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All cells are subject to geometric constraints, such as surface area-to-volume (SA/V) ratio, that impact cell functions and force biological adaptations. Like the SA/V ratio of a sphere, it is generally assumed that the SA/V ratio of cells decreases as cell size increases. Here, we investigate this in near-spherical mammalian cells using single-cell measurements of cell mass and surface proteins, as well as imaging of plasma membrane morphology. We find that the SA/V ratio remains surprisingly constant as cells grow larger. This observation is largely independent of the cell cycle and the amount of cell growth. Consequently, cell growth results in increased plasma membrane folding, which simplifies cellular design by ensuring sufficient membrane area for cell division, nutrient uptake and deformation at all cell sizes.
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Eukaryotic phytoplankton, also known as algae, form the basis of marine food webs and drive marine carbon sequestration. Algae must regulate their motility and gravitational sinking to balance access to light at the surface and nutrients in deeper layers. However, the regulation of gravitational sinking remains largely unknown, especially in motile species. Here, we quantify gravitational sinking velocities according to Stokes' law in diverse clades of unicellular marine microalgae to reveal the cell size, density, and nutrient dependency of sinking velocities. We identify a motile algal species, Tetraselmis sp., that sinks faster when starved due to a photosynthesis-driven accumulation of carbohydrates and a loss of intracellular water, both of which increase cell density. Moreover, the regulation of cell sinking velocities is connected to proliferation and can respond to multiple nutrients. Overall, our work elucidates how cell size and density respond to environmental conditions to drive the vertical migration of motile algae.
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Tamaño de la Célula , Nutrientes , Nutrientes/metabolismo , Gravitación , Fitoplancton/fisiología , Fitoplancton/metabolismo , Fotosíntesis , Microalgas/metabolismoRESUMEN
The natural van der Waals superlattice MnBi2Te4-(Bi2Te3)m provides an optimal platform to combine topology and magnetism in one system with minimal structural disorder. Here, we show that this system can harbor both ferromagnetic (FM) and antiferromagnetic (AFM) orders and that these magnetic orders can be controlled in two different ways by either varying the Mn-Mn distance while keeping the Bi2Te3/MnBi2Te4 ratio constant or vice versa. We achieve this by creating atomically engineered sandwich structures composed of Bi2Te3 and MnBi2Te4 layers. We show that the AFM order is exclusively determined by the Mn-Mn distance, whereas the FM order depends only on the overall Bi2Te3/MnBi2Te4 ratio regardless of the distance between the MnBi2Te4 layers. Our results shed light on the origins of the AFM and FM orders and provide insights into how to manipulate magnetic orders not only for the MnBi2Te4-Bi2Te3 system but also for other magneto-topological materials.
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Cell density, the ratio of cell mass to volume, is an indicator of molecular crowding and therefore a fundamental determinant of cell state and function. However, existing density measurements lack the precision or throughput to quantify subtle differences in cell states, particularly in primary samples. Here we present an approach for measuring the density of 30,000 single cells per hour with a precision of 0.03% (0.0003 g/mL) by integrating fluorescence exclusion microscopy with a suspended microchannel resonator. Applying this approach to human lymphocytes, we discovered that cell density and its variation decrease as cells transition from quiescence to a proliferative state, suggesting that the level of molecular crowding decreases and becomes more regulated upon entry into the cell cycle. Using a pancreatic cancer patient-derived xenograft model, we found that the ex vivo density response of primary tumor cells to drug treatment can predict in vivo tumor growth response. Our method reveals unexpected behavior in molecular crowding during cell state transitions and suggests density as a new biomarker for functional precision medicine.
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Rare-earth monopnictides are a family of materials simultaneously displaying complex magnetism, strong electronic correlation, and topological band structure. The recently discovered emergent arc-like surface states in these materials have been attributed to the multi-wave-vector antiferromagnetic order, yet the direct experimental evidence has been elusive. Here we report observation of non-collinear antiferromagnetic order with multiple modulations using spin-polarized scanning tunneling microscopy. Moreover, we discover a hidden spin-rotation transition of single-to-multiple modulations 2 K below the Néel temperature. The hidden transition coincides with the onset of the surface states splitting observed by our angle-resolved photoemission spectroscopy measurements. Single modulation gives rise to a band inversion with induced topological surface states in a local momentum region while the full Brillouin zone carries trivial topological indices, and multiple modulation further splits the surface bands via non-collinear spin tilting, as revealed by our calculations. The direct evidence of the non-collinear spin order in NdSb not only clarifies the mechanism of the emergent topological surface states, but also opens up a new paradigm of control and manipulation of band topology with magnetism.
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BACKGROUND: Gastric remnant bleeding is a special case of upper gastrointestinal bleeding with certain specific disease characteristics, and some matters of transcatheter arterial embolization (TAE) for hemostasis need attention. In this study, we aimed to explore the clinical use of TAE in patients with nonvariceal gastric remnant bleeding and identify the factors influencing the clinical efficacy of these interventions. METHODS: Data were retrospectively analyzed from 42 patients for whom angiography and embolization were performed but could not be treated endoscopically or had failed endoscopic management in our department between January 2018 and January 2023 due to nonvariceal gastric remnant bleeding. We investigated the relationship between the incidence of re-bleeding and the following variables: sex, age, pre-embolization gastroscopy/contrast-enhanced computer tomography, embolization method, aortography performance, use of endoscopic titanium clips, and the presence of collateral gastric-supplying arteries. RESULTS: Forty-two patients underwent 47 interventional embolizations. Of these, 16 were positive for angiographic findings, and 26 were negative. Based on arteriography results, different embolic agents were selected, and the technical success rate was 100%. The incidence of postoperative re-bleeding was 19.1% (9/47), and the overall clinical success rate was 81.0% (34/42). Logistic regression analysis of the relationship between the incidence of early re-bleeding following embolization and the proportion of collateral gastric supply arteries revealed an odds ratio of 10.000 (p = 0.014). CONCLUSIONS: Utilizing TAE for nonvariceal gastric remnant bleeding is safe and effective. The omission of collateral gastric-supplying arteries can lead to early re-bleeding following an intervention.
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Embolización Terapéutica , Muñón Gástrico , Humanos , Estudios Retrospectivos , Hemorragia Gastrointestinal/etiología , Hemorragia Gastrointestinal/terapia , Embolización Terapéutica/efectos adversos , GastroscopíaRESUMEN
The interface between two different materials can show unexpected quantum phenomena. In this study, we used molecular beam epitaxy to synthesize heterostructures formed by stacking together two magnetic materials, a ferromagnetic topological insulator (TI) and an antiferromagnetic iron chalcogenide (FeTe). We observed emergent interface-induced superconductivity in these heterostructures and demonstrated the co-occurrence of superconductivity, ferromagnetism, and topological band structure in the magnetic TI layer-the three essential ingredients of chiral topological superconductivity (TSC). The unusual coexistence of ferromagnetism and superconductivity is accompanied by a high upper critical magnetic field that exceeds the Pauli paramagnetic limit for conventional superconductors at low temperatures. These magnetic TI/FeTe heterostructures with robust superconductivity and atomically sharp interfaces provide an ideal wafer-scale platform for the exploration of chiral TSC and Majorana physics.
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Background: Transcatheter bladder arterial chemoembolization (TACE) is an alternative treatment used to control bladder cancer (BC) with bleeding, especially in older adult patients with comorbidities. This retrospective observational study evaluated the effect and prognostic factors of transcatheter drug-eluting bead (DEB) embolization in patients with advanced BC. Methods: We assessed 39 patients diagnosed with BC with hemorrhage who were either inoperable or unwilling to undergo surgery at our hospital between January 2018 and October 2022. All patients underwent TACE by DEB loaded with epirubicin and imaging scans after 2 months to evaluate the curative effect according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST) standard to determine treatment. Re-examination and follow-up were performed every 3-6 months to observe hematuria recurrence and the curative effect. Results: A total of 95 interventional treatments were performed in 39 patients, and all participants achieved complete hemostasis within 5 days after the first intervention. Computed tomography or magnetic resonance imaging showed that the total effective rate [complete response (CR) + partial response (PR)] was 64.1%, and the disease benefit rate (CR +PR + stable disease) was 79.5%. A total of 30 patients (76.9%) had no hematuria recurrence. Logistic regression analysis indicated that the type of blood supply in BC may relate to whether the patients benefited from the intervention. Hematuria recurrence was significantly associated with the total number of tumors and the type of blood supply (P<0.05). Conclusions: Superselective embolization of bladder arteries with DEB can be used to treat BC with hemorrhage. However, hypovascular tumor blood supply may result in poor postoperative efficacy and hematuria recurrence. Additionally, multiple bladder tumors may be a risk factor for hematuria recurrence.
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Control and understanding of ensembles of skyrmions is important for realization of future technologies. In particular, the order-disorder transition associated with the 2D lattice of magnetic skyrmions can have significant implications for transport and other dynamic functionalities. To date, skyrmion ensembles have been primarily studied in bulk crystals, or as isolated skyrmions in thin film devices. Here, we investigate the condensation of the skyrmion phase at room temperature and zero field in a polar, van der Waals magnet. We demonstrate that we can engineer an ordered skyrmion crystal through structural confinement on the µm scale, showing control over this order-disorder transition on scales relevant for device applications.
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Ingeniería , Imanes , Temperatura , Fenómenos Físicos , Fenómenos MagnéticosRESUMEN
BACKGROUND: Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator, promoting intestinal development and regulating intestinal flora in the gut. However, the relevant mechanisms remain obscure. In this study, pigs were fed a corn-soybean meal-based diet supplemented with either 5% microcrystalline cellulose (MCC) or 5% pectin for 3 weeks, to investigate the metabolites and anti-inflammatory properties of the jejunum. RESULT: The results showed that dietary pectin supplementation improved intestinal integrity (Claudin-1, Occludin) and inflammatory response [interleukin (IL)-10], and the expression of proinflammatory cytokines (IL-1ß, IL-6, IL-8, TNF-α) was down-regulated in the jejunum. Moreover, pectin supplementation altered the jejunal microbiome and tryptophan-related metabolites in piglets. Pectin specifically increased the abundance of Lactococcus, Enterococcus, and the microbiota-derived metabolites (skatole (ST), 3-indoleacetic acid (IAA), 3-indolepropionic acid (IPA), 5-hydroxyindole-3-acetic acid (HIAA), and tryptamine (Tpm)), which activated the aryl hydrocarbon receptor (AhR) pathway. AhR activation modulates IL-22 and its downstream pathways. Correlation analysis revealed the potential relationship between metabolites and intestinal morphology, intestinal gene expression, and cytokine levels. CONCLUSION: In conclusion, these results indicated that pectin inhibits the inflammatory response by enhancing the AhR-IL22-signal transducer and activator of transcription 3 signaling pathway, which is activated through tryptophan metabolites.
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As pectin is widely used as a food and feed additive due to its tremendous prebiotic potentials for gut health. Yet, the underlying mechanisms associated with its protective effect remain unclear. Twenty-four piglets (Yorkshire × Landrace, 6.77 ± 0.92 kg) were randomly divided into three groups with eight replicates per treatment: (1) Control group (CON), (2) Lipopolysaccharide-challenged group (LPS), (3) Pectin-LPS group (PECL). Piglets were administrated with LPS or saline on d14 and 21 of the experiment. Piglets in each group were fed with corn-soybean meal diets containing 5% citrus pectin or 5% microcrystalline cellulose. Our result showed that pectin alleviated the morphological damage features by restoring the goblet numbers which the pig induced by LPS in the cecum. Besides, compared with the LPS group, pectin supplementation elevated the mRNA expression of tight junction protein [Claudin-1, Claudin-4, and zonula occludens-1 (ZO-1)], mucin (Muc-2), and anti-inflammatory cytokines [interleukin 10 (IL-10), and IL-22]. Whereas pectin downregulated the expression of proinflammatory cytokines (IL-1ß, IL-6, IL-18), tumor necrosis factor-&alpha (TNF-α), and NF-κB. What is more, pectin supplementation also significantly increased the abundance of beneficial bacteria (Lactobacillus, Clostridium_sensu_stricto_1, Blautia, and Subdoligranulum), and significantly reduced the abundance of harmful bacteria, such as Streptococcus. Additionally, pectin restored the amount of short-chain fatty acids (SCFAs) after being decreased by LPS (mainly Acetic acid, Propionic acid, and Butyric acid) to alleviate gut injury and improve gut immunity via activating relative receptors (GPR43, GPR109, AhR). Mantel test and correlation analysis also revealed associations between intestinal microbiota and intestinal morphology, and intestinal inflammation in piglets. Taken together, dietary pectin supplementation enhances the gut barrier and improves immunity to ameliorate LPS-induced injury by optimizing gut microbiota and their metabolites.
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We report direct visualization of spin-flip transition of the surface layer in antiferromagnet MnBi_{4}Te_{7}, a natural superlattice of alternating MnBi_{2}Te_{4} and Bi_{2}Te_{3} layers, using cryogenic magnetic force microscopy (MFM). The observation of magnetic contrast across domain walls and step edges confirms that the antiferromagnetic order persists to the surface layers. The magnetic field dependence of the MFM images reveals that the surface magnetic layer undergoes a first-order spin-flip transition at a magnetic field that is lower than the bulk transition, in excellent agreement with a revised Mills model. Our analysis suggests no reduction of the order parameter in the surface magnetic layer, implying robust ferromagnetism in the single-layer limit. The direct visualization of surface spin-flip transition not only opens up exploration of surface metamagnetic transitions in layered antiferromagnets, but also provides experimental support for realizing quantized transport in ultrathin films of MnBi_{4}Te_{7} and other natural superlattice topological magnets.
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BACKGROUND: Post-weaning diarrhea in piglets reduces growth performance and increases mortality, thereby causing serious economic losses. The intestinal epithelial cells and microbiota reciprocally regulate each other in order to maintain intestinal homeostasis and control inflammation. However, a relative paucity of research has been focused on the host-derived regulatory network that controls mucin O-glycans and thereby changes gut microbiota during diarrhea in infancy. At the development stage just after birth, the ontogeny of intestinal epithelium, immune system, and gut microbiota appear similar in piglets and human infants. Here, we investigated the changes of mucin O-glycans associated with gut microbiota using a diarrheal post-weaned piglet model. RESULTS: We found that diarrhea disrupted the colonic mucus layer and caused aberrant mucin O-glycans, including reduced acidic glycans and truncated glycans, leading to an impaired gut microenvironment. Subsequently, the onset of diarrhea, changes in microbiota and bacterial translocation, resulting in compromised epithelial barrier integrity, enhanced susceptibility to inflammation, and mild growth faltering. Furthermore, we found the activation of NLRP3 inflammasome complexes in the diarrheal piglets when compared to the healthy counterparts, triggered the release of proinflammatory cytokines IL-1ß and IL-18, and diminished autophagosome formation, specifically the defective conversion of LC3A/B I into LC3A/B II and the accumulation of p62. Additionally, selective blocking of the autophagy pathway by 3-MA led to the reduction in goblet cell-specific gene transcript levels in vitro. CONCLUSIONS: We observed that diarrheal piglets exhibited colonic microbiota dysbiosis and mucosal barrier dysfunction. Our data demonstrated that diarrhea resulted in the activation of inflammasomes and autophagy restriction along with aberrant mucin O-glycans including reduced acidic glycans and truncated glycans. The results suggested the mucin O-glycans-microbiota axis is likely associated with diarrheal pathogenesis. Our study provides novel insights into the pathophysiology of early-weaning-induced diarrheal disease in piglets and potentially understanding of disease mechanisms of diarrhea for human infants. Understanding the molecular pathology and pathogenesis of diarrhea is a prerequisite for the development of novel and effective therapies. Our data suggest that facilitating O-glycan elongation, modifying the microbiota, and developing specific inhibitors to some key inflammasomes could be the options for therapy of diarrhea including human infants. Video abstract.
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Diarrea , Microbioma Gastrointestinal , Mucinas , Polisacáridos , Animales , Diarrea/microbiología , Modelos Animales de Enfermedad , Microbioma Gastrointestinal/fisiología , Homeostasis , Humanos , Inflamasomas , Inflamación , Mucinas/metabolismo , Polisacáridos/metabolismo , PorcinosRESUMEN
During weaning, infants and young animals are susceptible to severe enteric infections, thus inducing intestinal microbiota dysbiosis, intestinal inflammation, and impaired intestinal barrier function. Pectin (PEC), a prebiotic polysaccharide, enhances intestinal health with the potential for a therapeutic effect on intestinal diseases. One 21-d study was conducted to investigate the protective effect of pectin against intestinal injury induced by intraperitoneal injection of Escherichia coli lipopolysaccharide (LPS) in a piglet model. A total of 24 piglets (6.77±0.92 kg BW; Duroc × Landrace × Large White; barrows; 21 d of age) were randomly assigned into three groups: control group, LPS-challenged group, and PEC + LPS group. Piglets were administrated with LPS or saline on d14 and d21 of the experiment. All piglets were slaughtered and intestinal samples were collected after 3 h administration on d21. Pectin supplementation ameliorated the LPS-induced inflammation response and damage to the ileal morphology. Meanwhile, pectin also improved intestinal mucin barrier function, increased the mRNA expression of MUC2, and improved intestinal mucus glycosylation. LPS challenge reduced the diversity of intestinal microbiota and enriched the relative abundance of Helicobacter. Pectin restored alpha diversity and improved the structure of the gut microbiota by enriching anti-inflammatory bacteria and short-chain fatty acids (SCFAs)-producing bacteria, and increased the concentrations of acetate. In addition, Spearman rank correlation analysis also revealed the potential relationship between intestinal microbiota and intestinal morphology, intestinal inflammation, and intestinal glycosylation in piglets. Taken together, these results indicate that pectin enhances intestinal integrity and barrier function by altering intestinal microbiota composition and their metabolites, which subsequently alleviates intestinal injury and finally improves the growth performance of piglets.
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Microbioma Gastrointestinal , Lipopolisacáridos , Animales , Suplementos Dietéticos , Ácidos Grasos Volátiles , Inflamación/metabolismo , Lipopolisacáridos/toxicidad , Mucinas , Pectinas/farmacología , ARN Mensajero , PorcinosRESUMEN
Purpose: Microwave ablation has become an alternative treatment for pulmonary ground-glass nodules (GGN) and is widely accepted by clinicians. However, its effect on lung function remains unknown. Therefore, this retrospective study aimed to explore pulmonary function changes and associated risk factors in patients undergoing computed tomography (CT)-guided microwave ablation (MWA) for treating pulmonary GGN. Materials and Methods: Thirty-five patients diagnosed with pulmonary GGN on thin-layer chest CT and enhanced CT were examined. Patients unable or unwilling to undergo thoracoscopic surgery underwent CT-guided simultaneous percutaneous core needle biopsy and MWA. Pulmonary function tests (PFT) were performed before ablation and 3 days and 6 months post-ablation. Forced expiratory volume in one second (FEV1), FEV1%, forced vital capacity (FVC), maximal voluntary ventilation (MVV), and peak expiratory flow (PEF) values pre- and post-MWA were analysed. Linear regression analysis was used to examine the correlation between ablation volume and changes in PFT findings 3 days post-ablation. Associations between patient characteristics, rates of postoperative complications, and PFT findings were analysed. Results: Forty-eight lesions were completely ablated and examined intraoperatively. There were significant differences in pre- and post-operative PFT findings on day 3 but not at 6 months. The mean ablation volume after 3 days of 11.4 ± 6.3 cm3 was positively correlated with changes in FEV1, MVV, and PEF values. Patients' age (mean, 59.4 ± 13.0 years) positively correlated with changes in PEF values. The rates of change in FVC and MVV values were significantly higher with multiple pulmonary nodules than with isolated pulmonary nodule. PFT findings were similar between patients who experienced or did not experience complications (eg, pneumothorax and pleural effusion). Conclusions: Pulmonary function could be impaired shortly after MWA. PFT findings may correlate with age, ablation volume, and number of ablated lesions. In most patients, pulmonary function returned to the preoperative state after 6 months.
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Nódulos Pulmonares Múltiples , Anciano , Humanos , Pulmón/diagnóstico por imagen , Pulmón/cirugía , Microondas/uso terapéutico , Persona de Mediana Edad , Estudios Retrospectivos , Tomografía Computarizada por Rayos XRESUMEN
Early weaning stress (EWS) in piglets is associated with intestinal dysfunction. Here, utilizing a pig EWS model to mimic early-life stress (ELS) in humans, we investigated the mechanism of ELS-induced intestinal diseases through integrated multi-omics analyses of proteome, glycome, and microbiome. Our results demonstrated that EWS resulted in disrupted the ileal barrier integrity by reducing tight junction-related gene expression and interfering with cell-cell adhesion paralleled the increased proportion of pathogens such as Escherichia_Shigella and Helicobacter. Furthermore, Proteome data revealed that the accumulation of unfolded proteins and insufficient unfolded protein response (UPR) process caused by EWS led to ER stress. Data from proteome and glycome found that EWS induced aberrant mucin O-glycans, including truncated glycans, reduction in acidic glycans, and increased in fucosylated glycans. In addition, correlation test by taking fucose and inflammatory response into account suggested that enhancement of fucose expression might be a compensatory host response. Taken together, these results extend the comprehensive knowledge of the detrimental impacts and pathogenesis of EWS and help to provide intervention targets for ELS-induced intestinal diseases in the future.
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Fucosa , Mucinas , Animales , Fucosa/metabolismo , Mucosa Intestinal/metabolismo , Mucinas/metabolismo , Polisacáridos/metabolismo , Proteoma/metabolismo , PorcinosRESUMEN
Novel magnetic ground states have been stabilized in two-dimensional (2D) magnets such as skyrmions, with the potential next-generation information technology. Here, we report the experimental observation of a Néel-type skyrmion lattice at room temperature in a single-phase, layered 2D magnet, specifically a 50% Co-doped Fe5GeTe2 (FCGT) system. The thickness-dependent magnetic domain size follows Kittel's law. The static spin textures and spin dynamics in FCGT nanoflakes were studied by Lorentz electron microscopy, variable-temperature magnetic force microscopy, micromagnetic simulations, and magnetotransport measurements. Current-induced skyrmion lattice motion was observed at room temperature, with a threshold current density, jth = 1 × 106 A/cm2. This discovery of a skyrmion lattice at room temperature in a noncentrosymmetric material opens the way for layered device applications and provides an ideal platform for studies of topological and quantum effects in 2D.
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Chinese indigenous pigs are favored for their rich flavor, which is generated through complex reactions involving lipid-oxidation-related flavor precursors. In this research, we characterized the aroma compounds and fatty acids of representative Chinese pig breeds by gas chromatography-olfactometry-mass spectrometry (GC-O-MS) and GC-ion mobility spectrometry (GC-IMS) with multivariate analysis. A total of 79 volatile compounds were identified, among which 15 compounds were selected as odorants in pork. According to multivariate statistical analysis, some odorants, including hexanal, 1-octen-3-ol, 2,3-octanedione, (E, E)-2,4-decadienal and dodecanal could be discriminative compounds explaining breed-originated differences in flavor profiles. As confirmed by partial least squares regression (PLS-R), some fatty acids, including C18:1n9c, C22:6n3 and C18:3n3, were major precursors for the formation of rich flavor in indigenous pig breeds. These results revealed that fatty acids and volatile compounds were breed-dependent, and the differences in flavor were related to the variance in the fatty acid content.
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Carne de Cerdo , Carne Roja , Compuestos Orgánicos Volátiles , Animales , China , Ácidos Grasos , Análisis Multivariante , Odorantes/análisis , Olfatometría/métodos , Carne Roja/análisis , Porcinos/genética , Compuestos Orgánicos Volátiles/análisisRESUMEN
Heat stress (HS) can be detrimental to the gut health of swine. Many negative outcomes induced by HS are increasingly recognized as including modulation of intestinal microbiota. In turn, the intestinal microbiota is a unique ecosystem playing a critical role in mediating the host stress response. Therefore, we aimed to characterize gut microbiota of pigs' exposure to short-term HS, to explore a possible link between the intestinal microbiota and HS-related changes, including serum cytokines, oxidation status, and intestinal epithelial barrier function. Our findings showed that HS led to intestinal morphological and integrity changes (villus height, serum diamine oxidase [DAO], serum D-lactate and the relative expressions of tight junction proteins), reduction of serum cytokines (interleukin [IL]-8, IL-12, interferon-gamma [IFN-γ]), and antioxidant activity (higher glutathione [GSH] and malondialdehyde [MDA] content, and lower superoxide dismutase [SOD]). Also, 16S rRNA sequencing analysis revealed that although there was no difference in microbial α-diversity, some HS-associated composition differences were revealed in the ileum and cecum, which partly led to an imbalance in the production of short-chain fatty acids including propionate acid and valerate acid. Relevance networks revealed that HS-derived changes in bacterial genera and microbial metabolites, such as Chlamydia, Lactobacillus, Succinivibrio, Bifidobacterium, Lachnoclostridium, and propionic acid, were correlated with oxidative stress, intestinal barrier dysfunction, and inflammation in pigs. Collectively, our observations suggest that intestinal damage induced by HS is probably partly related to the gut microbiota dysbiosis, though the underlying mechanism remains to be fully elucidated.
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Short-chain fatty acids (SCFAs) play an important role in the host system. Among SCFAs, butyrate has received particular attention for its large effect on host immunity, particularly in supplying energy to enterocytes and producing immune cells. Butyrate enters the cells through the Solute Carrier Family 5 Member 8 (SLC5A8) transporters, then works as a histone deacetylase inhibitor (HDAC) that inhibits the activation of Nuclear factor-κB (NF-κB), which down-regulates the expression of IL-1ß, IL-6, TNF-α. Meanwhile, butyrate acts as a ligand to activate G protein-coupled receptors GPR41, GPR43, and GPR109, promoting the expression of anti-inflammatory factors. Besides, it inhibits the proinflammatory factors. Further, it can also suppress the expression of chemokines and reduce inflammation to maintain host homeostasis. This paper reviews the research progress highlighting the potential function of butyrate as a factor impacting intestinal health, obesity and brain disorders.