Sodium butyrate inhibits colitis-associated colorectal cancer through preventing the gut microbiota dysbiosis and reducing the expression of NLRP3 and IL-1β

Free fatty acid receptors type 2 and 4 mediate the anticancer effects of fatty acids in colorectal cancer - in vitro and in vivo studies

High incidence of colorectal cancer (CRC) is influenced by diet low in fiber (source of short chain fatty acids, SCFAs, natural agonists for free fatty acid receptor type 2 (FFAR2)) and high in fat (main source of long chain fatty acids, LCFAs, FFAR4 agonists). FFAR2 and FFAR4 are downregulated in CRC. In this study, we characterized whether the anticancer effects of SCFAs and LCFAs are FFAR-dependent in in vitro and in vivo models of CRC. In vitro, SW-480 cell growth was determined after incubation with FFARs ligands (SCFAs: acetate, butyrate; LCFAs: palmitate, stearate) using MTT assay. Cell migration and invasion were investigated by wound healing and transwell-based invasion assays. In vivo, SCFAs and LCFAs were administered to azoxymethane/dextran sodium sulfate-treated mice. Real-time qPCR and Western blot were used to determine FFARs expression. SCFAs and LCFAs significantly decreased SW-480 cell growth, migration and invasion capacities. Combination of SCFAs and LCFAs induced synergistic inhibitory effects on CRC cell growth and motility. FFAR2 and FFAR4 expression were elevated in CRC cells treated with butyrate as well as with butyrate+acetate, and butyrate+palmitate+stearate. Concurrently, only FFAR4 expression was increased in CRC cells incubated with LCFAs. In vivo, treatment with LCFAs, but not SCFAs increased ffar2 and Ffar4 expression. Our findings showed that SCFAs and LCFAs inhibit cancer cell growth and their migration and invasion capabilities. Our study evidenced that the anticancer effects of SCFAs- and LCFAs are mediated by FFAR2 and FFAR4.

Current understanding of free fatty acids and their receptors in colorectal cancer treatment

Colorectal cancer (CRC) is one of the leading causes of cancer-related death. Currently, dietary factors are being emphasized in the pathogenesis of CRC. There is strong evidence that fatty acids (FAs) and free FA receptors (FFARs) are involved in CRC. This comprehensive review discusses the role of FAs and their receptors in CRC pathophysiology, development, and treatment. In particular, butyrate and n-3 polyunsaturated fatty acids have been found to exert anticancer properties by, among others, inhibiting proliferation and metastasis and inducing apoptosis in tumor cells. Consequently, they are used in conjunction with conventional therapies. Furthermore, FFAR gene expression is down-regulated in CRC, suggesting their suppressive character. Recent studies showed that the FFAR4 agonist, GW9508, can inhibit tumor growth. In conclusion, natural as well as synthetic FFAR ligands are considered promising candidates for CRC therapy.

Bio-study: Modeling of natural nanomolecules as a nanocarrier surface for antioxidant and glucose biosensor

The nature of nano molecules as a self-assembled nanocomposite surface depends on the nanoparticles of sodium butyrate, cellulose, and pycnogenol; the synthesis is achieved via precipitation and grinding methods. The excellent functionalized surface of nanocomposite (NCP) enables the loading of the selected drugs, where the efficiency of the NCP surface arrived at 92.2 %. The electrochemical behavior emphasized the success of a functionalized NCP surface for incorporation with drugs for the drug delivery system, the results of cytotoxicity detect the effect of NCP on the mouse normal liver (BNL) cells, where the high and low concentrations on the BNL cells have a safe dose. Cell viability with BNL cells was reported at 101.8 % with10 μL and 100.12 % with 100 μL, the interaction between the NCP and the human serum albumin (HSA) at room temperature. The low interaction rate with the glutamate and increased binding with the oxidized glutathione disulfide (GSSG) and reduced glutathione (SGH) reflect the antioxidant activity of NCP. The strong binding of NCP with biomolecules such as glucose is referred to as the biosensor property. The results recommend that NCP is an excellent nanocarrier for drug delivery and glucose biosensors for diabetes.

Saccharomyces cerevisiae SC-2201 Attenuates AOM/DSS-Induced Colorectal Cancer by Modulating the Gut Microbiome and Blocking Proinflammatory Mediators

Colorectal cancer is the third most common cancer in the world today, and studies have shown that the ratio of Candida to Saccharomyces cerevisiae increased, and the abundance of S. cerevisiae in the intestines of patients with colorectal cancer decreased, which suggests that there is an imbalance in the proportion of fungi in the intestines of patients with colorectal cancer. The objective of this study was to screen S. cerevisiae isolate from traditional Chinese fermentation starters and assess its ability to ameliorate dysbiosis and to alleviate the carcinogenic process of azoxymethane/dextran sodium sulfate-induced colorectal cancer in mice model. S. cerevisiae strain SC-2201 was isolated and exhibited probiotic properties, including the ability to survive in an acidic pH environment and in the presence of bile salts in the gastrointestinal tract, as well as antioxidant activities. Oral administration of S. cerevisiae SC-2201 not only alleviated weight loss but also reduced colonic shortening and histological damage in azoxymethane/dextran sodium sulfate-induced colorectal cancer in mice. Furthermore, the administration of S. cerevisiae SC-2201 suppressed the expression of proinflammatory mediators, such as interleukin-1β, interleukin-6, cyclooxygenase-2, vascular endothelial growth factor, nucleotide-binding domain, leucine-rich repeat, and pyrin domain-containing protein 3. Specifically, the analysis of gut bacteriome showed a significant decrease in Bacteroidota and Campylobacterota levels, as well as an increase in Proteobacteria level in the colorectal cancer group, which was alleviated by supplementation with S. cerevisiae SC-2201. The analysis of the mycobiome revealed a significant increase in the levels of Basidiomycota, Apiosordaria, Naganishia, and Taphrina genera in the colorectal cancer group, which were alleviated after supplementation with S. cerevisiae SC-2201. However, the levels of Xenoramularia, Entoloma, and Keissleriella were significantly increased after administration with S. cerevisiae SC-2201. Overall, the findings of this study demonstrate that S. cerevisiae SC-2201 possesses potential probiotic properties and can effectively attenuate the development of colorectal cancer, highlighting its cancer-preventive potential. This is the first report of a S. cerevisiae strain isolated from traditional Chinese fermentation starters which showed good probiotic properties, and mitigated azoxymethane/dextran sodium sulfate-induced colorectal cancer by modulating the gut microbiome and blocking proinflammatory mediators in mice.

Modulating Gut Microbiota Prevents Anastomotic Leak to Reduce Local Implantation and Dissemination of Colorectal Cancer Cells after Surgery

PURPOSE

Anastomotic leak (AL) is a major complication in colorectal cancer surgery and consists of the leakage of intestinal content through a poorly healed colonic wound. Colorectal cancer recurrence after surgery is a major determinant of survival. We hypothesize that AL may allow cancer cells to escape the gut and lead to cancer recurrence and that improving anastomotic healing may prevent local implantation and metastatic dissemination of cancer cells.

EXPERIMENTAL DESIGN

We investigated the association between AL and postoperative outcomes in patients with colorectal cancer. Using mouse models of poor anastomotic healing, we assessed the processes of local implantation and dissemination of cancer cells. The effect of dietary supplementation with inulin and 5-aminosalicylate (5-ASA), which activate PPAR-γ in the gut, on local anastomotic tumors was assessed in mice undergoing colonic surgery. Inulin and 5-ASA were also assessed in a mouse model of liver metastasis.

RESULTS

Patients experiencing AL displayed lower overall and oncologic survival than non-AL patients. Poor anastomotic healing in mice led to larger anastomotic and peritoneal tumors. The microbiota of patients with AL displays a lower capacity to activate the antineoplastic PPAR-γ in the gut. Modulation of gut microbiota using dietary inulin and 5-ASA reinforced the gut barrier and prevented anastomotic tumors and metastatic spread in mice.

CONCLUSIONS

Our findings reinforce the hypothesis that preventing AL is paramount to improving oncologic outcomes after colorectal cancer surgery. Furthermore, they pave the way toward dietary targeting of PPAR-γ as a novel way to enhance healing and diminish cancer recurrence.

Egg Yolk Lipids Alleviated Dextran Sulfate Sodium-Induced Colitis by Inhibiting NLRP3 Inflammasome and Regulating Gut Microbiota

The increasing incidence of inflammatory bowel disease (IBD) has become a global phenomenon. Egg yolk lipids are one of the essential dietary foods, but its effects on intestinal immunity remain unclear. Here, egg yolk lipids are obtained using ethanol extraction and a total of 601 kinds of lipids are detected via lipidomics, including 251 kinds of triglycerides, 133 kinds of phosphatidylcholines, 44 kinds of phosphatidylethanolamines. Then, the study finds that egg yolk lipids significantly alleviate dextran sulfate sodium-induced colitis and reduce the production of inflammatory factors. Meanwhile, egg yolk lipids also maintain intestinal barrier integrity and decrease lipopolysaccharide translocation by alleviating intestinal structure damage and increasing the numbers of goblet cells and mucin 2. Mechanistically, egg yolk lipids attenuate colitis by inhibiting the assembly and activation of NLRP3 inflammasome. Moreover, the study also finds that egg yolk lipids reverse gut microbiota dysbiosis referring to increased relative abundance of Bacteroides acidifaciens and decrease relative abundance of Akkermansia muciniphila, as well as increased short chain fatty acids concentration in the gut. Together, the study elucidates the anti-colitis effect of egg yolk lipids and provides positive evidences for egg yolk lipids involving in dietary strategy and IBD therapy.

Determination of short-chain fatty acids as putative biomarkers of cancer diseases by modern analytical strategies and tools: a review

Short-chain fatty acids (SCFAs) are the main metabolites produced by bacterial fermentation of non-digestible carbohydrates in the gastrointestinal tract. They can be seen as the major flow of carbon from the diet, through the microbiome to the host. SCFAs have been reported as important molecules responsible for the regulation of intestinal homeostasis. Moreover, these molecules have a significant impact on the immune system and are able to affect inflammation, cardiovascular diseases, diabetes type II, or oncological diseases. For this purpose, SCFAs could be used as putative biomarkers of various diseases, including cancer. A potential diagnostic value may be offered by analyzing SCFAs with the use of advanced analytical approaches such as gas chromatography (GC), liquid chromatography (LC), or capillary electrophoresis (CE) coupled with mass spectrometry (MS). The presented review summarizes the importance of analyzing SCFAs from clinical and analytical perspective. Current advances in the analysis of SCFAs focused on sample pretreatment, separation strategy, and detection methods are highlighted. Additionally, it also shows potential areas for the development of future diagnostic tools in oncology and other varieties of diseases based on targeted metabolite profiling.

The Multifaceted Role and Regulation of Nlrp3 Inflammasome in Colitis-Associated Colo-Rectal Cancer: A Systematic Review

Colitis-associated colo-rectal cancer remains the leading cause of mortality in inflammatory bowel diseases, with inflammation remaining one of the bridging points between the two pathologies. The NLRP3 inflammasome complex plays an important role in innate immunity; however, its misregulation can be responsible for the apparition of various pathologies such as ulcerative colitis. Our review focuses on the potential pathways of upregulation or downregulation of the NLRP3 complex, in addition to evaluating its role in the current clinical setting. Eighteen studies highlighted the potential pathways of NLRP3 complex regulation as well as its role in the metastatic process in colo-rectal cancer, with promising results. Further research is, however, needed in order to validate the results in a clinical setting.

Sodium Butyrate Induces CRC Cell Ferroptosis via the CD44/SLC7A11 Pathway and Exhibits a Synergistic Therapeutic Effect with Erastin

Colorectal cancer (CRC) is one of the most common malignancies, and effective treatment and prevention methods are lacking. Sodium butyrate (NaB) is a short-chain fatty acid produced by intestinal microbial fermentation of dietary fiber. It has been shown to be effective in inhibiting CRC, but the mechanism is not known.

METHODS

Human normal intestinal epithelial cell line FHT and colorectal tumor cell line HCT-116 were treated with NaB alone or in combination with different programmed cell death inhibitors. Cell activity was then assessed with MTT assays and PI staining; ferroptosis with Fe²⁺, glutathione (GSH), and lipid peroxidation assays; signaling pathway screening with PCR arrays; and CD44, SCL7A11, and GPX4 expression with Western blotting. A CD44-overexpressing HCT-116 cell line was constructed to determine the effect of the overexpression of CD44 on NaB-induced ferroptosis. The synergistic effect of co-treatment with NaB and Erastin was assessed by isobolographic analysis.

RESULTS

NaB induced apoptosis and ferroptosis in HCT-116 cells but only induced low-level apoptosis in FHC cells. Moreover, NaB significantly increased intracellular Fe²⁺ and promoted GSH depletion and lipid peroxidation in HCT-116 cells. Ferroptosis-related qPCR array analysis identified CD44/SLC7A11 as a potential effector molecular of NaB-induced ferroptosis. NaB significantly inhibited the expression of CD44 and SLC7A11 in mouse CRC tissues. A CD44 overexpressed HCT-116 cell line was used to verify that CD44/SLC7A11 was a key signaling pathway that NaB-induced GSH depletion, lipid peroxidation accumulation, and ferroptosis in HCT-116 cells. Examination of whether NaB can increase the effect of ferroptosis agents showed that NaB, in combination with Erastin, a ferroptosis inducer, further promoted HCT-116 cell death and increased changes of ferroptosis markers.

CONCLUSIONS

Our results suggest that NaB induces ferroptosis in CRC cells through the CD44/SLC7A11 signaling pathway and has synergistic effects with Erastin. These results may provide new insights into CRC prevention and the combined use of NaB and ferroptosis-inducing agents.

Microbial short-chain fatty acids: a strategy to tune adoptive T cell therapy

The gut microbiota and its metabolites have been shown to play a pivotal role in the regulation of metabolic, endocrine and immune functions. Though the exact mechanism of action remains to be fully elucidated, available knowledge supports the ability of microbiota-fermented short-chain fatty acids (SCFAs), such as acetate, propionate, and butyrate, to influence epigenetic and metabolic cascades controlling gene expression, chemotaxis, differentiation, proliferation, and apoptosis in several non-immune and immune cell subsets. While used as preferred metabolic substrates and sources of energy by colonic gut epithelial cells, most recent evidence indicates that these metabolites regulate immune functions, and in particular fine-tune T cell effector, regulatory and memory phenotypes, with direct in vivo consequences on the efficacy of chemotherapy, radiotherapy and immunotherapy. Most recent data also support the use of these metabolites over the course of T cell manufacturing, paving the way for refined adoptive T cell therapy engineering. Here, we review the most recent advances in the field, highlighting in vitro and in vivo evidence for the ability of SCFAs to shape T cell phenotypes and functions.