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1.
Phys Chem Chem Phys ; 26(15): 11395-11405, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38572584

RESUMEN

The initial decomposition pathways of α-FOX-7 in the condensed phase (crystal) were investigated via density functional theory. Calculations were carried out using three FOX-7 systems with increasing complexity from 1-layer (sheet) via 2-layer (surface) to 3-layer (bulk). The encapsulated environment of the central α-FOX-7 molecule, where decomposition takes place, is reconstructed by neighbouring molecules following a crystal structure. A minimal number of neighbouring molecules that have an impact on the energetics of decomposition are identified among all surrounding molecules. The results show that the presence of intermolecular hydrogen bonds due to the encapsulated environment in the condensed phase decreases the sensitivity of α-FOX-7, i.e. it increases the barrier of decomposition, but it does not alter the initial decomposition pathways of the reaction compared to the gas phase. Moreover, increasing the complexity of the system from a single gas phase molecule via sheet and surface to bulk increases the decomposition barriers. The calculations reveal a remarkable agreement with experimental data [A. M. Turner, Y. Luo, J. H. Marks, R. Sun, J. T. Lechner, T. M. Klapötke and R. I. Kaiser, Exploring the Photochemistry of Solid 1, 1-Diamino-2, 2-Dinitroethylene (FOX-7) Spanning Simple Bon Ruptures, Nitro-to-Nitrite Isomerization, and Nonadiabatic Dynamics, J. Phys. Chem. A, 2022, 126, 29, 4747-4761] and suggest that the initial decomposition of α-FOX-7 likely takes place at the surface of the crystal.

2.
J Chem Phys ; 160(19)2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38747431

RESUMEN

In this paper, we present a combined experimental and theoretical study that explored the initial sticking of water on cooled surfaces. Specifically, these ultra-high vacuum gas-surface scattering experiments utilized supersonic molecular beam techniques in conjunction with a cryogenically cooled highly oriented pyrolytic graphite crystal, giving control over incident kinematic conditions. The D2O translational energy spanning 300-750 meV, the relative D2O flux, and the incident angle could all be varied independently. Three different experimental measurements were made. One involved measuring the total amount of D2O scattering as a function of surface temperature to determine the onset of sticking under non-equilibrium gas-surface collision conditions. Another measurement used He specular scattering to assess structural and coverage information for the interface during D2O adsorption. Finally, we used time-of-flight (TOF) measurements of the scattered D2O to determine how energy is exchanged with the graphite surface at surface temperatures above and near the conditions needed for gaseous condensation. For comparison and elaboration of the roles that internal degrees of freedom play in this process, we also did similar TOF measurements using another mass 20 incident particle, atomic neon. Enriching this study are precise molecular dynamics simulations that elaborate on gas-surface energy transfer and the roles of molecular degrees of freedom in gas-surface collisional energy exchange processes. This study furthers our fundamental understanding of energy exchange and the onset of sticking and ultimately gaseous condensation for gas-surface encounters occurring under high-velocity flows.

3.
Crit Rev Food Sci Nutr ; 63(7): 862-872, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34292103

RESUMEN

The microbial-derived products, including short chain fatty acids, lipopolysaccharide and secondary bile acids, have been shown to participate in the regulation of hepatic lipid metabolism. Previous studies have demonstrated that prebiotics, such as oligosaccharide and inulin, have abilities to change the concentration of microbial-derived products through modulating the microbial community structure, thus controlling body weight and alleviating hepatic fat accumulation. However, recent evidence indicates that there are individual differences in host response upon inulin treatment due to the differences in host microbial composition before dietary intervention. Probably it is because of the multiple relationships among bacterial species (e.g., competition and mutualism), which play key roles in the degradation of inulin and the regulation of microbial structure. Thereby, analyzing the composition and function of initial gut microbiota is essential for improving the efficacy of prebiotics supplementation. Furthermore, considering that different structures of polysaccharides can be used by different microorganisms, the chemical structure of processed inulin should be tested before using prebiotic inulin to treat obesity related nonalcoholic fatty liver disease.


Asunto(s)
Microbioma Gastrointestinal , Enfermedad del Hígado Graso no Alcohólico , Humanos , Prebióticos , Inulina/farmacología , Inulina/uso terapéutico , Inulina/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Obesidad/complicaciones , Obesidad/tratamiento farmacológico
4.
J Phys Chem A ; 127(15): 3390-3401, 2023 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-37027514

RESUMEN

Solid FOX-7 (1,1-diamino-2,2-dinitroethylene), an energetic material of interest due to its high stability and low shock/thermal sensitivity, was exposed to energetic electrons at 5 K to explore the fundamental mechanisms leading to decomposition products and provide a better understanding of the reaction pathways involved. As a result of the radiation exposure, infrared spectroscopy revealed carbon dioxide (CO2) and carbon monoxide (CO) trapped in the FOX-7 matrix, while these compounds along with water (H2O), nitrogen monoxide (NO), and cyanogen (C2N2) were detected exploiting quadrupole mass spectrometry both during irradiation and during the warming phase from 5 to 300 K. Photoionization reflectron time-of-flight mass spectrometry detected small molecules such as ammonia (NH3), nitrogen monoxide (NO), and nitrogen dioxide (NO2) as well as more complex molecules up to 96 amu. Potential reaction pathways are presented and assignments are discussed. Among the reaction mechanisms, the importance of an initial nitro-to-nitrite isomerization is highlighted by the observed decomposition products.

5.
J Nat Prod ; 86(2): 276-289, 2023 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-36746775

RESUMEN

Sixteen new quinoline alkaloids (1a-7, 8a, 9, 10, 13-15, 17, and 21) and 10 known analogs (8b, 11, 12, 16, 18-20, and 22-24), along with three known cyclopeptide alkaloids (25-27), were isolated from the roots of Waltheria indica. The structures of the new compounds were elucidated by detailed NMR and circular dichroism with computational support and mass spectrometry data interpretation. Anti-inflammatory potential of isolates was evaluated based on inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production and tumor necrosis factor-alpha (TNF-α)-induced nuclear factor kappa B (NF-κB) activity with cell culture models. In the absence of cell growth inhibition, compounds 6, 8a, 9-11, 13, 21, and 24 reduced TNF-α-induced NF-κB activity with IC50 values ranging from 7.1 to 12.1 µM, comparable to the positive control (BAY 11-7082, IC50 = 9.7 µM). Compounds 6, 8a, 8b, and 11 showed significant NO-inhibitory activity with IC50 values ranging from 11.0 to 12.8 µM, being more active than the positive control (l-NMMA, IC50 = 22.7 µM). Structure-activity relationships indicated that NO inhibitory activity was significantly affected by C-8 substitution. Inhibition of LPS-induced nitric oxide synthase (iNOS) by 8b [(5S)-waltherione M, IC50 11.7 ± 0.8 µM] correlated with inhibition of iNOS mRNA expression. The biological potential of W. indica metabolites supports the traditional use of this plant for the treatment of inflammatory-related disorders.


Asunto(s)
Alcaloides , Malvaceae , Quinolinas , FN-kappa B/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Lipopolisacáridos/farmacología , Alcaloides/farmacología , Antiinflamatorios/farmacología , Malvaceae/química , Óxido Nítrico Sintasa de Tipo II/metabolismo , Óxido Nítrico
6.
Proc Natl Acad Sci U S A ; 117(48): 30142-30150, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33199606

RESUMEN

Since the postulation of carbenes by Buchner (1903) and Staudinger (1912) as electron-deficient transient species carrying a divalent carbon atom, carbenes have emerged as key reactive intermediates in organic synthesis and in molecular mass growth processes leading eventually to carbonaceous nanostructures in the interstellar medium and in combustion systems. Contemplating the short lifetimes of these transient molecules and their tendency for dimerization, free carbenes represent one of the foremost obscured classes of organic reactive intermediates. Here, we afford an exceptional glance into the fundamentally unknown gas-phase chemistry of preparing two prototype carbenes with distinct multiplicities-triplet pentadiynylidene (HCCCCCH) and singlet ethynylcyclopropenylidene (c-C5H2) carbene-via the elementary reaction of the simplest organic radical-methylidyne (CH)-with diacetylene (HCCCCH) under single-collision conditions. Our combination of crossed molecular beam data with electronic structure calculations and quasi-classical trajectory simulations reveals fundamental reaction mechanisms and facilitates an intimate understanding of bond-breaking processes and isomerization processes of highly reactive hydrocarbon intermediates. The agreement between experimental chemical dynamics studies under single-collision conditions and the outcome of trajectory simulations discloses that molecular beam studies merged with dynamics simulations have advanced to such a level that polyatomic reactions with relevance to extreme astrochemical and combustion chemistry conditions can be elucidated at the molecular level and expanded to higher-order homolog carbenes such as butadiynylcyclopropenylidene and triplet heptatriynylidene, thus offering a versatile strategy to explore the exotic chemistry of novel higher-order carbenes in the gas phase.

7.
Proc Natl Acad Sci U S A ; 117(37): 22712-22719, 2020 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-32859759

RESUMEN

Complex organosulfur molecules are ubiquitous in interstellar molecular clouds, but their fundamental formation mechanisms have remained largely elusive. These processes are of critical importance in initiating a series of elementary chemical reactions, leading eventually to organosulfur molecules-among them potential precursors to iron-sulfide grains and to astrobiologically important molecules, such as the amino acid cysteine. Here, we reveal through laboratory experiments, electronic-structure theory, quasi-classical trajectory studies, and astrochemical modeling that the organosulfur chemistry can be initiated in star-forming regions via the elementary gas-phase reaction of methylidyne radicals with hydrogen sulfide, leading to thioformaldehyde (H2CS) and its thiohydroxycarbene isomer (HCSH). The facile route to two of the simplest organosulfur molecules via a single-collision event affords persuasive evidence for a likely source of organosulfur molecules in star-forming regions. These fundamental reaction mechanisms are valuable to facilitate an understanding of the origin and evolution of the molecular universe and, in particular, of sulfur in our Galaxy.

8.
Anim Biotechnol ; 34(8): 4021-4031, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37647084

RESUMEN

Grape seed proanthocyanidin extract (GSPE) plays a significant role in body health, including improving antioxidant capacity and maintaining lipid metabolism stability. However, whether dietary GSPE supplementation can improve lipid metabolism in finishing pigs remains unclear. Here 18 castrated male Duroc × Landrace × Yorkshire finishing pigs were randomly divided into three groups with six replicates and one pig per replicate. Pigs were fed a basal diet (control), a basal diet supplemented with 100 mg/kg GSPE, or a basal diet supplemented with 200 mg/kg GSPE for 30 days. Antioxidant analysis showed that dietary 200 mg/kg GSPE supplementation increased glutathione, total antioxidant capacity and glutathione peroxidase levels, and reduced malondialdehyde levels in serum, muscle and liver. Dietary 200 mg/kg GSPE supplementation also upregulated the mRNA and protein levels of nuclear-related factor 2 (Nrf2). Lipid metabolism analysis showed that dietary GSPE supplementation increased serum high-density lipoprotein cholesterol levels and reduced serum triglyceride and total cholesterol levels. Besides, GPSE upregulated the mRNA expression of lipolysis- and fatty acid oxidation-related genes downregulated the mRNA expression of lipogenesis-related genes, and activated the AMPK signal in finishing pigs. Together, we provided evidence that dietary GSPE supplementation improved the antioxidant capacity and lipid metabolism in finishing pigs.


Asunto(s)
Antioxidantes , Extracto de Semillas de Uva , Metabolismo de los Lípidos , Proantocianidinas , Masculino , Animales , Porcinos , Suplementos Dietéticos , Colesterol , ARN Mensajero
9.
Anim Biotechnol ; 34(9): 4900-4909, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37149789

RESUMEN

Intrauterine growth retardation (IUGR) can result in early liver oxidative damage and abnormal lipid metabolism in neonatal piglets. Ferulic acid (FA), a phenolic compound widely found in plants, has many biological functions, such as anti-inflammation and anti-oxidation. Thus, we explored the effects of dietary FA supplementation on antioxidant capacity and lipid metabolism in newborn piglets with IUGR. In the study, 24 7-day-old piglets were divided into three groups: normal birth weight (NBW), IUGR, and IUGR + FA. The NBW and IUGR groups were fed formula milk as a basal diet, while the IUGR + FA group was fed a basal diet supplemented with 100 mg/kg FA. The trial lasted 21 days. The results showed that IUGR decreased absolute liver weight, increased transaminase activity, reduced antioxidant capacity, and disrupted lipid metabolism in piglets. Dietary FA supplementation enhanced absolute liver weight, reduced serum MDA level and ROS concentrations in serum and liver, markedly increased serum and liver GSH-PX and T-SOD activities, decreased serum HDL-C and LDL-C and liver NEFA, and increased TG content and HL activity in the liver. The mRNA expression related to the Nrf2-Keap1 signaling pathway and lipid metabolism in liver were affected by IUGR. Supplementing FA improved the antioxidant capacity of liver by down-regulating Keap1 and up-regulating the mRNA expression of SOD1 and CAT, and regulated lipid metabolism by increasing the mRNA expression level of Fasn, Pparα, LPL, and CD36. In conclusion, the study suggests that FA supplementation can improve antioxidant capacity and alleviate lipid metabolism disorders in IUGR piglets.


Asunto(s)
Antioxidantes , Ácidos Cumáricos , Enfermedades de los Porcinos , Femenino , Animales , Porcinos , Antioxidantes/farmacología , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Metabolismo de los Lípidos , Retardo del Crecimiento Fetal/tratamiento farmacológico , Retardo del Crecimiento Fetal/veterinaria , Retardo del Crecimiento Fetal/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/farmacología , Hígado , Suplementos Dietéticos , ARN Mensajero/metabolismo
10.
Phytother Res ; 37(7): 2759-2770, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36762415

RESUMEN

Eugenol is a major component of clove oil. A recent study found that inhalation of eugenol promoted the appetite of mice. However, whether oral ingestion of eugenol promoted appetite is unclear and its mechanism await study. Here, mice were divided into four treatments (n = 20) and fed a basal diet supplemented with 0%, 0.005%, 0.01% and 0.02% eugenol for 4 weeks. In addition, mice (n = 7) were injected intraperitoneally with 3 mg/kg body weight eugenol. Our data showed that feeding mice with 0.01% and 0.02% eugenol promoted their appetite. In addition, the short-term intraperitoneal injection of eugenol enhanced the feed intake in mice within 1 h. Further studies found that dietary eugenol increased orexigenic factors expression and decreased anorexigenic factors expression in mice. We then carried out N38 cell experiments to explore the transient receptor potential (TRP) channels-dependent mechanism of eugenol in promoting appetite. We found that eugenol activated the TRP channels mediated-CaMKK2/AMPK signaling pathway in the hypothalamus and N38 cells. Besides, the inhibition of TRPV1 and AMPK eliminated the upregulation of eugenol on the agouti-related protein level in N38 cells. In conclusion, the study suggested that eugenol promotes appetite through TRPV1 mediated-CaMKK2/AMPK signaling pathway.


Asunto(s)
Apetito , Canales de Potencial de Receptor Transitorio , Ratones , Animales , Eugenol/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Canales de Potencial de Receptor Transitorio/metabolismo , Transducción de Señal
11.
J Sci Food Agric ; 103(4): 2106-2115, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36460906

RESUMEN

BACKGROUND: This experiment aimed to investigate effects of dietary l-theanine supplementation on pork quality and muscle fiber type transformation in finishing pigs. In a 30-day experiment, 18 healthy Duroc × Landrace × Yorkshire (DLY) pigs with an average body weight of 86.03 ± 0.83 kg were randomly divided into three groups (a basal diet or a basal diet supplemented with 500 and 1000 ppm l-theanine, respectively), with six duplicates and one pig per replicate. RESULTS: The results showed that dietary 1000 ppm l-theanine supplementation significantly reduced (P < 0.05) b*24 h and drip loss. Dietary 1000 ppm l-theanine supplementation significantly increased (P < 0.05) slow myosin heavy chain (MyHC) protein expression and the percentage of slow-twitch fibers, as well as significantly decreased (P < 0.05) fast MyHC protein expression and the percentage of fast-twitch fibers, accompanied by an increase in succinate dehydrogenase (SDH) and malate dehydrogenase (MDH) activities and a decrease in lactate dehydrogenase (LDH) activity. In addition, the adenosine monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway was activated by l-theanine. CONCLUSION: Together, this study demonstrated for the first time that dietary supplementation of 1000 ppm l-theanine can improve pork color and drip loss and promote muscle fiber type transformation from fast-twitch to slow-twitch in finishing pigs. © 2022 Society of Chemical Industry.


Asunto(s)
Carne de Cerdo , Carne Roja , Porcinos , Animales , Fibras Musculares Esqueléticas/metabolismo , Suplementos Dietéticos
12.
Br J Nutr ; 128(8): 1526-1534, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-34763738

RESUMEN

Diarrhoea caused by pathogens such as enterotoxigenic E. coli (ETEC) is a serious threat to the health of young animals and human infants. Here, we investigated the protective effect of fructo-oligosaccharides (FOS) on the intestinal epithelium with ETEC challenge in a weaned piglet model. Twenty-four weaned piglets were randomly divided into three groups: (1) non-ETEC-challenged control (CON); (2) ETEC-challenged control (ECON); and (3) ETEC challenge + 2·5 g/kg FOS (EFOS). On day 19, the CON pigs were orally infused with sterile culture, while the ECON and EFOS pigs were orally infused with active ETEC (2·5 × 109 colony-forming units). On day 21, pigs were slaughtered to collect venous blood and small intestine. Result showed that the pre-treatment of FOS improved the antioxidant capacity and the integrity of intestinal barrier in the ETEC-challenged pigs without affecting their growth performance. Specifically, compared with ECON pigs, the level of GSH peroxidase and catalase in the plasma and intestinal mucosa of EFOS pigs was increased (P < 0·05), and the intestinal barrier marked by zonula occluden-1 and plasmatic diamine oxidase was also improved in EFOS pigs. A lower level (P < 0·05) of inflammatory cytokines in the intestinal mucosa of EFOS pigs might be involved in the inhibition of TLR4/MYD88/NF-κB pathway. The apoptosis of jejunal cells in EFOS pigs was also lower than that in ECON pigs (P < 0·05). Our findings provide convincing evidence of possible prebiotic and protective effect of FOS on the maintenance of intestinal epithelial function under the attack of pathogens.


Asunto(s)
Escherichia coli Enterotoxigénica , Infecciones por Escherichia coli , Enfermedades de los Porcinos , Animales , Humanos , Porcinos , Escherichia coli Enterotoxigénica/fisiología , Mucosa Intestinal/metabolismo , Suplementos Dietéticos , Oligosacáridos/farmacología , Enfermedades de los Porcinos/metabolismo , Destete
13.
Phys Chem Chem Phys ; 24(43): 26836-26847, 2022 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-36317414

RESUMEN

1,1-Diamino-2,2-dinitroethene (FOX-7) is an energetic material with low sensitivity and high detonation performance, thus it has been considered as a potential replacement for traditional nitro-based energetic materials. In a recent publication (J. Phys. Chem. A, 2022, 126, 4747), the initial decomposition steps of FOX-7 were studied using reflectron time-of-flight mass spectrometry and infrared spectroscopy. The experimental study was complemented with quantum chemistry calculations, which demonstrated the gas phase potential energy surface to be indicative of the reaction process in the condensed phase. The computation in J. Phys. Chem. A, 2022, 126, 4747 focuses on the primary decomposition - but in this manuscript, the full decomposition pathway on the singlet surface, consisting of 54 intermediates and 37 transition states, is characterized at an unprecedented detail. The calculations show that the nitro group, instead of the amine group, is primarily responsible for the sensitivity and endothermicity of FOX-7 decomposition. This result sheds light on how to critically optimize the performance of FOX-7 and design the next generation of nitro-based energetic materials. A comprehensive roadmap, initiated from FOX-7, covers the chemical space of the entire decomposition thus providing a holistic demonstration of various key decomposition pathways leading to various small, gas phase products such as NO, NO2, NH2, CO2, and CO.

14.
Phys Chem Chem Phys ; 24(33): 19761-19772, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35971984

RESUMEN

Silicon monoxide (SiO) is classified as a key precursor and fundamental molecular building block to interstellar silicate nanoparticles, which play an essential role in the synthesis of molecular building blocks connected to the Origins of Life. In the cold interstellar medium, silicon monoxide is of critical importance in initiating a series of elementary chemical reactions leading to larger silicon oxides and eventually to silicates. To date, the fundamental formation mechanisms and chemical dynamics leading to gas phase silicon monoxide have remained largely elusive. Here, through a concerted effort between crossed molecular beam experiments and electronic structure calculations, it is revealed that instead of forming highly-stable silicon dioxide (SiO2), silicon monoxide can be formed via a barrierless, exoergic, single-collision event between ground state molecular oxygen and atomic silicon involving non-adiabatic reaction dynamics through various intersystem crossings. Our research affords persuasive evidence for a likely source of highly rovibrationally excited silicon monoxide in cold molecular clouds thus initiating the complex chain of exoergic reactions leading ultimately to a population of silicates at low temperatures in our Galaxy.

15.
J Phys Chem A ; 2022 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-35852300

RESUMEN

The UV photolysis of solid FOX-7 at 5 K with 355 and 532 nm photons was investigated to unravel initial isomerization and decomposition pathways. Isomer-selective single photon ionization coupled with reflectron time-of-flight mass spectrometry (ReTOF-MS) documented the nitric oxide (NO) loss channel at 355 nm along with a nitro-to-nitrite isomerization, which was observed by using infrared spectroscopy, representing the initial reaction pathway followed by O─NO bond rupture of the nitrite moiety. A residual gas analyzer detected molecular oxygen for the 355 and 532 nm photolysis at a ratio of 4.3 ± 0.3:1, which signifies FOX-7 as an energetic material that provides its own oxidant once the decomposition starts. Overall branching ratios for molecular oxygen versus nitric oxide were derived to be 700 ± 100:1 at 355 nm. It is notable that this is the first time that molecular oxygen was detected as a decomposition product of FOX-7. Computations show that atomic oxygen, which later combines to form molecular oxygen, is likely released from a nitro group involving conical intersections. The condensed phase potential energy profile computed at the CCSD(T) and CASPT2 level correlates well with the experiments and highlights the critical roles of conical intersections, nonadiabatic dynamics, and the encapsulated environment that dictate the mechanism of the reaction through intermolecular hydrogen bonds.

16.
J Nat Prod ; 85(2): 415-425, 2022 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-35142496

RESUMEN

As part of a study examining polar metabolites produced by cyanobacterial strains, we examined media extracts of a Calothrix sp. (strain R-3-1) and a Scytonema sp. (strain U-3-3). The cell mass of each was separated from the media, and HP20 resin was added for adsorption of secreted metabolites, a relatively unexplored area of cyanobacterial chemistry. HPLC-UV-LCMS-guided isolation led to the discovery of seven sesquiterpenoid compounds with five new, one known, and one previously isolated as the methyl ester. Through a complement of 1D and 2D NMR spectroscopic techniques, the planar structures and relative configurations of the seven compounds were elucidated. Spironostoic acid (1), 11,12-didehydrospironostoic acid (2), and 12-hydroxy-2-oxo-11-epi-hinesol (4) are spirovetivane-type compounds from R-3-1, while stigolone (5), 11R,12-dihydroxystigolone (6), and 11S,12-dihydroxystigolone (7) are three eudesmane-type compounds from U-3-3. Circular dichroism was utilized to decipher the absolute configurations of new compounds 1, 2, 4, 5, 6, and 7. Due to the structural variety observed among the spirovetivane- and eudesmane-type compounds in the literature and often a lack of clarity in how determinations were made, computational spectra and model compounds were used to support the interpretation of ECD and NMR spectra. A straightforward process to determine the configuration of these systems is presented.


Asunto(s)
Sesquiterpenos de Eudesmano , Sesquiterpenos , Medios de Cultivo , Estructura Molecular , Sesquiterpenos/química , Sesquiterpenos de Eudesmano/química
17.
BMC Vet Res ; 18(1): 142, 2022 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-35440001

RESUMEN

BACKGROUND: Antimicrobial peptides including various defensins have been attracting considerable research interest worldwide, as they have potential to substitute for antibiotics. Moreover, AMPs also have immunomodulatory activity. In this study, we explored the role and its potential mechanisms of ß-defensin 118 (DEFB118) in alleviating inflammation and injury of IPEC-J2 cells (porcine jejunum epithelial cell line) upon the enterotoxigenic Escherichia coli (ETEC) challenge. RESULTS: The porcine jejunum epithelial cell line (IPEC-J2) pretreated with or without DEFB118 (25 µg/mL) were challenged by ETEC (1×106 CFU) or culture medium. We showed that DEFB118 pretreatment significantly increased the cell viability (P<0.05) and decreased the expressions of inflammatory cytokines such as the interleukin-1ß (IL-1ß), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in IPEC-J2 cells exposure to ETEC (P<0.05). Interestingly, DEFB118 pretreatment significantly elevated the abundance of the major tight-junction protein zonula occludens-1 (ZO-1), but decreased the number of apoptotic cells upon ETEC challenge (P<0.05). The expression of caspase 3, caspase 8, and caspase 9 were downregulated by DEFB118 in the IPEC-J2 cells exposure to ETEC (P<0.05). Importantly, DEFB118 suppressed two critical inflammation-associated signaling proteins, nuclear factor-kappa-B inhibitor alpha (IκB-α) and nuclear factor-kappaB (NF-κB) in the ETEC-challenged IPEC-J2 cells. CONCLUSIONS: DEFB118 can alleviate ETEC-induced inflammation in IPEC-J2 cells through inhibition of the NF-κB signaling pathway, resulting in reduced secretion of inflammatory cytokines and decreased cell apoptosis. Therefore, DEFB118 can act as a novel anti-inflammatory agent.


Asunto(s)
Escherichia coli Enterotoxigénica , Infecciones por Escherichia coli , Inflamación , Enfermedades de los Porcinos , beta-Defensinas , Animales , Citocinas/metabolismo , Escherichia coli Enterotoxigénica/fisiología , Células Epiteliales/metabolismo , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/veterinaria , Inflamación/metabolismo , Inflamación/veterinaria , Mucosa Intestinal/metabolismo , FN-kappa B/metabolismo , Porcinos , Enfermedades de los Porcinos/patología , beta-Defensinas/metabolismo
18.
Anim Biotechnol ; 33(3): 563-570, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34866548

RESUMEN

In this study, eighteen healthy Duroc × Landrace × Yorkshire barrows with initial body weight of 63.89 ± 1.15 kg were randomly allotted to three treatments and fed a basal diet or a basal diet supplemented with 100 mg/kg and 200 mg/kg lycopene, respectively. Data showed that villus height to crypt depth ratio increased with 200 mg/kg lycopene (p < 0.05) in the jejunum. In duodenum, the malondialdehyde content was decreased (p < 0.05) in 100 and 200 mg/kg lycopene groups. Furthermore, in the jejunum, dietary 100 and 200 mg/kg lycopene supplementation increased (p < 0.05) catalase activity. In the duodenum, interleukin-1ß (IL-1ß), nuclear factor-κB and tumor necrosis factor-α contents were decreased (p < 0.05) in 200 mg/kg lycopene group. In the jejunum, IL-1ß content was reduced (p < 0.05) and IL-1ß mRNA expression was down-regulated (p = 0.046) in 200 mg/kg lycopene group. Additionally, claudin-1 mRNA and protein levels in 200 mg/kg group were also increased (p < 0.05). These results indicated that dietary lycopene supplementation could maintain intestinal health, which was associated with improving intestinal morphology, enhancing tight junction function, inhibiting inflammatory response, and elevating antioxidant capacity in finishing pigs.


Asunto(s)
Antioxidantes , Suplementos Dietéticos , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Dieta/veterinaria , Licopeno/farmacología , ARN Mensajero/genética , Porcinos
19.
Anim Biotechnol ; 33(3): 555-562, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34866549

RESUMEN

This study aimed to investigate the effect of dietary dihydromyricetin (DHM) supplementation on lipid metabolism, antioxidant capacity and muscle fiber type transformation. Twenty-four male Kunming mice were randomly allotted to either control (basal diet) or DHM diets (supplemented with 300 mg/kg DHM). Our data showed that DHM administration decreased the triglycerides (TG) and low-density lipoprotein cholesterol (LDL-C) contents, and increased the catalase (CAT), total superoxide dismutase (T-SOD) and glutathione peroxidase (GSH-Px) activities in serum. In the liver, DHM decreased the TG and malondialdehyde (MDA) levels and increased the T-SOD and GSH-Px activities. For the tibialis anterior (TA) muscle, DHM increased the total antioxidant capacity (T-AOC) level and T-SOD activities. Western blotting and real-time quantitative PCR analysis showed that DHM increased the protein and mRNA levels of MyHC I and MyHC IIa and decreased the protein and mRNA levels of MyHC IIb in TA muscle, which may be achieved by activating the AMP-activated protein kinase (AMPK) signal. The mRNA levels of several regulatory factors related to mitochondrial function were up-regulated by DHM. In conclusion, dietary 300 mg/kg DHM supplementation improved lipid metabolism and antioxidant capacity and promoted the transformation of muscle fiber type from glycolysis to oxidation in mice.


Asunto(s)
Antioxidantes , Metabolismo de los Lípidos , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Suplementos Dietéticos , Flavonoles , Masculino , Ratones , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , ARN Mensajero/metabolismo , Superóxido Dismutasa
20.
Anim Biotechnol ; 33(7): 1398-1406, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35838495

RESUMEN

In this study, we investigated the effect of dietary dihydromyricetin (DHM) supplementation on intestinal barrier and humoral immunity in growing-finishing pigs. The data showed that dietary DHM supplementation improved jejunal barrier function by upregulating the protein expressions of Occludin and Claudin-1 and the mRNA levels of MUC1 and MUC2. Dietary DHM supplementation increased the amylase, lipase, sucrase and maltase activities and the mRNA expression of nutrient transporter (SGLT1, GLUT2, PepT1) in the jejunum mucosa. Dietary DHM supplementation significantly reduced the E. coli population in the cecum and colon and increased the Lactobacillus population in the cecum. In addition, dietary DHM supplementation increased the contents of butyric acid and valeric acid in cecum and colon. In serum, dietary DHM supplementation reduced interleukin-1ß (IL-1ß) content and increased interleukin-10 (IL-10), Immunoglobulin M (IgM) and Immunoglobulin A (IgA) contents (p < 0.05). In addition, compared with the control group, dietary DHM supplementation improved secretory immunoglobulin A (sIgA) and interleukin-10 (IL-10) contents and down-regulated TNF-α protein expression in jejunum mucosa (p < 0.05). Together, this study demonstrated that dietary DHM supplementation improved intestinal barrier function, digestion and absorption capacity and immune function in growing-finishing pigs.


Asunto(s)
Suplementos Dietéticos , Flavonoles , Inmunidad Humoral , Intestinos , Animales , Alimentación Animal/análisis , Dieta/veterinaria , Interleucina-10 , ARN Mensajero/metabolismo , Porcinos , Intestinos/microbiología , Flavonoles/farmacología
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