Initial decomposition pathways of 1,1-diamino-2,2-dinitroethylene (α-FOX-7) in the condensed phase.

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.

The initial sticking of high velocity water onto graphite under non-equilibrium supersonic flow conditions.

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.

Prebiotic inulin as a treatment of obesity related nonalcoholic fatty liver disease through gut microbiota: a critical review.

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.

Electron-Induced Decomposition of Solid 1,1-Diamino-2,2-dinitroethylene (FOX-7) at Cryogenic Temperatures.

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.

Anti-inflammatory Quinoline Alkaloids from the Roots of Waltheria indica.

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.

A chemical dynamics study on the gas phase formation of thioformaldehyde (H2CS) and its thiohydroxycarbene isomer (HCSH).

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.

A chemical dynamics study on the gas-phase formation of triplet and singlet C5H2 carbenes.

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.

Dietary grape seed proanthocyanidin extract supplementation improves antioxidant capacity and lipid metabolism in finishing pigs.

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.

Dietary ferulic acid supplementation improves antioxidant capacity and lipid metabolism in liver of piglets with intrauterine growth retardation.

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.

Eugenol promotes appetite through TRP channels mediated-CaMKK2/AMPK signaling pathway.

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.

Effects of dietary l-theanine supplementation on pork quality and muscle fiber type transformation in finishing pigs.

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.

Dietary supplementation of fructo-oligosaccharides alleviates enterotoxigenic E. coli-induced disruption of intestinal epithelium in a weaned piglet model.

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.

The potential energy profile of the decomposition of 1,1-diamino-2,2-dinitroethylene (FOX-7) in the gas phase.

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.

Gas-phase formation of silicon monoxide via non-adiabatic reaction dynamics and its role as a building block of interstellar silicates.

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.

Exploring the Photochemistry of Solid 1,1-Diamino-2,2-dinitroethylene (FOX-7) Spanning Simple Bond Ruptures, Nitro-to-Nitrite Isomerization, and Nonadiabatic Dynamics.

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.

Spirovetivane- and Eudesmane-Type Sesquiterpenoids Isolated from the Culture Media of Two Cyanobacterial Strains.

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.

ß-defensin 118 attenuates inflammation and injury of intestinal epithelial cells upon enterotoxigenic Escherichia coli challenge.

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.

Resveratrol regulates muscle fiber type gene expression through AMPK signaling pathway and miR-22-3p in porcine myotubes.

This study aimed to investigate the effect and underlying mechanisms of resveratrol on porcine muscle fiber type gene expression in porcine myotubes. Here, results showed that resveratrol treatment significantly promoted slow myosin heavy chain (MyHC) and inhibited fast MyHC in porcine myotubes. The phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) and the downstream factors of AMPK signaling, such as Sirtuin1 (Sirt1) and peroxlsome proliferator-activated receptor-γ coactlvator-1α (PGC-1α), were also increased by resveratrol, suggesting that resveratrol could activate the AMPK signaling pathway. Interestingly, resveratrol inhibited the expression of miR-22-3p in porcine myotubes. Furthermore, AMPK inhibitor compound C and miR-22-3p mimic effectively eliminated the effects of resveratrol on slow MyHC and fast MyHC expressions in porcine myotubes. Taken together, our findings indicate that resveratrol regulates muscle fiber type gene expression through the AMPK signaling pathway and miR-22-3p in porcine myotubes.

Procyanidin B2 induces porcine skeletal slow-twitch myofiber gene expression by AMP-activated protein kinase signaling pathway.

In this study, our aim is to investigate the effect of dimer procyanidin B2 [epicatechin-(4ß-8)-epicatechin] (PB2) on porcine skeletal myofiber gene expression in vitro. Our data showed PB2 promoted the protein expression of slow myosin heavy chain (MyHC) in porcine myotubes, concomitant with the increases in mRNA levels of MyHC I, MyHC IIa and Tnni1. We also found PB2 activated AMPK signaling in porcine myotubes. NRF1 and CaMKKß that are two important upstream factors of AMPK, and Sirt1 and PGC-1α that are two major downstream factors of AMPK, were also up-regulated by PB2. The mechanism study showed the effect of PB2 on slow-twitch myofiber gene expression was abolished by AMPK inhibitor compound C or by AMPKα1 siRNA. Together, we found PB2 induced porcine skeletal slow-twitch myofiber gene expression by AMPK signaling pathway.

Effects of dietary lycopene supplementation on intestinal morphology, antioxidant capability and inflammatory response in finishing pigs.

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.