Although anti-inflammatory effects of American ginseng metabolites have been investigated at systemic and cellular levels, the biological signatures of ginseng microbial metabolite-induced bioactivities are still unknown. To fill this knowledge gap and to support the findings published in the companion research article entitled "American ginseng microbial metabolites attenuated DSS-induced colitis and abdominal pain" (Wang et al., 2018), we are here to provide datasets of enteric microbiome biotransformation and fecal metabolomics. For the microbiome biotransformation study, data were obtained from C57BL6 mice treated with a broad-spectrum antibiotic metronidazole. After oral administration of ginseng extract, we observed that compound K (CK) was undetectable in metronidazole-treated mouse stools but was detected in stools from vehicle-treated mice, suggesting biotransformation of CK is gut microbial dependent. In the fecal metabolomic study, three small molecules which were associated with gut inflammation were identified. In the DSS mice, the levels of lactate, linoleic acid, and malic acid increased significantly in the model group. After ginseng treatment, the expressions of these metabolites reduced significantly. Thus, the selective fecal endogenous metabolites could be used as biological signatures reflecting severity of enteric inflammation and ginseng treatment outcomes. Our results showed the enteric microbiome plays a key role for CK conversion, and the effects of CK on enteric inflammation can be demonstrated by the metabolomics data.

Chronic inflammation is involved in the development of colon cancer by inducing mutations and aberrant DNA methylation in colon epithelial cells. Furthermore, there is growing evidence showing that the colonic microbiota modulates the inflammation response in the host and influences colon tumorigenesis. However, the influence of the colonic microbiota on aberrant DNA methylation remains unknown. Here, we show the effect of colonic microbes on DNA methylation and tumorigenicity using a mouse model of human ulcerative colitis. Mice treated with azoxymethane (AOM) and dextran sulfate sodium (DSS) showed an increase in degree of colitis, as estimated by body weight, occult blood, and stool consistency/diarrhea at 2 weeks after treatment, but treatment with antibiotics markedly reduced the severity of the colitis. Although mucosal hyperplasia and increased inflammation-related genes were observed in the colonic epithelial cells of the AOM/DSS-treated mice, treatment with antibiotics abrogated these changes. In addition, treatment with antibiotics significantly decreased the number of mucosal nodules from 5.9 ± 5.3 to 0.2 ± 0.6 (P < 0.01) and area of occupancy from 50.1 ± 57.4 to 0.5 ± 1.4 mm2 (P < 0.01). Aberrant DNA methylation of three marker CpG islands (Cbln4, Fosb and Msx1) was induced by AOM/DSS treatment in colonic mucosae, but this increase was suppressed by 50% to 92% (P < 0.05) with antibiotic treatment. Microbiome analysis showed that this change was associated with a decrease of the Clostridium leptum subgroup. These data demonstrate that antibiotics suppressed tumorigenesis through inhibition of aberrant DNA methylation induced by chronic inflammation. This article is protected by copyright. All rights reserved.

Clostridium difficile infection (CDI) is an increasingly common occurrence in the hospital setting, and it is associated with significant morbidity and mortality. In vitro studies have found that rifaximin, a nonabsorbable rifamycin antibiotic, displays potent antimicrobial activity against C. difficile. This systematic review thus aimed to examine the clinical role of rifaximin in CDI. Using the keywords [clostridium OR difficile OR colitis] AND [rifaximin OR xifaxan OR rifagut], a preliminary search on the PubMed, EMBASE, Medline, Clinicaltrials.gov and Google Scholar databases yielded 6210 papers published in English between 1-Jan-1988 and 1-Jul-2018. A total of eight clinical trials were systematically reviewed. Of these, only two were randomized, controlled trials. In the treatment of mild-moderate CDI, rifaximin is a viable alternative to existing therapies (metronidazole or vancomycin). More importantly, rifaximin has a potential role in conjunction with other therapies, showing to be efficacious in reducing the rate of CDI recurrence. However, clinical studies have reported a resistance rate in the range of 29.1-48.9%, with a geographical variance in the distribution of rifaximin-resistant C. difficile strains. With its unique eubiotic properties and positive modulation of the gut flora, rifaximin has a potential therapeutic role in the management of CDI, especially in CDI recurrences. As there is a paucity of randomized, controlled trials to support its use, studies with larger and more diverse populations should be conducted before the efficacy of rifaximin can be conclusively stated. Rifaximin is also a relatively expensive antimicrobial, further studies should include cost-benefit analyses.

Klebsiella oxytoca hemorrhagic colitis is a rare form of antibiotic associated hemorrhagic colitis that is Clostridium difficile negative. Klebsiella oxytoca colitis has been shown to be triggered by penicillin administration, yet other antibiotics have been implicated as well. It can mimic the appearance of ischemic colitis on endoscopy; however it will generally be found in young, otherwise healthy patients without risk factors. We present a case of a 33-year-old Caucasian female who presented to the emergency room with profuse, bloody diarrhea for 5 days, after a one-week course of ampicillin. Colonoscopy was notable for ulcerated mucosa with erythema and easy friability and the biopsy was suggestive of ischemic colitis. Stool culture was positive for many Klebsiella oxytoca. The patient was discharged home with resolution of symptoms after three days in the hospital. She was instructed to avoid penicillin antibiotics and minimize nonsteroidal anti-inflammatory drug use.

Clostridium difficile infection (CDI) causes nosocomial/antibiotic-associated diarrhea and pseudomembranous colitis, with dramatic incidence/mortality worldwide. C. difficile virulence factors are toxin A and toxin B (TcdB) which cause cytopathic/cytotoxic effects and inflammation. Until now studies were focused on molecular effects of C. difficile toxins (Tcds) on different cells while unexplored aspect is the status/fate of cells that survived their cytotoxicity. Recently we demonstrated that enteric glial cells (EGCs) are susceptible to TcdB cytotoxicity, but several EGCs survived and were irreversibly cell-cycle arrested and metabolically active, suggesting that EGCs could became senescent. This is important because allowed us to evaluate the not explored status/fate of cells surviving Tcds cytotoxicity, and particularly if TcdB induces senescence in EGCs. Rat-transformed EGCs were treated with 10 ng/ml TcdB for 6 h-48 h, or for 48 h, followed by incubation for additional 4 or 11 days in absence of TcdB (6 or 13 total days). Senescence markers/effectors were examined by specific assays. TcdB induces senescence in EGCs, as demonstrated by the senescence markers: irreversible cell-cycle arrest, senescence-associated-β‑galactosidase positivity, flat morphology, early and persistent DNA damage (ATM and H2AX phosphorylation), p27 overexpression, pRB hypophosphorylation, c‑Myc, cyclin B1, cdc2 and phosphorylated-cdc2 downregulation, Sirtuin‑2 and Sirtuin‑3 overexpression. TcdB-induced EGC senescence is dependent by JNK and AKT activation but independent by ROS, p16 and p53/p21 pathways. In conclusion, TcdB induces senescence in EGCs. The extrapolation of these results to CDI leads to hypothesize that EGCs that survived TcdB, once they have acquired a senescence state, could cause irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and tumors due to persistent inflammation, transfer of senescence status and stimulation of pre-neoplastic cells.

No information is available on the use of eravacycline during breastfeeding.The manufacturer states that breastfeeding is not recommended during treatment and for 4 days after the last dose. However, based on the excretion of other tetracycline antibiotics and the high protein binding of eravacycline, amounts in milk are expected to be low and probably poorly absorbed orally by the breastfed infant. If an infant is breastfed, monitor the infant for possible effects on the gastrointestinal flora, such as diarrhea, candidiasis (e.g., thrush, diaper rash) or rarely, blood in the stool indicating possible antibiotic-associated colitis. As a theoretical precaution, avoid prolonged or repeat courses during nursing.