Anti-angiogenesis in colorectal cancer therapy.

The morbidity of colorectal cancer (CRC) has risen to third place among malignant tumors worldwide. In addition, CRC is a common cancer in China whose incidence increases annually. Angiogenesis plays an important role in the development of tumors because it can bring the nutrients that cancer cells need and take away metabolic waste. Various mechanisms are involved in the formation of neovascularization, and vascular endothelial growth factor is a key mediator. Meanwhile, angiogenesis inhibitors and drug resistance (DR) are challenges to consider when formulating treatment strategies for patients with different conditions. Thus, this review will discuss the molecules, signaling pathways, microenvironment, treatment, and DR of angiogenesis in CRC.

Differentiating Gastrointestinal Stromal Tumors From Leiomyomas of Upper Digestive Tract Using Convolutional Neural Network Model by Endoscopic Ultrasonography.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) and leiomyomas are the most common submucosal tumors of the upper digestive tract, and the diagnosis of the tumors is essential for their treatment and prognosis. However, the ability of endoscopic ultrasonography (EUS) which could correctly identify the tumor types is limited and closely related to the knowledge, operational level, and experience of the endoscopists. Therefore, the convolutional neural network (CNN) is used to assist endoscopists in determining GISTs or leiomyomas with EUS. MATERIALS AND METHODS: A model based on CNN was constructed according to GoogLeNet architecture to distinguish GISTs or leiomyomas. All EUS images collected from this study were randomly sampled and divided into training set (n=411) and testing set (n=103) in a ratio of 4:1. The CNN model was trained by EUS images from the training set, and the testing set was utilized to evaluate the performance of the CNN model. In addition, there were some comparisons between endoscopists and CNN models. RESULTS: It was shown that the sensitivity and specificity in identifying leiomyoma were 95.92%, 94.44%, sensitivity and specificity in identifying GIST were 94.44%, 95.92%, and accuracy in total was 95.15% of the CNN model. It indicates that the diagnostic accuracy of the CNN model is equivalent to skilled endoscopists, or even higher than them. CONCLUSION: While identifying GIST or leiomyoma, the performance of CNN model was robust, which is highlighting its promising role in supporting less-experienced endoscopists and reducing interobserver agreement.

Efficacy of endoscopic ultrasound and endoscopic resection for esophageal schwannoma.

BACKGROUND: Esophageal schwannoma (ES) is a rare submucosal tumor, and its complete and safe resection is a topic that deserves special attention. AIM: This study aimed to investigate the clinical value of endoscopic ultrasound (EUS) in the diagnosis of ES and the clinical efficacy of endoscopic resection for ES. METHODS: The clinical data, endoscopic characteristics, endoscopic treatment, postoperative complications, immunohistochemical results, and follow-up records of patients with ES admitted to the Tianjin Medical University General Hospital from January 2012 to January 2022 were retrospectively analyzed. RESULTS: Under white-light endoscopy, 81.8% (9/11) of lesions were submucosal elevations, covering the normal esophageal epithelium. Two of the lesions with redness and erosive surface. Eight lesions (72.7%) appear on EUS originating from the muscularis propria were homogeneous or inhomogeneous hypoechoic signals. Two lesions were inhomogeneous hyperechoic originating from the submucosa or muscularis propria, respectively. One lesion was homogeneous hypoechoic originating from the submucosa. All lesions had no blood flow signals, cystic changes, or calcification, and were completely removed by submucosal tunnel endoscopic resection (STER) or endoscopic submucosal dissection (ESD). All patients did not experience serious adverse events as well as recurrence, metastasis, or cicatricial esophageal stenosis during the follow-up period. CONCLUSION: ES is a rare submucosal lesion, which endoscopic characteristics are difficult to distinguish from other esophageal submucosal tumors. Endoscopic resection can provide a minimally invasive and alternative treatment for ES.

Prognostic value and immunological roles of GPX3 in gastric cancer.

Objective: The prognosis for gastric cancer (GC), a prevalent tumor of the digestive system, is unfavorable. The involvement of glutathione peroxidase 3 (GPX3) in tumorigenesis is significant, yet its specific role in GC remains insufficiently investigated. Thus, the aim of this study was to determine the potential impact of GPX3 on GC and elucidate the underlying mechanism. Methods: The expression and survival of GPX3 in GC were analyzed using TCGA data. Additionally, the GPX3 mRNA and protein levels in GC were also assessed using datasets from GTEx, GEPIA, and HPA. A total of 38 pairs of GC tissues, along with their adjacent normal tissues, were collected from the Tianjin Medical University General Hospital, accompanied by detailed clinical information. The expression levels of GPX3 were subsequently determined for the purpose of validation. Following expression, correlation, and survival analyses, we proceeded to investigate the upstream non-coding RNA (ncRNA) of GPX3 using starBase and miRNet. Additionally, the co-expression networks of GPX3 were examined based on LinkedOmics. Lastly, we explored the correlation between GPX3 and immune cell infiltration, as well as the biomarkers of immune cells and immune checkpoints in GC. Furthermore, the GDSC database offered valuable drug sensitivity information. Results: A lower expression of GPX3 was observed in individuals with GC, while a higher expression of GPX3 was associated with a poorer prognosis. The DUBR/hsa-miR-502-3p/GPX3 pathway was identified as the most promising upstream ncRNA pathway related to GPX3 in GC. GO and KEGG enrichment analysis revealed that GPX3 expression was linked to coagulation cascades and cell locomotion. Furthermore, GPX3 levels in GC were positively correlated with immune cell infiltration, immune cell biomarkers, and immune checkpoint expression. The group with low GPX3 expression also exhibited increased sensitivity to 5-fluorouracil, doxorubicin, and other drugs. Conclusions: Collectively, we hypothesized that the potential involvement of non-coding RNAs in the downregulation of GPX3 could contribute to the inhibition of tumor formation during the malignant transition from gastritis to GC. Nevertheless, it was plausible that GPX3 may also facilitate tumor progression to advanced stages by promoting immune cell infiltration and activating immune checkpoints.

Design, Synthesis and Biological Evaluation of Conjugates of 3-O-Descladinose-azithromycin and Nucleobases against rRNA A2058G- or A2059G-Mutated Strains.

Structurally unrelated antibiotics MLSB (macrolide-lincosamide-streptogramin B) compromised with clinically resistant pathogens because of the cross-resistance resulting from the structural modification of rRNA A2058. The structure-activity relationships of a novel 3-O-descladinose azithromycin chemotype conjugating with nucleobases were fully explored with the aid of engineered E. coli SQ110DTC and SQ110LPTD. The conjugates of macrolides with nucleobases, especially adenine, displayed antibacterial superiority over telithromycin, azithromycin and clindamycin against rRNA A2058/2059-mutated engineered E. coli strains at the cost of lowering permeability and increasing vulnerability to efflux proteins against clinical isolates.

Therapeutic potential of Saccharomyces boulardii in liver diseases: from passive bystander to protective performer?

Saccharomyces boulardii (S. boulardii) is a probiotic yeast that has been elucidated to be efficacious in fighting various gastrointestinal diseases in preclinical as well as clinical studies. Its general mechanisms of probiotic action in the treatment of gastrointestinal conditions cover multifaceted aspects, including immune regulation, production of antimicrobial substances, pathogen competitive elimination, gut barrier integrity maintenance, intestinal trophic effect and antioxidant potency. In this review, basic knowledge with regard to the gut-liver axis, available probiotics remedies and mechanistic insights of S. boulardii as probiotics will be elucidated. In addition, we summarize the therapeutic potential of S. boulardii in several liver diseases evident from both bench and bedside information, such as acute liver injury/failure, fibrosis, hepatic damages due to metabolic disturbance or infection and obstructive jaundice. Future prospects in relation to medicinal effects of S. boulardii are also exploited and discussed on the basis of novel and attractive therapeutic concept in the latest scientific literature.

Role of endoscopic ultrasound and endoscopic resection in the diagnosis and treatment of esophageal granular cell tumors.

BACKGROUND AND AIM: Diagnosis and complete resection of esophageal granular cell tumors (GCTs) is an area of concern. However, articles on endoscopic ultrasound (EUS) and endoscopic resection of esophageal granular cell tumors are few. To evaluate the role of endoscopic ultrasound and endoscopic resection in the diagnosis and treatment of esophageal granular cell tumors. METHODS: A retrospective analysis of 15 patients with esophageal granular cell tumors who underwent endoscopic ultrasound examination and endoscopic resection in our hospital was conducted. The clinical data, endoscopic ultrasound images, endoscopic treatment, pathological characteristics, postoperative complications and follow-up status of all patients were evaluated. Ten board-certified endoscopists independently evaluated the white light endoscopic images of the 15 patients (Test 1) and the endoscopic ultrasound images together with white light endoscopic images of the same patient set (Test 2). RESULT: Female patients accounted for 53.4% of the participants. The average age at the time of diagnosis was 49.13 ± 9.31 years old. Ten lesions (66.67%) showed hypoechoic signal, four lesions (26.67%) showed hyperechoic signal and one lesion showed medium signal. The diagnostic accuracy was significantly higher with Test 2(65.3% vs. 92.0%, p < .001). Complete endoscopic resection was performed in all the patients. No complications occurred in any of the patients. No esophageal stenosis, recurrence, or metastases was found in all patients during the follow-up period. CONCLUSION: The endoscopic ultrasound images of esophageal granular cell tumors have certain characteristics that help diagnose esophageal granular cell tumors. Endoscopic resection of esophageal granular cell tumors is an effective, safe and feasible treatment method.

The Efficacy of Proton Pump Inhibitor in Cirrhotics with Variceal Bleeding: A Systemic Review and Meta-Analysis.

BACKGROUND AND AIMS: Proton pump inhibitor (PPI) was widely used in cirrhotic patients with variceal bleeding empirically rather than evidence-based practice. We aimed to evaluate the plausible indication of PPI use in variceal bleeding cirrhotic patients and figure out whether it can decrease the re-bleeding rate after endoscopic therapy. Furthermore, we also investigated the association between PPI and bleeding-related mortality in these patients. METHODS: We have searched in PubMed, Medline, Web of Science, Google Scholar, Cochrane and Embase prior to May 2019. Pooled OR and 95% CI were calculated by random-effects model. RESULTS: A total of 11 original articles including 1,818 cirrhotic patients were analyzed. The overall meta-analysis highlighted that PPI use may decrease the re-bleeding rate after endoscopic therapy (OR 0.52, 95% CI 0.35-0.77). The conclusion was irrespective of study methods, endoscopic purpose and hemorrhage sites. However, the conclusion speculated that PPI should be prescribed >1 month. Meanwhile, PPI use may not impact the bleeding-related mortality. CONCLUSIONS: PPI, used for >1 month, can decrease re-bleeding rate after endoscopic therapy in cirrhotic patients for prophylaxis or emergency treatment purpose. No matter how long it takes, PPI use is not associated with bleeding-related mortality.

Profiling changes in microRNAs of immature dendritic cells differentiated from human monocytes.

MicroRNAs (miRNAs) critically impact a wide array of eukaryotic developmental and physiologic processes through post-transcriptional gene silencing. In this study, we employed miRNA array and investigated in vitro the miRNA profile of immature dendritic cells (iDCs) derived from monocytes isolated from human venous blood. Our results showed that there were 379 miRNAs which were detectable in both monocytes and iDCs among the 856 miRNAs assayed, of which 155 miRNAs were detectable in monocytes while 224 miRNAs were detectable in iDCs. There were 103 miRNAs differentially expressed which could be relevant to the differentiation of iDCs from human monocytes. Sixty-two out of 103 miRNAs were upregulated whereas 41 miRNAs were downregulated. Of particular interest were the tremendous upregulation of miR122a and the downregulation of miR200c in iDCs. In addition, it was found that the strikingly downregulated miRNAs in iDCs also included miR-335, miR-514, miR-509, miR-31, miR-442b, miR-1, miR-199a, miR-203, miR-363 and miR-489 whereas the upregulation of miR-210, miR-155, miR-126, miR-139, miR-452, miR-19a, miR-25 and miR-181d were remarkable. Our results revealed a profile change of miRNAs when human iDCs were differentiated from monocytes as a result of in vitro stimulation with relevant cytokines.

The gut microbiota at the intersection of bile acids and intestinal carcinogenesis: An old story, yet mesmerizing.

The prevalence of colorectal cancer (CRC) has markedly increased worldwide in the last decade. Alterations of bile acid metabolism and gut microbiota have been reported to play vital roles in intestinal carcinogenesis. About trillions of bacteria have inhabited in the human gut and maintained the balance of host metabolism. Bile acids are one of numerous metabolites that are synthesized in the liver and further metabolized by the gut microbiota, and are essential in maintaining the normal gut microbiota and lipid digestion. Multiple receptors such as FXR, GPBAR1, PXR, CAR and VDR act as sensors of bile acids have been reported. In this review, we mainly discussed interplay between bile acid metabolism and gut microbiota in intestinal carcinogenesis. We then summarized the critical role of bile acids receptors involving in CRC, and also addressed the rationale of multiple interventions for CRC management by regulating bile acids-microbiota axis such as probiotics, metformin, ursodeoxycholic acid and fecal microbiota transplantation. Thus, by targeting the bile acids-microbiota axis may provide novel therapeutic modalities in CRC prevention and treatment.

Immunoglobulin G4-Related Disease Manifesting as Isolated, Typical, and Nontypical Gastroesophageal Lesion: A Research of Literature Review.

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is an autoimmune inflammatory and fibrotic condition. The disease is characterized by tissue infiltration with dense lymphoplasmacytes and IgG4-positive plasma cells. SUMMARY: The aim of this study was to provide gastroenterologists with novel insights into evaluating the gastroesophageal involvement with IgG4-RD or mimickers of this condition and to give special attention to clinicopathological features. A literature review was performed using the PubMed database. A total of 39 studies presenting cases in the form of isolated, typical, and nontypical gastroesophageal involvement with IgG4-RD published between 2010 and 2018 were included. These studies were thoroughly reviewed for symptoms, lesion location, lesion type, lesion size, immune-histopathology, associated diseases, treatment, and follow-up. Of the 39 studies reviewed, 9 were esophageal IgG4-RD lesions, isolated esophageal IgG4-RD 66.66% (6/9), a typical form of esophageal IgG4-RD 11.11% (1/9), and nontypical form esophageal IgG4-RD 22.22% (2/9). The 30 gastric IgG4-RD that include isolated gastric IgG4-RD 46.66% (14/30), typical gastric IgG4-RD 40% (12/30), and nontypical gastric IgG4-RD 13.33% (4/30). The majority of lesions were inflammatory tumors, ulceration, nodular lesions, chronic gastritis, and malignant lesions. Key Messages: IgG4-RD may be manifested by isolated, typical and nontypical forms of gastroesophageal lesions and should be taken into consideration in the differential diagnosis. Corticosteroids may be the sole diagnostic treatment for this condition.

Endoscopic Ultrasound Imaging for Differential Diagnosis of Pancreatic Neoplasms: A 7-Year Study in a Chinese Population.

BACKGROUND Currently, non-invasive methods for screening pancreatic cancer are lacking. There is little information regarding whether endoscopic ultrasound (EUS) imaging has a discriminatory ability for detecting benign and malignant pancreatic neoplasms. In this study, we retrospectively analyzed the demographic, clinicopathologic, and EUS features and follow-up information. MATERIAL AND METHODS A total of 58 patients with pancreatic neoplasms who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) over a 7-year period (2009-2016) at our Department of Digestive Diseases were enrolled in our study. RESULTS Of the 58 patients, 38 (65.5%) were diagnosed with malignant pancreatic neoplasms and 20 (34.5%) were benign ones. Of all the EUS findings, size of neoplasm (P=0.037) and regularity of margin (P=0.011) were significantly different between malignant and benign pancreatic neoplasms. However, age, sex, location, echo pattern, and dilation of main pancreatic duct did not show any significant difference (P>0.05). Size combined with regularity to detect malignant pancreatic neoplasms showed the following diagnostic values: sensitivity, 73.68%; specificity, 90%; positive predictive value, 76.60%; negative predictive value 81.82%; and area under the receiver operating characteristic curve, 0.887 (95% CI: 0.777-0.955, P<0.0001). CONCLUSIONS Our results showed the high value of EUS for differentiating malignant pancreatic neoplasms from benign ones. Due to this and its non-invasive nature, EUS should be the first-line method for detection of neoplastic pancreatic lesions.

A review of the relationship between the gut microbiota and amino acid metabolism.

New evidence has emerged in recent years to suggest a strong link between the human gut microbiota, its metabolites, and various physiological aspects of hosts along with important pathophysiological dimensions of diseases. The research indicates that the gut microbiota can facilitate metabolite production in two ways: first, the resident species of the gut microbiota use the amino acids produced from food or the host as elements for protein synthesis, and second, conversion or fermentation are used to drive nutrient metabolism. Additionally, the gut microbiota can synthesize several nutritionally essential amino acids de novo, which is a potential regulatory factor in amino acid homeostasis. The primary objective of this review is to summarize the current literature relating to the ways in which microbial amino acids contribute to host amino acid homeostasis.

Brachytherapy Using Elastin-Like Polypeptides with (131)I Inhibit Tumor Growth in Rabbits with VX2 Liver Tumor.

BACKGROUND: Brachytherapy is a targeted type of radiotherapy utilized in the treatment of cancers. Elastin-like polypeptides are a unique class of genetically engineered peptide polymers that have several attractive properties for brachytherapy. AIMS: To explore the feasibility and application of brachytherapy for VX2 liver tumor using elastin-like polypeptides with (131)I so as to provide reliable experimental evidence for a new promising treatment of liver cancer. METHODS: Elastin-like polypeptide as carrier was labeled with (131)I using the iodogen method. Ten eligible rabbits with VX2 liver tumor were randomly divided into the treatment group (n = 5) and control group (n = 5). The treatment group received brachytherapy using elastin-like polypeptide with (131)I, and in the control group, elastin-like polypeptide was injected into the VX2 liver tumor as a control. Periodic biochemical and imaging surveillances were required to assess treatment efficacy. RESULTS: The stability of elastin-like polypeptide with (131)I in vitro was maintained at over 96.8 % for 96 h. Biochemistry and imaging indicated brachytherapy using elastin-like polypeptide with (131)I for liver tumor can improve liver function and inhibit tumor growth (P < 0.05). CONCLUSIONS: Elastin-like polypeptide can be an ideal carrier of (131)I and have high labeling efficiency, radiochemical purity and stability. Brachytherapy using elastin-like polypeptide with (131)I for liver tumor is a useful therapy that possesses high antitumor efficacy advantages.

A feasibility study of a thermally sensitive elastin-like polypeptide for submucosal injection application in endoscopic resection in 3 animal models.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) can successfully resect large lesions en bloc by using a submucosal injection solution, but the cost of currently available submucosal injection solutions is not satisfactory. The authors' aim was to evaluate the feasibility and effectiveness of a thermally sensitive elastin-like polypeptide (ELP) used as submucosal injection solution in ESD. METHODS: We conducted an ex vivo study to determine the optimal concentration of ELPs in rabbits, an in vivo study to evaluate the effectiveness of mucosal elevation in rats, and a large animal study to confirm the feasibility of preclinical application by using conventional clinical procedure in pigs. RESULTS: ELP (500 µM) was proved to be the optimal injectable submucosal injection solution and elevated mucosa more efficiently than any control. The same concentration of ELP exhibited an equivalent effectiveness of mucosal elevation, the retention of the elevation, and minimal bleeding with sodium hyaluronate. The ESD procedure time with 500 µM ELP in a preclinical study with pigs was significantly shorter than with any other concentration of ELP and normal saline solution. CONCLUSIONS: Use of ELP as submucosal injection solution was feasible, with higher and longer-lasting elevation and fewer adverse events.

IL-37b gene transfer enhances the therapeutic efficacy of mesenchumal stromal cells in DSS-induced colitis mice.

AIM: To investigate whether the transfer of the IL-37b gene, a newly identified inhibitor of both innate and adaptive immunity, could improve the therapeutic efficacy of mesenchumal stromal cells (MSCs) in inflammatory bowel disease (IBD). METHODS: The expression of IL-37 in biopsied specimens of the patients with active ulcerative colitis (UC) was detected using RT-PCR and immunohistochemistry. Mice were treated with 3% dextran sulfate sodium (DSS) for 8 days to induce colitis. Before DSS treatment, the mice were injected with MSCs, MSC-eGFP or MSC-IL37b. Their body weight was measured each day, and the colons and spleens were harvested on d 10 for pathological and biochemical analyses. RESULTS: In biopsied specimens of the patients with active UC, the expression of IL-37 was dramatically elevated in inflamed mucosa, mainly in epithelial cells and infiltrating immune cells. Compared to MSC-eGFP or MSCs, MSC-IL37b administration significantly attenuated the body weight and colon length reduction, and decreased the histological score in DSS-induced colitis mice. Furthermore, MSC-IL37b administration increased the percentage of myeloid-derived suppressor cells (MDSCs) among total splenic mononuclear cells as well as the percentage of regulatory T cells (Tregs) among splenic CD4+ T cells in the mice. Moreover, MSC-IL37b administration increased the IL-2+ cells and decreased the IFN-γ+ cells among splenic CD4+ T cells. CONCLUSION: IL-37 is involved in the pathophysiology of UC. IL-37b gene transfer enhances the therapeutic efficacy of MSCs in DSS-induced colitis mice by inducing Tregs and MDSCs and regulating cytokine production.

Programming of the development of tumor-promoting neutrophils by mesenchymal stromal cells.

BACKGROUND/AIMS: Neutrophils obtain immunosuppressive function during tumor development, yet the mechanisms are largely unknown. This study explored whether and how mesenchymal stromal cells (MSCs), the key component of tumor microenvironment, regulate the suppressive function of neutrophils. METHODS: Immunosuppressive function of neutrophils was evaluated by T cell proliferation assay and 4T1 breast tumor model; molecular mechanisms were explored by transcriptional profiling, Real-time RT-PCR, arginase activity assay, and iNOS inhibition experiments. RESULTS: After being cocultured with MSCs primed by TNF-α (TNF-MSCs), CD11b(+)Ly6G(+) neutrophils isolated from bone marrow of normal mice or spleen of tumor-bearing mice obtained immunosuppressive function to inhibit T cell proliferation in vitro, and to enhance 4T1 tumor progression in vivo. Moreover, arginase activity and expression of iNOS, saa3, some cytokines and chemokines and their receptors, were upregulated in neutrophils after co-culture with TNF-MSCs. Inhibition of iNOS activity attenuated the suppressive effect of TNF-MSC pre-cocultured neutrophils on T cell proliferation. CONCLUSION: MSCs program neutrophils into an immunosuppressive and tumor-promoting phenotype.

Exploring the molecular mechanisms and shared gene signatures between celiac disease and ulcerative colitis based on bulk RNA and single-cell sequencing: Experimental verification.

Many immune-mediated diseases have the common genetic basis, as an autoimmune disorder, celiac disease (CeD) primarily affects the small intestine, and is caused by the ingestion of gluten in genetically susceptible individuals. As for ulcerative colitis (UC), which most likely involves a complex interplay between some components of the commensal microbiota and other environmental factors in its origin. These two autoimmune diseases share a specific target organ, the bowel. The etiology and immunopathogenesis of both conditions characterized by chronic intestinal inflammation, ulcerative colitis and celiac disease, are not completely understood. Both are complex diseases with genetics and the environmental factors contributing to dysregulation of innate and adaptive immune responses, leading to chronic inflammation and disease. This study is designed to further clarify the relationship between UC and CeD. The GEO database was used to download gene expression profiles for CeD (GSE112102) and UC (GSE75214). The GSEA KEGG pathway analysis revealed that immune-related pathways were significantly associated with both diseases. Further, we screened 187 shared differentially expressed genes (DEGs) of the two diseases. Gene Ontology (GO) and WikiPathways were carried out to perform the biological process and pathway enrichment analysis. Subsequently, based on the DEGs, the least absolute shrinkage and selection operator (LASSO) analysis was performed to screen for the diagnostic biomarkers of the diseases. Moreover, single-cell RNA-sequencing (RNA-seq) data from five colonic propria with UC showed that REG4 expression was present in Goblet cell, Enteroendocrine cell, and Epithelial. Finally, our work identified REG4 is the shared gene of UC and CeD via external data validation, cellular experiments, and immunohistochemistry. In conclusion, our study elucidated that abnormal immune response could be the common pathogenesis of UC and CeD, and REG4 might be a key potential biomarker and therapeutic target for the comorbidity of these two diseases.

Microbial metabolite deoxycholic acid-mediated ferroptosis exacerbates high-fat diet-induced colonic inflammation.

High-fat diet (HFD) has long been recognized as risk factors for the development and progression of ulcerative colitis (UC), but the exact mechanism remained elusive. Here, HFD increased intestinal deoxycholic acid (DCA) levels, and DCA further exacerbated colonic inflammation. Transcriptome analysis revealed that DCA triggered ferroptosis pathway in colitis mice. Mechanistically, DCA upregulated hypoxia-inducible factor-2α (HIF-2α) and divalent metal transporter-1 (DMT1) expression, causing the ferrous ions accumulation and ferroptosis in intestinal epithelial cells, which was reversed by ferroptosis inhibitor ferrostatin-1. DCA failed to promote colitis and ferroptosis in intestine-specific HIF-2α-null mice. Notably, byak-angelicin inhibited DCA-induced pro-inflammatory and pro-ferroptotic effects through blocking the up-regulation of HIF-2α by DCA. Moreover, fat intake was positively correlated with disease activity in UC patients consuming HFD, with ferroptosis being more pronounced. Collectively, our findings demonstrated that HFD exacerbated colonic inflammation by promoting DCA-mediated ferroptosis, providing new insights into diet-related bile acid dysregulation in UC.

Design, synthesis and structure-activity relationships of novel non-ketolides: 9-Oxime clarithromycin featured with seven-to thirteen-atom-length diamine linkers at 3-OH.

We report here on the structure-activity relationships of hybrids combining 3-descladinosyl clarithromycin with quinolones linked by extended diamine connectors. Several hybrids, exemplified by 23Bc, 23Be, 23Bf, 26Be, and 30Bc, not only restored potency against inducibly resistant pathogens but also exhibited significantly enhanced activities against constitutively resistant strains of Staphylococcus pneumoniae and Staphylococcus pyogenes, which express high-level resistance independent of clarithromycin or erythromycin induction. Additionally, the novel hybrids showed susceptibility against Gram-negative Haemophilus influenzae. Notably, hybrid 23Be demonstrated dual modes of action by inhibiting both protein synthesis and DNA replication in vitro and in vivo. Given these promising characteristics, 23Be emerges as a potential candidate for the treatment of community-acquired bacterial pneumonia.