Calceolarioside B inhibits SARS-CoV-2 Omicron BA.2 variant cell entry and modulates immune response

This study evaluated the inhibitory effects of calceolarioside B, extracted from the traditional Chinese herb Mutong (Akebia quinata Thumb), on the SARS-CoV-2 Omicron BA.2 variant. Molecular docking and molecular dynamics simulations predicted the binding sites and interactions between calceolarioside B and the Omicron BA.2 spike (S) protein. Biolayer interferometry (BLI) and immunofluorescence assays validated its high-affinity binding. Pseudovirus entry assays assessed the inhibitory effects of calceolarioside B on viral entry into host cells, while enzyme-linked immunosorbent assay (ELISA) measured inflammatory cytokine levels. Flow cytometry was used to analyze its effects on macrophage phenotype switching. Results demonstrated that calceolarioside B could bind to the Omicron BA.2 S protein with high affinity, and significantly inhibited viral entry into host cells by interfering with the binding of angiotensin-converting enzyme 2 (ACE2) receptor and S protein. Additionally, calceolarioside B reduced IL(interleukin)-6 expression levels and promoted the switch of macrophages from the pro-inflammatory M1 phenotype to the anti-inflammatory M2 phenotype. These findings suggest that calceolarioside B possesses antiviral and immunomodulatory effects, making it a potential dual-function inhibitor for the treatment of COVID-19.

Effects of Several Tea-like Plants on Liver Injury Induced by Alcohol via Their Antioxidation, Anti-Inflammation, and Regulation of Gut Microbiota

Liver injury induced by alcohol is a serious global health problem. Several tea-like plants are widely used as beverages, which are drunk like tea. In this study, the hepatoprotective effects of eight tea-like plant extracts with the intake of 200 mg/kg.bw/day were investigated and compared using a C57BL/6J mouse model of acute alcohol exposure, including sweet tea, vine tea, Rabdosia serra kudo, broadleaf holly leaf, mulberry leaf, bamboo leaf, Camellia nitidissima, and Akebia trifoliata peels. The results showed that the eight tea-like plants had hepatoprotective effects to different degrees against acute alcohol exposure via enhancing the activities of alcoholic metabolism enzymes, ameliorating oxidative stress and inflammation in the liver, as well as regulating gut microbiota. In particular, sweet tea, bamboo leaf, mulberry leaf, and Camellia nitidissima increased the activities of alcohol dehydrogenase or aldehyde dehydrogenase. Among these tea-like plants, sweet tea and Camellia nitidissima had the greatest hepatoprotective effects, and their bioactive compounds were determined by high-performance liquid chromatography. Chlorogenic acid, rutin, and ellagic acid were identified in sweet tea, and epicatechin, rutin, and ellagic acid were identified in Camellia nitidissima, which could contribute to their hepatoprotective action. These tea-like plants could be drunk or developed into functional food against alcoholic liver injury, especially sweet tea and Camellia nitidissima. In the future, the effects of sweet tea and Camellia nitidissima on chronic alcoholic liver diseases should be further investigated.

Quercetin Increases Growth Performance and Decreases Incidence of Diarrhea and Mechanism of Action in Weaned Piglets

This study aimed to investigate the mechanism of quercetin increasing growth performance and decreasing incidence of diarrhea in weaned piglets. Forty-eight Duroc × Landrace × Large White weaned piglets with similar body weight (7.48 ± 0.20 kg, 28 days of age) were randomly divided into four treatments (control, 250 mg/kg quercetin, 500 mg/kg quercetin, and 750 mg/kg quercetin treatments) and fed with basal diet or experimental diet supplemented with quercetin. Performance, diarrhea rate and index, and content of serum anti-inflammatory factors were determined and calculated in weaned piglets; colonic flora and signaling pathways related to anti-inflammation were measured using 16S rDNA sequencing and RNA-seq, respectively. The results showed that compared with control, feed-to-gain ratio and content of serum interferon gamma (IFN-γ) were significantly decreased in the 500 and 750 mg/kg quercetin treatments (P < 0.05); quercetin significantly decreased diarrhea rate and diarrhea index (P < 0.05) and significantly increased the content of serum transforming growth factor (TGF-β) in weaned piglets (P < 0.05); the content of serum NF-κB was significantly decreased in the 750 mg/kg quercetin treatment (P < 0.05); moreover, quercetin significantly increased diversity of colonic flora (P < 0.05), and at the phylum level, the relative abundance of Actinobacteria in the 500 and 750 mg/kg treatments was significantly increased (P < 0.05), and the relative abundance of Proteobacteria in the three quercetin treatments were significantly decreased (P < 0.05) in the colon of weaned piglets; at the genus level, the relative abundance of Clostridium-sensu-stricto-1, Turicibacter, unclassified_f_Lachnospiraceae, Phascolarctobacterium, and Family_XIII _AD3011_group was significantly increased (P < 0.05); the relative abundance of Subdollgranulum and Blautia was significantly decreased in the 500 and 750 mg/kg treatments (P < 0.05); the relative abundance of Eschericha-Shigella, Terrisporobacter, and Eubacterium-coprostanoligenes was significantly increased (P < 0.05); the relative abundance of Streptocococcus, Sarcina, Staphylococcus, and Ruminococcaceae_UCG-008 was significantly decreased in the three quercetin treatments (P < 0.05); the relative abundance of Ruminococcaceae_UCG_014 was significantly increased in the 250 mg/kg quercetin treatment in the colon of weaned piglets (P < 0.05). The results of Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that differentially expressed genes (DEGs) from the quercetin treatments were significantly enriched in nuclear transcription factor-κB (NF-κB) signal pathway (P < 0.05); mRNA expression of tumor necrosis factor-α (TNF-α), interleukin-1R1 (IL-1R1), conserved helix-loop-helix ubiquitous kinase (CHUK), toll-like receptor 4 (TLR4), and IL-1β from quercetin treatments were significantly decreased in colonic mucosa of weaned piglets (P < 0.05). In summary, quercetin increased feed conversion ratio and decreased diarrhea through regulating NF-κB signaling pathway, controlling the balance between anti-inflammatory and proinflammatory factors, and modulating intestinal flora, thus promoting the absorption of nutrients in weaned piglets. These results provided the theoretical foundation for applying quercetin in preventing weaning piglets' diarrhea and animal husbandry practices.

From ancient wisdom to modern science: Gut microbiota sheds light on property theory of traditional Chinese medicine

The property theory of traditional Chinese medicine (TCM) has been practiced for thousands of years, playing a pivotal role in the clinical application of TCM. While advancements in energy metabolism, chemical composition analysis, machine learning, ion current modeling, and supercritical fluid technology have provided valuable insight into how aspects of TCM property theory may be measured, these studies only capture specific aspects of TCM property theory in isolation, overlooking the holistic perspective inherent in TCM. To systematically investigate the modern interpretation of the TCM property theory from multidimensional perspectives, we consulted the Chinese Pharmacopoeia (2020 edition) to compile a list of Chinese materia medica (CMM). Then, using the Latin names of each CMM and gut microbiota as keywords, we searched the PubMed database for relevant research on gut microbiota and CMM. The regulatory patterns of different herbs on gut microbiota were then summarized from the perspectives of the four natures, the five flavors and the meridian tropism. In terms of the four natures, we found that warm-natured medicines promoted the colonization of specific beneficial bacteria, while cold-natured medicines boosted populations of some beneficial bacteria while suppressing pathogenic bacteria. Analysis of the five flavors revealed that sweet-flavored and bitter-flavored CMMs positively influenced beneficial bacteria while inhibiting harmful bacteria. CMMs with different meridian tropism exhibited complex modulative patterns on gut microbiota, with Jueyin (Liver) and Taiyin (Lung) meridian CMMs generally exerting a stronger effect. The gut microbiota may be a biological indicator for characterizing the TCM property theory, which not only enhances our understanding of classic TCM theory but also contributes to its scientific advancement and application in healthcare. Please cite this article as: Yang YN, Zhan JG, Cao Y, Wu CM. From ancient wisdom to modern science: Gut microbiota sheds light on property theory of traditional Chinese medicine. J Integr Med 2024; 22(4): 413-445.

Epigallocatechin Gallate Alleviates Staphylococcal Enterotoxin A-Induced Intestinal Barrier Damage by Regulating Gut Microbiota and Inhibiting the TLR4-NF-κB/MAPKs-NLRP3 Inflammatory Cascade

Natural phytochemicals have attracted increasing attention because of their promising ability to tackle bacteriotoxin-induced public safety concerns. However, it is unclear how natural phytochemicals regulate the intestinal barrier dysfunction caused by bacteriotoxin, such as staphylococcal enterotoxin A (SEA). This study aims to illustrate the in vitro and in vivo protective mechanism of epigallocatechin gallate (EGCG) on SEA-triggered intestinal barrier damage and inflammation. Results show that EGCG alleviates intestinal barrier damage by effectively inhibiting SEA-induced intestinal permeability increase, tight junction protein and mucin loss, and intestinal cell apoptosis. EGCG also reduces intestinal inflammation by suppressing the TLR4-NF-κB/MAPKs-NLRP3 pathway. Importantly, EGCG reverses gut microbiota dysbiosis and short-chain fatty acid (SCFA) content decrease induced by SEA. It is worth noting that this study also detects the direct interaction between the phytochemical and virulence factors and finds that EGCG effectively not only inhibits the secretion of SEA but also binds with the secreted SEA to attenuate its toxicity. Taken together, EGCG mitigates SEA-induced intestinal barrier dysfunction via gut microbiota SCFA-mediated TLR4-NF-κB/MAPKs-NLRP3 inflammatory cascade inhibition. Overall, this research provides enlightening insight into the application of bacteriotoxin-targeting natural compounds in the field of food safety and human wellness.

Raspberry polyphenols alleviate neurodegenerative diseases: through gut microbiota and ROS signals

Neurodegenerative diseases are neurological disorders that become more prevalent with age, usually caused by damage or loss of neurons or their myelin sheaths, such as Alzheimer's disease and epilepsy. Reactive oxygen species (ROS) are important triggers for neurodegenerative disease development, and mitigation of oxidative stress caused by ROS imbalance in the human body is important for the treatment of these diseases. As a widespread delicious fruit, the raspberry is widely used in the field of food and medicine because of its abundant polyphenols and other bioactive substances. Polyphenols from a wide variety of raspberry sources could alleviate neurodegenerative diseases. This review aims to summarize the current roles of these polyphenols in maintaining neurological stability by regulating the composition and metabolism of the intestinal flora and the gut-brain axis signal transmission. Especially, we discuss the therapeutic effects on neurodegenerative diseases of raspberry polyphenols through intestinal microorganisms and ROS signals, by means of summary and analysis. Finally, methods of improving the digestibility and utilization of raspberry polyphenols are proposed, which will provide a potential way for raspberry polyphenols to guarantee the health of the human nervous system.

Anti-Inflammatory and Gut Microbiota Modulation Potentials of Flavonoids Extracted from Passiflora foetida Fruits

This study aimed to explore the anti-inflammatory and gut microbiota modulation potentials of flavonoid-rich fraction (PFF) extracted from Passiflora foetida fruits. The results showed that PFF markedly reduced the production of nitric oxide (NO), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) in LPS-stimulated RAW 264.7 cells. Meanwhile, PFF treatment also effectively decreased the phosphorylation levels of MAPK, PI3K/Akt, and NF-κB signaling-pathway-related proteins (ERK, JNK, p38, Akt, and p65). Moreover, PFF had an impact on microbial composition and metabolites in a four-stage dynamic simulator of human gut microbiota (BFBL gut model). Specifically, PFF exhibited the growth-promoting ability of several beneficial bacteria, including Bifidobacterium, Enterococcus, Lactobacillus, and Roseburia, and short-chain fatty acid (SCFA) generation ability in gut microbiota. In addition, spectroscopic data revealed that PFF mainly contained five flavonoid compounds, which may be bioactive compounds with anti-inflammatory and gut microbiota modulation potentials. Therefore, PFF could be utilized as a natural anti-inflammatory agent or supplement to health products.

Colitis-Mediated Dysbiosis of the Intestinal Flora and Impaired Vitamin A Absorption Reduce Ovarian Function in Mice

Changes in the composition and ratio of the flora during colitis have been found to potentially affect ovarian function through nutrient absorption. However, the mechanisms have not been fully explored. To investigate whether colitis-induced dysbacteriosis of the intestinal flora affects ovarian function, mice were given dextran sodium sulfate (DSS) through drinking water. High-throughput sequencing technology was used to clarify the composition and proportion of bacterial flora as well as gene expression changes in the colon. Changes in follicle type, number, and hormone secretion in the ovary were detected. The results showed that 2.5% DSS could induce severe colitis symptoms, including increased inflammatory cell infiltration, severe damage to the crypt, and high expression of inflammatory factors. Moreover, vitamin A synthesis metabolism-related genes Rdh10, Aldh1a1, Cyp26a1, Cyp26b1, and Rarβ were significantly decreased, as well as the levels of the steroid hormone synthase-related proteins STAR and CYP11A1. The levels of estradiol, progesterone, and Anti-Mullerian hormone as well as the quality of oocytes decreased significantly. The significantly changed abundances of Alistipes, Helicobacter, Bacteroides, and some other flora had potentially important roles. DSS-induced colitis and impaired vitamin A absorption reduced ovarian function.

Authentication, chemical profiles analysis, and quality evaluation of corn silk via DNA barcoding and UPLC-LTQ/Orbitrap MS chemical profiling

Corn silk is commonly consumed in teas, food ingredients, and herbal medicines. Several varieties of corn silk are grown in different habitats in China. However, as information regarding their phytochemistry and genetic diversity is limited, their medicinal potential has not been utilized thoroughly. Thus, we aimed to use a combination of DNA barcoding based on specific primer ITSC sequences and ultra-performance liquid chromatography coupled with linear trap quadrupole-Orbitrap mass spectrometry (UPLC-LTQ/Orbitrap MS) approach for identifying and evaluating corn silk. ITSC barcoding helped us to identify that 52 samples could be classified into 7 groups of corn silk varieties, but the widely used nrITS and psbA-trnH barcodes failed to identify these varieties. UPLC-LTQ/Orbitrap MS was used to study the components in alcohol extracts derived from different corn silk varieties, and the detected chemical components were analyzed via bioinformatics techniques. We proposed 199 components using untargeted UPLC-LTQ/Orbitrap MS-based metabolomics analysis and identified 67 components. PCA and OPLS-DA analysis revealed two distinct chemotypes by selecting 27 components that could act as difference indicators. KEGG analysis showed that the 199 components were enriched in 12 metabolic pathways. The results showed that corn silk is rich in many types of chemicals and DNA barcoding is better than UPLC-LTQ/Orbitrap MS in distinguishing the differences between different varieties of corn silk. Our findings provide new insights into the chemical and molecular characteristics of different varieties of corn silk, which play a crucial role in the utilization of corn silk resources.

Distinctive anti-inflammatory effects of resveratrol, dihydroresveratrol, and 3-(4-hydroxyphenyl)-propionic acid on DSS-induced colitis in pseudo-germ-free mice

Resveratrol is a dietary polyphenol that interacts with gut microbiota to possess various biological activities. To identify the microbial metabolites of resveratrol, fresh feces from 12 volunteers were cultured in vitro. Their urine samples were collected after taking a commercial capsule containing 600 mg of resveratrol. Metabolites were characterized and quantified by UPLC-Q-Exactive plus orbitrap MS/MS. The results showed that dihydroresveratrol, 3-(4-hydroxyphenyl)-propionic acid, and lunularin were the major microbial metabolites of RSV with interindividual differences. 3-(4-Hydroxyphenyl)-propionic acid significantly attenuated the inflammatory response of LPS-treated RAW264.7 cells and DSS-induced colitis in antibiotics-treated pseudo-germ-free mice by regulating MAPK and NF-κB pathways. In contrast, dihydroresveratrol did not exhibit significant anti-inflammatory effects, and lunularin exhibited pro-inflammatory effects in cells. This study may help to better understand the health effects of resveratrol and its microbial metabolites.

Jiedu Yizhi Formula Improves Cognitive Function by Regulating the Gut Dysbiosis and TLR4/NF-κB Signaling Pathway

OBJECTIVE

The objective of this study was to explore the neuroprotective mechanism of JDYZF in treating AD from the perspective of inflammation and intestinal microflora.

METHODS

A total of 24 APP/PS1 mice were randomly divided into four groups: model (n = 6), JDYZF low-dose (n = 6), JDYZF high-dose (n = 6), and positive drug (n = 6), six C57 mice were used as the control group. The body weights and diets of all mice were examined daily. After 8 weeks of administration, the learning and memory of mice were evaluated by the Morris water maze test. The histopathological changes of hippocampus, liver and kidney in mice were observed by HE staining after being euthanized. The expression of p-tau in hippocampus tissue was detected by immunohistochemistry. After that, 16S rDNA sequencing was used to investigate the relationship between JDYZF and intestinal microbiota. Finally, a comparison of TLR4, p65, p-p65, iκB, p-iκB, and IL-1β protein expression in the hippocampus tissue of mice in each group was measured by Western blot.

RESULTS

The results showed that APP/PS1 mice taking JDYZF orally were generally in good condition. Compared with the control group, JDYZF significantly improved learning and memory ability in ethology. Histology showed that JDYZF improved the hippocampal structure of mice and inhibited the deposition of p-tau. JDYZF treatment could regulate the gut microbiota of APP/PS1 mice by increasing the richness of Lachnospiraceae, Ruminococcaceae, and Actinobacteria and reducing that of Alistipes and Muribaculaceae. It also significantly inhibited the activation of the TLR4/NF-κB signaling pathway in the brain. In addition, no obvious toxic reactions were found in the liver and kidney of APP/PS1 mice after taking JDYZF for 8 weeks.

CONCLUSION

The findings revealed that JDYZF improved cognitive ability and alleviated the TLR4/NF-κB signaling pathway in APP/PS1 mice, and the modulating the gut microbiota presented here may help illuminate its activation mechanism.

Flos Puerariae-Semen Hoveniae medicinal pair extract ameliorates DSS-induced inflammatory bowel disease through regulating MAPK signaling and modulating gut microbiota composition

Background: Inflammatory bowel disease (IBD) is a global gastrointestinal disease characterized by relapsing and remitting inflammatory conditions. Flos Puerariae (the flower of Pueraria lobata [Willd.] Ohwi and P. thomsonii Benth.) and Hovenia dulcis Thunb. (Rhamnaceae) are traditional Chinese medicines. This medicinal pair has been used to treat various diseases due to its excellent anti-oxidant and anti-inflammatory activity. However, the effects of extracts from these plants on dextran sulfate sodium (DSS)-induced colitis have not been investigated; further study is needed to improve the understanding of their mechanisms of action and potential applications. Methods: The chemical constitution of extracts from Flos Puerariae and Semen Hoveniae (PHE) was analyzed using UPLC-LTQ-Orbitrap-MS/MS. The protective effects of PHE on mice with DSS-induced colitis were evaluated through assessment of body weight loss, disease activity index (DAI) score, colon length shortening, and pathological changes. The levels of inflammatory cytokines were determined by ELISA and RT-qPCR. Biomarkers of oxidative stress (ROS, CAT, SOD, MDA, and T-AOC) were analyzed using biochemical kits. The expression of MAPK proteins was determined by Western blotting analysis. Gut microbiota were analyzed via 16S rRNA sequencing. Results: Chemical composition analysis indicated that PHE contains various bioactive compounds, including puerarin, kakkalide, tectoridin, and genistin. The findings from this study suggest that PHE could effectively modulate histopathological score, inflammatory cell infiltration, and inflammatory factor secretion. Notably, PHE ameliorated oxidative stress by inhibiting activation of the MAPK pathway, leading to decreased inflammatory mediators and restored antioxidant enzyme activity. Furthermore, PHE treatment regulated the composition of the gut microbiota by increasing the abundance of benign bacteria, such as Akkermansia, and reducing the abundance of harmful bacteria, such as Proteobacteria. Conclusion: The findings from this study demonstrate the mechanism underlying the amelioration of DSS-induced intestinal oxidative stress by PHE and its positive impact on the restoration of the composition of gut microbiota.

Rice Protein Peptides Alleviate Dextran Sulfate Sodium-Induced Colitis via the Keap1-Nrf2 Signaling Pathway and Regulating Gut Microbiota

Inflammatory bowel disease (IBD), with increasing incidence, causes a range of gastrointestinal symptoms and brings distress and impact on the health and lives of patients. The aim of this study was to explore the protective effects of industrially produced rice protein peptides (RPP) on dextran sulfate sodium (DSS)-induced acute colitis in mice and the potential mechanisms. The results showed that RPP treatment alleviated the symptoms of colitis in mice, including weight loss, colon shortening, and injury, decreased the level of disease activity index (DAI), regulated the balance of inflammatory factors and oxidation, activated Kelch-like ECH-associating protein 1 (Keap1)-nuclear factor E2-related factor 2 (Nrf2) signaling pathway, regulated the expression of related antioxidant proteases, and promoted the expression of intestinal tight junction proteins. In addition, RPP maintained intestinal mucosal barrier function and alleviated acute colitis caused by DSS treatment in mice by increasing the value of F/B, increasing the relative abundance of beneficial bacteria such as Akkermansia, and regulating the level of short-chain fatty acids. In conclusion, RPP alleviated colitis symptoms through the Keap1-Nrf2 signaling pathway and regulating gut microbiota, which had the potential as dietary supplements or functional foods.

Analysis of the shape characteristics and nutritional components of Akebia trifoliata in Qinba Mountains

Akebia trifoliata (A. trifoliata) is a widely distributed wild vine that has attracted much attention in recent years due to the edible fruit of food and medicinal value. In this paper, the fruits of A. trifoliata, which are derived from Qinling Mountains (12 genotypes) and Bashan Mountains (4 genotypes) and have been artificially domesticated and cultivated for many years, are taken as the research object to study the fruit characteristics and pulp components of 16 genotypes of A. trifoliata. The results show that the pulp of the 16 genotypes contain a variety of nutrients, among which the average contents of total sugar, total acid, vitamin C, soluble solids and starch are 14.68g/100g, 0.14g/100g, 26.40mg/100g, 17.95% and 5.29g/100g. The fruit contains 17 amino acids, including 7 essential amino acids and 4 organic acids. The latter refers to malic acid, lactic acid, citric acid and fumaric acid, the average contents of which are 1.03g/kg, 3.38g/kg, 0.33g/kg and 0.0149g/kg. Besides, 8 mineral elements in the fruit include 4 macro elements and 4 micro elements. The average contents of the former are potassium (1.83g/kg), calcium (0.23g/kg), phosphorus (0.28g/kg) and magnesium (0.21g/kg), and the average contents of the latter are iron (2.29mg/kg), zinc (2.23mg/kg), copper (1.37mg/kg) and manganese (5.52mg/kg). During the ripening process of A. trifoliata fruit (using HY-9 as the material), the main nutrients in the pulp such as total sugar, soluble solids, starch, amino acids and various mineral elements reach the maximum in stage 3, indicating that stage 3 is the best edible period of A. trifoliata fruit. Through the assignment analysis and comprehensive evaluation of 9 quality indicators (3 apparent characters and 6 main chemical components) of the fruits of the 16 A. trifoliata genotypes from Qinba Mountains, HY-1, HY-2 and HY-9 were finally screened out as the three superior genotypes. This study aims to provide reference for the development and utilization of A. trifoliata wild germplasm resources and the selection of new varieties.

Glycerol monolaurate ameliorates DSS-induced acute colitis by inhibiting infiltration of Th17, neutrophils, macrophages and altering the gut microbiota

Background and aims

Inflammatory bowel disease (IBD) places a heavy medical burden on countries and families due to repeated and prolonged attacks, and the incidence and prevalence of IBD are increasing worldwide. Therefore, finding an effective treatment is a matter of great urgency. Glycerol monolaurate (GML), which has a twelve-carbon chain, is a compound naturally found in human breast milk. Some studies have shown that GML has antibacterial and anti-inflammatory effects. However, the specific mechanism of action remains unclear.

Methods

Acute colitis was established in mice using 3% DSS, and glycerol monolaurate (500 mg·kg-¹) was administered for two weeks. QPCR and western blotting were performed to examine the inflammatory status. Mice described were subjected to flow cytometry analysis for immune cell activation.

Results

GML treated alleviated macroscopic symptoms such as shortened colons, increased spleen weight, and caused weight loss in mice with DSS-induced colitis. In addition, GML decreased the expression of pro-inflammatory factors (NF-α, IL-1β and IL-1α) and increased the expression of anti-inflammatory factors (IL-10 and TGF-β). GML inhibited the activation of the MAPK and NF-κB signalling pathways, improved tissue damage, and increased the expression of intestinal tight junction proteins. In addition, LPMCs extracted from intestinal tissue via flow cytometry showed that GML treatment led to a decrease of Th17 cells, Neutrophils and Macrophages. 16S rDNA sequencing showed that GML increased the abundance of commensal bacterium such as Akkermansia and Lactobacillus murinus.

Conclusions

We showed that oral administration of GML ameliorated DSS-induced colitis by inhibiting infiltration of Th17 cells, Neutrophils, and Macrophages, protecting the intestinal mucosal barrier and altered the abundance of commensal bacterium. This study provides new insights into the biological function and therapeutic potential of GML in the treatment of IBD.

Metabolomic Profile and Antibacterial Bioactivity of Akebia trifoliata (Thunb.) Koidz Pericarp Extract

Akebia trifoliata (A. trifoliata) is a significant medicinal and edible fruit crop and has some important bioactivities. However, there are few studies on the bacteriostatic activity of A. trifoliata, and the underlying mechanism of A. trifoliata for antibacterial activity is still unknown. Therefore, the bacteriostatic activity and antibacterial mechanism of A. trifoliata were investigated by a combination of chemical assays, using the UHPLC-TOF-MS/MS technique. The results indicated that alkaloids, triterpenoids, and flavonoids are the major secondary bioactive compounds in A. trifoliata that play a crucial role in antibacterial activity. We found that EEPA exhibited both bacteriostatic and bactericidal effects against all Gram-positive and Gram-negative bacteria tested, with IZDs ranging from 13.80 ± 0.79 to 17.00 ± 0.58 mm. Significant differences in terms of sensitivity between Gram-positive and Gram-negative bacteria were not observed. In contrast, both antibiotics (kanamycin sulfate and ampicillin sodium salt) exhibited much better antimicrobial activity against Gram-positive bacteria than Gram-negative bacteria. In addition, the primary antimicrobial mechanism was that EEPA increased cellular content leakage, altered the cell morphology, and destroyed the internal cell structure. Meanwhile, MA, UA, and OA, as the common triterpenoid components existing in plants, were used to analyze the relationships between the structures and the antimicrobial activities among homologous compounds, to determine the key functional group that plays an antibacterial role in MA, UA, and OA. As result, it was found that both the hydroxide and methyl groups present are important for their antibacterial activity. These findings suggested that EEPA exerted significant antimicrobial activity against S. aureus, E. coli, B. subtilis, and P. aeruginosa and might be a potential natural antibacterial.

Industrially Produced Rice Protein Ameliorates Dextran Sulfate Sodium-Induced Colitis via Protecting the Intestinal Barrier, Mitigating Oxidative Stress, and Regulating Gut Microbiota

Inflammatory bowel disease (IBD) poses a threat to health and compromises the immune system and gut microflora. The present study aimed to explore the effects of rice protein (RP) purified from rice dregs (RD) on acute colitis induced by dextran sulfate sodium (DSS) and the underlying mechanisms. Results showed that RP treatment could alleviate the loss of body weight, colon shortening and injury, and the level of disease activity index, repair colonic function (claudin-1, ZO-1 and occludin), regulate inflammatory factors, and restore oxidative balance (malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), and total antioxidant capability (T-AOC)) in mice. Also, RP treatment could activate the Kelch-like ECH-associating protein 1 (Keap1)-nuclear factor E2-related factor 2 (Nrf2) signaling pathway, mediate the expression of downstream antioxidant protease (NQO-1, HO-1, and Gclc), regulate gut microbiota by enhancing the relative abundance of Akkermansia and increasing the value of F/B, and adjust short-chain fatty acid levels to alleviate DSS-induced colitis in mice. Thus, RP may be an effective therapeutic dietary resource for ulcerative colitis.

Optimization of Flash Extraction of Akebia trifoliata Seed Oil by the Box-Behnken Response Surface Methodology and Comparison of Oil Yields from Different Origins

The aim was to optimize the extraction process of Akebia trifoliata seed oil. Using Akebia trifoliata seed as raw material, the oil extraction rate was used as index. The effect of flash extraction on the yield of Akebia trifoliata seed oil was investigated. Taking the liquid-material ratio, extraction voltage, and extraction time as the investigation factors and the oil extraction rate of Akebia trifoliata seed as the response value and on the basis of the single-factor test, the extraction process of Akebia trifoliata seed oil was optimized by the Box-Behnken response surface method. The oil yields of Akebia trifoliata seeds from different origins in China were compared. The experimental results showed that the optimum technological conditions for flash extraction of Akebia trifoliata seed oil were as follows: liquid-material ratio, 12 : 1; extraction voltage, 150 V; extraction time, 90 s; and oil yield of Akebia trifoliata seed, 19.83%. For comparison, it is found that the oil yield of Akebia trifoliata seed produced in Qujing of Yunnan is relatively the highest, followed by Tongren of Guizhou and Zhangjiajie of Hunan; the oil yield of Akebia trifoliata seed produced in Shimian of Sichuan is the lowest. The flash extraction process of Akebia trifoliata seed oil is reasonable, and the oil yield of Akebia trifoliata seed produced in Qujing of Yunnan, China, is relatively the highest. It provides a theoretical and experimental reference for the research and development of Akebia trifoliata seed oil.

Polyphenol Content of Green Pea (Pisum sativum L.) Hull under In Vitro Digestion and Effects of Digestive Products on Anti-Inflammatory Activity and Intestinal Barrier in the Caco-2/Raw264.7 Coculture Model

Green pea hulls are a byproduct of the processing of green pea and are rich in phenolic substances. In the present study, in vitro digestion, human colonic adenocarcinoma cell line (Caco-2) monolayer, and the Caco-2/macrophage cell lines of the murine origin (Raw264.7) coculture model were established to investigate the release of polyphenols, absorption, and transport of digestive products and their effects on inflammation and intestinal barrier. During the digestive process, polyphenols were constantly released from the pea hulls, reaching the maximum amount in the small intestine (total phenolic content (TPC): 5.41 ± 0.04 mg gallic acid (GAE)/g dry weight (DW)), and the digestive products (800 μg/mL) could reduce the secretion of NO (50.9%), IL-6 (50.6%), and TNF-α (24.6%) and inhibit the mRNA expression of cyclooxygenase-2 (COX-2) (37.2%) and inducible nitric oxide synthase (iNOS) (91.1%) compared with the lipopolysaccharide (LPS) group. A total of 12 phenolic components were quantified by ultraperformance liquid chromatography-linear ion trap orbitrap tandem mass spectrometry (UHPLC-LTQ-OrbiTrap-MS) technology. Kaempferol trihexoside in digestive products could be absorbed and transported (1.25 ± 0.13 ng quercetin/mL). The digestive products could promote the expression of claudin-1 (210.8%), occludin (64.9%), and zonulin occludin-1 (ZO-1) (52.0%) compared with the LPS group and exert anti-inflammatory effects after being absorbed. The results indicated that pea hull polyphenols could be continuously released and absorbed to play a positive role in protecting the intestinal barrier and anti-inflammatory activity.

Regulating the Imbalance of Gut Microbiota by Smilax china L. Polyphenols to Alleviate Dextran Sulfate Sodium-induced Inflammatory Bowel Diseases

Smilax china L. is used not only as a kind of traditional Chinese herbal medicinal ingredients with various pharmacological properties, but also as food in certain parts of China. However, it is by far still unclear whether Smilax china L. polyphenols (SCP), as important bioactive constituents in Smilax china L., have effects on inflammatory bowel diseases (IBD). This study investigated the impact of SCP on the dextran sulfate sodium (DSS)-induced IBD and gut microbiota in mice. SCP treatments ameliorated typical symptoms of IBD as what was reflected through suppressing body weight loss, colonic shortening, intestinal barrier damage, and increasing intestinal disease activity index. SCP treatments simultaneously decreased the release of proinflammatory cytokines and oxidative stress, as well as promoted the release of anti-inflammatory factors. Furthermore, SCP ameliorated the ecological imbalance of gut microbiota and regulated the key bacteria associated with IBD (including Akkermansiaceae, Ruminococcaceae, Acidaminococcaceae, Muribaculaceae, and Anaeroplasmataceae). In general, SCP may improve DSS-induced IBD in mice by regulating inflammatory factors, inhibiting oxidative stress, reducing intestinal tissue damage, and regulating the ecological imbalance of intestinal microbiota. Thus, SCP might serve as a potential therapeutic agent against the inflammation-driven diseases.

Effects of climate change on the distribution of wild Akebia trifoliata

Understanding the impacts and constraints of climate change on the geographical distribution of wild Akebia trifoliata is crucial for its sustainable management and economic development as a medicinal material or fruit. In this study, according to the first-hand information obtained from field investigation, the distribution and response to climate change of A. trifoliata were studied by the MaxEnt model and ArcGIS. The genetic diversity and population structure of 21 natural populations of A. trifoliata were studied by simple sequence repeat (SSR) markers. The results showed that the most important bioclimatic variable limiting the distribution of A. trifoliata was the Mean Temperature of Coldest Quarter (bio11). Under the scenarios SSP1-2.6 and SSP2-4.5, the suitable area of A. trifoliata in the world will remain stable, and the suitable area will increase significantly under the scenarios of SSP3-7.0 and SSP5-8.5. Under the current climate scenario, the suitable growth regions of A. trifoliata in China were 79.9-122.7°E and 21.5-37.5°N. Under the four emission scenarios in the future, the geometric center of the suitable distribution regions of Akebia trifoliata in China will move to the north. The clustering results of 21 populations of A. trifoliata analyzed by SSR markers showed that they had a trend of evolution from south to north.

Painong-San extract alleviates dextran sulfate sodium-induced colitis in mice by modulating gut microbiota, restoring intestinal barrier function and attenuating TLR4/NF-κB signaling cascades

The intestinal barrier dysfunction and the gut microbiota dysbiosis with excessive progress of inflammation contribute to the occurrence and acceleration of ulcerative colitis (UC). Painong Powder, a traditional Chinese medicine prescription, consists of Aurantii Fructus Immaturus, Paeoniae Radix Alba and Platycodonis Radix, which has been found to defend against colitis, but it is unclear whether its role in preventing UC is related to gut microbiota. This study aims to evaluate the effects of Painong-San extract (PNS) on UC and reveals the mechanisms related to gut microbiota. Firstly, a total of 125 chemical compounds, including 42 flavonoids, 29 triterpenoids, 21 monoterpenoids, 11 polyphenols, 6 limonoids, 5 alkaloids, 4 coumarins and 7 other compounds, were identified from PNS using ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. Then, the results in vivo studies demonstrated that PNS treatment reduced the weight loss and the disease activity index, prevented colon shortening and alleviated colonic tissue damage in dextran sulfate sodium (DSS)-induced colitis mice. The intestinal barrier damage was repaired after PNS administration through promoting the expression of tight junction proteins (claudin-1, occludin and zonula occludens-1). More interestingly, PNS regulated gut microbiota dysbiosis, suppressed the overgrowth of conditional pathogenic gut bacteria, such as Oscillospiraceae and Helicobacter, while the probiotic gut microbiota like Romboutsia, Lactobacillus, Bifidobacterium and Akkermansia were increased. Furthermore, PNS remarkably ameliorated colonic inflammatory response through inhibiting intestinal TLR4/NF-κB signaling pathway by down-regulating the protein expressions of TLR4, MyD88, p-NF-κB p65 and p-IκBα. Taken together, PNS effectively improved DSS-induced colitis through the modulation of gut microbiota, restoration of intestinal barrier function and attenuation of TLR4/NF-κB signaling cascades, which may provide a new explanation of the mechanisms of PNS against UC.

Green Pea (Pisum sativum L.) Hull Polyphenol Extracts Ameliorate DSS-Induced Colitis through Keap1/Nrf2 Pathway and Gut Microbiota Modulation

As a processing by-product, green pea hull (GPH) was found to be rich in phenolic components in our previous studies. In this study, UHPLC-LTQ-OrbiTrap-MS (Ultra performance liquid chromatography-linear ion trap orbitrap tandem mass spectrometry) technique was used to quantify polyphenols, and DSS (sodium dextran sulfate)-induced colitis mouse model was established to explore the effect of GPH extracts on colitis. The results showed that quercetin and its derivatives, kaempferol trihexanside and catechin and its derivatives were the main phenolic substances in the extract, reaching 2836.57, 1482.00 and 1339.91 µg quercetin/g GPH extract, respectively; GPH extracts can improved inflammatory status, repaired colonic function, regulated inflammatory factors, and restored oxidative balance in mice. Further, GPH extracts can activate Keap1-Nrf2-ARE signaling pathway, regulate downstream antioxidant protease and gut microbiota by increasing F/B value and promoting the growth of Lactobacillaceae and Lachnospiraceae, and improve the level of SCFAs (short-chain fatty acids) to relieve DSS-induced colitis in mice. Therefore, GPH may be a promising dietary resource for the treatment of ulcerative colitis.

The preventive effect and underlying mechanism of Rhus chinensis Mill. fruits on dextran sulphate sodium-induced ulcerative colitis in mice

The purpose of this research was to explore the preventive effect of an 80% ethanol extract of Rhus chinensis Mill. fruits on dextran sulfate sodium (DSS)-induced colitis in mice and to elucidate the underlying molecular mechanisms of this effect. The results indicated that the extract, especially when administered at a high dose, could dramatically decrease the disease activity index, maintain normal spleen conditions, and improve colonic histopathology and length in the DSS-induced mice. In addition, extract administration could significantly suppress the levels of malondialdehyde, myeloperoxidase, tumor necrosis factor-α, interleukin-1β, and interleukin-6 and enhance superoxide dismutase and glutathione levels. The extract obviously protected intestinal barrier integrity by improving Occludin, ZO-1 and Claudin-1 expression levels. Western blot and immunohistochemistry analyses further indicated that the preventive effect of the phenol-rich extract on DSS-induced colitis might be achieved through the up-regulation of the expression of several pivotal oxidative stress-associated proteins, namely Nrf2, NQO1 and HO-1, and the down-regulation of the expression of several pivotal inflammation-associated proteins, namely p-NF-κB, p-IκB, COX-2, iNOS, p-P38, p-Erk1/2, and p-JNK. Therefore, R. chinensis fruits extract possesses the capability to prevent DSS-induced ulcerative colitis in mice and could be utilized as a natural substance in the exploitation of functional foods as an adjuvant dietary therapy for preventing and/or alleviating inflammatory bowel disease.

Dietary Tangeretin Alleviated Dextran Sulfate Sodium-Induced Colitis in Mice via Inhibiting Inflammatory Response, Restoring Intestinal Barrier Function, and Modulating Gut Microbiota

In this study, the preventive effect of tangeretin (TAN), a natural flavonoid derivative from citrus fruits, on the dextran sulfate sodium (DSS)-induced colitis in mice was evaluated. Our results showed that dietary TAN (0.04% and 0.08% w/w in the diet) significantly reduced the severity of colitis caused by DSS treatment in mice, evidenced by the increased colon length, the reduced disease activity index, and the attenuated colonic tissue damages. Moreover, dietary TAN inhibited the inflammatory response via down-regulating the overexpression of colonic inflammatory cytokines. Immunohistochemical analysis revealed that the intestinal barrier function was restored by TAN through enhancing claudin-1 and ZO-1 expressions. Additionally, dietary TAN modulated gut microbiota in colitic mice via enhancing gut microbiota diversity, ascending the level of beneficial bacteria, e.g., Lachnospiraceae and Lactobacillaceae, and descending the level of harmful bacteria, e.g., Enterobacteriaceae and Alistipes. Besides, dietary TAN promoted short-chain fatty acids production in DSS-treated mice. Altogether, these findings provided scientific evidence for the rational utilization of TAN as a preventive agent against colonic inflammation and related diseases.

Influences of Microwave-Assisted Extraction Parameters on Antioxidant Activity of the Extract from Akebia trifoliata Peels

Akebia trifoliata is a fruit with rich nutritional properties, and its peel is produced as a by-product. In this research, we investigated the influences of microwave-assisted extraction parameters on antioxidant activity of the extract from Akebia trifoliata peels, and the ferric-reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) as well as total phenolic contents (TPC) were used to optimize extraction parameters. The influences of ethanol concentration, microwave power and solvent-to-material ratio, as well as extraction temperature and time on TPC, FRAP and TEAC values, were assessed using single-factor tests. Three parameters with obvious effects on antioxidant capacity were selected to further investigate their interactions by response surface methodology. The optimal extraction parameters of natural antioxidants from Akebia trifoliata peels were ethanol concentration, 49.61% (v/v); solvent-to-material ratio, 32.59:1 mL/g; extraction time, 39.31 min; microwave power, 500 W; and extraction temperature, 50 °C. Under optimal conditions, the FRAP, TEAC and TPC values of Akebia trifoliata peel extracts were 351.86 ± 9.47 µM Fe(II)/g dry weight (DW), 191.12 ± 3.53 µM Trolox/g DW and 32.67 ± 0.90 mg gallic acid equivalent (GAE)/g DW, respectively. Furthermore, the main bioactive compounds (chlorogenic acid, rutin and ellagic acid) in the extract were determined by high-performance liquid chromatography. The results are useful for the full utilization of the by-product from Akebia trifoliate fruit.