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1.
Reprod Biol Endocrinol ; 18(1): 58, 2020 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-32493421

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complex endocrine and metabolic disease with unknown pathogenesis. However, the treatment of Diane-35 combined with metformin can improve the endocrine and ovulation of PCOS. In this study, we investigated the effects of Diane-35 combined with metformin (DM) treatment on ovulation and glucose metabolism in a PCOS rat model. METHODS: Sprague Dawley rats were divided into 3 groups, control group, model group (PCOS group) and Diane-35 combined with metformin (PCOS + DM group). The mRNA expression levels were determined by qRT-PCR. The hormone levels were determined by enzyme-linked immunosorbent assay. Immunostaining detected the protein levels of lactate dehydrogenase A (LDH-A), pyruvate kinase isozyme M2 (PKM2) and sirtuin 1 (SIRT1) in the ovarian tissues. TNUEL assay was performed to determine cell apoptosis in the PCOS rats. The metabolites in the ovarian tissues were analyzed by liquid chromatography with tandem mass spectrometry. RESULTS: PCOS rats showed an increased in body weight, levels of luteinizing hormone and testosterone and insulin resistance, which was significantly attenuated by the DM treatment. The DM treatment improved disrupted estrous cycle and increased the granulosa cells of the ovary in the PCOS rats. The decreased proliferation and increased cell apoptosis of granulosa cells in the ovarian tissues of PCOS rats were significantly reversed by the DM treatment. The analysis of metabolics revealed that ATP and lactate levels were significantly decreased in PCOS rats, which was recovered by the DM treatment. Furthermore, the expression of LDH-A, PKM2 and SIRT1 was significantly down-regulated in ovarian tissues of the PCOS rats; while the DM treatment significantly increased the expression of LDH-A, PKM2 and SIRT1 in the ovarian tissues of the PCOS rats. CONCLUSION: In conclusion, our study demonstrated that Diane-35 plus metformin treatment improved the pathological changes in the PCOS rats. Further studies suggest that Diane-35 plus metformin can improve the energy metabolism of the ovary via regulating the glycolysis pathway. The mechanistic studies indicated that the therapeutic effects of Diane-35 plus metformin treatment in the PCOS rats may be associated with the regulation of glycolysis-related mediators including PKM2, LDH-A and SIRT1.


Asunto(s)
Antagonistas de Andrógenos/farmacología , Acetato de Ciproterona/farmacología , Etinilestradiol/farmacología , Glucólisis/efectos de los fármacos , Hipoglucemiantes/farmacología , Metformina/farmacología , Ovulación/efectos de los fármacos , Síndrome del Ovario Poliquístico/metabolismo , Animales , Apoptosis/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Modelos Animales de Enfermedad , Combinación de Medicamentos , Quimioterapia Combinada , Femenino , Resistencia a la Insulina , Lactato Deshidrogenasa 5/efectos de los fármacos , Lactato Deshidrogenasa 5/metabolismo , Hormona Luteinizante/efectos de los fármacos , Hormona Luteinizante/metabolismo , Ovario/efectos de los fármacos , Ovario/metabolismo , Piruvato Quinasa/efectos de los fármacos , Piruvato Quinasa/metabolismo , Ratas , Sirtuina 1/efectos de los fármacos , Sirtuina 1/metabolismo , Testosterona/metabolismo
2.
Blood ; 130(11): 1347-1356, 2017 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-28760888

RESUMEN

Pyruvate kinase (PK) deficiency is a rare genetic disease that causes chronic hemolytic anemia. There are currently no targeted therapies for PK deficiency. Here, we describe the identification and characterization of AG-348, an allosteric activator of PK that is currently in clinical trials for the treatment of PK deficiency. We demonstrate that AG-348 can increase the activity of wild-type and mutant PK enzymes in biochemical assays and in patient red blood cells treated ex vivo. These data illustrate the potential for AG-348 to restore the glycolytic pathway activity in patients with PK deficiency and ultimately lead to clinical benefit.


Asunto(s)
Activadores de Enzimas/farmacología , Activadores de Enzimas/uso terapéutico , Eritrocitos/enzimología , Piruvato Quinasa/deficiencia , Piruvato Quinasa/metabolismo , Quinolinas/farmacología , Quinolinas/uso terapéutico , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico , Anemia Hemolítica Congénita no Esferocítica , Animales , Activación Enzimática/efectos de los fármacos , Activadores de Enzimas/química , Eritrocitos/efectos de los fármacos , Humanos , Cinética , Ratones , Piperazinas , Piruvato Quinasa/efectos de los fármacos , Errores Innatos del Metabolismo del Piruvato , Quinolinas/química , Proteínas Recombinantes/metabolismo , Sulfonamidas/química , Donantes de Tejidos
3.
Microb Pathog ; 134: 103564, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31163248

RESUMEN

Bacterial infections require special care since the indiscriminate use of antibiotics to treat them has been linked to the emergence of resistant strains. In this sense, phytoterapeutic alternatives such as curcumin and its nanocapsules have emerged as a promising supplement in optimizing availability of bioactives and reducing the development of antimicrobial resistance. Thus, the aim of this study was to verify the effects of pure and nanoencapsulated curcumin in the treatment of experimental listeriosis in gerbils regarding many aspects including antibacterial effect, antioxidant mechanisms involved and the energetic metabolism. Four groups were used containing 6 animals each: T0 (control), T1 (infected), T2 (infected and treated with free curcumin - dose of 30 mg/kg/day) and T3 (infected and treated with nanocapsules containing curcumin - a dose of 3 mg/kg/day). Treated animals received curcumin for 6 consecutive days starting 24 h after Listeria monocytogenes infection. All animals were euthanized on the 12th day after L. monocytogenes infection. Quantitative polymerase chain reaction (qPCR) identified L. monocytogenes DNA in the spleens of all animals of the T1 group, as well as T2 (2 out of 6) and T3 (5 out of 6). The weight of the spleens confirmed the infection, since it was larger in the T1 group, differing statistically from T0, and similarly to T2 and T3. Hepatic histopathological examination showed mild infiltration of neutrophils and macrophages, except for the T3 group (only 1/6). In the liver, the pyruvate kinase activity was higher in T1 and T2 compared to T0 and T3. The adenylate kinase activity did not differ between groups. The Na+/K+ATPase activity was lower in T1 group compared to T0 and T3. Lipoperoxidation was lower in the T3 group compared to groups T0, T1 and T2. The antioxidant capacity against peroxyl radicals was higher in T1, T2 and T3 groups compared to T0. In conclusion, free curcumin showed potent antibacterial effects; however, the nanoencapsulated form was able to minimize the effects caused by L. monocytogenes regarding tissue injury, changes on enzymes of the energetic metabolism, in addition to an antioxidant effect against lipoperoxidation.


Asunto(s)
Curcumina/administración & dosificación , Curcumina/uso terapéutico , Listeria monocytogenes/efectos de los fármacos , Listeriosis/tratamiento farmacológico , Listeriosis/veterinaria , Nanocápsulas/química , Adenosina Trifosfatasas , Adenilato Quinasa/efectos de los fármacos , Animales , Antibacterianos/administración & dosificación , Antibacterianos/química , Antibacterianos/uso terapéutico , Antioxidantes/farmacología , Curcumina/química , Suplementos Dietéticos , Modelos Animales de Enfermedad , Gerbillinae , Homeostasis/efectos de los fármacos , Inflamación , Peroxidación de Lípido/efectos de los fármacos , Listeriosis/microbiología , Hígado/patología , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacología , Ácidos Polimetacrílicos/uso terapéutico , Piruvato Quinasa/efectos de los fármacos , ATPasa Intercambiadora de Sodio-Potasio/efectos de los fármacos , Bazo/patología
4.
An Acad Bras Cienc ; 90(1): 99-108, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29236866

RESUMEN

Considering that thiol-containing enzymes like kinases are critical for several metabolic pathways and energy homeostasis, we investigated the effects of cystine dimethyl ester and/or cysteamine administration on kinases crucial for energy metabolism in the kidney of Wistar rats. Animals were injected twice a day with 1.6 µmol/g body weight cystine dimethyl ester and/or 0.26 µmol/g body weight cysteamine from the 16th to the 20th postpartum day and euthanized after 12 hours. Pyruvate kinase, adenylate kinase, creatine kinase activities and thiol/disulfide ratio were determined. Cystine dimethyl ester administration reduced thiol/disulfide ratio and inhibited the kinases activities. Cysteamine administration increased the thiol/disulfide ratio and co-administration with cystine dimethyl ester prevented the inhibition of the enzymes. Regression between the thiol/disulfide ratio, and the kinases activities were significant. These results suggest that redox status may regulate energy metabolism in the rat kidney. If thiol-containing enzymes inhibition and oxidative stress occur in patients with cystinosis, it is possible that lysosomal cystine depletion may not be the only beneficial effect of cysteamine administration, but also its antioxidant and thiol-protector effect.


Asunto(s)
Cisteamina/farmacología , Cistina/análogos & derivados , Disulfuros , Homeostasis/efectos de los fármacos , Riñón/efectos de los fármacos , Compuestos de Sulfhidrilo , Adenilato Quinasa/análisis , Adenilato Quinasa/efectos de los fármacos , Animales , Creatina Quinasa/análisis , Creatina Quinasa/efectos de los fármacos , Cistina/farmacología , Depletores de Cistina/farmacología , Riñón/enzimología , Piruvato Quinasa/análisis , Piruvato Quinasa/efectos de los fármacos , Distribución Aleatoria , Ratas Wistar , Valores de Referencia , Reproducibilidad de los Resultados
5.
FEBS Open Bio ; 14(5): 843-854, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38514913

RESUMEN

Glioblastoma (GBM) is a primary tumor in the central nervous system with poor prognosis. It exhibits elevated glucose uptake and lactate production. This metabolic state of aerobic glycolysis is known as the Warburg effect. N6-isopentenyladenosine (iPA), a natural cytokine modified with an isopentenyl moiety derived from the mevalonate pathway, has well-established anti-tumor activity. It inhibits cell proliferation in glioma cells, inducing cell death by apoptosis and/or necroptosis. In the present study, we found that iPA inhibits aerobic glycolysis in unmodified U87MG cells and in the same cell line engineered to over-express wild-type epidermal growth factor receptor (EGFR) or EGFR variant III (vIII), as well as in a primary GBM4 patient-derived cell line. The detection of glycolysis showed that iPA treatment suppressed ATP and lactate production. We also evaluated the response of iPA treatment in normal human astrocyte primary cells, healthy counterpart cells of the brain. Aerobic glycolysis in treated normal human astrocyte cells did not show significant changes compared to GBM cells. To determine the mechanism of iPA action on aerobic glycolysis, we investigated the expression of certain enzymes involved in this metabolic pathway. We observed that iPA reduced the expression of pyruvate kinase M2 (PKM2), which plays a key role in the regulation of aerobic glycolysis, promoting tumor cell proliferation. The reduction of PKM2 expression is a result of the inhibition of the inhibitor of nuclear factor kappa-B kinase subunit, beta/nuclear factor-kappa B pathway upon iPA treatment. In conclusion, these experimental results show that iPA may inhibit aerobic glycolysis of GBM in stabilized cell lines and primary GBM cells by targeting the expression and activity of PKM2.


Asunto(s)
Glioblastoma , Glucólisis , Isopenteniladenosina , Piruvato Quinasa , Humanos , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Glioblastoma/metabolismo , Glioblastoma/patología , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glucólisis/efectos de los fármacos , Isopenteniladenosina/farmacología , Isopenteniladenosina/metabolismo , Piruvato Quinasa/efectos de los fármacos , Piruvato Quinasa/metabolismo
6.
Cell Transplant ; 30: 9636897211027524, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34263655

RESUMEN

Energy metabolism programming is a hallmark of cancer, and serves as a potent target of cancer therapy. Valproic acid (VPA), a broad Class I histone deacetylases (HDACs) inhibitor, has been used as a therapeutic agent for cancer. However, the detail mechanism about the potential role of VPA on the Warburg effect in breast cancer remains unclear. In this study, we highlight that VPA significantly attenuates the Warburg effect by decreasing the expression of pyruvate kinase M2 isoform (PKM2), leading to inhibited cell proliferation and reduced colony formation in breast cancer MCF-7 and MDA-MB-231 cells. Mechanistically, Warburg effect suppression triggered by VPA was mediated by inactivation of ERK1/2 phosphorylation through reduced HDAC1 expression, resulting in suppressing breast cancer growth. In summary, we uncover a novel mechanism of VPA in regulating the Warburg effect which is essential for developing the effective approach in breast cancer therapy.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Isoformas de Proteínas/efectos de los fármacos , Piruvato Quinasa/efectos de los fármacos , Ácido Valproico/uso terapéutico , Animales , Anticonvulsivantes/farmacología , Proliferación Celular , Femenino , Humanos , Ratones , Ratones Desnudos , Ácido Valproico/farmacología
7.
J Diabetes Investig ; 12(5): 697-709, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33314682

RESUMEN

AIMS/INTRODUCTION: Tubulointerstitial fibrosis is a hallmark of diabetic nephropathy and is associated with an epithelial-to-mesenchymal transition (EMT) program and aberrant glycolysis. Dimeric pyruvate kinase (PK) M2 (PKM2) acts as a key protein kinase in aberrant glycolysis by promoting the accumulation of hypoxia-inducible factor (HIF)-1α, while tetrameric PKM2 functions as a pyruvate kinase in oxidative phosphorylation. The aim of the research is to study the effect of PKM2 tetramer activation on preventing kidney fibrosis via suppression of aberrant glycolysis and the EMT program. MATERIALS AND METHODS: In vivo: Streptozotocin (STZ) was utilized to induce diabetes in 8-week-old CD-1 mice; 4 weeks after diabetes induction, proteinuria-induced kidney fibrosis was developed by intraperitoneal injection of bovine serum albumin (BSA: 0.3 g/30 g BW) for 14 days; The PKM2 activator TEPP-46 was also administered orally simultaneously. In vitro: HK2 cells were co-treated with high-glucose media or/and TGF-ß1 and TEPP46 for 48 h, cellular protein was extracted for evaluation. RESULTS: Diabetic mice developed kidney fibrosis associated with aberrant glycolysis and EMT; BSA injection accelerated kidney fibrosis in both the control and diabetic mice; TEPP-46 rescued the kidney fibrosis. In HK2 cells, TEPP-46 suppressed the EMT program induced by TGF-ß1 and/or high-glucose incubation. TEPP-46-induced PKM2 tetramer formation and PK activity resulted in suppression of HIF-1α and lactate accumulation. Specific siRNA-mediated knockdown of HIF-1α expression diminished high glucose-induced mesenchymal protein levels. CONCLUSION: PKM2 activation could restore the tubular phenotype via suppression of the EMT program and aberrant glycolysis, providing an alternative target to mitigate fibrosis in diabetic kidneys.


Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Nefropatías Diabéticas/prevención & control , Transición Epitelial-Mesenquimal/efectos de los fármacos , Glucólisis/efectos de los fármacos , Piridazinas/farmacología , Pirroles/farmacología , Animales , Diabetes Mellitus Experimental/inducido químicamente , Fibrosis , Subunidad alfa del Factor 1 Inducible por Hipoxia/efectos de los fármacos , Riñón/patología , Ratones , Fosforilación Oxidativa/efectos de los fármacos , Piruvato Quinasa/efectos de los fármacos , Estreptozocina
8.
Biomolecules ; 11(5)2021 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-33925206

RESUMEN

The Warburg effect has been considered a potential therapeutic target to fight against cancer progression. In KRAS mutant cells, PKM2 (pyruvate kinase isozyme M2) is hyper-activated, and it induces GLUT1 expression; therefore, KRAS has been closely involved in the initiation of Warburg metabolism. Although mTOR (mammalian target of rapamycin), a well-known inhibitor of autophagy-dependent survival in physiological conditions, is also activated in KRAS mutants, many recent studies have revealed that autophagy becomes hyper-active in KRAS mutant cancer cells. In the present study, a mathematical model was built containing the main elements of the regulatory network in KRAS mutant cancer cells to explore the further possible therapeutic strategies. Our dynamical analysis suggests that the downregulation of KRAS, mTOR and autophagy are crucial in anti-cancer therapy. PKM2 has been assumed to be the key switch in the stress response mechanism. We predicted that the addition of both pharmacologic ascorbate and chloroquine is able to block both KRAS and mTOR pathways: in this case, no GLUT1 expression is observed, meanwhile autophagy, essential for KRAS mutant cancer cells, is blocked. Corresponding to our system biological analysis, this combined pharmacologic ascorbate and chloroquine treatment in KRAS mutant cancers might be a therapeutic approach in anti-cancer therapies.


Asunto(s)
Cloroquina/farmacología , Neoplasias/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Antineoplásicos/farmacología , Autofagia/efectos de los fármacos , Modelos Teóricos , Neoplasias/tratamiento farmacológico , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Piruvato Quinasa/efectos de los fármacos , Piruvato Quinasa/metabolismo , Transducción de Señal/efectos de los fármacos , Sirolimus/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Efecto Warburg en Oncología/efectos de los fármacos
9.
Trends Endocrinol Metab ; 31(6): 393-395, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32340764

RESUMEN

Angiari et al. recently reported that TEPP-46 induces PKM2 tetramerization, thereby inhibiting its nuclear translocation and suppressing CD4+ T cell activation, T helper (Th)1/Th17 cell development, and experimental autoimmune encephalomyelitis (EAE) development both in vitro and in vivo. Moreover, TEPP-46 suppresses T cell glycolysis. These findings identify PKM2 tetramerization as a potential therapeutic target.


Asunto(s)
Linfocitos T CD4-Positivos/efectos de los fármacos , Encefalomielitis Autoinmune Experimental/etiología , Piridazinas/farmacología , Pirroles/farmacología , Piruvato Quinasa/química , Piruvato Quinasa/efectos de los fármacos , Células TH1/efectos de los fármacos , Células Th17/efectos de los fármacos , Animales , Humanos
10.
Sci Rep ; 8(1): 8323, 2018 05 29.
Artículo en Inglés | MEDLINE | ID: mdl-29844464

RESUMEN

Warburg effect is an emerging hallmark of cancer cells with pyruvate kinase M2 (PKM2) as its key regulator. Curcumin is an extensively-studied anti-cancer compound, however, its role in affecting cancer metabolism remains poorly understood. Herein, we show that curcumin inhibits glucose uptake and lactate production (Warburg effect) in a variety of cancer cell lines by down-regulating PKM2 expression, via inhibition of mTOR-HIF1α axis. Stable PKM2 silencing revealed that PKM2 is required for Warburg effect and proliferation of cancer cells. PKM2 over-expression abrogated the effects of curcumin, demonstrating that inhibition of Warburg effect by curcumin is PKM2-mediated. High PKM2 expression correlated strongly with poor overall survival in cancer, suggesting the requirement of PKM2 in cancer progression. The study unravels novel PKM2-mediated inhibitory effect of curcumin on metabolic capacities of cancer cells. To the best of our knowledge, this is the first study linking curcumin with PKM2-driven cancer glycolysis, thus, providing new perspectives into the mechanism of its anticancer activity.


Asunto(s)
Curcumina/metabolismo , Piruvato Quinasa/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Curcumina/farmacología , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica/genética , Glucólisis/efectos de los fármacos , Células HEK293 , Células HeLa , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Células MCF-7 , Piruvato Quinasa/metabolismo , Serina-Treonina Quinasas TOR/metabolismo
11.
Int J Dev Neurosci ; 23(6): 509-14, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16023820

RESUMEN

Considering that pyruvate kinase activity, a crucial enzyme for glucose metabolism and energy liberation in brain, may be regulated by some amino acids, it is possible that diminution of this enzyme activity may contribute to the brain damage caused by amino acids accumulated in metabolic diseases, such as phenylalanine, tryptophan and cystine. Therefore, the present study was undertaken to investigate the effect of these amino acids on pyruvate kinase activity in the brain cortex of rats. We also investigated the effect of serine and alanine on pyruvate kinase activity in the same tissue. The results suggested that phenylalanine, tryptophan, cystine, alanine, and serine act at the same site on the enzyme, phenylalanine, tryptophan, and cystine causing inhibition, and alanine and serine preventing this effect. Cystine also inhibited the enzyme activity through a different mechanism, possibly acting on the enzyme thiol groups. Considering that this enzyme is a target for amino acids accumulated in some metabolic diseases of amino acid metabolism, it is possible that its inhibition may contribute to the brain damage found in these diseases.


Asunto(s)
Aminoácidos/metabolismo , Corteza Cerebral/enzimología , Metabolismo Energético/fisiología , Piruvato Quinasa/metabolismo , Errores Innatos del Metabolismo de los Aminoácidos/metabolismo , Errores Innatos del Metabolismo de los Aminoácidos/fisiopatología , Aminoácidos/farmacología , Animales , Sitios de Unión/efectos de los fármacos , Sitios de Unión/fisiología , Encefalopatías Metabólicas Innatas/metabolismo , Encefalopatías Metabólicas Innatas/fisiopatología , Corteza Cerebral/efectos de los fármacos , Cistina/metabolismo , Cistina/farmacología , Metabolismo Energético/efectos de los fármacos , Retroalimentación Fisiológica/efectos de los fármacos , Retroalimentación Fisiológica/fisiología , Degeneración Nerviosa/etiología , Degeneración Nerviosa/metabolismo , Degeneración Nerviosa/fisiopatología , Fenilalanina/metabolismo , Fenilalanina/farmacología , Piruvato Quinasa/efectos de los fármacos , Ratas , Ratas Wistar , Serina/metabolismo , Serina/farmacología , Triptófano/metabolismo , Triptófano/farmacología
12.
FEBS Lett ; 403(1): 87-90, 1997 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-9038366

RESUMEN

Resting rat thymocytes partially degrade glucose aerobically to CO2 and H2O and produce reactive peroxide anions. In contrast proliferating cells, due to enhanced induction of glycolytic enzymes, degrade glucose almost completely to lactate thus minimizing the production of reactive oxygen species. In this paper we show that under conditions of oxidative stress the induction of the glycolytic enzymes in cultured rat thymocytes is markedly reduced. Furthermore, transfection assays with a rat hepatoma cell line and Drosophila Schneider cells revealed that reactive oxygen intermediates dramatically decrease the transcriptional activities of the Sp1-dependent aldolase A and pyruvate kinase M2 promoters leading to reduced reporter gene expression. These results indicate that cellular redox changes can regulate gene expression by reversible oxidative inactivation of Sp1 binding.


Asunto(s)
Oxidantes/farmacología , Factor de Transcripción Sp1/metabolismo , Timo/citología , Timo/enzimología , Animales , División Celular/efectos de los fármacos , Células Cultivadas , Concanavalina A/farmacología , ADN/metabolismo , Activación Enzimática/efectos de los fármacos , Femenino , Fructosa-Bifosfato Aldolasa/efectos de los fármacos , Fructosa-Bifosfato Aldolasa/genética , Fructosa-Bifosfato Aldolasa/metabolismo , Regulación de la Expresión Génica , Peróxido de Hidrógeno/farmacología , L-Lactato Deshidrogenasa/efectos de los fármacos , L-Lactato Deshidrogenasa/genética , L-Lactato Deshidrogenasa/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Piruvato Quinasa/efectos de los fármacos , Piruvato Quinasa/genética , Piruvato Quinasa/metabolismo , Ratas , Ratas Wistar , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Factor de Transcripción Sp1/efectos de los fármacos , Timo/efectos de los fármacos , Transcripción Genética/efectos de los fármacos , Transfección
13.
Biotechniques ; 10(5): 656-62, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1910783

RESUMEN

The mass and activity recovery of eight different enzymes (two monomeric, six oligomeric) with molecular masses between 25,000 and 240,000 daltons were tested after HPLC separation on three different HPLC instruments (two with stainless steel and one with titanium flow paths). Most of the tested proteins are known to be sensitive to heavy metal ions. Eight wide pore, ion-exchange columns, two size-exclusion columns and two hydrophobic-interaction columns were used. Both stainless steel and glass column hardware were used in all three separation modes. The elution times were between 8 and 12 minutes. In almost all cases, the activity recovery was between 90% and 100% compared with a control sample incubated in the chromatographic elution buffer for the same time at the same temperature. A severe activity loss (about 30%) was observed with only one ion-exchange column and one enzyme. Neither the column hardware nor the material of the HPLC equipment had any negative effect on the activity recovery of the enzymes tested.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Enzimas/aislamiento & purificación , Alcohol Deshidrogenasa/efectos de los fármacos , Alcohol Deshidrogenasa/aislamiento & purificación , Catalasa/efectos de los fármacos , Catalasa/aislamiento & purificación , Cromatografía en Gel , Cromatografía Líquida de Alta Presión/instrumentación , Cromatografía por Intercambio Iónico , Quimotripsina/efectos de los fármacos , Quimotripsina/aislamiento & purificación , Glucosafosfato Deshidrogenasa/efectos de los fármacos , Glucosafosfato Deshidrogenasa/aislamiento & purificación , Glucosidasas/efectos de los fármacos , Glucosidasas/aislamiento & purificación , Hierro/farmacología , L-Lactato Deshidrogenasa/efectos de los fármacos , L-Lactato Deshidrogenasa/aislamiento & purificación , Piruvato Quinasa/efectos de los fármacos , Piruvato Quinasa/aislamiento & purificación , Factores de Tiempo , Zinc/farmacología
14.
Br J Pharmacol ; 126(2): 467-77, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10077240

RESUMEN

1. Vanadium compounds can mimic actions of insulin through alternative signalling pathways. The effects of three organic vanadium compounds were studied in non-ketotic, streptozotocin-diabetic rats: vanadyl acetylacetonate (VAc), vanadyl 3-ethylacetylacetonate (VEt), and bis(maltolato)oxovanadium (VM). A simple inorganic vanadium salt, vanadyl sulphate (VS) was also studied. 2. Oral administration of the three organic vanadium compounds (125 mg vanadium element 1(-1) in drinking fluids) for up to 3 months induced a faster and larger fall in glycemia (VAc being the most potent) than VS. Glucosuria and tolerance to a glucose load were improved accordingly. 3. Activities and mRNA levels of key glycolytic enzymes (glucokinase and L-type pyruvate kinase) which are suppressed in the diabetic liver, were restored by vanadium treatment. The organic forms showed greater efficacy than VS, especially VAc. 4. VAc rats exhibited the highest levels of plasma or tissue vanadium, most likely due to a greater intestinal absorption. However, VAc retained its potency when given as a single i.p. injection to diabetic rats. Moreover, there was no relationship between plasma or tissue vanadium levels and any parameters of glucose homeostasis and hepatic glucose metabolism. Thus, these data suggest that differences in potency between compounds are due to differences in their insulin-like properties. 5. There was no marked toxicity observed on hepatic or renal function. However, diarrhoea occurred in 50% of rats chronically treated with VS, but not in those receiving the organic compounds. 6. In conclusion, organic vanadium compounds, in particular VAc, correct the hyperglycemia and impaired hepatic glycolysis of diabetic rats more safely and potently than VS. This is not simply due to improved intestinal absorption, indicating more potent insulin-like properties.


Asunto(s)
Glucosa/metabolismo , Ligandos , Compuestos de Vanadio/farmacología , Administración Oral , Animales , Glucemia/efectos de los fármacos , Glucemia/metabolismo , Peso Corporal/efectos de los fármacos , Diabetes Mellitus Experimental/metabolismo , Desinfectantes/farmacología , Glucoquinasa/efectos de los fármacos , Glucoquinasa/genética , Glucoquinasa/metabolismo , Hidroxibutiratos/química , Hidroxibutiratos/farmacología , Hipoglucemiantes/farmacología , Inyecciones Intraperitoneales , Insulina/metabolismo , Islotes Pancreáticos/efectos de los fármacos , Islotes Pancreáticos/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Glucógeno Hepático/metabolismo , Masculino , Músculos/efectos de los fármacos , Músculos/metabolismo , Compuestos Organometálicos/farmacología , Pentanonas/química , Pentanonas/farmacología , Fosfoenolpiruvato Carboxiquinasa (GTP)/efectos de los fármacos , Fosfoenolpiruvato Carboxiquinasa (GTP)/genética , Fosfoenolpiruvato Carboxiquinasa (GTP)/metabolismo , Pironas/química , Pironas/farmacología , Piruvato Quinasa/efectos de los fármacos , Piruvato Quinasa/genética , Piruvato Quinasa/metabolismo , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , Ratas , Ratas Wistar , Factores de Tiempo , Vanadatos/química , Vanadatos/farmacología , Compuestos de Vanadio/química
15.
Mol Cell Endocrinol ; 115(2): 141-8, 1995 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-8824889

RESUMEN

This study tested the hypothesis that 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plays a role in regulating some aspects of metabolism in IMR-90 normal human fetal lung fibroblasts. Among the enzymes studied, only pyruvate kinase showed a significant increase after treatment of confluent-phase cells with 1,25(OH)2D3 at various concentrations (0.1-100 nM range) for 24 h. A parallel increase in lactate output was observed. Steroid specificity was established by the failure of 10 nM levels of 25-hydroxyvitamin D3, estradiol-17 beta and progesterone to affect pyruvate kinase activity. The determination of the time course of [3H]-2-deoxy-D-glucose transport indicated that the hormone did not influence the transmembrane transport system of D-glucose. The addition of the inhibitors cycloheximide and actinomycin D to the culture medium abolished, at least in part, the 1,25(OH)2D3 stimulation of pyruvate kinase activity, suggesting the probable dependence of the hormone effect on cellular RNA and protein synthesis. 1,25(OH)2D3 also affected fibroblast growth and DNA synthesis. Cell number significantly decreased after 2-5 days treatment with 10 nM hormone in comparison with control fibroblasts, and also the incorporation of [3H]thymidine into DNA decreased after treatment of the cells with 1 and 10 nM hormone for 48 h. In conclusion, these data demonstrate that 1,25(OH)2D3 stimulates pyruvate kinase activity in confluent-phase IMR-90 human fibroblasts by a mechanism probably dependent on de novo protein synthesis, and also affects cell growth and DNA synthesis in sub-confluent-phase cells.


Asunto(s)
Calcitriol/farmacología , Inhibidores de Crecimiento/farmacología , Piruvato Quinasa/efectos de los fármacos , Transporte Biológico , Calcitriol/antagonistas & inhibidores , División Celular/efectos de los fármacos , ADN/biosíntesis , Feto , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Glucosa/metabolismo , Inhibidores de Crecimiento/antagonistas & inhibidores , Humanos , Ácido Láctico/metabolismo , Pulmón/citología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Piruvato Quinasa/metabolismo
16.
J Nutr Biochem ; 15(8): 485-92, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15302084

RESUMEN

This study was performed to determine the effects of dietary perilla oil, a n-3 alpha-linolenic acid (ALA) source, on hepatic lipogenesis as a possible mechanism of lowering triacylglycerol (TG) levels. Male Sprague-Dawley rats were trained for a 3-hour feeding protocol and fed one of five semipurified diets as follows: 1% (w/w) corn oil control diet, or one of four diets supplemented with 10% each of beef tallow, corn oil, perilla oil, and fish oil. Two separate experiments were performed to compare the effects of feeding periods, 4 weeks and 4 days. Hepatic and plasma TG levels were decreased in rats fed perilla oil and fish oil diets, compared with corn oil and beef tallow diets. The activities of hepatic lipogenic enzymes such as fatty acid synthase (FAS), glucose-6-phosphate dehydrogenase, and malic enzyme were suppressed in the fish oil, perilla oil, and corn oil-fed groups, and the effect was the most significant in the fish oil-fed group. Also, the activities of glycolytic enzymes, glucokinase, and L-pyruvate kinase showed the similar trend as that of lipogenic enzymes. The activity of FAS, the key regulatory enzyme in lipogenesis, was positively correlated with hepatic and plasma TG levels and reduced significantly in the perilla oil-fed group compared with corn oil-fed group. In addition, the FAS activity was negatively correlated with the hepatic microsomal content of EPA and DHA. In conclusion, suppression of FAS plays a significant role in the hypolipidemic effects observed in rats fed ALA rich perilla oil and these effects were associated with the increase of hepatic microsomal EPA and DHA contents.


Asunto(s)
Ácido Graso Sintasas/efectos de los fármacos , Hígado/enzimología , Aceites de Plantas/farmacología , Triglicéridos/sangre , Ácido alfa-Linolénico/farmacología , Animales , Peso Corporal/efectos de los fármacos , Membrana Celular/química , Membrana Celular/efectos de los fármacos , Aceite de Maíz/farmacología , Grasas de la Dieta/farmacología , Ingestión de Alimentos/efectos de los fármacos , Ácido Graso Sintasas/genética , Ácido Graso Sintasas/metabolismo , Ácidos Grasos/análisis , Aceites de Pescado/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Glucoquinasa/efectos de los fármacos , Glucoquinasa/metabolismo , Hígado/efectos de los fármacos , Masculino , Piruvato Quinasa/efectos de los fármacos , Piruvato Quinasa/metabolismo , Ratas , Ratas Sprague-Dawley
17.
Life Sci ; 50(23): PL203-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1317934

RESUMEN

The effects of two representative sulfonylureas, tolbutamide and glyburide, on pyruvate kinase (PK) flux were examined in fasted rat hepatocytes. PK flux was estimated by trapping 14C from NaH14CO3 in a 2 mM lactate pool, accounting for any incomplete trapping by parallel incubations with L-[1-14C]alanine. Glyburide (20 microM) and tolbutamide (1 mM) decreased glucose formation by 34.9% and 54.8%, respectively, from 2 mM lactate. This decrease in glucose formation was associated with a proportional decrease in pyruvate carboxylase (PCOX) flux (32.7% and 50.5%, respectively). Under these conditions, no net change in PK flux was observed. When hepatocytes were preincubated with lactate and/or sulfonylurea addition for 30 min prior to radiolabeling with NaH14CO3, the metabolic state of the cells changed markedly. Glyburide produced a 34.6% decrease in glucose formation and a 31.3% decrease in PCOX flux, but no change in PK flux. In contrast, tolbutamide decreased glucose formation by 12.5% and increased PK flux by 53.2%, but no change in PCOX flux was observed. Such an increase in PK flux may be linked to tolbutamide-mediated increases in fructose-1,6-bisphosphate (F16P) via fructose-2,6-bisphosphate (F26P). These findings demonstrate that tolbutamide and glyburide decrease hepatic glucose production through various alterations in carbohydrate metabolism, depending upon the metabolic state of the cell. In addition, F26P may play a larger role in the hypoglycemic mechanism of action of tolbutamide than glyburide, since pyruvate carboxylase accounted for most of the decrease in glucose formation observed with glyburide and because preincubation with tolbutamide resulted in an activation of PK.


Asunto(s)
Gliburida/farmacología , Hígado/enzimología , Piruvato Quinasa/metabolismo , Tolbutamida/farmacología , Animales , Bicarbonatos/metabolismo , Radioisótopos de Carbono , Glucosa/biosíntesis , Lactatos/metabolismo , Lactatos/farmacología , Hígado/citología , Hígado/efectos de los fármacos , Masculino , Piruvato Quinasa/efectos de los fármacos , Ratas , Ratas Endogámicas , Sensibilidad y Especificidad , Sodio/metabolismo , Bicarbonato de Sodio , Compuestos de Sulfonilurea/farmacología , Factores de Tiempo
18.
Comp Biochem Physiol B Biochem Mol Biol ; 134(3): 425-33, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12628374

RESUMEN

Pyruvate kinase type M(2) from Morris hepatoma 7777 tumour cell nuclei and cytosol, in contrast to types L and M(2) from nuclei and cytosol of normal rat liver, shows the histone H(1) kinase activity. Moreover, in the presence of L-cysteine and without ADP it converts 2-phosphoenolpyruvate (PEP) to pyruvate while in the presence of L-arginine or L-histidine does not. L-Cysteine markedly stimulates the activity of histone H(1) kinase transferring a phosphate group from PEP to, as results suggested, the epsilon -amino group of L-lysine of histone H(1). This, L-cysteine which is known to inhibit the activity of pyruvate kinase type M(2) from neoplastic cells transfering a phosphate from PEP to ADP, can act as a control factor champing the direction of enzymatic reaction in cancer cells.


Asunto(s)
Neoplasias Hepáticas Experimentales/enzimología , Hígado/enzimología , Piruvato Quinasa/metabolismo , Adenosina Trifosfato/farmacología , Animales , Arginina/farmacología , Fraccionamiento Celular , Cromatina/aislamiento & purificación , Cromatina/metabolismo , Cisteína/farmacología , Citosol/enzimología , Electroforesis en Gel de Poliacrilamida , Inhibidores Enzimáticos/farmacología , Histidina/farmacología , Isoenzimas/química , Isoenzimas/efectos de los fármacos , Isoenzimas/metabolismo , Fosfoenolpiruvato/farmacología , Piruvato Quinasa/química , Piruvato Quinasa/efectos de los fármacos , Ratas , Ratas Endogámicas BUF
19.
Artículo en Inglés | MEDLINE | ID: mdl-9640602

RESUMEN

In Thailand, the most common cause of chronic hemolytic anemia is thalassemia hemoglobinopathy. We report here a 10-year-old girl with pyruvate kinase (PK) deficiency who was initially diagnosed to have Hb H disease, like her sister. The patient had a history of neonatal jaundice which required blood exchange transfusion twice and phototherapy. She became anemic and regular blood transfusion was required since the age of 2 1/2 months. She was very anemic compared to her sister and was transfusion dependent. Besides, she never had red cell inclusion bodies, thus re-evaluation was performed. The diagnosis of red cell pyruvate kinase deficiency and the exclusion of Hb H disease was achieved after cessation of blood transfusion for 3 months. The family study also confirmed the diagnosis. The patient is now on high transfusion and iron chelation. She is doing well with mild splenomegaly.


Asunto(s)
Piruvato Quinasa/efectos de los fármacos , Talasemia alfa/epidemiología , Niño , Eritrocitos/enzimología , Familia , Femenino , Humanos , Tailandia/epidemiología
20.
Indian J Exp Biol ; 30(1): 8-11, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1387111

RESUMEN

Effects of prolactin (PRL), bromocriptine (Br), testosterone propionate (TP), dihydrotestosterone (DHT) and the combinations of these androgens with PRL/Br on the specific activities of caudal and cranial prostatic cellular enzymes involved in carbohydrate metabolism in castrated mature bonnet monkeys have been studied. Castration decreased all the enzymes studied such as hexokinase (HK), 6-phosphofructokinase (6-PFK), glyceraldehyde-3-phosphate dehydrogenase (G-3-PD), pyruvate kinase (PK), glucose-6-phosphate dehydrogenase (G-6-PD) and 6-phosphogluconate dehydrogenase (6-PGD) in the cranial and caudal prostates. PRL elevated the activities of all the enzymes above normal except G-3-PD of cranial lobe. In the caudal lobe, PRL brought back the activities of HK, PFK, PK, G-6-PD to normal and 6-PGD above normal except G-3-PD. TP/DHT treatment increased all the enzymes in both the lobes. PRL given along with TP/DHT further enhanced the androgen action with regard to HK, PK, G-6-PD and 6-PGD of cranial and PFK, G-3-PD, PK, G-6-PD and 6-PGD of caudal lobe. Br treatment did not produce any alteration of these enzymes in both the lobes. In the cranial lobe, during Br+TP/DHT treatment, the stimulating effects of androgen were unaffected on all the enzymes except PK. On the other hand in the caudal, the stimulatory effects of androgens were affected and the activities of HK, PFK, PK and 6-PGD were significantly decreased. The present results suggest that PRL has a direct as well as a synergistic action with androgens on enzymes of EMP and HMP shunt in the prostates of monkeys.


Asunto(s)
Andrógenos/farmacología , Metabolismo de los Hidratos de Carbono , Prolactina/farmacología , Próstata/enzimología , Animales , Castración , Glucosafosfato Deshidrogenasa/efectos de los fármacos , Gliceraldehído-3-Fosfato Deshidrogenasas/efectos de los fármacos , Hexoquinasa/efectos de los fármacos , Macaca radiata , Masculino , Fosfofructoquinasa-1/efectos de los fármacos , Fosfogluconato Deshidrogenasa/efectos de los fármacos , Próstata/efectos de los fármacos , Próstata/metabolismo , Piruvato Quinasa/efectos de los fármacos
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