Exosomes-mediated Transfer of miR-125a/b in Cell-to-cell Communication: A Novel Mechanism of Genetic Exchange in the Intestinal Microenvironment

Circulating lung cancer exosomes damage the niche of intestinal stem cells

Background

Cancer-associated weight loss occurs frequently in patients with advanced lung cancer. Many studies have demonstrated that tumor-derived exosomes could mediate the interplay between tumor cells and distal organs. In this study, we explored the interaction between lung cancer cell-derived exosomes (LCCDEs) and the niche of intestinal stem cells (ISCs).

Methods

Lewis lung carcinoma-1 (LLC1)-conditional medium (LLC1-CM), N,N'-Bis[5-(2,3-dihydro-1H-indol-1-yl)pentyl]-1,6-hexanediamine (GW4869)-conditional medium (GW4869-CM), LCCDEs and phosphate-buffered saline (PBS) were used to treat 6- to 8-week-old healthy male C57BL/6J mice (18-22 g) and B6.129P2-Lgr5tm1(cre/ERT2)Cle/J (Lgr5-EGFP-IRES-creERT2) mice (Lgr5-EGFP mice). Additionally, enteroids were treated with LLC1-CM, A549 human lung adenocarcinoma cells (A549)-CM, LCCDEs of LLC1 cells and A549 cells and PBS. LCCDEs were characterized by transmission electron microscopy, Western blot, and nanoparticle tracking analysis. The influence of LCCDEs on intestine and ISCs was explored by hematoxylin & eosin staining, proliferation, differentiation, enteroid culture, and quantitative polymerase chain reaction. PKH26-labeled LCCDEs were detected in intestinal epithelial cell line 6 (IEC-6) cells and Lgr5-EGFP mice. The changes of ISCs' niche caused by LCCDEs were examined by p-S6, pERK1/2 and p-STAT3 immunostaining.

Results

LLC1-CM damaged the small intestines and small intestinal organoids. The inhibition of exosomes by GW4869 partially alleviated these effects. Purified LCCDEs altered the structure of the intestines, changed the proliferation and differentiation of ISCs and inhibited the growth of enteroids. In addition, PKH26-labeled LCCDEs entered the cytoplasm of IECs and Paneth cells and changed the messenger ribonucleic acid (mRNA) expression of many genes, including stem cell marker genes, growth factor genes, and epithelial marker genes. Mechanistically, LCCDEs decreased mTORC1 activity in Paneth cells and inhibited p-ERK1/2 signaling in ISCs.

Conclusions

We demonstrated that circulating exosomes derived from lung cancer could impair ISCs and alter their niche in mice, which further explained the interaction between lung cancer and the gastrointestinal tract. This study proposes a promising and novel therapy to overcome weight loss in patients by decreasing LCCDEs secretion and blocking their binding to the intestine, which might be a feasible therapeutic approach in future clinical practice.

Bacteroides Fragilis Transplantation Reverses Reproductive Senescence by Transporting Extracellular Vesicles Through the Gut-Ovary Axis

The diverse and dynamic population of microorganisms present in the gut microbiota may affect host health. There are evidences to support the role of gut microbiota as a key player in reproductive development. Unfortunately, the relationship between reproductive disorders caused by aging and gut microbiota remains largely unknown. Here, it is shown for the first time that gut microorganism Bacteroides fragilis (BF) transplantation ameliorates ovarian aging by transporting extracellular vesicles (EVs) through the gut-ovary axis. Mechanistically, miR-1246 is enriched in EVs derived from BF-treated intestinal cells, and these miR-1246-enriched EVs are transferred to ovaries, thereby effectively improving reproductive senescence by reducing oxidative stress in the ovaries. Specifically, miR-1246 reduces the ubiquitination of p62 and stabilizes the protein level of p62 by targeting E3 ligase SKP2. Then Keap1-Nrf2 complex is dissociated and Keap1 is recruited to form the p62-Keap1 complex. With the dissociation of Keap1-Nrf2 complex, Nrf2 is released and activated, thus promoting the transcription of antioxidant enzymes and relieving reproductive senescence. Collectively, the data indicates that intestinal cell-derived EVs serve as natural information carriers in the crosstalk between the gut and the ovary, and intestinal microorganism transplantation is a promising approach for the treatment of ovarian dysfunction diseases.

Multi-omics revealed that the postbiotic of hawthorn-probiotic alleviated constipation caused by loperamide in elderly mice

Background

Constipation is a prevalent and recurrent gastrointestinal disorder causing significant discomfort. However, current treatments often prove ineffective. Previous research indicates that the postbiotic derived from a combination of hawthorn and probiotics can alleviate constipation. This study aimed to investigate its mechanisms using loperamide-induced constipation in aged KM mice.

Methods

Constipated mice were divided into groups receiving 10% lactulose (Y), hawthorn extract (S), probiotics (F), and the postbiotic of hawthorn-probiotic (FS). UPLC–MS metabolomics identified constituents of F, S, and FS. Network pharmacological analysis identified targets affected by FS. RT-qPCR assessed target expression in mouse colons, along with IL-6 and IL-17A levels. Molecular docking with AutoDock Tools1.5.6 evaluated interactions between FS components and targets. ex vivo colonic organ culture and RT-qPCR assessed target changes. Molecular dynamics analysis further scrutinized interactions. Targeted metabolomics measured short-chain fatty acid levels in mouse stool.

Results

UPLC–MS metabolomics revealed distinct profiles for F, S, and FS, with FS showing decreased toxic substances and increased beneficial ones compared to S. Network pharmacology identified 20 cross-targets of FS in constipation. RT-qPCR showed decreased NR1I2 and SULT1A1 and increased GLP-2r in FS-treated mice. Inflammatory cytokines IL-6 and IL-17A were also reduced. ex vivo colonic organ culture and molecular docking identified effective combinations such as TNF-Baicalin and AQP3-Quinacridone. RMSD, RMSF, and RG analyses indicated favorable interactions between small molecules and targets. Targeted metabolomics revealed differing short-chain fatty acid contents in feces among groups.

Conclusion

The postbiotic of hawthorn-probiotic alleviates constipation by regulating intestinal water and sodium metabolism, maintaining the intestinal barrier and gut flora, promoting epithelial cell proliferation, reducing inflammatory responses, and improving short-chain fatty acid metabolism.

N, Huang J, Li Y, Zhao G, Liu M. Exosome tropism and various pathways in lung cancer metastasis

Lung cancer, characterized by its high morbidity and mortality rates, has the capability to metastasize to various organs, thereby amplifying its detrimental impact and fatality. The metastasis of lung cancer is a complex biological phenomenon involving numerous physiological transformations. Exosomes, small membranous vesicles enriched with biologically active components, are pivotal in mediating intercellular communication and regulating physiological functions due to their specificity and stability. Extensive research has elucidated the production and functions of exosomes in cancer contexts. Multitude of evidence demonstrates a strong association between lung cancer metastasis and exosomes. Additionally, the concept of the pre-metastatic niche is crucial in the metastatic process facilitated by exosomes. This review emphasizes the role of exosomes in mediating lung cancer metastasis and their impact on the disease's development and the progression to other tissues. Furthermore, it explores the potential of exosomes as biomarkers for lung cancer metastasis, offering significant insights for future clinical advancements.

Posttranscriptional Regulation of Intestinal Mucosal Growth and Adaptation by Noncoding RNAs in Critical Surgical Disorders

The human intestinal epithelium has an impressive ability to respond to insults and its homeostasis is maintained by well-regulated mechanisms under various pathophysiological conditions. Nonetheless, acute injury and inhibited regeneration of the intestinal epithelium occur commonly in critically ill surgical patients, leading to the translocation of luminal toxic substances and bacteria to the bloodstream. Effective therapies for the preservation of intestinal epithelial integrity and for the prevention of mucosal hemorrhage and gut barrier dysfunction are limited, primarily because of a poor understanding of the mechanisms underlying mucosal disruption. Noncoding RNAs (ncRNAs), which include microRNAs (miRNAs), long ncRNAs (lncRNAs), circular RNAs (circRNAs), and small vault RNAs (vtRNAs), modulate a wide array of biological functions and have been identified as orchestrators of intestinal epithelial homeostasis. Here, we feature the roles of many important ncRNAs in controlling intestinal mucosal growth, barrier function, and repair after injury-particularly in the context of postoperative recovery from bowel surgery. We review recent literature surrounding the relationships between lncRNAs, microRNAs, and RNA-binding proteins and how their interactions impact cell survival, proliferation, migration, and cell-to-cell interactions in the intestinal epithelium. With advancing knowledge of ncRNA biology and growing recognition of the importance of ncRNAs in maintaining the intestinal epithelial integrity, ncRNAs provide novel therapeutic targets for treatments to preserve the gut epithelium in individuals suffering from critical surgical disorders.

The effects of tumor-derived exosomes enriched with miRNA-211a on B16F10 cells

Introduction

Exosomes have emerged as a novel alternative delivery system for transporting small molecules. Tumor-derived exosomes (TEXs) possess anti-cancer properties and serve as natural carriers of microRNAs. Using this knowledge as a foundation, the current study evaluated the efficacy of delivering a miR-211 mimic via B16F10 cell-derived exosomes to block the growth and development of a melanoma cell line.

Material and methods

After exposing B16F10 cultured cells to serum-free media for 24 hours, we collected the supernatant. Subsequently, we purified the exosomes from the supernatant using a commercial kit. Scanning electron microscopy, transmission electron microscopy, dynamic light scattering, Western blot, and bicinchoninic acid protein assay were used to characterize exosomes. Following that, miR-211 mimic was loaded into exosomes (termed TEXomiR) via a modified calcium chloride procedure. The assessment of miR-211a loading efficiency into exosomes was conducted by analyzing its relative expression. MTT, annexin V/PI, and quantitative real-time polymerase chain reaction were used to measure the proliferation, apoptosis and relative expression of miR-211 target genes, respectively.

Results

Our study showed that the exosomes can deliver miR-211 mimic efficiently. The treatment of B16F10 cells with miR-211-enriched TEX downregulated miR-211 target genes, including brain-specific homeobox, vascular endothelial growth factor, and transforming growth factor-β receptor. The results indicated the antiproliferative effect of TEXomiR as time-dose-dependent. The flow cytometry evaluation showed that TEXomiR could induce the apoptosis of B16F10 cells.

Conclusions

Our data indicated that exosomes can be suitable carriers for miR-211 mimic. Moreover, TEXomiR via anti-cancer effects could inhibit the progression of melanoma cancer.

Circular RNAs in non-alcoholic fatty liver disease: Functions and clinical significance

Nonalcoholic fatty liver disease (NAFLD), which affects approximately 25% of the global population, is an urgent health issue leading to various metabolic comorbidities. Circular RNAs (circRNAs), covalently closed RNA molecules, are characterized by ubiquity, diversity, stability, and conservatism. Indeed, they participate in various biological processes via distinct mechanisms that could modify the natural history of NAFLD. In this review, we briefly introduce the biogenesis, characteristics, and biological functions of circRNAs. Furthermore, we summarize circRNAs expression profiles in NAFLD by intersecting seven sequencing data sets and describe the cellular roles of circRNAs and their potential advantages as biomarkers of NAFLD. In addition, we emphatically discuss the exosomal non-coding RNA sorting mechanisms and possible functions in recipient cells. Finally, we extensively discuss the potential application of targeting disease-related circRNAs and competing endogenous RNA networks through gain-of-function and loss-of-function approaches in targeted therapy of NAFLD.

Predictive Potential of Biomarkers of Intestinal Barrier Function for Therapeutic Management with Teduglutide in Patients with Short Bowel Syndrome

INTRODUCTION

The human intestinal tract reacts to extensive resection with spontaneous intestinal adaptation. We analyzed whether gene expression analyses or intestinal permeability (IP) testing could provide biomarkers to describe regulation mechanisms in the intestinal barrier in short bowel syndrome (SBS) patients during adaptive response or treatment with the glucagon-like peptide-2 analog teduglutide.

METHODS

Relevant regions of the GLP-2 receptor gene were sequenced. Gene expression analyses and immunohistochemistry were performed from mucosal biopsies. IP was assessed using a carbohydrate oral ingestion test.

RESULTS

The study includes 59 SBS patients and 19 controls. Increases in gene expression with teduglutide were received for sucrase-isomaltase, sodium/glucose cotransporter 1, and calcium/calmodulin serine protein kinase. Mannitol recovery was decreased in SBS but elevated with teduglutide (Δ 40%), showed a positive correlation with remnant small bowel and an inverse correlation with parenteral support.

CONCLUSIONS

Biomarkers predicting clinical and functional features in human SBS are very limited. Altered specific gene expression was shown for genes involved in nutrient transport but not for genes controlling tight junctions. However, mannitol recovery proved useful in describing the absorptive capacity of the gut during adaptation and treatment with teduglutide.

Potential Mechanisms of Gut-Derived Extracellular Vesicle Participation in Glucose and Lipid Homeostasis

The intestine participates in the regulation of glucose and lipid metabolism in multiple facets. It is the major site of nutrient digestion and absorption, provides the interface as well as docking locus for gut microbiota, and harbors hormone-producing cells scattered throughout the gut epithelium. Intestinal extracellular vesicles are known to influence the local immune response, whereas their roles in glucose and lipid homeostasis have barely been explored. Hence, this current review summarizes the latest knowledge of cargo substances detected in intestinal extracellular vesicles, and connects these molecules with the fine-tuning regulation of glucose and lipid metabolism in liver, muscle, pancreas, and adipose tissue.

The mmu_circRNA_37492/hsa_circ_0012138 function as potential ceRNA to attenuate obstructive renal fibrosis

Circular RNAs (circRNAs) are involved in the pathogenesis of certain renal diseases, however, the function and mechanism of them in renal fibrosis remains largely unknown. In the present study, RNA expression data in unilateral ureteral obstruction (UUO) kidneys was obtained from our previous circRNA Microarray and public Gene Expression Omnibus datasets to construct a ceRNA network. The effects of target circRNA as long as the homologous human circRNA on renal fibrosis was examined in vitro and in vivo. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was further performed among genes regulated by the human circRNA. We found that circRNA_37492, showing well connection degree in the ceRNA network, was abundant expression and high sequence conservation. We observed that the expression of circRNA_37492 was induced by the TGF-β1 or UUO in BUMPT cells and C57BL/6 mice, respectively. In vitro, cytoplasmic circRNA_37492 inhibited type I, III collagen and fibronectin deposition by sponging miR-7682-3p and then upregulated its downstream target Fgb. In vivo, overexpression of circRNA_37492 attenuated fibrotic lesions in the kidneys of UUO mice via targeting miR-7682-3p/Fgb axis. Furthermore, hsa_circ_0012138, homologous with circRNA_37492, may potentially target miR-651-5p/FGB axis in human renal fibrosis. Not only that, GO and KEGG enrichment revealed that hsa_circ_0012138-regulated genes were previously demonstrated to related to the fibrosis. In conclusion, we for the first time demonstrated that circRNA_37492 attenuated renal fibrosis via targeting miR-7682-3p/Fgb axis, and the homologous hsa_circRNA_0012138 was speculated as a possible ceRNA to regulate multiple gene expressions and involve in human renal fibrosis, suggesting that circRNA_37492/hsa_circ_0012138 may serve as potent therapy target for obstructive renal fibrosis disease.

Exosome-mediated miR-7-5p delivery enhances the anticancer effect of Everolimus via blocking MNK/eIF4E axis in non-small cell lung cancer

Everolimus is a kind of mammalian target of rapamycin (mTOR) inhibitors. Activated mitogen-activated protein kinase interacting kinases/eukaryotic translation initiation factor 4E (MNK/eIF4E) axis plays a crucial role in resistance to Everolimus in non-small cell lung cancer (NSCLC). The eIF4E phosphorylation increased by mTOR inhibitors is mainly mediated by MNKs. However, the mechanisms are poorly understood. Recently, extensive reprogramming of miRNA profiles has also been found after long-term mTOR inhibitor exposure. Our previous studies have confirmed that tumor suppressor miR-7-5p is decreased in A549 cells after treatment with Everolimus. Exactly, MNK1 is the target of miR-7-5p. In this study, we investigated the biological functions and potential molecular mechanisms of miR-7-5p in the NSCLC undergoing treatment with Everolimus. We confirmed that Everolimus targeted mTORC1 inducing NSCLC cells to secrete miR-7-5p-loaded exosomes in Rab27A and Rab27B-dependent manners. Loss of intracellular miR-7-5p induced phosphorylation of MNK/eIF4E axis, but a supplement of extra exosomal miR-7-5p could reverse it. Of note, both low expression of miR-7-5p and elevated MNK1 protein were associated with a poor prognosis of NSCLC. Both endogenous miR-7-5p and exo-miR-7-5p enhanced the therapeutic efficacy of Everolimus by inhibiting the proliferation, migration, and metastasis of NSCLC in vitro and in vivo. The combination of miR-7-5p with Everolimus induced apoptosis to exhibit a synergistic anticancer therapeutic efficacy through dual abrogation of MNK/eIF4E and mTOR in NSCLC. In conclusion, Everolimus decreases the intracellular miR-7-5p by releasing of miR-7-5p loaded exosomes from NSCLC cells in Rab27A and Rab27B dependent manners. Either endogenous miR-7-5p or exo-miR-7-5p combined with Everolimus can enhance the anticancer efficacy by targeting MNK/eIF4E axis and mTOR. Besides, both low levels of miR-7-5p and positive expression of MNK1 act as independent poor prognostic biomarkers for NSCLC. Therefore, restoring miR-7-5p carried by exosome may be a promising novel combined therapeutic strategy with Everolimus for NSCLC.

Tumor-derived exosomes encapsulating miR-34a promote apoptosis and inhibit migration and tumor progression of colorectal cancer cells under in vitro condition

BACKGROUND

MicroRNA (miR)-34a, as a master tumor suppressor in colorectal cancer (CRC), could regulate multiple genes participating in tumor proliferation, invasion, immune evasion, and inflammation-induced progression. Exosomes, as novel nano-carriers, were found to be capable of shuttling crucial mediators to various cells. Since the conventional CRC therapeutics currently are a matter of debate, implication of microRNAs in malignancy remedies have been addressed illustrating promising outlooks.

OBJECTIVES

In this study, we aimed to investigate the delivery of miR-34a to CRC cell line CT-26 by encapsulating into tumor-derived exosomes (TEXs), in order to evaluate the anti-proliferative and progressive effects of the novel nano-carrier complex under in vitro condition.

METHODS

Exosomes were purified from the starved CT-26 cells and then enriched by miR-34a using the calcium chloride (Cacl2) modified solution. Following the detection of miR-34a expression in the enriched TEXs, the viability of CT-26 cells treated by multiplicity concentrations of either TEXs or TEX-miR-34a was examined. Moreover, the apoptosis rate of the cells was evaluated, and the migration of CT-26 cells subjected to both TEX-miR-34a and TEX was also measured. Thereafter, the expressions of miR-34a target genes, as IL-6R, STAT3, PD-L1, and VEGF-A, which play roles in tumor progression, were determined in the treated CT-26 cells.

RESULTS

The viability of CT-26 cells was harnessed following the treatment with TEX-miR-34a and the apoptosis levels of the cells were also observed to be enhanced dose-dependently. TEX-miR-34a was able to diminish the migration rate of the TEX-miR-34a treated cells and the expressions of IL-6R, STAT3, PD-L1, and VEGF-A were significantly restricted. Moreover, TEXs alone increased the apoptosis rate of tumor cells and repressed the proliferation and migration of these cells which were boosted by enrichment of TEXs with miR-34a.

CONCLUSION

Exosomes isolated from the starved CT-26 cells were found to have a potential to deliver miR-34a into tumor cells properly with high functionality maintenance for miR-34a in case of regulating genes related to tumor progression and TEXs which showed no positive effect favoring cancer cells, presumably act as a favorable adjuvant in the CRC therapy.

Therapeutic potential of an intestinotrophic hormone, glucagon-like peptide 2, for treatment of type 2 short bowel syndrome rats with intestinal bacterial and fungal dysbiosis

Background

Previous studies showed that type 2 short bowel syndrome (SBS) rats were accompanied by severe intestinal bacterial dysbiosis. Limited data are available for intestinal fungal dysbiosis. Moreover, no effective therapeutic drugs are available for these microbiota dysbiosis. The aims of our study were to investigate the therapeutic potential of glucagon-like peptide 2 (GLP-2) for these microbiota dysbiosis in type 2 SBS rats.

Methods

8-week-old male SD rats which underwent 80% small bowel resection, ileocecum resection, partial colon resection and jejunocolostomy, were treated with saline (SBS group, n = 5) or GLP-2 (GLP2.SBS group, n = 5). The Sham group rats which underwent transection and re-anastomosis were given a saline placebo (Sham group, n = 5). 16S rRNA and ITS sequencing were applied to evaluate the colonic bacterial and fungal composition at 22 days after surgery, respectively.

Results

The relative abundance of Actinobacteria, Firmicutes and proinflammatory Proteobacteria increased significantly in SBS group rats, while the relative abundance of Bacteroidetes, Verrucomicrobia and Tenericutes decreased remarkably. GLP-2 treatment significantly decreased Proteus and increased Clostridium relative to the saline treated SBS rats. The diversity of intestinal fungi was significantly increased in SBS rats, accompanied with some fungi abnormally increased and some resident fungi (e.g., Penicillium) significantly decreased. GLP-2 treatment significantly decreased Debaryomyces and Meyerozyma, and increased Penicillium. Moreover, GLP-2 partially restored the bacteria-fungi interkingdom interaction network of SBS rats.

Conclusion

Our study confirms the bacterial and fungal dysbiosis in type 2 SBS rats, and GLP-2 partially ameliorated these microbiota dysbiosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06270-w.

MiR-221/222 Ameliorates Deoxynivalenol-Induced Apoptosis and Proliferation Inhibition in Intestinal Epithelial Cells by Targeting PTEN

Intestinal epithelial cells are critical for nutrient absorption and defending against pathogen infection. Deoxynivalenol (Don), the most common mycotoxin, contaminates cereals and food throughout the world, causes serious damage to mammal intestinal mucosa, and appears as intestinal epithelial cell apoptosis and proliferation inhibition. Our previous study has found that milk-derived exosome ameliorates Don-induced intestinal damage, but the mechanism is still not fully understood. In this study, we demonstrated that Don downregulated the expression of miR-221/222 in intestinal epithelial cells, and exosome treatment reversed the inhibitory effect of Don on miR-221/222. Through immunofluorescence and flow cytometry analysis, we identified that miR-221/222 ameliorates Don-induced apoptosis and proliferation inhibition in intestinal epithelial cells. Through bioinformatics analyses and RNA immunoprecipitation analysis, we identified Phosphatase and tensin homolog (PTEN) is the target of miR-221/222. Through the PTEN interfering experiment, we found Don-induced apoptosis and proliferation inhibition relied on PTEN. Finally, through adenovirus to overexpress miR-221/222 in mice intestinal epithelial cells specifically, our results showed that miR-221/222 ameliorated Don-induced apoptosis and proliferation inhibition in intestinal epithelial cells by targeting PTEN. This study not only expands our understanding of how miR-221/222 and the host gene PTEN regulate intestinal epithelial cells defending against Don-induced damage, but also provides a new way to protect the development of the intestine.

Power and promise of exosomes as clinical biomarkers and therapeutic vectors for liquid biopsy and cancer control

Exosomes, microvesicles derived from the nuclear endosome and plasma membrane, can be released into the extracellular environment to act as mediators between the cell membrane and cytoplasmic proteins, lipids, or RNA. Exosomes are considered effective carriers of intercellular signals in prokaryotes and eukaryotes, because of their ability to efficiently transfer proteins, lipids, and nucleic acids between cellular compartments. Since the 2007 discovery that exosomes carry bioactive substances, exosomes have been intensively researched. In various physiological and pathological processes, exosomes play important biological roles by specifically combining with receptor cells and transmitting information. Their stable biological characteristics, diversity of contents, non-invasiveness path for introducing signaling molecules, and ability for rapid detection make exosomes a promising clinical diagnostic marker for potentially many pathological conditions, including cancers. Exosomes are not only considered biomarkers and prognostic disease factors, but also have potential as gene carriers and drug delivery vectors, and have important clinical significance and application potential in the fields of cancer diagnosis, prognosis, and treatment.