Intestinal Epithelial Cell Exosome Launches IL-1β-Mediated Neuron Injury in Sepsis-Associated Encephalopathy

BackgroundGut–microbiota–brain axis links the relationship between intestinal microbiota and sepsis-associated encephalopathy (SAE). However, the key mediators between them remain unclear.MethodsMemory test was determined by Water maze. Intestinal flora was measured by 16S RNA sequencing. Neurotransmitter was detected by high-performance liquid chromatography (HPLC). Histopathology was determined by H&E, immunofluorescence (IF), and terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) staining. Flow cytometry was employed to determine the proportion of macrophages.ResultsFecal microbiota transplantation (FMT) relieved hippocampus impairment of SAE rats by inhibiting inflammation cytokine secretion, the expression of IBA-1 and neurotransmitter disturbance, and cell apoptosis and autophagy, accompanied by the reduced M1 polarization and M1 pro-inflammation factors produced by macrophages in mesenteric lymph nodes (MLNs). Actually, M1 polarization in SAE rats depended on intestinal epithelial cell (IEC)-derived exosome. GW4869-initiated inhibition of exosome secretion notably abolished M1 polarization and the secretion of IL-1β. However, GW4869-mediated improvement of hippocampus impairment was counteracted by the delivery of recombinant interleukin (IL)-1β to hippocampus. Mechanistically, IEC-derived exosome induced the excessive circulating IL-1β produced by CP-R048 macrophages, which subsequently induced damage and apoptosis of hippocampal neurons H19-7 in an autophagy-dependent manner. And reactivation of autophagy facilitates intestinal IL-1β-mediated hippocampal neuron injury.ConclusionCollectively, intestinal flora disturbance induced the exosome release of IECs, which subsequently caused M1 polarization in MLNs and the accumulation of circulating IL-1β. Circulating IL-1β promoted the damage and apoptosis of neurons in an autophagy-dependent manner. Possibly, targeting intestinal flora or IEC-derived exosome contributes to the treatment of SAE.

A Review on the Immunomodulatory Mechanism of Acupuncture in the Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a chronic inflammatory disease with a high prevalence and canceration rate. The immune disorder is one of the recognized mechanisms. Acupuncture is widely used to treat patients with IBD. In recent years, an increasing number of studies have proven the effectiveness of acupuncture in the treatment of IBD, and some progress has been made in the mechanism. In this paper, we reviewed the studies related to acupuncture for IBD and focused on the immunomodulatory mechanism. We found that acupuncture could regulate the innate and adaptive immunity of IBD patients in many ways. Acupuncture exerts innate immunomodulatory effects by regulating intestinal epithelial barrier, toll-like receptors, NLRP3 inflammasomes, oxidative stress, and endoplasmic reticulum stress and exerts adaptive immunomodulation by regulating the balance of Th17/Treg and Th1/Th2 cells. In addition, acupuncture can also regulate intestinal flora.

Physicochemical Properties of the Soluble Dietary Fiber from Laminaria japonica and Its Role in the Regulation of Type 2 Diabetes Mice

Laminaria japonica is a large marine brown alga that is annually highly productive. However, due to its underutilization, its potential value is substantially wasted. For example, a lot of Laminaria japonica cellulose remains unused during production of algin. The soluble dietary fiber (SDF) was prepared from the byproducts of Laminaria japonica, and its physicochemical properties were explored. SDF exhibits good water-holding, oil-holding, water-absorbing swelling, glucose and cholesterol absorption capacity, and inhibitory activity of α-amylase and α-glucosidase. In addition, the beneficial effects of SDF in diabetic mice include reduced body weight, lower blood glucose, and relieved insulin resistance. Finally, the intestinal flora and metabolomic products were analyzed from feces using 16S amplicon and LC-MS/MS, respectively. SDF not only significantly changed the composition and structure of intestinal flora and intestinal metabolites, but also significantly increased the abundance of beneficial bacteria Akkermansia, Odoribacter and Bacteroides, decreased the abundance of harmful bacteria Staphylococcus, and increased the content of bioactive substances in intestinal tract, such as harmine, magnolol, arachidonic acid, prostaglandin E2, urimorelin and azelaic acid. Taken together, these findings suggest that dietary intake of SDF alleviates type 2 diabetes mellitus disease, and provides an important theoretical basis for SDF to be used as a functional food.

Association Between Breastmilk Microbiota and Food Allergy in Infants

Regulating the composition of human breastmilk has the potential to prevent allergic diseases early in life. The composition of breastmilk is complex, comprising varying levels of oligosaccharides, immunoactive molecules, vitamins, metabolites, and microbes. Although several studies have examined the relationship between different components of breastmilk and infant food allergies, few have investigated the relationship between microorganisms in breastmilk and infant food allergy. In the present study, we selected 135 healthy pregnant women and their full-term newborns from a cohort of 202 mother–infant pairs. Among them, 69 infants were exclusively breastfed until 6 mo after birth. At follow-up, 11 of the 69 infants developed a food allergy in infancy while 22 showed no signs of allergy. Thirty-three breastmilk samples were collected within 1 mo after delivery, and 123 infant fecal samples were collected at five time points following their birth. These samples were analyzed using microbial 16S rRNA gene sequencing. The abundance and evenness of the milk microbiota and the number of differential bacteria were higher in the breastmilk samples from the non-allergy group than in those from the food allergy group. The non-allergy group showed relatively high abundance of Bifidobacterium, Akkermansia, Clostridium IV, Clostridium XIVa, Veillonella, and butyrate-producing bacteria such as Fusobacterium, Lachnospiraceae incertae sedis, Roseburia, and Ruminococcus. In contrast, the abundance of Proteobacteria, Acinetobacter, and Pseudomonas in breastmilk was higher in the food allergy group. A comparison of the changes in dominant differential breastmilk microbiota in the intestinal flora of the two groups of infants over time revealed that the changes in Bifidobacterium abundance were consistent with those in the breastmilk flora. Functional pathway prediction of breastmilk microflora showed that the enhancement of the metabolic pathways of tyrosine, tryptophan, and fatty acids was significantly different between the groups. We suggest that changes in the breastmilk microbiota can influence the development of food allergies. Breastmilk contains several microbes that have protective effects against food allergies, both by influencing the colonization of intestinal microbiota and by producing butyrate. This study may provide new ideas for improving infant health through early intervention with probiotics.

Protective Effects of Honey-Processed Astragalus on Liver Injury and Gut Microbiota in Mice Induced by Chronic Alcohol Intake

Honey-processed Astragalus (HPA) is a mixture of Astragalus and honey, which is a processed product of Chinese medicine. It has the active ingredients of Astragalus and the unique effects of honey. However, the mechanism of HPA for improving alcoholic liver disease (ALD) is not clear. The purpose of this study is to explore the ameliorating effect and mechanism of HPA (4 and 8 g/kg bw) on alcoholic liver injury. Two doses of HPA were orally administered to alcohol-treated mice for four weeks. The results showed that HPA could effectively reduce triglycerides (TG) by 59% and free fat acid (FFA) and total cholesterol (TC) in serum and hepatic were reduced by least 25.9%. HPA could cause a decrease in serum low-density lipoprotein cholesterol (LDL-C) from 0.145 mM to 0.117 mM, and the serum high-density lipoprotein cholesterol (HDL-C) was increased. After alcohol-treated mice were supplemented with HPA, antioxidant markers (superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and Glutathione peroxidase (GSH-Px)), liver function index (alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP)), proinflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β)), and liver tissue were all significantly improved. This is related to the fact that HPA can promote the expression of oxidative stress-related genes and inhibit the expression of inflammation-related genes. In addition, HPA could also regulate the disturbance of the intestinal microflora. In general, HPA could significantly improve the accumulation of serum and liver lipids caused by alcohol and the imbalance of intestinal flora in mice. It could also improve liver function, oxidative stress, and inflammation.

First Report of Fecal Microflora of Wild Bar-Headed Goose in Tibet Plateau

The bar-headed goose (Anser indicus) has two black spots on its head. It is considered an important bird in China. It breeds in plateau lakes, especially saltwater lakes, and swamp areas. However, the intestinal flora of wild bar-headed geese in the Tibet Autonomous Region is currently not known. In this study, 16S rDNA sequencing was performed on the intestinal microbes of wild bar-headed geese. A total of 513,505 reads of raw data were obtained, and the results analyzed the average number of 128,376 ± 2,392 reads per sample. The microbiota of all samples consists of 10 main bacterial phyla, including Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria, Cyanobacteria, Patescibacteria, Deferribacteres, Planctomy-cetes, Fusobacteria, and Tenericutes. The results indicated that Firmicutes (67.34%) was the predominant phylum, followed by Proteobacteria (29.03%) and Cyanobacteria (1.97%). In our research, we identified the intestinal flora of the wild bar-headed goose, which provides valuable information for further research on the gene function of the bar-headed goose and the intestinal flora of wild animals. These findings are also useful and valuable for genetic and high-altitude research in the Tibet Autonomous Region.

Gut Microbiota and Metabolome Alterations Associated with Chinese Monks’ Practice

BackgroundThe practices of monks mainly include long-term vegetarianism and meditation, which are likely to fundamentally influence the gut microbiota and fecal metabolites. We aim to study the relationship between the practices of Chinese monks and gut microbiotas and metabolites.MethodsTwenty-four monks and forty-eight omnivorous controls (never meditated) were included. The microbiotas of all samples were profiled by 16S rRNA gene sequencing, and the metabolomes were examined by nontargeted LC–MS metabolomics. Twenty-four monks were divided into the H group and the L group according to the median time of practice, and microbiota and metabolite analyses were carried out in the two groups.ResultsMicrobial communities and metabolites were decreased in monks. Bacteroidetes was increased in monks, while the Firmicutes, Actinobacteria, and Firmicutes/Bacteroidetes ratios were decreased. At the genus level, Faecalibacterium, Lachnospira, Roseburia, norank_f__Lachnospiraceae, etc. were higher in monks, while Blautia, Eubacterium__hallii_group, Bifidobacteria, etc. were lower (all p < 0.05). Most identical KEGG categories in both Tax4Fun and PICRUSt2 were related to metabolism (6/8, 75.0%). Most higher abundance genera were positively correlated with higher abundance metabolites in monks, indicating that intestinal flora significantly affects intestinal metabolic function. Lipids and lipid-like molecules were the major differential metabolites (VIP >2, p < 0.05) in the two groups. L-dopa plays an important role in many metabolic pathways in monks. Prevotella_9 was enriched in the L group, while norank_f__Lachnospiraceae was enriched in the H group. DG (16:0/18:0/0:0) was highly expressed in the H group and participated in sixteen KEGG functional pathways as well as many immune-related KEGG enrichment pathways.ConclusionThe monks' lifestyle practices of vegetarianism and meditation have the potential to modulate human metabolism and function by affecting the gut microbial composition and metabolites. The appropriate practice of monks makes the intestine younger and increases immunity, but long-term practice may cause adverse physical and mental events.

Comparison and Analysis of Gut Microbiota in Children With IgA Vasculitis With Different Clinical Symptoms

Background: Henoch-Schönlein purpura, now called immunoglobulin A (IgA) vasculitis, is a common autoimmune disease in children, its association with gut microbiota composition remains unknown.Methods: The collected cases were divided into three groups: G1 group of simple skin type, G2 group with no digestive tract expression, G3 group of mixed digestive tract, and C group of healthy children. The fecal samples of each group of children were collected and the sequencing data was processed and analyzed. The dilution curve reflected the reasonableness of the amount of sequencing data.Results: The number of species composition sequences in the G1, G2 and G3 groups was lower than that in the C group, especially for the G2 and G3 groups. The four most abundant bacteria were Bacteroidetes, Firmicutes, Proteobacteria and Actinobacteria. The relative abundance of Proteobacteria in the G2 and G3 groups was significantly higher than that in the G1 and C groups, while the relative abundance of Actinobacteria was significantly reduced, and the relative abundance of Actinobacteria in the G1 group was lower than that in the C group. Principal component analysis of the UPGMA clustering tree and each group of samples showed that the microbial community composition of the same group of samples was similar.Conclusions: The abundance of intestinal microbes in children with IgA vasculitis is lower than in normal children. Bacteroidetes, Firmicutes, Proteobacteria and Actinobacteria are the four most abundant bacteria in the intestinal flora of children. Proteobacteria and Actinobacteria are associated with organ involvement in IgA vasculitis.