Lactulose, a galactose-fructose disaccharide, is made from the milk sugar lactose by heating or isomerization processes. Lactulose is proposed to modulate gut microbiota and thus expected to be beneficial in treating inflammatory bowel disease. In the present study, we investigated the therapeutic effect of lactulose on gastrointestinal inflammation and inflammation-related tumorigenesis in a mouse model of colorectal cancer as well as its effect on gut microbiota composition. Azoxymethane (AOM)/dextran sulfate sodium (DSS) model was used in this study. Lactulose treatment was performed by feeding 2% lactulose for 14 weeks. Stool samples collected at 4 time points were used for metagenomic analysis of the microbiota. Pathological analysis was performed 21 weeks after AOM injection. AOM/DSS increased the macrophage counts, inflammatory cytokine expression, colorectal tumorigenesis, and imbalance in gut microbiota composition, as evidenced by increased pathogen abundance (e.g., Escherichia and Clostridium). Lactulose significantly inhibited the inflammatory events, and ameliorated inflammation and tumorigenesis. The composition of the intestinal microbiota was also restored upon lactulose treatment, and lactulose reduced pathogen abundance and increased the abundance of Muribaculum and Lachnospiraceae. Meanwhile, the pathways related to Crohn’s disease were downregulated after lactulose treatment. Our findings suggest that lactulose restores the structure and composition of the intestinal microbiota, mitigates inflammation, and suppresses inflammatory tumorigenesis.

Chronic inflammation is a risk factor for colorectal cancer, and inflammatory cytokines secreted from inflammatory cells and active oxygen facilitate tumorigenesis. Intestinal bacteria are thought to regulate tumorigenesis. The longer the breastfeeding period, the lower is the risk of inflammatory bowel disease. Here, we investigated preventive effects of the probiotic Lactobacillus rhamnosus M9 (Probio-M9) on colitis-associated tumorigenesis. An inflammatory colorectal tumor model was established using a 6-week-old male C57BL/6NCrSlc mouse, which was intraperitoneally administered with azoxymethane (AOM: 12 mg/kg body weight). On weeks 2 and 4, 2% dextran sulfate sodium (DSS) was administered to mice for 7 days through drinking water. On weeks 8 and 10, Probio-M9 (2 × 10⁹/day) was orally administered for 7 days. Animals were sacrificed at 20 weeks after AOM administration and immunohistochemical staining and Western blotting was performed. The α-diversity of microflora (Shannon index), principal coordinate analysis, and distribution of intestinal bacterium genera and metabolic pathways were compared. The AOM/DSS group showed weight loss, diarrhea, intestinal shortening, increased number of colon tumors, proliferating tumorigenesis, increased inflammation score, fibrosis, increased CD68+, or CD163+ macrophage cells in the subserosal layer of non-tumor areas. Inflammation and tumorigenesis ameliorated after Probio-M9 treatment. Fecal microbial functions were altered by AOM/DSS treatment. Probio-M9 significantly upregulated the fecal microbial diversity and reversed fecal microbial functions. Thus, Probio-M9 could suppress tumor formation in the large intestine by regulating the intestinal environment and ameliorating inflammation, suggesting its therapeutic potential for treatment of inflammation and colitis-associated tumorigenesis.

Intestinal bacteria play important roles in the progression of colitis-associated carcinogenesis. Colostrum-derived Lacticaseibacillus rhamnosus Probio-M9 (Probio-M9) has shown a protective effect in a colitis-associated cancer (CAC) model, but detailed metagenomic analysis had not been performed. Here, we investigated the preventive effects of the probiotic Probio-M9 on CAC-model mice, tracking the microbiota. Feces were obtained at four time points for evaluation of gut microbiota. The effect of Probio-M9 on tight junction protein expression was evaluated in co-cultured Caco-2 cells. Probio-M9 treatment decreased the number of tumors as well as stool consistency score, spleen weight, inflammatory score, and macrophage expression in the CAC model. Probio-M9 accelerated the recovery of the structure, composition, and function of the intestinal microbiota destroyed by azoxymethane (AOM)/dextran sulfate sodium (DSS) by regulating key bacteria (including Lactobacillus murinus, Muribaculaceae bacterium DSM 103720, Muribaculum intestinale, and Lachnospiraceae bacterium A4) and pathways from immediately after administration until the end of the experiment. Probio-M9 co-culture protected against lipopolysaccharide-induced impairment of tight junctions in Caco-2 cells. This study provides valuable insight into the role of Probio-M9 in correcting gut microbiota defects associated with inflammatory bowel disease carcinogenesis and may have clinical application in the treatment of inflammatory carcinogenesis.

Background: Intestinal microbiota plays an important role in the progression of pulmonary hypertension (PH). Colostrum-derived Lacticaseibacillus rhamnosus Probio-M9 (Probio-M9) has shown protective effects against inflammation and remodeling. We investigated whether Probio-M9 supplementation could improve the pathology of PH. Methods: The monocrotaline (MCT)-induced PH model rats are created followed by Probio-M9 treatment. Microbiota and pathological analyses were performed to investigate the therapeutic effects of Probio-M9. Results: Probio-M9 significantly suppressed cardiovascular remodeling and reduced mortality in rats. Analysis of the fecal microbiota revealed that Probio-M9 significantly altered the gut microbiota of MCT model rats. Specifically, Alistipes sp009774895 and Duncaniella muris populations increased, whereas Limosilactobacillus reuteri_D, Ligilactobacillus apodeme and Monoglobus sp900542675 decreased compared to those in the MCT group. Focusing on the expression of GPNMB in macrophages and the localization of CD44, we found that the number of these cells increased in the MCT group but significantly decreased with Probio-M9 treatment. In lung tissue from PH patients, more GPNMB-positive macrophages were found than non-PH lungs, and an increase in CD44-positive cells was confirmed in the vicinity of GPNMB. Conclusions: Probio-M9 had a significant impact on the intestinal microbiota and GPNMB/CD44 positive cells in the lungs of PH rats.

Background: Postoperative colorectal cancer (CRC) patients may benefit from both conventional nutritional support and culturally specific Traditional Chinese Medicine (TCM) dietary guidance, yet no validated instrument specifically assesses their TCM dietary knowledge and educational needs. This study aimed to develop and preliminarily validate the Postoperative Colorectal Cancer TCM Diet Questionnaire (PCRC-TDQ) for assessing postoperative CRC patients’ TCM dietary knowledge and educational needs. Methods: An initial 40-item pool was generated through literature review, multidisciplinary discussion, qualitative interviews, two rounds of Delphi expert consultation with 20 experts, and pilot testing, resulting in a 30-item preliminary questionnaire. The questionnaire was administered to 252 postoperative CRC patients, and 250 valid questionnaires were included in the psychometric analysis. Item analysis, content-validity assessment, exploratory factor analysis (EFA), and reliability testing were conducted. Results: Three items (K6, N7, and N9) were removed after exploratory factor analysis (EFA), resulting in the final 27-item PCRC-TDQ comprising 19 knowledge items and eight needs items. The PCRC-TDQ contained two conceptual domains (TCM dietary knowledge and dietary needs), with four underlying factors identified within these domains, explaining 51.43% of the total variance. Item-level content validity indices ranged from 0.88 to 1.00, and the scale-level content validity index/average was 0.990. Cronbach’s alpha was 0.899 for the total instrument, 0.913 for the knowledge domain, and 0.849 for the needs domain. Conclusion: The 27-item PCRC-TDQ demonstrated satisfactory preliminary content validity, structural validity, internal consistency, and test–retest reliability in the study sample. It may serve as a preliminary assessment tool during initial postoperative dietary consultations to identify TCM dietary knowledge gaps and educational needs. Independent structural validation, including confirmatory factor analysis in separate cohorts, and multicenter validation are required before routine clinical implementation.