n-6 Linoleic Acid Induces Epigenetics Alterations Associated with Colonic Inflammation and Cancer

The Potential of Integrative Cancer Treatment Using Melatonin and the Challenge of Heterogeneity in Population-Based Studies: A Case Report of Colon Cancer and a Literature Review

Melatonin is a multifunctional hormone regulator that maintains homeostasis through circadian rhythms, and desynchronization of these rhythms can lead to gastrointestinal disorders and increase the risk of cancer. Preliminary clinical studies have shown that exogenous melatonin alleviates the harmful effects of anticancer therapy and improves quality of life, but the results are still inconclusive due to the heterogeneity of the studies. A personalized approach to testing clinical parameters and response to integrative treatment with nontoxic and bioavailable melatonin in patient-centered N-of-1 studies deserves greater attention. This clinical case of colon cancer analyzes and discusses the tumor pathology, the adverse effects of chemotherapy, and the dynamics of markers of inflammation (NLR, LMR, and PLR ratios), tumors (CEA, CA 19-9, and PSA), and hemostasis (D-dimer and activated partial thromboplastin time). The patient took melatonin during and after chemotherapy, nutrients (zinc, selenium, vitamin D, green tea, and taxifolin), and aspirin after chemotherapy. The patient's PSA levels decreased during CT combined with melatonin (19 mg/day), and melatonin normalized inflammatory markers and alleviated symptoms of polyneuropathy but did not help with thrombocytopenia. The results are analyzed and discussed in the context of the literature on oncostatic and systemic effects, alleviating therapy-mediated adverse effects, association with survival, and N-of-1 studies.

Linoleic acid induces human ovarian granulosa cell inflammation and apoptosis through the ER-FOXO1-ROS-NFκB pathway

Polycystic ovary syndrome (PCOS) is a complex reproductive endocrinological disorder influenced by a combination of genetic and environmental factors. Linoleic acid (LA) is a widely consumed ω-6 polyunsaturated fatty acid, accounting for approximately 80% of daily fatty acid intake. Building upon the prior investigations of our team, which established a connection between LA levels in the follicular fluid and PCOS, this study deeply examined the specific impact of LA using a granulosa cell line. Our findings revealed that LA exerts its influence on granulosa cells (GCs) by binding to the estrogen receptor (ER). Activated ER triggers the transcription of the FOXO1 gene. Reactive oxygen species (ROS)-related oxidative stress (OS) and inflammation occur downstream of LA-induced FOXO1 activation. Increased OS and inflammation ultimately culminate in GC apoptosis. In summary, LA modulates the apoptosis and inflammation phenotypes of GCs through the ER-FOXO1-ROS-NF-κB pathway. Our study provides additional experimental evidence to comprehend the pathophysiology of PCOS and provides novel insights into the dietary management of individuals with PCOS.

Gut-brain communication mediates the impact of dietary lipids on cognitive capacity

Cognitive impairment, as a prevalent symptom of nervous system disorders, poses one of the most challenging aspects in the management of brain diseases. Lipids present in the cell membranes of all neurons within the brain and dietary lipids can regulate the cognition and memory function. In recent years, the advancements in gut microbiome research have enabled the exploration of dietary lipids targeting the gut-brain axis as a strategy for regulating cognition. This present review provides an in-depth overview of how lipids modulate cognition via the gut-brain axis depending on metabolic, immune, neural and endocrine pathways. It also comprehensively analyzes the effects of diverse lipids on the gut microbiota and intestinal barrier function, thereby affecting the central nervous system and cognitive capacity. Moreover, comparative analysis of the positive and negative effects is presented between beneficial and detrimental lipids. The former encompass monounsaturated fatty acids, short-chain fatty acids, omega-3 polyunsaturated fatty acids, phospholipids, phytosterols, fungal sterols and bioactive lipid-soluble vitamins, as well as lipid-derived gut metabolites, whereas the latter (detrimental lipids) include medium- or long-chain fatty acids, excessive proportions of n-6 polyunsaturated fatty acids, industrial trans fatty acids, and zoosterols. To sum up, the focus of this review is on how gut-brain communication mediates the impact of dietary lipids on cognitive capacity, providing a novel theoretical foundation for promoting brain cognitive health and scientific lipid consumption patterns.

Epigenetic modifications in obesity-associated diseases

The global prevalence of obesity has reached epidemic levels, significantly elevating the susceptibility to various cardiometabolic conditions and certain types of cancer. In addition to causing metabolic abnormalities such as insulin resistance (IR), elevated blood glucose and lipids, and ectopic fat deposition, obesity can also damage pancreatic islet cells, endothelial cells, and cardiomyocytes through chronic inflammation, and even promote the development of a microenvironment conducive to cancer initiation. Improper dietary habits and lack of physical exercise are important behavioral factors that increase the risk of obesity, which can affect gene expression through epigenetic modifications. Epigenetic alterations can occur in early stage of obesity, some of which are reversible, while others persist over time and lead to obesity-related complications. Therefore, the dynamic adjustability of epigenetic modifications can be leveraged to reverse the development of obesity-associated diseases through behavioral interventions, drugs, and bariatric surgery. This review provides a comprehensive summary of the impact of epigenetic regulation on the initiation and development of obesity-associated cancers, type 2 diabetes, and cardiovascular diseases, establishing a theoretical basis for prevention, diagnosis, and treatment of these conditions.

Metagenomic and targeted metabolomic analyses reveal distinct phenotypes of the gut microbiota in patients with colorectal cancer and type 2 diabetes mellitus

BACKGROUND

Type 2 diabetes mellitus (T2DM) is an independent risk factor for colorectal cancer (CRC), and the patients with CRC and T2DM have worse survival. The human gut microbiota (GM) is linked to the development of CRC and T2DM, respectively. However, the GM characteristics in patients with CRC and T2DM remain unclear.

METHODS

We performed fecal metagenomic and targeted metabolomics studies on 36 samples from CRC patients with T2DM (DCRC group, n = 12), CRC patients without diabetes (CRC group, n = 12), and healthy controls (Health group, n = 12). We analyzed the fecal microbiomes, characterized the composition and function based on the metagenomics of DCRC patients, and detected the short-chain fatty acids (SCFAs) and bile acids (BAs) levels in all fecal samples. Finally, we performed a correlation analysis of the differential bacteria and metabolites between different groups.

RESULTS

Compared with the CRC group, LefSe analysis showed that there is a specific GM community in DCRC group, including an increased abundance of Eggerthella , Hungatella , Peptostreptococcus , and Parvimonas , and decreased Butyricicoccus , Lactobacillus , and Paraprevotella . The metabolomics analysis results revealed that the butyric acid level was lower but the deoxycholic acid and 12-keto-lithocholic acid levels were higher in the DCRC group than other groups ( P < 0.05). The correlation analysis showed that the dominant bacterial abundance in the DCRC group ( Parvimonas , Desulfurispora , Sebaldella , and Veillonellales , among others) was negatively correlated with butyric acid, hyodeoxycholic acid, ursodeoxycholic acid, glycochenodeoxycholic acid, chenodeoxycholic acid, cholic acid and glycocholate. However, the abundance of mostly inferior bacteria was positively correlated with these metabolic acid levels, including Faecalibacterium , Thermococci , and Cellulophaga .

CONCLUSIONS

Unique fecal microbiome signatures exist in CRC patients with T2DM compared to those with non-diabetic CRC. Alterations in GM composition and SCFAs and secondary BAs levels may promote CRC development.

Comprehensive Investigation on Associations between Dietary Intake and Blood Levels of Fatty Acids and Colorectal Cancer Risk

BACKGROUND

Increasingly, studies have discovered that different fatty acids (Fas) are linked to colorectal cancer (CRC) risk.

METHODS

We systematically searched Embase and Medline databases to identify eligible studies that examined the associations of different types of Fas with CRC risk. The effect estimates and their 95% confidence intervals (Cis) were pooled using a random-effects model. Subgroup and sensitivity analyses were performed to examine the robustness of the study findings.

RESULTS

This study evaluated the associations of 28 dietary and 18 blood Fas with CRC risk by summarizing the most updated evidence from 54 observational and four Mendelian Randomization (MR) studies. The present findings suggested that high dietary intake of eicosapentaenoic acid (EPA), docosahexanoic acid (DHA), and docosapentaenoic acid (DPA) are related to low risk of CRC, while the n-6/n-3 PUFA ratio and trans-FA are related to high risk of CRC. The summary of all cohort studies found that a high intake of SFA and DHA was a protective factor for CRC, and a high intake of the n-6/n-3 PUFA ratio was a risk factor for CRC. In the subgroup analysis of cancer subsites, we found that the dietary intake of linoleic acid (LA) and trans-FA are risk factors, while DPA is a protective factor for colon cancer. High dietary DHA intake was associated with a lower risk of rectal cancer, while the dietary n-6/n-3 PUFA ratio was associated with a higher risk of rectal cancer. Meta-analysis of blood FA levels showed a significant reverse association between blood pentadecanoic acid and CRC risk, whilst other blood Fas showed no significant association with CRC risk. All included MR studies showed that high plasma arachidonic acid (AA) is associated with increased CRC risk.

CONCLUSIONS

Current evidence on the dietary intake and blood levels of Fas in relation to CRC risk is less consistent. Future studies are needed to investigate how the metabolism of Fas contributes to CRC development.

The Modulatory Effects of Fatty Acids on Cancer Progression

Cancer is the second leading cause of death worldwide and the global cancer burden rises rapidly. The risk factors for cancer development can often be attributed to lifestyle factors, of which an unhealthy diet is a major contributor. Dietary fat is an important macronutrient and therefore a crucial part of a well-balanced and healthy diet, but it is still unclear which specific fatty acids contribute to a healthy and well-balanced diet in the context of cancer risk and prognosis. In this review, we describe epidemiological evidence on the associations between the intake of different classes of fatty acids and the risk of developing cancer, and we provide preclinical evidence on how specific fatty acids can act on tumor cells, thereby modulating tumor progression and metastasis. Moreover, the pro- and anti-inflammatory effects of each of the different groups of fatty acids will be discussed specifically in the context of inflammation-induced cancer progression and we will highlight challenges as well as opportunities for successful application of fatty acid tailored nutritional interventions in the clinic.

Nigakinone alleviates DSS-induced experimental colitis via regulating bile acid profile and FXR/NLRP3 signaling pathways

The correlation of bile acid (BA) metabolism disorder with the pathogenesis of ulcerative colitis (UC) is realized nowadays. Farnesoid X receptor (FXR), a controller for BA homeostasis and inflammation, is a promising target for UC therapy. Nigakinone has potential therapeutic effects on colitis. Herein, we investigated the anti-UC effects and mechanism of nigakinone in colitic animals induced by dextran sulfate sodium (DSS). The related targets involved in the nucleotide-binding oligomerization domain, leucine-rich repeat, and pyrin domain-containing 3 (NLRP3) signaling pathway were measured. BA-targeted metabolomics was employed to reveal the regulatory effects of nigakinone on BA profile in colitis, while expressions of FXR and its mediated targets referring to BA enterohepatic circulation were determined. The critical role of FXR in the treatment of nigakinone for colitis was studied via molecule-docking, dual-luciferase reporter® (DLR™) assays, FXR silencing cells, and FXR knockout mice. Results showed nigakinone attenuated DSS-induced colitis symptoms, including excessive inflammatory response by NLRP3 activation, and injury of the intestinal mucosal barrier. Nigakinone regulated BA disorders by controlling cholesterol hydroxylase and transporters mediated by FXR, then decreased BA accumulation in colon. Molecular-docking and DLR™ assays indicated FXR might be a target of nigakinone. In vitro, nigakinone restrained BA-induced inflammation and cell damage via FXR activation and inhibition of inflammatory cytokines. However, ameliorating effects of nigakinone on colitis were suppressed by FXR knockout or silencing in vivo or in vitro. Taken together, nigakinone ameliorated experimental colitis via regulating BA profile and FXR/NLRP3 signaling pathway.

Cecum axis (CecAx) preservation reveals physiological and pathological gradients in mouse gastrointestinal epithelium

The mouse cecum has emerged as a model system for studying microbe-host interactions, immunoregulatory functions of the microbiome, and metabolic contributions of gut bacteria. Too often, the cecum is falsely considered as a uniform organ with an evenly distributed epithelium. We developed the cecum axis (CecAx) preservation method to show gradients in epithelial tissue architecture and cell types along the cecal ampulla-apex and mesentery-antimesentery axes. We used imaging mass spectrometry of metabolites and lipids to suggest functional differences along these axes. Using a model of Clostridioides difficile infection, we show how edema and inflammation are unequally concentrated along the mesenteric border. Finally, we show the similarly increased edema at the mesenteric border in two models of Salmonella enterica serovar Typhimurium infection as well as enrichment of goblet cells along the antimesenteric border. Our approach facilitates mouse cecum modeling with detailed attention to inherent structural and functional differences within this dynamic organ.

Effect of gut microbiota on colorectal cancer progression and treatment

Microbiota is a collection of bacteria, archaea, eukaryotes, bacteriophages, viruses, and fungi that cover human body surfaces and cavities. They characterize inside the body due to several factors such as diet, nutrition, xenobiotic substances, and microbial infections. Several studies have shown that gut microbiota can induce resistance against pathogens and regulate the immune system. In addition, their disruption is associated with several physiological and biochemical disorders, including inflammatory bowel disease (IBD), obesity, autoimmune diseases such as diabetes, hypertension, colon cancer, and cardiovascular disease. Colorectal cancer (CRC) is the third-deadliest cancer worldwide, accounting for approximately 900,000 deaths per year globally. Gut microbiota has been heavily linked to CRC incidence and prevention via bacterial metabolites, invasion, translocation, host's defense modulations, and bacterial-immune system interactions. In addition, it can influence the metabolism of chemical compounds such as drugs and xenobiotics to manipulate the treatment response in CRC patients.

Noninvasive detection and interpretation of gastrointestinal diseases by collaborative serum metabolite and magnetically controlled capsule endoscopy

Gastrointestinal diseases are complex diseases that occur in the gastrointestinal tract. Common gastrointestinal diseases include chronic gastritis, peptic ulcers, inflammatory bowel disease, and gastrointestinal tumors. These diseases may manifest a long course, difficult treatment, and repeated attacks.

Gastroscopy and mucosal biopsy are the gold standard methods for diagnosing gastric and duodenal diseases, but they are invasive procedures and carry risks due to the necessity of sedation and anesthesia. Recently, several new approaches have been developed, including serological examination and magnetically controlled capsule endoscopy (MGCE). However, serological markers lack lesion information, while MGCE images lack molecular information.

This study proposes combining these two technologies in a collaborative noninvasive diagnostic scheme as an alternative to the standard procedures. We introduce an interpretable framework for the clinical diagnosis of gastrointestinal diseases. Based on collected blood samples and MGCE records of patients with gastrointestinal diseases and comparisons with normal individuals, we selected serum metabolite signatures by bioinformatic analysis, captured image embedding signatures by convolutional neural networks, and inferred the location-specific associations between these signatures.

Our study successfully identified five key metabolite signatures with functional relevance to gastrointestinal disease. The combined signatures achieved discrimination AUC of 0.88. Meanwhile, the image embedding signatures showed different levels of validation and testing accuracy ranging from 0.7 to 0.9 according to different locations in the gastrointestinal tract as explained by their specific associations with metabolite signatures. Overall, our work provides a new collaborative noninvasive identification pipeline and candidate metabolite biomarkers for image auxiliary diagnosis. This method should be valuable for the noninvasive detection and interpretation of gastrointestinal and other complex diseases.

A Comprehensive Analysis of Microflora and Metabolites in the Development of Ulcerative Colitis into Colorectal Cancer Based on the Lung–Gut Correlation Theory

The lungs and large intestine can co-regulate inflammation and immunity through the lung–gut axis, in which the transportation of the gut microbiota and metabolites is the most important communication channel. In our previous study, not only did the composition of the gut microbiota and metabolites related to inflammation change significantly during the transition from ulcerative colitis (UC) to colorectal cancer (CRC), but the lung tissues also showed corresponding inflammatory changes, which indicated that gastrointestinal diseases can lead to pulmonary diseases. In order to elucidate the mechanisms of this lung–gut axis, metabolites in bronchoalveolar lavage fluid (BALF) and lung tissues were detected using UHPLC–Q-TOF-MS/MS technology, while microbiome characterization was performed in BALF using 16S rDNA sequencing. The levels of pulmonary metabolites changed greatly during the development of UC to CRC. Among these changes, the concentrations of linoleic acid and 7-hydroxy-3-oxocholic acid gradually increased during the development of UC to CRC. In addition, the composition of the pulmonary microbiota also changed significantly, with an increase in the Proteobacteria and an obvious decrease in the Firmicutes. These changes were consistent with our previous studies of the gut. Collectively, the microbiota and metabolites identified above might be the key markers related to lung and gut diseases, which can be used as an indication of the transition of diseases from the gut to the lung and provide a scientific basis for clinical treatment.

Enriched Riceberry Bran Oil Exerts Chemopreventive Properties through Anti-Inflammation and Alteration of Gut Microbiota in Carcinogen-Induced Liver and Colon Carcinogenesis in Rats

Riceberry has recently been acknowledged for its beneficial pharmacological effects. Riceberry bran oil (RBBO) exhibited anti-proliferation activity in various cancer cell lines. However, animal studies of RBBO on anti-carcinogenicity and its molecular inhibitory mechanism have been limited. This study purposed to investigate the chemopreventive effects of RBBO on the carcinogen-induced liver and colorectal carcinogenesis in rats. Rats were injected with diethylnitrosamine (DEN) and 1,2-dimethylhydrazine (DMH) and further orally administered with RBBO equivalent to 100 mg/kg body weight of γ-oryzanol 5 days/week for 10 weeks. RBBO administration suppressed preneoplastic lesions including hepatic glutathione S-transferase placental form positive foci and colorectal aberrant crypt foci. Accordingly, RBBO induced hepatocellular and colorectal cell apoptosis and reduced pro-inflammatory cytokine expression. Interestingly, RBBO effectively promoted the alteration of gut microbiota in DEN- and DMH-induced rats, as has been shown in the elevated Firmicutes/Bacteroidetes ratio. This outcome was consistent with an increase in butyrate in the feces of carcinogen-induced rats. The increase in butyrate reflects the chemopreventive properties of RBBO through the mechanisms of its anti-inflammatory properties and cell apoptosis induction in preneoplastic cells. This would indicate that RBBO containing γ-oryzanol, phytosterols, and tocols holds significant potential in the prevention of cancer.

Impact of the Exposome on the Epigenome in Inflammatory Bowel Disease Patients and Animal Models

Inflammatory bowel diseases (IBD) are chronic inflammatory disorders of the gastrointestinal tract that encompass two main phenotypes, namely Crohn's disease and ulcerative colitis. These conditions occur in genetically predisposed individuals in response to environmental factors. Epigenetics, acting by DNA methylation, post-translational histones modifications or by non-coding RNAs, could explain how the exposome (or all environmental influences over the life course, from conception to death) could influence the gene expression to contribute to intestinal inflammation. We performed a scoping search using Medline to identify all the elements of the exposome that may play a role in intestinal inflammation through epigenetic modifications, as well as the underlying mechanisms. The environmental factors epigenetically influencing the occurrence of intestinal inflammation are the maternal lifestyle (mainly diet, the occurrence of infection during pregnancy and smoking); breastfeeding; microbiota; diet (including a low-fiber diet, high-fat diet and deficiency in micronutrients); smoking habits, vitamin D and drugs (e.g., IBD treatments, antibiotics and probiotics). Influenced by both microbiota and diet, short-chain fatty acids are gut microbiota-derived metabolites resulting from the anaerobic fermentation of non-digestible dietary fibers, playing an epigenetically mediated role in the integrity of the epithelial barrier and in the defense against invading microorganisms. Although the impact of some environmental factors has been identified, the exposome-induced epimutations in IBD remain a largely underexplored field. How these environmental exposures induce epigenetic modifications (in terms of duration, frequency and the timing at which they occur) and how other environmental factors associated with IBD modulate epigenetics deserve to be further investigated.

Fibroblast Growth Factor 19 Improves LPS-Induced Lipid Disorder and Organ Injury by Regulating Metabolomic Characteristics in Mice

Sepsis is extremely heterogeneous pathology characterized by complex metabolic changes. Fibroblast growth factor 19 (FGF19) is a well-known intestine-derived inhibitor of bile acid biosynthesis. However, it is largely unknown about the roles of FGF19 in improving sepsis-associated metabolic disorder and organ injury. In the present study, mice were intravenously injected recombinant human FGF19 daily for 7 days followed by lipopolysaccharide (LPS) administration. At 24 hours after LPS stimuli, sera were collected for metabolomic analysis. Ingenuity pathway analysis (IPA) network based on differential metabolites (DMs) was conducted. Here, metabolomic analysis revealed that FGF19 pretreatment reversed the increase of LPS-induced fatty acids. IPA network indicated that altered linoleic acid (LA) and gamma-linolenic acid (GLA) were involved in the regulation of oxidative stress and mitochondrial function and were closely related to reactive oxygen species (ROS) generation. Further investigation proved that FGF19 pretreatment decreased serum malondialdehyde (MDA) levels and increased serum catalase (CAT) levels. In livers, FGF19 suppressed the expression of inducible NO synthase (iNOS) and enhanced the expression of nuclear factor erythroid 2-related factor 2 (NRF2) and hemeoxygenase-1 (HO-1). Finally, FGF19 pretreatment protected mice against LPS-induced liver, ileum, and kidney injury. Taken together, FGF19 alleviates LPS-induced organ injury associated with improved serum LA and GLA levels and oxidative stress, suggesting that FGF19 might be a promising target for metabolic therapy for sepsis.

Obesity, the other pandemic: linking diet and carcinogenesis by epigenetic mechanisms

Both obesity and cancer are complex medical conditions that are considered public health problems. The influence of obesity on the predisposition to develop various types of cancer has been observed in a wide variety of studies. Due to their importance as public health problems, and the close relationship between both conditions, it is important to be able to understand and associate them mechanistically. In this review article, we intend to go a little further, by finding relationships between lifestyle, which can lead a person to develop obesity, and how it influences at the cellular and molecular level, affecting gene expression to favor signaling pathways or transcriptional programs involved in cancer. We describe how products of metabolism and intermediate metabolism can affect chromatin structure, participating in the regulation (or dysregulation) of gene expression, and we show an analysis of genes that are responsive to diets high in sugar and fat, and how their epigenetic landscape is altered.

Pleiotropic roles of FXR in liver and colorectal cancers

Nuclear receptor farnesoid X receptor (FXR) is generally considered a cell protector of enterohepatic tissues and a suppressor of liver cancer and colorectal carcinoma (CRC). Loss or reduction of FXR expression occurs during carcinogenesis, and the FXR level is inversely associated with the aggressive behaviors of the malignancy. Global deletion of FXR and tissue-specific deletion of FXR display distinct effects on tumorigenesis. Epigenetic silencing and inflammatory context are two main contributors to impaired FXR expression and activity. FXR exerts its antitumorigenic function via the following mechanisms: 1) FXR regulates multiple metabolic processes, notably bile acid homeostasis; 2) FXR antagonizes hepatic and enteric inflammation; 3) FXR impedes aberrant activation of some cancer-related pathways; and 4) FXR downregulates a number of oncogenes while upregulating some tumor suppressor genes. Restoring FXR functions via its agonists provides a therapeutic approach for patients with liver cancer and CRC. However, an in-depth understanding of the species-specific pharmacological effects is a prerequisite for assessing the clinical safety and efficacy of FXR agonists in human cancer treatment.

Alcohol triggered bile acid disequilibrium by suppressing BSEP to sustain hepatocellular carcinoma progression

Bile acids (BAs), the most important components of bile, attribute predominately to maintain metabolic homeostasis. In hepatocellular carcinoma (HCC) patients, the BAs homeostasis was seriously disturbed, especially in those patients with alcohol-intake history. However, whether alcohol consumption could promote HCC progression via influencing BAs homeostasis and the precise mechanism underlying are still unclear. In our study, by collecting HCC specimens from both alcohol-drinkers (n = 15) and non-alcohol drinkers (n = 22), we found that compared to non-alcohol intake HCC patients, BAs homeostasis was disturbed in HCC patients who drank alcohol. Furthermore, ethanol treatment was also found to promote HCC progression by markedly activating oncogenes (RAS, MYC, MET, and HER2), while remarkably suppressing tumor suppressor genes (BRCA2 and APC). We evaluated 14 key functional genes that maintain the homeostasis of BAs and found that either in alcohol-intake HCC patients (n = 15), or in ethanol-treated mice, BSEP, rate-limiting transporter governing excreting BAs from liver into bile duct, was remarkably decreased when exposed to alcohol. Moreover, by screening for changes in the epigenetic landscape of liver cancer cells exposed to alcohol, we strikingly found that histone methyltransferases (RBBP-5, Suv39h1, ASH2L, and SET7/9) were increased, and KMT3B, KMT4, and KMT7 gene expression was also elevated, while histone demethyltransferases (JARID1a, JARID1b, JARID1c) were decreased. In summary, we found that alcohol could trigger BAs disequilibrium to initiate and promote HCC progression. Our study provided a novel and supplementary mechanism to determine the important role of alcohol-intake in HCC development regarding from the perspective of BAs homeostasis.

D-galactose induced dysfunction in mice hippocampus and the possible antioxidant and neuromodulatory effects of selenium

Aging is an ultimate reality that everyone has to face. D-galactose (D-gal) has been used extensively to develop aging model. Trace elements such as selenium (Se) have been used as a potential antioxidant for neuro-protection. The present work aims to develop therapeutic agents such as Se for the treatment of aging-induced neurological ailments such as anxiety, depression, and memory impairment. For this purpose, mice were treated with D-gal at a dose of 300 mg/ml/kg and various doses of Se (0.175 and 0.35mg/ml/kg) for 28 days. Behavioral tests were monitored after treatment days. After the behavioral assessment, mice were decapitated and their brains were collected. Hippocampi were removed from the brain for biochemical, neurochemical, and histopathological analysis. The present findings of behavioral analysis showed that D-gal-induced anxiety- and depression-like symptoms were inhibited by both doses of Se. D-gal-induced memory alteration was also prevented by repeated doses of Se (0.175 and 0.35mg/ml/kg). Biochemical analysis showed that D-gal-induced increase of oxidative stress and inflammatory markers and decrease of antioxidant enzymes and total protein contents in the hippocampus were prevented by Se administration. An increase in the activity of acetylcholinesterase was also diminished by Se. The neurochemical assessment showed that D-gal-induced increased serotonin metabolism and decreased acetylcholine levels in the hippocampus were restored by repeated treatment of Se. Histopathological estimations also exhibited; normalization of D-gal induced neurodegenerative changes. It is concluded that D-gal-induced dysfunction in mice hippocampus caused anxiety, depression, memory impairment, oxidative stress, neuro-inflammation, and histological alterations that were mitigated by Se via its antioxidant potential, anti-inflammatory property, and modulating capability of serotonergic and cholinergic functions.

Management of Dietary Habits and Diarrhea in Fap Individuals: A Mediterranean Low-Inflammatory Dietary Intervention

Background: A total colectomy and a frequent life-long endoscopic surveillance are guaranteed to patients with Familial Adenomatous Polyposis (FAP) to reduce their risk of duodenal and rectal stump cancers. However, after surgery, individuals with FAP suffer from an increased number of diarrheal discharges that force them to dietary restrictions. A non-randomized pilot study was conducted to assess whether a three-month low-inflammatory Mediterranean dietary intervention reduces gastro-intestinal markers of inflammation in FAP individuals. The aim of the present work is to evaluate the participant’s adherence to the proposed dietary recommendations and the change in their number of diarrheal discharges. Methods: 26 FAP individuals aged >18 years, who underwent a total colectomy with ileo-rectal anastomosis and were involved in the surveillance program at the Fondazione IRCCS Istituto Nazionale Tumori of Milan, were included in the present analysis. Results: FAP individuals significantly reduced the Not recommended foods (p-value: 0.002) and increased the consumption of the Recommended ones (p-value: 0.075). The adherence to the proposed dietary recommendations was accompanied by a significant decrease in the number of diarrheal discharges (p-value: 0.008). Conclusions: This study suggests that adhering to a low-inflammatory Mediterranean diet has a potential protective effect on the number of diarrheal discharges in FAP individuals.

Dietary fat, bile acid metabolism and colorectal cancer

Colorectal cancer (CRC) risk is predominantly driven by environmental factors, in particular diet. A high intake of dietary fat has been implicated as a risk factor inducing the formation of pre-neoplastic lesions (e.g., adenomatous polyps) and/or exacerbating colonic tumorigenesis. Recent data attributed the tumor-promoting activity of high-fat diets to their effects on gut microbiota composition and metabolism, in particular with regard to bile acids. Bile acids are synthesized in the liver in response to dietary fat and facilitate lipid absorption in the small intestine. The majority of bile acids is re-absorbed during small intestinal transit and subjected to enterohepatic circulation. Bile acids entering the colon undergo complex biotransformation performed by gut bacteria, resulting in secondary bile acids that show tumor-promoting activity. Excessive dietary fat leads to high levels of secondary bile acids in feces and primes the gut microbiota to bile acid metabolism. This promotes an altered overall bile acid pool, which activates or restricts intestinal and hepatic cross-signaling of the bile acid receptor, farnesoid X receptor (FXR). Recent studies provided evidence that FXR is a main regulator of bile acid-mediated effects on intestinal tumorigenesis integrating dietary, microbial and genetic risk factors for CRC. Selective FXR agonist or antagonist activity by specific bile acids depends on additional factors (e.g., bile acid concentration, composition of bile acid pool, genetic instability of cells) and, thus, may differ in healthy and tumorigenic conditions in the intestine. In conclusion, fat-mediated alterations of the gut microbiota link bile acid metabolism to CRC risk and colonic tumorigenesis, exemplifying how gut microbial co-metabolism affects colon health.

n-6 High Fat Diet Induces Gut Microbiome Dysbiosis and Colonic Inflammation

Background: Concerns are emerging that a high-fat diet rich in n-6 PUFA (n-6HFD) may alter gut microbiome and increase the risk of intestinal disorders. Research is needed to model the relationships between consumption of an n-6HFD starting at weaning and development of gut dysbiosis and colonic inflammation in adulthood. We used a C57BL/6J mouse model to compare the effects of exposure to a typical American Western diet (WD) providing 58.4%, 27.8%, and 13.7% energy (%E) from carbohydrates, fat, and protein, respectively, with those of an isocaloric and isoproteic soybean oil-rich n-6HFD providing 50%E and 35.9%E from total fat and carbohydrates, respectively on gut inflammation and microbiome profile. Methods: At weaning, male offspring were assigned to either the WD or n-6HFD through 10-16 weeks of age. The WD included fat exclusively from palm oil whereas the n-6HFD contained fat exclusively from soybean oil. We recorded changes in body weight, cyclooxygenase-2 (COX-2) expression, colon histopathology, and gut microbiome profile. Results: Compared to the WD, the n-6HFD increased plasma levels of n-6 fatty acids; colonic expression of COX-2; and the number of colonic inflammatory and hyperplastic lesions. At 16 weeks of age, the n-6HFD caused a marked reduction in the gut presence of Firmicutes, Clostridia, and Lachnospiraceae, and induced growth of Bacteroidetes and Deferribacteraceae. At the species level, the n-6HFD sustains the gut growth of proinflammatory Mucispirillum schaedleri and Lactobacillus murinus. Conclusions: An n-6HFD consumed from weaning to adulthood induces a shift in gut bacterial profile associated with colonic inflammation.

Fatty acid-binding protein 3 regulates differentiation of IgM-producing plasma cells

Plasma cells (PCs), which aim to protect host health, produce various subsets of immunoglobulin (Ig) in response to extracellular pathogens. Blimp-1 (encoded by Prdm1)-a protein that is highly expressed by PCs-is important for PC functions, including the generation of Igs. Fatty acid-binding protein 3 (FABP3) is a carrier protein of polyunsaturated fatty acids (PUFAs) and participates in multiple cellular functions. Although the functions of FABP3 in neurons and cardiac myocytes are well-noted, their roles in immune cells remain to be fully elucidated. In this study, we demonstrate that FABP3 is expressed in activated B cells and that FABP3 promotes PC development and IgM secretion. Moreover, we provide the first evidence that FABP3 is necessary for Blimp-1 expression, by regulating the histone modification of its promoter region. Taken together, our findings reveal that FABP3 acts as a positive regulator of B-cell activation by controlling histone acetylation of the Blimp-1 gene, thereby playing a role in host defense against pathogens.

Diet-Associated Inflammation Modulates Inflammation and WNT Signaling in the Rectal Mucosa, and the Response to Supplementation with Dietary Fiber

Inflammation drives colorectal cancer development, and colorectal cancer risk is influenced by dietary factors, including dietary fiber. Hyperactive WNT signaling occurs in colorectal cancer and may regulate inflammation. This study investigated (i) relationships between the inflammatory potential of diet, assessed using the Energy-adjusted Dietary Inflammatory Index (E-DII), and markers of WNT signaling, and (ii) whether DII status modulated the response to supplementation with two types of dietary fiber. Seventy-five healthy participants were supplemented with resistant starch and/or polydextrose (PD) or placebo for 50 days. Rectal biopsies were collected before and after intervention and used to assess WNT pathway gene expression and crypt cell proliferation. E-DII scores were calculated from food frequency questionnaire data. High-sensitivity C-reactive protein (hsCRP) and fecal calprotectin concentrations were quantified. hsCRP concentration was significantly greater in participants with higher E-DII scores [least square means (LSM) 4.7 vs. 2.4 mg/L, P = 0.03]. Baseline E-DII score correlated with FOSL1 (β = 0.503, P = 0.003) and WNT11 (β = 0.472, P = 0.006) expression, after adjusting for age, gender, body mass index, endoscopy procedure, and smoking status. WNT11 expression was more than 2-fold greater in individuals with higher E-DII scores (LSM 0.131 vs. 0.059, P = 0.002). Baseline E-DII modulated the effects of PD supplementation on FOSL1 expression (P = 0.04). More proinflammatory diets were associated with altered WNT signaling and appeared to modulate the effects of PD supplementation on expression of FOSL1 This is the first study to investigate relationships between the E-DII and molecular markers of WNT signaling in rectal tissue of healthy individuals.Prevention Relevance: Our finding that more inflammatory dietary components may impact large bowel health through effects on a well-recognized pathway involved in cancer development will strengthen the evidence base for dietary advice to help prevent bowel cancer.

A Villin-Driven Fxr Transgene Modulates Enterohepatic Bile Acid Homeostasis and Response to an n-6-Enriched High-Fat Diet

A diet high in n-6 polyunsaturated fatty acids (PUFAs) may contribute to inflammation and tissue damage associated with obesity and pathologies of the colon and liver. One contributing factor may be dysregulation by n-6 fatty acids of enterohepatic bile acid (BA) metabolism. The farnesoid X receptor (FXR) is a nuclear receptor that regulates BA homeostasis in the liver and intestine. This study aims to compare the effects on FXR regulation and BA metabolism of a palm oil-based diet providing 28% energy (28%E) from fat and low n-6 linoleic acid (LA, 2.5%E) (CNTL) with those of a soybean oil-based diet providing 50%E from fat and high (28%E) in LA (n-6HFD). Wild-type (WT) littermates and a transgenic mouse line overexpressing the Fxrα1 isoform under the control of the intestine-specific Villin promoter (Fxrα1^TG) were fed the CNTL or n-6HFD starting at weaning through 16 weeks of age. Compared to the CNTL diet, the n-6HFD supports higher weight gain in both WT and Fxrα^TG littermates; increases the expression of Fxrα1/2, and peroxisome proliferator-activated receptor-γ1 (Pparγ1) in the small intestine, Fxrα1/2 in the colon, and cytochrome P4507A1 (Cyp7a1) and small heterodimer protein (Shp) in the liver; and augments the levels of total BA in the liver, and primary chenodeoxycholic (CDCA), cholic (CA), and β-muricholic (βMCA) acid in the cecum. Intestinal overexpression of the Fxra1^TG augments expression of Shp and ileal bile acid-binding protein (Ibabp) in the small intestine and Ibabp in the proximal colon. Conversely, it antagonizes n-6HFD-dependent accumulation of intestinal and hepatic CDCA and CA; hepatic levels of Cyp7a1; and expression of Pparγ in the small intestine. We conclude that intestinal Fxrα1 overexpression represses hepatic de novo BA synthesis and protects against n-6HFD-induced accumulation of human-specific primary bile acids in the cecum.

Dietary Choices Modulate Colorectal Cancer Stem Cells: A Role of FXR Nuclear Receptor

Intra- and inter-tumor heterogeneity (TMH) among colorectal cancer patients is considered as major hurdles to develop precise, potent, and personalized cancer therapeutics. The discernible factors that contribute to the existence of TMH and associated problems are suggested as genetic, molecular, epigenetic, and environmental pressures including shifts in trend from high-fiber diet to high-fat/processed sugar diet. In essence, components of high fat/processed sugar diet potentiate metabolic re-programing of inherent cellular heterogeneity of cancer stem cells (CSCs) by genetic and epigenetic pathways intersected by the farnesoid X receptor (FXR) nuclear receptor. Therefore, choices of dietary components shape up protumor or antitumor microenvironment by the modulation of FXR regulated transcriptional and epigenetic events in CSCs. In this article, we highlight the major understanding emanated from preclinical and clinical studies that indicate the potential contribution of high fiber/saturated sugar diet toward carcinogenesis of colorectal cancer.

Dietary Fat and Cancer-Which Is Good, Which Is Bad, and the Body of Evidence

A high-fat diet (HFD) induces changes in gut microbiota leading to activation of pro-inflammatory pathways, and obesity, as a consequence of overnutrition, exacerbates inflammation, a known risk factor not only for cancer. However, experimental data showed that the composition of dietary fat has a greater impact on the pathogenesis of cancer than the total fat content in isocaloric diets. Similarly, human studies did not prove that a decrease in total fat intake is an effective strategy to combat cancer. Saturated fat has long been considered as harmful, but the current consensus is that moderate intake of saturated fatty acids (SFAs), including palmitic acid (PA), does not pose a health risk within a balanced diet. In regard to monounsaturated fat, plant sources are recommended. The consumption of plant monounsaturated fatty acids (MUFAs), particularly from olive oil, has been associated with lower cancer risk. Similarly, the replacement of animal MUFAs with plant MUFAs decreased cancer mortality. The impact of polyunsaturated fatty acids (PUFAs) on cancer risk depends on the ratio between ω-6 and ω-3 PUFAs. In vivo data showed stimulatory effects of ω-6 PUFAs on tumour growth while ω-3 PUFAs were protective, but the results of human studies were not as promising as indicated in preclinical reports. As for trans FAs (TFAs), experimental data mostly showed opposite effects of industrially produced and natural TFAs, with the latter being protective against cancer progression, but human data are mixed, and no clear conclusion can be made. Further studies are warranted to establish the role of FAs in the control of cell growth in order to find an effective strategy for cancer prevention/treatment.

Flaxseed oil supplementation improves intestinal function and immunity, associated with altered intestinal microbiome and fatty acid profile in pigs with intrauterine growth retardation

Flaxseed oil (FO), enriched in n-3 polyunsaturated fatty acids (PUFAs), is an important oil source for intestinal development and health. We aimed to study the different effects of FO versus soybean oil (SO) on growth, intestinal health and immune function of neonates with intrauterine growth retardation (IUGR) using a weaned piglet model. Forty pairs of male IUGR and normal birth weight piglets, weaned at 21 ± 1 d, were fed diets containing either 4% FO or SO for 3 weeks consecutively. Growth performance, nutrient digestibility and intestinal function parameters, immunology and microbiota composition were determined. IUGR led to a poor growth rate, nutrient digestibility and abnormal immunology variables, whereas feeding FO diet improved systemic and gut immunity, as indicated by increased plasma concentration of immunoglobulin G and decreased CD3+CD8+ T lymphocytes, and down-regulated intestinal expression of genes (MyD88, NF-κB, TNF-α, IL-10). Although IUGR tended to decrease villous height, feeding FO diet tended to increase the villi-crypt ratio and up-regulated expressions of tight junction genes (Claudin-1 and ZO-1), together with increased mucosa contents of n-3 PUFAs and a lower Σn-6/Σn-3 ratio. Besides, FO diet decreased the abundance of pathogenic bacteria Spirochaetes, and increased phylum Actinobacteria, and genera Blautia and Bifidobacterium in colonic digesta. Our findings indicate that IUGR impairs growth rate, nutrient digestibility, and partly immunology variables, whereas feeding FO-supplemented diet could improve intestinal function and immunity of both IUGR and NBW pigs, associated with the altered gut microbiome and mucosal fatty acid profile.

The interplay between dietary factors, gut microbiome and colorectal cancer: a new era of colorectal cancer prevention

Colorectal cancer is the third most common cancer in the world and its incidence is on the rise. Dietary intervention has emerged as an attractive strategy to curtail its occurrence and progression. Diet is known to influence the gut microbiome, as dietary factors and gut bacteria can act in concert to cause or protect from colorectal cancer. Several studies have presented evidence for such interactions and have pointed out the different ways by which the diet and gut microbiome can be altered to produce beneficial effects. This review article aims to summarize the interrelationship between diet, gut flora and colorectal cancer so that a better preventive approach can be applied.

Bone Benefits of Fish Oil Supplementation Depend on its EPA and DHA Content

The preventive effect of high-dose (9%) regular-fish oil (FO) against bone loss during aging has been demonstrated, but the effects of a low-dose (1%–4%) of a highly purified concentrated FO (CFO) has not been elucidated. The aim of this study was to determine the dose-dependent effect of a CFO against bone loss in C57BL/6 female mice during aging. Twelve-month old mice were fed with 1% and 4% CFO and 4% safflower oil (SFO) diets, including a group with a 4% regular-FO diet and a group with a lab chow diet for 12 months. Bone mineral density (BMD) was analyzed by dual-energy x-ray absorptiometry (DXA) before and after the dietary intervention. At the end of dietary intervention, bone resorption markers in serum and inflammatory markers in bone marrow and splenocytes and inflammatory signaling pathways in the bone marrow were analyzed. As compared to the 4% SFO control, 4% CFO maintained higher BMD during aging, while 1% CFO offered only a mild benefit. However, the 1% CFO fed group exhibited slightly better BMD than the 4% regular-FO fed group. BMD loss protection by CFO was accompanied by reduced levels of the bone resorption marker, TRAP, and the osteoclast-stimulating-factor, RANKL, without affecting the decoy-receptor of RANKL, osteoprotegerin (OPG). Further, CFO supplementation was associated with an increase in the production of IL-10, IL-12, and IFN-γ and a decrease in the production of TNF-α and IL-6, and the activation of NF-κB, p38 MAPK, and JNK signaling pathways. In conclusion, the supplementation of 4% CFO is very efficient in maintaining BMD during aging, whereas 1% CFO is only mildly beneficial. CFO supplementation starting at middle age may maintain better bone health during aging.

Oxysterols and Gastrointestinal Cancers Around the Clock

This review focuses on the role of oxidized sterols in three major gastrointestinal cancers (hepatocellular carcinoma, pancreatic, and colon cancer) and how the circadian clock affects the carcinogenesis by regulating the lipid metabolism and beyond. While each field of research (cancer, oxysterols, and circadian clock) is well-studied within their specialty, little is known about the intertwining mechanisms and how these influence the disease etiology in each cancer type. Oxysterols are involved in pathology of these cancers, but final conclusions about their protective or damaging effects are elusive, since the effect depends on the type of oxysterol, concentration, and the cell type. Oxysterol concentrations, the expression of key regulators liver X receptors (LXR), farnesoid X receptor (FXR), and oxysterol-binding proteins (OSBP) family are modulated in tumors and plasma of cancer patients, exposing these proteins and selected oxysterols as new potential biomarkers and drug targets. Evidence about how cholesterol/oxysterol pathways are intertwined with circadian clock is building. Identified key contact points are different forms of retinoic acid receptor related orphan receptors (ROR) and LXRs. RORs and LXRs are both regulated by sterols/oxysterols and the circadian clock and in return also regulate the same pathways, representing a complex interplay between sterol metabolism and the clock. With this in mind, in addition to classical therapies to modulate cholesterol in gastrointestinal cancers, such as the statin therapy, the time is ripe also for therapies where time and duration of the drug application is taken as an important factor for successful therapies. The final goal is the personalized approach with chronotherapy for disease management and treatment in order to increase the positive drug effects.