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Frontiers in Immunology 2023The gut is colonized by many commensal microorganisms, and the diversity and metabolic patterns of microorganisms profoundly influence the intestinal health. These... (Review)
Review
The gut is colonized by many commensal microorganisms, and the diversity and metabolic patterns of microorganisms profoundly influence the intestinal health. These microbial imbalances can lead to disorders such as inflammatory bowel disease (IBD). Microorganisms produce byproducts that act as signaling molecules, triggering the immune system in the gut mucosa and controlling inflammation. For example, metabolites like short-chain fatty acids (SCFA) and secondary bile acids can release inflammatory-mediated signals by binding to specific receptors. These metabolites indirectly affect host health and intestinal immunity by interacting with the intestinal epithelial and mucosal immune cells. Moreover, Tryptophan-derived metabolites also play a role in governing the immune response by binding to aromatic hydrocarbon receptors (AHR) located on the intestinal mucosa, enhancing the intestinal epithelial barrier. Dietary-derived indoles, which are synthetic precursors of AHR ligands, work together with SCFA and secondary bile acids to reduce stress on the intestinal epithelium and regulate inflammation. This review highlights the interaction between gut microbial metabolites and the intestinal immune system, as well as the crosstalk of dietary fiber intake in improving the host microbial metabolism and its beneficial effects on the organism.
Topics: Humans; Intestinal Mucosa; Inflammatory Bowel Diseases; Inflammation; Bile Acids and Salts
PubMed: 37876938
DOI: 10.3389/fimmu.2023.1277102 -
Gastroenterology Jun 2024Nonresponsive celiac disease (CeD) is relatively common. It is generally attributed to persistent gluten exposure and resolves after correction of diet errors. However,... (Review)
Review
Nonresponsive celiac disease (CeD) is relatively common. It is generally attributed to persistent gluten exposure and resolves after correction of diet errors. However, other complications of CeD and disorders clinically mimicking CeD need to be excluded. Novel therapies are being evaluated to facilitate mucosal recovery, which might benefit patients with nonresponsive CeD. Refractory CeD (RCeD) is rare and is divided into 2 types. The etiology of type I RCeD is unclear. A switch to gluten-independent autoimmunity is suspected in some patients. In contrast, type II RCeD represents a low-grade intraepithelial lymphoma. Type I RCeD remains a diagnosis of exclusion, requiring ruling out gluten intake and other nonmalignant causes of villous atrophy. Diagnosis of type II RCeD relies on the demonstration of a clonal population of neoplastic intraepithelial lymphocytes with an atypical immunophenotype. Type I RCeD and type II RCeD generally respond to open-capsule budesonide, but the latter has a dismal prognosis due to severe malnutrition and frequent progression to enteropathy-associated T-cell lymphoma; more efficient therapy is needed.
Topics: Celiac Disease; Humans; Diet, Gluten-Free; Intestinal Mucosa; Glutens; Treatment Outcome; Budesonide
PubMed: 38556189
DOI: 10.1053/j.gastro.2024.02.048 -
Microbial Biotechnology Oct 2023It has been reported that Akkermansia muciniphila improves host metabolism and reduces inflammation; however, its potential effects on bile acid metabolism and metabolic...
It has been reported that Akkermansia muciniphila improves host metabolism and reduces inflammation; however, its potential effects on bile acid metabolism and metabolic patterns in metabolic-associated fatty liver disease (MAFLD) are unknown. In this study, we have analysed C57BL/6 mice under three feeding conditions: (i) a low-fat diet group (LP), (ii) a high-fat diet group (HP) and (iii) a high-fat diet group supplemented with A. muciniphila (HA). The results found that A. muciniphila administration relieved weight gain, hepatic steatosis and liver injury induced by the high-fat diet. A. muciniphila altered the gut microbiota with a decrease in Alistipes, Lactobacilli, Tyzzerella, Butyricimonas and Blautia, and an enrichment of Ruminiclostridium, Osclibacter, Allobaculum, Anaeroplasma and Rikenella. The gut microbiota changes correlated significantly with bile acids. Meanwhile, A. muciniphila also improved glucose tolerance, gut barriers and adipokines dysbiosis. Akkermansia muciniphila regulated the intestinal FXR-FGF15 axis and reshaped the construction of bile acids, with reduced secondary bile acids in the caecum and liver, including DCA and LCA. These findings provide new insights into the relationships between probiotics, microflora and metabolic disorders, highlighting the potential role of A. muciniphila in the management of MAFLD.
Topics: Animals; Mice; Diet, High-Fat; Gastrointestinal Microbiome; Bile Acids and Salts; Mice, Inbred C57BL; Verrucomicrobia; Metabolic Diseases; Liver Diseases
PubMed: 37377410
DOI: 10.1111/1751-7915.14293 -
Advances in Nutrition (Bethesda, Md.) Sep 2023Cardiovascular disease (CVD) is the leading cause of death globally. Habitual consumption of tree nuts and peanuts is associated with cardioprotective benefits.... (Meta-Analysis)
Meta-Analysis Review
Cardiovascular disease (CVD) is the leading cause of death globally. Habitual consumption of tree nuts and peanuts is associated with cardioprotective benefits. Food-based dietary guidelines globally recommend nuts as a key component of a healthy diet. This systematic review and meta-analysis were conducted to examine the relationship between tree nut and peanut consumption and risk factors for CVD in randomized controlled trials (RCTs) (PROSPERO: CRD42022309156). MEDLINE, PubMed, CINAHL, and Cochrane Central databases were searched up to 26 September, 2021. All RCT studies that assessed the effects of tree nut or peanut consumption of any dose on CVD risk factors were included. Review Manager software was used to conduct a random effect meta-analysis for CVD outcomes from RCTs. Forest plots were generated for each outcome, between-study heterogeneity was estimated using the I test statistic and funnel plots and Egger's test for outcomes with ≥10 strata. The quality assessment used the Health Canada Quality Appraisal Tool, and the certainty of the evidence was assessed using grading of recommendations assessment, development, and evaluation (GRADE). A total of 153 articles describing 139 studies (81 parallel design and 58 cross-over design) were included in the systematic review, with 129 studies in the meta-analysis. The meta-analysis showed a significant decrease for low-density lipoprotein (LDL) cholesterol, total cholesterol (TC), triglycerides (TG), TC:high-density lipoprotein (HDL) cholesterol, LDL cholesterol:HDL cholesterol, and apolipoprotein B (apoB) following nut consumption. However, the quality of evidence was "low" for only 18 intervention studies. The certainty of the body of evidence for TC:HDL cholesterol, LDL cholesterol:HDL cholesterol, and apoB were "moderate" because of inconsistency, for TG were "low," and for LDL cholesterol and TC were "very low" because of inconsistency and the likelihood of publication bias. The findings of this review provide evidence of a combined effect of tree nuts and peanuts on a range of biomarkers to create an overall CVD risk reduction.
Topics: Humans; Cardiovascular Diseases; Nuts; Arachis; Cholesterol, LDL; Cholesterol, HDL; Randomized Controlled Trials as Topic; Cholesterol; Triglycerides; Apolipoproteins B
PubMed: 37149262
DOI: 10.1016/j.advnut.2023.05.004 -
Nutrients Oct 2023Cholecystectomy (CCE) is a standard clinical treatment for conditions like gallstones and cholecystitis. However, its link to post-CCE syndrome, colorectal cancer, and...
Cholecystectomy (CCE) is a standard clinical treatment for conditions like gallstones and cholecystitis. However, its link to post-CCE syndrome, colorectal cancer, and nonalcoholic fatty liver disease has raised concerns. Additionally, studies have demonstrated the disruptive effects of CCE on gut microbiota homeostasis and bile acid (BA) metabolism. Considering the role of gut microbiota in regulating host metabolic and immune pathways, the use of dietary and probiotic intervention strategies to maintain a stable gut ecosystem after CCE could potentially reduce associated disease risks. Inter-study variations have made it challenging to identify consistent gut microbiota patterns after CCE, a prerequisite for targeted interventions. In this study, we first meta-analyzed 218 raw 16S rRNA gene sequencing datasets to determine consistent patterns of structural and functional changes in the gut microbiota after CCE. Our results revealed significant alterations in the gut microbiota's structure and function due to CCE. Furthermore, we identified characteristic gut microbiota changes associated with CCE by constructing a random model classifier. In the validation cohort, this classifier achieved an area under the receiver operating characteristic curve (AUC) of 0.713 and 0.683 when distinguishing between the microbiota of the CCE and healthy groups at the family and genus levels, respectively. Further, fecal metabolomics analysis demonstrated that CCE also substantially modified the metabolic profile, including decreased fecal short-chain fatty acid levels and disrupted BA metabolism. Importantly, dietary patterns, particularly excessive fat and total energy intake, influenced gut microbiota and metabolic profile changes post-CCE. These dietary habits were associated with further enrichment of the microbiota related to BA metabolism and increased levels of intestinal inflammation after CCE. In conclusion, our study identified specific alterations in gut microbiota homeostasis and metabolic profiles associated with CCE. It also revealed a potential link between dietary patterns and gut microbiota changes following CCE. Our study provides a theoretical basis for modulating gut microbiota homeostasis after CCE using long-term dietary strategies and probiotic interventions.
Topics: Humans; Cross-Sectional Studies; Gastrointestinal Microbiome; RNA, Ribosomal, 16S; Ecosystem; Metabolome; Homeostasis; Cholecystectomy; Bile Acids and Salts
PubMed: 37892474
DOI: 10.3390/nu15204399 -
Nutrients Oct 2023Melanoma, a prevalent and lethal form of skin cancer, remains a formidable challenge in terms of prevention and treatment. While significant progress has been made in... (Review)
Review
Melanoma, a prevalent and lethal form of skin cancer, remains a formidable challenge in terms of prevention and treatment. While significant progress has been made in understanding its pathogenesis and treatment, the quest for effective prevention strategies and therapeutic approaches remains ongoing. Considering the increased advancements in understanding the dynamic interplay between nutrients and melanoma, we aim to offer a refreshed perspective on nutrient-based approaches for melanoma prevention and adjunctive therapy. In contrast to other studies, we have innovatively provided a detailed exposition of the nutrients' influences on melanoma prognosis and treatment. This review firstly examines various nutrients, including antioxidants (namely vitamins A, D, C, and E; selenium; and caffeine), polyunsaturated fatty acids, and flavonoids, for their effects and underlying mechanisms in reducing melanoma risk. Among these nutrients, caffeine shows the most promising potential, as it is supported by multiple cohort studies for its protective effect against melanoma. In contrast, there is a certain degree of inconsistency in the research of other nutrients, possibly due to inherent differences between animal studies and epidemiological research, as well as variations in the definition of nutrient intake. To comprehensively investigate the impact of nutrients on melanoma progression and therapeutic approaches, the following sections will explore how nutrients influence immune responses and other physiological processes. While there is robust support from cell and animal studies regarding the immunomodulatory attributes of vitamins D and zinc, the anti-angiogenic potential of polyphenols, and the cell growth-inhibitory effects of flavonoids, the limited availability of human-based research substantially constrains their practical relevance in clinical contexts. As for utilizing nutrients in adjuvant melanoma treatments, multiple approaches have garnered clinical research support, including the utilization of vitamin D to decrease the postoperative recurrence rates among melanoma patients and the adoption of a high-fiber diet to enhance the effectiveness of immunotherapy. In general, the effects of most nutrients on reducing the risk of melanoma are not entirely clear. However, several nutrients, including vitamin D and dietary fiber, have demonstrated their potential to improve the melanoma prognosis and enhance the treatment outcomes, making them particularly deserving of clinical attention. A personalized and interdisciplinary approach, involving dermatologists, oncologists, nutritionists, and researchers, holds the promise of optimizing melanoma treatment strategies.
Topics: Humans; Caffeine; Vitamins; Melanoma; Vitamin D; Vitamin A; Flavonoids; Diet
PubMed: 37892558
DOI: 10.3390/nu15204483 -
The Journal of Clinical Endocrinology... Nov 2023Childhood overweight has been linked to earlier development of adrenarche and puberty, but it remains unknown if lifestyle interventions influence sexual maturation in...
CONTEXT
Childhood overweight has been linked to earlier development of adrenarche and puberty, but it remains unknown if lifestyle interventions influence sexual maturation in general populations.
OBJECTIVE
To investigate if a 2-year lifestyle intervention influences circulating androgen concentrations and sexual maturation in a general population of children.
METHODS
We conducted a 2-year physical activity and dietary intervention study in which 421 prepubertal and mostly normal-weight 6- to 9-year-old children were allocated either to a lifestyle intervention group (119 girls, 132 boys) or a control group (84 girls, 86 boys). The main outcome measures were serum dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), androstenedione (A4), and testosterone concentrations, and clinical adrenarchal and pubertal signs.
RESULTS
The intervention and control groups had no differences in body size and composition, clinical signs of androgen action, and serum androgens at baseline. The intervention attenuated the increase of DHEA (P = .032), DHEAS (P = .001), A4 (P = .003), and testosterone (P = .007) and delayed pubarche (P = .038) in boys but it only attenuated the increase of DHEA (P = .013) and DHEAS (P = .003) in girls. These effects of lifestyle intervention on androgens and the development of pubarche were independent of changes in body size and composition, but the effects of intervention on androgens were partly explained by changes in fasting serum insulin.
CONCLUSION
A combined physical activity and dietary intervention attenuates the increase of serum androgen concentrations and sexual maturation in a general population of prepubertal and mostly normal-weight children, independently of changes in body size and composition.
Topics: Child; Female; Humans; Male; Adrenarche; Androgens; Androstenedione; Dehydroepiandrosterone; Dehydroepiandrosterone Sulfate; Puberty; Testosterone; Exercise; Diet, Healthy
PubMed: 37329220
DOI: 10.1210/clinem/dgad367 -
Nutrients Aug 2023Maternal vitamin D deficiency, which is highly prevalent in pregnant women in Europe, is linked to adverse health effects for both the mother and child. The objective...
Maternal vitamin D deficiency, which is highly prevalent in pregnant women in Europe, is linked to adverse health effects for both the mother and child. The objective was to assess vitamin D status in pregnant women by evaluating their dietary and supplemental vitamin D intake, serum vitamin D levels, parathyroid hormone levels, and lifestyle factors. This cross-sectional study, with a total of 735 participants (145 pregnant and 590 up to the seventh day postpartum), took place in Latvia. Blood samples, a food frequency questionnaire, and medical documentation were used for data collection. The median serum vitamin D concentration was 34.0 ng/mL, with pregnant women having higher levels (42.9 ng/mL) than postpartum women (31.8 ng/mL). There was no association between vitamin D serum concentration and dietary intake of vitamin D ( > 0.05), whereas there was a significant correlation with use of vitamin D supplements (r = 0.41; < 0.001 in pregnant women and r = 0.35; < 0.001 in postpartum women). This study demonstrated that a minority of pregnant women (21.9%) had optimal serum vitamin D concentration (>45 ng/mL), and diet had no significant impact on vitamin D levels. Thus, our proposed recommendation for vitamin D intake during pregnancy was 63 mcg (2500 IU) year-round for optimal levels in pregnant women in Northeastern Europe.
Topics: Child; Humans; Female; Pregnancy; Cross-Sectional Studies; Vitamin D; Nutritional Status; Vitamin D Deficiency; Postpartum Period; Dietary Supplements; Vitamins; Pregnant Women
PubMed: 37571431
DOI: 10.3390/nu15153493 -
Clinical Nutrition (Edinburgh, Scotland) Aug 2023Diet may play an essential role in the aetiology of bladder cancer (BC). Vitamin D is involved in various biological functions which have the potential to prevent BC... (Meta-Analysis)
Meta-Analysis
BACKGROUND & AIMS
Diet may play an essential role in the aetiology of bladder cancer (BC). Vitamin D is involved in various biological functions which have the potential to prevent BC development. Besides, vitamin D also influences the uptake of calcium and phosphorus, thereby possibly indirectly influencing the risk of BC. The aim of the present study was to investigate the relation between vitamin D intake and BC risk.
METHODS
Individual dietary data were pooled from ten cohort studies. Food item intake was converted to daily intakes of vitamin D, calcium and phosphorus. Pooled multivariate hazard ratios (HRs), with corresponding 95% confidence intervals (CIs) were obtained using Cox-regression models. Analyses were adjusted for gender, age and smoking status (Model 1), and additionally for the food groups fruit, vegetables and meat (Model 2). Dose-response relationships (Model 1) were examined using a nonparametric test for trend.
RESULTS
In total, 1994 cases and 518,002 non-cases were included in the analyses. The present study showed no significant associations between individual nutrient intake and BC risk. A significant decreased BC risk was observed for high vitamin D intake with moderate calcium and low phosphorus intake (Model 2: HR: 0.77, 95% CI: 0.59-1.00). No significant dose-response analyses were observed.
CONCLUSION
The present study showed a decreased BC risk for high dietary vitamin D intake in combination with low calcium intake and moderate phosphorus intake. The study highlights the importance of examining the effect of a nutrient in combination with complementary nutrients for risk assessment. Future research should focus on nutrients in a wider context and in nutritional patterns.
Topics: Humans; Calcium; Prospective Studies; Phosphorus, Dietary; Diet; Vitamin D; Vitamins; Calcium, Dietary; Urinary Bladder Neoplasms; Cohort Studies; Phosphorus; Risk Factors
PubMed: 37321901
DOI: 10.1016/j.clnu.2023.05.010 -
International Journal of Molecular... Aug 2023Colorectal cancer (CRC) is one of the leading causes of mortality for cancer in industrialized countries. The link between diet and CRC is well-known, and presumably CRC... (Review)
Review
Colorectal cancer (CRC) is one of the leading causes of mortality for cancer in industrialized countries. The link between diet and CRC is well-known, and presumably CRC is the type of cancer which is most influenced by dietary habits. In Western countries, an inadequate dietary intake of fibers is endemic, and this could be a driving factor in the increase of CRC incidence. Indeed, several epidemiologic studies have elucidated an inverse relationship between daily fiber intake and risk of CRC. Long-term prognosis in CRC survivors is also dependent on dietary fibers. Several pathogenetic mechanisms may be hypothesized. Fibers may interfere with the metabolism of bile acids, which may promote colon carcinogenesis. Further, fibers are often contained in vegetables which, in turn, contain large amounts of antioxidant agents like resveratrol, polyphenols, or phytoestrogens. Moreover, fibers can be digested by commensal flora, thus producing compounds such as butyrate, which exerts an antiproliferative effect. Finally, fibers may modulate gut microbiota, whose composition has shown to be associated with CRC onset. In this regard, dietary interventions based on high-fiber-containing diets are ongoing to prevent CRC development, especially in patients with high potential for this type of tumor. Despite the fact that outcomes are preliminary, encouraging results have been observed.
Topics: Humans; Dietary Fiber; Plant Structures; Antioxidants; Bile Acids and Salts; Colorectal Neoplasms
PubMed: 37686308
DOI: 10.3390/ijms241713501