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1.
Planta ; 259(5): 102, 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38549005

RESUMEN

MAIN CONCLUSION: Hydroxy(phenyl)pyruvic acid reductase from Actaea racemosa catalyzes dual reactions in reducing 4-hydroxyphenylpyruvic acid as well as ß-hydroxypyruvic acid. It thus qualifies to be part of fukinolic and cimicifugic acid biosynthesis and also photorespiration. The accumulation of fukinolic acid and cimicifugic acids is mainly restricted to Actaea racemosa (Ranunculaceae) and other species of the genus Actaea/Cimicifuga. Cimicifugic and fukinolic acids are composed of a hydroxycinnamic acid part esterified with a benzyltartaric acid moiety. The biosynthesis of the latter is unclear. We isolated cDNA encoding a hydroxy(phenyl)pyruvic acid reductase (GenBank OR393286) from suspension-cultured material of A. racemosa (ArH(P)PR) and expressed it in E. coli for protein production. The heterologously synthesized enzyme had a mass of 36.51 kDa and catalyzed the NAD(P)H-dependent reduction of 4-hydroxyphenylpyruvic acid to 4-hydroxyphenyllactic acid or ß-hydroxypyruvic acid to glyceric acid, respectively. The optimal temperature was at 38 °C and the pH optimum at pH 7.5. NADPH is the preferred cosubstrate (Km 23 ± 4 µM). Several substrates are accepted by ArH(P)PR with ß-hydroxypyruvic acid (Km 0.26 ± 0.12 mM) followed by 4-hydroxyphenylpyruvic acid (Km 1.13 ± 0.12 mM) as the best ones. Thus, ArH(P)PR has properties of ß-hydroxypyruvic acid reductase (involved in photorespiration) as well as hydroxyphenylpyruvic acid reductase (possibly involved in benzyltartaric acid formation).


Asunto(s)
Ácidos Cafeicos , Cimicifuga , Fenilacetatos , Ácidos Fenilpirúvicos , Piruvatos , Cimicifuga/química , Ácido Pirúvico , Oxidorreductasas , Escherichia coli/genética , Extractos Vegetales
2.
J Biol Chem ; 299(12): 105375, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37865313

RESUMEN

Pyruvate dehydrogenase (PDH) is the rate-limiting enzyme for glucose oxidation that links glycolysis-derived pyruvate with the tricarboxylic acid (TCA) cycle. Although skeletal muscle is a significant site for glucose oxidation and is closely linked with metabolic flexibility, the importance of muscle PDH during rest and exercise has yet to be fully elucidated. Here, we demonstrate that mice with muscle-specific deletion of PDH exhibit rapid weight loss and suffer from severe lactic acidosis, ultimately leading to early mortality under low-fat diet provision. Furthermore, loss of muscle PDH induces adaptive anaplerotic compensation by increasing pyruvate-alanine cycling and glutaminolysis. Interestingly, high-fat diet supplementation effectively abolishes early mortality and rescues the overt metabolic phenotype induced by muscle PDH deficiency. Despite increased reliance on fatty acid oxidation during high-fat diet provision, loss of muscle PDH worsens exercise performance and induces lactic acidosis. These observations illustrate the importance of muscle PDH in maintaining metabolic flexibility and preventing the development of metabolic disorders.


Asunto(s)
Acidosis Láctica , Alanina , Músculo Esquelético , Complejo Piruvato Deshidrogenasa , Ácido Pirúvico , Animales , Ratones , Acidosis Láctica/fisiopatología , Glucosa/metabolismo , Músculo Esquelético/metabolismo , Complejo Piruvato Deshidrogenasa/genética , Complejo Piruvato Deshidrogenasa/metabolismo , Ácido Pirúvico/metabolismo , Glutamina/metabolismo , Alanina/metabolismo , Eliminación de Gen , Dieta , Mortalidad Prematura
3.
J Tradit Chin Med ; 43(5): 1026-1033, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37679991

RESUMEN

OBJECTIVE: To investigate the effect of - Xiaoyi Yusi decoction (XYYSD, ), a Traditional Chinese Medicine (TCM), on fertilization and embryo transfer (IVF-ET) in patients with endometriosis, and to study the mechanism underpinning the action. METHODS: Women who underwent IVF-ET were divided into three groups by simple randomization: the treatment ( 32; with TCM treatment), patient (28; with endometriosis alone), and control (33; with male factor alone) groups. The luteal phase short-acting gonadotropin-releasing hormone agonist prolonged protocol was used in all three groups. To compare the changes in TCM scores and reproductive outcomes before and after TCM intervention in patients with endometriosis, partial least-squares discriminant analysis was used to analyze the follicular fluid samples of each group and screen and compare metabolites using the MetaboAnalyst software. RESULTS: The clinical data indicated that following TCM intervention, kidney deficiency and blood stasis symptom patterns improved dramatically in patients with endometriosis and that their clinical pregnancy rate increased significantly (71.9% 57.1%, 0.05). Metabolomics showed that the two groups of samples were separated before and after TCM intervention. After TCM intervention, the intervention group was close to the control group, indicating that the TCM had a certain effect. Pathway analysis revealed that after TCM intervention, the metabolism of glycerin phospholipid, pyruvate, and citric acid was regulated. CONCLUSIONS: Through the pyruvate and glycerophospholipid metabolism pathways and tricarboxylic acid cycle, the TCM XYYSD successfully improved kidney deficiency and blood stasis symptom pattern, as well as the clinical reproductive outcomes of patients with endometriosis-related infertility.


Asunto(s)
Endometriosis , Embarazo , Humanos , Femenino , Masculino , Endometriosis/tratamiento farmacológico , Ácido Pirúvico , Ácido Cítrico , Transferencia de Embrión , Fertilización
4.
Physiol Res ; 72(3): 403-414, 2023 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-37449752

RESUMEN

Pyruvate carboxylase (PC) is a mitochondrial, biotin-containing enzyme catalyzing the ATP-dependent synthesis of oxaloacetate from pyruvate and bicarbonate, with a critical anaplerotic role in sustaining the brain metabolism. Based on the studies performed on animal models, PC expression was assigned to be glia-specific. To study PC distribution among human neural cells, we probed the cultured human astrocytes and brain sections with antibodies against PC. Additionally, we tested the importance of PC for the viability of cultured human astrocytes by applying the PC inhibitor 3-chloropropane-1,2-diol (CPD). Our results establish the expression of PC in mitochondria of human astrocytes in culture and brain tissue and also into a subpopulation of the neurons in situ. CPD negatively affected the viability of astrocytes in culture, which could be partially reversed by supplementing media with malate, 2-oxoglutarate, citrate, or pyruvate. The provided data estimates PC expression in human astrocytes and neurons in human brain parenchyma. Furthermore, the enzymatic activity of PC is vital for sustaining the viability of cultured astrocytes.


Asunto(s)
Astrocitos , Piruvato Carboxilasa , Animales , Humanos , Piruvato Carboxilasa/metabolismo , Astrocitos/metabolismo , Ácido Pirúvico/metabolismo , Encéfalo/metabolismo , Neuronas/metabolismo
5.
J Cereb Blood Flow Metab ; 43(10): 1685-1701, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37157814

RESUMEN

How to optimise glucose metabolism in the traumatised human brain remains unclear, including whether injured brain can metabolise additional glucose when supplied. We studied the effect of microdialysis-delivered 1,2-13C2 glucose at 4 and 8 mmol/L on brain extracellular chemistry using bedside ISCUSflex, and the fate of the 13C label in the 8 mmol/L group using high-resolution NMR of recovered microdialysates, in 20 patients. Compared with unsupplemented perfusion, 4 mmol/L glucose increased extracellular concentrations of pyruvate (17%, p = 0.04) and lactate (19%, p = 0.01), with a small increase in lactate/pyruvate ratio (5%, p = 0.007). Perfusion with 8 mmol/L glucose did not significantly influence extracellular chemistry measured with ISCUSflex, compared to unsupplemented perfusion. These extracellular chemistry changes appeared influenced by the underlying metabolic states of patients' traumatised brains, and the presence of relative neuroglycopaenia. Despite abundant 13C glucose supplementation, NMR revealed only 16.7% 13C enrichment of recovered extracellular lactate; the majority being glycolytic in origin. Furthermore, no 13C enrichment of TCA cycle-derived extracellular glutamine was detected. These findings indicate that a large proportion of extracellular lactate does not originate from local glucose metabolism, and taken together with our earlier studies, suggest that extracellular lactate is an important transitional step in the brain's production of glutamine.


Asunto(s)
Glucosa , Glutamina , Humanos , Glucosa/metabolismo , Glutamina/metabolismo , Encéfalo/metabolismo , Microdiálisis , Ácido Láctico/metabolismo , Ácido Pirúvico/metabolismo , Suplementos Dietéticos
6.
Metab Eng ; 77: 219-230, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37031949

RESUMEN

Malonyl-CoA is a central precursor for biosynthesis of a wide range of complex secondary metabolites. The development of platform strains with increased malonyl-CoA supply can contribute to the efficient production of secondary metabolites, especially if such strains exhibit high tolerance towards these chemicals. In this study, Pseudomonas taiwanensis VLB120 was engineered for increased malonyl-CoA availability to produce bacterial and plant-derived polyketides. A multi-target metabolic engineering strategy focusing on decreasing the malonyl-CoA drain and increasing malonyl-CoA precursor availability, led to an increased production of various malonyl-CoA-derived products, including pinosylvin, resveratrol and flaviolin. The production of flaviolin, a molecule deriving from five malonyl-CoA molecules, was doubled compared to the parental strain by this malonyl-CoA increasing strategy. Additionally, the engineered platform strain enabled production of up to 84 mg L-1 resveratrol from supplemented p-coumarate. One key finding of this study was that acetyl-CoA carboxylase overexpression majorly contributed to an increased malonyl-CoA availability for polyketide production in dependence on the used strain-background and whether downstream fatty acid synthesis was impaired, reflecting its complexity in metabolism. Hence, malonyl-CoA availability is primarily determined by competition of the production pathway with downstream fatty acid synthesis, while supply reactions are of secondary importance for compounds that derive directly from malonyl-CoA in Pseudomonas.


Asunto(s)
Malonil Coenzima A , Policétidos , Pseudomonas , Ácidos Grasos/metabolismo , Malonil Coenzima A/metabolismo , Policétidos/metabolismo , Pseudomonas/clasificación , Pseudomonas/genética , Pseudomonas/metabolismo , Resveratrol/metabolismo , Metabolismo Secundario , Estilbenos/metabolismo , Ácidos Cumáricos/metabolismo , Fenilalanina/metabolismo , Genoma Bacteriano/genética , Eliminación de Secuencia , Acetilcoenzima A/metabolismo , Citrato (si)-Sintasa/metabolismo , Ácido Pirúvico/metabolismo , Fitoalexinas/metabolismo , Naftoquinonas/metabolismo
7.
Biotechnol J ; 18(6): e2200243, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36892270

RESUMEN

Hydrolysates are used as media supplements although their role is not well characterized. In this study, cottonseed hydrolysates, which contained peptides and galactose as supplemental substrates, were added to Chinese hamster ovary (CHO) batch cultures, enhancing cell growth, immunoglobulin (IgG) titers, and productivities. Extracellular metabolomics coupled with tandem mass tag (TMT) proteomics revealed metabolic and proteomic changes in cottonseed-supplemented cultures. Shifts in production and consumption dynamics of glucose, glutamine, lactate, pyruvate, serine, glycine, glutamate, and aspartate suggest changes in tricarboxylic acid (TCA) and glycolysis metabolism following hydrolysate inputs. Quantitative proteomics revealed 5521 proteins and numerous changes in relative abundance of proteins related to growth, metabolism, oxidative stress, protein productivity, and apoptosis/cell death at day 5 and day 6. Differential abundance of amino acid transporter proteins and catabolism enzymes such as branched-chain-amino-acid aminotransferase (BCAT)1 and fumarylacetoacetase (FAH) can alter availability and utilization of several amino acids. Also, pathways involved in growth including the polyamine biosynthesis through higher ornithine decarboxylase (ODC1) abundance and hippo signaling were upregulated and downregulated, respectively. Central metabolism rewiring was indicated by glyceraldehyde-3-phosphate dehydrogenase (GAPDH) downregulation, which corresponded with re-uptake of secreted lactate in the cottonseed-supplemented cultures. Overall, cottonseed hydrolysate supplementation modified culture performance by altering cellular activities critical to growth and protein productivity including metabolism, transport, mitosis, transcription, translation, protein processing, and apoptosis. HIGHLIGHTS: Cottonseed hydrolysate, as a medium additive, enhances Chinese hamster ovary (CHO) cell culture performance. Metabolite profiling and tandem mass tag (TMT) proteomics characterize its impact on CHO cells. Rewired nutrient utilization is observed via glycolysis, amino acid, and polyamine metabolism. Hippo signaling pathway impacts cell growth in the presence of cottonseed hydrolysate.


Asunto(s)
Aceite de Semillas de Algodón , Proteómica , Cricetinae , Animales , Cricetulus , Células CHO , Técnicas de Cultivo Celular por Lotes , Ácido Láctico/metabolismo , Ácido Pirúvico , Aminoácidos/metabolismo , Suplementos Dietéticos , Poliaminas
8.
Int J Mol Sci ; 24(2)2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36675238

RESUMEN

The most frequent alterations in plasma amino acid concentrations in type 1 and type 2 diabetes are decreased L-serine and increased branched-chain amino acid (BCAA; valine, leucine, and isoleucine) levels. The likely cause of L-serine deficiency is decreased synthesis of 3-phosphoglycerate, the main endogenous precursor of L-serine, due to impaired glycolysis. The BCAA levels increase due to decreased supply of pyruvate and oxaloacetate from glycolysis, enhanced supply of NADH + H+ from beta-oxidation, and subsequent decrease in the flux through the citric acid cycle in muscles. These alterations decrease the supply of α-ketoglutarate for BCAA transamination and the activity of branched-chain keto acid dehydrogenase, the rate-limiting enzyme in BCAA catabolism. L-serine deficiency contributes to decreased synthesis of phospholipids and increased synthesis of deoxysphinganines, which play a role in diabetic neuropathy, impaired homocysteine disposal, and glycine deficiency. Enhanced BCAA levels contribute to increased levels of aromatic amino acids (phenylalanine, tyrosine, and tryptophan), insulin resistance, and accumulation of various metabolites, whose influence on diabetes progression is not clear. It is concluded that amino acid concentrations should be monitored in patients with diabetes, and systematic investigation is needed to examine the effects of L-serine and glycine supplementation on diabetes progression when these amino acids are decreased.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Aminoácidos de Cadena Ramificada/metabolismo , Aminoácidos/metabolismo , Ácido Pirúvico , Glucólisis , Glicina/metabolismo , Serina/metabolismo
9.
Front Immunol ; 13: 1028953, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36466902

RESUMEN

Inflammatory Bowel Disease (IBD) is characterized by a loss of intestinal barrier function caused by an aberrant interaction between the immune response and the gut microbiota. In IBD, imbalance in cholesterol homeostasis and mitochondrial bioenergetics have been identified as essential events for activating the inflammasome-mediated response. Mitochondrial alterations, such as reduced respiratory complex activities and reduced production of tricarboxylic acid (TCA) cycle intermediates (e.g., citric acid, fumarate, isocitric acid, malate, pyruvate, and succinate) have been described in in vitro and clinical studies. Under inflammatory conditions, mitochondrial architecture in intestinal epithelial cells is dysmorphic, with cristae destruction and high dynamin-related protein 1 (DRP1)-dependent fission. Likewise, these alterations in mitochondrial morphology and bioenergetics promote metabolic shifts towards glycolysis and down-regulation of antioxidant Nuclear erythroid 2-related factor 2 (Nrf2)/Peroxisome proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) signaling. Although the mechanisms underlying the mitochondrial dysfunction during mucosal inflammation are not fully understood at present, metabolic intermediates and cholesterol may act as signals activating the NLRP3 inflammasome in IBD. Notably, dietary phytochemicals exhibit protective effects against cholesterol imbalance and mitochondrial function alterations to maintain gastrointestinal mucosal renewal in vitro and in vivo conditions. Here, we discuss the role of cholesterol and mitochondrial metabolism in IBD, highlighting the therapeutic potential of dietary phytochemicals, restoring intestinal metabolism and function.


Asunto(s)
Inflamasomas , Enfermedades Inflamatorias del Intestino , Humanos , Mitocondrias , Colesterol , Enfermedad Crónica , Glucólisis , Ácido Pirúvico
10.
Plant Biotechnol J ; 20(12): 2406-2417, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36056567

RESUMEN

Bile acid: sodium symporter family protein 2 (BASS2) is a sodium-dependent pyruvate transporter, which transports pyruvate from cytosol into plastid in plants. In this study, we investigated the function of chloroplast envelope membrane-localized BnaBASS2 in seed metabolism and seed oil accumulation of Brassica napus (B. napus). Four BASS2 genes were identified in the genome of B. napus. BnaA05.BASS2 was overexpressed while BnaA05.BASS2 and BnaC04.BASS2-1 were mutated by CRISPR in B. napus. Metabolite analysis revealed that the manipulation of BnaBASS2 caused significant changes in glycolysis-, fatty acid synthesis-, and energy-related metabolites in the chloroplasts of 31 day-after-flowering (DAF) seeds. The analysis of fatty acids and lipids in developing seeds showed that BnaBASS2 could affect lipid metabolism and oil accumulation in developing seeds. Moreover, the overexpression (OE) of BnaA05.BASS2 could promote the expression level of multiple genes involved in the synthesis of oil and the formation of oil body during seed development. Disruption of BnaA05.BASS2 and BnaC04.BASS2-1 resulted in decreasing the seed oil content (SOC) by 2.8%-5.0%, while OE of BnaA05.BASS2 significantly promoted the SOC by 1.4%-3.4%. Together, our results suggest that BnaBASS2 is a potential target gene for breeding B. napus with high SOC.


Asunto(s)
Brassica napus , Brassica napus/genética , Transportadores de Ácidos Monocarboxílicos , Fitomejoramiento , Semillas/genética , Ácido Pirúvico , Aceites de Plantas
11.
J Magn Reson ; 343: 107286, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36075133

RESUMEN

PURPOSE: We constructed a 13C/31P surface coil at 3 T for studying cancer metabolism and bioenergetics. In a single scan session, hyperpolarized 13C-pyruvate MRS and 31P MRS was carried out for a healthy rat brain. METHODS: All experiments were carried out at 3 Tesla. The multinuclear surface coil was designed as two coplanar loops each tuned to either the 13C or 31P operating frequency with an LCC trap on the 13C loop. A commercial volume proton coil was used for anatomical localization and B0 shimming. Single tuned coils operating at either the 13C or 31P frequency were built to evaluate the relative performance of the multinuclear coil. Coil performance metrics consisted of measuring Q factor ratio, calculating system input power using a single-pulse acquisition, and acquiring SNR and flip angle maps using 2D CSI sequences. To observe in vivo spectra, a bolus of hyperpolarized [1-13C] pyruvate was administered via tail vein. In vivo13C and endogenous 31P spectra were obtained in a single scan session using 1D slice selective acquisitions. RESULTS: When compared with single tuned surface coils, the multinuclear coil performance showed a decrease in Q factor ratio, SNR, and transmit efficiency. Flip angle maps showed adequate flip angles within the phantom when the transmit voltage was set using an external phantom. Results show good detection of 13C labeled lactate, alanine, and bicarbonate in addition to ATP from 31P MRS. CONCLUSIONS: The coil enables obtaining complementary information within a scan session, thus reducing the number of trials and minimizing biological variability for studies of metabolism and bioenergetics.


Asunto(s)
Imagen por Resonancia Magnética , Protones , Animales , Ratas , Roedores/metabolismo , Bicarbonatos , Encéfalo/diagnóstico por imagen , Encéfalo/metabolismo , Fantasmas de Imagen , Ácido Pirúvico/metabolismo , Lactatos , Alanina , Adenosina Trifosfato , Diseño de Equipo
12.
Molecules ; 27(18)2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36144527

RESUMEN

Globally, cancer is the second leading cause of mortality and morbidity. The growth and development of cancer are extremely complex. It is caused by a variety of pathways and involves various types of enzymes. Pyruvate kinase M2 (PKM2) is an isoform of pyruvate kinase, that catalyses the last steps of glycolysis to produce energy. PKM2 is relatively more expressed in tumour cells where it tends to exist in a dimer form. Various medicinal plants are available that contain a variety of micronutrients to combat against different cancers. The phytocompounds of the olive tree (Olea europaea) leaves play an important role in inhibiting the proliferation of several cancers. In this study, the phytocompounds of olive leaf extract (OLE) were studied using various in silico tools, such as pkCSM software to predict ADMET properties and PASS Online software to predict anticancer activity. However, the molecular docking study provided the binding energies and inhibition constant and confirmed the interaction between PKM2 and the ligands. The dynamic behaviour, conformational changes, and stability between PKM2 and the top three hit compounds (Verbascoside (Ver), Rutin (Rut), and Luteolin_7_O_glucoside (Lut)) are studied by MD simulations.


Asunto(s)
Antineoplásicos , Neoplasias , Olea , Antineoplásicos/farmacología , Glucósidos/farmacología , Humanos , Luteolina , Micronutrientes , Simulación del Acoplamiento Molecular , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Olea/química , Extractos Vegetales , Piruvato Quinasa/metabolismo , Ácido Pirúvico , Rutina
13.
ACS Synth Biol ; 11(10): 3216-3227, 2022 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-36130255

RESUMEN

Engineered microbes can be used for producing value-added chemicals from renewable feedstocks, relieving the dependency on nonrenewable resources such as petroleum. These microbes often are composed of synthetic metabolic pathways; however, one major problem in establishing a synthetic pathway is the challenge of precisely controlling competing metabolic routes, some of which could be crucial for fitness and survival. While traditional gene deletion and/or coarse overexpression approaches do not provide precise regulation, cis-repressors (CRs) are RNA-based regulatory elements that can control the production levels of a particular protein in a tunable manner. Here, we describe a protocol for a generally applicable fluorescence-activated cell sorting technique used to isolate eight subpopulations of CRs from a semidegenerate library in Escherichia coli, followed by deep sequencing that permitted the identification of 15 individual CRs with a broad range of protein production profiles. Using these new CRs, we demonstrated a change in production levels of a fluorescent reporter by over two orders of magnitude and further showed that these CRs are easily ported from E. coli to Pseudomonas putida. We next used four CRs to tune the production of the enzyme PpsA, involved in pyruvate to phosphoenolpyruvate (PEP) conversion, to alter the pool of PEP that feeds into the shikimate pathway. In an engineered P. putida strain, where carbon flux in the shikimate pathway is diverted to the synthesis of the commodity chemical cis,cis-muconate, we found that tuning PpsA translation levels increased the overall titer of muconate. Therefore, CRs provide an approach to precisely tune protein levels in metabolic pathways and will be an important tool for other metabolic engineering efforts.


Asunto(s)
Petróleo , Pseudomonas putida , Escherichia coli/genética , Escherichia coli/metabolismo , Fosfoenolpiruvato/metabolismo , Pseudomonas putida/genética , Pseudomonas putida/metabolismo , Ingeniería Metabólica , Ácido Pirúvico/metabolismo , Genómica , ARN/metabolismo , Petróleo/metabolismo
15.
J Biol Chem ; 298(9): 102286, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35868562

RESUMEN

In the mammalian retina, a metabolic ecosystem exists in which photoreceptors acquire glucose from the choriocapillaris with the help of the retinal pigment epithelium (RPE). While the photoreceptor cells are primarily glycolytic, exhibiting Warburg-like metabolism, the RPE is reliant on mitochondrial respiration. However, the ways in which mitochondrial metabolism affect RPE cellular functions are not clear. We first used the human RPE cell line, ARPE-19, to examine mitochondrial metabolism in the context of cellular differentiation. We show that nicotinamide induced rapid differentiation of ARPE-19 cells, which was reversed by removal of supplemental nicotinamide. During the nicotinamide-induced differentiation, we observed using quantitative PCR, Western blotting, electron microscopy, and metabolic respiration and tracing assays that (1) mitochondrial gene and protein expression increased, (2) mitochondria became larger with more tightly folded cristae, and (3) mitochondrial metabolism was enhanced. In addition, we show that primary cultures of human fetal RPE cells responded similarly in the presence of nicotinamide. Furthermore, disruption of mitochondrial oxidation of pyruvate attenuated the nicotinamide-induced differentiation of the RPE cells. Together, our results demonstrate a remarkable effect of nicotinamide on RPE metabolism. We also identify mitochondrial respiration as a key contributor to the differentiated state of the RPE and thus to many of the RPE functions that are essential for retinal health and photoreception.


Asunto(s)
Diferenciación Celular , Mitocondrias , Niacinamida , Epitelio Pigmentado de la Retina , Animales , Diferenciación Celular/efectos de los fármacos , Línea Celular , Glucosa/metabolismo , Humanos , Mitocondrias/genética , Mitocondrias/metabolismo , Niacinamida/farmacología , Ácido Pirúvico/metabolismo , Epitelio Pigmentado de la Retina/citología , Epitelio Pigmentado de la Retina/efectos de los fármacos , Epitelio Pigmentado de la Retina/metabolismo
16.
Plant Physiol ; 190(2): 1117-1133, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-35876823

RESUMEN

In C4 plants, the pyruvate (Pyr), phosphate dikinase regulatory protein (PDRP) regulates the activity of the C4 pathway enzyme Pyr, phosphate dikinase (PPDK) in a light-/dark-dependent manner. The importance of this regulatory action to C4 pathway function and overall C4 photosynthesis is unknown. To resolve this question, we assessed in vivo PPDK phospho-regulation and whole leaf photophysiology in a CRISPR-Cas9 PDRP knockout (KO) mutant of the NADP-ME C4 grass green millet (Setaria viridis). PDRP enzyme activity was undetectable in leaf extracts from PDRP KO lines. Likewise, PPDK phosphorylated at the PDRP-regulatory Thr residue was immunologically undetectable in leaf extracts. PPDK enzyme activity in rapid leaf extracts was constitutively high in the PDRP KO lines, irrespective of light or dark pretreatment of leaves. Gas exchange analysis of net CO2 assimilation revealed PDRP KO leaves had markedly slower light induction kinetics when leaves transition from dark to high-light or low-light to high-light. In the initial 30 min of the light induction phase, KO leaves had an ∼15% lower net CO2 assimilation rate versus the wild-type (WT). Despite the impaired slower induction kinetics, we found growth and vigor of the KO lines to be visibly indistinguishable from the WT when grown in normal air and under standard growth chamber conditions. However, the PDRP KO plants grown under a fluctuating light regime exhibited a gradual multi-day decline in Fv/Fm, indicative of progressive photosystem II damage due to the absence of PDRP. Collectively, our results demonstrate that one of PDRP's functions in C4 photosynthesis is to ensure optimal photosynthetic light induction kinetics during dynamic changes in incident light.


Asunto(s)
Piruvato Ortofosfato Diquinasa , Setaria (Planta) , Dióxido de Carbono/metabolismo , NADP/metabolismo , Fosfatos/metabolismo , Fotosíntesis , Complejo de Proteína del Fotosistema II/metabolismo , Extractos Vegetales/metabolismo , Plantas/metabolismo , Piruvato Ortofosfato Diquinasa/química , Ácido Pirúvico/metabolismo , Setaria (Planta)/genética , Setaria (Planta)/metabolismo , Factores de Transcripción/metabolismo , Zea mays/metabolismo
17.
Fish Physiol Biochem ; 48(3): 555-570, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35461391

RESUMEN

Excessive lipid deposition in farmed fish is a challenge in the aquaculture industry. To study the effect of dietary calcium pyruvate (CaP) on lipid accumulation in fish, we used a high fat diet (HFD) to establish a lipid accumulation model in juvenile golden pompano (Trachinotus ovatus) and supplemented with 0%, 0.25%, 0.50%, 0.75% and 1.0% CaP (diets D0-D4, respectively). After 8-week feeding in floating cages, dietary CaP significantly improved growth performance, which peaked in fish fed diet D3. Supplementation of CaP significantly decreased whole body lipid content in fish fed D2-D4 and hepatosomatic index and liver lipid content in fish fed D3 and D4. Serum and hepatic antioxidant indices, including glutathione, catalase and superoxide dismutase, showed generally increasing trends in fish fed diets with CaP. In addition, increasing dietary CaP increasingly reduced hepatic activities of hexokinase, phosphofructokinase and pyruvate kinase involved in glycolysis, and increased glycogen contents of the liver and muscle. Dietary CaP up-regulated the liver mRNA expression of pparα, cpt1, hsl and fabp1, but down-regulated expression of srebp-1, fas and acc. In conclusion, 0.75% CaP improved growth performance and reduced excessive lipid deposition by affecting fatty acid synthesis and lipolysis in juvenile T. ovatus fed HFD.


Asunto(s)
Dieta Alta en Grasa , Perciformes , Alimentación Animal/análisis , Animales , Calcio de la Dieta/metabolismo , Calcio de la Dieta/farmacología , Dieta , Suplementos Dietéticos , Peces , Metabolismo de los Lípidos , Lípidos/farmacología , Hígado/metabolismo , Perciformes/metabolismo , Ácido Pirúvico/metabolismo , Ácido Pirúvico/farmacología
18.
PLoS One ; 17(1): e0262705, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35045129

RESUMEN

Onion (Allium cepa L) is a major reservoir of important nutraceutical ingredients. Herein, nutraceutical profiling of elite germplasm was assessed and hybrids with improved nutraceutical quality were selected. The nutraceutical components were screened through Fourier Transform Infrared Spectroscopy (FTIR) analysis (scan range 4000-400cm-1) followed by spectrophotometric/colorimetric quantification in oven dried bulb samples. Line × Tester (L×T) analysis was used to identify potential hybrids with better nutraceutical quality. Based on common functional groups obtained from FTIR analysis, as well as bulb color, the onion genotypes were categorized into six groups viz., white, yellowish brown, light brown, dark brown, brown and purplish brown. Results indicated that the purplish brown, yellowish brown and dark brown genotypes had maximum concentration of pyruvic acid, total flavonoids and total phenolic content, while vitamin C content showed weak association with color pigmentation. The onion variety 'Onion Swat' contained the highest level of pyruvic acid (17.18 µM) and 'MKS8823GO' had the highest vitamin C content (13.83mg/100mL). The L×T analysis revealed that out of 35 crosses, 'MKS-77127 × Onion Swat' and 'MKS-77127 × MKS777' were the best hybrids with improved nutraceutical quality. Further, observations for specific combining ability, general combining ability, genetic versus environmental variance, heritability and heterosis indicated that the studied parameters were genetically inherited and could be improved significantly by adopting an appropriate breeding strategy.


Asunto(s)
Suplementos Dietéticos/análisis , Cebollas/metabolismo , Semillas/metabolismo , Antioxidantes/análisis , Flavonoides/análisis , Genotipo , Cebollas/química , Cebollas/genética , Fenoles/análisis , Fenotipo , Pigmentación , Fitomejoramiento/métodos , Raíces de Plantas/química , Ácido Pirúvico/análisis , Espectrofotometría , Espectroscopía Infrarroja por Transformada de Fourier/métodos
19.
BMC Vet Res ; 18(1): 35, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-35033088

RESUMEN

BACKGROUND: The fasting and stress associated with road transportation contributes to a lack of energy and a decline in the immune system of beef cattle. Therefore, it is essential for beef cattle to enhance energy reserves before transportation. Creatine pyruvate (CrPyr) is a new multifunctional nutrient that can provide both pyruvate and creatine, which are two intermediate products of energy metabolism. To investigate the effects of transport and rumen-protected (RP)-CrPyr on the blood biochemical parameters and rumen fluid characteristics of beef cattle, twenty male Simmental crossbred cattle (659 ± 16 kg) aged 18 months were randomly allocated to four groups (n = 5) using a 2 × 2 factorial arrangement with two RP-CrPyr supplemental levels (0 or 140 g/d) and two transport treatments (5 min or 12 h): T_CrPyr140, T_CrPyr0, NT_CrPyr140, and NT_CrPyr0. After feeding for 30 days, three cattle per treatment were slaughtered. RESULTS: Compared with nontransport, transport decreased the total antioxidant capacity, catalase activity, contents of IgA, interferon γ, interleukin-1ß (IL-1ß), and IL-6 in serum, and the amounts of total volatile fatty acids (TVFA), acetate, and butyrate in rumen (P < 0.05); increased the serum lipopolysaccharide (LPS) level, contents of rumen LPS and ammonia nitrogen (P < 0.05). RP-CrPyr supplementation decreased the levels of cortisol and LPS in serum and the butyrate concentration in the rumen of beef cattle compared with those in the unsupplemented groups (P < 0.05). RP-CrPyr and transport interaction had a significant effect on the contents of serum tumour necrosis factor-α, IL-6, LPS, ruminal pH, acetate content, and acetate/propionate (P < 0.05). In terms of ruminal bacterial composition, group T_CrPyr0 increased the Prevotella genus abundance compared with group NT_CrPyr0 (P < 0.05), while group T_CrPyr140 increased Firmicutes phylum abundance and decreased Bacteroidetes phylum and genus Prevotella abundance compared with group T_CrPyr0 (P < 0.05). Moreover, Bacteroidetes was positively correlated with serum LPS. CONCLUSIONS: These results indicated that dietary supplementation with RP-CrPyr might be beneficial to alleviate transport stress by decreasing serum cortisol and LPS levels and promoting the restoration of the rumen natural flora.


Asunto(s)
Creatina , Suplementos Dietéticos , Ácido Pirúvico , Rumen , Acetatos , Alimentación Animal/análisis , Animales , Butiratos , Bovinos , Creatina/administración & dosificación , Dieta/veterinaria , Fermentación , Hidrocortisona/metabolismo , Interleucina-6/metabolismo , Lipopolisacáridos/metabolismo , Masculino , Prevotella , Ácido Pirúvico/administración & dosificación , Rumen/metabolismo
20.
NMR Biomed ; 35(6): e4678, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34961990

RESUMEN

Personalized medicine or individualized therapy promises a paradigm shift in healthcare. This is particularly true in complex and multifactorial diseases such as diabetes and the multitude of related pathophysiological complications. Diabetic cardiomyopathy represents an emerging condition that could be effectively treated if better diagnostic and, in particular, better therapeutic monitoring tools were available. In this study, we investigate the ability to differentiate low and high doses of metabolically targeted therapy in an obese type 2 diabetic rat model. Low-dose dichloroacetate (DCA) treatment was associated with increased lactate production, while no or little change was seen in bicarbonate production. High-dose DCA treatment was associated with a significant metabolic switch towards increased bicarbonate production. These findings support further studies using hyperpolarized [1-13 C]-pyruvate magnetic resonance imaging to differentiate treatment effects and thus allow for personalized titration of therapeutics.


Asunto(s)
Diabetes Mellitus Tipo 2 , Ácido Pirúvico , Acetatos , Animales , Bicarbonatos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico por imagen , Ácido Dicloroacético/farmacología , Ácido Dicloroacético/uso terapéutico , Corazón/diagnóstico por imagen , Corazón/fisiología , Imagen por Resonancia Magnética/métodos , Ácido Pirúvico/metabolismo , Ratas
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