RESUMO
BACKGROUND AND AIMS: The molecular mechanisms underlying successful fecal microbiota transplantation (FMT) for recurrent Clostridioides difficile infection (rCDI) remain poorly understood. The primary objective of this study was to characterize alterations in microRNAs (miRs) following FMT for rCDI. METHODS: Sera from 2 prospective multicenter randomized controlled trials were analyzed for miRNA levels with the use of the Nanostring nCounter platform and quantitative reverse-transcription (RT) polymerase chain reaction (PCR). In addition, rCDI-FMT and toxin-treated animals and ex vivo human colonoids were used to compare intestinal tissue and circulating miRs. miR inflammatory gene targets in colonic epithelial and peripheral blood mononuclear cells were evaluated by quantitative PCR (qPCR) and 3'UTR reporter assays. Colonic epithelial cells were used for mechanistic, cytoskeleton, cell growth, and apoptosis studies. RESULTS: miRNA profiling revealed up-regulation of 64 circulating miRs 4 and 12 weeks after FMT compared with screening, of which the top 6 were validated in the discovery cohort by means of RT-qPCR. In a murine model of relapsing-CDI, RT-qPCR analyses of sera and cecal RNA extracts demonstrated suppression of these miRs, an effect reversed by FMT. In mouse colon and human colonoids, C difficile toxin B (TcdB) mediated the suppressive effects of CDI on miRs. CDI dysregulated DROSHA, an effect reversed by FMT. Correlation analyses, qPCR ,and 3'UTR reporter assays revealed that miR-23a, miR-150, miR-26b, and miR-28 target directly the 3'UTRs of IL12B, IL18, FGF21, and TNFRSF9, respectively. miR-23a and miR-150 demonstrated cytoprotective effects against TcdB. CONCLUSIONS: These results provide novel and provocative evidence that modulation of the gut microbiome via FMT induces alterations in circulating and intestinal tissue miRs. These findings contribute to a greater understanding of the molecular mechanisms underlying FMT and identify new potential targets for therapeutic intervention in rCDI.
Assuntos
MicroRNA Circulante/sangue , Infecções por Clostridium/terapia , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Intestinos/microbiologia , Reinfecção , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , MicroRNA Circulante/genética , Infecções por Clostridium/sangue , Infecções por Clostridium/genética , Infecções por Clostridium/microbiologia , Modelos Animais de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Técnicas de Cultura de Tecidos , Transcriptoma , Resultado do TratamentoRESUMO
A library of flavonol analogues was synthesised and evaluated as potential anticancer agents against a human prostate cancer cell line, 22rν1. Compounds 3, 8 and 11 (IC(50) 2.6, 3.3 and 4.0 µM respectively) showed potent cancer cell growth inhibition, comparable to the lead compound 3',4',5'-trimethoxyflavonol (1) (IC(50) 3.1 µM) and superior to the naturally occurring flavonols quercetin (16) and fisetin (22) (both >15 µM). Results indicate that the 3',4',5'- arrangement of either hydroxy (OH) or methoxy (OMe) residues is important for growth arrest of these cells and that the OMe analogues may be superior to their OH counterparts. Compounds 1, 3, 8 and 11 warrant further investigation as potential agents for the management of prostate cancer.