Phillygenin Attenuated Colon Inflammation and Improved Intestinal Mucosal Barrier in DSS-induced Colitis Mice via TLR4/Src Mediated MAPK and NF-κB Signaling Pathways

Shuangdan Jiedu Decoction improved LPS-induced acute lung injury by regulating both cGAS-STING pathway and inflammasome

ETHNOPHARMACOLOGICAL RELEVANCE

Shuangdan Jiedu Decoction (SJD) is a formula composed of six Chinese herbs with heat-removing and detoxifying, antibacterial and anti-inflammatory effects, which is clinically used in the therapy of various inflammatory diseases of the lungs including COVID-19, but the therapeutic material basis of its action as well as its molecular mechanism are still unclear.

AIM OF THE STUDY

The study attempted to determine the therapeutic effect of SJD on LPS-induced acute lung injury (ALI), as well as to investigate its mechanism of action and assess its therapeutic potential for the cure of inflammation-related diseases in the clinical setting.

MATERIALS AND METHODS

We established an ALI model by tracheal drip LPS, and after the administration of SJD, we collected the bronchoalveolar lavage fluid and lung tissues of mice and examined the expression of inflammatory factors in them. In addition, we evaluated the effects of SJD on the cyclic guanosine monophosphate-adenosine monophosphate synthase -stimulator of interferon genes (cGAS-STING) and inflammasome by immunoblotting, and real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

We demonstrated that SJD was effective in alleviating LPS-induced ALI by suppressing the levels of pro-inflammatory cytokines in the bronchoalveolar lavage fluid (BALF), improving the level of lung histopathology and the number of neutrophils, as well as decreasing the inflammatory factor-associated gene expression. Importantly, we found that SJD could inhibit multiple stimulus-driven activation of cGAS-STING and inflammasome. Further studies showed that the Chinese herbal medicine in SJD had no influence on the cGAS-STING pathway and inflammasome alone at the formulated dose. By increasing the concentration of these herbs, we observed inhibitory effects on the cGAS-STING pathway and inflammasome, and the effect exerted was maximal when the six herbs were combined, dicating that the synergistic effects among these herbs plays a crucial role in the anti-inflammatory effects of SJD.

CONCLUSIONS

Our research demonstrated that SJD has a favorable protective effect against ALI, and its mechanism of effect may be associated with the synergistic effect exerted between six Chinese medicines to inhibit the cGAS-STING and inflammasome abnormal activation. These results are favorable for the wide application of SJD in the clinic as well as for the development of drugs for ALI from herbal formulas.

The phytochemistry, pharmacology, pharmacokinetics, quality control, and toxicity of Forsythiae Fructus: An updated systematic review

Forsythiae Fructus (FF), the dried fruit of F. suspensa, is commonly used to treat fever, inflammation, etc in China or other Asian countries. FF is usually used as the core herb in traditional Chinese medicine preparations for the treatment of influenza, such as Shuang-huang-lian oral liquid and Yin-qiao powder, etc. Since the wide application and core role of FF, its research progress was summarized in terms of traditional uses, phytochemistry, pharmacology, pharmacokinetics, quality control, and toxicity. Meanwhile, the anti-influenza substances and mechanism of FF were emphasized. Till now, a total of 290 chemical components are identified in F. suspensa, and among them, 248 components were isolated and identified from FF, including 42 phenylethanoid glycosides, 48 lignans, 59 terpenoids, 14 flavonoids, 3 steroids, 24 cyclohexyl ethanol derivatives, 14 alkaloids, 26 organic acids, and 18 other types. FF and their pure compounds have the pharmacological activities of anti-virus, anti-inflammation, anti-oxidant, anti-bacteria, anti-tumor, neuroprotection, hepatoprotection, etc. Inhibition of TLR7, RIG-I, MAVS, NF-κB, MyD88 signaling pathway were the reported anti-influenza mechanisms of FF and phenylethanoid glycosides and lignans are the main active groups. However, the bioavailability of phenylethanoid glycosides and lignans of FF in vivo was low, which needed to be improved. Simultaneously, the un-elucidated compounds and anti-influenza substances of FF strongly needed to be explored. The current quality control of FF was only about forsythoside A and phillyrin, more active components should be taken into consideration. Moreover, there are no reports of toxicity of FF yet, but the toxicity of FF should be not neglected in clinical applications.

Taenia solium cysticerci's extracellular vesicles Attenuate the AKT/mTORC1 pathway for Alleviating DSS-induced colitis in a murine model

The excretory-secretory proteome plays a pivotal role in both intercellular communication during disease progression and immune escape mechanisms of various pathogens including cestode parasites like Taenia solium. The cysticerci of T. solium causes infection in the central nervous system known as neurocysticercosis (NCC), which affects a significant population in developing countries. Extracellular vesicles (EVs) are 30-150-nm-sized particles and constitute a significant part of the secretome. However, the role of EV in NCC pathogenesis remains undetermined. Here, for the first time, we report that EV from T. solium larvae is abundant in metabolites that can negatively regulate PI3K/AKT pathway, efficiently internalized by macrophages to induce AKT and mTOR degradation through auto-lysosomal route with a prominent increase in the ubiquitination of both proteins. This results in less ROS production and diminished bacterial killing capability among EV-treated macrophages. Due to this, both macro-autophagy and caspase-linked apoptosis are upregulated, with a reduction of the autophagy substrate sequestome 1. In summary, we report that T. solium EV from viable cysts attenuates the AKT-mTOR pathway thereby promoting apoptosis in macrophages, and this may exert immunosuppression during an early viable stage of the parasite in NCC, which is primarily asymptomatic. Further investigation on EV-mediated immune suppression revealed that the EV can protect the mice from DSS-induced colitis and improve colon architecture. These findings shed light on the previously unknown role of T. solium EV and the therapeutic role of their immune suppression potential.

Cordyceps militaris Extract and Cordycepin Alleviate Oxidative Stress, Modulate Gut Microbiota and Ameliorate Intestinal Damage in LPS-Induced Piglets

Cordycepin is considered a major bioactive component in Cordyceps militaris extract. This study was performed to evaluate the ameliorative effect of Cordyceps militaris extract (CME) and cordycepin (CPN) supplementation on intestinal damage in LPS-challenged piglets. The results showed that CPN or CME supplementation significantly increased the villus height (p < 0.01) and villus height/crypt depth ratio (p < 0.05) in the jejunum and ileum of piglets with LPS-induced intestinal inflammation. Meanwhile, CPN or CME supplementation alleviated oxidative stress and inflammatory responses by reducing the levels of MDA (p < 0.05) and pro-inflammatory cytokines in the serum. Additionally, supplementation with CPN or CME modulated the structure of the intestinal microbiota by enriching short-chain fatty acid-producing bacteria, and increased the level of butyrate (p < 0.05). The RNA-seq results demonstrated that CME or CPN altered the complement and coagulation-cascade-related genes (p < 0.05), including upregulating gene KLKB1 while downregulating the genes CFD, F2RL2, CFB, C4BPA, F7, C4BPB, CFH, C3 and PROS1, which regulate the complement activation involved in inflammatory and immune responses. Correlation analysis further demonstrated the potential relation between the gut microbiota and intestinal inflammation, oxidative stress, and butyrate in piglets. In conclusion, CPN or CME supplementation might inhibit LPS-induced inflammation and oxidative stress by modulating the intestinal microbiota and its metabolite butyrate in piglets.

Research advancements and perspectives of inflammatory bowel disease: A comprehensive review

Inflammatory bowel disease (IBD) is a chronic inflammatory disease with increasing incidence, such as Crohn's disease and ulcerative colitis. The accurate etiology and pathogenesis of IBD remain unclear, and it is generally believed that it is related to genetic susceptibility, gut microbiota, environmental factors, immunological abnormalities, and potentially other factors. Currently, the mainstream therapeutic drugs are amino salicylic acid agents, corticosteroids, immunomodulators, and biological agents, but the remission rates do not surpass 30-60% of patients in a real-life setting. As a consequence, there are many studies focusing on emerging drugs and bioactive ingredients that have higher efficacy and long-term safety for achieving complete deep healing. This article begins with a review of the latest, systematic, and credible summaries of the pathogenesis of IBD. In addition, we provide a summary of the current treatments and drugs for IBD. Finally, we focus on the therapeutic effects of emerging drugs such as microRNAs and lncRNAs, nanoparticles-mediated drugs and natural products on IBD and their mechanisms of action.

Bicarbonate secretion and acid/base sensing by the intestine

The transport of bicarbonate across the enterocyte cell membrane regulates the intracellular as well as the luminal pH and is an essential part of directional fluid movement in the gut. Since the first description of "active" transport of HCO3- ions against a concentration gradient in the 1970s, the fundamental role of HCO3- transport for multiple intestinal functions has been recognized. The ion transport proteins have been identified and molecularly characterized, and knockout mouse models have given insight into their individual role in a variety of functions. This review describes the progress made in the last decade regarding novel techniques and new findings in the molecular regulation of intestinal HCO3- transport in the different segments of the gut. We discuss human diseases with defects in intestinal HCO3- secretion and potential treatment strategies to increase luminal alkalinity. In the last part of the review, the cellular and organismal mechanisms for acid/base sensing in the intestinal tract are highlighted.

Traditional herbal pair Portulacae Herba and Granati Pericarpium alleviates DSS-induced colitis in mice through IL-6/STAT3/SOCS3 pathway

BACKGROUND

Portulacae Herba and Granati Pericarpium pair (PGP) is a traditional Chinese herbal medicine treatment for colitis, clinically demonstrating a relatively favorable effect on relieving diarrhea and abnormal stools. However, the underlying mechanism remain uncertain.

PURPOSE

The present study intends to evaluate the efficacy of PGP in treating colitis in mice and investigate its underlying mechanism.

METHODS

The protective effect of PGP against colitis was determined by monitoring body weight, colon length, colon weight, and survival rate in mice. Colonic inflammation was assessed by serum cytokine levels, colonic H&E staining, and local neutrophil infiltration. The reversal of intestinal epithelial barrier damage by PGP was subsequently analyzed with Western blot and histological staining. Furthermore, RNA-seq analysis and molecular docking were performed to identify potential pathways recruited by PGP. Following the hints of the transcriptomic results, the role of PGP through the IL-6/STAT3/SOCS3 pathway in DSS-induced colitis mice was verified by Western blot.

RESULTS

DSS-induced colitis in mice was significantly curbed by PGP treatment. PGP treatment significantly mitigated DSS-induced colitis in mice, as evidenced by improvements in body weight, DAI severity, survival rate, and inflammatory cytokines levels in serum and colon. Moreover, PGP treatment up-regulated the level of Slc26a3, thereby increasing the expressions of the tight junction/adherens junction proteins ZO-1, occludin and E-cadherin in the colon. RNA-seq analysis revealed that PGP inhibits the IL-6/STAT3/SOCS3 pathway at the transcriptional level. Molecular docking indicated that the major components of PGP could bind tightly to the proteins of IL-6 and SOCS3. Meanwhile, the result of Western blot revealed that the IL-6/STAT3/SOCS3 pathway was inhibited at the protein level after PGP administration.

CONCLUSION

PGP could alleviate colonic inflammation and reverse damage to the intestinal epithelial barrier in DSS-induced colitis mice. The underlying mechanism involves the inhibition of the IL-6/STAT3/SOCS3 pathway.

An Update on the Role and Potential Molecules in Relation to Ruminococcus gnavus in Inflammatory Bowel Disease, Obesity and Diabetes Mellitus

Ruminococcus gnavus (R. gnavus) is a gram-positive anaerobe commonly resides in the human gut microbiota. The advent of metagenomics has linked R. gnavus with various diseases, including inflammatory bowel disease (IBD), obesity, and diabetes mellitus (DM), which has become a growing area of investigation. The initial focus of research primarily centered on assessing the abundance of R. gnavus and its potential association with disease presentation, taking into account variations in sample size, sequencing and analysis methods. However, recent investigations have shifted towards elucidating the underlying mechanistic pathways through which R. gnavus may contribute to disease manifestation. In this comprehensive review, we aim to provide an updated synthesis of the current literature on R. gnavus in the context of IBD, obesity, and DM. We critically analyze relevant studies and summarize the potential molecular mediators implicated in the association between R. gnavus and these diseases. Across numerous studies, various molecules such as methylation-controlled J (MCJ), glucopolysaccharides, ursodeoxycholic acid (UDCA), interleukin(IL)-10, IL-17, and capric acid have been proposed as potential contributors to the link between R. gnavus and IBD. Similarly, in the realm of obesity, molecules such as hydrogen peroxide, butyrate, and UDCA have been suggested as potential mediators, while glycine ursodeoxycholic acid (GUDCA) has been implicated in the connection between R. gnavus and DM. Furthermore, it is imperative to emphasize the necessity for additional studies to evaluate the potential efficacy of targeting pathways associated with R. gnavus as a viable strategy for managing these diseases. These findings have significantly expanded our understanding of the functional role of R. gnavus in the context of IBD, obesity, and DM. This review aims to offer updated insights into the role and potential mechanisms of R. gnavus, as well as potential strategies for the treatment of these diseases.

The antimicrobial peptide Abaecin alleviates colitis in mice by regulating inflammatory signaling pathways and intestinal microbial composition

Abaecin is a natural antimicrobial peptide (AMP) rich in proline from bees. It is an important part of the innate humoral immunity of bees and has broad-spectrum antibacterial ability. This study aimed to determine the effect of Abaecin on dextran sulfate sodium (DSS) -induced ulcerative colitis (UC) in mice and to explore its related mechanisms. Twenty-four mice with similar body weight were randomly divided into 4 groups. 2.5% DSS was added to drinking water to induce colitis in mice. Abaecin and PBS were administered rectally on the third, fifth, and seventh days of the experimental period. The results showed that Abaecin significantly alleviated histological damage and intestinal mucosal barrier damage caused by colitis in mice, reduced the concentration of pro-inflammatory cytokines IL-1β, IL-6, TNF-α, IFN-γ, and the phosphorylation of NF-κB / MAPK inflammatory signaling pathway proteins, and improved the composition of intestinal microorganisms. These findings suggest that Abaecin may have potential prospects for the treatment of UC.

Oral administration of LfcinB alleviates DSS-induced colitis by improving the intestinal barrier and microbiota

Ulcerative colitis (UC) is a kind of inflammatory bowel disease (IBD) that often recurs and is difficult to cure, and no drugs with few side effects are available to treat this disease. LfcinB is a small molecular peptide obtained by the hydrolysis of bovine lactoferrin in the digestive tract of animals. It has strong antibacterial and anti-inflammatory activities. However, direct evidence that LfcinB improves the condition of colitis in mice is rarely reported. In this study, UC was induced in mice by adding 2.5% dextran sulfate (DSS) to drinking water and LfcinB was orally administered. The results showed that oral administration of LfcinB improved colonic tissue damage and inflammatory cell infiltration, increased the expression of tight junction proteins, and down-regulated the phosphorylation of proteins related to the NF-κB/MAPK inflammatory signalling pathway in mice. It also significantly suppressed the relative abundance of potentially pathogenic bacteria (Bacteroides, Barnesiella and Escherichia) in the intestinal flora. In conclusion, oral administration of LfcinB significantly alleviated DSS-induced UC. This may be related to the regulation of inflammatory signalling pathways and gut microbial composition by LfcinB.

Synergistic anti-infectious bronchitis virus activity of Phillygenin combined Baicalin by modulating respiratory microbiota and improving metabolic disorders

Phillygenin (PHI) and Baicalin (Bai) are the major chemical ingredients extracted from Forsythia suspensa and Scutellaria baicalensis, respectively. The mixture of Forsythia suspensa and Scutellaria baicalensis according to the theories of Traditional Chinese Veterinary Medicine, compounded formulation can effectively exert heat-clearing and detoxifying effect, but the synergistic anti-IBV activity of PHI combined with Bai was unclear. Here, the protection of PHI combined with Bai on avian infectious bronchitis virus (IBV) M41 infection and the change of respiratory microbiota and metabolomics profiles in broilers that infected with IBV were investigated. According to the experimental findings, the combination of PHI and Bai effectively alleviated broilers' slowing-growth weight and respiratory symptoms. This was accompanied by a reduction in viral copies and histopathological changes, as well as an increase of antiviral protein (G3BP1) level in tracheas and anti-IBV antibody levels in serum. In addition, 16s RNA sequencing revealed that IBV infection significantly changed respiratory microbiota composition at different taxonomic levels and respiratory metabolism composition in broilers. Interestingly, PHI combined with Bai modulated the composition of respiratory microfloras, especially the abundance of Firmicutes and Lactobacillaceae were upregulated, as well as the abundance of Proteobacteria was downregulated. The metabolomics results indicated that PHI combined with Bai involved in glucose, lipids, amino acids and nucleotide metabolism during IBV infection. In summary, PHI combined with Bai exhibited a synergistic effect on preventing infectious bronchitis (IB), with the protection being closely associated with the composition of respiratory microbiota and metabolites. Therefore, adding the mixture of PHI and Bai to the chicken drinking water is recommended to prevent and control IB in clinical.

Exploration of the Mechanisms Underlying Yu's Enema Formula in Treating Ulcerative Colitis by Blocking the RhoA/ROCK Pathway based on Network Pharmacology, High-performance Liquid Chromatography Analysis, and Experimental Verification

BACKGROUND

The traditional Chinese medicine formula, Yu's Enema Formula (YEF), has demonstrated potential in the treatment of Ulcerative Colitis (UC).

OBJECTIVE

This study aimed to unveil the anti-UC mechanisms of YEF.

METHODS

Utilizing public databases, we obtained YEF and UC-related targets. GO and KEGG analyses were conducted via clusterProfiler and Reactome. The STRING database facilitated the construction of the PPI network, and hub targets were selected using cytoHubba. We used R software for differential expression and correlation analyses, and molecular docking was performed with PyMOL and AutoDock. HPLC analysis identified the compounds in YEF. For in vivo validation, a UC rat model was employed.

RESULTS AND DISCUSSION

495 YEF-UC overlapping targets were identified. GO and KEGG analyses indicated enrichment in exogenous stimuli response, peptide response, positive MAPK cascade regulation, interleukin- related signaling, and the TLR4 cascade. Hub targets included CTNNB1, JUN, MAPK1, MAPK3, SRC, STAT3, TLR4, TP53, and RELA, which were often interconnected. Molecular docking revealed quercetin's strong binding affinity with CTNNB1, MAPK1, MAPK3, SRC, STAT3, TLR4, and TP53, consistent with HPLC analysis. In vivo experiments suggested that YEF has the potential to alleviate UC symptoms and protect the intestinal mucosal barrier by inhibiting the RhoA/ROCK pathway.

CONCLUSION

YEF may safeguard the intestinal mucosal barrier in UC by targeting CTNNB1, MAPK1, MAPK3, SRC, STAT3, TLR4, and TP53, while blocking the RhoA/ROCK pathway.

Network pharmacology and molecular docking reveal potential mechanism of esculetin in the treatment of ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease of the colonic mucosa. Esculetin is a type of natural coumarin that has many pharmacological activities such as antioxidant, anticancer, anti-inflammatory, etc. A previous study showed that esculetin improved intestinal inflammation and reduced serum proinflammatory cytokines in UC. The present study aimed to utilize network pharmacology and molecular docking to explore the potential mechanism of esculetin against UC. The potential gene targets of esculetin were predicted through SwissTargetPrediction and Super-PRED web servers. UC-related genes were obtained from DisGeNet, OMIM, and GeneCards databases. The overlap between gene targets of esculetin and UC-related genes were identified as the potential targets of esculetin against UC. The interaction between these overlapping genes was analyzed by the STRING database and the core genes were identified by Cytoscape platform. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of the core genes were then performed. And the results of these analyses were further confirmed through molecular docking. A total of 50 overlapping genes were identified as the potential action targets of esculetin against UC. Among them, 10 genes (AKT1, STAT1, CCND1, SRC, PTGS2, EGFR, NFKB1, ESR1, MMP9, SERPINE1) were finally identified as the core genes. The Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis results showed that the top signaling pathway associated with the core genes of esculetin against UC was the prolactin (PRL) signaling pathway. Molecular docking results showed that esculetin has a strong binding affinity to the core genes, as well as PRL and prolactin receptor. This study suggests that esculetin may have a crucial impact on UC through the PRL signaling pathway and provides insights into the potential mechanism of esculetin in the treatment of UC, which may shed light on the mechanism and treatment of UC.

Forsythia suspensa (Thunb.) Vahl extract ameliorates ulcerative colitis via inhibiting NLRP3 inflammasome activation through the TLR4/MyD88/NF-κB pathway

BACKGROUND

Ulcerative colitis (UC), a chronic inflammatory disease, is caused by abnormal immune system reactions resulting in inflammation and ulcers in the large intestine. Phillygenin (PHI) is a natural compound found in Forsythia suspensa (Thunb.) Vahl, which is known for its antipyretic, anti-inflammatory, antiobesity, and other biological activities. However, the therapeutic role and molecular mechanisms of PHI on UC are still insufficiently researched.

METHODS

In this study, dextran sulfate sodium (DSS) and 2.5% 2,4,6-trinitro-Benzenesulfonic acid (TNBS)-induced acute UC were used to investigate the therapeutic effects of PHI. We evaluated the effects of PHI on disease activity index (DAI), body weight, mortality, intestinal mucosal barrier, cytokine secretion, and macrophage infiltration into colon tissue using various techniques such as flow cytometry, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), RT-qPCR, and Western blot analysis.

RESULTS

Our findings revealed that PHI has therapeutic properties in UC treatment. PHI was able to maintain body weight, reduce DAI and mortality, restore the intestinal mucosal barrier, and inhibit cytokine secretion. Flow cytometry assay and immunofluorescence indicated that PHI reduces macrophage infiltration into colon tissue. Mechanistically, PHI may exert anti-inflammatory effects by downregulating the TLR4/MyD88/NF-κB pathway and inhibiting the activation of NLRP3 inflammasome.

CONCLUSION

In conclusion, PHI possesses significant anti-inflammatory properties and is expected to be a potential drug for UC treatment. Our study delves into the underlying mechanisms of PHI therapy and highlights the potential for further research in developing PHI-based treatments for UC.

A comprehensive review on pharmacological, toxicity, and pharmacokinetic properties of phillygenin: Current landscape and future perspectives

Forsythiae Fructus is a traditional Chinese medicine frequently in clinics. It is extensive in the treatment of various inflammation-related diseases and is renowned as 'the holy medicine of sores'. Phillygenin (C21H24O6, PHI) is a component of lignan that has been extracted from Forsythiae Fructus and exhibits notable biological activity. Modern pharmacological studies have confirmed that PHI demonstrates significant activities in the treatment of various diseases, including inflammatory diseases, liver diseases, cancer, bacterial infection and virus infection. Therefore, this review comprehensively summarizes the pharmacological effects of PHI up to June 2023 by searching PubMed, Web of Science, Science Direct, CNKI, and SciFinder databases. According to the data, PHI shows remarkable anti-inflammatory, antioxidant, hepatoprotective, antitumour, antibacterial, antiviral, immunoregulatory, analgesic, antihypertensive and vasodilatory activities. More importantly, NF-κB, MAPK, PI3K/AKT, P2X7R/NLRP3, Nrf2-ARE, JAK/STAT, Ca2+-calcineurin-TFEB, TGF-β/Smads, Notch1 and AMPK/ERK/NF-κB signaling pathways are considered as important molecular targets for PHI to exert these pharmacological activities. Studies of its toxicity and pharmacokinetic properties have shown that PHI has very low toxicity, incomplete absorption in vivo and low oral bioavailability. In addition, the physico-chemical properties, new formulations, derivatives and existing challenges and prospects of PHI are also reviewed and discussed in this paper, aiming to provide direction and rationale for the further development and clinical application of PHI.