The large Integral Field Spectroscopy surveys have allowed the classification of ionizing sources of emission lines on sub-kiloparsec scales. In this work, we define two non-parametric parameters, ...quiescence (Fq) and its concentration (Cq), to quantify the strength and the spatial distribution of the quenched areas, respectively, traced by the LI(N)ER regions with low EW(H ). With these two measurements, we classify MaNGA galaxies into inside-out and outside-in quenching types according to their locations on the Fq versus Cq plane and we measure the fraction of inside-out (outside-in) quenching galaxies as a function of halo mass. We find that the fraction of galaxies showing inside-out quenching increases with halo mass, irrespective of stellar mass or galaxy type (satellites versus centrals). In addition, high-stellar-mass galaxies exhibit a greater fraction of inside-out quenching compared to low-stellar-mass ones in all environments. In contrast, the fraction of outside-in quenching does not depend on halo mass. Our results suggest that morphological quenching may be responsible for the inside-out quenching seen in all environments. On the other hand, the flat dependence of the outside-in quenching on halo mass could be a mixed result of ram pressure stripping and galaxy mergers. Nevertheless, for a given environment and stellar mass, the fraction of inside-out quenching is systematically greater than that of outside-in quenching, suggesting that inside-out quenching is the dominant quenching mode in all environments.
Visceral hypersensitivity (VH) and gut microbiota dysbiosis significantly contribute to the occurrence and development of irritable bowel syndrome (IBS), exacerbated by stress. Apigenin, a natural ...flavonoid derived from plants, possesses a range of beneficial properties. However, additional research is necessary to investigate its potential in alleviating symptoms of IBS and elucidating its underlying mechanisms of action. Our study confirms that apigenin effectively reverses mast cell and microglial activation, regulates the composition and abundance of the gut microbiota, improves intestinal barrier function in rats induced with water-avoidance stress, and mitigates VH and colonic hypermotility. Furthermore, in vitro studies suggest a potential role of dysbiotic gut microbiota in activating mast cells at the cellular level. Notably, apigenin inhibits mast cell degranulation through the toll-like receptor 4 (TLR4) / myeloid differentiation primary response gene 88 (MyD88) / nuclear factor-kappa B (NF-κB) pathway. In conclusion, this study discusses the potential therapeutic effects of apigenin in alleviating VH and modulating the gut-brain axis in water-avoidance stress rats, providing a novel or alternative treatment approach for IBS.
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(
) has been reported to have the potential to regulate gut motility. The aim of this experiment was to explore the possible function of
in gut hypermotility elicited by repeated water avoidance ...stress (WAS).
Adult male Wistar rats (
= 24) were divided into one of the following three groups: control (C), NS (normal saline) + WAS group (N), and
+ WAS group (S). A diarrhea-predominant irritable bowel syndrome (IBS-D) model in rats was induced using the WAS method. Gut motility was evaluated by stool pellet expulsion per hour. The contractile activity of the colonic muscle strips was measured using an RM6240 multichannel physiological signal instrument. qRT-PCR and immunohistochemistry were used to assess Toll-like receptor 4 (TLR4) expression in colon tissue. ELISA was used to measure the level of cytokines in the serum and colonic tissue. Also, the microbiota composition was determined using high-throughput 16S rRNA sequencing.
The results showed that oral
decreased the WAS-induced increased defecation and colonic hypermotility
. Furthermore,
also decreased the contractile amplitude of colonic circular muscle (CM) and longitudinal muscle (LM) strips in a dose-dependent manner
. Repeated WAS increased TLR4 expression, but
reversed it.
also reduced interleukin-6 (IL-6), IL-1β, and interferon-γ (IFN-γ) levels in serum and colonic tissue, while increasing IL-10 levels in colonic tissue. Meanwhile, the rats from the NS + WAS group had decreased microbiota diversity and had lower relative abundances of Patescibacteria, Epsilonbacteraeota, Cyanobacteria, and Turicibacter compared with controls. The rats in the
+ WAS group showed a tendency to increase the relative abundance of Blautia when compared to control rats and had lower relative abundances of Acidobacteria and Anaerostipes compared with the NS + WAS group.
Our findings demonstrated that
improved colonic hypermotility in rats, reversed the high-expression of TLR4 in the colon caused by repeated WAS, modulated cytokines in the colon and serum, and altered the gut microbiota, indicating that
may be useful for IBS-D.
We use the Herschel SPIRE color–color diagram to study the spectral energy distribution (SED) and the redshift estimation of high-z galaxies. We compiled a sample of 57 galaxies with ...spectroscopically confirmed redshifts and SPIRE detections in all three bands at z = 2.5–6.4, and compared their average SPIRE colors with SED templates from local and high-z libraries. We find that local SEDs are inconsistent with high-z observations. The local calibrations of the parameters need to be adjusted to describe the average colors of high-z galaxies. For high-z libraries, the templates with an evolution from z = 0 to 3 can well describe the average colors of the observations at high redshift. Using these templates, we defined color cuts to divide the SPIRE color–color diagram into different regions with different mean redshifts. We tested this method and two other color cut methods using a large sample of 783 Herschel-selected galaxies, and find that although these methods can separate the sample into populations with different mean redshifts, the dispersion of redshifts in each population is considerably large. Additional information is needed for better sampling.
Scope
Irritable bowel syndrome (IBS) is an intestinal disorder, whose symptoms can be alleviated by certain dietary phytochemicals. This study explores the role and potential mechanisms of a natural ...flavonoid luteolin (LUT) in alleviating the excessive motility of colonic smooth muscles and reducing oxidative stress in IBS with diarrhea (IBS‐D) rats.
Methods and results
LUT reduces excessive intestinal motility and lowers reactive oxygen species (ROS) levels in a water avoidance stress (WAS) rat model. Moreover, LUT increases the protein expression levels of nuclear factor erythroid 2‐related factor 2 (Nrf2) and heme oxygenase‐1 (HO‐1), activates the nuclear translocation of Nrf2, and greatly reduces the hydrogen peroxide (H2O2)‐induced oxidative damage in intestinal epithelial cells.
Conclusions
LUT, a phyto‐active component, protects against excessive intestinal motility and diarrhea by regulating the Nrf2 signaling pathway and effectively reduces oxidative stress damage in the colon.
Luteolin inhibits colonic hypermobility and reduces ROS levels in WAS rats, upregulates the protein expression levels of Nrf2 and HO‐1, and promotes Nrf2 nuclear ectopic. However, this effect is partially reversed by the Nrf2 selective inhibitor.
We present preliminary results of the spectral analysis on the radial distributions of the star formation history in both a galaxy merger and a spiral isolated galaxy observed with MaNGA. We find ...that the central part of the isolated galaxy is composed by older stellar population (~2 Gyr) than in the outskirts (~7 Gyr). Also, the time-scale is gradually larger from 1 Gyr in the inner part to 3 Gyr in the outer regions of the galaxy. In the case of the merger, the stellar population in the central region is older than in the tails, presenting a longer time-scale in comparison to central part in the isolated galaxy. Our results are in agreement with a scenario where spiral galaxies are built from inside-out. In the case of the merger, we find evidence that interactions enhance star formation in the central part of the galaxy.
Apelin is a novel neuropeptide identified as the endogenous ligand for the apelin receptor. Apelin and its receptor are widely distributed in the gastrointestinal tract. Studies have reported that ...apelin-13 is involved in modulating gastrointestinal motility; however, the evidence is insufficient and the relevant mechanism is still not fully clear. Consequently, our study designed to explore the effect induced by exogenous apelin-13, to analyze the mechanism of action in isolated rat colons and colonic smooth muscle cells. The spontaneous contractions of colonic smooth muscle strips from rat were measured in an organ bath system. L-type calcium currents and large conductance Ca2+-activated K+ (BKCa) currents in rat colonic smooth muscle cells were investigated using the electrophysiological patch-clamp technique.
Apelin-13 decreased the spontaneous contractile activity of colonic smooth muscle strips in a dose-dependent manner, and the inhibitory effect was not abolished by tetrodotoxin. The electrophysiological recordings revealed that apelin-13 reduced the crest currents of L-type calcium in a concentration-dependent manner in colonic smooth muscle cells at the test potential of 0 mV. Moreover, apelin-13 moved the current-voltage (I–V) curves of L-type calcium channels upward, but did not change their contour. Furthermore, the characteristics of L-type calcium channels with steady-state activation and steady-state inactivation were not significantly changed. Similarly, application of apelin-13 also significantly decreased BKCa currents in a concentration-dependent manner. In conclusion, apelin-13 inhibited the spontaneous contractile activity of isolated rat colons via the suppression of L-type calcium channels and BKCa channels in colonic smooth muscle cells.
Agricultural mulching is an important input for modern agricultural production and plays an important role in guaranteeing food security worldwide. At present, polyethylene (PE) mulching is still ...commonly used in agricultural production in most countries around the world, which is non-biodegradable, and years of mulching have caused serious agricultural white pollution. Lignin is one of the three major components of plant cell walls, and it is also the main renewable natural aromatic compounds in nature. Lignin-based composite film materials are green, biodegradable, and show good prospects for development in the field of agricultural mulch. This paper introduces the types, structure, and application status of lignin, summarizes the preparation of lignin-based composite film materials and its latest research progress, focuses on the types, preparation methods, and application examples of lignin-based agricultural mulching, and looks forward to the future development prospects of lignin-based agricultural mulching.
Background
Phosphodiesterase (PDE) inhibition has been reported to play a role in regulating gut motility, but the evidence is insufficient, and the mechanism remains unknown. The aim of this study ...was to investigate the possible role of phosphodiesterase‐4 (PDE4) inhibitor rolipram in water avoidance stress‐induced colonic hypermotility.
Methods
A rat model of irritable bowel syndrome (IBS) with diarrhea (IBS‐D) was established by water avoidance stress (WAS). Intestinal motility was assessed by fecal pellets expulsion per hour. The cyclic adenosine monophosphate (cAMP) and nitric oxide (NO) level in colon tissue were detected using ELISA assay and the Griess test, respectively. Western blotting was performed to assess the protein level of PDE, PKA/p‐CREB, and neuronal nitric oxide synthase (nNOS) in the colon. To determine the role of rolipram in gut motility, the rats of the WAS + Rolipram and Rolipram group were injected with rolipram intraperitoneally. The colonic contractile activity was recorded with a RM6240 multichannel physiological signal system.
Key Results: WAS‐induced gastrointestinal hypermotility and increased defecation in rats. After repeated stress, protein levels of PDE4 in the colon were promoted while PKA/p‐CREB and nNOS were highly decreased. cAMP content in colon tissue did not change significantly. However, NO content decreased after WAS, and rolipram partly enhanced NO in WAS‐exposed rats. In addition, intraperitoneal injection of rolipram partly inhibited the colonic motility in vivo. Meanwhile, we observed rolipram inhibited the contraction of colonic smooth muscle strips, and this inhibitory effect was abolished by Nω‐Nitro‐L‐arginine (L‐NNA), a nitric oxide synthase (NOS) inhibitor, tetrodotoxin (TTX), a blocker of neuronal voltage‐dependent Na+ channels, Rp‐Adenosine 3’,5'‐cyclic monophosphorothioate triethylammonium salt hydrate (Rp‐cAMPS), an antagonist of cAMP.
Conclusions and Inferences: Rolipram could relieve stress‐induced gastrointestinal hypermotility. This effect may be partly through the cAMP‐PKA‐p‐CREB pathway and NO pathway.
The PDE4 isozyme located in the colon, and the inhibition of PDE4 isozyme could activate the downstream cAMP‐PKA‐p‐CREB pathway and NO pathway, thus leading to the relaxation of colonic smooth muscle.
Purpose: Ulcerative colitis (UC) patients have disturbances in the microbiota-gut-brain axis, and mast cells are important components of this axis. The mast cell-specific receptor Mrgprb2 has effects ...on host defense against bacterial infection and neurogenic inflammation, which may help mast cells act on the axis. This study analyzed how Mrgprb2 participates in the pathogenesis of UC by affecting the microbiota-gut-brain axis. Materials and Methods: Mrgprb2 knockout (b2KO) mice and wild-type (WT) mice were fed 2% (w/v) dextran sulfate sodium (DSS) in drinking water for 7 days, which was then replaced with normal water for 14 days. This cycle was repeated three times. Feces were collected on Days 21, 42, and 63 for intestinal microbiota analysis, and mice were euthanized on Day 64. Hypothalamus, amygdala and colon tissues were removed and analyzed. Results: Compared with WT mice, B2KO mice exhibited increased weight loss, colon shortening and colonic pathological damage after colitis induction. Analysis of the intestinal microbiota showed that b2KO mice with colitis had a significant decrease in the abundance and diversity, as well as an increase in Allobaculum and a decrease in norank_f__Muribaculaceae and Ileibacterium. In colon tissues, the expression of mucin 2 (MUC2) and junctional adhesion molecule A (JAM-A) in b2KO mice was reduced, and oxidative stress levels were higher. B2KO mice with colitis had higher corticotropin-releasing hormone (CRH), corticotropin-releasing hormone receptor 1 (CRHR1), neuropeptide Y (NPY) and brain-derived neurotrophic factor (BDNF) mRNA levels in hypothalamus tissues and glucocorticoid receptor mRNA levels in the amygdala. Conclusion: In the microbiota-gut-brain axis, Mrgprb2 was involved in regulating the intestinal microbiota composition, intestinal barrier and oxidative stress levels, and was related to stress regulation, which might help to explain the pathogenesis of UC.
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