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1.
Nature ; 631(8020): 319-327, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38898275

RESUMEN

Naturally occurring (native) sugars and carbohydrates contain numerous hydroxyl groups of similar reactivity1,2. Chemists, therefore, rely typically on laborious, multi-step protecting-group strategies3 to convert these renewable feedstocks into reagents (glycosyl donors) to make glycans. The direct transformation of native sugars to complex saccharides remains a notable challenge. Here we describe a photoinduced approach to achieve site- and stereoselective chemical glycosylation from widely available native sugar building blocks, which through homolytic (one-electron) chemistry bypasses unnecessary hydroxyl group masking and manipulation. This process is reminiscent of nature in its regiocontrolled generation of a transient glycosyl donor, followed by radical-based cross-coupling with electrophiles on activation with light. Through selective anomeric functionalization of mono- and oligosaccharides, this protecting-group-free 'cap and glycosylate' approach offers straightforward access to a wide array of metabolically robust glycosyl compounds. Owing to its biocompatibility, the method was extended to the direct post-translational glycosylation of proteins.


Asunto(s)
Técnicas de Química Sintética , Oligosacáridos , Azúcares , Radicales Libres/química , Radicales Libres/metabolismo , Glicosilación/efectos de la radiación , Indicadores y Reactivos/química , Luz , Oligosacáridos/síntesis química , Oligosacáridos/química , Oligosacáridos/metabolismo , Oligosacáridos/efectos de la radiación , Estereoisomerismo , Azúcares/síntesis química , Azúcares/química , Azúcares/metabolismo , Azúcares/efectos de la radiación
2.
Nature ; 615(7950): 67-72, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36603811

RESUMEN

Pyridines and related N-heteroarenes are commonly found in pharmaceuticals, agrochemicals and other biologically active compounds1,2. Site-selective C-H functionalization would provide a direct way of making these medicinally active products3-5. For example, nicotinic acid derivatives could be made by C-H carboxylation, but this remains an elusive transformation6-8. Here we describe the development of an electrochemical strategy for the direct carboxylation of pyridines using CO2. The choice of the electrolysis setup gives rise to divergent site selectivity: a divided electrochemical cell leads to C5 carboxylation, whereas an undivided cell promotes C4 carboxylation. The undivided-cell reaction is proposed to operate through a paired-electrolysis mechanism9,10, in which both cathodic and anodic events play critical roles in altering the site selectivity. Specifically, anodically generated iodine preferentially reacts with a key radical anion intermediate in the C4-carboxylation pathway through hydrogen-atom transfer, thus diverting the reaction selectivity by means of the Curtin-Hammett principle11. The scope of the transformation was expanded to a wide range of N-heteroarenes, including bipyridines and terpyridines, pyrimidines, pyrazines and quinolines.


Asunto(s)
Dióxido de Carbono , Electroquímica , Pirazinas , Piridinas , Pirimidinas , Quinolinas , Hidrógeno/química , Pirazinas/química , Piridinas/química , Pirimidinas/química , Electroquímica/métodos , Dióxido de Carbono/química , Quinolinas/química , Preparaciones Farmacéuticas/síntesis química , Preparaciones Farmacéuticas/química
3.
J Am Chem Soc ; 146(15): 10274-10280, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38568080

RESUMEN

The construction of C(sp3)-C(sp3) bonds remains one of the most difficult challenges in cross-coupling chemistry. Here, we report a photoredox/nickel dual catalytic approach that enables the simultaneous formation of two C(sp3)-C(sp3) linkages via trimolecular cross-coupling of alkenes with alkyl halides and hypervalent iodine-based reagents. The reaction harnesses a bimolecular homolytic substitution (SH2) mechanism and chemoselective halogen-atom transfer (XAT) to orchestrate the regioselective addition of electrophilic and nucleophilic alkyl radicals across unactivated alkenes without the need for a directing auxiliary. Utility is highlighted through late-stage (fluoro)alkylation and (trideutero)methylation of C═C bonds bearing different substitution patterns, offering straightforward access to drug-like molecules comprising sp3-hybridized carbon scaffolds.

4.
Psychol Health Med ; 28(9): 2462-2473, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37126569

RESUMEN

Postpartum depression (PPD) is a major public health problem that has negative effects on mothers, infants, and society. This study was aimed at investigating the prevalence of PPD and elucidating the delivery factors implicated in PPD so as take more targeted measures for reducing the potential risk factors. A prospective cohort study was conducted. Following the criterion, 151 pregnant women were included in the study. The Edinburgh Postpartum Depression Scale (EPDS) and the general questionnaire were filled out 2-3 days after delivery. At weeks 2 and 6 postpartum, the EPDS was reassessed either online or via telephone. Also, electronic medical records based on relevant information during the delivery period were collected. Statistical significance was defined as p < 0.05. A high rate of PPD (31.13%) was reported. Univariate correlation analysis showed statistically significant differences in the husband-wife relationship (χ2 = 18.497, p < 0.001), neonatal health (χ2 = 14.710, p < 0.001), and breast milk volume (χ2 = 5.712, p = 0.017) between PPD and normal control groups. Adjusting for other covariates, multivariate logistic regression analysis showed that satisfactory conjugal relation could reduce the risk of PPD (OR, 0.053; p = 0.022); Neonatal health problems significantly increase the risk of PPD (OR, 6.497; p = 0.001); Adequate breast milk could alleviate the risk of PPD (OR, 0.351; P = 0.045). Data analysis suggests that marital discord and unhealthy new-born are independent risk factors; nevertheless, sufficient breast milk is a protective factor against PPD. Healthcare workers such as hospital and community doctors and social workers should pay attention to PPD. Furthermore, perinatal emotional support, health education, and EPDS assessment need to be incorporated into maternity care. Screening and personalized psychological counselling should be carried out for high-risk pregnant women with PPD.


Asunto(s)
Depresión Posparto , Servicios de Salud Materna , Recién Nacido , Femenino , Embarazo , Humanos , Depresión Posparto/epidemiología , Depresión Posparto/psicología , Esposos , Leche Humana , Estudios Prospectivos , Salud del Lactante , Factores de Riesgo , Periodo Posparto
5.
Angew Chem Int Ed Engl ; 62(23): e202301892, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37010979

RESUMEN

Carboxylation of easily available alkenes with CO2 is highly important to afford value-added carboxylic acids. Although dicarboxylation of activated alkenes, especially 1,3-dienes, has been widely investigated, the challenging dicarboxylation of unactivated 1,n-dienes (n>3) with CO2 remains unexplored. Herein, we report the first dicarboxylation of unactivated skipped dienes with CO2 via electrochemistry, affording valuable dicarboxylic acids. Control experiments and DFT calculations support the single electron transfer (SET) reduction of CO2 to its radical anion, which is followed by sluggish radical addition to unactivated alkenes, SET reduction of unstabilized alkyl radicals to carbanions and nucleophilic attack on CO2 to give desired products. This reaction features mild reaction conditions, broad substrate scope, facile derivations of products and promising application in polymer chemistry.

6.
J Am Chem Soc ; 144(5): 2062-2068, 2022 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-35084189

RESUMEN

Diacids are important monomers in the polymer industry to construct valuable materials. Dicarboxylation of unsaturated bonds, such as alkenes and alkynes, with CO2 has been demonstrated as a promising synthetic method. However, dicarboxylation of C─C single bonds with CO2 has rarely been investigated. Herein we report a novel electrochemical ring-opening dicarboxylation of C─C single bonds in strained rings with CO2. Structurally diverse glutaric acid and adipic acid derivatives were synthesized from substituted cyclopropanes and cyclobutanes in moderate to high yields. In contrast to oxidative ring openings, this is also the first realization of an electroreductive ring-opening reaction of strained rings, including commercialized ones. Control experiments suggested that radical anions and carbanions might be the key intermediates in this reaction. Moreover, this process features high step and atom economy, mild reaction conditions (1 atm, room temperature), good chemoselectivity and functional group tolerance, low electrolyte concentration, and easy derivatization of the products. Furthermore, we conducted polymerization of the corresponding diesters with diols to obtain a potential UV-shielding material with a self-healing function and a fluorine-containing polyester, whose performance tests showed promising applications.

7.
J Am Chem Soc ; 143(7): 2812-2821, 2021 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-33561344

RESUMEN

Carboxylic acids, including amino acids (AAs), have been widely used as reagents for decarboxylative couplings. In contrast to previous decarboxylative couplings that release CO2 as a waste byproduct, herein we report a novel strategy with simultaneous utilization of both the alkyl and carboxyl components from carboxylic acids. Under this unique strategy, carboxylic acids act as bifunctional reagents in the redox-neutral carbocarboxylation of alkenes. Diverse, inexpensive, and readily available α-AAs take part in such difunctionalizations of activated alkenes via visible-light photoredox catalysis, affording a variety of valuable but otherwise difficult to access γ-aminobutyric acid derivatives (GABAs). Additionally, a series of dipeptides and tripeptides also participate in this photocatalytic carbocarboxylation. Although several challenges exist in this system due to the low concentration and quantitative amount of CO2, as well as unproductive side reactions such as hydrodecarboxylation of the carboxylic acids and hydroalkylation of the alkenes, excellent regioselectivity and moderate to high chemoselectivity are achieved. This process features low catalyst loading, mild reaction conditions, high step and atom economy, and good functional group tolerance, and it is readily scalable. The resulting products are subject to efficient derivations, and the overall process is amenable to applications in the late-stage modification of complex compounds. Mechanistic studies indicate that a carbanion is generated catalytically and it acts as the key intermediate to react with CO2, which is also generated catalytically in situ and thus remains in low concentration. The overall transformation represents an efficient and sustainable system for organic synthesis, pharmaceutics, and biochemistry.


Asunto(s)
Alquenos/química , Aminoácidos/química , Dióxido de Carbono/química , Péptidos/química , Ácidos Carboxílicos/química , Luz , Ácido gamma-Aminobutírico/química
8.
Mycopathologia ; 185(6): 975-982, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32989583

RESUMEN

Although Meyerozyma guilliermondii complex is an uncommon cause of invasive candidiasis worldwide, reported cases, mainly regarding bloodstream infections, increased over years, and patients with cancer who have undergone recent surgery are most commonly affected. However, the clinical characteristics and outcomes of candidemia caused by M. guilliermondii complex remain poorly understood. A retrospective case-control study was conducted to evaluate the clinical characteristics and mortality of candidemia caused by M. guilliermondii complex in cancer patients undergoing surgery. Demographic and clinical data were collected from the hospital medical records system with a standardized data collection form and were analyzed with SPSS 20.0. Sixty-six cancer patients who have undergone recent surgery and were diagnosed with candidemia caused by M. guilliermondii complex were included in the study. Regarding the clinical manifestations, most patients' body temperatures ranged from 38 to 40 °C, with a median fever duration of 4 (IQR: 3-6) days. Multivariate analysis indicated that the presence of central venous catheter (OR: 6.68; 95% CI 2.80-15.94) and gastric tube (OR: 3.55; 95% CI 1.22-10.34) were independent risk factors for M. guilliermondii complex fungemia. The 30-day crude mortality of candidemia caused by M. guilliermondii complex was 12.1%, twice that of the control group. Moreover, increased WBC count, age ≥ 60 years, septic shock, and ICU admission were identified as predictors of mortality through univariate analysis. These findings will provide a foundation for the clinical management of candidemia caused by M. guilliermondii complex in post-surgical cancer patients.


Asunto(s)
Candidemia , Neoplasias , Saccharomycetales/patogenicidad , Antifúngicos/uso terapéutico , Candidemia/tratamiento farmacológico , Estudios de Casos y Controles , Fungemia/tratamiento farmacológico , Humanos , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/cirugía , Estudios Retrospectivos , Factores de Riesgo
9.
J Cell Physiol ; 234(7): 11734-11745, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30536938

RESUMEN

Subacute ruminal acidosis (SARA) is characterized by the depression of ruminal pH and an increase in the concentrations of short-chain fatty acids (SCFAs) and lipopolysaccharide (LPS) in the rumen of cows. The onset of SARA was linked to the accumulation of SCFAs. However, the mechanism of SCFAs transport is unknown. The proton-linked monocarboxylate transporter (MCT1) plays a vital role in the transportation of SCFAs. The goal of this study was to elucidate the distribution of MCT1 along the gastrointestinal tract of calves and adult cows; the expression change of MCT1 in SARA cows and the effect of ruminal pH, SCFAs, and LPS on MCT1 expression in rumen epithelial cells in vitro. The results indicated the presence of MCT1 along the gastrointestinal tract of calves and adult cows, most abundantly expressed in the rumen. Importantly, the expression of MCT1 was decreased in the rumen epithelium of SARA cows, and the expression of MCT1 was restored in the SARA treatment group. In vitro, LPS, low rumen fluid pH, high concentrations of SCFAs (90 mM acetate, 40 mM propionate, and 30 mM butyrate), and high concentrations of acetate, propionate, and butyrate, respectively, inhibited the expression of MCT1 in rumen epithelial cells. Taken together, these results indicated that LPS, low ruminal pH, and high concentrations of SCFAs decreased the expression of MCT1, further aggravating the accumulation of SCFAs in the rumen by decreasing the absorption of SCFAs.


Asunto(s)
Acidosis/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Rumen/metabolismo , Simportadores/metabolismo , Animales , Bovinos , Supervivencia Celular/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Epitelio/efectos de los fármacos , Epitelio/metabolismo , Ácidos Grasos Volátiles/metabolismo , Femenino , Concentración de Iones de Hidrógeno , Lipopolisacáridos/farmacología , Transporte de Proteínas/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Rumen/efectos de los fármacos
10.
J Dairy Res ; 86(1): 73-76, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30819264

RESUMEN

Dairy cows with fatty liver or ketosis display decreased insulin sensitivity and defects in the insulin receptor substrate (IRS)/PI3K/AKT signaling pathway. Phosphatase and tensin homolog (PTEN) is a well-known tumor suppressor and also a negative regulator of insulin signaling and peripheral insulin sensitivity. We investigated the hypothesis that PTEN may affect the insulin pathway-mediated hepatic glucose and lipid metabolism in dairy cows. Adenovirus vectors that over-express and silence PTEN were constructed, and then transfected into hepatocytes isolated from calves to investigate the effect of PTEN on PI3K/AKT signaling pathway. PTEN silencing increased the phosphorylation of AKT and the expression of PI3K but decreased the phosphorylation of IRS1, which increased the phosphorylation levels of glycogen synthase kinase-3ß (GSK-3ß) and expression of sterol regulatory element-binding protein-1c (SREBP-1c). Increased GSK-3ß phosphorylation further up-regulated expression of the key enzymes phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6-Pase) involved in gluconeogenesis. Furthermore, the expression of SREBP-1c target gene fatty acid synthase (FAS) also increased significantly. We further showed that PTEN over-expression could reverse the above results. PTEN negatively regulates the enzymes involved in hepatic gluconeogenesis and lipid synthesis, which suggests that PTEN may be a therapeutic target for ketosis and fatty liver in dairy cows.


Asunto(s)
Bovinos , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Insulina/metabolismo , Metabolismo de los Lípidos/fisiología , Fosfohidrolasa PTEN/fisiología , Animales , Femenino , Expresión Génica/efectos de los fármacos , Expresión Génica/fisiología , Gluconeogénesis/efectos de los fármacos , Gluconeogénesis/fisiología , Glucosa/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/farmacocinética , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Transfección
11.
J Dairy Res ; 86(2): 171-176, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31142385

RESUMEN

Subacute ruminal acidosis (SARA) can increase the level of inflammation and induce rumenitis in dairy cows. Berberine (BBR) is the major active component of Rhizoma Coptidis, which is a type of Chinese anti-inflammatory drug for gastrointestinal diseases. The purpose of this study was to investigate the anti-inflammatory effects of BBR on lipopolysaccharide (LPS)-stimulated rumen epithelial cells (REC) and the underlying molecular mechanisms. REC were cultured and stimulated with LPS in the presence or absence of different concentrations of BBR. The results showed that cell viability was not affected by BBR. Moreover, BBR markedly decreased the concentrations and mRNA expression of pro-inflammatory cytokines, including tumor necrosis factor-α, interleukin-1ß, and interleukin-6 in the LPS-treated REC in a dose-dependent manner. Importantly, Western blotting analysis showed that BBR significantly suppressed the protein expression of toll-like receptor 4 (TLR4) and myeloid differentiation primary response protein (MyD88) and the phosphorylation of nuclear factor-κB (NF-κB), inhibitory kappa B (IκBα), p38 mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (JNK) in LPS-treated REC. Furthermore, the results of immunocytofluorescence showed that BBR significantly inhibited the nuclear translocation of NF-κB p65 induced by LPS treatment. In conclusion, the protective effects of BBR on LPS-induced inflammatory responses in REC may be due to its ability to suppress the TLR4-mediated NF-κB and MAPK signaling pathways. These findings suggest that BBR can be used as an anti-inflammatory drug to treat inflammation induced by SARA.


Asunto(s)
Berberina/farmacología , Citocinas/metabolismo , Lipopolisacáridos/toxicidad , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Bovinos , Citocinas/genética , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , FN-kappa B/genética , Rumen , Receptor Toll-Like 4/genética
12.
J Am Chem Soc ; 140(50): 17338-17342, 2018 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-30518213

RESUMEN

Cross-electrophile couplings between two electrophiles are powerful and economic methods to generate C-C bonds in the presence of stoichiometric external reductants. Herein, we report a novel strategy to realize the first external-reductant-free cross-electrophile coupling via visible-light photoredox catalysis. A variety of tetraalkyl ammonium salts, bearing primary, secondary, and tertiary C-N bonds, undergo selective couplings with aldehydes/ketone and CO2. Notably, the in situ generated byproduct, trimethylamine, is efficiently utilized as the electron donor. Moreover, this protocol exhibits mild reaction conditions, low catalyst loading, broad substrate scope, good functional group tolerance, and facile scalability. Mechanistic studies indicate that benzyl radicals and anions might be generated as the key intermediates via photocatalysis, providing a new direction for cross-electrophile couplings.

13.
BMC Vet Res ; 14(1): 135, 2018 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-29673406

RESUMEN

BACKGROUND: Subacute ruminal acidosis (SARA) is a metabolic disease in high-producing dairy cattle, and is accompanied by rumenitis. However, the mechanism of rumenitis remains unclear. Therefore, the aim of this study was to investigate the molecular mechanism of rumenitis in dairy cows with SARA. RESULTS: The results showed that SARA cows displayed high concentrations of ruminal volatile fatty acids, lactic acid and lipopolysaccharide (LPS). Furthermore, the blood concentrations of LPS and acute phase proteins haptoglobin, serum amyloid-A, and LPS binding protein were significantly higher in SARA cows than in control cows. Importantly, the phosphorylation levels of nuclear factor-kappaB (NF-κB) p65, inhibitor of NF-κB (IκB), c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase 1/2 (ERK1/2) were significantly higher in the rumen epithelium of SARA cows than those of control cows. The ruminal mRNA and protein levels of NF-κB- and mitogen-activated protein kinase (MAPK)s -regulated inflammatory cytokines, tumor necrosis factor α (TNF-α), interleukin 6 (IL-6) and interleukin 1ß (IL-1ß), were markedly higher in SARA cows than in control cows. Similarly, serum concentrations of TNF-α and IL-6 were also significantly higher in SARA cows. CONCLUSIONS: These results indicate that SARA results in high concentration of ruminal LPS, which over activates the NF-κB and MAPKs inflammatory pathways and then significantly increases the expression and synthesis of pro-inflammation cytokines in the rumen epithelium, thereby partly inducing rumenitis.


Asunto(s)
Acidosis/veterinaria , Gastritis/veterinaria , Inflamación/veterinaria , Rumen/inmunología , Acidosis/sangre , Acidosis/inmunología , Acidosis/metabolismo , Proteínas de Fase Aguda/análisis , Proteínas de Fase Aguda/metabolismo , Animales , Bovinos , Ácidos Grasos Volátiles/metabolismo , Femenino , Mucosa Gástrica/metabolismo , Gastritis/sangre , Gastritis/inmunología , Gastritis/metabolismo , Haptoglobinas/análisis , Inflamación/inmunología , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Ácido Láctico/metabolismo , Lipopolisacáridos/sangre , Lipopolisacáridos/metabolismo , FN-kappa B/metabolismo , Proteína Amiloide A Sérica/análisis , Factor de Necrosis Tumoral alfa/metabolismo
14.
Cell Physiol Biochem ; 42(3): 1109-1119, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28668950

RESUMEN

BACKGROUND/AIMS: Subacute ruminal acidosis (SARA) is a common disease in high-producing lactating cows. Rumenitis is the initial insult of SARA and is associated with the high concentrations of histamine produced in the rumen of dairy cows during SARA. However, the exact mechanism remains unclear. The objective of the current study is to investigate whether histamine induces inflammation of rumen epithelial cells and the underlying mechanism of this process. METHODS: Bovine rumen epithelial cells were cultured and treated with different concentrations of histamine and pyrrolidine dithiocarbamate (PDTC, an NF-κB inhibitor) cultured in different pH medium (pH 7.2 or 5.5). qRT-PCR, Western-blotting, ELISA and immunocytofluorescence were used to evaluate whether histamine activated the NF-κB pathway and inflammatory cytokines. RESULTS: The results showed that histamine significantly increased the activity of IKK ß and the phosphorylation levels of IκB α, as well as upregulated the mRNA and protein expression levels of NF-κB p65 in the rumen epithelial cells cultured in neutral (pH=7.2) and acidic (pH=5.5) medium. Furthermore, histamine treatment also significantly increased the transcriptional activity of NF-κB p65. High expression and transcriptional activity of NF-κB p65 significantly increased the mRNA expressions and concentrations of inflammatory cytokines, tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 1 beta (IL-1ß), thereby inducing the inflammatory response in bovine rumen epithelial cells. However, inhibition of NF-κB p65 by PDTC significantly decreased the expressions and concentrations of the inflammatory cytokines induced by histamine in the rumen epithelial cells cultured in the neutral and acidic medium. CONCLUSION: The present data indicate that histamine induces the inflammatory response of bovine rumen epithelial cells through the NF-κB pathway.


Asunto(s)
Acidosis/veterinaria , Enfermedades de los Bovinos/inmunología , Bovinos/inmunología , Histamina/inmunología , Inflamación/veterinaria , FN-kappa B/inmunología , Rumen/inmunología , Acidosis/genética , Acidosis/inmunología , Animales , Bovinos/genética , Enfermedades de los Bovinos/genética , Citocinas/genética , Citocinas/inmunología , Células Epiteliales/inmunología , Células Epiteliales/metabolismo , Femenino , Regulación de la Expresión Génica , Inflamación/genética , Inflamación/inmunología , Lactancia , FN-kappa B/genética , Rumen/citología , Rumen/metabolismo , Transducción de Señal
15.
J Cell Biochem ; 116(6): 1070-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25558823

RESUMEN

ß-hydroxybutyric acid (BHBA), an important metabolite in ß-oxidation, is involved in the development of ketosis in dairy cows. It is known that AMP-activated protein kinase (AMPK) signaling pathway plays an important role in the regulation of lipid metabolism in hepatocytes. In the present study, bovine hepatocytes were treated with BHBA at variable concontrations and Compound C (Cpd C, an AMPK inhibitor) to investigate the effects of BHBA on the AMPK signaling pathway. The results showed that when the concentration of BHBA reached 1.2 mM, the AMPK signaling pathway was activated and the expression of sterol regulatory element binding protein-1c (SREBP-1c) as well as its target genes were significantly decreased. And these decreases were blocked by Cpd C. The binding activity and nucleus translocation of SREBP-1c showed a similar trend. The expression of peroxisome proliferator activated receptor-α (PPARα), carbohydrates response element binding protein (ChREBP) and their target genes were significantly increased while they were negatively suppressed by the Cpd C. The content of triglyceride (TG) had no obviously change in the BHBA and Cpd C-treated groups. These results indicate that BHBA can activate AMPK signaling pathway and regulate lipid synthesis and lipid oxidation genes of AMPK but showed no effect on TG in bovine hepatocytes.


Asunto(s)
Ácido 3-Hidroxibutírico/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Proteínas Quinasas Activadas por AMP/genética , Animales , Bovinos , Células Cultivadas , Hepatocitos/citología , Transducción de Señal/efectos de los fármacos , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo
16.
Cell Physiol Biochem ; 33(5): 1568-78, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24854845

RESUMEN

BACKGROUND: Fatty liver is a major metabolic disorder that occurs during early lactation in high-producing dairy cows. Sterol regulatory element-binding protein-1c (SREBP-1c) is an important transcription factor that regulates lipid synthesis by regulating the expression of lipid metabolism genes. METHODS: In this study, we reduced the expression of SREBP-1c by adenovirus-mediated SREBP-1c with a low expression vector (AD-GFP-SREBP-1c) to study the effects of SREBP-1c on lipid deposits in bovine hepatocytes. The expression levels and enzyme activities of SERBP-1c and its target genes were determined by real-time PCR, western blot, and ELISA. RESULTS: These results showed that Ad-GFP-SREBP-1c could inhibit SREBP-1c expression. The expression of the lipid synthesis enzyme acetyl-CoA carboxylase (ACC) was down-regulated. The expression levels of the lipid oxidation enzymes long-chain fatty acyl-COA synthetase (ACSL-1), carnitine palmitoyltransferase І (CPT-І), carnitine palmitoyltransferase II (CPT- II), and ß-hydroxyacyl-CoA-DH (HADH) were significantly elevated. Furthermore, the expression levels of factors involved in the assembly and transport of very low-density lipoproteins (VLDLs), such as apolipoprotein B100 (ApoB), apolipoprotein E (ApoE), and microsomal triglyceride transfer protein (MTTP) were decreased comparison with the negative control and the blank control groups, but the low-density lipoprotein receptor (LDLR) was elevated. The concentrations of TG (triglyceride) and VLDL were also reduced. CONCLUSION: These data suggest that low SREBP-1c expression can decrease lipid synthesis, increase lipid oxidation, and decrease the TG and VLDL content in bovine hepatocytes.


Asunto(s)
Silenciador del Gen , Hepatocitos/citología , Hepatocitos/metabolismo , Metabolismo de los Lípidos , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/deficiencia , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Adenoviridae/metabolismo , Animales , Bovinos , Células Cultivadas , Perfilación de la Expresión Génica , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo
17.
Inflamm Res ; 63(6): 429-39, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24487736

RESUMEN

OBJECTIVE: We investigated whether p-synephrine exerts potent anti-inflammatory effects against acute lung injury (ALI) induced by lipopolysaccharide (LPS) in vivo, and we further investigated the inhibitory mechanism of p-synephrine in LPS-induced ALI. METHODS: Lipopolysaccharide (0.5 mg/kg) was instilled intranasally in phosphate-buffered saline to induce acute lung injury, and 6, 24, and 48 h after LPS was given, bronchoalveolar lavage fluid was obtained to measure pro-inflammatory mediator. We also evaluated the effects of p-synephrine on LPS-induced the severity of pulmonary injury. The phosphorylation of nuclear factor-κB (NF-κB) p65 protein was analyzed by Western blotting. RESULTS: Our data showed that p-synephrine significantly reduced the amount of inflammatory cells, the lung wet-to-dry weight (W/D) ratio, reactive oxygen species, myeloperoxidase activity and enhanced superoxide dismutase (SOD) in mice with LPS-induced ALI. Tumor necrosis factor α and interleukin (IL)-6 concentrations decreased significantly while the concentration of IL-10 was significantly increased after p-synephrine pretreatment. In addition, p-synephrine suppressed not only the phosphorylation of NF-κB but also the degradation of its inhibitor (IκBα). CONCLUSIONS: These results suggested that the inhibition of NF-κB activation and the regulation of SOD are involved in the mechanism of p-synephrine's protection against ALI.


Asunto(s)
Lesión Pulmonar Aguda/inmunología , Antiinflamatorios/farmacología , FN-kappa B/antagonistas & inhibidores , Sinefrina/farmacología , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/tratamiento farmacológico , Lesión Pulmonar Aguda/patología , Animales , Antiinflamatorios/uso terapéutico , Líquido del Lavado Bronquioalveolar/citología , Líquido del Lavado Bronquioalveolar/inmunología , Recuento de Células , Interleucina-10/inmunología , Interleucina-6/inmunología , Lipopolisacáridos , Pulmón/efectos de los fármacos , Pulmón/inmunología , Pulmón/patología , Masculino , Ratones Endogámicos BALB C , FN-kappa B/inmunología , Peroxidasa/inmunología , Especies Reactivas de Oxígeno/inmunología , Superóxido Dismutasa/inmunología , Sinefrina/uso terapéutico , Factor de Necrosis Tumoral alfa/inmunología
18.
J Surg Res ; 186(1): 436-45, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24120240

RESUMEN

BACKGROUND: Bornyl acetate is a bicyclic monoterpene present in numerous conifer oils. In this study, we aimed at clarifying the potential anti-inflammatory function and mechanism of bornyl acetate by using lipopolysaccharide (LPS)-induced acute lung injury murine model and RAW 264.7 cells. MATERIALS AND METHODS: RAW 264.7 cells were pretreated with bornyl acetate 1 h before LPS stimulation and cell-free super supernatants were collected to measure cytokine concentrations. To induce acute lung injury, BALB/c mice were injected intranasally with LPS and treated with bornyl acetate 1 h before LPS stimulation. Seven hours after administration, the bronchoalveolar lavage fluid (BALF) was collected for measuring the cell count and cytokine production. We collected lungs for assaying wet-to-dry weight ratio, myeloperoxidase activity, and histologic changes. The extent of phosphorylation of mitogen-activated protein kinases and nuclear factor κB was detected by Western blot. RESULTS: Our results showed that bornyl acetate downregulated the levels of proinflammatory cytokines in vitro and in vivo; reduced the number of total cells, neutrophils, and macrophages in BALF; attenuated the histologic alterations in the lung; decreased the wet-to-dry weight ratio in BALF; and suppressed NF-kappa-B inhibitor alpha, extracellular regulated protein kinases, c-JunN-terminal kinase, p38 mitogen-activated protein kinase activation. CONCLUSIONS: These findings suggested that bornyl acetate may be developed as a preventive agent for lung inflammatory diseases.


Asunto(s)
Canfanos/farmacología , Peroxidasa/metabolismo , Neumonía/prevención & control , Lesión Pulmonar Aguda/patología , Animales , Células Cultivadas , Citocinas/biosíntesis , Pulmón/efectos de los fármacos , Pulmón/patología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/fisiología , Masculino , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo
19.
J Surg Res ; 185(1): 300-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23816246

RESUMEN

BACKGROUND: Angelicin is a furocoumarin found in Psoralea corylifolia L. fruit. The purpose of this study was to investigate the protective ability of angelicin against inflammation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and LPS-induced in vivo acute lung injury model. MATERIALS AND METHODS: The concentrations of tumor necrosis factor alpha (TNF-α) and interleukin (IL)-6 in the culture supernatants of RAW 264.7 cells were determined 24 h after LPS administration. ALI was induced by intratracheal instillation of LPS. Six hours after LPS inhalation, bronchoalveolar lavage fluid and lung tissue samples were obtained for enzyme-linked immunosorbent assay, histologic, and Western blotting analyses. RESULTS: The results showed that pretreatment with angelicin markedly downregulated TNF-α and IL-6 levels in vitro and in vivo, and significantly decreased the amount of inflammatory cells, lung wet-to-dry weight ratio, and myeloperoxidase activity in LPS-induced ALI mice. Furthermore, Western blotting analysis results demonstrated that angelicin blocked the phosphorylation of IκBα, NF-κBp65, p38 MAPK, and JNK in LPS-induced ALI. CONCLUSIONS: These results suggest that angelicin was potentially advantageous to prevent inflammatory diseases by inhibiting NF-κB and MAPK pathways. Our data indicated that angelicin might be a potential new agent for prevention of inflammatory reactions and diseases in the clinic.


Asunto(s)
Lesión Pulmonar Aguda/tratamiento farmacológico , Furocumarinas/farmacología , Lipopolisacáridos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , FN-kappa B/inmunología , Neumonía/tratamiento farmacológico , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/inmunología , Animales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/inmunología , Modelos Animales de Enfermedad , Furocumarinas/química , Interleucina-6/metabolismo , Sistema de Señalización de MAP Quinasas/inmunología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , FN-kappa B/metabolismo , Neumonía/inducido químicamente , Neumonía/inmunología , Factor de Necrosis Tumoral alfa/metabolismo
20.
Immunopharmacol Immunotoxicol ; 35(4): 514-23, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23844578

RESUMEN

CONTEXT: Acute lung injury (ALI), characterized by severe hypoxemia, pulmonary edema and neutrophil accumulation in the lung, is a common clinical problem associated with significant morbidity and mortality in shock, sepsis, ischemia reperfusion, etc. OBJECTIVE: In this study, we aimed at investigating the protective effect of tubeimoside-1 (TBMS1) on inflammation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and a LPS-induced in vivo lung injury model. MATERIALS AND METHODS: We evaluated the effect of TBMS1 on LPS-induced production of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and IL-1ß in the culture supernatants of RAW 264.7 cells by enzyme-linked immunosorbent assay. LPS (0.5 mg/kg) was instilled intranasally in phosphate-buffered saline to induce ALI, and the severity of pulmonary injury was evaluated 6 h after LPS challenge. RESULTS: TBMS1 significantly inhibited the production of the pro-inflammatory cytokines, TNF-α, IL-6 and IL-1ß in vitro and in vivo. Pretreatment with TBMS1 markedly attenuated the development of pulmonary edema, histological severities and inflammatory cells infiltration in mice with ALI. In addition, we further demonstrated that TBMS1 exerts an anti-inflammatory effect in vivo model of ALI through suppression of IκB activation and p38/extracellular signal-regulated kinase mitogen-activated protein kinases signaling in a dose-dependent manner. DISCUSSION AND CONCLUSION: Overall, our data suggest that TBMS1 inhibits inflammation both in vitro and in vivo, and may be a potential therapeutic candidate for the prevention of inflammatory diseases.


Asunto(s)
Lesión Pulmonar Aguda/prevención & control , Lipopolisacáridos/toxicidad , Macrófagos/inmunología , Edema Pulmonar/prevención & control , Saponinas/farmacología , Triterpenos/farmacología , Lesión Pulmonar Aguda/inducido químicamente , Lesión Pulmonar Aguda/inmunología , Lesión Pulmonar Aguda/patología , Animales , Línea Celular , Citocinas/inmunología , Inflamación/inducido químicamente , Inflamación/inmunología , Inflamación/patología , Inflamación/prevención & control , Macrófagos/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Edema Pulmonar/inducido químicamente , Edema Pulmonar/inmunología , Edema Pulmonar/patología
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