Alginate Oligosaccharides Ameliorate DSS-Induced Colitis through Modulation of AMPK/NF-κB Pathway and Intestinal Microbiota

Alginate Oligosaccharides Enhance Gut Microbiota and Intestinal Barrier Function, Alleviating Host Damage Induced by Deoxynivalenol in Mice

BACKGROUND

Alginate oligosaccharides (AOS) exhibits notable effects in terms of anti-inflammatory, antibacterial, and antioxidant properties. Deoxynivalenol (DON) has the potential to trigger intestinal inflammation by upregulating pro-inflammatory cytokines and apoptosis, thereby compromising the integrity of the intestinal barrier function and perturbing the balance of the gut microbiota.

OBJECTIVES

We assessed the impact of AOS on mitigating DON-induced intestinal damage and systemic inflammation in mice.

METHODS

After a 1-wk acclimatization period, the mice were divided into 4 groups. For 3 wk, the AOS and AOS + DON groups were gavaged daily with 200 μL of AOS [200 mg/kg body weight (BW)], whereas the CON and DON groups received an equivalent volume of sterile Phosphate-Buffered Saline (PBS). Subsequently, for 1 wk, the DON and AOS + DON groups received 100 μL of DON (4.8 mg/kg BW) daily, whereas the control (CON) and AOS groups continued receiving PBS.

RESULTS

After administering DON via gavage to mice, there was a significant decrease (P < 0.05) in body weights compared with the CON group. Interestingly, AOS exhibited a tendency to mitigate this weight loss in the AOS + DON group. In the feces of mice treated with both AOS and DON, the concentration of DON significantly increased (P < 0.05) compared with the DON group alone. Histological analysis revealed that DON exposure caused increased intestinal damage, including shortened villi and eroded epithelial cells, which was ameliorated by presupplementation with AOS, alleviating harm to the intestinal barrier function. In both jejunum and colon tissues, DON exposure significantly reduced (P < 0.05) the expression of tight junction proteins (claudin and occludin in the colon) and the mucin protein mucin 2, compared with the CON group. Prophylactic administration of AOS alleviated these reductions, thereby improving the expression levels of these key proteins. Additionally, AOS supplementation protected DON-exposed mice by increasing the abundance of probiotics such as Bifidobacterium, Faecalibaculum, and Romboutsia. These gut microbes are known to enhance (P < 0.05) anti-inflammatory responses and the production of short-chain fatty acids (SCFAs), including total SCFAs, acetate, and valerate, compared with the DON group.

CONCLUSIONS

This study unveils that AOS not only enhances gut microbiota and intestinal barrier function but also significantly mitigates DON-induced intestinal damage.

Potential of Fiber and Probiotics to Fight Against the Effects of PhIP + DSS-Induced Carcinogenic Process of the Large Intestine

We determined the in vivo counteracting effect of fiber and probiotic supplementation on colonic mucosal damage and alterations in gut microbiota caused by 2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine (PhIP) and sodium dextran sulfate (DSS). Male Fischer-344 rats were randomly divided into 4 groups: control (standard diet), PhIP + DSS group (standard diet + PhIP + DSS), fiber (fiber diet + PhIP + DSS), and probiotic (probiotic diet + PhIP + DSS). The intake of PhIP + DSS for 3 weeks induced colonic mucosal erosion, crypt loss, and inflammation, and the distal colon was more severely damaged. Fiber alleviated colonic mucosal damage by reducing crypt loss and inflammation, while the probiotic increased colon length. The intake of PhIP + DSS increased the fecal relative abundance of Clostridia UCG014 along the intervention, in contrast to the lower abundances of these taxa found after PhIP + DSS administration in the rats supplemented with probiotics or fiber. Fiber supplementation mitigated the histological damage caused by PhIP + DSS shifting the gut microbiota toward a reduction of pro-inflammatory taxa.

Neuregulin-4 alleviates isoproterenol (ISO)-induced cardial remodeling by inhibiting inflammation and apoptosis via AMPK/NF-κB pathway

Cardiac remodeling refers to the abnormal changes in cardiac structure and function caused by various pathological conditions. It is an inevitable pathological process in the occurrence and development of heart failure and is related to a variety of cardiovascular diseases. Inflammation and apoptosis are critical pathological processes involved in cardiac remodeling. Neuregulin 4 (Nrg 4) is an adipokine produced primarily by brown adipose tissue that may play a protective role in a variety of inflammatory diseases. The aim of this study was to investigate whether Nrg4 can delay the progression of cardiac remodeling by regulating AMPK/NF-κB pathway, inhibiting inflammation and apoptosis. In our study, we established a model of cardiac remodeling in mice after 14 days of isoproterenol (ISO) intervention, and then gave Nrg4 treatment for another 4 weeks. The cardiac function, the degree of myocardial hypertrophy and myocardial fibrosis of the mice were observed. At the same time, the levels of apoptosis-related proteins (Bax,Bcl-2,Caspase-3), IL-6,IL-Iβ and TNF-α, as well as the activation level of AMPK/NF-κB signaling pathway were evaluated.Nrg4 alleviated ISO-induced cardiac dysfunction, cardiac hypertrophy and fibrosis in mice. Nrg4 also attenuated ISO-induced apoptosis and reduces levels of inflammatory factors to protect ISO-induced myocardial damage. At the same time, the effect of Nrg4 on AMPK/NF-κB pathway was measured in vivo and in vitro. The administration of an AMPK inhibitor was found to reverse the anti-hypertrophy, anti-inflammatory, and anti-apoptotic effects of Nrg4. Our findings suggest that Nrg4 may play a protective role in cardiac remodeling by inhibiting inflammation and apoptosis via AMPK/NF-κB pathway.

The role of alginate oligosaccharide on boar semen quality: A research review

Alginate is the general term of a polysaccharide which is widely used in the area of pharmaceutics and the food industry and is known for its unique biological activities. However, due to the low water solubility and large viscosity of alginate, its development and utilization in the agricultural field are limited. Alginate oligosaccharide (AOS) is a degradable product derived from alginate and has attracted much attention in recent years because of its specific characteristics such as a low molecular weight, high water solubility, and non-toxicity. Boar semen quality, which is affected by various factors, is an important indicator for measuring reproductive performance of boars. With the development of artificial insemination technology, high quality semen has been more and more important. Therefore, increasing semen quality is an important means to improve the reproductive performance in swine industry. In this research review, we used the PubMed database and Google Scholar and web of science to search for relevant literature on the topic of AOS in relation to boar semen quality. Key words used were alginate oligosaccharide, boars, semen quality, microbiota and metabolites. The purpose of this review article was to describe the current knowledge on the relationship between AOS and boar semen quality, and provide an overview of solutions for the decline in the boar semen quality in specific conditions. Based on the existing literature, it is evident that AOS can be used as a new type of food additive. This review paper provides a theoretical basis for the production of high-quality boar sperm and, suggests that, in the future, AOS can even aid in treating human infertility.

The therapeutic effect and possible mechanisms of alginate oligosaccharide on metabolic syndrome by regulating gut microbiota

Metabolic syndrome (MetS) is a disease condition incorporating the abnormal accumulation of various metabolic components, including overweight or abdominal obesity, insulin resistance and abnormal glucose tolerance, hypertension, atherosclerosis, or dyslipidemia. It has been proved that the gut microbiota and microbial-derived products play an important role in regulating lipid metabolism and thus the onset and development of MetS. Previous studies have demonstrated that oligosaccharides with prebiotic effects, such as chitosan oligosaccharides, can regulate the structure of the microbial community and its derived products to control weight and reduce MetS associated with obesity. Alginate oligosaccharides (AOS), natural products extracted from degraded alginate salts with high solubility and extensive biological activity, have also been found to modulate gut microbiota. This review aims to summarize experimental evidence on the positive effects of AOS on different types of MetS while providing insights into mechanisms through which AOS regulates gut microbiota for preventing and treating MetS.

HIF-1α Pathway Orchestration by LCN2: A Key Player in Hypoxia-Mediated Colitis Exacerbation

In this study, we investigated the role of hypoxia in the development of chronic inflammatory bowel disease (IBD), focusing on its impact on the HIF-1α signaling pathway through the upregulation of lipocalin 2 (LCN2). Using a murine model of colitis induced by sodium dextran sulfate (DSS) under hypoxic conditions, transcriptome sequencing revealed LCN2 as a key gene involved in hypoxia-mediated exacerbation of colitis. Bioinformatics analysis highlighted the involvement of crucial pathways, including HIF-1α and glycolysis, in the inflammatory process. Immune infiltration analysis demonstrated the polarization of M1 macrophages in response to hypoxic stimulation. In vitro studies using RAW264.7 cells further elucidated the exacerbation of inflammation and its impact on M1 macrophage polarization under hypoxic conditions. LCN2 knockout cells reversed hypoxia-induced inflammatory responses, and the HIF-1α pathway activator dimethyloxaloylglycine (DMOG) confirmed LCN2's role in mediating inflammation via the HIF-1α-induced glycolysis pathway. In a DSS-induced colitis mouse model, oral administration of LCN2-silencing lentivirus and DMOG under hypoxic conditions validated the exacerbation of colitis. Evaluation of colonic tissues revealed altered macrophage polarization, increased levels of inflammatory factors, and activation of the HIF-1α and glycolysis pathways. In conclusion, our findings suggest that hypoxia exacerbates colitis by modulating the HIF-1α pathway through LCN2, influencing M1 macrophage polarization in glycolysis. This study contributes to a better understanding of the mechanisms underlying IBD, providing potential therapeutic targets for intervention.

Expression of MAF bZIP transcription factor B protects against ulcerative colitis through the inhibition of the NF-κB pathway

PURPOSE

The aim of this study was to explore whether MAF bZIP transcription factor B (MAFB) might alleviate ulcerative colitis (UC) in dextran sulfate sodium (DSS)-induced mice and LPS-induced IEC-6 cells.

METHODS

UC in vivo and in vitro model was established by using DSS and LPS, respectively. The mice body weight and disease activity index (DAI) score were recorded daily, and colon length was measured. Moreover, the permeability was evaluated utilizing a fluorescein isothiocyanate dextran (FITC-Dextran) probe. Histopathological changes of DSS-induced colitis mice was assessed utilizing H&E staining. Next, qRT-PCR was performed to detect IL-1β, IL-6, TNF-α, and IL-10 level in in vivo and in vitro. Furthermore, the level of MDA, SOD, CAT, and GSH were evaluated in colon tissues. Besides, the expressions of tight junction proteins and NF-κB pathway relative proteins were examined in colitis mice and IEC-6 cells using western blot, immunohistochemistry and immunofluorescence.

RESULTS

MAFB level was downregulated in DSS-induced colitis mice. Moreover, the upregulation of MAFB protected mice from DSS-induced colitis by suppressing DSS-induced inflammation, oxidative stress, and intestinal barrier impairment. We also demonstrated that the upregulation of MAFB inactivated NF-κB pathway in DSS-caused colitis mice. Subsequently, we observed that MAFB upregulation could inhibit LPS-caused epithelial barrier impairment and inflammation in IEC-6 cells. Additionally, MAFB overexpression could suppress the activation of NF-κB pathway in IEC-6 cells.

CONCLUSION

The upregulation of MAFB could protect against UC via the suppression of inflammation and the intestinal barrier impairment through inhibiting the NF-κB pathway.

Auraptene Mitigates Colitis Induced by Dextran Sulfate Sodium in Mice by Regulating Specific Intestinal Flora and Repairing the Intestinal Barrier

Auraptene (AUT) is widely known to possess both antioxidant and anti-inflammatory properties. This study attempted to evaluate the protective effects of AUT in dextran sodium sulfate (DSS)-induced colitis in mice and to determine the underlying molecular mechanisms. Our results suggest that AUT substantially minimizes the severity and worsening of DSS-induced colitis in mice, indicated by the lengthening of the colon, lower disease activity index, reduced oxidation levels, and attenuated inflammatory factors. Molecular studies revealed that AUT reduces the nuclear translocation of nuclear factor-κB (NF-κB), thereby inhibiting the expression of inflammatory factors. Additionally, AUT promotes the diversity of the intestinal flora in mice with colitis by increasing the number of beneficial bacteria such as Lactobacillaceae and lowering the number of harmful bacteria. In conclusion, AUT mitigates DSS-induced colitis by maintaining the integrity of the intestinal barrier and modulating the levels of the intestinal microbial species.

Alginate oligosaccharide assimilation by gut microorganisms and the potential role in gut inflammation alleviation

Dietary fiber metabolism by gut microorganisms plays important roles in host physiology and health. Alginate, the major dietary fiber of daily diet seaweeds, is drawing more attention because of multiple biological activities. To advance the understanding of alginate assimilation mechanism in the gut, we show the presence of unsaturated alginate oligosaccharides (uAOS)-specific alginate utilization loci (AUL) in human gut microbiome. As a representative example, a working model of the AUL from the gut microorganism Bacteroides clarus was reconstructed from biochemistry and transcriptome data. The fermentation of resulting monosaccharides through Entner-Doudoroff pathway tunes the metabolism of short-chain fatty acids and amino acids. Furthermore, we show that uAOS feeding protects the mice against dextran sulfate sodium-induced acute colitis probably by remodeling gut microbiota and metabolome.

IMPORTANCE

Alginate has been included in traditional Chinese medicine and daily diet for centuries. Recently discovered biological activities suggested that alginate-derived alginate oligosaccharides (AOS) might be an active ingredient in traditional Chinese medicine, but how these AOS are metabolized in the gut and how it affects health need more information. The study on the working mechanism of alginate utilization loci (AUL) by the gut microorganism uncovers the role of unsaturated alginate oligosaccharides (uAOS) assimilation in tuning short-chain fatty acids and amino acids metabolism and demonstrates that uAOS metabolism by gut microorganisms results in a variation of cell metabolites, which potentially contributes to the physiology and health of gut.

Alginate Oligosaccharide Alleviates Lipopolysaccharide-Induced Apoptosis and Inflammatory Response of Rumen Epithelial Cells through NF-κB Signaling Pathway

AOS alleviates inflammatory responses; however, whether it exerts an effect on the rumen or regulates rumen inflammatory reaction remains unknown. In this study, firstly, the ovine ruminal epithelial cells (ORECs) were treated with 0, 200, 400, 600, and 800 µg/mL AOS, hoping to explore whether AOS hurt cell health. The results showed that compared with the AOS-0 group, the AOS-400 group could significantly increase (p < 0.05) cell viability, reduce (p < 0.05) reactive oxygen species (ROS) and interleukin (IL)-6 content, and have no adverse effect on cells. Secondly, we used LPS to construct an in vitro inflammatory model of rumen epithelial cells and then explored the protective role of AOS on rumen epithelial cells. The study was divided into three groups: the control group (CON), LPS, and LPS + AOS. The results demonstrated that the LPS + AOS group significantly increased the cell viability and reduced the ROS level in comparison with the LPS group (p < 0.05). Pretreatment with AOS also repressed (p < 0.05) the secretion of IL-1β, IL-6, IL-8, and immunoglobulin (Ig)A from ORECs in the culture medium following LPS. In terms of tight junction (TJ) proteins, AOS treatment also significantly increased (p < 0.05) the zonula occludens 1 (ZO-1) and Occludin expression. The apoptosis rate, Caspase3, Caspase9, BAD, and BCL-2/BAX were decreased (p < 0.05) after AOS treatment, and the expression of BCL-2 was increased (p < 0.05). In addition, the expressions of Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88), and nuclear factor-κB (NF-κB) were inhibited (p < 0.05) with the addition of AOS. At the protein level, pretreatment of AOS decreased (p < 0.05) the expression of MyD88 and the phosphorylation level of inhibitor κB α (IκBα) after the LPS challenge. Taken together, our results indicated that AOS could alleviate the LPS-induced apoptosis and inflammatory response of rumen epithelial cells through the NF-κB signaling pathway, which may be a promising strategy for treating apoptosis and inflammation in sheep breeding.

[UBE2W overexpression promotes proliferation of intestinal mucosal cells in mice with chemically induced colitis]

OBJECTIVE

To explore the effect of UBE2W overexpression on proliferation of intestinal mucosal cells in a mouse model of dextran sulfate sodium (DSS)-induced colitis.

METHODS

In a mouse model of colitis induced by exposure to DSS in drinking water, UBE2W expression in the colon tissue was detected by RT-PCR and Western blotting. Ten mouse models of colitis were randomized for injection of adenovirus AAV2/9 myc-UBE2W or control AAV2/9 via the tail vein (n=5), and the changes in body weight were recorded and the histological score of the colon were graded using HE staining. Ki67 and BrdU expressions in the colon mucosal cells were detected with immunohistochemistry. The effect of UBE2W overexpression on proliferation of 293T and HCT116 cells was observed using CCK-8 kit.

RESULTS

Compared with normal mice, the mouse models with DSS-induced colitis showed significantly lowered expressions of UBE2W mRNA and protein in the colon tissues. The mouse models with AAV2/9 myc-UBE2W injection had a lower body weight loss than those with control AAV2/9 injection, and the difference was the most distinct on days 9 and 10 (P < 0.05). AAV2/9 myc-UBE2W injection significantly decreased the histological score (P < 0.05) and increased Ki67 and BrdU expressions in the colon mucosal cells in the mouse models (P < 0.05). In both 293T and HCT116 cells, UBE2W overexpression significantly promoted cell proliferation at 72 h and 96 h after plasmid transfection (P < 0.05).

CONCLUSION

UBE2W overexpression provide protection of the colon mucosal cells and promotes recovery of colitis in mice possibly by promoting proliferation of the colon mucosal cells.

The role of AMPK in macrophage metabolism, function and polarisation

AMP-activated protein kinase (AMPK) is a ubiquitous sensor of energy and nutritional status in eukaryotic cells. It plays a key role in regulating cellular energy homeostasis and multiple aspects of cell metabolism. During macrophage polarisation, AMPK not only guides the metabolic programming of macrophages, but also counter-regulates the inflammatory function of macrophages and promotes their polarisation toward the anti-inflammatory phenotype. AMPK is located at the intersection of macrophage metabolism and inflammation. The metabolic characteristics of macrophages are closely related to immune-related diseases, infectious diseases, cancer progression and immunotherapy. This review discusses the structure of AMPK and its role in the metabolism, function and polarisation of macrophages. In addition, it summarises the important role of the AMPK pathway and AMPK activators in the development of macrophage-related diseases.

Alginate oligosaccharide extends the service lifespan by improving the sperm metabolome and gut microbiota in an aging Duroc boars model

Introduction

Alginate oligosaccharide (AOS), as a natural non-toxic plant extract, has been paid more attention in recent years due to its strong antioxidant, anti-inflammatory, and even anti-cancer properties. However, the mechanism by which AOS affects animal reproductive performance is still unclear.

Methods

The purpose of this study is to use multi-omics technology to analyze the effects of AOS in extending the service lifespan of aging boars.

Results

The results showed that AOS can significantly improve the sperm motility (p < 0.05) and sperm validity rate (p < 0.001) of aging boars and significantly reduce the abnormal sperm rate (p < 0.01) by increasing the protein levels such as CatSper 8 and protein kinase A (PKA) for semen quality. At the same time, AOS significantly improved the testosterone content in the blood of boars (p < 0.01). AOS significantly improved fatty acids such as adrenic acid (p < 0.05) and antioxidants such as succinic acid (p < 0.05) in sperm metabolites, significantly reducing harmful substances such as dibutyl phthalate (p < 0.05), which has a negative effect on spermatogenesis. AOS can improve the composition of intestinal microbes, mainly increasing beneficial bacteria Enterobacter (p = 0.1262) and reducing harmful bacteria such as Streptococcus (p < 0.05), Prevotellaceae_UCG-001 (p < 0.05), and Prevotellaceae_NK3B31_group (p < 0.05). Meanwhile, short-chain fatty acids in feces such as acetic acid (p < 0.05) and butyric acid (p < 0.05) were significantly increased. Spearman correlation analysis showed that there was a close correlation among microorganisms, sperm metabolites, and sperm parameters.

Discussion

Therefore, the data indicated that AOS improved the semen quality of older boars by improving the intestinal microbiota and sperm metabolome. AOS can be used as a feed additive to solve the problem of high elimination rate in large-scale boar studs.

Structure-Activity Relationships of Low Molecular Weight Alginate Oligosaccharide Therapy against Pseudomonas aeruginosa

Low molecular weight alginate oligosaccharides have been shown to exhibit anti-microbial activity against a range of multi-drug resistant bacteria, including Pseudomonas aeruginosa. Previous studies suggested that the disruption of calcium (Ca2+)-DNA binding within bacterial biofilms and dysregulation of quorum sensing (QS) were key factors in these observed effects. To further investigate the contribution of Ca2+ binding, G-block (OligoG) and M-block alginate oligosaccharides (OligoM) with comparable average size DPn 19 but contrasting Ca2+ binding properties were prepared. Fourier-transform infrared spectroscopy demonstrated prolonged binding of alginate oligosaccharides to the pseudomonal cell membrane even after hydrodynamic shear treatment. Molecular dynamics simulations and isothermal titration calorimetry revealed that OligoG exhibited stronger interactions with bacterial LPS than OligoM, although this difference was not mirrored by differential reductions in bacterial growth. While confocal laser scanning microscopy showed that both agents demonstrated similar dose-dependent reductions in biofilm formation, OligoG exhibited a stronger QS inhibitory effect and increased potentiation of the antibiotic azithromycin in minimum inhibitory concentration and biofilm assays. This study demonstrates that the anti-microbial effects of alginate oligosaccharides are not purely influenced by Ca2+-dependent processes but also by electrostatic interactions that are common to both G-block and M-block structures.

Recent progress in plant-derived polysaccharides with prebiotic potential for intestinal health by targeting gut microbiota: a review

Natural products of plant origin are of high interest and widely used, especially in the food industry, due to their low toxicity and wide range of bioactive properties. Compared to other plant components, the safety of polysaccharides has been generally recognized. As dietary fibers, plant-derived polysaccharides are mostly degraded in the intestine by polysaccharide-degrading enzymes secreted by gut microbiota, and have potential prebiotic activity in both non-disease and disease states, which should not be overlooked, especially in terms of their involvement in the treatment of intestinal diseases and the promotion of intestinal health. This review elucidates the regulatory effects of plant-derived polysaccharides on gut microbiota and summarizes the mechanisms involved in targeting gut microbiota for the treatment of intestinal diseases. Further, the structure-activity relationships between different structural types of plant-derived polysaccharides and the occurrence of their prebiotic activity are further explored. Finally, the practical applications of plant-derived polysaccharides in food production and food packaging are summarized and discussed, providing important references for expanding the application of plant-derived polysaccharides in the food industry or developing functional dietary supplements.

Dietary Palygorskite-Based Antibacterial Agent Supplementation as an Alternative to Antibiotics Improves Growth Performance, Blood Parameters, and Rumen Microbiota in Sheep

This research aimed to investigate the effects of a palygorskite-based antibacterial agent (PAA) as an alternative to antibiotics on growth performance, blood parameters, and rumen microbiota in sheep. A total of 120 sheep were randomly divided into five groups of six replicates with four sheep each. Sheep were fed a basal diet, an antibiotic diet supplemented with 500 g/t chlortetracycline (CTC), and a basal diet supplemented with 500, 1000, and 2000 g/t PAA for 80 d, respectively. Supplementation with 2000 g/t PAA and 500 g/t CTC increased the average daily gain (ADG) of sheep compared with the control group (p < 0.05). Diets supplemented with 2000 g/t PAA and 500 g/t CTC reduced (p < 0.05) the feed:gain ratio (F/G ratio) in the overall periods. Dietary supplementation with 1000 g/t PAA significantly increased albumin and total protein (p < 0.05). A significant positive correlation was found between growth hormone concentration and PAA supplementation (p < 0.05). In addition, compared to the control group, the CTC group had higher growth hormone concentration and lower lipopolysaccharide concentration (p < 0.05). No difference was observed between the five groups in terms of rumen fermentation characteristics (p > 0.05). At the phylum level, the relative abundance of Proteobacteria was lower in the PAA 2000 and CTC 500 groups than in the control and PAA 500 groups (p < 0.05). At the genus level, a significant decrease (p < 0.05) in the relative abundance of RuminococcaceaeUCG-010 was observed in the PAA 1000, PAA 2000, and CTC 500 groups compared with that in the control group. In addition, the relative abundance of Prevotella1 (p < 0.05) was higher in the PAA 2000 group than in the control group. These findings indicate that dietary supplementation with PAA has ameliorative effects on growth performance, blood parameters, and rumen microbiota, with an optimal dosage of 2000 g/t for sheep.

Dietary Supplementation of Ancientino Ameliorates Dextran Sodium Sulfate-Induced Colitis by Improving Intestinal Barrier Function and Reducing Inflammation and Oxidative Stress

Ancientino, a complex dietary fiber supplement mimicking the ancient diet, has improved chronic heart failure, kidney function, and constipation. However, its effect on ulcerative colitis is unknown. This study explores the impact of Ancientino on colitis caused by dextran sulfate sodium (DSS) and its mechanisms. Data analyses showed that Ancientino alleviated bodyweight loss, colon shortening and injury, and disease activity index (DAI) score, regulated levels of inflammatory factors (tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10), interleukin-1 beta (IL-1β), and interleukin 6 (IL-6)), reduced intestinal permeability (d-lactate and endotoxin), fluorescein isothiocyanate-dextran (FITC-dextran), and diamine oxidase (DAO), repaired colonic function (ZO-1 and occludin), and suppressed oxidative stress (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA)) in vivo and in vitro. In short, this study demonstrated that Ancientino alleviates colitis and exerts an anticolitis effect by reducing inflammatory response, suppressing oxidative stress, and repairing intestinal barrier function. Thus, Ancientino may be an effective therapeutic dietary resource for ulcerative colitis.

Barley Leaf Ameliorates Citrobacter-rodentium-Induced Colitis through Arginine Enrichment

Inflammatory bowel disease (IBD) has become a global public health challenge. Our previous study showed that barley leaf (BL) significantly reduces Citrobacter-rodentium (CR)-induced colitis, but its mechanism remains elusive. Thus, in this study, we used non-targeted metabolomics techniques to search for potentially effective metabolites. Our results demonstrated that dietary supplementation with BL significantly enriched arginine and that arginine intervention significantly ameliorated CR-induced colitis symptoms such as reduced body weight, shortened colon, wrinkled cecum, and swollen colon wall in mice; in addition, arginine intervention dramatically ameliorated CR-induced histopathological damage to the colon. The gut microbial diversity analysis showed that arginine intervention significantly decreased the relative abundance of CR and significantly increased the relative abundance of Akkermansia, Blautia, Enterorhabdus, and Lachnospiraceae, which modified the CR-induced intestinal flora disorder. Notably, arginine showed a dose-dependent effect on the improvement of colitis caused by CR.

Effects of Alginate Oligosaccharide on Testosterone-Induced Benign Prostatic Hyperplasia in Orchiectomized Rats

Benign prostatic hyperplasia (BPH) is an age-related disease of the urinary system that affects elderly men. Current treatments for BPH are associated with several adverse effects, thus highlighting the need for alternative agents. Alginate oligosaccharide (AOS), a water-soluble functional oligomer derived from brown algae, inhibits prostate cancer cell proliferation. However, the effects of AOS on BPH and the underlying molecular mechanisms remain unclear. Therefore, here, we aimed to investigate the therapeutic potential of AOS in BPH by using human benign prostatic epithelial cells (BPH-1) and a rat model of testosterone-induced BPH. Treatment with AOS inhibited in vitro and in vivo proliferation of prostatic epithelial cells and the testosterone-induced expression of androgen receptor (AR) and androgen-associated genes, such as those encoding 5α-reductase type 2 and prostate-specific antigen. Oral administration of AOS remarkably reduced the serum levels of dihydrotestosterone (DHT) and testosterone as well as the expression of proliferating cell nuclear antigen, inflammatory cytokines, and enzymes, which showed increased levels in prostatic tissues of rats with testosterone-induced BPH. Taken together, these data demonstrate that AOS suppresses testosterone-induced BPH in rats by downregulating AR and the expression of androgen-associated genes, supporting the hypothesis that AOS might be of potential use for the treatment of BPH.

An exploration of alginate oligosaccharides modulating intestinal inflammatory networks via gut microbiota

Alginate oligosaccharides (AOS) can be obtained by acidolysis and enzymatic hydrolysis. The products obtained by different methods have different structures and physiological functions. AOS have received increasing interest because of their many health-promoting properties. AOS have been reported to exert protective roles for intestinal homeostasis by modulating gut microbiota, which is closely associated with intestinal inflammation, gut barrier strength, bacterial infection, tissue injury, and biological activities. However, the roles of AOS in intestinal inflammation network remain not well understood. A review of published reports may help us to establish the linkage that AOS may improve intestinal inflammation network by affecting T helper type 1 (Th1) Th2, Th9, Th17, Th22 and regulatory T (Treg) cells, and their secreted cytokines [the hub genes of protein-protein interaction networks include interleukin-1 beta (IL-1β), IL-2, IL-4, IL-6, IL-10 and tumor necrosis factor alpha (TNF-α)] via the regulation of probiotics. The potential functional roles of molecular mechanisms are explored in this study. However, the exact mechanism for the direct interaction between AOS and probiotics or pathogenic bacteria is not yet fully understood. AOS receptors may be located on the plasma membrane of gut microbiota and will be a key solution to address such an important issue. The present paper provides a better understanding of the protecting functions of AOS on intestinal inflammation and immunity.

Docosapentaenoic Acid (DPA, 22:5n-3) Alleviates Ulcerative Colitis via Modification of Gut Microbiota and Their Metabolism

N-3 polyunsaturated fatty acids (n-3PUFA) are regarded as viable alternatives to aid the treatment of ulcerative colitis (UC). Most research focuses on eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA); little information is available about the effect of docosapentaenoic acid (DPA) on the gut microbiota and their metabolism in UC mice. In this study, the changes in gut microbiota and their metabolism in UC mice were studied through the 16S rRNA sequencing method and untargeted metabolomics. Moreover, the differential bacterial genus and differential metabolites in responding to DPA supplementation were screened through permutation test after orthogonal partial least squares discriminant analysis (OPLS-DA). The results indicated that DPA supplementation increased the diversity and altered the composition of the gut microbiota in UC mice; Akkermansia, Alistipes, Butyricicoccus, and Lactobacillus were selected as the differential bacterial genus. Supplementation of DPA also altered the fecal metabolite profile in the UC mice. Moreover, butyrate, N-carbamylglutamate (NCG), and histamine were screened as the differential metabolites. In conclusion, the regulation effect of DPA on the gut microbiota and their metabolism might be involved in the intervention mechanism of DPA in UC. More research needs to be carried out to elucidate the mechanism systematically.