Intake of Pro- and/or Prebiotics as a Promising Approach for Prevention and Treatment of Colorectal Cancer

Novel selenium-enriched Pichia kudriavzevii as a dietary supplement to alleviate dextran sulfate sodium-induced colitis in mice by modulating the gut microbiota and host metabolism

Inflammatory bowel disease (IBD) poses persistent challenges due to its chronic and recurrent nature, exacerbated by the unsatisfactory outcomes of the traditional treatment approaches. In this study, we developed a dietary supplement, selenium-enriched Pichia kudriavzevii (SeY), to alleviate dextran sulfate sodium-induced colitis in mice. The newly developed functional food shows dual-functional activity, acting both as a probiotic and a reliable source of organic selenium. This study aimed to investigate the preventive effects of SeY against dextran sulfate sodium-induced colitis in mice and elucidate the underlying mechanisms. Results showed that SeY, especially at high doses (HSeY), significantly ameliorated colitis symptoms, reduced colonic damage, attenuated inflammatory responses, and mitigated oxidative stress. Furthermore, HSeY strengthened intestinal barrier function by increasing goblet cell numbers, upregulating MUC2 expression, and enhancing tight junction proteins (ZO-1, claudin-1, and occludin). Additionally, HSeY alleviated gut microbiota dysbiosis by promoting the colonization of beneficial bacteria such as norank-f-Muribaculaceae and Bacteroides, while suppressing harmful microorganisms such as norank-f-norank-o-Clostridia-UCG-014. The altered gut microbiota also affected gut metabolism, with differential metabolites primarily associated with amino acids, such as tryptophan metabolism, contributing to the mitigation of oxidative stress and inflammatory responses. Further studies involving antibiotic-mediated depletion of gut flora and fecal microbiota transfer trials corroborated that the preventive effect of HSeY against IBD relied on the gut microbiota. This study provides vital insights into colitis prevention and advances selenium-enriched fortified food-targeted nutritional interventions.

Dietary supplementation with novel selenium-enriched Pichia kudriavzevii regulates gut microbiota and host metabolism in mice

Insufficient selenium intake can lead to serious health problems. However, most research on the functional properties of selenium-enriched probiotics has focused on sub-health conditions or disease models, with limited studies involving healthy subjects. Additionally, previous research has primarily explored the direct effects of selenium itself, neglecting its influence on gut microbiota and metabolism. This study aimed to explore whether long-term intake of Pichia kudriavzevii enriched with selenium affected gut microbiota and host metabolism in mice and to identify microbiota and metabolites related to beneficial outcomes. Results demonstrated that selenium-enriched P. kudriavzevii (SeY) exhibited non-toxic properties, did not cause colon or liver damage, enhanced antioxidant capacity, and reduced inflammation in a selenium dose-dependent manner. Additionally, SeY supplementation significantly altered the gut microbiota. High-dose SeY (HSeY) elevated the abundance of beneficial bacteria such as Lactobacillus and suppressed harmful bacteria such as Eubacterium nodatum group, Prevotellaceae_NK3B31_group, and unclassified_f__Lachnospiraceae. Low-dose SeY (LSeY) increased the abundance of Faecalibaculum. The strain without enriched selenium exhibited higher levels of Akkermansia compared to selenium-enriched strains. Both strains, with or without enriched selenium, stimulated the production of short-chain fatty acids. Non-targeted metabolomics analysis revealed that HSeY treatment regulated various metabolic pathways, such as tryptophan metabolism, tyrosine metabolism, and arginine biosynthesis. LSeY treatment modulated tyrosine metabolism, secondary bile acid metabolism, bile secretion, and primary bile acid metabolism. P. kudriavzevii regulated the metabolism of purine, arginine, proline, and tryptophan. Our study highlights the promise of SeY supplementation in regulating host metabolism and the gut microbiota, offering insights into its implications for promoting health.

Ethyl cinnamate suppresses tumor growth through anti-angiogenesis by attenuating VEGFR2 signal pathway in colorectal cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Kaempferia galanga Linn. is an aromatic medicinal herb with extensively applied in India, China, Malaysia and other South Asia countries for thousands of years. It has been mentioned to treat abdominal tumors. Ethyl cinnamate (EC), one of the main chemical constituents of the rhizome of K. galanga, exhibited nematocidal, sedative and vasorelaxant activities. However, its anti-angiogenic activity, and anti-tumor effect have not been investigated.

AIM OF THE STUDY

To investigate the anti-angiogenic mechanism of EC and its anti-tumor effect by suppressing angiogenesis.

MATERIALS AND METHODS

The in vitro anti-angiogenic effect was evaluated using HUVECs model induced by VEGF and zebrafish model in vivo. The influence of the EC on phosphorylation of VEGFR2 and its downstream signaling pathways were evaluated by western blotting assay. Molecule docking technology was conducted to explore the interaction between EC and VEGFR2. SPR assay was used for detecting the binding affinity between EC and VEGFR2. To further investigate the molecular mechanism of EC on anti-angiogenesis, VEGFR2 knockdown in HUVECs and examined the influence of the EC. Anti-tumor activity of EC was evaluated using colony formation assay and apoptosis assay. The inhibitory effect of EC on tumor growth was explored using HT29 colon cancer xenograft model.

RESULTS

EC obviously inhibited proliferation, migration, invasion and tube formation of VEGF-induced HUVECs. EC also induced apoptosis of HUVECs. Moreover, it inhibited the development of vessel formation in zebrafish. Further investigations demonstrated that EC could suppress the phosphorylation of VEGFR2, and its downstream signaling pathways were altered in VEGF-induced HUVECs. EC formed a hydrogen bond to bind with the ATP binding site of the VEGFR2, and EC-VEGFR2 interaction was shown in SPR assay. The suppressive effect of EC on angiogenesis was abrogated after VEGFR2 knockdown in HUVECs. EC inhibited the colon cancer cells colony formation and induced apoptosis. In addition, EC suppressed tumor growth in colon cancer xenograft model, and no detectable hepatotoxicity and nephrotoxicity. In addition, it inhibited the phosphorylation of VEGFR2, and its downstream signal pathways in tumor.

CONCLUSIONS

EC could inhibit tumor growth in colon cancer by suppressing angiogenesis via VEGFR2 signaling pathway, and suggested EC as a promising candidate for colon cancer treatment.

Comprehensive distribution and species of selenium in Se-enriched Pichia kudriavzevii 1845

This study is the first to demonstrate the yeast Pichia kudriavzevii can effectively deliver Se and investigate the distribution and species of Se in Se-enriched P. kudriavzevii. Results showed that P. kudriavzevii can accumulate Se and convert 84.883% of absorbed Se into organic forms, of which 78.338% was incorporated into protein, 1.978% combined with polysaccharides, and 0.456% bound to nucleic acid. Besides, water-soluble, salt-soluble, and alkali-soluble proteins account for 49.398%, 1.867%, and 20.628% of selenoprotein, respectively. The dominant Se species were SeCys2 and MeSeCys. Additionally, Se-enrichment enhanced nutritional value of P. kudriavzevii by increasing the levels of amino acids, iron, and zinc. The activity of key rate-limiting enzyme sephosphate synthetase involved in Se biotransformation was improved after Se enrichment. The extracellular pH results suggest that Se enrichment ability can be further enhanced by elevating pH. These results suggest P. kudriavzevii holds great promise as an effective vehicle for delivering Se.

Cellular and Molecular Mechanisms of the Tumor Stroma in Colorectal Cancer: Insights into Disease Progression and Therapeutic Targets

Colorectal cancer (CRC) is a major health burden worldwide and is the third most common type of cancer. The early detection and diagnosis of CRC is critical to improve patient outcomes. This review explores the intricate interplay between the tumor microenvironment, stromal interactions, and the progression and metastasis of colorectal cancer. The review begins by assessing the gut microbiome's influence on CRC development, emphasizing its association with gut-associated lymphoid tissue (GALT). The role of the Wnt signaling pathway in CRC tumor stroma is scrutinized, elucidating its impact on disease progression. Tumor budding, its effect on tumor stroma, and the implications for patient prognosis are investigated. The review also identifies conserved oncogenic signatures (COS) within CRC stroma and explores their potential as therapeutic targets. Lastly, the seed and soil hypothesis is employed to contextualize metastasis, accentuating the significance of both tumor cells and the surrounding stroma in metastatic propensity. This review highlights the intricate interdependence between CRC cells and their microenvironment, providing valuable insights into prospective therapeutic approaches targeting tumor-stroma interactions.