Promotion of wound healing by acetate in murine colonic epithelial cell via c-Jun N-terminal kinase activation

When inflammatory stressors dramatically change, disease phenotypes may transform between autoimmune hematopoietic failure and myeloid neoplasms

Aplastic anemia (AA) and hypoplastic myelodysplastic syndrome are paradigms of autoimmune hematopoietic failure (AHF). Myelodysplastic syndrome and acute myeloid leukemia are unequivocal myeloid neoplasms (MNs). Currently, AA is also known to be a clonal hematological disease. Genetic aberrations typically observed in MNs are detected in approximately one-third of AA patients. In AA patients harboring MN-related genetic aberrations, a poor response to immunosuppressive therapy (IST) and an increased risk of transformation to MNs occurring either naturally or after IST are predicted. Approximately 10%-15% of patients with severe AA transform the disease phenotype to MNs following IST, and in some patients, leukemic transformation emerges during or shortly after IST. Phenotypic transformations between AHF and MNs can occur reciprocally. A fraction of advanced MN patients experience an aplastic crisis during which leukemic blasts are repressed. The switch that shapes the disease phenotype is a change in the strength of extramedullary inflammation. Both AHF and MNs have an immune-active bone marrow (BM) environment (BME). In AHF patients, an inflamed BME can be evoked by infiltrated immune cells targeting neoplastic molecules, which contributes to the BM-specific autoimmune impairment. Autoimmune responses in AHF may represent an antileukemic mechanism, and inflammatory stressors strengthen antileukemic immunity, at least in a significant proportion of patients who have MN-related genetic aberrations. During active inflammatory episodes, normal and leukemic hematopoieses are suppressed, which leads to the occurrence of aplastic cytopenia and leukemic cell regression. The successful treatment of underlying infections mitigates inflammatory stress-related antileukemic activities and promotes the penetration of leukemic hematopoiesis. The effect of IST is similar to that of treating underlying infections. Investigating inflammatory stress-powered antileukemic immunity is highly important in theoretical studies and clinical practice, especially given the wide application of immune-activating agents and immune checkpoint inhibitors in the treatment of hematological neoplasms.

The interplay between gingival crevicular fluid microbiome and metabolomic profile in intensively treated people with type 1 diabetes - a combined metagenomic/metabolomic approach cross-sectional study

Aims

This study aimed to assess the gingival crevicular fluid (GCF) microbiome and metabolome of adults with type 1 diabetes (T1D) treated with continuous subcutaneous insulin infusion (CSII).

Methods

In this cross-sectional study, the GCF of adults with T1D treated with CSII and non-diabetic controls were sampled, and metagenomic/metabolomic analyses were performed.

Results

In total, 65 participants with T1D and 45 healthy controls with a mean age of 27.05 ± 5.95 years were investigated. There were 22 cases of mild gingivitis (G) in the T1D group. There were no differences considering the Shannon and Chao indices and β-diversity between people with T1D and G, with T1D without G, and healthy controls. Differential taxa were identified, which were mainly enriched in people with T1D and G. Acetic acid concentration was higher in people with T1D, regardless of the presence of G, than in healthy controls. Propionic acid was higher in people with T1D and G than in healthy controls. Isobutyric and isovaleric acid levels were higher in individuals with T1D and G than in the other two subgroups. The concentration of valeric acid was lower and that of caproic acid was higher in people with T1D (regardless of gingival status) than in healthy controls.

Conclusions

The identification of early changes in periodontal tissues by targeting the microbiome and metabolome could potentially enable effective prevention and initial treatment of periodontal disease in people with T1D.

Immunological Regulation of Gut-Tropic Immune Cells by Extracellular Vesicles

The remarkable diversity of lymphocytes, essential components of the immune system, serves as an ingenious mechanism for maximizing the efficient utilization of limited host defense resources. While cell adhesion molecules, notably in gut-tropic T cells, play a central role in this mechanism, the counterbalancing molecular details have remained elusive. Conversely, we've uncovered the molecular pathways enabling extracellular vesicles secreted by lymphocytes to reach the gut's mucosal tissues, facilitating immunological regulation. This discovery sheds light on immune fine-tuning, offering insights into immune regulation mechanisms.

In Vitro Fermentation Characteristics of Fungal Polysaccharides Derived from Wolfiporia cocos and Their Effect on Human Fecal Microbiota

Gut microbiota has been described as a new 'organ' that interferes with host physiology by its metabolites produced from the utilization and biotransformation of undigested food components. Fu Ling (FL), the sclerotia of fungi Wolfiporia cocos, contains β-glucan, which is a known natural polysaccharide with strong medicinal efficacy. This study endeavors to evaluate the fermentability of FL and polysaccharides extracted from its sclerotia. An in vitro fermentation of structurally characterized FL and its β-glucan by human fecal microbiota was conducted. Total bacterial count, pH change, short-chain fatty acid profile and microbiota profile were assessed post-fermentation. FL containing over 70% of β-(1 → 3) and (1 → 6)-glucans with a low degree of branching of 0.24 could enhance acetic acid (a major microbial metabolite) production. Both FL and its extracted β-glucan had similar modulation on microbial composition. They enriched Phascolarctobacterium faecium, Bacteroides dorei and Parabacteroides distasonis, all of which are shown to possess anti-inflammatory effects. FL polysaccharide can be utilized as a natural whole food for its potential health benefits to human gut bacteria.

Tamarind Seed Polysaccharide Hydrolysate Ameliorates Dextran Sulfate Sodium-Induced Ulcerative Colitis via Regulating the Gut Microbiota

(1) Background: Ulcerative colitis (UC) is a disease caused by noninfectious chronic inflammation characterized by varying degrees of inflammation affecting the colon or its entire mucosal surface. Current therapeutic strategies rely on the suppression of the immune response, which is effective, but can have detrimental effects. Recently, different plant polysaccharides and their degradation products have received increasing attention due to their prominent biological activities. The aim of this research was to evaluate the mitigation of inflammation exhibited by tamarind seed polysaccharide hydrolysate (TSPH) ingestion in colitis mice. (2) Methods: TSPH was obtained from the hydrolysis of tamarind seed polysaccharide (TSP) by trifluoroacetic acid (TFA). The structure and physical properties of TSPH were characterized by ultraviolet spectroscopy (UV), thin-layer chromatography (TLC), fourier transform infrared spectroscopy (FT-IR), and High-Performance Liquid Chromatography and Electrospray Ionization Mass Spectrometry (HPLC-ESI/MS) analysis. Then, the alleviative effects of the action of TSPH on 2.5% dextran sodium sulfate (DSS)-induced colitis mice were investigated. (3) Results: TSPH restored pathological lesions in the colon and inhibited the over-secretion of pro-inflammatory cytokines in UC mice. The relative expression level of mRNA for colonic tight junction proteins was increased. These findings suggested that TSPH could reduce inflammation in the colon. Additionally, the structure of the gut microbiota was also altered, with beneficial bacteria, including Prevotella and Blautia, significantly enriched by TSPH. Moreover, the richness of Blautia was positively correlated with acetic acid. (4) Conclusions: In conclusion, TSPH suppressed colonic inflammation, alleviated imbalances in the intestinal flora and regulated bacterial metabolites. Thus, this also implies that TSPH has the potential to be a functional food against colitis.

Oleanolic acid stimulation of cell migration involves a biphasic signaling mechanism

Cell migration is a critical process for wound healing, a physiological phenomenon needed for proper skin restoration after injury. Wound healing can be compromised under pathological conditions. Natural bioactive terpenoids have shown promising therapeutic properties in wound healing. Oleanolic acid (OA), a triterpenoid, enhances in vitro and in vivo cell migration. However, the underlying signaling mechanisms and pathways triggered by OA are poorly understood. We have previously shown that OA activates epidermal growth factor receptor (EGFR) and downstream effectors such as mitogen-activated protein (MAP) kinase cascade and c-Jun N-terminal kinase (JNK), leading to c-Jun transcription factor phosphorylation, all of which are involved in migration. We performed protein expression or migration front protein subcellular localization assays, which showed that OA induces c-Jun activation and its nuclear translocation, which precisely overlaps at wound-edge cells. Furthermore, c-Jun phosphorylation was independent of EGFR activation. Additionally, OA promoted actin cytoskeleton and focal adhesion (FA) dynamization. In fact, OA induced the recruitment of regulator proteins to FAs to dynamize these structures during migration. Moreover, OA changed paxillin distribution and activated focal adhesion kinase (FAK) at focal adhesions (FAs). The molecular implications of these observations are discussed.

Maternal galactooligosaccharides supplementation programmed immune defense, microbial colonization and intestinal development in piglets

The benefits of galactooligosaccharides (GOS) in neonates have been confirmed. However, the effects of nutritional programming by maternal GOS intervention on microbial colonization and intestinal development in the offspring remain unclear. In the present study, late gestational sows were fed with GOS (10 g d^-1 added into the diet) or not until parturition, and the performances, immune status, microbiota composition and intestinal barriers in their piglets on day 21 were compared. GOS supplementation in pregnant sows improved their litter characteristics and the growth performance of their piglets during the neonatal stage (day 21), and elevated the plasma IgA levels in both sows and their piglets (P < 0.05). GOS intervention enriched fecal Alloprevotella and Ruminoclostridium_1 in gestational sows and vertically increased fecal Alloprevotella and Ruminococcaceae in their piglets (P < 0.05). Moreover, maternal GOS intervention increased fecal acetate (P < 0.05) and improved the intestinal barriers of their piglets by upregulating intestinal tight junctions (Occludin, Claudin-1, ZO-1), the goblet cell number and Mucin-2 (P < 0.05), which correlated positively with the colonized microbiota (P < 0.05). In summary, GOS supplementation for sows during late gestation nutritionally programmed maternal specific microbes and IgA of their offspring. This neonatal programming showed positive potential in promoting the intestinal barriers, immune defense, and growth performance of the piglets. Our findings provide evidence for maternal nutritional programming in neonates and insights for future application of GOS in maternal-neonatal nutrition.

Berberine inhibits intestinal epithelial barrier dysfunction in colon caused by peritoneal dialysis fluid by improving cell migration

ETHNOPHARMACOLOGICAL RELEVANCE

Berberine is generally extracted from Rhizoma Coptidis (Coptis chinensis Franch), a traditional Chinese medicine, which can be used in the treatment of intestinal diseases, respiratory infections and cardiovascular diseases. Berberine is especially effective for the treatment of gastrointestinal disorders such as diarrhea because of the effect of heat-clearing and detoxifying in traditional Chinese medicine theory.

AIM OF THE STUDY

This study aimed to examine the protective effect of berberine (BBR) on the damaged colonic epithelial barrier caused by peritoneal dialysis fluid (PDF).

METHODS

The damage to intestinal epithelial barrier was examined by intraperitoneally injecting 4.25% dextrose-containing PDF in mice and establishing a long-term PD model in rats with renal failure. Then, the therapeutic potential of berberine on PD-related colonic injuries was examined. T84 colonic epithelial cells were used to test the effect of PDF and berberine in vitro. The damaging effect of PDF and the protective effect of berberine were evaluated by histology staining, histofluorescence and transmission electron microscopy. The migration of colonic epithelial cell and actin-related protein 2 (Arp2) were tested by wound healing assay and Western blot to determine the possible mechanism in vitro.

RESULTS

PD administration induced intestinal epithelial barrier dysfunction in the colon, and berberine alleviated the injury by increasing the tight junction and adhesion junction protein, both in vivo and in vitro. Berberine could also improve the morphology of microvillus. In the wound healing assay, berberine exhibited the ability to promote cell migration, indicating that berberine could probably recover the function of intestinal epithelial cells when the intestinal epithelial barrier was damaged by the PDF.

CONCLUSIONS

The present study demonstrates that berberine can ameliorate intestinal epithelial barrier dysfunction in the colon caused by long-term PDF through improving cell migration.

Electroacupuncture preserves intestinal barrier integrity through modulating the gut microbiota in DSS-induced chronic colitis

AIMS

Electroacupuncture (EA) at ST36 has been verified to ameliorate experimental acute colitis. However, the effect of EA on chronic colitis and its mechanism has not yet been explored. This study aimed to assess the protective effect of EA against chronic colitis and the related mechanisms.

MAIN METHODS

Chronic colitis was induced by dextran sulfate sodium (DSS) in C57BL/6 mice, and EA was applied throughout the entire experiment. Colonic inflammation and intestinal barrier integrity were evaluated. Alterations in the gut microbiota were analyzed by 16S rRNA gene sequencing. The fecal microbiota transplantation (FMT) experiment was used to further confirm the effect of the gut microbiota on the barrier protective effect of EA. The potential molecular mechanisms were explored by western blotting.

KEY FINDINGS

(1) EA lowered the disease activity index (DAI) and histological scores, decreased the levels of TNFα, IL1β, IL6 and iNOS, and increased the IL10 level in DSS-induced chronic colitis. (2) EA upregulated the protein expression of ZO-1, Occludin, E-Cadherin and mucin2 (MUC2), reduced the apoptosis and proliferation of intestinal epithelial cells (IECs) and intestinal permeability. (3) EA enhanced the gut microbiota diversity and restored the community structure. (4) Both the low-frequency EA (LEA) FMT and high-frequency EA (HEA) FMT maintained the intestinal barrier integrity. (5) EA promoted activation of the mitogen activated protein kinase (MAPK) signaling pathway.

SIGNIFICANCE

EA can relieve chronic experimental colitis, and this effect may depend on activation of the MAPK signaling pathway through modulation of the gut microbiota to preserve the intestinal barrier.