Kinetics , Lactic Acid , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Metabolism , NAD , Noise , Pyruvic Acid , Signal-To-Noise Ratio , Spectrum Analysis
20.
Article in Korean | WPRIM | ID: wpr-84876

ABSTRACT

PURPOSE: Skin pH, an indicator of skin health, is maintained by various organic factors, which include lactate, free amino acid (FAA), and free fatty acid (FFA). As skin ages or with illness, skin pH becomes less acidic, and functional food has been developed to maintain the acidic pH of skin. In this study, we determined the dietary effect of green tea extract (GTE) on skin pH of photo-aged mice, as measured by epidermal levels of lactate, FAA, and FFA. The protein expression and activity of lactate dehydrogenase (LDH), an enzyme of pyruvate reduction for lactate generation, was further determined. METHODS: Albino hairless mice were fed a control diet (group UV+) or a diet with 1% GTE (group GTE) in parallel with UV irradiation for 10 weeks. A normal control group was fed a control diet without UV irradiation for 10 weeks (group UV-). RESULTS: Skin pH was higher (less acidic) in group UV+ than in group UV-. In parallel, epidermal levels of lactate and FFA, as well as of LDH protein expression and activity, were reduced in group UV+. Dietary supplementation of GTE (group GTE) reduced skin pH to similar to the level of group UV-, and inversely increased epidermal levels of lactate, LDH protein expression and activity, but not of FFA. Although epidermal levels of FAA were similar in groups UV- and UV+, it was increased in group GTE to a level higher than in group UV-. In further analysis of major FFA, epidermal levels of palmitic acid [16:0], oleic acid [18:1(n-9)], and linoleic acid [18:2(n-6), but not of stearic acid [18:0] in group GTE were similar to or lower than those in group UV+. CONCLUSION: Dietary GTE normalized skin pH with increased levels of lactate and FAA, as well as with increased protein expression and activity of LDH in the epidermis of UVB irradiated hairless mice.


Subject(s)
Animals , Diet , Dietary Supplements , Epidermis , Functional Food , Hydrogen-Ion Concentration , L-Lactate Dehydrogenase , Lactic Acid , Linoleic Acid , Mice , Mice, Hairless , Oleic Acid , Palmitic Acid , Pyruvic Acid , Skin , Tea
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