Effects of inulin-type fructans with different degrees of polymerization on inflammation, oxidative stress and endothelial dysfunction in women with polycystic ovary syndrome: A randomized, double-blind, placebo-controlled trial

OBJECTIVE

Polycystic ovary syndrome (PCOS) is associated with several cardiovascular risk factors. Prebiotics were proposed to beneficially affect risk factors associated with metabolic disorders. The aim of this study was to investigate and compare the effects of inulin-type fructans (ITFs), as well-studied prebiotics, with different degrees of polymerization, on markers of inflammation, oxidative stress and endothelial dysfunction in PCOS patients.

DESIGN

A randomized, double-blind, placebo-controlled trial.

PATIENTS

Seventy-five PCOS women were randomly assigned to receive 10 g/day of either high-performance inulin (HPI) or oligofructose-enriched inulin (OEI) or placebo for 12 weeks.

MEASUREMENTS

Biochemical indices and blood pressure levelswere assessed before and after the intervention.

RESULTS

In the intent-to-treat analysis, high-sensitive C-reactive protein (hs-CRP) decreased in HPI and OEI groups, over the 12 weeks, and the changes were significant in the HPI group, compared to placebo (changes from baseline in the HPI group: -0.11 vs. placebo group: 0.004 mg/L [conversion factor to SI units (nmol/L): 9/5238]; p = .007). Serum levels of nitric oxide (NO) increased, and endothelin-1 and total oxidant status decreased in HPI and OEI groups, at the end of the trial; however, these changes were not significantly compared to placebo (p = .07, .36 and .22, respectively). No differences in systolic and diastolic blood pressure were found. Per-protocol analysis (n = 68) yielded consistent results for all endpoints, with the exception that the significant effect of ITFs on serum hs-CRP levels in the unadjusted ITT analysis became nonsignificant in the per-protocol analysis (p = .06).

CONCLUSION

A 12-week supplementation with long-chain ITFs had favourable effects on inflammatory status among PCOS patients.

Effects of fructooligosaccharides (FOS) on the composition of cecal and fecal microbiota and the quantitative detection of FOS-metabolizing bacteria using species-specific primers

BACKGROUND

Fructooligosaccharides (FOS) are a kind of prebiotic. Previous studies concerning the effect of FOS on intestinal microbiota have focused on Bifidobacterium and Lactobacillus. However, the presence of other FOS-utilizing bacteria makes it necessary to investigate the quantitative changes in these bacterial species in the intestine after FOS intake. In this study, the composition of cecal and fecal microbiota was analyzed using MiSeq sequencing, and the abundance of FOS-utilizing bacteria was detected using quantitative polymerase chain reaction after the oral administration of FOS.

RESULTS

Species-specific primers for FOS-utilizing bacteria were designed with superior amplification efficiency for quantification. After FOS intervention, the relative abundance of Bifidobacterium pseudolongum in feces increased to 17.37% and the abundance reached 2.28 × 10¹⁰  CFU g^-1 . The abundance of Bifidobacterium longum and Bifidobacterium breve did not change significantly. Whereas the abundance of Ligilactobacillus murinus decreased, that of Lactiplantibacillus plantarum, Lacticaseibacillus paracasei, and Lacticaseibacillus rhamnosus remained at approximately 10⁴  CFU g^-1 .

CONCLUSION

Species-specific primers for FOS-utilizing bacteria were successfully developed, and we confirmed that FOS significantly increased the relative abundance and the abundance of B. pseudolongum in mice, while decreasing the proportion of Lactobacillus. The detection of these species using 16S ribosomal DNA sequencing and quantitative polymerase chain reaction showed the same results. Further investigations are needed to reveal the response of the intestinal microbiota to different FOS compositions. These techniques will contribute to future studies about the composition and dynamics of the intestinal microflora. © 2022 Society of Chemical Industry.

Effect of dietary resveratrol supplementation on growth performance, antioxidant capacity, intestinal immunity and gut microbiota in yellow-feathered broilers challenged with lipopolysaccharide

Resveratrol (RES) displays strong antioxidant and anti-inflammatory properties in protecting the animals from various stressors and inflammatory injuries, but its interrelationship with the gut microbiota remained largely unclear. This study was carried out to investigate the effects of dietary RES supplementation on growth performance, antioxidant capacity, intestinal immunity and gut microbiota in yellow-feathered broilers challenged by lipopolysaccharide (LPS). A total of 240 yellow-feathered broilers were randomly assigned to four treatment groups in a 2 × 2 factorial design. The broilers were fed with the control diet or control diet supplemented with 400 mg/kg RES, followed by challenge with LPS or the same amount of saline. Dietary RES supplementation significantly alleviated the decreases in the final body weight (BW), average daily gain (ADG), and ADFI induced by LPS (P < 0.05). LPS challenge significantly increased plasma concentrations of triglyceride, high-density lipoprotein cholesterol (HDL-C), aspartate aminotransferase (AST), and cortisol levels, but decreased triiodothyronine (T3) and insulin levels (P < 0.05). Dietary supplementation with RES significantly reversed the elevated creatinine concentrations and the decreased concentrations of T3 and insulin caused by LPS (P < 0.05). Moreover, dietary RES supplementation significantly increased plasma total antioxidant capacity (T-AOC) and catalase (CAT) activities and superoxide dismutase (SOD) and T-AOC activities in jejunal mucosa and reduced malondialdehyde (MDA) concentration in the plasma (P < 0.05). The reduction in the villus height to crypt depth ratio in duodenum, jejunum and ileum and the shortening of villus height in jejunum and ileum caused by LPS were also alleviated by RES treatment (P < 0.05). Furthermore, the increased concentrations of intestinal tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β caused by LPS were significantly decreased by RES treatment (P < 0.05). Dietary RES treatment increased the mRNA expression of claudin-1, claudin-5, occludin, and zonula occludens-1 (ZO-1), and decreased mRNA expression of IL-1β, IL-8, IL-17, and TNF-α after LPS challenge (P < 0.05). Dietary RES treatments significantly decreased the dominance of cecal microbiota, and increased the Pieiou-e and Simpson index. Moreover, dietary RES supplementation increased relative abundance of UCG_ 009, Erysipelotrichaceae, Christensenellaceae_R-7_group, Anaerotruncus, RF39, and Ruminococcus while decreasing the abundance of Alistipes at genus level. Spearman correlation analysis revealed that the microbes at the order and genus levels significantly correlated with indicators of growth performance, antioxidant capacity, and intestinal health. Collectively, dietary supplementation with 400 mg/kg RES could improve growth performance and antioxidant capacity, and modulate intestinal immunity in yellow-feathered broilers challenged by LPS at early stage, which might be closely associated with the regulation of gut microbiota community composition.

Integrative analysis of gut microbiota and fecal metabolites in metabolic associated fatty liver disease patients

Objective

Metabolic associated fatty liver disease (MAFLD) affects nearly a quarter of the world’s population. Our study aimed to characterize the gut microbiome and overall changes in the fecal and serum metabolomes in MAFLD patients.

Methods

Thirty-two patients diagnosed with MAFLD and 30 healthy individuals (control group, CG) were included in this study, the basic clinical characteristics and laboratory test results including routine biochemistry, etc. were recorded for all, and their serum and fecal samples were collected. A portion of the fecal samples was subjected to 16S rDNA sequencing, and the other portion of the fecal samples and serum samples were subjected to non-targeted metabolomic detection based on liquid chromatography-mass spectrometry (LC–MS). Statistical analysis of clinical data was performed using SPSS software package version 25.0 (SPSS Inc., Chicago, IL, United States). The analysis of 16S rDNA sequencing results was mainly performed by R software (V. 2.15.3), and the metabolomics data analysis was mainly performed by CD 3.1 software. Two-tailed p value < 0.05 was considered statistically significant.

Results

The 16S sequencing data suggested that the species richness and diversity of MAFLD patients were reduced compared with controls. At the phylum level, the relative abundance of Bacteroidota, Pseudomonadota, and Fusobacteriota increased and Bacillota decreased in MAFLD patients. At the genus level, the relative abundances of Prevotella, Bacteroides, Escherichia-Shigella, etc. increased. 2,770 metabolites were detected in stool samples and 1,245 metabolites were detected in serum samples. The proportion of differential lipid metabolites in serum (49%) was higher than that in feces (21%). There were 22 differential metabolites shared in feces and serum. And the association analysis indicated that LPC 18:0 was positively correlated with Christensenellaceae_R-7_group, Oscillospiraceae_UCG-002; neohesperidin was also positively correlated with Peptoniphilus, Phycicoccus, and Stomatobaculum.

Conclusion

Microbial sequencing data suggested decreased species richness and diversity and altered β-diversity in feces. Metabolomic analysis identified overall changes in fecal and serum metabolites dominated by lipid molecules. And the association analysis with gut microbes provided potentially pivotal gut microbiota-metabolite combinations in MAFLD patients, which might provide new clues for further research on the disease mechanism and the development of new diagnostic markers and treatments.

Cranberry polyphenols and agave agavins impact gut immune response and microbiota composition while improving gut barrier function, inflammation, and glucose metabolism in mice fed an obesogenic diet

The consumption of plant-based bioactive compounds modulates the gut microbiota and interacts with the innate and adaptive immune responses associated with metabolic disorders. The present study aimed to evaluate the effect of cranberry polyphenols (CP), rich in flavonoids, and agavins (AG), a highly branched agave-derived neo-fructans, on cardiometabolic response, gut microbiota composition, metabolic endotoxemia, and mucosal immunomodulation of C57BL6 male mice fed an obesogenic high-fat and high-sucrose (HFHS) diet for 9 weeks. Interestingly, CP+AG-fed mice had improved glucose homeostasis. Oral supplementation with CP selectively and robustly (five-fold) increases the relative abundance of Akkermansia muciniphila, a beneficial bacteria associated with metabolic health. AG, either alone or combined with CP (CP+AG), mainly stimulated the glycan-degrading bacteria Muribaculum intestinale, Faecalibaculum rodentium, Bacteroides uniformis, and Bacteroides acidifaciens. This increase of glycan-degrading bacteria was consistent with a significantly increased level of butyrate in obese mice receiving AG, as compared to untreated counterparts. CP+AG-supplemented HFHS-fed mice had significantly lower levels of plasma LBP than HFHS-fed controls, suggesting blunted metabolic endotoxemia and improved intestinal barrier function. Gut microbiota and derived metabolites interact with the immunological factors to improve intestinal epithelium barrier function. Oral administration of CP and AG to obese mice contributed to dampen the pro-inflammatory immune response through different signaling pathways. CP and AG, alone or combined, increased toll-like receptor (TLR)-2 (Tlr2) expression, while decreasing the expression of interleukin 1ß (ILß1) in obese mice. Moreover, AG selectively promoted the anti-inflammatory marker Foxp3, while CP increased the expression of NOD-like receptor family pyrin domain containing 6 (Nlrp6) inflammasome. The intestinal immune system was also shaped by dietary factor recognition. Indeed, the combination of CP+AG significantly increased the expression of aryl hydrocarbon receptors (Ahr). Altogether, both CP and AG can shape gut microbiota composition and regulate key mucosal markers involved in the repair of epithelial barrier integrity, thereby attenuating obesity-associated gut dysbiosis and metabolic inflammation and improving glucose homeostasis.

Effects of dietary supplementation with multispecies probiotics on intestinal epithelial development and growth performance of neonatal calves challenged with Escherichia coli K99

BACKGROUND

Probiotics exhibit antibiotic properties and are capable of treating certain bacterial infections, including diarrhea. Therefore, the aim of this study is to investigate the effects of dietary supplementation with multispecies probiotic (MSP) on diarrhea, average daily gain (ADG) and intestinal development of neonatal calves challenged with Escherichia coli K99.

RESULTS

Thirty-six neonatal Holstein calves were randomly assigned to three treatment groups. After E. coli K99 challenge, calves in the control (C) and MSP treatment groups had significantly higher ADG and feed efficiency, and significantly lower fecal scores than those of calves in the diarrhea (D) group. The mean time of diarrhea resolution was 4.5 and 3.1 days for calves in the D and MSP treatment groups, respectively. Furthermore, the structures of the various segments (duodenum, jejunum and ileum) of the small intestine of the calves, activities of several small intestinal enzymes, and expression of several energy metabolism-related genes in the small intestine segments were significantly affected by MSP treatments.

CONCLUSION

Dietary supplementation of MSP had a positive effect in treating calf diarrhea; it improved ADG and feed efficiency and promoted development of the small intestine. © 2022 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Traditional Chinese Medicine Formula Jian Pi Tiao Gan Yin Reduces Obesity in Mice by Modulating the Gut Microbiota and Fecal Metabolism

The current study employed the high-fat diet (HFD) induced murine model to assess the relationship between the effect of Jian Pi Tiao Gan Yin (JPTGY) and the alterations of gut microbiota and fecal metabolism. C57BL/6 mice were used to establish an animal model of obesity via HFD induce. Serum biochemical indicators of lipid metabolism were used to evaluate the pharmacodynamics of JPTGY in obese mice. Bacterial communities and metabolites in the feces specimens from the controls, the Group HFD, and the JPTGY-exposed corpulency group were studied by 16s rDNA genetic sequence in combination with liquid chromatography-mass spectrometry (LC-MS) based untargeted fecal metabolomics techniques. Results revealed that JPTGY significantly decreased the levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and elevated high-density lipoprotein cholesterol (HDL-C). Moreover, JPTGY could up-regulate the abundance and diversity of fecal microbiota, which was characterized by the higher phylum of proteobacteria. Consistently, at the genus levels, JPTGY supplementation induced enrichments in Lachnospiraceae NK4A136 group, Oscillibacter, Turicibacter, Clostridium sensu stricto 1, and Intestinimonas, which were intimately related to 14 pivotal fecal metabolins in respond to JPTGY therapy were determined. What is more, metabolomics further analyses show that the therapeutic effect of JPTGY for obesity involves linoleic acid (LA) metabolism paths, alpha-linolenic acid (ALA) metabolism paths, glycerophospholipid metabolism paths, arachidonic acid (AA) metabolism paths, and pyrimidine metabolism paths, which implied the potential mechanism of JPTGY in treating obesity. It was concluded that the linking of corpulency phenotypes with intestinal flora and fecal metabolins unveils the latent causal link of JPTGY in the treatment of hyperlipidemia and obesity.

Dietary Inulin Supplementation Affects Specific Plasmalogen Species in the Brain

Plasmalogens (Pls) are glycerophospholipids that play critical roles in the brain. Evidence supports the role of diet and that of the gut microbiota in regulating brain lipids. We investigated the impact of dietary intake of inulin—a soluble fiber used as prebiotic—on the Pl content of the cortex in mice. No global modification in the Pl amounts was observed when evaluated by gas chromatographic analysis of dimethyl acetals (DMAs). However, the analysis of individual molecular species of Pls by liquid chromatography revealed a reduced abundance of major species of ethanolamine Pls (PlsEtn)―PE(P-18:0/22:6) and PE(P-34:1)―in the cortex of mice fed a diet supplemented with inulin. DMA and expression levels of genes (Far-1, Gnpat, Agps, Pla2g6 and Tmem86b) encoding key enzymes of Pl biosynthesis or degradation were not altered in the liver and in the cortex of mice exposed to inulin. In addition, the fatty acid profile and the amount of lyso forms derived from PlsEtn were not modified in the cortex by inulin consumption. To conclude, inulin affects the brain levels of major PlsEtn and further investigation is needed to determine the exact molecular mechanisms involved.

Microscale thermophoresis as a powerful growing analytical technique for the investigation of biomolecular interaction and the determination of binding parameters

The in vitro panel of technologies to address biomolecular interactions are in play, however microscale thermophoresis is continuously increasing in use to represent a key player in this arena. This review highlights the usefulness of microscale thermophoresis in the determination of molecular and biomolecular affinity interactions. This work reviews the literature from January 2016 to January 2022 about microscale thermophoresis. It gives a summarized overview about both the state-of the art and the development in the field of microscale thermophoresis. The principle of microscale thermophoresis is also described supported with self-created illustrations. Moreover, some recent advances are mentioned that showing application of the technique in investigating biomolecular interactions in different fields. Finally, advantages as well as drawbacks of the technique in comparison with other competing techniques are summarized.

Coix Seed-Based Milk Fermented With Limosilactobacillus reuteri Improves Lipid Metabolism and Gut Microbiota in Mice Fed With a High-Fat Diet

The aim of this study was to investigate the effects of coix seed-based milk (CSM) fermented with Limosilactobacillus reuteri (L. reuteri) on dyslipidemia and the composition of the intestinal microbiota in high fat diet (HFD)-fed mice. Changes in the body weight, serum lipid levels, activities of hepatic oxidative stress factors, expression of lipid-related genes, and composition of the intestinal microbiota of HFD-fed mice after supplementation with CSM were determined. The results showed that intake of CSM reduced the body weight gain as well as serum total cholesterol (TC), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) levels, and increased the high-density lipoprotein cholesterol (HDL-C) levels in the mice. Meanwhile, supplementation with CSM could relieve liver oxidative stress, down-regulate the expression of genes related to lipid synthesis, and prevent liver fat accumulation in mice fed with HFD. The 16S rRNA sequencing of the intestinal microbiota showed that CSM regulated the gut microbiota community structure at different taxonomic levels, and reversed gut dysbiosis induced by HFD. The relative abundance of Muribaculaceae, Lachnospiraceae, Dubosiella and Akkermansia which are negatively correlated with blood lipid levels were significantly increased by the intervention of CSM, while the relative abundance of Desulfovibrionaceae, Ruminococca-ceae_UCG-014, Psychrobacter, and Staphylococcus which have positive correlation with blood lipid levels were significantly decreased. These results indicated that CSM might serve as a novel and promising dietary supplement for ameliorating hyperlipidemia and intestinal microbiota disorders caused by HFDs.

Neuroprotective, Anti-inflammatory Effect of Furanochrome, Visnagin Against Middle Cerebral Ischemia-Induced Rat Model

In recent years, the medical field had significantly progressed to a greater extent which was evidenced with increased life expectancy and decreased mortality rate. Due to the growth of medical field, numerous communicable diseases are prevented and eradicated, whereas the non-communicable disease incidence has been increased globally. One such non-communicable disease which threatens the global population is stroke. Stroke tends to be the second leading cause of death and disability in older population. In lower- and middle-income countries, increased incidence rate of stroke was also evidenced in younger population which is alarming. Lifestyle changes, poor physical activity, stress, consumption of alcohol, oral contraception, and smoking tend to be the causative agents of stroke. Since thrombus formation is the major pathology of stroke, drugs were targeted to thrombolysis. Currently thrombolytic, antiplatelet, and anticoagulant therapies were given for the stroke patients. But the recovery rate of stroke patients with available drugs is very slow. Hence, it is a need of today to discover a drug with increased recovery rate and decreased or nil side effects. Phytochemicals are the best options to treat such non-communicable chronic diseases. Visnagin is one such compound which is used to regulate blood pressure, treat kidney stones, tumors of bile duct, renal colic, and whooping cough. It possesses anti-inflammatory, neuroprotective, and cardioprotective properties; it was also proven to treat epileptic seizures. In this study, the anti-ischemic effect of a furanochrome visnagin was assessed in in vivo rat model. Middle cerebral ischemic/reperfusion was induced in healthy male Sprague Dawley rats and treated with different concentrations of visnagin. The neuroprotective effect of visnagin against cerebral ischemia-induced rats was assessed by analyzing the neurological score, brain edema, infract volume, and Evans blue leakage. The anti-inflammatory property of visnagin was assessed by quantifying proinflammatory cytokines in serum and brain tissues of cerebral ischemia-induced rats. Prostaglandin E-2, COX-2, and NFκ-β were estimated to assess the anti-ischemic effect of visnagin. Histopathological analysis with H&E staining was performed to confirm the neuroprotective effect of visnagin against cerebral ischemia. Our results authentically confirm that visnagin has prevented the inflammation in brain region of cerebral ischemia-induced rats. The neurological scoring and the quantification of PGE-2, COX-2, and NFκ-β prove the anti-ischemic effect of visnagin. Furthermore, the histopathological analysis of hippocampal region provides evidence to the neuroprotective effect of visnagin against cerebral ischemia. Overall, our study confirms visnagin as a potent alternative drug to treat stroke.

Restoration of cefixime-induced gut microbiota changes by a prebiotic blend in a mouse model

Recent studies have provided compelling evidence linking the composition of the gut microbiota, host diet, and host physiology. Prebiotics are substrates that are selectively utilized by host microorganisms, conferring health benefits. Prebiotics, such as prebiotic blends (PB), are commonly used worldwide in food processing. Here, microbiome-metabolomics was used to evaluate how PB affect gut microbes and metabolic functions in C57BL/6 J mice administered cefixime. We found favorable effects of PB on obesity outcomes. PB supplementation significantly increased the abundance of Bifidobacterium, Parabacteroides, Alloprevotella, Alistipes, and Dubosiella, and decreased that of Robinsoniella, Blautia, Lachnoclostridium, Coprobacillus, Hungatella, Erysipelatoclostridium, Helicobacter, Clostridium sensu stricto 1, Enterococcus, and Akkermansia compared to that in the cefixime administration (CEF) group. In particular, PB increased the abundance of Parabacteroides goldsteinii and suppressed that of Robinsoniella peoriensis and Akkermansia muciniphila. In addition, it regulated the levels of microbial metabolites such as unsaturated fatty acids and bile acids. Thus, PB can alleviate metabolic disorders induced by antibiotic intervention, indicating a potential dietary strategy for populations with antibiotic-associated diarrhea. KEY POINTS: • Prebiotic blends significantly increased the Parabacteroides goldsteinii colony. • Prebiotic blends selectivity reversed this increase of Akkermansia muciniphila by antibiotic intervention. • Prebiotic blends relieve cefixime-induced alteration of intestinal flora by regulating metabolites, such as fatty acids and bile acids.

Elucidating the Role of Innate and Adaptive Immune Responses in the Pathogenesis of Canine Chronic Inflammatory Enteropathy-A Search for Potential Biomarkers

Simple Summary

Canine chronic inflammatory enteropathy (CIE) is a chronic disease affecting the small or large intestine and, in some cases, the stomach of dogs. This gastrointestinal disorder is common and is characterized by recurrent vomiting, diarrhea, and weight loss in affected dogs. The pathogenesis of IBD is not completely understood. Similar to human IBD, potential disease factors include genetics, environmental exposures, and dysregulation of the microbiota and the immune response. Some important components of the innate and adaptive immune response involved in CIE pathogenesis have been described. However, the immunopathogenesis of the disease has not been fully elucidated. In this review, we summarized the literature associated with the different cell types and molecules involved in the immunopathogenesis of CIE, with the aim of advancing the search for biomarkers with possible diagnostic, prognostic, or therapeutic utility.

Abstract

Canine chronic inflammatory enteropathy (CIE) is one of the most common chronic gastrointestinal diseases affecting dogs worldwide. Genetic and environmental factors, as well as intestinal microbiota and dysregulated host immune responses, participate in this multifactorial disease. Despite advances explaining the immunological and molecular mechanisms involved in CIE development, the exact pathogenesis is still unknown. This review compiles the latest reports and advances that describe the main molecular and cellular mechanisms of both the innate and adaptive immune responses involved in canine CIE pathogenesis. Future studies should focus research on the characterization of the immunopathogenesis of canine CIE in order to advance the establishment of biomarkers and molecular targets of diagnostic, prognostic, or therapeutic utility.

Recent Discoveries on Marine Organism Immunomodulatory Activities

Marine organisms have been shown to be a valuable source for biologically active compounds for the prevention and treatment of cancer, inflammation, immune system diseases, and other pathologies. The advantage of studying organisms collected in the marine environment lies in their great biodiversity and in the variety of chemical structures of marine natural products. Various studies have focused on marine organism compounds with potential pharmaceutical applications, for instance, as immunomodulators, to treat cancer and immune-mediated diseases. Modulation of the immune system is defined as any change in the immune response that can result in the induction, expression, amplification, or inhibition of any phase of the immune response. Studies very often focus on the effects of marine-derived compounds on macrophages, as well as lymphocytes, by analyzing the release of mediators (cytokines) by using the immunological assay enzyme-linked immunosorbent assay (ELISA), Western blot, immunofluorescence, and real-time PCR. The main sources are fungi, bacteria, microalgae, macroalgae, sponges, mollusks, corals, and fishes. This review is focused on the marine-derived molecules discovered in the last three years as potential immunomodulatory drugs.

Fructan oligosaccharide priming alters apoplastic sugar dynamics and improves resistance against Botrytis cinerea in chicory

Carbohydrates such as fructans can be involved in priming or defence stimulation, and hence potentially provide new strategies for crop protection against biotic stress. Chicory (Cichorium intybus) is a model plant for fructan research and is a crop with many known health benefits. Using the chicory-Botrytis cinerea pathosystem, we tested the effectiveness of fructan-induced immunity, focussing on different plant and microbial fructans. Sugar dynamics were followed after priming and subsequent pathogen infection. Our results indicated that many higher plants might detect extracellular levan oligosaccharides (LOS) of microbial origin, while chicory also detects extracellular small inulin-type fructooligosaccharides (FOS) of endogenous origin, thus differing from the findings of previous fructan priming studies. No clear positive effects were observed for inulin or mixed-type fructans. An elicitor-specific burst of reactive oxygen species was observed for sulfated LOS, while FOS and LOS both behaved as genuine priming agents. In addition, a direct antifungal effect was observed for sulfated LOS. Intriguingly, LOS priming led to a temporary increase in apoplastic sugar concentrations, mainly glucose, which could trigger downstream responses. Total sugar and starch contents in total extracts of LOS-primed leaves were higher after leaf detachment, indicating they could maintain their metabolic activity. Our results indicate the importance of balancing intra- and extracellular sugar levels (osmotic balance) in the context of 'sweet immunity' pathways.

Deciphering the Interdependent Labyrinth between Gut Microbiota and the Immune System

The human gut microbiome interacts with each other and the host, which has significant effects on health and disease development. Intestinal homeostasis and inflammation are maintained by the dynamic interactions between gut microbiota and the innate and adaptive immune systems. Numerous metabolic products produced by the gut microbiota play a role in mediating cross-talk between gut epithelial and immune cells. In the event of an imbalance between the immune system and microbiota, the body becomes susceptible to infections, and homeostasis is compromised. This review mainly focuses on the interplay between microbes and the immune system, such as, T-cell and B-cell mediated adaptive responses to microbiota and signaling pathways for effective communication between the two. We have also highlighted the role of microbes in the activation of the immune response, the development of memory cells, and how the immune system determines the diversity of human gut microbiota. The review also explains the relationship of commensal microbiota and their relation in the production of immunoglobulins.

Ferulic acid improves intestinal barrier function through altering gut microbiota composition in high-fat diet-induced mice

PURPOSE

A high-fat diet (HFD) induces gut microbiota (GM) disorders, leading to intestinal barrier dysfunction and inflammation. Ferulic acid (FA) has shown anti-obesity effects, e.g., reducing body weight and food intake. However, the mechanism linking the anti-obesity effects of FA and GM modulation remains obscure. The present study aimed to clarify the mechanism underlying the anti-obesity effects of FA and modulation of the GM.

METHODS

C57BL/6 J mice were fed by a low-fat diet (LFD) and HFD with or without FA at a dose of 100 mg/kg of body weight by oral gavage for 12 weeks. Using high-throughput sequencing, gas chromatography, real-time fluorescence quantitative PCR and immunohistochemical staining, the attenuation of obesity by FA were assessed via intestinal barrier integrity, inflammation, and the GM.

RESULTS

FA reduced weight gain, improved HFD-induced GM imbalance, significantly enhanced intestinal short-chain fatty acid (SCFA)-producing bacteria (e.g., Olsenella, Eisenbergiella, Dubosiella, Clostridiales_unclassified, and Faecalibaculum) along with SCFA accumulation and its receptors' expression, decreased endotoxin-producing bacteria or obesity-related bacterial genera, and serum endotoxin (lipopolysaccharides), and inhibited the colonic TLR4/NF-κB pathway. Thus, FA can mitigate colonic barrier dysfunction and intestinal inflammation, induce the production of SCFAs and inhibit endotoxins by modulating the GM.

CONCLUSION

These results indicate that enhancement of intestinal barrier by altering the GM may be an anti-obesity target of FA and that FA can be used as a functional compound with great developmental values.

Effect of daily co-exposure to inulin and chlorpyrifos on selected microbiota endpoints in the SHIME® model

The intestinal microbiota has a key role in human health via the interaction with the somatic and immune cells in the digestive tract environment. Food, through matrix effect, nutrient and non-nutrient molecules, is a key regulator of microbiota diversity. As a food contaminant, the pesticide chlorpyrifos (CPF) has an effect on the composition of the intestinal microbiota and induces perturbation of microbiota. Prebiotics (and notably inulin) are known for their ability to promote an equilibrium of the microbiota that favours saccharolytic bacteria. The SHIME® dynamic in vitro model of the human intestine was exposed to CPF and inulin concomitantly for 30 days, in order to assess variations in both the bacterial populations and their metabolites. Various analyses of the microbiota (notably temporal temperature gradient gel electrophoresis) revealed a protective effect of the prebiotic through inhibition of the enterobacterial (E. coli) population. Bifidobacteria were only temporarily inhibited at D15 and recovered at D30. Although other potentially beneficial populations (lactobacilli) were not greatly modified, their activity and that of the saccharolytic bacteria in general were highlighted by an increase in levels of short-chain fatty acids and more specifically butyrate. Given the known role of host-microbiota communication, CPF's impact on the body's homeostasis remains to be determined.

High molecular weight chitosan oligosaccharide exhibited antifungal activity by misleading cell wall organization via targeting PHR transglucosidases

The fungal cell wall is an ideal target for the design of antifungal drugs. In this study we used an analog of cell wall polymer, a highly deacetylated high molecular-weight chitosan oligosaccharide (HCOS), to test its effect against pathogenic Candida strains. Results showed that HCOS was successfully incorporated into the dynamic cell wall organization process and exhibited an apparent antifungal activity against both plankton and mature fungal biofilm, by impairing the cell wall integrity. Unexpectedly, mechanistic studies suggested that HCOS exerts its activity by interfering with family members of PHR β-(1,3)-glucanosyl transferases and affecting the connection and assembly of cell wall polysaccharides. Furthermore, HCOS showed great synergistic activity with different fungicides against Candida cells, especially those in biofilm. These findings indicated HCOS has a great potential as an antifungal drug or drug synergist and proposed a novel antifungal strategy with structure-specific oligosaccharides mimicking cell wall polysaccharide fragments.

Liver alterations are not improved by inulin supplementation in alcohol use disorder patients during alcohol withdrawal: A pilot randomized, double-blind, placebo-controlled study

Background

Emerging evidence highlights that targeting the gut microbiota could be an interesting approach to improve alcohol liver disease due to its important plasticity. This study aimed to evaluate the effects of inulin supplementation on liver parameters in alcohol use disorder (AUD) patients (whole sample) and in a subpopulation with early alcohol-associated liver disease (eALD).

Methods

Fifty AUD patients, hospitalized for a 3-week detoxification program, were enrolled in a randomized, double-blind, placebo-controlled study and assigned to prebiotic (inulin) versus placebo for 17 days. Liver damage, microbial translocation, inflammatory markers and 16S rDNA sequencing were measured at the beginning (T1) and at the end of the study (T2).

Findings

Compared to placebo, AST (β = 8.55, 95% CI [2.33:14.77]), ALT (β = 6.01, 95% CI [2.02:10.00]) and IL-18 (β = 113.86, 95% CI [23.02:204.71]) were statistically significantly higher in the inulin group in the whole sample at T2. In the eALD subgroup, inulin supplementation leads to specific changes in the gut microbiota, including an increase in Bifidobacterium and a decrease of Bacteroides. Despite those changes, AST (β = 14.63, 95% CI [0.91:28.35]) and ALT (β = 10.40, 95% CI [1.93:18.88]) at T2 were higher in the inulin group compared to placebo. Treatment was well tolerated without important adverse events or side effects.

Interpretation

This pilot study shows that 17 days of inulin supplementation versus placebo, even though it induces specific changes in the gut microbiota, did not alleviate liver damage in AUD patients. Further studies with a larger sample size and duration of supplementation with adequate monitoring of liver parameters are needed to confirm these results. Gut2Brain study: https://clinicaltrials.gov/ct2/show/NCT03803709

Funding

Fédération Wallonie-Bruxelles, FRS-FNRS, Fondation Saint-Luc.

Inulin fructans in diet: Role in gut homeostasis, immunity, health outcomes and potential therapeutics

Inulin consumption in both humans and animal models is recognized for its prebiotic action with the most consistent change that lies in enhancing the growth and functionality of Bifidobacterium bacteria, as well as its effect on host gene expression and metabolism. Further, inulin-type fructans are utilized in the colon by bacterial fermentation to yield short-chain fatty acids (SCFAs), which play important role in its biological effects both locally inside the gut and in systemic actions. The gut symbiosis sustained by inulin supplementation among other dietary fibers exerts preventive and/or therapeutic options for many metabolic disorders including obesity, type 2 diabetes mellitus, cardiometabolic diseases, kidney diseases and hyperuricemia. Although, gastrointestinal negative effects due to inulin consumption were reported, such as gastrointestinal symptoms in humans and exacerbated inflammatory bowel disease (IBD) in mice. This comprehensive review aims to present the whole story of how inulin functions as a prebiotic at cellular levels and the interplay between physiological, functional and immunological responses inside the animal or human gut as influenced by inulin in diets, in context to its structural composition. Such review is of importance to identify management and feed strategies to optimize gut health, for instance, consumption of the tolerated doses to healthy adults of 10 g/day of native inulin or 5 g/day of naturally inulin-rich chicory extract. In addition, inulin-drug interactions should be further clarified particularly if used as a supplement for the treatment of degenerative diseases (e.g., diabetes) over a long period. The combined effect of probiotics and inulin appears more effective, and more research on this synergy is still needed.

Phlorizin alleviates cholinergic memory impairment and regulates gut microbiota in d-galactose induced mice

We explored the effect of phlorizin against cholinergic memory impairment and dysbacteriosis in D-galactose induced ICR mice. The control (CON) group, D-galactose model (DGM) group, and three groups (DG-PL, DG-PM, DG-PH) treated with phlorizin at 0.01%, 0.02%, and 0.04% (w/w) in diets were raised for 12 weeks. Supplementing with phlorizin reversed the loss of organ coefficient and body weight caused by D-galactose. The functional abilities of phlorizin on hippocampal-dependent spatial learning and memory, anti-oxidation, anti-inflammation were also observed. Meanwhile, phlorizin intervention upregulated the gene expression of Nrf2, GSH-PX, SOD1, decreased the gene expression of NF-κB, TLR-4, TNF-α, and IL-1β in the hippocampus, while enhanced the gene expression of JAM-A, Mucin2, Occludin in the caecum. Furthermore, a neurotransmitter of acetylcholine (ACh) was enhanced, while acetylcholinesterase (AChE) activity was inhibited by phlorizin administration. Moreover, phlorizin administration increased short-chain fatty acids (SCFAs) content, and reduced lipopolysaccharides (LPS) levels, which may relate to the rebuilding of gut microbiota homeostasis. Treatment with phlorizin may be an effective intervention for alleviating cognitive decline and gut microbiota dysbiosis.

Chitosan oligosaccharides exert neuroprotective effects via modulating the PI3K/Akt/Bcl-2 pathway in a Parkinsonian model

Parkinson's disease (PD), the second most common neurodegenerative disease, is a threat to patients due to the inability to prevent or decelerate disease progression. Currently, most clinical drugs for the treatment of PD are synthetic drugs that always present undesirable adverse or toxic effects. Chitosan oligosaccharide (COS) is a natural oligosaccharide that has been considered relatively safe and studied in the therapeutic effects on different types of neuronal disorders. In this study, we separated four COS monomers (COSs) including chitobiose (COS2), chitotriose (COS3), chitotetraose (COS4) and chitopentaose (COS5) to explore their structure-activity relationship in PD mice induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Techniques including TLC, HPLC, MS, and NMR were applied to investigate the purity and structure of the COSs. After the oral administration of COSs, behavior indexes, pathological indexes, cytokines, and expression of proteins in the nigrostriatal pathway of the mice were analyzed. The results showed that the four COSs were fully deacetylated and the purity was >90%. Additionally, the neurobehavioral deficits of the PD mice were improved by treatment with COSs. The results further proved that COSs could protect the TH-labelled dopaminergic neurons via reducing the overexpression of α-synuclein, alleviating neuroinflammation, and activating the PI3K/Akt/Bcl-2 pathway to reduce apoptosis. COS3 exhibited a better effect on protecting dopaminergic neurons; however, COS2 provided a better effect on reducing the overexpression of α-synuclein. To conclude, the neuroprotective activity makes COSs a viable candidate as an ingredient for healthcare products.

Lactoferrin modulates gut microbiota and Toll-like receptors (TLRs) in mice with dysbiosis induced by antibiotics

Background: Antibiotic administration can result in gut microbiota and immune system alterations that impact health. Bovine lactoferrin is a milk protein with anticancer, anti-inflammatory, antimicrobial and immune modulatory activities. The aim was to study the ability of native and iron-saturated lactoferrin to reverse the effects of clindamycin on gut microbiota and intestinal Toll-like receptor (TLR) expression in a murine model. Methods: Male C57BL/6 mice were treated with vehicle, clindamycin (Clin), native bovine lactoferrin (nLf), nLf + clindamycin (nLf_Clin), iron-saturated bovine lactoferrin (sLf) and sLf + clindamycin (sLf_Clin). Fecal samples of each group were collected, and bacterial DNA was extracted. Sequencing of 16s rRNA V4 hypervariable gene regions was conducted to assess the microbial composition. mRNA expression levels of TLRs (1-9) were determined in mouse colon by qPCR. Pearson's correlation test was carried out between bacteria showing differences in abundance among samples and TLR2, TLR8 and TLR9. Results: Beta-diversity analysis showed that the microbial community of the vehicle was different from the communities of Clin, nLf_Clin and sLf_Clin. At the family level, Bacteroidaceae, Prevotellaceae and Rikenellaceae decreased in the Clin group, and treatment with nLf or sLf reverted these effects. Clin reduced the expression of TLR2, TLR8 and TLR9 and sLf reverted the decrease in the expression of these receptors. Finally, TLR8 was positively correlated with Rikenellaceae abundance. Conclusion: In a situation of intestinal dysbiosis induced by clindamycin, lactoferrin restores the normal levels of some anti-inflammatory bacteria and TLRs and, therefore, could be a good ingredient to be added to functional foods.

Food as Treatment of Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD), namely, Crohn's disease (CD) and ulcerative colitis (UC), are lifelong and incurable chronic inflammatory diseases affecting 6.8 million people worldwide. By 2030, the prevalence of IBD is estimated to reach 1% of the population in Western countries, and thus there is an urgent need to develop effective therapies to reduce the burden of this disease. Microbiome dysbiosis is at the heart of the IBD pathophysiology, and current research and development efforts for IBD treatments have been focused on gut microbiome regulation. Diet can shape the intestinal microbiome. Diet is also preferred over medication, is safe, and has been proven to be an effective strategy for the management of IBD. Therefore, although often overlooked, dietary interventions targeting the microbiome represent ideal treatments for IBD. Here, I summarize the latest research on diet as a treatment for IBD from infancy to adulthood, compile evidence of the mechanisms of action behind diet as treatment, and, lastly, provide insights into future research focusing on culturally tailored diets for ethnic minority groups with increased incidence of IBD yet underrepresented in nutrition research.

Modulating the Growth, Antioxidant Activity, and Immunoexpression of Proinflammatory Cytokines and Apoptotic Proteins in Broiler Chickens by Adding Dietary Spirulina platensis Phycocyanin

This study investigated the dietary effect of Spirulina platensis phycocyanin (SPC) on growth performance (body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR)) at starter, grower, and finisher stages, intestinal histomorphology, serum biochemical parameters, inflammatory and antioxidant indices, and proinflammatory cytokines (tumor necrosis factor-α and caspase-3) immune expression in broiler chickens. In total, 250 one-day-old chicks (Ross 308 broiler) were randomly allotted to five experimental groups (5 replicates/group, 10 chicks/replicate) and fed basal diets supplemented with five levels of SPC (0, 0.25, 0.5, 0.75, and 1 g kg–1 diet) for 35 days. Compared with SPC0 treatment, different SPC levels increased the overall BW and BWG without affecting the total feed consumption. However, the FCR decreased linearly with an increase in supplementation level. The serum levels of total proteins, albumin, globulins, and growth hormone increased linearly by increasing levels of SPC supplementation. Further, SPC supplementation increased the thyroxin hormones without affecting serum glucose and leptin levels. Serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) values decreased in broilers fed SPC0.250 and SPC1 diets. Triglycerides (TG) decreased in SPC0.25-, SPC0.75-, and SPC1-treated groups. Though antioxidant enzyme activities (total antioxidant capacity, catalase, and superoxide dismutase) increased linearly and quadratically, malondialdehyde (MDA) decreased linearly by increasing the SPC level. There was no effect on serum proinflammatory cytokines IL1β levels. Immunolabelling index of caspase-3 and tumor necrosis factor-α (TNF-α) were downregulated by SPC supplementation. The intestinal histomorphology is represented by increased villus height, the villus height to crypt depth ratio, and numbers of goblet cells in different sections of the small intestine. In conclusion, SPC supplementation is beneficial in broiler chicken diets due to its growth-promoting, antioxidant, and anti-inflammatory properties.

Dietary Eggshell Membrane Powder Improves Survival Rate and Ameliorates Gut Dysbiosis in Interleukin-10 Knockout Mice

Inflammatory bowel disease (IBD) is known to be associated with compositional and metabolic changes in the gut microbiota. The aim of this study was to investigate whether dietary eggshell membrane (ESM) improves survival rate or ameliorates gut dysbiosis in a spontaneous IBD model of interleukin-10 knockout (IL10^−/−) mice. Female C57BL/6J wild-type (WT) and IL10^−/− mice (KO) were fed an AIN-93G basal diet or an ESM diet (KOE) for 19 weeks. Gut microbiota profiles were analyzed via 16S rRNA sequencing, and short-chain fatty acids in cecal content were analyzed with high-performance liquid chromatography. The results demonstrated that ESM supplementation significantly improved the survival rate and body composition in KO mice. Alpha diversity analysis of the microbiota revealed that ESM supplementation significantly increased gut microbial diversity, which was decreased in IL10^−/− mice. The Firmicutes/Bacteroidetes ratio was recovered to a normal level by ESM supplementation, suggesting that ESM helps maintain the compositional balance of the gut microbiota. ESM increased relative abundance of commensal bacterial Ruminococcus and Bacteroidales S24-7 and reduced the abundance of the proinflammatory-related bacterium, Enterobacteriaceae. Additionally, ESM supplementation promoted the production of butyrate in cecal contents and downregulated the expression of proinflammatory genes, including interleukin-1β (Il-1β) and tumor necrosis factor-α (Tnf-α) in IL10^−/− mice colon, indicating anti-inflammatory functions. These findings suggest that ESM may be used as a beneficial dietary intervention for IBD.

Butyric Acid Ameliorates Myocardial Fibrosis by Regulating M1/M2 Polarization of Macrophages and Promoting Recovery of Mitochondrial Function

Background

We aimed to investigate the effect and mechanism of butyric acid on rat myocardial fibrosis (MF).

Methods

16S rRNA sequencing was used to analyze the gut microbiota characteristics of the Sham group and MF group. HPLC was applied to measure butyric acid in the feces and serum. In vitro, rat macrophages RMa-bm were stimulated with LPS and IL-4, respectively, and then butyrate was added to study the influences of butyrate on M1/M2 polarization and mitochondrial function of rat macrophages. The rat macrophages and rat myocardial fibroblasts were co-cultured to explore the effect of butyrate on rat myocardial fibroblasts. In addition, MF rats were fed with butyric acid diet.

Results

Compared with the Sham group, collagen deposition in the MF group was increased, and fibrosis was serious. The abundance of Desulfovibrionaceae and Helicobacteraceae in the MF group was increased compared with the Sham group. Gut epithelial cells were destroyed in the MF group compared with the Sham group. Compared with the Sham group, LPS content in the MF group was increased and butyric acid was decreased. Butyrate inhibited M1 and promoted M2. Furthermore, butyrate may promote mitochondrial function recovery by regulating M1/M2 polarization of macrophages. After adding butyrate, cell proliferation ability was decreased, and aging and apoptosis were increased, which indicated that butyrate inhibited rat myocardial fibroblasts activity. Moreover, butyric acid could protect mitochondria and improve the symptoms of rats with MF.

Conclusions

Butyric acid ameliorated MF by regulating M1/M2 polarization of macrophages and promoting recovery of mitochondrial function.

The Role of the Gut Microbiota in the Development of Ischemic Stroke

An increasing number of studies have focused on the gut microbiota and its relationship with various neurological diseases. The gut microbiota can affect the metabolic status of the body, in addition to having an important impact on blood pressure, blood glucose, and atherosclerosis, all of which are risk factors for ischemic stroke. In this review, we summarized studies that included the physiological function of the gut microbiota and gut microbiota disorders related to the central nervous system, thus providing novel ideas for the prevention and treatment of ischemic stroke.

Structural Characteristics and Immunomodulatory Effects of a Long-Chain Polysaccharide From Laminaria japonica

Polysaccharides derived from Laminaria japonica (LJPS) have shown a variety of beneficial effects on improving human health; however, the structural features and bioactivities of long-chain LJPS remain unclear. This study aimed to investigate the structural characteristics and bioactivities of a novel long-chain LJPS. Results showed that the LJPS was composed of Fuc, Rha, Ara, Gal, Glc, Xyl, Man, Fru, Rib, GalA, GluA, GlcA, and ManA, with a molar ratio of 35.71:1.48:0.28:13.16:0.55:2.97:6.92:0.58:0.41:0.14:3.16:15.84:18.79. Of these, Fuc, Gal, Man, GlcA, and ManA were the predominant components with an accumulated proportion of 93.6%. The LJPS was found to consist of seven types of the monomer residues, and the main interchain glycosidic linkages were β -D-(1 → 2), α -D-(1 → 3), (1 → 4), and (1 → 6), and the molecular mass was 5.79 × 10⁴ g/mol. Regarding the molecular conformation, LJPS was a multi-branched, long-chain macromolecule, and appeared in a denser crosslinking network with highly branched and helix domains in the terms of morphology. Additionally, the LJPS had no toxicity to mouse macrophage cells and exhibited biphasic immuno-modulating capacity. The present findings suggested that the long-chain LJPS might be an attractive candidate as an immunopotentiating and anti-inflammatory functional food, and this study also provides a feasible approach to decipher the structural characteristics and spatial conformations of plant-derived polysaccharides.

Phycocyanin Ameliorates Colitis-Associated Colorectal Cancer by Regulating the Gut Microbiota and the IL-17 Signaling Pathway

Phycocyanin (PC) is a pigment-protein complex. It has been reported that PC exerts anti-colorectal cancer activities, although the underlying mechanism has not been fully elucidated. In the present study, azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mice were orally administrated with PC, followed by microbiota and transcriptomic analyses to investigate the effects of PC on colitis-associated cancer (CAC). Our results indicated that PC ameliorated AOM/DSS induced inflammation. PC treatment significantly reduced the number of colorectal tumors and inhibited proliferation of epithelial cell in CAC mice. Moreover, PC reduced the relative abundance of Firmicutes, Deferribacteres, Proteobacteria and Epsilonbacteraeota at phylum level. Transcriptomic analysis showed that the expression of genes involved in the intestinal barrier were altered upon PC administration, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed the IL-17 signaling pathway was affected by PC treatment. The study demonstrated the protective therapeutic action of PC on CAC.

Exogenous lipase administration alters gut microbiota composition and ameliorates Alzheimer's disease-like pathology in APP/PS1 mice

Alzheimer's disease (AD) represents the most common form of dementia in the elderly with no available disease modifying treatments. Altered gut microbial composition has been widely acknowledged as a common feature of AD, which potentially contributes to progression or onset of AD. To assess the hypothesis that Candida rugosa lipase (CRL), which has been shown to enhance gut microbiome and metabolite composition, can rebalance the gut microbiome composition and reduce AD pathology, the treatment effects in APPswe/PS1de9 (APP/PS1) mice were investigated. The analysis revealed an increased abundance of Acetatifactor and Clostridiales vadin BB60 genera in the gut; increased lipid hydrolysis in the gut lumen, normalization of peripheral unsaturated fatty acids, and reduction of neuroinflammation and memory deficits post treatment. Finally, we demonstrated that the evoked benefits on memory could be transferred via fecal matter transplant (FMT) into antibiotic-induced microbiome-depleted (AIMD) wildtype mice, ameliorating their memory deficits. The findings herein contributed to improve our understanding of the role of the gut microbiome in AD's complex networks and suggested that targeted modification of the gut could contribute to amelioration of AD neuropathology.

Improvement of the Gut Microbiota In Vivo by a Short-Chain Fatty Acids-Producing Strain Lactococcus garvieae CF11

Gut microbiota has strong connections with health. Regulating and enhancing gut microbiota and increasing the population of beneficial microorganisms constitutes a new approach to increasing the efficiency of health status. Although it has been shown that Lactococcus can adjust gut microbiota and be beneficial for the host, little is known about whether strains of Lactococcus petauri can improve the gut microbiota. This study focused on the influence of Lactococcus petauri CF11 on the gut microbiome composition and the levels of short-chain fatty acids (SCFAs) in vivo in healthy Sprague Dawley rats. The present results showed that strain CF11 was able to induce a higher amount of fecal acetic acid and propionic acid and enhance species richness. Moreover, strain CF11 improved the gut microbiota community structure. In the experimental group, the genera Oscillospira, Coprococcus, and Ruminococcus, which are reported to be able to produce SCFAs, are significantly increased when compared with the control group (p < 0.05). Finally, the functions of genes revealed that 180 pathways were upregulated or downregulated in comparison with the control group. Among them, the top-five clearly enriched pathways regarding metabolism included porphyrin and chlorophyll metabolism; C5-Branched dibasic acid metabolism; valine, leucine, and isoleucine biosynthesis; phenylalanine, tyrosine, and tryptophan biosynthesis; and ascorbate and aldarate metabolism. Our data suggest that the SCFAs-producing strain CF11 is a potential probiotic.

Ulva prolifera polysaccharide exerts anti-obesity effects via upregulation of adiponectin expression and gut microbiota modulation in high-fat diet-fed C57BL/6 mice

Obesity is characterized by metabolic disorder and accompanying an altered and less diverse gut microbiota composition during a fat-enriched diet. Recent studies indicated that sulphated polysaccharide prevents high-fat diet (HFD) induced obesity, reduces metabolic disorder, and restores the gut microbiota. However, there are few studies about Ulva prolifera polysaccharide (UPP) may induce anti-obesogenic effects. Therefore, the present study investigates the enzymatic extracted UPP effects in HFD-fed mice. The results showed that UPP considerably slowed down the HFD-induced weight gain and improved metabolic disorders in HFD-fed mice. Notably, the effects were associated with lower body weight gain, reduced adipose tissue hypertrophy, triglyceride concentration in liver and systemic low-grade inflammation, and improved fasting blood glucose. Moreover, our result reveals that UPP may elevate the expression of AMPK via adiponectin activation. Interestingly, we found that UPP may induce PPARα agonist to enhance β-oxidation since the elevation of CPT-1 and PPARα expression simultaneously. Meanwhile, gut microbiota analysis revealed UPP promoted the growth of Parasutterella, Feacalibaculum, and Bifidobacterium, and reduced the abundance of Acetatifactor, Tyzerella, Ruminococcus_1, and Desulfovibrio. The changes in microbiota may have a positively correlated effect on improving obesity and metabolic abnormalities. UPP may prevent HFD-induced obesity and associated metabolic diseases, as well as modulate the composition of gut microbiota to facilitate the growth of probiotics.

Microbial hydrogen economy alleviates colitis by reprogramming colonocyte metabolism and reinforcing intestinal barrier

With the rapid development and high therapeutic efficiency and biosafety of gas-involving theranostics, hydrogen medicine has been particularly outstanding because hydrogen gas (H₂), a microbial-derived gas, has potent anti-oxidative, anti-apoptotic, and anti-inflammatory activities in many disease models. Studies have suggested that H₂-enriched saline/water alleviates colitis in murine models; however, the underlying mechanism remains poorly understood. Despite evidence demonstrating the importance of the microbial hydrogen economy, which reflects the balance between H₂-producing (hydrogenogenic) and H₂-utilizing (hydrogenotrophic) microbes in maintaining colonic mucosal ecosystems, minimal efforts have been exerted to manipulate relevant H₂-microbe interactions for colonic health. Consistent with previous studies, we found that administration of hydrogen-rich saline (HS) ameliorated dextran sulfate sodium-induced acute colitis in a mouse model. Furthermore, we demonstrated that HS administration can increase the abundance of intestinal-specific short-chain fatty acid (SCFA)-producing bacteria and SCFA production, thereby activating the intracellular butyrate sensor peroxisome proliferator-activated receptor γ signaling and decreasing the epithelial expression of Nos2, consequently promoting the recovery of the colonic anaerobic environment. Our results also indicated that HS administration ameliorated disrupted intestinal barrier functions by modulating specific mucosa-associated mucolytic bacteria, leading to substantial inhibition of opportunistic pathogenic Escherichia coli expansion as well as a significant increase in the expression of interepithelial tight junction proteins and a decrease in intestinal barrier permeability in mice with colitis. Exogenous H₂ reprograms colonocyte metabolism by regulating the H₂-gut microbiota-SCFAs axis and strengthens the intestinal barrier by modulating specific mucosa-associated mucolytic bacteria, wherein improved microbial hydrogen economy alleviates colitis.

Immunoregulatory Intestinal Microbiota and COVID-19 in Patients with Type Two Diabetes: A Double-Edged Sword

Coronavirus disease 2019, or COVID-19, is a major challenge facing scientists worldwide. Alongside the lungs, the system of organs comprising the GI tract is commonly targeted by COVID-19. The dysbiotic modulations in the intestine influence the disease severity, potentially due to the ability of the intestinal microbiota to modulate T lymphocyte functions, i.e., to suppress or activate T cell subpopulations. The interplay between the lungs and intestinal microbiota is named the gut-lung axis. One of the most usual comorbidities in COVID-19 patients is type 2 diabetes, which induces changes in intestinal microbiota, resulting in a pro-inflammatory immune response, and consequently, a more severe course of COVID-19. However, changes in the microbiota in this comorbid pathology remain unclear. Metformin is used as a medication to treat type 2 diabetes. The use of the type 2 diabetes drug metformin is a promising treatment for this comorbidity because, in addition to its hypoglycemic action, it can increase amount of intestinal bacteria that induce regulatory T cell response. This dual activity of metformin can reduce lung damage and improve the course of the COVID-19 disease.

Prebiotic Supplementation During Gestation Induces a Tolerogenic Environment and a Protective Microbiota in Offspring Mitigating Food Allergy

Food allergy is associated with alterations in the gut microbiota, epithelial barrier, and immune tolerance. These dysfunctions are observed within the first months of life, indicating that early intervention is crucial for disease prevention. Preventive nutritional strategies with prebiotics are an attractive option, as prebiotics such as galacto-oligosaccharides and inulin can promote tolerance, epithelial barrier reinforcement, and gut microbiota modulation. Nonetheless, the ideal period for intervention remains unknown. Here, we investigated whether galacto-oligosaccharide/inulin supplementation during gestation could protect offspring from wheat allergy development in BALB/cJRj mice. We demonstrated that gestational prebiotic supplementation promoted the presence of beneficial strains in the fecal microbiota of dams during gestation and partially during mid-lactation. This specific microbiota was transferred to their offspring and maintained to adulthood. The presence of B and T regulatory immune cell subsets was also increased in the lymph nodes of offspring born from supplemented mothers, suggestive of a more tolerogenic immune environment. Indeed, antenatal prebiotic supplementation reduced the development of wheat allergy symptoms in offspring. Our study thus demonstrates that prebiotic supplementation during pregnancy induces, in the offspring, a tolerogenic environment and a microbial imprint that mitigates food allergy development.

Phycobiliproteins: Structural aspects, functional characteristics, and biotechnological perspectives

Phycobiliproteins (PBPs) are fluorescent proteins of various colors, including fuchsia, purple-blue and cyan, that allow the capture of light energy in auxiliary photosynthetic complexes called phycobilisomes (PBS). PBPs have several highly preserved structural and physicochemical characteristics. In the PBS context, PBPs function is capture luminous energy in the 450-650 nm range and delivers it to photosystems allowing photosynthesis take place. Besides the energy harvesting function, PBPs also have shown to have multiple biological activities, including antioxidant, antibacterial and antitumours, making them an interesting focus for different biotechnological applications in areas like biomedicine, bioenergy and scientific research. Nowadays, the main sources of PBPs are cyanobacteria and micro and macro algae from the phylum Rhodophyta. Due to the diverse biological activities of PBPs, they have attracted the attention of different industries, such as food, biomedical and cosmetics. This is why a large number of patents related to the production, extraction, purification of PBPs and their application as cosmetics, biopharmaceuticals or diagnostic applications have been generated, looking less ecological impact in the natural prairies of macroalgae and less culture time or higher productivity in cyanobacteria to satisfy the markets and applications that require high amounts of these molecules. In this review, we summarize the main structural characteristics of PBPs, their biosynthesys and biotechnological applications. We also address current trends and future perspectives of the PBPs market.

Maternal Long-Term Intake of Inulin Improves Fetal Development through Gut Microbiota and Related Metabolites in a Rat Model

Adequate dietary fiber intake during gestation is critical for maternal-fetal health. This experiment aims to uncover the impacts of maternal long-term intake of inulin on fetal development and its underlying mechanism. Eighty female Sprague-Dawley rats were randomly assigned to two groups receiving either a fiber-free diet or an inulin diet (inulin) for three parities. On the 19^th day of pregnancy in the third parity, blood, intestinal, placental, and colonic digesta samples were collected. Results showed that maternal intake of inulin significantly decreased the within-litter birth weight variation in parities 2 and 3. Inulin intake modified the gut microbiome profiles and elevated the colonic contents of short chain fatty acids (propionate and butyrate). Inulin decreased the serotonin (5-HT) concentration in the colon, whereas it increased the 5-HT concentrations in serum and placenta and the number of 5-HT⁺ enterochromaffin cells in the colon. The protein expression of melatonin-synthesizing enzyme (arylalkylamine N-acetyltransferase) and the melatonin concentration in the placenta were also increased by inulin. Inulin improved the placental redox status and nutrient transport. These findings indicated that maternal long-term intake of inulin improves fetal development by altering the intestinal microbiota and related metabolites in rats.

Restorative Effects of Inulin From Codonopsis pilosula on Intestinal Mucosal Immunity, Anti-Inflammatory Activity and Gut Microbiota of Immunosuppressed Mice

An inulin (CPPF), isolated from a traditional Chinese herbal medicine Codonopsis pilosula, was characterized and demonstrated with potential prebiotic activity in vitro before. Based on its non-digested feature, the intestinal mucosa and microbiota modulatory effects in vivo on immunosuppressed mice were investigated after oral administration of 200, 100 and 50 mg/kg of CPPF for 7 days. It was demonstrated that the secretions of sIgA and mucin 2 (Muc2) in ileum were improved by CPPF, and the anti-inflammatory activities in different intestine parts were revealed. The intestine before colon could be the target active position of CPPF. As a potential prebiotic substance, a gut microbiota restorative effect was also presented by mainly modulating the relative abundance of Eubacteriales, including Oscillibacter, unidentified Ruminococcus and Lachnospiraceae after high-throughput pyrosequencing of V4 region of 16S rRNA analysis. All these results indicated that this main bioactive ingredient inulin from C. pilosula was a medicinal prebiotic with enhancing mucosal immune, anti-inflammatory and microbiota modulatory activities.

Pharmacokinetics, bioavailability and tissue distribution of chitobiose and chitotriose in rats

Chitooligosaccharides (COSs) have various physiological activities and broad application prospects; however, their pharmacokinetics and tissue distribution remain unclear. In this study, a sensitive and selective ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) method for determining chitobiose (COS 2) and chitotriose (COS 3) in rat serum and tissues was developed. This method was successfully validated based on FDA guidelines in terms of selectivity, calibration curves (lower limit of quantification was 0.002 µg/mL for COS 2 and 0.02 µg/mL for COS 3), precision (intra-day relative standard deviation of 0.04%-3.55% and inter-day relative standard deviation of 1.94%-11.63%), accuracy (intra-day relative error of - 1.81%-11.06% and inter-day relative error of - 9.41%-8.63%), matrix effects, recovery (97.10%-101.29%), stability, dilution integrity, and carry-over effects. Then, the method was successfully applied to the pharmacokinetics and tissue distribution study of COS 2 and COS 3 after intragastric and intravenous administration. After intragastric administration, COS 2 and COS 3 were rapidly absorbed, reached peak concentrations in the serum after approximately 0.45 h, and showed rapid elimination with clearances greater than 18.82 L/h/kg and half-lives lower than 6 h. The absolute oral bioavailability of COS 2 and COS 3 was 0.32%-0.52%. COS 2 and COS 3 were widely distributed in Wistar rat tissues and could penetrated the blood-brain barrier without tissue accumulation.

Gut microbiota and short chain fatty acids partially mediate the beneficial effects of inulin on metabolic disorders in obese ob/ob mice

Mounting evidence has linked both obesity and metabolic disorders with dysbiosis of the gut microbiota. Dietary inulin is conducive to modulating this dysbiosis, and represents a potential means to improve disorders of glucose and lipid metabolism. However, the mechanisms underlying these improvements are largely unclear. Obese ob/ob mice were fed a standard chow, a low fiber diet (LFD) or a high fiber diet (HFD) for 4 weeks, and the body weight, fecal short chain fatty acids (SCFAs) level, and plasma and liver lipid profiles were analyzed. Oral glucose tolerance testing, and gut microbiota sequencing were also conducted. Dietary inulin improved the dysbiosis of the gut microbiota, attenuated the decrease in phylum Bacteroidetes, repressed the increase of phylum Firmicutes, and led to an increase in the ratio of Firmicutes/Bacteroidetes. At the family level, inulin promoted the expansion of SCFAs-producing Ruminococcaceae and Lachnospiraceae bacteria, which increased the fecal SCFAs concentrations. At the genus level, inulin increased the levels of Bacteroides and Bifidobacteria. Furthermore, our results revealed that there was enhanced expression of angiopoietin-like protein 4 (ANGPTL4), which might be induced by the higher production of SCFAs, and this may underlie the improvements in the disorders of glucose and lipid metabolism seen in mice with added dietary inulin. In conclusion, inulin may ameliorate metabolic disorders by remodeling the gut microbiota and increasing the production of SCFAs, which might be mediated by the ANGPTL4-related signaling pathway. Interventions targeting the gut microbiota warrant further investigation as a novel therapy for metabolic diseases. PRACTICAL APPLICATIONS: Mounting evidence has linked both obesity and metabolic disorders with dysbiosis of the gut microbiota. Dietary inulin is conducive to modulating this dysbiosis, and represents a potential means to improve disorders of glucose and lipid metabolism. However, the mechanisms underlying these improvements are largely unclear. In the present study, we investigated the effects of dietary fiber (inulin) on metabolic homeostasis using ob/ob mice. The results of our study demonstrate that inulin-induced remodeling of the gut microbiota resulted in increased production of short chain fatty acids (SCFAs), leading to the enhanced expression of angiopoietin-like protein 4 (ANGPTL4), which improved the glucose and lipid metabolism. Our results suggest that the gut microbiota, SCFAs and ANGPTL4 pathway at least partially mediate the beneficial effects of inulin on metabolic disorders in ob/ob mice.

Preparation, characterization, and bioactivity evaluation of oligosaccharides from Atractylodes lancea (Thunb.) DC

Sixteen oligosaccharide monomers with the degree of polymerization 3 to 18 (DP 3 to DP 18) and three active fractions (DP 3-9, DP 8-11, and DP 11-17) were separated from Atractylodes lancea (Thunb.) DC. by optimized fast protein liquid chromatography coupled with refractive index detector (FPLC-RID) and preparation hydrophilic interaction chromatography (Pre-HILIC). Gas chromatography-mass spectrometer (GC-MS), liquid chromatography tandem mass spectrometry (LC-MS/MS), nuclear magnetic resonance (NMR) spectroscopy, and methylation analysis showed that the oligosaccharide in A. lancea was 1-kestose [β-D-fructofuranosyl-(2 → 1)-β-D-fructofuranosyl-(2 → 1)-α-D-glucopyranoside] (inulin-type fructooligosaccharides, FOS). Particularly, DP 3-9 showed the best capacity in stimulating phagocytic, NO, and cytokines production on RAW264.7 cells than any other purified oligosaccharide monomers and active fractions. It could also activate T-cells in Peyer's patch cells and enhance the production of colony stimulation factors. Besides, FPLC-RID showed a good capacity for large-scale preparation of DP 3-9 with the recovery of more than 93%. The bioactivity of sixteen FOS monomers (DP 3 to DP 18) and three FOS fractions (DP 3-9, DP 8-11, and DP 11-17) investigated in this study are beneficial for the utilization of FOS as a functional ingredient in novel product development.