Indigo naturalis is effective even in treatment-refractory patients with ulcerative colitis: a post hoc analysis from the INDIGO study

Evaluation of Indigo Naturalis Prepared Using a Novel Method: Therapeutic Effects on Experimental Ulcerative Colitis in Mice

Background/Objectives: Indigo naturalis (IN) is a traditional Chinese medicine concocted from medicinal plants such as Baphicacanthus cusia (Nees) Bremek. IN has multifaceted pharmacological activities. Recent research highlights the remarkable efficacy of IN in treating ulcerative colitis (UC). This study investigates the efficacy of Indigo Naturalis prepared using a novel method (NIN) in ameliorating UC. Methods: We have developed a new IN processing technology without the use of lime. Correspondingly, the content of active ingredients has relatively increased in NIN. In this study, dextran sulfate sodium salt (DSS) induced UC models among male KM mice, and the protective effects of NIN on UC were verified. Results: NIN could significantly improve weight loss, diarrhea and prolapse, bloody stools, elevated Disease Activity Index (DAI) and alleviate the colitis symptoms of mice; it could also improve the shortening of colon, disappearance of intestinal crypts, epithelial cell destruction and inflammatory infiltration caused by UC; and it could also significantly reduce the Histological Index (HI). In addition, NIN relieved the inflammatory response by decreasing the content of pro-inflammatory cytokines TNF-α and IL-1β and elevating the content of anti-inflammatory cytokines IL-10 and IL-22. It also restored the intestinal mucosal barrier by increasing the level of MUC2 protein expression at the site of colonic injury. Conclusions: The significant effects of NIN on UC were verified for the first time, suggesting that NIN was worth further developing into a novel therapeutic drug and, necessarily, further safety evaluations and comparisons with traditional IN will help in the application of NIN.

Modulation of blood-tumor barrier transcriptional programs improves intratumoral drug delivery and potentiates chemotherapy in GBM

Efficient drug delivery to glioblastoma (GBM) is a major obstacle as the blood-brain barrier (BBB) and the blood-tumor barrier (BTB) prevent passage of the majority of chemotherapies into the brain. Here, we identified a transcriptional 12-gene signature associated with the BTB in GBM. We identified CDH5 as a core molecule in this set and confirmed its expression in GBM vasculature using transcriptomics and immunostaining of patient specimens. The indirubin-derivative, 6-bromoindirubin acetoxime (BIA), down-regulates CDH5 and other BTB signature genes, causing endothelial barrier disruption in vitro and in murine GBM xenograft models. Treatment with BIA increased intratumoral cisplatin accumulation and potentiated DNA damage by targeting DNA repair pathways. Last, using an injectable BIA nanoparticle formulation, PPRX-1701, we significantly improved cisplatin efficacy in murine GBM. Our work reveals potential targets of the BTB and the bifunctional properties of BIA as a BTB modulator and a potentiator of chemotherapy, supporting its further development.

Clinical efficacy and future application of indigo naturalis in the treatment of ulcerative colitis

ETHNOPHARMACOLOGICAL RELEVANCE

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by non-specific inflammation. Managing UC presents significant challenges due to its chronic nature and high recurrence rates. Indigo naturalis has emerged as a potential therapeutic agent in clinical UC treatment, demonstrating advantages in alleviating refractory UC and maintaining remission periods compared to other therapeutic approaches.

AIM OF REVIEW

This review aims to elucidate the potential mechanisms underlying the therapeutic effects of indigo naturalis in UC treatment, assess its clinical efficacy, advantages, and limitations, and provide insights into methods and strategies for utilizing indigo naturalis in UC management.

MATERIALS AND METHODS

Comprehensive data on indigo naturalis were collected from reputable online databases including PubMed, GreenMedical, Web of Science, Google Scholar, China National Knowledge Infrastructure Database, and National Intellectual Property Administration.

RESULTS

Clinical studies have demonstrated that indigo naturalis, either alone or in combination with other drugs, yields favorable outcomes in UC treatment. Its mechanisms of action involve modulation of the AHR receptor, anti-inflammatory properties, regulation of intestinal flora, restoration of the intestinal barrier, and modulation of immunity. Despite its efficacy in managing refractory UC and prolonging remission periods, indigo naturalis treatment is associated with adverse reactions, quality variations, and inadequate pharmacokinetic investigations.

CONCLUSION

The therapeutic effects of indigo naturalis in UC treatment are closely linked to its ability to regulate the AHR receptor, exert anti-inflammatory effects, mcodulate intestinal flora, restore the intestinal barrier, and regulate immunity. Addressing the current shortcomings, including adverse reactions, quality control issues, and insufficient pharmacokinetic data, is crucial for optimizing the clinical utility of indigo naturalis in UC management. By refining patient-centered treatment strategies, indigo naturalis holds promise for broader application in UC treatment, thereby alleviating the suffering of UC patients.

Qingchang suppository ameliorates mucosal inflammation in ulcerative colitis by inhibiting the differentiation and effector functions of Th1 and Th17 cells

ETHNOPHARMACOLOGICAL RELEVANCE

Qing Chang Suppository (QCS), a traditional Chinese medicine formula, has been shown to effectively alleviate mucosal inflammation in patients with ulcerative colitis (UC). While the mechanism of QCS appears to be related to the regulation of CD4+T cell subset responses, direct evidence demonstrating that QCS inhibits Th1 and Th17 cell activation in UC (particularly based on human data) remains lacking. Additionally, the precise mechanisms through which QCS affects these cells have yet to be fully elucidated.

AIM OF STUDY

This study aimed to investigate the effects of QCS on Th1 and Th17 cell responses in UC and to explore the underlying mechanisms.

MATERIALS AND METHODS

Twenty-eight patients with mild-to-moderate UC were recruited and treated with QCS for 12 weeks. Symptoms were assessed every two weeks, with sigmoidoscopies performed at baseline and at week 12. Intestinal mucosal biopsies and peripheral blood (PB) were collected at these time points. At the end of the trial, patients were categorized into responder and non-responder groups based on a modified Mayo disease activity index score. Healthy controls (HCs) were defined as subjects without IBD or colorectal carcinoma but with colon polyps. The frequencies of IFN-γ+CD4+T cells and IL-17A+CD4+T cells in PB and colonic mucosa were measured using flow cytometry. The expression levels and localization of T-bet, RORγT, IFN-γ, TNF-α, and IL-17A were determined via immunofluorescence, and JNK signaling activation was assessed through immunoblotting and immunohistochemistry. All parameters were compared across the three groups.

RESULTS

At week 12, responders showed a significant reduction in colonic mucosal inflammation compared to baseline, accompanied by decreased frequencies of IFN-γ+CD4+T and IL-17A+CD4+ T cells in both PB and the colonic epithelial layer. Notably, Th1 and Th17 cell activity around intestinal epithelial cells (IECs) was nearly undetectable, as evidenced by the diminished expression of T-bet, RORγT, IFN-γ, TNF-α, and IL-17A. Additionally, JNK phosphorylation in these cells was significantly reduced. In contrast, non-responders exhibited no meaningful improvement; colonic pathology remained unchanged, and elevated levels of IFN-γ+CD4+T and IL-17A+CD 4+T cells persisted in both the PB and colonic epithelial layer. The presence of Th1 and Th17 cells and their associated cytokines around IECs remained substantial, and there was no significant change in JNK activation.

CONCLUSION

QCS attenuates mucosal inflammation in UC patients by inhibiting the differentiation and effector functions of Th1 and Th17 cells, primarily through the regulation of the JNK signaling pathway.

Selected Use of Complementary and Alternative Medicine (CAM) Agents in IBD

PURPOSE OF REVIEW

Inflammatory bowel disease (IBD) can cause significant psychological, physical, and economic burdens on patients and healthcare systems. Studies show over one-fifth of patients will seek nontraditional methods of treatment for managing their symptoms. Understanding the benefits - and potential harms - of these therapies is important to provide holistic and evidence-based care to our IBD patients.

RECENT FINDINGS

In this review, we present several studied herbal therapies for the management of both Crohn's disease and ulcerative colitis. These include cannabinoids, Tripterygium wilfordii, Chios mastic gum, Boswellia serrata, Indigo Naturalis, curcumin, resveratrol, and Zingiber officinale. While these herbal remedies have been shown to have anti-inflammatory effects and positive outcomes in IBD patients, larger scale studies are lacking and the use may be limited by bioavailability, lack of standardization of formulations, and adverse reactions. In reviewing the literature, we discuss the current data available including benefits, adverse reactions, and considerations for use surrounding several of the more common herbal remedies used for IBD.

Indigo naturalis as a potential drug in the treatment of ulcerative colitis: a comprehensive review of current evidence

CONTEXT

Ulcerative colitis (UC) is an intractable inflammatory bowel disease that threatens the health of patients. The limited availability of therapeutic strategies makes it imperative to explore more efficient and safer drugs. Indigo naturalis (IN) is a traditional Chinese medicine that possesses many pharmacological activities, including anti-inflammatory, antioxidant, and immunomodulatory activities. The treatment potential of IN for UC has been proven by numerous preclinical and clinical studies in recent years.

OBJECTIVE

This article provides a comprehensive review of the utility and potential of IN in the treatment of UC.

METHODS

'Indigo naturalis' 'Qing dai' 'Qingdai' 'Ulcerative colitis' and 'UC' are used as the keywords, and the relevant literature is collected from online databases (Elsevier, PubMed, and Web of Science).

RESULTS AND CONCLUSION

Indirubin, indigo, isatin, tryptanthrin, and β-sitosterol are considered the key components in the treatment of UC with IN. Both preclinical and clinical studies support the efficacy of IN for UC, especially in severe UC or in those who do not respond to or have poor efficacy with existing therapies. The mechanisms of IN for UC are associated with the aryl hydrocarbon receptor pathway activation, immune regulation, oxidative stress inhibition, and intestinal microbial modulation. However, the clinical use of IN has the risks of adverse events such as pulmonary hypertension, which suggests the necessity for its rational application. As a potential therapeutic agent for UC that is currently receiving more attention, the clinical value of IN has been initially demonstrated and warrants further evaluation.

Clinical outcomes of patients with remitting ulcerative colitis after discontinuation of indigo naturalis

Indigo naturalis is an effective treatment for ulcerative colitis. However, long-term use of indigo naturalis causes adverse events, such as pulmonary hypertension. The natural history of patients with ulcerative colitis who discontinued indigo naturalis after induction therapy is unknown. Moreover, the clinical features of patients who relapsed within 52 weeks after the discontinuation of indigo naturalis are unclear. This study aimed to assess the clinical outcomes of patients with ulcerative colitis after discontinuation of indigo naturalis and to identify potential markers responsible for relapse. This single-center retrospective study investigated the follow-up of 72 patients who achieved a clinical response 8 weeks after indigo naturalis treatment. We observed relapse in patients with ulcerative colitis after the discontinuation of indigo naturalis. We analyzed the factors predicting long-term outcomes after discontinuation of indigo naturalis. Relapse was observed in 24%, 57%, and 71% of patients at 8, 26, and 52 weeks, respectively. There were no predictive markers in patients who relapsed within 52 weeks after the discontinuation of indigo naturalis. The ulcerative colitis relapse rate after indigo naturalis discontinuation was high. Follow-up treatment is required after the discontinuation of indigo naturalis in patients with ulcerative colitis.

The double-edged sword effect of indigo naturalis

Indigo naturalis (IN) is a dried powder derived from plants such as Baphicacanthus cusia (Neeks) Bremek., Polygonum tinctorium Ait. and Isatis indigotica Fork. It has a historical application as a dye in ancient India, Egypt, Africa and China. Over time, it has been introduced to China and Japan for treatment of various ailments including hemoptysis, epistaxis, chest discomfort, and aphtha. Clinical and pre-clinical studies have widely demonstrated its promising effects on autoimmune diseases like psoriasis and Ulcerative colitis (UC). Despite the documented efficacy of IN in UC patients, concerns have been raised on the development of adverse effects with long term consumption, prompting a closer examination of its safety and tolerability in these contexts. This review aims to comprehensively assess the efficacy of IN in both clinical and pre-clinical settings, with a detailed exploration of the mechanisms of action involved. Additionally, it summarizes the observed potential toxicity of IN in animal and human settings was summarized. This review will deepen our understanding on the beneficial and detrimental effects of IN in UC, providing valuable insights for its future application in patients with this condition.

Curcumin-QingDai Combination for Patients With Active Ulcerative Colitis: A Randomized, Double-Blinded, Placebo-Controlled Trial

BACKGROUND & AIMS

We evaluated the efficacy of herbal combination of curcumin-QingDai (CurQD) in active ulcerative colitis (UC).

METHODS

Part I was an open-label trial of CurQD in patients with active UC, defined by a Simple Clinical Colitis Activity Index score of 5 or higher and a Mayo endoscopic subscore of 2 or higher. Part II was a placebo-controlled trial conducted in Israel and Greece, randomizing active UC patients at a 2:1 ratio to enteric-coated CurQD 3 g/d or placebo for 8 weeks. The co-primary outcome was clinical response (reduction in the Simple Clinical Colitis Activity Index of ≥3 points) and an objective response (Mayo endoscopic subscore improvement of ≥1 or a 50% fecal calprotectin reduction). Responding patients continued either maintenance curcumin or placebo alone for an additional 8 weeks. Aryl-hydrocarbon receptor activation was assessed by cytochrome P450 1A1 (CYP1A1) mucosal expression.

RESULTS

In part I, 7 of 10 patients responded and 3 of 10 achieved clinical remission. Of 42 patients in part II, the week 8 co-primary outcome was achieved in 43% and 8% of CurQD and placebo patients, respectively (P = .033). Clinical response was observed in 85.7% vs 30.7% (P < .001), clinical remission in 14 of 28 (50%) vs 1 of 13 (8%; P = .01), a 50% calprotectin reduction in 46.4% vs 15.4% (P = .08), and endoscopic improvement in 75% vs 20% (P = .036) in the CurQD and placebo groups, respectively. Adverse events were comparable between groups. By week 16, curcumin-maintained clinical response, clinical remission, and clinical biomarker response rates were 93%, 80%, and 40%, respectively. CurQD uniquely up-regulated mucosal CYP1A1 expression, which was not observed among patients receiving placebo, mesalamine, or biologics.

CONCLUSIONS

In this placebo-controlled trial, CurQD was effective for inducing response and remission in active UC patients. The aryl-hydrocarbon receptor pathway may merit further study as a potential UC treatment target.

CLINICALTRIALS

gov ID: NCT03720002.

Indigo naturalis (Qing dai) for inflammatory bowel disease: A systematic review and meta-analysis

BACKGROUND

Indigo naturalis (Qing dai) is a traditional therapy reported to be useful in inflammatory bowel disease (IBD), especially for ulcerative colitis. We performed a systematic review of its efficacy and safety in IBD.

METHODS

Electronic databases (Pubmed, Embase, and Scopus) were searched on 4th March 2023 to identify reports about the use of indigo naturalis in IBD. We extracted data with respect to clinical response, remission, endoscopic and histological responses, and adverse events with the use of indigo naturalis in IBD. Pooled clinical response rates and remission rates were calculated. The quality of studies was assessed using Joanna-Briggs tools.

RESULTS

Nine studies reporting on 299 patients were included. The pooled clinical response rate was 0.796 (95 %CI, 0.7465-0.8379, I2=0), and the clinical remission rate in ulcerative colitis was 0.668 (0.488- 0.809, I2=85.2 %). The pooled relative risk of clinical response was higher in the indigo naturalis group as compared to placebo in the two randomized trials [3.82 (2.04; 7.14, I2=0)]. Except for one reversible pulmonary arterial hypertension case, most reported adverse effects were mild. The endoscopic and histological responses, when reported, suggested that indigo naturalis is effective for ulcerative colitis. The limitations of the systematic review included a small number of randomized studies, reports only from East Asia and a relatively small number of patients, especially for Crohn's disease.

CONCLUSION

Indigo naturalis is effective in the treatment of ulcerative colitis. Future studies should evaluate the comparative efficacy with other drugs.

Ferroptosis in the colon epithelial cells as a therapeutic target for ulcerative colitis

BACKGROUND

Ferroptosis, a type of programmed cell death triggered by oxidative stress, was suspected to play a role in ulcerative colitis. Indigo naturalis is highly effective against ulcerative colitis, but its mechanism is unclear. This study found that indigo naturalis treatment suppressed ferroptosis.

METHODS

We analyzed 770 mRNA expressions of patients with ulcerative colitis. Suppression of ferroptosis by indigo naturalis treatment was shown using a cell death assay. Malondialdehyde levels and reactive oxygen species were analyzed in CaCo-2 cells treated with indigo naturalis. Glutathione metabolism was shown by metabolomic analysis. Extraction of the ingredients indigo naturalis from the rectal mucosa was performed using liquid chromatograph-mass spectrometry.

RESULTS

Gene expression profiling showed that indigo naturalis treatment increased antioxidant genes in the mucosa of patients with ulcerative colitis. In vitro analysis showed that nuclear factor erythroid-2-related factor 2-related antioxidant gene expression was upregulated by indigo naturalis. Indigo naturalis treatment rendered cells resistant to ferroptosis. Metabolomic analysis suggested that an increase in reduced glutathione by indigo naturalis. The protein expression of CYP1A1 and GPX4 was increased in the rectum by treatment with indigo naturalis. The main ingredients of indigo naturalis, indirubin and indigo inhibited ferroptosis. Indirubin was detected in the rectal mucosa of patients with ulcerative colitis who were treated with indigo naturalis.

CONCLUSIONS

Suppression of ferroptosis by indigo naturalis in the intestinal epithelium could be therapeutic target for ulcerative colitis. The main active ingredient of indigo naturalis may be indirubin.

Mechanism of Qingchang Suppository on repairing the intestinal mucosal barrier in ulcerative colitis

Ulcerative colitis (UC) is a refractory inflammatory bowel disease, and the outcomes of conventional therapies of UC, including 5-aminosalicylic acid, glucocorticoids, immunosuppressants, and biological agents, are not satisfied with patients and physicians with regard to adverse reactions and financial burden. The abnormality of the intestinal mucosal barrier in the pathogenesis of UC was verified. Qingchang Suppository (QCS) is an herbal preparation and is effective in treating ulcerative proctitis. The mechanism of QCS and its active ingredients have not been concluded especially in mucosal healing. This review elucidated the potential mechanism of QCS from the intestinal mucosal barrier perspective to help exploring future QCS research directions.

A primer on common supplements and dietary measures used by patients with inflammatory bowel disease

Inflammatory bowel disease (IBD) is a chronic disease of the intestines. The pathophysiology of IBD, namely Crohn's disease and ulcerative colitis, is a complex interplay between environmental, genetic, and immune factors. Physicians and patients often seek complementary and alternative medicines (CAMs) as primary and supplementary treatment modalities. CAMs in IBD span a wide range of plants, herbs, pre/probiotics, and include formulations, such as cannabis, curcumin, fish oil, and De Simone Formulation. Dietary measures are also used to improve symptoms by attempting to target trigger foods and reducing inflammation. Examples include the specific carbohydrate diet, the Mediterranean diet, and a diet low in fermentable oligo-, di- and monosaccharides as well as polyols (FODMAP). We examine and review the most common complementary supplements and diets used by patients with IBD.

Real-world experience with Curcumin-QingDai combination for patients with active ulcerative colitis: A retrospective multicentre cohort study

BACKGROUND

Curcumin and QingDai (QD, Indigo) have been shown to be effective for treating active ulcerative colitis (UC).

AIM

To evaluate the real-world experience with the Curcumin-QingDai (CurQD) herbal combination to induce remission in active UC.

METHODS

A retrospec-tive multicentre adult cohort study from five tertiary academic centres (2018-2022). Active UC was defined as a Simple Clinical Colitis Activity Index (SCCAI) ≥ 3. Patients were induced by CurQD. The primary outcome was clinical remission at weeks 8-12, defined as SCCAI ≤2 and a decrease ≥3 points from baseline. Secondary outcomes were clinical response (SCCAI decrease ≥3 points), corticosteroid-free remission, faecal calprotectin (FC) response (reduction ≥50%), FC normalisation (FC ≤100 μg/g for patients with FC ≥300 μg/g at baseline), and safety. All outcomes were analysed for patients who were maintaining stable treatment.

RESULTS

Eighty-eight patients were included; 50% were biologics/small molecules experienced, and 36.5% received ≥2 biologics/small molecules. Clinical remission was achieved in 41 (46.5%), and clinical response in 53 (60.2%). Median SCCAI decreased from 7 (IQR:5-9) to 2 (IQR:1-3); p < 0.0001. Of the 26 patients on corticosteroids at baseline, seven achieved corticosteroid-free remission. Among 43 biologics/small molecules experienced patients, clinical remission was achieved in 39.5% and clinical response in 58.1%. FC normalisation and response were achieved in 17/29 and 27/33, respectively. Median FC decreased from 1000 μg/g (IQR:392-2772) at baseline to 75 μg/g (IQR:12-136) at the end of inductions (n = 30 patients with paired samples); p < 0.0001. No overt safety signals emerged.

CONCLUSION

In this real-world cohort, CurQD effectively induced clinical and biomarker remission in patients with active UC, including patients who were biologics/small molecules experienced.

Activation of the aryl hydrocarbon receptor inhibits the development of experimental autoimmune pancreatitis through IL-22-mediated signaling pathways

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor expressed in hematopoietic and non-hematopoietic cells. Activation of the AhR by xenobiotics, microbial metabolites, and natural substances induces immunoregulatory responses. Autoimmune pancreatitis (AIP) is a chronic fibroinflammatory disorder of the pancreas driven by autoimmunity. Although AhR activation generally suppresses pathogenic autoimmune responses, the roles played by the AhR in AIP have been poorly defined. In this study, we examined how AhR activation affected the development of experimental AIP caused by the activation of plasmacytoid dendritic cells producing IFN-α and IL-33. Experimental AIP was induced in MRL/MpJ mice by repeated injections of polyinosinic-polycytidylic acid. Activation of the AhR by indole-3-pyruvic acid and indigo naturalis, which were supplemented in the diet, inhibited the development of experimental AIP, and these effects were independent of the activation of plasmacytoid dendritic cells producing IFN-α and IL-33. Interaction of indole-3-pyruvic acid and indigo naturalis with AhRs robustly augmented the production of IL-22 by pancreatic islet α cells. The blockade of IL-22 signaling pathways completely canceled the beneficial effects of AhR ligands on experimental AIP. Serum IL-22 concentrations were elevated in patients with type 1 AIP after the induction of remission with prednisolone. These data suggest that AhR activation suppresses chronic fibroinflammatory reactions that characterize AIP via IL-22 produced by pancreatic islet α cells.

Topical application of indigo-plant leaves extract enhances healing of skin lesion in an excision wound model in rats

OBJECTIVES

This study aims to evaluate the pharmacological role of indigo extract in accelerating the wound healing in a rat model.

METHODS

Female Sprague-Dawley rats were anesthetized with ketamine (30 mg/kg, i.p.) and the full thickness of the marked skin was then cut carefully and wounds were left undressed. Indigo extract (5%) in PBS was applied topically twice daily until healing was complete. A control group of rats was treated with povidone-iodide (Betadine®). Rats treated with phosphate buffer saline were used as a negative control group. The rate of wound healing was assessed daily. Histopathological examination of skin sections were qualitatively assessed by independent evaluators. The inflammatory and apoptotic markers were assessed in skin tissue homogenates using ELISA.

RESULTS

Histopathology data showed that applying indigo to skin wounds enhanced the healing process, resulting in a significant decrease in dermal inflammation in comparison to untreated rats. Topical application of indigo significantly increased antioxidant enzyme activities with reduced malondialdehyde (MDA) levels in wound tissues. The levels of matrix metalloproteases-2 and -9 were significantly lower with an accompanied increase in the level of TGF-β1 in skin tissues from rats treated with indigo compared to the control group treated with PBS.

CONCLUSIONS

The antioxidant and anti-inflammatory properties of indigo leaf extract accelerate the healing of skin injuries.

Network Pharmacology and Molecular Docking Analysis on Molecular Mechanism of Qingzi Zhitong Decoction in the Treatment of Ulcerative Colitis

Ulcerative colitis (UC) is a disease with complex pathological mechanisms. We explored the potential molecular mechanisms behind the therapeutic functions of Qingzi Zhitong decoction (QZZTD) in the treatment of UC by network pharmacology and molecular docking. QZZTD is a formula of Chinese traditional medicine consisting of 10 herbs. The potential active ingredients of QZZTD and their target genes were obtained from the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform database, and UC-related target genes were obtained from GeneCards and OMIM databases. A total of 138 co-identified target genes were obtained by plotting the intersection target Venn diagram, and then the STRING database and Cytoscape software were used to establish protein-protein interaction networks and herb-ingredient-target networks. Four key active compounds and nine key proteins were identified. Then, Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses showed that the biological functions of potential target genes were associated with DNA transcription, signaling receptor and ligand activity, cytokine activity, cellular autophagy, and antioxidant pathways, with related pathways involving the phosphatidylinositol 3-kinase (PI3K)-Akt signaling pathway, advanced glycosylation end product (AGE)-RAGE signaling pathway, tumor necrosis factor (TNF) signaling pathway, and IL-17 signaling pathway. Moreover, the binding activities of key target genes and essential active compounds of Chinese herbal medicines in QZZTD were further validated by molecular docking. This demonstrated that quercetin, luteolin, hyndarin, and beta-sitosterol had good binding to eight key proteins, and Akt1 was the target protein with the best binding activity, suggesting that Akt1 could be the essential mediator responsible for signaling transduction after QZZTD administration. The rat experiment verified that QZZTD inhibited PI3K-Akt pathway activation and reduced inflammation in UC. In conclusion, our study suggested four potential key active components, including quercetin, were identified in QZZTD, which could interact with Akt1 and modulate the activation of the PI3K-Akt pathway. The other three pathways may also be involved in the signaling transduction induced by QZZTD in the treatment of UC.

Ban-Lan-Gen Granule Alleviates Dextran Sulfate Sodium-Induced Chronic Relapsing Colitis in Mice via Regulating Gut Microbiota and Restoring Gut SCFA Derived-GLP-1 Production

PURPOSE

GLP-1 based therapy represents a new treatment option for inflammatory bowel disease. Ban-Lan-Gen (BLG) granule, a known anti-viral TCM formulation, exhibits potential anti-inflammatory activities in treating various kinds of inflammation. However, its anti-inflammatory effect on colitis and the underlying mechanisms remain unknown.

METHODS

Dextran sulfate sodium (DSS)-induced chronic relapsing colitis in mice was established. The disease activity index, histological sign of damage, and levels of proinflammatory cytokines were performed to assess the protective effects of BLG. Serum GLP-1 level and colonic Gcg, GPR41 and GRP43 expression, the community compositions of gut microbiota, the levels of SCFAs in the feces and GLP-1 release from primary murine colon epithelial cells were performed to characterize the effects of BLG on gut microbiota and gut SCFA derived-GLP-1 production.

RESULTS

BLG treatment significantly alleviated body weight loss, DAI, colon shortening, colon tissue damage, and pro-inflammatory cytokine levels of TNF-α, IL-1β and IL-6 in the colon tissues. Moreover, BLG treatment could observably restore colonic Gcg, GPR41 and GRP43 expression and serum GLP-1 level of colitic mice, as well as correct the alteration of gut microbiota in colitic mice by increasing the abundances of SCFA-producing bacteria, eg, Akkermansia and Prevotellaceae_UCG-001, and decreasing the abundances of bacteria, eg, Eubacterium_xylanophilum_group, Ruminococcaceae_UCG-014, Intestinimonas, and Oscillibacter. Furthermore, BLG treatment could markedly increase the levels of SCFAs in feces of colitic mice. In parallel, ex vivo assay also showed that and the extract of feces from BLG-treatment mice could greatly stimulate the secretion of GLP-1 from primary murine colon epithelial cells.

CONCLUSION

These findings suggest that the anti-colitis effects of BLG are achieved at least partly by regulating gut microbiota and restoring gut SCFA derived-GLP-1 production, and BLG has the potential to be developed as a promising agent for the treatment of chronic relapsing colitis.

Qing-Dai for pediatric ulcerative colitis multicenter survey and systematic review

BACKGROUND

Pediatric ulcerative colitis (UC) is more challenging to treat than adult UC. Qing-Dai therapy is effective in adults but reports of its efficacy in children are unavailable. We conducted a questionnaire survey on Qing-Dai use among pediatric patients with UC in Japan to determine its efficacy and safety.

METHODS

Questionnaires were sent to 31 high-volume centers treating pediatric patients with inflammatory bowel disease. The number of patients using Qing-Dai, short-term and long-term effects, and adverse events were assessed. A systematic review of studies on the efficacy and safety of Qing-Dai usage for UC was also performed.

RESULTS

Overall, 29/31 facilities (93.5%) responded, Qing-Dai was used in 107 patients with UC, and 84/107 patients (78.5%) initiated treatment. Within 6 months, 81/101 (80.2%) patients had clinical remission, while 59/92 (64.1%) patients had no relapse and 29/92 (31.5%) experienced only one to two relapses yearly. Eighty-seven percent of the patients underwent regular follow ups for adverse events, among whom one patient was diagnosed with pulmonary arterial hypertension (PAH), five with enteritis, and one with headache. In the systematic review, the clinical remission rate was 50-80%, and PAH was observed in 14 of 1,158 patients (1.2%).

CONCLUSIONS

Qing-Dai is highly effective in treating pediatric UC. However, Qing-Dai should be administered with caution as it may cause adverse events such as PAH.

Treatment-refractory ulcerative colitis responsive to indigo naturalis

Background

Indigo naturalis (IN) is an herbal medicine that has been used for ulcerative colitis with an unclear mechanism of action. Indigo and indirubin, its main constituents, are ligands of the aryl hydrocarbon receptor (AhR). We assessed the safety, efficacy, and colon AhR activity of IN given orally to patients with treatment-refractory ulcerative colitis. The role of AhR in IN benefit was further evaluated with an AhR antagonist in a murine colitis model.

Methods

This open-label, dose-escalation study sequentially treated 11 patients with ulcerative colitis with either IN 500 mg/day or 1.5 g/day for 8 weeks, followed by a 4-week non-treatment period. The primary efficacy endpoint was clinical response at week 8, assessed by total Mayo score. Secondary endpoints included clinical remission, Ulcerative Colitis Endoscopic Index of Severity, quality of life, and colon AhR activity measured by cytochrome P450 1A1 (CYP1A1) RNA expression.

Results

Ten of 11 (91%) patients, including 8/9 (89%) with moderate-to-severe disease, achieved a clinical response. Among these 10 patients, all had failed treatment with 5-aminosalicylic acid, 8 patients with a tumour necrosis factor (TNF)-alpha inhibitor, and 6 patients with TNF-alpha inhibitor and vedolizumab. Five patients were corticosteroid dependent. Clinical response was observed in all five patients who had been recommended for colectomy. Three patients achieved clinical remission. All patients experienced improved endoscopic severity and quality of life. Four weeks after treatment completion, six patients had worsened partial Mayo scores. Four patients progressed to colectomy after study completion. Colon CYP1A1 RNA expression increased 12 557-fold at week 8 among six patients evaluated. No patient discontinued IN due to an adverse event. Concomitant administration of 3-methoxy-4-nitroflavone, an AhR antagonist, in a murine colitis model abrogated the benefit of IN.

Conclusion

IN is a potentially effective therapy for patients with treatment-refractory ulcerative colitis. This benefit is likely through AhR activation.

Trial registration number

NCT02442960.

Copper-Catalyzed Oxidative C(sp3)-H/C(sp3)-H Cross-Coupling Reaction of 3-Methylbenzo[c]isoxazoles with Methyl Ketones: Access to Indigoid Analogues

A copper-catalyzed oxidative C(sp³)-H/C(sp³)-H cross-coupling reaction of methyl ketones and 3-methylbenzo[c]isoxazoles has been developed for the direct synthesis of 3-oxoindolin-2-ylidene derivatives. This process involves an intermolecular nucleophilic addition/ring-opening/aza-Michael addition cascade, providing indigoid analogues with high atom economy and as single isomers exclusively under mild conditions.

Immunomodulatory drug discovery from herbal medicines: Insights from organ-specific activity and xenobiotic defenses

Traditional herbal medicines, which emphasize a holistic, patient-centric view of disease treatment, provide an exciting starting point for discovery of new immunomodulatory drugs. Progress on identification of herbal molecules with proven single agent activity has been slow, in part because of insufficient consideration of pharmacology fundamentals. Many molecules derived from medicinal plants exhibit low oral bioavailability and rapid clearance, leading to low systemic exposure. Recent research suggests that such molecules can act locally in the gut or liver to activate xenobiotic defense pathways that trigger beneficial systemic effects on the immune system. We discuss this hypothesis in the context of four plant-derived molecules with immunomodulatory activity: indigo, polysaccharides, colchicine, and ginsenosides. We end by proposing research strategies for identification of novel immunomodulatory drugs from herbal medicine sources that are informed by the possibility of local action in the gut or liver, leading to generation of systemic immune mediators.

Role of AHR Ligands in Skin Homeostasis and Cutaneous Inflammation

Aryl hydrocarbon receptor (AHR) is an important regulator of skin barrier function. It also controls immune-mediated skin responses. The AHR modulates various physiological functions by acting as a sensor that mediates environment–cell interactions, particularly during immune and inflammatory responses. Diverse experimental systems have been used to assess the AHR’s role in skin inflammation, including in vitro assays of keratinocyte stimulation and murine models of psoriasis and atopic dermatitis. Similar approaches have addressed the role of AHR ligands, e.g., TCDD, FICZ, and microbiota-derived metabolites, in skin homeostasis and pathology. Tapinarof is a novel AHR-modulating agent that inhibits skin inflammation and enhances skin barrier function. The topical application of tapinarof is being evaluated in clinical trials to treat psoriasis and atopic dermatitis. In the present review, we summarize the effects of natural and synthetic AHR ligands in keratinocytes and inflammatory cells, and their relevance in normal skin homeostasis and cutaneous inflammatory diseases.

Exploring the Mechanism of Indigo Naturalis in the Treatment of Ulcerative Colitis Based on TLR4/MyD88/NF-κB Signaling Pathway and Gut Microbiota

Background: Clinical trials have proven that indigo naturalis is a candidate drug for treating ulcerative colitis (UC), but its therapeutic mechanism is still unclear.

Purpose: This study aimed to evaluate the protective effect and mechanism of indigo naturalis to treat mice with dextran sulfate sodium (DSS)-induced UC.

Methods: DSS-induced UC mice were treated with indigo naturalis (200 mg/kg), indigo (4.76 mg/kg), and indirubin (0.78 mg/kg) for 1 week. The anti-UC mechanism of indigo naturalis was studied by pathological section, inflammatory factor, western blot, and 16S rRNA sequencing.

Results: According to body weight change, disease activity index, and colon length, indigo naturalis had the strongest anti DSS-induced UC effect, followed by indirubin and indigo. Pathological section showed that indigo naturalis, indigo, and indirubin could reduce the infiltration of inflammatory cells, increase the secretion of intestinal mucus, and repair the intestinal mucosa. Indigo naturalis, indigo, and indirubin could reduce IL-1β,IL-6, and TNF-α by inhibiting TLR4/MyD88/NF-κB signal transduction. Indigo naturalis and indigo could also reduce IgA and IgG both in serum and colon tissue. In addition, indigo naturalis, indigo, and indirubin could adjust the gut microbiota structure of DSS-induced UC mice, reducing the ratio of Firmicutes/Bacteroidetes and increasing the abundance of probiotics.

Conclusion: Indigo and indirubin are one of the main anti-UC components of indigo naturalis. INN could regulate intestinal flora, reduce inflammation, repair intestinal mucosa, and improve the physiological status of DSS-induced UC mice and its anti-UC mechanism may be involved in inhibiting TLR4/MyD88/NF-κB signal transduction.

A Comprehensive Review of the Chemistry, Pharmacokinetics, Pharmacology, Clinical Applications, Adverse Events, and Quality Control of Indigo Naturalis

Indigo naturalis (IN), which is derived from indigo plants such as Strobilanthes cusia (Nees) Kuntze, Persicaria tinctoria (Aiton) Spach, and Isatis tinctoria L., has been traditionally used in the treatment of hemoptysis, epistaxis, chest pain, aphtha, and infantile convulsion in China for thousands of years. Clinical trials have shown that the curative effect of IN for psoriasis and ulcerative colitis (UC) is remarkable. A total of sixty-three compounds, including indole alkaloids, terpenoids, organic acids, steroids, and nucleosides, have been isolated from IN, of which indole alkaloids are the most important. Indirubin, isolated from IN, was used as a new agent to treat leukemia in China in the 1970s. Indirubin is also an active ingredient in the treatment of psoriasis. Pharmacological studies have confirmed that IN has inhibitory effects on inflammation, tumors, bacteria, and psoriasis. Indigo, indirubin, tryptanthrin, isorhamnetin, indigodole A, and indigodole C are responsible for these activities. This review provides up-to-date and comprehensive information on IN with regard to its chemistry, pharmacokinetics, pharmacology, clinical applications, adverse events, and quality control. This review may also serve a reference for further research on IN.

Anti-inflammation effect of Qingchang suppository in ulcerative colitis through JAK2/STAT3 signaling pathway in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Qingchang Suppository (QCS) is a Traditional Chinese Medicine formula (TCM) for Ulcerative Colitis (UC), which has been used for the treatment of UC for more than 30 years with therapeutic effect. This formula is optimized from a classic formula called "Qingdai San". Although some experiments have shown QCS effective for UC, its mechanism on UC is still unclear and needs to be clarified.

AIM OF THE STUDY

To investigate the usage of QCS in our hospital, clarify the main compounds in QCS and their anti-inflammation effect both in vivo and in vitro.

MATERIALS AND METHODS

Prescription analysis was performed in the clinical department and pharmacology network prediction was predicted for relative signal pathways. 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced colitis rats and Lipopolysaccharide (LPS)-induced Caco-2 cell as an inflammatory model were used to evaluate the effect of QCS.

RESULTS

QCS and its herbs were associated with inflammatory and immunological diseases. QCS and its ingredients showed little toxicity on Caco-2 cell and could down-regulate the level of Interleukin-6 (IL-6) and expression of signal transducer and activator of transcription 3 (P-STAT3 Tyr705) in LPS-induced Caco-2 cell. In an animal experiment, QCS and its ingredients (indigo and gallic acid) could alleviate the symptoms of TNBS-induced colitis of rats, significantly decrease pro-inflammatory factors and anti-inflammatory factors as well as inhibit the expressions of P-STAT3 and Tyr705.

CONCLUSION

QCS and its components could improve UC by anti-inflammation. JAK2/STAT3 pathway might be the possible signaling pathway.

Indigo Naturalis Ameliorates Dextran Sulfate Sodium-Induced Colitis in Mice by Modulating the Intestinal Microbiota Community

Indigo naturalis (IN) is a traditional Chinese medicine, named Qing-Dai, which is extracted from indigo plants and has been used to treat patients with inflammatory bowel disease (IBD) in China and Japan. Though there are notable effects of IN on colitis, the mechanisms remain elusive. Regarding the significance of alterations of intestinal flora related to IBD and the poor water solubility of the blue IN powder, we predicted that the protective action of IN on colitis may occur through modifying gut microbiota. To investigate the relationships of IN, colitis, and gut microbiomes, a dextran sulfate sodium (DSS)-induced mice colitis model was tested to explore the protective effects of IN on macroscopic colitis symptoms, the histopathological structure, inflammation cytokines, and gut microbiota, and their potential functions. Sulfasalazine (SASP) was used as the positive control. Firstly, because it was a mixture, the main chemical compositions of indigo and indirubin in IN were detected by ultra-performance liquid chromatography (UPLC). The clinical activity score (CAS), hematoxylin and eosin (H&E) staining results, and enzyme-linked immunosorbent assay (ELISA) results in this study showed that IN greatly improved the health conditions of the tested colitis mice, ameliorated the histopathological structure of the colon tissue, down-regulated pro-inflammatory cytokines, and up-regulated anti-inflammatory cytokines. The results of 16S rDNA sequences analysis with the Illumina MiSeq platform showed that IN could modulate the balance of gut microbiota, especially by down-regulating the relative quantity of Turicibacter and up-regulating the relative quantity of Peptococcus. The therapeutic effect of IN may be closely related to the anaerobic gram-positive bacteria of Turicibacter and Peptococcus. The inferred metagenomes from 16S data using PICRUSt demonstrated that decreased metabolic genes, such as through biosynthesis of siderophore group nonribosomal peptides, non-homologous end-joining, and glycosphingolipid biosynthesis of lacto and neolacto series, may maintain microbiota homeostasis during inflammation from IN treatment in DSS-induced colitis.