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1.
ACS Appl Bio Mater ; 7(5): 3179-3189, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38581305

RESUMO

Ruxolitinib (RXL) is a Janus kinase inhibitor used for treating intermediate- or high-risk myelofibrosis. This study presents an electrode modified with electrochemically polymerized taurine on a carbon paste electrode via cyclic voltammetry (CV). The surface characterization of the poly(taurine)-CP electrode was evaluated by using electrochemical (electrochemical impedance spectroscopy─EIS, CV), morphological (scanning electron microscope─SEM), and spectroscopic (Fourier-transform infrared spectroscopy─FT-IR) techniques. Under optimized conditions, RXL exhibited good linearity within the 0.01-1.0 µM concentration range, with a limit of detection (LOD) of 0.005 µM. The proposed electrochemical sensor demonstrated excellent selectivity, accuracy, precision, and repeatability. Furthermore, it effectively detected RXL in human urine and pharmaceutical samples.


Assuntos
Carbono , Técnicas Eletroquímicas , Eletrodos , Teste de Materiais , Nitrilas , Pirazóis , Pirimidinas , Taurina , Nitrilas/química , Nitrilas/farmacologia , Pirimidinas/química , Pirimidinas/farmacologia , Carbono/química , Humanos , Pirazóis/química , Pirazóis/farmacologia , Taurina/química , Taurina/análogos & derivados , Taurina/farmacologia , Tamanho da Partícula , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Inibidores de Janus Quinases/química , Inibidores de Janus Quinases/farmacologia , Polimerização , Estrutura Molecular
2.
Nutr J ; 23(1): 28, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38429722

RESUMO

BACKGROUND: The relationship between circulating bile acids (BAs) and kidney function among patients with type 2 diabetes is unclear. We aimed to investigate the associations of circulating concentrations of BAs, particularly individual BA subtypes, with chronic kidney disease (CKD) in patients of newly diagnosed type 2 diabetes. METHODS: In this cross-sectional study, we included 1234 newly diagnosed type 2 diabetes who participated in an ongoing prospective study, the Dongfeng-Tongji cohort. Circulating primary and secondary unconjugated BAs and their taurine- or glycine-conjugates were measured using ultraperformance liquid chromatography-tandem mass spectrometry. CKD was defined as eGFR < 60 ml/min per 1.73 m2. Logistic regression model was used to compute odds ratio (OR) and 95% confidence interval (CI). RESULTS: After adjusting for multiple testing, higher levels of total primary BAs (OR per standard deviation [SD] increment: 0.78; 95% CI: 0.65-0.92), cholate (OR per SD: 0.78; 95% CI: 0.66-0.92), chenodeoxycholate (OR per SD: 0.81; 95% CI: 0.69-0.96), glycocholate (OR per SD: 0.81; 95% CI: 0.68-0.96), and glycochenodeoxycholate (OR per SD: 0.82; 95% CI: 0.69-0.97) were associated with a lower likelihood of having CKD in patients with newly diagnosed type 2 diabetes. No significant relationships between secondary BAs and odds of CKD were observed. CONCLUSIONS: Our findings showed that higher concentrations of circulating unconjugated primary BAs and their glycine-conjugates, but not taurine-conjugates or secondary BAs, were associated with lower odds of having CKD in patients with type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Humanos , Ácidos e Sais Biliares , Estudos Transversais , Estudos Prospectivos , Diabetes Mellitus Tipo 2/epidemiologia , Taurina/química , Glicina , Insuficiência Renal Crônica/epidemiologia
3.
Chemistry ; 28(9): e202104167, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-34967481

RESUMO

Taurine/α-ketoglutarate dioxygenase is an important enzyme that takes part in the cysteine catabolism process in the human body and selectively hydroxylates taurine at the C1 -position. Recent computational studies showed that in the gas-phase the C2 -H bond of taurine is substantially weaker than the C1 -H bond, yet no evidence exists of 2-hydroxytaurine products. To this end, a detailed computational study on the selectivity patterns in TauD was performed. The calculations show that the second-coordination sphere and the protonation states of residues play a major role in guiding the enzyme to the right selectivity. Specifically, a single proton on an active site histidine residue can change the regioselectivity of the reaction through its electrostatic perturbations in the active site and effectively changes the C1 -H and C2 -H bond strengths of taurine. This is further emphasized by many polar and hydrogen bonding interactions of the protein cage in TauD with the substrate and the oxidant that weaken the pro-R C1 -H bond and triggers a chemoselective reaction process. The large cluster models reproduce the experimental free energy of activation excellently.


Assuntos
Dioxigenases , Ácidos Cetoglutáricos , Dioxigenases/metabolismo , Humanos , Ferro/química , Ácidos Cetoglutáricos/química , Eletricidade Estática , Taurina/química , Taurina/metabolismo
4.
Chem Biol Interact ; 351: 109715, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34695389

RESUMO

Owing to the poor outcomes and adverse side effects of existing ulcerative colitis drugs, the study aimed to develop an alternative nano-based treatment approach. The study was designed to characterize the in vitro and in vivo properties of taurine, taurine-loaded chitosan pectin nanoparticles (Tau-CS-PT-NPs) and chitosan pectin nanoparticles (CS-PT-NPs) in the therapy of acetic acid (AA)-induced colitis in rats. CS-PT-NPs and Tau-CS-PT-NPs were prepared by ionic gelation method then in vitro characterized, including transmission electron microscopy (TEM), polydispersity index (PDI), zeta potential, Fourier transform infrared (FTIR) spectroscopy, encapsulation efficiency (EE), and drug release profile. Following colitis induction, rats were orally administrated with free taurine, Tau-CS-PT-NPs, and CS-PT-NPs once per day for six days. The sizes of Tau-CS-PT-NPs and CS-PT-NPs were 74.17 ± 2.88 nm and 42.22 ± 2.41 nm, respectively. EE was about 69.09 ± 1.58%; furthermore, 60% of taurine was released in 4 h in simulated colon content. AA-induced colitis in untreated rats led to necrosis of colon tissues and a significant increase in interleukin-1beta (IL-1ß), Tumor Necrosis Factor-alpha (TNF-α), myeloperoxidase (MPO), and malondialdehyde (MDA) levels associated with a remarkable reduction in glutathione (GSH) level in colon tissue in comparison to control group. Treatment with taurine, Tau-CS-PT-NPs, and CS-PT-NPs partly reversed these effects. The present study demonstrated that the administration of free taurine, CS-PT-NPs, and Tau-CS-PT-NPs exerted beneficial effects in acetic acid-induced colitis by their anti-inflammatory and antioxidant activities. The best therapeutic effect was observed in animals treated with taurine-loaded chitosan pectin nanoparticles.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite/tratamento farmacológico , Portadores de Fármacos/química , Nanopartículas/química , Taurina/uso terapêutico , Ácido Acético , Animais , Anti-Inflamatórios/química , Quitosana/química , Colite/induzido quimicamente , Colite/patologia , Liberação Controlada de Fármacos , Masculino , Estresse Oxidativo/efeitos dos fármacos , Pectinas/química , Ratos Wistar , Taurina/química
5.
Molecules ; 26(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34443494

RESUMO

Taurine is a naturally occurring sulfur-containing amino acid that is found abundantly in excitatory tissues, such as the heart, brain, retina and skeletal muscles. Taurine was first isolated in the 1800s, but not much was known about this molecule until the 1990s. In 1985, taurine was first approved as the treatment among heart failure patients in Japan. Accumulating studies have shown that taurine supplementation also protects against pathologies associated with mitochondrial defects, such as aging, mitochondrial diseases, metabolic syndrome, cancer, cardiovascular diseases and neurological disorders. In this review, we will provide a general overview on the mitochondria biology and the consequence of mitochondrial defects in pathologies. Then, we will discuss the antioxidant action of taurine, particularly in relation to the maintenance of mitochondria function. We will also describe several reported studies on the current use of taurine supplementation in several mitochondria-associated pathologies in humans.


Assuntos
Antioxidantes/metabolismo , Mitocôndrias/metabolismo , Taurina/metabolismo , Animais , Apoptose , Ensaios Clínicos como Assunto , Humanos , Doenças Mitocondriais/metabolismo , Taurina/química
6.
ACS Chem Biol ; 16(5): 864-871, 2021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-33843182

RESUMO

Although numerous in vitro studies have shown that osmolytes are capable of stabilizing proteins, their effect on protein folding in vivo has been less understood. In this work, we investigated the effect of osmolytes, including glycerol, sorbitol, betaine, and taurine, on the folding of a protein GB3 variant in E. coli cells using NMR spectroscopy. 400 mM osmolytes were added to E. coli cells; only glycerol stabilizes the folded protein, whereas betaine and taurine considerably destabilize the protein through modulating folding and unfolding rates. Further investigation indicates that betaine and taurine can enhance the quinary interaction between the protein and cellular environment and manifestly weaken the electrostatic attraction in protein salt bridges. The combination of the two factors causes destabilization of the protein in E. coli cells. These factors counteract the preferential exclusion mechanism that is adopted by osmolytes to stabilize proteins.


Assuntos
Proteínas de Bactérias/química , Dobramento de Proteína/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Proteínas/química , Betaína/química , Escherichia coli/química , Glicerol/química , Interações Hidrofóbicas e Hidrofílicas , Modelos Moleculares , Sorbitol/química , Eletricidade Estática , Taurina/química , Termodinâmica
7.
Cells ; 10(2)2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525569

RESUMO

It is a widely known that heat stress induces a reduction in milk production in cows and impairs their overall health. Studies have shown that taurine protects tissues and organs under heat stress. However, there have yet to be studies showing the functions of taurine in mammary alveolar cells-large T antigen (MAC-T) (a bovine mammary epithelial cell line) cells under heat shock. Therefore, different concentrations of taurine (10 mM, 50 mM, and 100 mM) were tested to determine the effects on heat-induced MAC-T cells. The results showed that taurine protected the cells against heat-induced damage as shown by morphological observations in conjunction with suppressed the translocation and expression of heat shock factor 1 (HSF1). Moreover, taurine not only reversed the decline in antioxidase (superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX)) activities but also attenuated the accumulation of malondialdehyde (MDA). Meanwhile, mitochondrial damage (morphology and complex I activity) resulting from heat exposure was mitigated. Taurine also alleviated the rates of cell apoptosis and markedly depressed the mRNA expressions of BCL2 associated X, apoptosis regulator (BAX) and caspase3. Furthermore, compared with the heat stress (HS) group, the protein levels of caspase3 and cleaved caspase3 were decreased in all taurine groups. In summary, taurine improves the antioxidant and anti-apoptosis ability of MAC-T cells thereby alleviates damage of cells due to heat insults.


Assuntos
Citoproteção , Células Epiteliais/efeitos dos fármacos , Resposta ao Choque Térmico , Glândulas Mamárias Animais/citologia , Substâncias Protetoras/farmacologia , Taurina/farmacologia , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Bovinos , Linhagem Celular , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Complexo I de Transporte de Elétrons/metabolismo , Feminino , Resposta ao Choque Térmico/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Taurina/química
8.
J Struct Biol ; 213(1): 107674, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33253877

RESUMO

Pyridoxal 5́-phosphate (PLP) is an important cofactor for amino acid decarboxylases with many biological functions, including the synthesis of signalling molecules, such as serotonin, dopamine, histamine, γ-aminobutyric acid, and taurine. Taurine is an abundant amino acid with multiple physiological functions, including osmoregulation, pH regulation, antioxidative protection, and neuromodulation. In mammalian tissues, taurine is mainly produced by decarboxylation of cysteine sulphinic acid to hypotaurine, catalysed by the PLP-dependent cysteine sulphinic acid decarboxylase (CSAD), followed by oxidation of the product to taurine. We determined the crystal structure of mouse CSAD and compared it to other PLP-dependent decarboxylases in order to identify determinants of substrate specificity and catalytic activity. Recognition of the substrate involves distinct side chains forming the substrate-binding cavity. In addition, the backbone conformation of a buried active-site loop appears to be a critical determinant for substrate side chain binding in PLP-dependent decarboxylases. Phe94 was predicted to affect substrate specificity, and its mutation to serine altered both the catalytic properties of CSAD and its stability. Using small-angle X-ray scattering, we further showed that CSAD presents open/close motions in solution. The structure of apo-CSAD indicates that the active site gets more ordered upon internal aldimine formation. Taken together, the results highlight details of substrate recognition in PLP-dependent decarboxylases and provide starting points for structure-based inhibitor design with the aim of affecting the biosynthesis of taurine and other abundant amino acid metabolites.


Assuntos
Carboxiliases/química , Carboxiliases/metabolismo , Cisteína/análogos & derivados , Taurina/química , Sequência de Aminoácidos , Animais , Domínio Catalítico/fisiologia , Cisteína/química , Cisteína/metabolismo , Camundongos , Ligação Proteica/fisiologia , Fosfato de Piridoxal/química , Fosfato de Piridoxal/metabolismo , Especificidade por Substrato , Taurina/análogos & derivados , Taurina/metabolismo
9.
Oxid Med Cell Longev ; 2020: 8294158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33062147

RESUMO

Sulfur contributes significantly to nature chemical diversity and thanks to its particular features allows fundamental biological reactions that no other element allows. Sulfur natural compounds are utilized by all living beings and depending on the function are distributed in the different kingdoms. It is no coincidence that marine organisms are one of the most important sources of sulfur natural products since most of the inorganic sulfur is metabolized in ocean environments where this element is abundant. Terrestrial organisms such as plants and microorganisms are also able to incorporate sulfur in organic molecules to produce primary metabolites (e.g., methionine, cysteine) and more complex unique chemical structures with diverse biological roles. Animals are not able to fix inorganic sulfur into biomolecules and are completely dependent on preformed organic sulfurous compounds to satisfy their sulfur needs. However, some higher species such as humans are able to build new sulfur-containing chemical entities starting especially from plants' organosulfur precursors. Sulfur metabolism in humans is very complicated and plays a central role in redox biochemistry. The chemical properties, the large number of oxidation states, and the versatile reactivity of the oxygen family chalcogens make sulfur ideal for redox biological reactions and electron transfer processes. This review will explore sulfur metabolism related to redox biochemistry and will describe the various classes of sulfur-containing compounds spread all over the natural kingdoms. We will describe the chemistry and the biochemistry of well-known metabolites and also of the unknown and poorly studied sulfur natural products which are still in search for a biological role.


Assuntos
Compostos de Enxofre/metabolismo , Animais , Cisteína/metabolismo , Glutationa/metabolismo , Glicosídeo Hidrolases/metabolismo , Humanos , Metionina/metabolismo , Oxirredução , Plantas/química , Plantas/metabolismo , Compostos de Enxofre/química , Taurina/biossíntese , Taurina/química
10.
Amino Acids ; 52(1): 35-53, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31781908

RESUMO

Hexavalent chromium [(Cr(VI)] is widely used in several industries, but human exposure results in multiple organ toxicity. Enhanced generation of free radicals and reactive species is thought to play a key role in Cr(VI)-induced toxicity. We have examined the effect of taurine, a simple sulphur-containing amino acid and an antioxidant, on potassium dichromate [K2Cr2O7, a Cr(VI) compound]-induced cytotoxicity and genotoxicity in human blood cells. Erythrocytes were treated with K2Cr2O7, either alone or after incubation with different concentrations of taurine. Treatment of erythrocytes with K2Cr2O7 alone led to marked increase in generation of reactive oxygen and nitrogen species, lipid and protein oxidation. This was accompanied by decrease in total sulfhydryl and glutathione content and lowered antioxidant power of the cells. This suggests that Cr(VI) induces oxidative stress in the cells. Incubation of erythrocytes with taurine prior to addition of K2Cr2O7, resulted in a concentration-dependent decrease in the generation of reactive oxygen and nitrogen species, mitigation of oxidative stress and amelioration of antioxidant power of these cells. It also restored the activities of several metabolic, antioxidant and membrane-bound enzymes. Cr(VI)-induced damage to erythrocyte membrane and lymphocyte DNA was also significantly attenuated by prior administration of taurine. These results suggest that taurine can function as a chemoprotectant against Cr(VI)-induced oxidative injury and can be potentially used to mitigate the toxic effects of this transition metal ion.


Assuntos
Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Taurina/farmacologia , Antioxidantes/química , Cromo/toxicidade , Eritrócitos/efeitos dos fármacos , Radicais Livres/química , Radicais Livres/farmacologia , Glutationa/química , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Taurina/química
11.
Mikrochim Acta ; 186(12): 746, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31691865

RESUMO

Well-dispersed and graft-crosslinked gold nanoparticles (AuNPs) were synthesized by the reduction of tetrachloroaurate with hydrazine at room temperature. The AuNPs possess a high density of surface defects which is due to grafting of n-octanoic acid to polyvinylpyrrolidone. The physical and chemical properties of the resulting AuNPs were characterized by UV-vis, XRD, TEM/HRTEM, SAED, and XPS, respectively. The modified AuNPs were placed on a glassy carbon electrode (GCE) in an electropolymerized taurine layer to obtain a sensitive, selective, stable and rapid electrochemical dopamine sensor. The peak current, typically measured at 0.17 V (vs. SCE), increases linearly in the 1.0 to 120 µM dopamine concentration range, and the limit of detection (at S/N = 3) is 0.16 µM with a sensitivity of 2.94 µA·µM-1·cm-2. The sensor was successfully applied to the determination of dopamine in injections and spiked serum samples. The recoveries from spiked serum samples range from 97.5 to 102.4%, with RSDs ranging between 2.8 and 3.4%. Graphical abstract Schematic representation of a glassy carbon electrode modified with in-situ graft-crosslinked gold nanoparticles combined with an electropolymerized polytaurine membrane. The sensor exhibits excellent features towards dopamine determination.


Assuntos
Dopamina/sangue , Nanopartículas Metálicas/química , Polímeros/química , Caprilatos/química , Carbono/química , Dopamina/química , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Humanos , Limite de Detecção , Membranas Artificiais , Oxirredução , Polimerização , Polímeros/síntese química , Povidona/química , Reprodutibilidade dos Testes , Taurina/química
12.
Biochemistry ; 58(41): 4218-4223, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31503454

RESUMO

Iron(II)- and 2-(oxo)-glutarate-dependent (Fe/2OG) oxygenases catalyze a diverse array of oxidation reactions via a common iron(IV)-oxo (ferryl) intermediate. Although the intermediate has been characterized spectroscopically, its short lifetime has precluded crystallograhic characterization. In solution, the ferryl was first observed directly in the archetypal Fe/2OG hydroxylase, taurine:2OG dioxygenase (TauD). Here, we substitute the iron cofactor of TauD with the stable vanadium(IV)-oxo (vanadyl) ion to obtain crystal structures mimicking the key ferryl complex. Intriguingly, whereas the structure of the TauD·(VIV-oxo)·succinate·taurine complex exhibits the expected orientation of the V≡O bond-trans to the His255 ligand and toward the C-H bond to be cleaved, in what has been termed the in-line configuration-the TauD·(VIV-oxo) binary complex is best modeled with its oxo ligand trans to Asp101. This off-line-like configuration is similar to one recently posited as a means to avoid hydroxylation in Fe/2OG enzymes that direct other outcomes, though neither has been visualized in an Fe/2OG structure to date. Whereas an off-line (trans to the proximal His) or off-line-like (trans to the carboxylate ligand) ferryl is unlikely to be important in the hydroxylation reaction of TauD, the observation that the ferryl may deviate from an in-line orientation in the absence of the primary substrate may explain the enzyme's mysterious self-hydroxylation behavior, should the oxo ligand lie trans to His99. This finding reinforces the potential for analogous functional off-line oxo configurations in halogenases, desaturases, and/or cyclases.


Assuntos
Ferro/química , Oxigenases de Função Mista/química , Mimetismo Molecular , Vanadatos/química , Domínio Catalítico , Cristalização , Cristalografia por Raios X , Escherichia coli/química , Ligação de Hidrogênio , Hidroxilação , Oxigenases de Função Mista/isolamento & purificação , Estrutura Secundária de Proteína , Ácido Succínico/química , Taurina/química , Espectroscopia por Absorção de Raios X
13.
Molecules ; 24(6)2019 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-30909659

RESUMO

Alzheimer's Disease affects approximately 33 million people worldwide and is characterized by progressive loss of memory at the cognitive level. The formation of toxic amyloid oligomers, extracellular amyloid plaques and amyloid angiopathy in brain by amyloid beta peptides are considered a part of the identified mechanism involved in disease pathogenesis. The optimal treatment approach leads toward finding a chemical compound able to form a noncovalent complex with the amyloid peptide thus blocking the process of amyloid aggregation. This direction gained an increasing interest lately, many studies demonstrating that mass spectrometry is a valuable method useful for the identification and characterization of such molecules able to interact with amyloid peptides. In the present review we aim to identify in the scientific literature low molecular weight chemical compounds for which there is mass spectrometric evidence of noncovalent complex formation with amyloid peptides and also there are toxicity reduction results which verify the effects of these compounds on amyloid beta toxicity towards cell cultures and transgenic mouse models developing Alzheimer's Disease.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Espectrometria de Massas/métodos , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/toxicidade , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Dissacarídeos/química , Dissacarídeos/farmacologia , Modelos Animais de Doenças , Humanos , Camundongos Transgênicos , Peso Molecular , Fármacos Neuroprotetores/uso terapêutico , Peptídeos/química , Peptídeos/farmacologia , Taurina/análogos & derivados , Taurina/química , Taurina/farmacologia
14.
Biotechnol J ; 14(4): e1800352, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30485675

RESUMO

There is continual demand to maximize CHO cell culture productivity of a biotherapeutic while maintaining product quality. In this study, a comprehensive multi-omics analysis is performed to investigate the cellular response to the level of dosing of the amino acid cysteine (Cys) in the production of a monoclonal antibody (mAb). When Cys feed levels are insufficient, there is a significant decrease in protein titer. Multi-omics (metabolomics and proteomics, with support from RNAseq) is performed over the time course of the CHO bioprocess producing an IgG1 mAb in 5 L bioreactors. Pathway analysis reveals that insufficient levels of Cys in the feed lead to Cys depletion in the cell. This depletion negatively impacts antioxidant molecules, such as glutathione (GSH) and taurine, leading to oxidative stress with multiple deleterious cellular effects. In this paper, the resultant ER stress and subsequent apoptosis that affects cell viability and viable cell density has been considered. Key metabolic enzymes and metabolites are identified that can be potentially monitored as the process progresses and/or increased in the cell either by nutrient feeding or genetic engineering. This work reinforces the centrality of redox balance to cellular health and success of the bioprocess as well as the power of multi-omics to provide an in-depth understanding of the CHO cell biology during biopharmaceutical production.


Assuntos
Anticorpos Monoclonais/biossíntese , Técnicas de Cultura de Células , Meios de Cultura/farmacologia , Cisteína/farmacologia , Animais , Anticorpos Monoclonais/efeitos dos fármacos , Reatores Biológicos , Células CHO , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Cisteína/química , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Glutationa/química , Imunoglobulina G/biossíntese , Imunoglobulina G/química , Estresse Oxidativo/efeitos dos fármacos , Proteômica , Taurina/química
15.
Molecules ; 23(12)2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30513982

RESUMO

Osmolytes are small organic compounds that can affect the stability of proteins in living cells. The mechanism of osmolytes' protective effects on protein structure and dynamics has not been fully explained, but in general, two possibilities have been suggested and examined: a direct interaction of osmolytes with proteins (water replacement hypothesis), and an indirect interaction (vitrification hypothesis). Here, to investigate these two possible mechanisms, we studied myoglobin-osmolyte systems using FTIR, UV-vis, CD, and femtosecond IR pump-probe spectroscopy. Interestingly, noticeable changes are observed in both the lifetime of the CO stretch of CO-bound myoglobin and the spectra of UV-vis, CD, and FTIR upon addition of the osmolytes. In addition, the temperature-dependent CD studies reveal that the protein's thermal stability depends on molecular structure, hydrogen-bonding ability, and size of osmolytes. We anticipate that the present experimental results provide important clues about the complicated and intricate mechanism of osmolyte effects on protein structure and dynamics in a crowded cellular environment.


Assuntos
Mioglobina/química , Osmose , Betaína/química , Dicroísmo Circular , Inositol/química , Mioglobina/metabolismo , Estabilidade Proteica , Sorbitol/química , Espectrofotometria Infravermelho/métodos , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Taurina/química , Temperatura , Trealose/química
16.
Mol Med Rep ; 18(5): 4516-4522, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30221665

RESUMO

The protective effect of taurine against inflammation, apoptosis and oxidative stress in traumatic brain injury was investigated in the present study. Taurine is a non­proteogenic and essential amino acid in animals. It plays a critical nutritional role in brain cell growth, differentiation, and development. Taurine is involved in regeneration and neuroprotection in the injured nervous system, and is an effective antioxidant against lead­, cadmium­, and exercise­induced oxidative stress. Astrocytes and neuron cells were co­cultured and cells were treated with different concentrations of taurine (100, 200 and 300 mg/l) for 72 h, and the levels of reactive oxygen species, malondialdehyde, reduced glutathione, glutathione peroxidase, superoxide dismutase, catalase, acetylcholinesterase, tumor necrosis factor­α, interleukin­6, caspase­3, p53, B­cell lymphoma 2 and Bcl­2­associated X protein were determined. These inflammatory, apoptotic, and oxidative stress markers were substantially increased in injured cells, and returned to normal levels following taurine supplementation. Thus, taurine supplementation may be effective against oxidative stress, apoptosis, and inflammation in injured brain cells.


Assuntos
Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Inflamação/tratamento farmacológico , Taurina/farmacologia , Acetilcolinesterase/metabolismo , Animais , Antioxidantes/química , Apoptose/efeitos dos fármacos , Astrócitos/química , Astrócitos/efeitos dos fármacos , Encéfalo/patologia , Catalase/metabolismo , Técnicas de Cocultura , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/patologia , Malondialdeído/metabolismo , Neurônios/química , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Piranos/toxicidade , Ratos , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sulfidrila/toxicidade , Superóxido Dismutase/metabolismo , Taurina/química , Proteína X Associada a bcl-2/genética
17.
Nat Commun ; 9(1): 1561, 2018 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-29674746

RESUMO

Gold deposition with diagonal angle towards boehmite-based nanostructure creates random arrays of horse-bean-shaped nanostructures named gold-nanofève (GNF). GNF generates many electromagnetic hotspots as surface-enhanced Raman spectroscopy (SERS) excitation sources, and enables large-area visualization of molecular vibration fingerprints of metabolites in human cancer xenografts in livers of immunodeficient mice with sufficient sensitivity and uniformity. Differential screening of GNF-SERS signals in tumours and those in parenchyma demarcated tumour boundaries in liver tissues. Furthermore, GNF-SERS combined with quantum chemical calculation identified cysteine-derived glutathione and hypotaurine (HT) as tumour-dominant and parenchyma-dominant metabolites, respectively. CD44 knockdown in cancer diminished glutathione, but not HT in tumours. Mechanisms whereby tumours sustained HT under CD44-knockdown conditions include upregulation of PHGDH, PSAT1 and PSPH that drove glycolysis-dependent activation of serine/glycine-cleavage systems to provide one-methyl group for HT synthesis. HT was rapidly converted into taurine in cancer cells, suggesting that HT is a robust anti-oxidant for their survival under glutathione-suppressed conditions.


Assuntos
Antioxidantes/química , Antioxidantes/metabolismo , Ouro/química , Nanopartículas Metálicas/química , Neoplasias/metabolismo , Análise Espectral Raman/métodos , Taurina/análogos & derivados , Animais , Feminino , Glutationa/metabolismo , Ouro/metabolismo , Humanos , Fígado/química , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Neoplasias/genética , Análise Espectral Raman/instrumentação , Taurina/química , Taurina/metabolismo , Transaminases/genética , Transaminases/metabolismo
18.
Mol Ther ; 26(2): 648-658, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29396265

RESUMO

Most of the peptides used for promoting cellular uptake bear positive charges. In our previous study, we reported an example of taurine (bearing negative charges in physiological conditions) promoting cellular uptake of D-peptides. Taurine, conjugated to a small D-peptide via an ester bond, promotes the cellular uptake of this D-peptide. Particularly, intracellular carboxylesterase (CES) instructs the D-peptide to self-assemble and to form nanofibers, which largely disfavors efflux and further enhances the intracellular accumulation of the D-peptide, as supported by that the addition of CES inhibitors partially impaired cellular uptake of this molecule in mammalian cell lines. Using dynamin 1, 2, and 3 triple knockout (TKO) mouse fibroblasts, we demonstrated that cells took up this molecule via macropinocytosis and dynamin-dependent endocytosis. Imaging of Drosophila larval blood cells derived from endocytic mutants confirmed the involvement of multiple endocytosis pathways. Electron microscopy (EM) indicated that the precursors can form aggregates on the cell surface to facilitate the cellular uptake via macropinocytosis. EM also revealed significantly increased numbers of vesicles in the cytosol. This work provides new insights into the cellular uptake of taurine derivative for intracellular delivery and self-assembly of D-peptides.


Assuntos
Dinaminas/metabolismo , Endocitose/efeitos dos fármacos , Peptídeos/farmacologia , Pinocitose/efeitos dos fármacos , Taurina , Animais , Transporte Biológico , Linhagem Celular , Imunofluorescência , Células HeLa , Humanos , Estrutura Molecular , Peptídeos/química , Transdução de Sinais/efeitos dos fármacos , Taurina/química
19.
Acta Pharmacol Sin ; 39(3): 382-392, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29072257

RESUMO

Short QT syndrome (SQTS) is a genetic arrhythmogenic disease that can cause malignant arrhythmia and sudden cardiac death. The current therapies for SQTS have application restrictions. We previously found that Mg· (NH2CH2CH2SO3)2· H2O, a taurine-magnesium coordination compound (TMCC) exerted anti-arrhythmic effects with low toxicity. In this study we established 3 different models to assess the potential anti-arrhythmic effects of TMCC on type 2 short QT syndrome (SQT2). In Langendorff guinea pig-perfused hearts, perfusion of pinacidil (20 µmol/L) significantly shortened the QT interval and QTpeak and increased rTp-Te (P<0.05 vs control). Subsequently, perfusion of TMCC (1-4 mmol/L) dose-dependently increased the QT interval and QTpeak (P<0.01 vs pinacidil). TMCC perfusion also reversed the rTp-Te value to the normal range. In guinea pig ventricular myocytes, perfusion of trapidil (1 mmol/L) significantly shortened the action potential duration at 50% (APD50) and 90% repolarization (APD90), which was significantly reversed by TMCC (0.01-1 mmol/L, P<0.05 vs trapidil). In HEK293 cells that stably expressed the outward delayed rectifier potassium channels (IKs), perfusion of TMCC (0.01-1 mmol/L) dose-dependently inhibited the IKs current with an IC50 value of 201.1 µmol/L. The present study provides evidence that TMCC can extend the repolarization period and inhibit the repolarizing current, IKs, thereby representing a therapeutic candidate for ventricular arrhythmia in SQT2.


Assuntos
Arritmias Cardíacas/prevenção & controle , Complexos de Coordenação/farmacologia , Sistema de Condução Cardíaco/anormalidades , Cardiopatias Congênitas/prevenção & controle , Magnésio/farmacologia , Taurina/farmacologia , Potenciais de Ação/efeitos dos fármacos , Animais , Arritmias Cardíacas/induzido quimicamente , Células Cultivadas , Cobaias , Cardiopatias Congênitas/induzido quimicamente , Humanos , Magnésio/química , Modelos Teóricos , Miócitos Cardíacos/fisiologia , Pinacidil/antagonistas & inibidores , Pinacidil/farmacologia , Taurina/química , Trapidil/antagonistas & inibidores , Trapidil/farmacologia
20.
J Med Chem ; 60(21): 9003-9011, 2017 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-29048889

RESUMO

Oxaliplatin (OXA) is a valuable and largely used cancer drug which induces a serious and intractable neuropathy. The lipoyl-homotaurine derivative (ADM_12) reverts in vivo OXA-induced neuropathy, and it is an effective antagonist of the nociceptive sensor channel TRPA1. Unprecedentedly, this safe analgesic showed a synergy with OXA in vitro and proved to inhibit CA IX, a relevant therapeutic target, clearly interfering with pancreatic cancer cells' aggressiveness.


Assuntos
Anidrase Carbônica IX/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Compostos Organoplatínicos/toxicidade , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Taurina/análogos & derivados , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Inibidores da Anidrase Carbônica/farmacologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Humanos , Neoplasias/complicações , Neoplasias/patologia , Compostos Organoplatínicos/uso terapêutico , Oxaliplatina , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Canal de Cátion TRPA1/antagonistas & inibidores , Taurina/química , Taurina/farmacologia
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