Colon tissue-accumulating mesoporous carbon nanoparticles loaded with Musca domestica cecropin for ulcerative colitis therapy

Timosaponin BⅡ reduces colonic inflammation and alleviates DSS-induced ulcerative colitis by inhibiting NLRP3

ETHNOPHARMACOLOGICAL RELEVANCE

The Timosaponin BⅡ (TBⅡ) is one of the main active components of the traditional Chinese medicine Anemarrhena asphodeloides, and it is a steroidal saponin with various pharmacological activities such as anti-oxidation, anti-inflammatory and anti-apoptosis. However, its role in acute ulcerative colitis remains unexplored thus far.

AIM OF THE STUDY

This study aims to investigate the protective effect of TBⅡ against dextran sulfate sodium (DSS)-induced ulcerative colitis in mice and elucidate its underlying mechanisms.

METHODS

Wild-type (WT) and NLRP3 knockout (NLRP3-/-) mice were applied to evaluate the protective effect of TBⅡ in DSS-induced mice colitis. Pharmacological inhibition of NLRP3 or adenovirus-mediated NLRP3 overexpression in bone marrow-derived macrophages (BMDM) from WT mice and colonic epithelial HCoEpiC cells was used to assess the role of TBⅡ in LPS + ATP-induced cell model. RNA-seq, ELISA, western blots, immunofluorescence staining, and expression analysis by qPCR were performed to examine the alterations of colonic NLRP3 expression in DSS-induced colon tissues and LPS + ATP-induced cells, respectively.

RESULTS

In mice with DSS-induced ulcerative colitis, TBⅡ treatment attenuated clinical symptoms, repaired the intestinal mucosal barrier, reduced inflammatory infiltration, and alleviated colonic inflammation. RNA-seq analysis and protein expression levels demonstrated that TBⅡ could prominently inhibit NLRP3 signaling. TBⅡ-mediated NLRP3 inhibition was associated with alleviating intestinal permeability and inflammatory response via the blockage of communication between epithelial cells and macrophages, probably in an NLRP3 inhibition mechanism. However, pharmacological inhibition of NLRP3 by MCC950 or Ad-NLRP3 mediated NLRP3 overexpression significantly impaired the TBⅡ-mediated anti-inflammatory effect. Mechanistically, TBⅡ-mediated NLRP3 inhibition may be partly associated with the suppression of NF-κB, a master pro-inflammatory factor for transcriptional regulation of NLRP3 expression in the priming step. Moreover, co-treatment TBⅡ with NF-κB inhibitor BAY11-7082 partly impaired TBⅡ-mediated NLRP3 inhibition, and consequently affected the IL-1β mature and secretion. Importantly, TBⅡ-mediated amelioration was not further enhanced in NLPR3-/- mice.

CONCLUSION

TBⅡ exerted a prominent protective effect against DSS-induced colitis via regulation of alleviation of intestinal permeability and inflammatory response via the blockage of crosstalk between epithelial cells and macrophages in an NLRP3-mediated inhibitory mechanism. These beneficial effects could make TBⅡ a promising drug for relieving colitis.

Revitalizing Ancient Mitochondria with Nano-Strategies: Mitochondria-Remedying Nanodrugs Concentrate on Disease Control

Mitochondria, widely known as the energy factories of eukaryotic cells, have a myriad of vital functions across diverse cellular processes. Dysfunctions within mitochondria serve as catalysts for various diseases, prompting widespread cellular demise. Mounting research on remedying damaged mitochondria indicates that mitochondria constitute a valuable target for therapeutic intervention against diseases. But the less clinical practice and lower recovery rate imply the limitation of traditional drugs, which need a further breakthrough. Nanotechnology has approached favorable regiospecific biodistribution and high efficacy by capitalizing on excellent nanomaterials and targeting drug delivery. Mitochondria-remedying nanodrugs have achieved ideal therapeutic effects. This review elucidates the significance of mitochondria in various cells and organs, while also compiling mortality data for related diseases. Correspondingly, nanodrug-mediate therapeutic strategies and applicable mitochondria-remedying nanodrugs in disease are detailed, with a full understanding of the roles of mitochondria dysfunction and the advantages of nanodrugs. In addition, the future challenges and directions are widely discussed. In conclusion, this review provides comprehensive insights into the design and development of mitochondria-remedying nanodrugs, aiming to help scientists who desire to extend their research fields and engage in this interdisciplinary subject.

Cecropin A: investigation of a host defense peptide with multifaceted immunomodulatory activity in a chicken hepatic cell culture

Introduction

Host defense peptides (HDPs) are increasingly referred to as promising candidates for the reduction of the use of conventional antibiotics, thereby combating antibiotic resistance. As HDPs have been described to exert various immunomodulatory effects, cecropin A (CecA) appears to be a potent agent to influence the host inflammatory response.

Methods

In the present study, a chicken primary hepatocyte-non-parenchymal cell co-culture was used to investigate the putative immunomodulatory effects of CecA alone and in inflammatory conditions evoked by polyinosinic-polycytidylic acid (Poly I:C). To examine the viability of the cells, the extracellular lactate dehydrogenase (LDH) activity was determined by colorimetric assay. Inflammatory markers interleukin (IL)-8 and transforming growth factor-ß1 (TGF-ß1) were investigated using the ELISA method, whereas concentrations of IL-6, IL-10, and interferon-γ (IFN-γ) were assayed by Luminex xMAP technology. Extracellular H2O2 and malondialdehyde levels were measured by fluorometric and colorimetric methods, respectively.

Results

Results of the lower concentrations suggested the safe application of CecA; however, it might contribute to hepatic cell membrane damage at its higher concentrations. We also found that the peptide alleviated the inflammatory response, reflected by the decreased production of the pro-inflammatory IL-6, IL-8, and IFN-γ. In addition, CecA diminished the levels of anti-inflammatory IL-10 and TGF-ß1. The oxidative markers measured remained unchanged in most cases of CecA exposure.

Discussion

CecA displayed a multifaceted immunomodulatory but not purely anti-inflammatory activity on the hepatic cells, and might be suggested to maintain the hepatic inflammatory homeostasis in Poly I:C-triggered immune response. To conclude, our study suggests that CecA might be a promising molecule for the development of new immunomodulatory antibiotic-substitutive agents in poultry medicine; however, there is still a lot to clarify regarding its cellular effects.

The effect and mechanism of Huangqin-Baishao herb pair in the treatment of dextran sulfate sodium-induced ulcerative colitis

Background

The haungqing (Scutellariae Radix) and baishao (Paeoniae Radix Alba) herb pair (HBHP) is a common prescribed herbal formula or is added to other traditional Chinese medicine (TCM) prescriptions to treat ulcerative colitis (UC). However, the underlying mechanism is unclear.

Purpose

Elucidate the efficacy and potential mechanism of HBHP against UC.

Methods

First, The UC model of mice induced by dextran sulfate sodium (DSS) was established. The mice were randomly divided into Control group, DSS group, SASP group (390 mg/kg), and HPHP group (1.95 g/kg), with 8 mice per group. Drugs were administrated via oral gavage for 7 days. Then, Disease activity index (DAI), length of the colon, histopathology, and changes in inflammatory cytokines in colonic tissues were analyzed to assess the effect of HBHP on UC. Besides, Network pharmacology was applied to identify the active compounds, core targets of HBHP in the treatment of UC, and the corresponding signaling pathways to explore the underlying mechanisms. Finally, Western blot (WB), immunohistochemistry (IHC) and molecular docking were performed to validate the results.

Results

HBHP significantly reduced DAI score and decreased colon length shortening in DSS-induced UC mice. The administration of HBHP was able to effectively alleviated mucosal ulceration and epithelial destruction. In addition, HBHP treatment obviously - reduced the expressions of TNF-α, IL-6, and IL-1β in colon tissues (p < 0.05 or p < 0.01). 35 bioactive compounds and 290 HBHP targets related to UC were obtained. Among them 3 key active compounds (baicalein, panicolin, and norwogonin) with higher degree values in the drug-compound-target network and 21 hub genes (STAT3, JAK2, SRC, AKT1, PIK3CA, and VEGFA, etc.) were identified. KEGG enrichment analysis suggested that HBHP's mechanisms mainly involve the JAK-STAT pathway. Abnormal activation of JAK/STAT signaling is believed to be involved in the pathogeneses of UC. Notably, WB and IHC showed that HBHP significantly down-regulated the protein expression levels of p-JAK2 (p < 0.05) and p-STAT3 (p < 0.05 or p < 0.01). JAK2 and STAT3 might be core targets for the action of HBHP; this possibility was also supported by molecular docking.

Conclusions

HBHP could alleviate DSS-induced UC, reduce tissue inflammation, and its mechanism might primarily be achieved by inhibiting JAK2/STAT3 signaling pathway. Meanwhile, our work revealed that network pharmacology combined with experimental verification is a cogent means of studying the mechanism of TCM.

Recent advances on emerging nanomaterials for diagnosis and treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic idiopathic inflammatory disorder that affects the entire gastrointestinal tract and is associated with an increased risk of colorectal cancer. Mainstream clinical testing methods are time-consuming, painful for patients, and insufficiently sensitive to detect early symptoms. Currently, there is no definitive cure for IBD, and frequent doses of medications with potentially severe side effects may affect patient response. In recent years, nanomaterials have demonstrated considerable potential for IBD management due to their diverse structures, composition, and physical and chemical properties. In this review, we provide an overview of the advances in nanomaterial-based diagnosis and treatment of IBD in recent five years. Multi-functional bio-nano platforms, including contrast agents, near-infrared (NIR) fluorescent probes, and bioactive substance detection agents have been developed for IBD diagnosis. Based on a series of pathogenic characteristics of IBD, the therapeutic strategies of antioxidant, anti-inflammatory, and intestinal microbiome regulation of IBD based on nanomaterials are systematically introduced. Finally, the future challenges and prospects in this field are presented to facilitate the development of diagnosis and treatment of IBD.

GelNB molecular coating as a biophysical barrier to isolate intestinal irritating metabolites and regulate intestinal microbial homeostasis in the treatment of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic, immune-mediated inflammatory disease characterized by the destruction of the structure and function of the intestinal epithelial barrier. Due to the poor remission effect and severe adverse events associated with current clinical medications, IBD remains an incurable disease. Here, we demonstrated a novel treatment strategy with high safety and effective inflammation remission via tissue-adhesive molecular coating. The molecular coating is composed of o-nitrobenzaldehyde (NB)-modified Gelatin (GelNB), which can strongly bond with –NH₂ on the intestinal surface of tissue to form a thin biophysical barrier. We found that this molecular coating was able to stay on the surface of the intestine for long periods of time, effectively protecting the damaged intestinal epithelium from irritations of external intestinal metabolites and harmful flora. In addition, our results showed that this coating not only provided a beneficial environment for cell migration and proliferation to promote intestinal repair and regeneration, but also achieved a better outcome of IBD by reducing intestinal inflammation. Moreover, the in vivo experiments showed that the GelNB was better than the classic clinical medication—mesalazine. Therefore, our molecular coating showed potential as a promising strategy for the prevention and treatment of IBD.

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GelNB molecular coating can protect the intestinal epithelium from irritations of intestinal metabolites and harmful flora.

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GelNB molecular coating not only promote intestinal repair and regeneration, but also reduce intestinal inflammation.

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GelNB molecular coating shows potential as a promising strategy for the prevention and treatment of IBD.

pH/ROS Dual-Sensitive Natural Polysaccharide Nanoparticles Enhance "One Stone Four Birds" Effect of Rhein on Ulcerative Colitis

Rhein (RH), a natural anthraquinone compound, is considered an effective treatment candidate for ulcerative colitis (UC), whose multiple biological activities contribute to UC, including anti-inflammation, antioxidation, intestinal barrier repair, and microflora regulation. However, the application of RH is severely limited by its low water solubility, low bioavailability, and poor colonic targeting. Although some nanoparticles have been developed for the oral delivery of RH, most of them mainly highlighted only one effect of some drug delivery strategies but the above multiple biological activities. Therefore, a multiple polysaccharide-based nanodelivery system, comprising chitosan (CS) and fucoidan (FU), with pH/reactive oxygen species (ROS) sensitivity and mucosal adhesion, was developed and first used to load RH as a comprehensive treatment for UC. Briefly, RH-F/C-NPs were prepared using the polyelectrolyte self-assembly method; the average size of RH-F/C-NPs was 233.1 ± 5.7 nm, and the encapsulation rate of RH was 93.67 ± 1.60%. And it could maintain gastric stability and release RH in the colon with the designed pH/ROS sensitivity contributed by the polysaccharide-based structures. Cellular uptake experiments showed that both NCM 460 cells and RAW 264.7 cells had a good uptake of RH-F/C-NPs. Importantly, the effects of RH were highlighted in in vivo experiments, the results of which showed that RH-F/C-NPs could significantly reduce DSS-induced inflammation by inhibiting the TLR4/NF-κB-mediated anti-inflammatory pathway, the Nrf2/HO-1-mediated antioxidant pathway, colonic mucosal barrier repair, and intestinal microflora regulation. In addition, pharmacokinetic studies have shown that F/C-NPs contribute to the increase in the plasma concentration and the accumulation of RH in the colon to some extent. In short, this study is the first to develop an oral multiple polysaccharide-based nanosystem with pH/ROS dual sensitivity to study the "one stone four birds" therapeutic effect of RH on UC.

Mesoporous Calcium-Silicate Nanoparticles Loaded with Prussian Blue Promotes Enterococcus Faecalis Ferroptosis-Like Death by Regulating Bacterial Redox Pathway ROS/GSH

Background

Mesoporous calcium-silicate nanoparticles (MCSNs) are advanced biomaterials that have been used to control drug delivery for many years. Ultrasmall Prussian blue nanoparticles (UPBNPs) showed high peroxidase and catalase-like activities. This study evaluated the antibacterial and antibiofilm properties, mechanism and cytotoxicity of UPBNPs-MCSNs composites synthesized by both as precursors.

Methods

UPBNPs-MCSNs were prepared and characterized. The antibacterial effect of UPBNPs-MCSNs was evaluated by the MTT assay and CFU counting method, and their biosafety was tested by CCK8. Then explore the antibacterial mechanism, including TEM observation of bacterial morphology, and detection of bacterial ROS, LPO and GSH levels. The antibiofilm activity of UPBNPs-MCSNs was tested by E. faecalis biofilm model in human roots. The roots were pretreated with materials and cultured with E. faecalis, and the survival of E. faecalis on the root canal wall was observed by SEM and CLSM.

Results

The results showed that UPBNPs-MCSNs had potent antibacterial and antibiofilm activities. They can aggregate on the dentin surface and significantly inhibit E. faecalis adhesion and colonization. Their antibacterial activity is as effective as NaClO and calcium hydroxide (CH), can significantly prolong the time of bacterial colonization than CH, but have lower cytotoxicity to normal cells. We found that UPBNPs-MCSNs trigger a like classic ferroptosis pathway in bacteria. UPBNPs-MCSNs can induce bacteria to produce ROS and LPO, and reduce GSH level. Moreover, we observed that the metal ions chelator and the antioxidant could block their antibacterial activity.

Conclusion

These results reveal that UPBNPS-MCSNs have high antibacterial and antibiofilm, and can mediate the bacterial redox pathway ROS/GSH like the classical pathway of ferroptosis, providing a theoretical basis for them to develop into a safe and effective novel root canal disinfectant.

Mitochondria-targeting folic acid-modified nanoplatform based on mesoporous carbon and a bioactive peptide for improved colorectal cancer treatment

Oral colon-targeted drug delivery systems (OCDDs) are designed to deliver the therapeutic agents to colonic disease sites to improve the effectiveness of drug treatment, increase bioavailability, and reduce systemic side effects and are beneficial for the treatment of colorectal cancer (CRC) and inflammatory bowel disease (IBD). However, concerns about the biosafety of OCDDs are increasing, and changes in the physiological environment of the gastrointestinal tract can affect the therapeutic efficacy of the drug. Herein, we report about an orally administered colon-accumulating mitochondria-targeted drug delivery nanoplatform (M27-39@FA-MCNs), which was synthesized using the small peptide, M27-39, and folic acid (FA)-modified mesoporous carbon nanoparticles (FA-MCNs). The phenolic resin polymerized with phloroglucinol and formaldehyde (PF) was used for fabricating MCNs using a one-step soft-template method. Folic acid (FA) can be covalently combined with chitosan-modified MCNs to obtain FA-MCNs. The M27-39@FA-MCNs were stable with a spherical morphology and an average diameter of 129 nm. The cumulative release rate of M27-39@FA-MCNs in the artificial gastric fluid (pH = 1.2) and intestinal fluid (pH = 6.8) for 6 h was 87.77%. This nanoplatform maintains the advantages of both FA and MCNs to improve the bioactivity of M27-39 with high drug accumulation in colorectal tumor tissues and the ease of excretion, thus ameliorating its biosafety and targetability. Furthermore, M27-39@FA-MCNs induced tumor-cell apoptosis and inhibited tumor growth by disrupting mitochondrial energy metabolism and regulating the mitochondrial apoptosis signaling pathway and immune inflammatory response. Thus, such a mitochondria-targeting FA-modified nanoplatform based on mesoporous carbon and a bioactive peptide may provide a precise strategy for CRC treatment. STATEMENT OF SIGNIFICANCE: In this study, we constructed an orally administered colon-accumulating mitochondria-targeted drug delivery nanoplatform (M27-39@FA-MCNs), which was synthesized using the small peptide (M27-39) and folic acid-modified mesoporous carbon nanoparticles (FA-MCNs). M27-39@FA-MCNs increased the targeting ability of M27-39 toward mitochondria and colon based on the properties of FA-MCNs; they also increased M27-39 accumulation and residence time in colon tumors. Oral administration of M27-39@FA-MCNs remarkably alleviated colorectal cancer (CRC) by targeting tumor cell mitochondria and interfering with the mitochondrial energy metabolism process, and inducing apoptosis related P53/Caspase-3 mitochondrial pathway activation. Therefore, M27-39@FA-MCNs may provide a safe and precise therapeutic strategy for CRC.

Spirulina platensis aqueous extracts ameliorate colonic mucosal damage and modulate gut microbiota disorder in mice with ulcerative colitis by inhibiting inflammation and oxidative stress

Ulcerative colitis (UC) is a chronic and recurrent inflammatory bowel disease (IBD) that has become a major gastroenterologic problem during recent decades. Numerous complicating factors are involved in UC development such as oxidative stress, inflammation, and microbiota disorder. These factors exacerbate damage to the intestinal mucosal barrier. Spirulina platensis is a commercial alga with various biological activity that is widely used as a functional ingredient in food and beverage products. However, there have been few studies on the treatment of UC using S. platensis aqueous extracts (SP), and the underlying mechanism of action of SP against UC has not yet been elucidated. Herein, we aimed to investigate the modulatory effect of SP on microbiota disorders in UC mice and clarify the underlying mechanisms by which SP alleviates damage to the intestinal mucosal barrier. Dextran sulfate sodium (DSS) was used to establish a normal human colonic epithelial cell (NCM460) injury model and UC animal model. The mitochondrial membrane potential assay 3-‍‍(4,5-dimethylthiazol-2-yl)-2,‍5-diphenyltetrazolium bromide (MTT) and staining with Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) and Hoechst 33258 were carried out to determine the effects of SP on the NCM460 cell injury model. Moreover, hematoxylin and eosin (H&E) staining, transmission electron microscopy (TEM), enzyme-linked immunosorbent assay (ELISA), quantitative real-time polymerase chain reaction (qPCR), western blot, and 16S ribosomal DNA (rDNA) sequencing were used to explore the effects and underlying mechanisms of action of SP on UC in C57BL/6 mice. In vitro studies showed that SP alleviated DSS-induced NCM460 cell injury. SP also significantly reduced the excessive generation of intracellular reactive oxygen species (ROS) and prevented mitochondrial membrane potential reduction after DSS challenge. In vivo studies indicated that SP administration could alleviate the severity of DSS-induced colonic mucosal damage compared with the control group. Inhibition of inflammation and oxidative stress was associated with increases in the activity of antioxidant enzymes and the expression of tight junction proteins (TJs) post-SP treatment. SP improved gut microbiota disorder mainly by increasing antioxidant enzyme activity and the expression of TJs in the colon. Our findings demonstrate that the protective effect of SP against UC is based on its inhibition of pro-inflammatory cytokine overproduction, inhibition of DSS-induced ROS production, and enhanced expression of antioxidant enzymes and TJs in the colonic mucosal barrier.

Total Flavonoids of Chuju Decrease Oxidative Stress and Cell Apoptosis in Ischemic Stroke Rats: Network and Experimental Analyses

Background: Pharmacological research results showed that total flavonoids of Chuju (TFCJ) could be used to treat acute myocardial ischemia and myocardial ischemia-reperfusion injury. In this study, we explored the protective effect of TFCJ on ischemic stroke (IS) in the IS rat model. We hypothesized that TFCJ might exert its neuroprotective effects by suppressing apoptosis and oxidative stress that are closely related to PI3K/Akt/mTOR signaling pathway. Method: TFCJ (10, 20, and 40 mg/kg) was administered for 7 days. Rats (260 ± 20 g) were subjected to middle cerebral artery occlusion (MCAO) for 2 h and reperfusion for 24 h. The neuroprotective effect of TFCJ was substantiated in terms of neurological deficits, oxidative stress (superoxide dismutase, glutathione peroxidase, catalase, and malondialdehyde), pathomorphological changes (HE staining and TUNEL staining), and neurobehavioral functions in the rats. Then, we employed network pharmacology to reveal the potential mechanism of TFCJ against IS. Western blot was used to determine the levels of PI3K/AKT/mTOR pathway proteins. The expression of BCL-2, BAX, and cleaved-Caspase-3 was also measured by Western blots and RT-PCR. Results: The histopathological assessment showed that TFCJ reduced MCAO-induced brain damage. Besides, TFCJ exerted a protective role in MCAO rats by alleviating cell apoptosis and oxidative stress. Network pharmacology showed that TFCJ might be used against IS through the PI3K/AKT signaling pathway. TFCJ reduced cell apoptosis and oxidative stress by increasing the level of p-AKT and p-mTOR in MCAO rats, while the effect of TFCJ was significantly reversed when applying LY294002 (PI3k inhibitor). Conclusion: These results indicated that TFCJ might decrease oxidative stress and apoptosis that are closely related to PI3K/Akt/mTOR pathway in IS. TFCJ is a promising authentic traditional Chinese medicine for the management of IS.

Biodistribution of Mesoporous Carbon Nanoparticles via Technetium-99m Radiolabelling after Oral Administration to Mice

The use of ordered mesoporous matrices, and in particular carbon-based mesoporous nanoparticles has shown great potential towards enhancing the bioavailability of orally administered drugs. Nevertheless, elucidation of the in vivo absorption, distribution, and excretion of such carriers is essential for understanding their behaviour, and radiolabelling provides a very useful way to track their occurrence inside the body. In this work, uniform spherical CMK-1-type ordered mesoporous carbon nanoparticles have been radiolabelled with Technetium-99m (99mTc) and traced after oral administration to mice. Ex vivo biodistribution studies showed that the radiolabelled nanoparticles accumulated almost exclusively in the gastrointestinal tract; complete elimination of the radiotracer was observed within 24 h after administration, with practically no uptake into other main organs. These findings along with the results from in vitro stability studies indicate that the spherical carbon nanoparticles examined could be safely used as drug carriers with minimal side effects, but also support the great value of radiolabelling methods for monitoring the particles' behaviour in vivo.

'Green' nanotherapeutics from tea leaves for orally targeted prevention and alleviation of colon diseases

Although synthesized nanotherapeutics (NTs) are attractive for the oral treatment of colon diseases, their clinical translations are constrained by the unsatisfactory therapeutic outcomes, potential adverse effects, and high cost of mass production. Here, we report the development of tea leaf-derived natural NTs with desirable particle sizes (140.0 nm) and negative surface charge (-14.6 mV). These natural exosome-like NTs were found to contain large amounts of lipids, some functional proteins, and many bioactive small molecules. Specifically, galactose groups on the surface of NTs could mediate their specific internalization by macrophages via galactose receptor-mediated endocytosis. Moreover, these NTs were able to reduce the production of reactive oxygen species, inhibit the expression of pro-inflammatory cytokines, and increase the amount of anti-inflammatory IL-10 secreted by macrophages. Orally administered NTs could efficiently inhibit the inflammatory bowel responses, restore disrupted colonic barriers and enhance the diversity and overall abundance of gut microbiota, thereby preventing or alleviating inflammatory bowel disease and colitis-associated colon cancer. The present study brings new insights to the facile application of a versatile and robust natural nanoplatform for the prevention and treatment of colon diseases.

Achyrophenols A-F: Polycyclic Polyphenol Lactone Skeletons and a Nor-Ursane-Type Triterpenoid from Achyrocline Satureioides

Two novel derivatives of 2-methyl-1-(2,3,4,6-tetrahydroxyphenyl)propan-1-one and (S)-2-methyl-1-(2,3,4,6-tetrahydroxyphenyl)butan-1-one (1 and 2), four novel six-membered lactone phenols (3-6), and a nor-ursane type triterpenoid (7) named Achroacid, were isolated from the aerial part of Achyrocline satureioides. The absolute configurations of 1-7 are presented by spectroscopic data and X-ray crystallographic analysis. A DP4plus evaluation was applied to determine the final stereochemistry for 1 and 2. The biosynthesis pathway of 1 and 2 was proposed. 1 has potential on anti-Gram-negative bacteria. Both 1 and 2 exhibited a significant impact on anti-H1299 cells. Compounds 3-7 showed moderate cancer cell lethality and significant anti-inflammatory activities.

Phytochemicals as regulators of Th17/Treg balance in inflammatory bowel diseases

Inflammatory bowel disease (IBD) is a chronic inflammatory intestinal disorder that is difficult to cure and characterized by periods of relapse. To face the challenges of limited treatment strategies and drawbacks of conventional medications, developing new and promising strategies as well as safe and effective drugs for treatment of IBD has become an urgent demand for clinics. The imbalance of Th17/Treg is a crucial event for the development of IBD, and studies have verified that correcting the imbalance of Th17/Treg is an effective strategy for preventing and treating IBD. Recently, a growing body of studies has indicated that phytochemicals derived from natural products are potent regulators of Th17/Treg, and exert preferable protective benefits against colonic inflammation. In this review, the great potential of anti-colitis agents derived from natural products through targeting Th17/Treg cells and their action mechanisms for the treatment or prevention of IBD in recent research is summarized, which may help further the development of new drugs for IBD treatment.

Recent Progress in the Diagnosis and Precise Nanocarrier-Mediated Therapy of Inflammatory Bowel Disease

The effective colon drug delivery remains to be an international frontier research in inflammatory bowel disease (IBD) therapy. The exploration and research of nanocarrier-based nanomedicine with great potential brings new opportunities for IBD therapy and diagnoses. Functional nanocarriers with varying morphology and characteristics can not only effectively avoid the destruction of the complex gastrointestinal (GI) tract microenvironment but also endow drugs with target therapy and improved bioavailability, thus elevating therapeutic efficacy. In this review, we illustrated several challenges in IBD therapy, then emphasis on some latest research progress of nanoparticles based therapy of oral administration, rectal administration and parenteral administration, as well as IBD diagnoses. Finally, we described the future perspective of nanocarriers in the treatment and diagnoses of IBD.