Intestinal microbes derived butyrate is related to the immunomodulatory activities of Dendrobium officinale polysaccharide

The comprehensive analysis of gut microbiome and spleen transcriptome revealed the immunomodulatory mechanism of Dendrobium officinale leaf polysaccharide on immunosuppressed mice

In recent years, the immunomodulatory efficacy of Dendrobium officinale leaf polysaccharide (DOLP) has attracted much attention, but its potential immunomodulatory mechanism remains unclear. Therefore, we investigated the molecular mechanism of DOLP to ameliorate cyclophosphamide-induced immunosuppressed mice based on transcriptome profiling technology. The results indicated that DOLP significantly mitigated damage to immune organs, regulated the expression levels of inflammatory factors and immunoglobulins, and restored the balance of gut microbiota. Furthermore, it modulated metabolic pathways associated with the immune system, including antigen processing and presentation, hematopoietic cell line development, and natural killer cell-mediated cytotoxicity. DOLP might promote host hematopoietic function to enhance immune cell proliferation and differentiation by up-regulating Cd19, Cr2 and Il7r but down-regulating Dntt. DOLP also up-regulated the expression of MHC-1 (Gm11127, H2-K1, H2-Q10, H2-Q6, and H2-Q7), thus promoting antigen recognition by NK cells to enhance the innate immunity and helping T cells to deliver antigen and secrete immune factors so that enhancing the adaptive immunity.

Interplay between traditional Chinese medicine polysaccharides and gut microbiota: The elusive "polysaccharides-bond-bacteria-enzyme" equation

Polysaccharides are one of the most important components of traditional Chinese medicine (TCM) and have been extensively studied for their immunomodulatory properties. The functions and effects of TCM polysaccharides are closely related to the gut microbiota, making the study of their interaction a hot topic in the field of TCM metabolism. This review follows two main inquiries: first, how the gut microbiota breaks down TCM polysaccharides to produce bioactive metabolites; and second, how TCM polysaccharides reshape the gut microbiota as a carbon source. Understanding the interaction mechanism involves a challenging equation of the structural association of TCM polysaccharides with the metabolic activities of the microbiota. This review has meticulously searched, partially organized literature spanning the past decade, that delves into the interaction mechanism between TCM polysaccharides and gut microbiota. It also gives an overview of the complex factors of the elusive "polysaccharides-bond-bacteria-enzyme" equation: the complexity of polysaccharide structures, the diversity of glycosidic bond types, the communal nature of metabolizing microbiota, the enzymes involved in functional degradation by microbiota, and the hierarchical roles of polysaccharide utilization locus and gram-positive PULs. Finally, this review aims to facilitate discussion among peers in the field of TCM microbiota and offers prospects for research in related fields, paving the way for pharmacological studies on TCM polysaccharides and gut microbiota therapeutics, and providing a reference point for further clinical research.

Multi-omics analysis reveals the impact of gut microbiota on antipsychotic-induced weight gain in schizophrenia

Emerging evidence indicates that gut microbial dysbiosis is associated with the development of antipsychotic-induced weight gain in schizophrenia (SZ). However, the exact taxonomic composition and functionality that constitute the "obesogenic" microbial profile remain elusive. Our retrospective survey identified two groups of the SZ population separated by BMI, with 1/3 of patients developing overweight/obesity after chronic antipsychotic treatment. Based on multi-omics analysis, we observed altered gut microbiota in SZ patients with overweight/obesity, characterized by a reduction in several beneficial bacteria genera, including Bacteroides, Parabacteroides, Akkermansia, and Clostridium. This microbial dysbiosis was accompanied by disrupted energy expenditure and nutritional metabolism, worsened metabolic indices, and reduced levels of beneficial metabolites, e.g. indole-3-carboxylic acid and propionic acid. Moreover, leveraging data from first-episode drug-naïve schizophrenia (FSZ) patients at one-month and one-year follow-up, both artificial neural network and random forest classifier-based prediction models demonstrated a strong ability of microbial profiles to predict antipsychotic-induced weight gain. Importantly, FSZ patients with higher relative abundance of Parabacteria distasonis were less susceptible to antipsychotic-induced weight gain. Thus, gut microbiota could serve as a noninvasive approach to predict antipsychotic-induced weight gain, guiding clinical antipsychotics administration and developing novel therapeutic strategies for weight management in SZ.

Intestinal Barrier Dysfunction and Gut Microbiota in Non-Alcoholic Fatty Liver Disease: Assessment, Mechanisms, and Therapeutic Considerations

Non-alcoholic fatty liver disease (NAFLD) is a type of metabolic stress liver injury closely related to insulin resistance (IR) and genetic susceptibility without alcohol consumption, which encompasses a spectrum of liver disorders ranging from simple hepatic lipid accumulation, known as steatosis, to the more severe form of steatohepatitis (NASH). NASH can progress to cirrhosis and hepatocellular carcinoma (HCC), posing significant health risks. As a multisystem disease, NAFLD is closely associated with systemic insulin resistance, central obesity, and metabolic disorders, which contribute to its pathogenesis and the development of extrahepatic complications, such as cardiovascular disease (CVD), type 2 diabetes mellitus, chronic kidney disease, and certain extrahepatic cancers. Recent evidence highlights the indispensable roles of intestinal barrier dysfunction and gut microbiota in the onset and progression of NAFLD/NASH. This review provides a comprehensive insight into the role of intestinal barrier dysfunction and gut microbiota in NAFLD, including intestinal barrier function and assessment, inflammatory factors, TLR4 signaling, and the gut-liver axis. Finally, we conclude with a discussion on the potential therapeutic strategies targeting gut permeability and gut microbiota in individuals with NAFLD/NASH, such as interventions with medications/probiotics, fecal transplantation (FMT), and modifications in lifestyle, including exercise and diet.

Critical review on the research of chemical structure, bioactivities, and mechanism of actions of Dendrobium officinale polysaccharide

Dendrobium officinale (Tie-Pi-Shi-Hu) is a precious traditional Chinese medicine (TCM). The principal active components are polysaccharides (DOP), which have a high potency in therapeutic applications. However, limitations in structure analysis and underlying mechanism investigation impede its further research. This review systemically and critically summarises current understanding in both areas, and points out the influence of starch impurities and the role of gut microbiota in DOP research. As challenges faced in studying natural polysaccharide investigations are common, this review contributes to a broader understanding of polysaccharides beyond DOP.

Effects of almond (Armeniaca Sibirica L. Lam) polysaccharides on gut microbiota and anti-inflammatory effects on LPS-induced RAW264.7 cells

The aim of this study was to investigate the prebiotic properties of the almond polysaccharide AP-1 on intestinal microorganisms by using an in vitro fecal fermentation method and its anti-inflammatory effect on lipopolysaccharide (LPS)-induced RAW264.7 cells. The results showed that during the in vitro fermentation of AP-1, the pH value of the fermentation broth decreased obviously, while the concentration of short-chain fatty acids (SCFAs) increased significantly, especially acetic acid and butyric acid. In genus level, the number of Clostridium and Megamonas increased markedly in the AP-1 group after 24 h of fermentation. After 48 h of fermentation, there was a noticeable increase in the number of beneficial genera Lactobacillaceae and Bifidobacteriaceae, and a considerable decrease in the number of pro-inflammatory genera. In addition, we found that AP-1 had no toxic effect on RAW264.7 cells. In the LPS-induced inflammation model of RAW264.7 cells, AP-1 could effectively inhibit the release of NO, regulate the level of reactive oxides (ROS), and effectively down-regulate the mRNA expression of TNF-α, IL-1β, IL-6 and iNOS. In conclusion, the almond polysaccharide AP-1 may be a functional active substance aimed at promoting intestinal health and exerting anti-inflammatory effects.

In vitro digestion and fecal fermentation of selenocompounds: impact on gut microbiota, antioxidant activity, and short-chain fatty acids

Selenium bioavailability is critically influenced by gut microbiota, yet the interaction dynamics with selenocompounds remain unexplored. Our study found that L-Selenomethionine (SeMet) and Se-(Methyl)seleno-L-cysteine (MeSeCys) maintained stability during in vitro gastrointestinal digestion. In contrast, Selenite and L-Selenocystine (SeCys2) were degraded by approximately 13% and 35%. Intriguingly, gut microflora transformed MeSeCys, SeCys2, and Selenite into SeMet. Moreover, when SeCys2 and Selenite incubated with gut microbiota, they produced red selenium nanoparticles with diameters ranging between 100 and 400 nm and boosted glutathione peroxidase activity. These changes were positively associated with an increased relative abundance of unclassified_g__Blautia (Family Lachnospiraceae), Erysipelotrichaceae_UCG-003 (Family Erysipelatoclostridiaceae), and uncultured_bacterium_g__Subdoligranulum (Family Ruminococcaceae). Our findings implied that differential microbial sensitivities to selenocompounds, potentially attributable to their distinct mechanisms governing selenium uptake, storage, utilization, and excretion.

Raspberry polysaccharides attenuate hepatic inflammation and oxidative stress in diet-induced obese mice by enhancing butyrate-mediated intestinal barrier function

Obesity and associated liver diseases are becoming global public health challenges. Raspberry (Rubus chingii Hu.), as a medicine food homology plant, possesses a series of health-promoting properties, but its protective effect on obesity-related liver injury and the potential mechanisms remain obscure. Herein high-fat diet (HFD)-fed mice were orally treated with raspberry polysaccharides (RCP) for 14 weeks. Treatment with RCP alleviated obesity and associated symptoms including hyperglycemia, hyperlipemia, endotoxemia, as well as hepatic inflammation and oxidant stress in HFD-induced obese mice. RCP restructured the gut microbiota and host metabolism especially by increasing the levels of Dubosiella and its metabolite butyrate. Besides, exogenous butyrate supplementation protected against intestinal barrier disruption, and thereby reduced inflow of lipopolysaccharide and mitigated inflammation and oxidative injury in the liver of obese mice. Therefore, we suggest that RCP can be utilized as a novel prebiotics to improve obesity-induced hepatic oxidative injury by enhancing butyrate-mediated intestinal barrier function.

Preparation, characterization and immune response of chitosan‑gold loaded Myricaria germanica polysaccharide

In this study, a novel nano-drug delivery system (CS-Au NPs) based on gold nanoparticles (Au NPs) and chitosan (CS) that modified Myricaria germanica polysaccharide (MGP) was developed to enhance immune responses. At a MGP to CS Au ratio of 5:1, CS-Au-MGP NPs had a loading capacity of 78.27 %. The structure of CS-Au-MGP NPs were characterized by Transmission electron microscope, TEM-energy dispersive spectroscopy mapping, Fourier transform infrared spectroscopy, X-ray photoelectron spectrometer, particle size and zeta-potential distribution analysis. Under weakly acidic conditions, in vitro CS-Au-MGP NPs release was most effective. In vivo showed that co-immunization with CS-Au-MGP NPs and PCV2 significantly increased the organ index of the thymus, spleen, and liver in mice. Additionally, CS-Au-MGP NPs significantly increased the levels of IgG, IgG1, and IgG2a antibodies, as well as IFN-γ and IL-6 levels. Furthermore, the CS-Au-MGP NPs promoted proliferation of spleen T and B lymphocytes, increased the number of CD3+, CD4+, and CD8+ cells, and increased the CD4+/CD8+ T cell ratio. Meanwhile, CS-Au-MGP NPs remarkably TLR2/IRAK4 pathway activation and mRNA levels of cytokines (IFN-γ and IL-6). These results indicated that CS-Au-MGP NPs could enhance the immune activity, and it could be potentially used as an MGP delivery system for the induction of strong immune responses.

Dietary supplementation of ark clams protects gut health and modifies gut microbiota in d-galactose-induced aging rats

BACKGROUND

Ark clams, a seafood abundant in various nutrients, are widely consumed worldwide. This study aimed to investigate the protective benefits of two common ark clams in Korea, Scapharca subcrenata (SS) and Tegillarca granosa (TG), on gut health in d-galactose (d-gal)-induced aging rats.

RESULTS

Thirty-two Wistar rats (11 weeks old) were randomly allocated into four groups: a CON group (normal diet + saline intraperitoneal (i.p.) injection), a CD group (normal diet + d-gal i.p. injection), an SS group (normal diet with 5% SS supplementation + d-gal i.p. injection), and a TG group (normal diet with 5% TG supplementation + d-gal i.p. injection). After 12 weeks of treatment, histopathological results showed that gut barrier damage was alleviated in rats of the SS and TG groups, as evidenced by increases in mucus layer thickness and goblet cell numbers. Meanwhile, the two groups supplemented with ark clams showed an evident reduction in oxidative stress biomarkers (malondialdehyde and protein carbonyl content levels in the colon) and an increase in the immune-related factor (immunoglobulin A level in the plasma) in rats. The 16S ribosomal RNA analysis revealed that SS and TG ark clams significantly increased the proliferations of Bacteroidetes at the phylum level and Parabacteroides at the genus level. Additionally, the levels of the three main short-chain fatty acids in the cecal contents were also significantly increased in the SS and TG groups.

CONCLUSION

Our results indicated a potent preventive effect of SS and TG ark clams on d-gal-induced gut injury, suggesting that ark clams may be a promising dietary component for intervening in aging. © 2023 Society of Chemical Industry.

Zanthoxylum bungeanum amides ameliorates nonalcoholic fatty liver via regulating gut microbiota and activating AMPK/Nrf2 signaling

ETHNOPHARMACOLOGICAL RELEVANCE

Zanthoxylum bungeanum Maxim. (Rutaceae) is a known herbal medicine with various bioactivities, including anti-obesity, lipid-lowering, learning & memory improving and anti-diabetes, and amides in Z. bungeanum (AZB) are considered as the major active agents for its bioactivities.

AIM OF THE STUDY

This research was carried out to uncover the anti-NAFL effect of AZB and its corresponding molecular mechanisms.

METHODS

The central composite design-response surface methodology (CCD-RSM) was utilized to optimize the AZB extraction process, and the anti-NAFL effect of AZB was investigated on high fat diet (HFD) fed mice (HFD mice). The levels of ROS in liver tissues were determined using laser confocal microscopy with DCFH-DA probe staining, and anti-enzymes (such as HO-1, SOD, CAT & GSH-PX) and MDA in liver tissues were measured using commercial detecting kits. GC-MS was used to determine the short-chain fatty acids (SCFAs) contents in feces and blood of mice. 16S high-throughput sequencing, western blotting (WB) assay and immunofluorescence (IF) were used to explore the intestinal flora changes in mice and the potential mechanisms of AZB for treatment of NAFL.

RESULTS

Our results showed AZB reduced body weight, alleviated liver pathological changes, reduced fat accumulation, and improved oxidative stress in HFD mice. In addition, we also found AZB improved OGTT and ITT, reduced TG, TC, LDL-C, whereas increased HDL-C in HFD mice. AZB increased total number of the species and interspecies kinship of gut microbiota and reduced the richness and diversity of gut microbiota in HFD mice. Moreover, AZB decreased the ratio of Firmicutes/Bacteroidota, whereas increased the abundance of Allobaculum, Bacteroides and Dubosiella in feces of HFD-fed mice. Furthermore, AZB increased the production of SCFAs, and up-regulated the phosphorylation of AMPK and increased the nuclear transcription of Nrf2 in liver of HFD mice.

CONCLUSION

Collectively, our results suggested AZB can improve NAFL, which could reduce body weight, reverse liver lesions and fat accumulation, improve oxidative stress in liver tissues of HFD mice. Furthermore, the mechanisms are related to increase of the abundance of high-producing bacteria for SCFAs (e.g. Allobaculum, Bacteroides and Dubosiella) to activate AMPK/Nrf2 signaling.

Dendrobium offificinale polysaccharides prevents glucocorticoids-induced osteoporosis by destabilizing KEAP1-NRF2 interaction

Glucocorticoid-induced osteoporosis (GIOP) represents the foremost cause of secondary osteoporosis and fragility fractures. Novel therapeutic strategies for GIOP are needed, with improved safety profiles and reduced costs compared to current options. Dendrobium officinale (D. officinale) is a traditional Chinese medicine that has been reported to have beneficial effects on bone metabolism. Here, we sought to investigate the impacts of D. officinale polysaccharides (DOP), the main active constituents of D. officinale, on GIOP in vivo models and dexamethasone (DEX)-treated osteoblast lineage cells. We found that low concentrations of DOP are relatively safe in vitro and in vivo, respectively. Importantly, we found that DOP treatment significantly inhibited DEX-induced osteoporosis in two in vivo models, zebrafish and mice, while boosting osteogenic differentiation of hBMSCs exposed to DEX. Futhermore, our data reveal that DOP elevates nuclear Nrf2 levels under DEX treatment, by suppressing of Nrf2 ubiquitination. Leveraging Keap1b knockout zebrafish and RNAi approach, we demonstrated that DOP disrupts the association of Nrf2/Keap1, resulting in the inhibition of Nrf2 ubiquitination. Taken together, these results illuminate that DOP stimulates osteogenesis in the presence of DEX by destabilizing the Nrf2/Keap1 interaction. These findings suggest that DOP may serve as a novel drug against osteoporosis caused by glucocorticoids.

Comprehensive evaluation of the prebiotic properties of Dendrobium officinale polysaccharides, β-glucan, and inulin during in vitro fermentation via multi-omics analysis

Dietary fiber is crucial for human health mainly due to its impact on gut microbiota structure and metabolites. This study aimed to investigate the impact of Dendrobium officinale polysaccharides (DOP) and two common fibers (β-glucan and inulin) on the gut microbiome structure and metabolic profile in vitro. Fecal samples were obtained from 30 healthy volunteers, which were then individually subjected to fermentation with each type of fiber. The results revealed that all fibers were efficiently degraded by gut microbiota, with DOP exhibiting a slower fermentation rate compared to β-glucan and inulin. The fermentation of all fibers led to a significant increase in the production of short-chain fatty acids (SCFAs) and a reduction in branched-chain fatty acids (BCFAs), sulfides, phenols, and indole. Moreover, the abundance of unclassified Enterobacteriaceae, which was positively correlated with sulfide, phenols, and indole levels, was significantly reduced by all fibers. Additionally, DOP specifically promoted the growth of Parabacteroides, while β-glucan and inulin promoted the growth of Bifidobacterium and Faecalibacterium. Taken together, these findings enhance our understanding of the role of DOP, β-glucan, and inulin in modulating gut microbiota and metabolites, where the fermentation with fecal bacteria from different volunteers could provide valuable insights for personalized therapeutic approaches.

Moxibustion improved the effect of fecal microbiota transplantation donor to dextran sulfate sodium-induced colitis in mice

Fecal microbiota transplantation (FMT) is beneficial for several gastrointestinal diseases because it alters the intestinal microbiota of recipients. The efficacy of FMT is related to the microbial structure and composition of the donor. Mild moxibustion is a non-invasive and safe traditional Chinese therapy that can regulate the gut microbiota. In this study, we investigated whether moxibustion improved the efficacy of FMT in donors using a dextran sulfate sodium (DSS)-induced colitis mouse model. Normal mice were treated with mild moxibustion at acupoints ST25 and ST36 for 7 days. DSS (2%) was administered for 7 days to induce colitis. FMT was performed on Day 8 and lasted for 7 days. The effect of FMT on mice with DSS was observed on Day 21. Using hematoxylin and eosin staining and immunofluorescence, we analyzed the pathology and cell proliferation after FMT in DSS mice. In addition, using 16 S rDNA sequencing analysis, we investigated the gut microbiota of mice. The results indicated that moxibustion altered the colonic microbial community and increased the relative abundance of specific bacteria without changes in morphology and physiological function in normal mice. FMT using donors with moxibustion reduced body weight loss, inflammation, abnormal microbial community structure, and the relative abundance of some bacteria. These results provide potential strategies for the safe and targeted improvement of FMT donors.

Preclinical pharmacokinetics-related pharmacological effects of orally administered polysaccharides from traditional Chinese medicines: A review

Polysaccharides (TCMPs) derived from traditional Chinese medicines (TCMs), such as Ganoderma lucidum, Astragalus membranaceus, Lycium barbarum, and Panax ginseng, are considered to be the main active constituents in TCMs. However, the significant pharmacological effects of orally administered TCMPs do not align well with their poor pharmacokinetics. This article aims to review the literature published mainly from 2010 to 2022, focusing on the relationship between pharmacokinetics and pharmacological effects. It has been found that unabsorbed TCMPs can exert local pharmacological effects in the gut, including anti-inflammation, anti-oxidation, regulation of intestinal flora, modulation of intestinal immunity, and maintenance of intestinal barrier integrity. Unabsorbed TCMPs can also produce systemic pharmacological effects, such as anti-tumor activity and immune system modulation, by regulating intestinal flora and immunity. Conversely, some TCMPs can be absorbed and distributed to various tissues, especially the liver, where they exhibit tissue-protecting effects against inflammation and oxidative stress-induced damage and improve glucose and lipid metabolism. In future studies, it is important to improve quality control and experimental design. Furthermore, research on enhancing the oral bioavailability of TCMPs, exploring the activity of TCMP metabolites, investigating pharmacokinetic interactions between TCMPs and oral drugs, and developing oral drug delivery systems using TCMPs holds great significance.

Parabacteroides distasonis ameliorates insulin resistance via activation of intestinal GPR109a

Gut microbiota plays a key role in insulin resistance (IR). Here we perform a case-control study of Chinese adults (ChiCTR2200065715) and identify that Parabacteroides distasonis is inversely correlated with IR. Treatment with P. distasonis improves IR, strengthens intestinal integrity, and reduces systemic inflammation in mice. We further demonstrate that P. distasonis-derived nicotinic acid (NA) is a vital bioactive molecule that fortifies intestinal barrier function via activating intestinal G-protein-coupled receptor 109a (GPR109a), leading to ameliorating IR. We also conduct a bioactive dietary fiber screening to induce P. distasonis growth. Dendrobium officinale polysaccharide (DOP) shows favorable growth-promoting effects on P. distasonis and protects against IR in mice simultaneously. Finally, the reduced P. distasonis and NA levels were also validated in another human type 2 diabetes mellitus cohort. These findings reveal the unique mechanisms of P. distasonis on IR and provide viable strategies for the treatment and prevention of IR by bioactive dietary fiber.

Structure, Health Benefits, Mechanisms, and Gut Microbiota of Dendrobium officinale Polysaccharides: A Review

Dendrobium officinale polysaccharides (DOPs) are important active polysaccharides found in Dendrobium officinale, which is commonly used as a conventional food or herbal medicine and is well known in China. DOPs can influence the composition of the gut microbiota and the degradation capacity of these symbiotic bacteria, which in turn may determine the efficacy of dietary interventions. However, the necessary analysis of the relationship between DOPs and the gut microbiota is lacking. In this review, we summarize the extraction, structure, health benefits, and related mechanisms of DOPs, construct the DOPs-host axis, and propose that DOPs are potential prebiotics, mainly composed of 1,4-β-D-mannose, 1,4-β-D-glucose, and O-acetate groups, which induce an increase in the abundance of gut microbiota such as Lactobacillus, Bifidobacterium, Akkermansia, Bacteroides, and Prevotella. In addition, we found that when exposed to DOPs with different structural properties, the gut microbiota may exhibit different diversity and composition and provide health benefits, such as metabolism regulations, inflammation modulation, immunity moderation, and cancer intervention. This may contribute to facilitating the development of functional foods and health products to improve human health.

Chemical Constituents, Bioactivities, and Pharmacological Mechanisms of Dendrobium officinale: A Review of the Past Decade

Dendrobium officinale, a plant in the Orchidaceae family, has been used in traditional Chinese medicine for thousands of years. Sweet and slightly cold in nature, it can invigorate the stomach, promote fluid production, nourish Yin, and dissipate heat. Over the past decade, more than 60 compounds have been derived from D. officinale, including flavonoids, bibenzyl, and phenanthrene. Various studies have explored the underlying pharmacological mechanisms of these compounds, which have shown antitumor, hypoglycemic, hypertensive, gastrointestinal-regulatory, visceral organ protection, antiaging, and neurorestorative effects. This paper presents a systematic review of the structural classification, biological activity, and pharmacological mechanisms of different chemical components obtained from D. officinale over the past decade. This review aims to provide a reference for future study and establish a foundation for clinical applications. Furthermore, this review identifies potential shortcomings in current research as well as potential directions and methodologies in future plant research.

A pectic polysaccharide isolated from Achyranthes bidentata is metabolized by human gut Bacteroides spp

Achyranthes bidentata (A. bidentata) is a famous traditional Chinese medicine (TGM) for treatment osteoporosis. Polysaccharides, a major factor for shaping the gut microbiota, are the primary ingredients of A. bidentata. However, bioactivity of A. bidentata polysaccharide on human gut microbiota (HGM) remains unknown. Here, a homogeneous pectic polysaccharide A23-1 with average molecular weight of 93.085 kDa was extracted and purified from A. bidentata. And A23-1 was compsed of rhamnose, glucuronic acid, galacturonic acid, glucose, galactose and arabinose in a molar ratio of 7.26: 0.76: 5.12: 2.54: 23.51: 60.81. GC-MS, partial acid hydrolysis and NMR results indicated the backbone of A23-1 was composed of 1, 2, 4-Rhap and 1, 4-GlapA, while the branches were composed of galactose, arabinose, glucose and glucuronic acid. Further, A23-1 was found to be degraded into monosaccharides and fragments. Taking Bacteroides thetaiotaomicron (BT) as a model, we suggested three polysaccharide utilization loci (PULs) might be involved in the A23-1 degradation. Degraded products generated by BO might not support the growth of probiotics. Besides, acetate and propionate as the main end products were generated by Bacteroides spp. and probiotics utilizing A23-1. These findings suggested A23-1 was possible one of food sources of human gut Bacteroides spp.

Degradation of xylan by human gut Bacteroides xylanisolvens XB1A

Although many polysaccharides utilization loci (PULs) have been investigated by genomics and transcriptomics, the detailed functional characterization lags severely behind. We hypothesize that PULs on the genome of Bacteroides xylanisolvens XB1A (BX) dictate the degradation of complex xylan. To address, xylan S32 isolated from Dendrobium officinale was employed as a sample polysaccharide. We firstly showed that xylan S32 promoted the growth of BX which might degrade xylan S32 into monosaccharides and oligosaccharides. We further showed that this degradation was performed mainly via two discrete PULs in the genome of BX. Briefly, a new surface glycan binding protein (SGBP) BX_29290^SGBP was identified, and shown to be essential for the growth of BX on xylan S32. Two cell surface endo-xylanases Xyn10A and Xyn10B cooperated to deconstruct the xylan S32. Intriguingly, genes encoding Xyn10A and Xyn10B were mainly distributed in the genome of Bacteroides spp. In addition, BX metabolized xylan S32 to produce short chain fatty acids (SCFAs) and folate. Taken together, these findings provide new evidence to understand the food source of BX and the BX-directed intervention strategy by xylan.

Traditional uses, chemical compositions and pharmacological activities of Dendrobium: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Dendrobium is a kind of medicine food homology plant. Dendrobium has long been used to strengthen "Yin" and tonify five viscera.

AIM OF THIS REVIEW

This paper presents a systematic review of the folk usage, chemical composition and pharmacological activity of Dendrobium, aiming to provide a reference for subsequent in-depth understanding and better exploitation of health food, medicine, and natural products.

MATERIALS AND METHODS

Available information about the genus Dendrobium was collected via Web of Science, PubMed, Science Direct, Scopus, APA-Psy Articles, Google Scholar, Connected Papers, Springer Search, and KNCI. The keywords for this article are Dendrobium, traditional use, chemical diversity and pharmacological activity. Use the "Dictionary of Chinese Ethnic Medicine" to provide 23 kinds of Dendrobium with medicinal value, the Latin name of Dendrobium is verified by the Flora of China (www.iplant.cn), and its species distribution and related information are collected.

RESULTS

There are 78 species of Dendrobium in China, 14 of which are endemic to China. At present, 450 compounds including sesquiterpenoids, lignans compounds, phenolic compounds, phenanthrene compounds, bibenzyls, polysaccharides and flavonoids have been isolated and identified from at least 50 species of Dendrobium. Among them, bibenzyls and polysaccharides are the main active components, phenolics and lignans are widely distributed, sesquiterpenes are the most common chemical constituents in genus Dendrobium plants. The most popular research objects are Dendrobium officinale and Dendrobium huoshanense.

CONCLUSIONS

Based on traditional folk uses, chemical composition and pharmacological studies, Dendrobium is considered a promising medicinal and edible plant with multiple pharmacological activities. In addition, a large number of clinical applications and further studies on single chemical components based on the diversity of chemical structures should be conducted, which will lay the foundation for the scientific utilization of genus Dendrobium.

Dendrobium as a new natural source of bioactive for the prevention and treatment of digestive tract diseases: A comprehensive review with future perspectives

BACKGROUND

The incidence of diseases related to the digestive tract is on the rise, with many types of complex etiologies. Dendrobium nobile Lindl. is a famous Traditional Chinese Medicine (TCM) rich in many bioactives proven to be beneficial in several health diseases related to inflammation and oxidative stress.

PURPOSE

At present, despite the availability of various therapeutic clinical drugs used for the treatment of digestive tract diseases, resistance emergence and existence of several side effects warrant for the developing of novel drugs for improved effects on digestive tract diseases.

METHODS

"Orchidaceae", "Dendrobium", "inflammation", "digestive tract", and "polysaccharide" were used as search terms to screen the literature. The therapeutic use of Dendrobium related to digestive tract diseases relative to known polysaccharides and other bioactive compounds were derived from online databases, including Web of Science, PubMed, Elsevier, Science Direct, and China National Knowledge Infrastructure, as well as relevant information on the known pharmacological actions of the listed phytochemicals.

RESULTS

To better capitalize upon Dendrobium for preventing and treating diseases related to digestive tract, this review summarizes bioactives in Dendrobium reported of potential in digestive tract diseases management and their underlying action mechanisms. Studies revealed that Dendrobium encompasses diverse classes including polysaccharides, phenolics, alkaloids, bibenzyls, coumarins, phenanthrene and steroids, with polysaccharide as the major class. Dendrobium exerts various health effects on a variety of disease related to the digestive tract. Action mechanisms involve antioxidant, anti-inflammatory, anti-apoptotic, antioxidant, anticancer, alongside the regulation of some key signaling pathways.

CONCLUSION

Overall, Dendrobium appears as a promising TCM source of bioactives that has the potential to be further developed into nutraceuticals for digestive tract diseases compared to current drug treatments. This review highlights for Dendrobium potential effects with future perspectives for needed future research to maximize the use of bioactive compounds from Dendrobium for digestive tract disease treatment. A compile of Dendrobium bioactives is also presented alongside methods for their extraction and enrichment for potential incorporation in nutraceuticals.

The linkage of gut microbiota and the property theory of traditional Chinese medicine (TCM): Cold-natured and sweet-flavored TCMs as an example

ETHNOPHARMACOLOGICAL RELEVANCE

The property theory of traditional Chinese medicine (TCM) is a unique medical theory based on an extensive clinical practice for thousands of years, which guides TCM doctors choosing proper medicines to treat specific diseases. The nature and flavor of TCM are a high generalization of drug's characteristics according to the property theory. Despite intensive investigations, the modern interpretation of TCM property theory still confronts several challenges, which greatly hampers the elucidation of TCM's mechanisms as well as its application. Compelling evidence has proved that gut microbiota may be a potential indicator for TCM's efficacy and mechanism. Nevertheless, at present, the relationship between the gut microbiota and the nature and flavor of TCM has not been fully elucidated.

AIM OF THE STUDY

To fill the gap in this field, we developed a comprehensive study to investigate the relationship between gut microbial community and TCM's property.

MATERIALS AND METHODS

We searched "PubMed" and "China National Knowledge Infrastructure (CNKI)" with the key word "gut microbiota", and screened the published articles related to TCM. In this review, we mainly applied cold-natured and sweet-flavored TCMs as an example to explore the modulation of cold-natured and sweet-flavored TCMs on gut microbiota, and identify the potential relationship between the alterations of gut microbiota and TCM's efficacy.

RESULTS

We found cold-natured and sweet-flavored TCMs possess several pharmacological activities and generally enrich beneficial bacteria like Akkermansia, Bacteroides, Lactobacillus and Bifidobacterium, which is in good accordance with their pharmacological effects. Simultaneously, these TCMs reduce the relative abundance of some harmful bacteria belonging to Firmicutes (Streptpcoccus, Enterococcus, Turicibacter, Anaerostipes and Oscillibacter) and Proteobacteria (Helicobacter, Enterobacter, Sutterella, Klebsiella, Desulfovibrio, Escherichia coli and Campylobacter jejuni). These results indicate that there are some intrinsic correlations between gut microbiota and the property of TCM, and gut microbiota may serve as a potential indicator to reflect the property of TCM.

CONCLUSIONS

This pilot but comprehensive review provides an interesting proposal that the ancient theory of TCM property may be interpreted by the modern biological findings in gut microbiome.

A structure defined pectin SA02B from Semiaquilegia adoxoides is metabolized by human gut microbes

Polysaccharide is one of the major factors for shaping the gut microbiota. However, bioactivity of polysaccharide isolated from Semiaquilegia adoxoides on human gut microbiota remains unclear. Thus, we hypothesize gut microbes may act on it. Herein, pectin SA02B from the roots of Semiaquilegia adoxoides with molecular weight 69.26 kDa was elucidated. The backbone of SA02B was composed of alternate 1, 2-linked α-Rhap and 1, 4-linked α-GalpA, with branches of terminal (T) -, 1, 4-, 1, 3- and 1, 3, 6-linked β-Galp, T-, 1, 5- and 1, 3, 5-linked α-Araf and T-, 1, 4-linked-β-Xylp substituted at C-4 of 1, 2, 4-linked α-Rhap. Bioactivity screening showed SA02B promoted the growth of Bacteroides spp. which deconstructed it into monosaccharide. Simultaneously, we observed competition might exist between Bacteroides spp. and probiotics. Besides, we found that both Bacteroides spp. and probiotics could generate SCFAs grown on SA02B. Our findings highlight SA02B may deserve as a prebiotic to be explored to benefit the health gut microbiota.

Structure, anti-fatigue activity and regulation on gut microflora in vivo of ethanol-fractional polysaccharides from Dendrobium officinale

This study was to investigate the antifatigue, prebiotic effects and their relationships to the structure properties of three ethanol precipitated polysaccharides from Dendrobium officinale (EPDO), as EPDO-40, EPDO-60 and EPDO-80. EPDOs with anti-fatigue activity were screened out by forced swimming test, and blood lactic acid (BLA), blood urea nitrogen (BUN), superoxide dismutase (SOD), liver glycogen, muscle glycogen, and intestinal microflora were investigated. Results showed that purified EPDO-60, 277.3 kDa, with a backbone consisted of 4-Manp and 4-Glcp. EPDO-60 had the best anti-fatigue activity, because it could significantly prolong the forced swimming time, as well as down-regulating the levels of BLA and BUN, increasing SOD. Proportions of Bacteroidetes and Firmicutes and abundance of Lactobacillus and Bifidobacterium in gut microflora increased after treated with EPDO-60. Accordingly, EPDO-60 could affect the community structure of gut microflora, leading to promote the balance of oxidation and antioxidation, and accelerated the fatigue metabolism in vivo.

Effect of Dendrobium officinale polysaccharides on central nervous system disease: Based on gut microbiota

Dendrobium officinale has anti-inflammatory effects and is one of the well-known functional foods. Dendrobium officinale polysaccharide (DOP) can reduce intestinal barrier disruption and excessive inflammatory response by regulating intestinal bacterial homeostasis as well as short-chain fatty acid levels. It can also inhibit the activation of astrocytes and microglia, further realizing the protective effect on neuronal apoptosis and apoptosis, thus exerting a significant alleviating effect on neurological diseases. There is now evidence that bidirectional communication between the central nervous system and the gastrointestinal tract may influence human neurology, cognition and behavior via the gut-brain axis. In this review, we review the structural characterization, bioactivity and possible bioactive mechanisms of DOP, so as to elucidate the advantages of DOP's action on CNS diseases, with the aim of providing new perspectives for its drug and functional food development as well as clinical applications.

Neuroprotection of Food Bioactives in Neurodegenerative Diseases: Role of the Gut Microbiota and Innate Immune Receptors

Gut-brain connections may be mediated by an assortment of microbial molecules, which can subsequently traverse intestinal and blood-brain barriers and impact neurological function. Pattern recognition receptors (PRRs) are important innate immune proteins in the gut. Gut microbiota act in concert with the PRRs is a novel target for regulating host-microbe signaling and immune homeostasis, which may involve the pathogenesis of neurodegenerative diseases. Natural food bioactives bestow a protective advantage on neurodegenerative diseases through immunomodulatory effects of the modified gut microbiota or alterations in the landscape of microbiota-produced metabolites via PRRs modulation. In this review, we discuss the effect of natural food bioactives on the gut microbiota and the role of PRRs in the gut-brain crosstalk. We focused on the neuroprotective mechanisms of natural bioactive compounds behind the action of the gut microbiota and PRRs. Research advances in natural food bioactives as antineurodegeneration agents were also presented.

Modern interpretation of the traditional application of Shihu - A comprehensive review on phytochemistry and pharmacology progress of Dendrobium officinale

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Chinese medicine (TCM) "Shihu" has a long history of medicinal use in China from some species of Dendrobium. D. officinale is a major source of "Shihu" and is widely cultivated in south of China and listed separately as "Tiepi Shihu" by the Chinese Pharmacopoeia in now time. Traditionally, D. officinale has been widely used in daily health care and the treatment of diabetes and gastrointestinal diseases.

AIM OF THIS REVIEW

In order to better develop and utilize D. officinale, we conducted this systematic review of previous studies, showed clear structure of all isolates from D. officinale together with pharmacological progress, hoping to provide references for further research and utilization. In addition, specific display of the chemical components and the research progress of related activities can help to better understand the traditional records and modern pharmaceutical applications of the plant medicine.

MATERIALS AND METHODS

Information on phytochemistry and pharmacological studies of D. officinale was collected from various scientific databases including Web of Science, SciFinder, ACS, Springer, Scopus, PubMed, ScienceDirect, Google Scholar and CNKI.

RESULTS

More than 180 compounds isolated from D. officinale, including bibenzyls, phenols, phenylpropanoids, lignans, flavonoids and polysaccharides are listed in this review. Furthermore, modern pharmacological researches such as hypoglycemia, immune regulation, antioxidant, cardiovascular regulation and gastrointestinal protection are summarized.

CONCLUSION

Based on the summary of the research work of D. officinale, we systematically show the chemical composition of the plant, and concluded the relationship of those composition with plant habitat together with the relationship between the structure of chemical components and pharmacological activity. Moreover, we suggest that some of small molecule compounds could also be quality control of D. officinale besides polysaccharides.

Simultaneous determination of nine phenolic compounds in imitation wild Dendrobium officinale samples using ultrahigh-performance liquid chromatography-tandem mass spectrometry

Dendrobium officinale Kimura et Migo (D. officinale), one of the nine everlasting types of grass, has gained increasing attention owing to its important roles in alternative medicines and drug discovery. Due to its natural resources being in danger of being extinct, imitation wild planting is becoming increasingly common. To assess the product's quality completely, an efficient ultrahigh performance liquid chromatography-triple quadrupole tandem mass spectrometry (UHPLC-QQQ-MS/MS) method was established to simultaneously quantify nine phenolic compounds in D. officinale samples. The extraction parameters, including solvent, solvent concentration, solid-liquid ratio, and extraction time, were systematically optimized with the single-factor test. The results demonstrated that extraction with a 1:200 solid-to-liquid ratio of 80% methanol for 1.5 h was the most efficient condition for the extraction of flavonoids. Satisfactory retention times and resolution of the nine analytes were acquired on the Thermo Scientific Hypersil GOLD column with multiple reaction monitoring in negative ion scanning mode. The method was validated to demonstrate its selectivity, linearity, precision, accuracy, and robustness. Thus, the verified UHPLC-QQQ-MS/MS method was successfully applied to the quantification of phenolic components present in D. officinale samples. The results indicated that the quantity and composition of phenolic components in D. officinale from various provenances were significantly different. This work provides a theoretical foundation for the cultivation and assessment of wild D. officinale quality.

Combined Physical Exercise and Diet: Regulation of Gut Microbiota to Prevent and Treat of Metabolic Disease: A Review

BACKGROUND

Unhealthy diet and sedentary lifestyle have contributed to the rising incidence of metabolic diseases, which is also accompanied by the shifts of gut microbiota architecture. The gut microbiota is a complicated and volatile ecosystem and can be regulated by diet and physical exercise. Extensive research suggests that diet alongside physical exercise interventions exert beneficial effects on metabolic diseases by regulating gut microbiota, involving in the changes of the energy metabolism, immune regulation, and the microbial-derived metabolites.

OBJECTIVE

In this review, we present the latest evidence in the modulating role of diet and physical exercise in the gut microbiota and its relevance to metabolic diseases. We also summarize the research from animal and human studies on improving metabolic diseases through diet-plus-exercise interventions, and new targeted therapies that might provide a better understanding of the potential mechanisms.

METHODS

A systematic and comprehensive literature search was performed in PubMed/Medline and Web of Science in October 2022. The key terms used in the searches included "combined physical exercise and diet", "physical exercise, diet and gut microbiota", "physical exercise, diet and metabolic diseases" and "physical exercise, diet, gut microbiota and metabolic diseases".

CONCLUSIONS

Combined physical exercise and diet offer a more efficient approach for preventing metabolic diseases via the modification of gut microbiota, abating the burden related to longevity.

Effect of Resistant Dextrin on Intestinal Gas Homeostasis and Microbiota

Previous studies have shown that a resistant dextrin soluble fibre has prebiotic properties with related health benefits on blood glucose management and satiety. Our aim was to demonstrate the effects of continuous administration of resistant dextrin on intestinal gas production, digestive sensations, and gut microbiota metabolism and composition. Healthy subjects (n = 20) were given resistant dextrin (14 g/d NUTRIOSE^®, Roquette Frères, Lestrem, France) for four weeks. Outcomes were measured before, at the beginning, end, and two weeks after administration: anal evacuations of gas during daytime; digestive perception, girth, and gas production in response to a standard meal; sensory and digestive responses to a comfort meal; volume of colonic biomass by magnetic resonance; taxonomy and metabolic functions of fecal microbiota by shotgun sequencing; metabolomics in urine. Dextrin administration produced an initial increase in intestinal gas production and gas-related sensations, followed by a subsequent decrease, which magnified after discontinuation. Dextrin enlarged the volume of colonic biomass, inducing changes in microbial metabolism and composition with an increase in short chain fatty acids-producing species and modulation of bile acids and biotin metabolism. These data indicate that consumption of a soluble fibre induces an adaptative response of gut microbiota towards fermentative pathways with lower gas production.

Ephedra sinica polysaccharide alleviates airway inflammations of mouse asthma-like induced by PM2.5 and ovalbumin via the regulation of gut microbiota and short chain fatty acid

Objectives

Epidemiological investigations show that long-term exposure to PM2.5 is directly related to asthma-like and other respiratory diseases. This study aims to further explore the pharmacological effect of Ephedra sinica polysaccharide (ESP) on lung injury caused by atmospheric PM2.5.

Methods

To achieve the aim, we explored the therapeutic effect of ESP on an aggravated asthma-like mouse induced by PM2.5 combined with ovalbumin (OVA), and explored mechanisms underlying the connection between gut microbiota and lung function.

Key findings

Preliminary results showed that ESP alleviated the symptoms of aggravated allergic asthma-like in mice; reduced the number of eosinophils in BALF; reduced the levels of serum Ig-E, IL-6, TNF-α, and IL-1β. Further qRT-PCR detected that ESP inhibited the NF-κB pathway. The final analysis detected by 16S rRNA and short chain fatty acid (SCFA) confirmed that ESP increased relative proportions of Bacteroides, Lactobacillus, Prevotella, Butyricicoccus and Paraprevotella, but decreased that of Enterococcus and Ruminococcus; increased acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid, and isohexanic acid in the meanwhile.

Conclusions

The study showed that ESP has a potential for future therapeutical applications in the prevention and treatment of asthma-like disease induced by PM2.5 and OVA via regulation of gut microbiota and SCFA.

Bioactivities and Mechanism of Actions of Dendrobium officinale: A Comprehensive Review

Dendrobium officinale has a long history of being consumed as a functional food and medicinal herb for preventing and managing diseases. The phytochemical studies revealed that Dendrobium officinale contained abundant bioactive compounds, such as bibenzyls, polysaccharides, flavonoids, and alkaloids. The experimental studies showed that Dendrobium officinale and its bioactive compounds exerted multiple biological properties like antioxidant, anti-inflammatory, and immune-regulatory activities and showed various health benefits like anticancer, antidiabetes, cardiovascular protective, gastrointestinal modulatory, hepatoprotective, lung protective, and neuroprotective effects. In this review, we summarize the phytochemical studies, bioactivities, and the mechanism of actions of Dendrobium officinale, and the safety and current challenges are also discussed, which might provide new perspectives for its development of drug and functional food as well as clinical applications.

Research Progress on the Mechanisms of Polysaccharides against Gastric Cancer

Gastric cancer is a common type of cancer that poses a serious threat to human health. Polysaccharides are important functional phytochemicals, and research shows that polysaccharides have good anti-gastric cancer effects. We collated all relevant literature published from 2000 to 2020 and found that more than 60 natural polysaccharides demonstrate anti-gastric cancer activity. At the present, the sources of these polysaccharides include fungi, algae, tea, Astragalus membranaceus, Caulis Dendrobii, and other foods and Chinese herbal medicines. By regulating various signaling pathways, including the PI3K/AKT, MAPK, Fas/FasL, Wnt/β-catenin, IGF-IR, and TGF-β signaling pathways, polysaccharides induce gastric cancer cell apoptosis, cause cell cycle arrest, and inhibit migration and invasion. In addition, polysaccharides can enhance the immune system and killing activity of immune cells in gastric cancer patients and rats. This comprehensive review covers the extraction, purification, structural characterization, and mechanism of plant and fungal polysaccharides against gastric cancer. We hope this review is helpful for researchers to design, research, and develop plant and fungal polysaccharides.

Wheat supplement with buckwheat affect gut microbiome composition and circulate short-chain fatty acids

Buckwheat has beneficial effects on human intestinal health, which is often compounded with wheat to make food. Therefore, the effect of cereals mixture via in vitro fermentation on gut microbes and short-chain fatty acids (SCFAs) were investigated in this study. The mixture of wheat and tartary buckwheat (WT) produced more lactate and acetate, and the mixture of wheat and sweet buckwheat (WE) produced more propionate and butyrate. Compared with wheat (WA), the relative abundance of some beneficial bacteria significantly increased, such as Sutterella in WT and Faecalibacterium in WE. Cereals mixture also affected the expression of functional genes, involved in metabolic pathways and carbohydrate-active enzymes (CAZymes) that modulated SCFAs generation. This study provides new insights into the effects of sweet and tartary buckwheat on intestinal function, which is beneficial to applying both types of buckwheat in practical.

Effects of Sheep Bone Collagen Peptide on Liver Lipid Deposition in Ovariectomized Rats

Liver can be directly involved in the synthesis and decomposition of fatty acids. Liver lipid deposition is one of the most common chronic liver diseases. Estrogen deficiency can cause lipid deposition and energy metabolism disorders in the liver. Sheep bone collagen peptide (SBCP) has been shown to have estrogen-like effects in previous studies. And SBCP has high bioavailability, safety and non-toxic side effects. This study aimed to investigate the effect of SBCP on liver lipid deposition (LLD) caused by estrogen deficiency. Female Wistar rats were treated as follows (n=10): sham group: underwent peri-ovary fat removal operations, ovariectomized rats (model group), ovariectomized rats receiving SBCP treatments: SBCP high dose group (SBCP-H), SBCP medium dose group (SBCP-M) and SBCP low dose group (SBCP-L). After 8 wk, the model group demonstrated severe LLD and liver pathological changes, with increased malondialdehyde (MDA) and free fatty acid (FFA) levels (p<0.05). Additionally, the total superoxide dismutase (T-SOD) activity (p<0.05), serum albumin-to-globulin (A/G) ratio (p<0.05), amount of butyric acid-producing bacteria and short-chain fatty acids (SCFAs) content decreased. SBCP intervention could inhibit the occurrence of LLD and alleviate the liver histopathological damage induced by estrogen deficiency by relieving oxidative stress, preventing the loss of butyric acid-producing bacteria, and decreasing the abundance of Lactobacillus reuteri in the gut. The results suggested that SBCP could improve the LLD indecued by estrogen deficiency.

Dendrobium officinale polysaccharide inhibits vascular calcification via anti-inflammatory and anti-apoptotic effects in chronic kidney disease

Vascular calcification is very common in patients with chronic kidney disease (CKD), but so far, there is no effective treatment. Dendrobium officinale polysaccharide (DOP), a natural component of Chinese herbal medicine, has been shown to exert anti-inflammatory and anti-apoptotic activity. Inflammation and apoptosis play an essential role in the progression of vascular calcification. However, the exact role and molecular mechanisms of DOP in vascular calcification remain unclear. In this study, we investigated the effects of DOP on vascular calcification using vascular smooth muscle cells (VSMCs), arterial rings, and CKD rats. Alizarin red staining and gene expression analysis revealed that DOP inhibited calcification and osteogenic differentiation of rat VSMCs in a dose-dependent manner. Similarly, ex vivo studies revealed that DOP inhibited the calcification of rat arterial rings. Furthermore, the administration of DOP alleviated vascular calcification in CKD rats. Moreover, DOP treatment suppressed VSMC inflammation and apoptosis. Finally, DOP treatment upregulated mRNA and protein levels of heme oxygenase-1 (HMOX-1); both pharmacological inhibition of HMOX-1 by the HMOX-1 inhibitor zinc protoporphyrin-9ZnPP9 and knockdown of HMOX-1 by siRNA markedly abrogated the suppression of inflammation and osteogenic differentiation of VSMCs by DOP. Collectively, these results suggest that DOP alleviates vascular calcification in CKD by suppressing apoptosis and inflammation via HMOX-1 activation. These results may provide a promising treatment for vascular calcification in CKD.

Chemical constituents from the stems of Dendrobium gratiosissimum and their biological activities

Eight C₆-C₃-based bibenzyl derivatives (dengraphenols A-G, K), three mono-bibenzyls (dengraphenols I, L-M), one bis-bibenzyl (dengraphenol H), one oxyneolignane (dengraphenol J), one phenanthrene (dengraphenol N), and one picrotoxane-type sesquiterpene (dengrasusane A) were isolated from the stems of Dendrobium gratiosissimum. The resolution of dengraphenols A-J by chiral HPLC afforded ten pairs of enantiomers [(±)-dengraphenols A-J]. Their structures with absolute configurations were elucidated on the basis of comprehensive spectroscopic analyses, computational calculation methods and single-crystal X-ray diffraction, among which twenty-four [(±)-dengraphenols A-E, (+)-dengraphenol F, (±)-dengraphenols G-J, dengraphenols K-N, dengrasusane A] were undescribed. Ten compounds [(±)-dengraphenol B, (±)-dengraphenols D-E, (±)-dengraphenol H, (-)-dengraphenol I and dengraphenol N)] showed potent cytotoxicity against eight human cancer cell lines (A431, A2780, H460, HCT8, BGC823, SW1990, Daoy, and HGC27) with IC₅₀ values of 3.77-9.75 μM. At a concentration of 10 μM, (-)-dengraphenol C, (±)-dengraphenol F, and (±)-dengraphenol K exhibited remarkable hepatoprotective activity against APAP-induced toxicity with a cell survival rate of 65.8%, 70.6% and 73.5%, respectively; dengraphenol N displayed significant anti-inflammatory effects; and dengraphenol K showed strong inhibitory activity against α-glucosidase with IC₅₀ values of 5.71 μM. These results would provide potential compounds for drug discovery.

Dendrobium officinale Endophytes May Colonize the Intestinal Tract and Regulate Gut Microbiota in Mice

Dendrobium officinale is a traditional Chinese medicine for treating gastrointestinal diseases by nourishing "Yin" and thickening the stomach lining. To study whether D. officinale endophytes can colonize the intestinal tract and regulate gut microbiota in mice, we used autoclave steam sterilizing and 60Co-γ radiation to eliminate D. officinale endophytes from its juice. Then, high-throughput ITS1-ITS2 rDNA and 16S rRNA gene amplicons were sequenced to analyze the microbial community of D. officinale endophytes and fecal samples of mice after administration of fresh D. officinale juice. Sterilization of D. officinale juice by autoclaving for 40 min (ASDO40) could more effectively eliminate the D. officinale endophytes and decrease their interference on the gut microbiota. D. officinale juice could increase beneficial gut microbiota and metabolites including short-chain fatty acids. D. officinale endophytes Pseudomonas mosselii, Trichocladium asperum, Titata maxilliformis, Clonostachys epichloe, and Rhodotorula babjevae could colonize the intestinal tract of mice and modulate gut microbiota after oral administration of the juice for 28 days. Thus, the regulatory effect of D. officinale juice on gut microbiota was observed, which provides a basis for inferring that D. officinale endophytes might colonize the intestinal tract and participate in regulating gut microbiota to treat diseases. Thus, this study further provides a new approach for the treatment of diseases by colonizing plant endophytes in the intestinal tract and regulating gut microbiota.

Comparative study of different liquid diets for dairy calves and the impact on performance and the bacterial community during diarrhea

The liquid diet composition can affect dairy calves' performance and diarrhea incidence. The effect of three liquid diets on performance, incidence of diarrhea, and microbial community during diarrhea occurrence in dairy calves were evaluated. At birth, 35 dairy calves (20 male and 15 female) were randomly assigned to one of three treatments-refrigerated whole milk (WM), acidified whole milk (AWM), and milk replacer (MR). Intake, fecal score, and rectal temperature were evaluated daily, and performance and blood parameters were evaluated weekly during the preweaning period. Fecal samples from diarrheic calves were collected, and one initial and one final sample for each episode were selected. The bacterial community was assessed by sequencing the V3-V4 region of the 16S rRNA gene on the Illumina MiSeq platform and analyzed using the DADA2 pipeline. Calves fed WM had higher body weight at weaning, average daily gain, body measurements, and concentration of blood metabolites. The AWM-fed calves had a lower rectal temperature and fever days. Moreover, the MR-fed calves had lower beta-hydroxybutyrate concentration and a higher incidence of diarrhea. The fecal bacterial community of diarrheic calves showed dissimilarity among the AWM and the other treatments. At the compositional level, we observed a higher abundance of Fusobacterium and Ruminococcus genera (AWM), Prevotella (WM), and Lactobacillus (MR). In the AWM and MR diarrheic calves' feces, we also observed some beneficial bacterial genera. The performance and incidence of diarrhea of dairy calves were influenced by the liquid diet consumed and the bacterial composition of diarrhea.

Codonopsis pilosula oligosaccharides modulate the gut microbiota and change serum metabolomic profiles in high-fat diet-induced obese mice

Obesity has become a major health problem worldwide, linked to gut microbiota imbalance and chronic inflammation. This study aims to evaluate whether Codonopsis pilosula oligosaccharides (CPOs) can alleviate obesity and related metabolic complications in high-fat diet (HFD) induced obese mice. Male C57BL/6J mice were fed with a HFD for 16 weeks and treated daily with CPOs (500 mg kg^-1). CPO supplementation decreased body weight and fat accumulation and improved glucose tolerance in HFD-fed mice. CPOs also reversed the effects of the HFD on inflammatory markers and improved macrophage infiltration. The results of gut microbiota analysis showed that CPOs could also regulate gut microbiota composition, significantly increasing the abundance of the beneficial bacteria Muribaculaceae spp., Alistipes and Clostridium and decreasing the abundance of the harmful bacteria Rikenella, Enterobacteriaceae spp., Collinsella and Megasphaera in HFD mice. Based on serum non-targeted metabolomics analysis, 20 key metabolites responding to CPO treatment were identified, and their biological functions were mainly related to tryptophan and bile acid metabolism. The results demonstrate that CPO supplementation can ameliorate HFD-induced obesity and obesity-related metabolic disorders. It can be used as a novel gut microbiota modulator to prevent HFD-induced gut dysbiosis.

Light and Potassium Improve the Quality of Dendrobium officinale through Optimizing Transcriptomic and Metabolomic Alteration

Background: Dendrobium officinale is a perennial epiphytic herb in Orchidaceae. Cultivated products are the main alternative for clinical application due to the shortage of wild resources. However, the phenotype and quality of D. officinale have changed post-artificial cultivation, and environmental cues such as light, temperature, water, and nutrition supply are the major influencing factors. This study aims to unveil the mechanisms beneath the cultivation-induced variation by analyzing the changes of the metabolome and transcriptome of D. officinale seedlings treated with red- blue LED light and potassium fertilizer. Results: After light- and K-treatment, the D. officinale pseudobulbs turned purple and the anthocyanin content increased significantly. Through wide-target metabolome analysis, compared with pseudobulbs in the control group (P), the proportion of flavonoids in differentially-accumulated metabolites (DAMs) was 22.4% and 33.5% post light- and K-treatment, respectively. The gene modules coupled to flavonoids were obtained through the coexpression analysis of the light- and K-treated D. officinale transcriptome by WGCNA. The KEGG enrichment results of the key modules showed that the DEGs of the D. officinale pseudobulb were enriched in phenylpropane biosynthesis, flavonoid biosynthesis, and jasmonic acid (JA) synthesis post-light- and K-treatment. In addition, anthocyanin accumulation was the main contribution to the purple color of pseudobulbs, and the plant hormone JA induced the accumulation of anthocyanins in D. officinale. Conclusions: These results suggested that light and potassium affected the accumulation of active compounds in D. officinale, and the gene-flavone network analysis emphasizes the key functional genes and regulatory factors for quality improvement in the cultivation of this medicinal plant.

Research progress on extraction, purification, structure and biological activity of Dendrobium officinale polysaccharides

Dendrobium officinale Kimura et Migo (D. officinale) is a traditional medicinal and food homologous plant that has been used for thousands of years in folk medicine and nutritious food. Recent studies have shown that polysaccharide is one of the main biologically active components in D. officinale. D. officinale polysaccharides possess several biological activities, such as anti-oxidant, heptatoprotective, immunomodulatory, gastrointestinal protection, hypoglycemic, and anti-tumor activities. In the past decade, polysaccharides have been isolated from D. officinale by physical and enzymatic methods and have been subjected to structural characterization and activity studies. Progress in extraction, purification, structural characterization, bioactivity, structure-activity relationship, and possible bioactivity mechanism of polysaccharides D. officinale were reviewed. In order to provide reference for the in-depth study of D. officinale polysaccharides and the application in functional food and biomedical research.

Extraction, Structure and Immunoregulatory Activity of Low Molecular Weight Polysaccharide from Dendrobium officinale

The ethanol precipitation method has been widely-used for Dendrobium officinale polysaccharides preparation. However, the alcohol-soluble fractions have always been ignored, which causes significant wastes of resources and energies. In this study, the extraction, physicochemical properties, and immune regulation activity of an edible D. officinale polysaccharide (DOPs) isolated from the supernatant after 75% ethanol precipitation were systematically investigated. The structural characteristics determination results showed that DOPs was mainly composed of glucose and mannose at a molar ratio of 1.00:5.78 with an average molecular weight of 4.56 × 10³ Da, which was made up of α-(1,3)-Glcp as the main skeleton, and the α-(1,4)-Glcp and β-(1,4)-Manp as the branches. Subsequently, the cyclophosphamide (CTX)-induced immunosuppressive mice model was established, and the results demonstrated that DOPs could dose-dependently protect the immune organs against CTX damage, improve the immune cells activities, and promote the immune-related cytokines (IL-2, IFN-γ and TNF-α) secretions. Furthermore, DOPs treatment also effectively enhanced the antioxidant enzymes levels (SOD, GSH-Px) in sera and livers, therefore weakening the oxidative damage of CTX-treated mice. Considering these above data, DOPs presented great potential to be explored as a natural antioxidant and supplement for functional foods.

Fu Brick Tea Manages HFD/STZ-Induced Type 2 Diabetes by Regulating the Gut Microbiota and Activating the IRS1/PI3K/Akt Signaling Pathway

The antidiabetic effects of Fu brick tea aqueous extract (FTE) and its underlying molecular mechanism in type 2 diabetes mellitus (T2DM) mice were investigated. FTE treatment significantly relieved dyslipidemia, insulin resistance (IR), and hepatic oxidative stress caused by T2DM. FTE also ameliorated the T2DM-induced gut dysbiosis by decreasing the Firmicutes/Bacteroidota (F/B) ratio at the phylum level and promoting the proliferation of Bifidobacterium, Parabacteroides, and Roseburia at the genus level. Besides, FTE significantly improved colonic short-chain fatty acid levels of T2DM mice. Furthermore, the antidiabetic effects of FTE were proved to be mediated by the IRS1/PI3K/Akt and AMPK-mediated gluconeogenesis signaling pathways. Metabolomics analysis illustrated that FTE recovered the levels of 28 metabolites associated with T2DM to the levels of normal mice. Taken together, these findings suggest that FTE can alleviate T2DM by reshaping the gut microbiota, activating the IRS1/PI3K/Akt pathway, and regulating intestinal metabolites.

Tracking the gastrointestinal digestive and metabolic behaviour of Dendrobium officinale polysaccharides by fluorescent labelling

Recently, Dendrobium officinale polysaccharide (DOP), a typical acetylated glucomannan, has been widely applied in functional foods owing to its excellent bioactivity. However, the insufficiency of studies on in vivo process severely limits the further utilization of DOP. The aim of this study was to systematically investigate the gastrointestinal digestive behaviour of DOP after oral administration by labelling it with two fluorescein aminopyrene-1,3,6-trisulfonic acids, trisodium salt (APTS) and cyanine 7.5 (Cy7.5). Combining the results of NIR imaging and HPGPC, we found that DOP was poorly absorbed directly in the prototype form; instead, DOP moved with the intestinal contents to the distal part of the intestine, where Bacteroides aggregated for a prolonged time and was metabolized to oligosaccharide-like substances. In contrast, the digestive degradation of DOP in pseudo-sterile mice with a targeted clearance of Bacteroides significantly weakened, which provided the basis and direction for the subsequent search for more specific metabolic pathways of DOP in vivo.