Impact of dietary fat on gut microbiota and low-grade systemic inflammation: mechanisms and clinical implications on obesity

Treating chronic stress and chronic pain by manipulating gut microbiota with diet: can we kill two birds with one stone?

Background: Chronic stress and chronic pain are closely linked by the capacity to exacerbate each other, sharing common roots in the brain and in the gut. The strict intersection between these two neurological diseases makes important to have a therapeutic strategy aimed at preventing both to maintain mental health in patients. Diet is an modifiable lifestyle factor associated with gut-brain axis diseases and there is growing interest in its use as adjuvant to main therapies. Several evidence attest the impact of specific diets or nutrients on chronic stress-related disorders and pain with a good degree of certainty. A daily adequate intake of foods containing micronutrients such as amino acids, minerals and vitamins, as well as the reduction in the consumption of processed food products can have a positive impact on microbiota and gut health. Many nutrients are endowed of prebiotic, anti-inflammatory, immunomodulatory and neuroprotective potential which make them useful tools helping the management of chronic stress and pain in patients. Dietary regimes, as intermittent fasting or caloric restriction, are promising, although further studies are needed to optimize protocols according to patient's medical history, age and sex. Moreover, by supporting gut microbiota health with diet is possible to attenuate comorbidities such as obesity, gastrointestinal dysfunction and mood disorders, thus reducing healthcare costs related to chronic stress or pain.Objective: This review summarize the most recent evidence on the microbiota-mediated beneficial effects of macro- and micronutrients, dietary-related factors, specific nutritional regimens and dietary intervention on these pathological conditions.

Faecal lipid profile as a new marker of fat maldigestion, malabsorption and microbiota

BACKGROUND

Fat malabsorption in children with cystic fibrosis (CF) leads to poor nutritional status and altered colonic microbiota. This study aimed at establishing the faecal lipid profile in children with CF, and exploring associations between the faecal lipidome and microbiota.

METHODS

Cross-sectional observational study with children with CF and an age-matched control group. Faecal lipidome was analysed by UHLC-HRMS and microbiota profiling by 16S rRNA amplicon sequencing.

RESULTS

Among 234 identified lipid species, five lipidome clusters (LC) were obtained with significant differences in triacylglycerols (TG), diacylglycerols (DG), monoacylglycerols (MG) and fatty-acids (FA): LC1 subjects with good digestion and absorption: low TG and low MG and FA; LC2 good digestion and poor absorption: low TG and high MG and FA; LC3 Mild digestion and poor absorption: intermediate TG and high MG and FA; LC4 poor digestion and absorption: high TG and high MG and FA; LC5 outliers. Bacteroidota and Verrucomicrobiota decreased over LC1-LC4, while Proteobacteria increased. Nutritional status indicators were significantly higher in LC1 and decreased over LC2-LC4.

CONCLUSION

Assessing faecal lipidome may be relevant to determine how dietary lipids are digested and absorbed. This new evidence might be a method to support targeted nutritional interventions towards reverting fat maldigestion or malabsorption.

IMPACT

Lipidomic analysis enabled the identification of the lipid species related to maldigestion (triglycerides) or malabsorption (monoglycerides and fatty acids). Children with cystic fibrosis can be grouped depending on the faecal lipidome profile related to dietary fat maldigestion or malabsorption. The lipidome profile in faeces is related to the composition of microbiota and nutritional status indicators.

Shifts in the functional capacity and metabolite composition of the gut microbiome during recovery from enteric infection

While enteric pathogens have been widely studied for their roles in causing foodborne infection, their impacts on the gut microbial community have yet to be fully characterized. Previous work has identified notable changes in the gut microbiome related to pathogen invasion, both taxonomically and genetically. Characterization of the metabolic landscape during and after enteric infection, however, has not been explored. Consequently, we investigated the metabolome of paired stools recovered from 60 patients (cases) during and after recovery from enteric bacterial infections (follow-ups). Shotgun metagenomics was applied to predict functional microbial pathways combined with untargeted metametabolomics classified by Liquid Chromatography Mass Spectrometry. Notably, cases had a greater overall metabolic capacity with significantly higher pathway richness and evenness relative to the follow-ups (p<0.05). Metabolic pathways related to central carbon metabolism, amino acid metabolism, and lipid and fatty acid biosynthesis were more highly represented in cases and distinct signatures for menaquinone production were detected. By contrast, the follow-up samples had a more diverse metabolic landscape with enhanced richness of polar metabolites (p<0.0001) and significantly greater richness, evenness, and overall diversity of nonpolar metabolites (p<0.0001). Although many metabolites could not be annotated with existing databases, a marked increase in certain clusters of metabolites was observed in the follow-up samples when compared to the case samples and vice versa. These findings suggest the importance of key metabolites in gut health and recovery and enhance understanding of metabolic fluctuations during enteric infections.

Investigation of the therapeutic effect of Hedan tablets on high-fat diet-induced obesity in rats by GC-MS technology and 16S ribosomal RNA gene sequencing

Obesity is a persistent metabolic condition resulting from the excessive accumulation or abnormal distribution of body fat. This study aimed to establish an experimental rat model of obesity. The efficacy of treating obesity with Hedan tablets (HDT) was assessed by monitoring changes in weight, blood lipid levels, analyzing inflammatory factors, evaluating organ indices, and observing liver tissue pathology. Furthermore, we utilized 16S ribosomal RNA gene sequencing technology to explore changes in intestinal flora. In addition, GC-MS was used to measure fecal short-chain fatty acid (SCFA) content. The onset of obesity led to a significant decrease in the relative abundance of beneficial bacteria. Conversely, the administration of HDT demonstrated a substantial ability to increase the relative abundance of beneficial bacteria. Obesity resulted in a noteworthy reduction in total SCFAs, a trend significantly reversed in the HDT group. Through correlation analysis, it was determined that HDT mitigated the inflammatory response and improved blood lipid levels by augmenting the abundance of Lactobacillus, Limosilactobacillus, Ruminococcus, and Enterococcus. These particular intestinal flora were identified as regulators of SCFA metabolism, thereby ameliorating metabolic abnormalities associated with obesity. Moreover, HDT intervention elevated the overall fecal concentration of SCFAs, thereby improving metabolic disorders induced by obesity. The anti-obesity effects of HDT are likely attributable to their capacity to influence the composition of intestinal flora and boost SCFA levels in the intestine.

Inflammatory potential of diet and mortality in Australian adults

OBJECTIVE

Inflammation is implicated in chronic diseases including cancer and CVD, which are major causes of mortality. Diet can influence inflammation status. We therefore examined whether the inflammatory potential of a person's diet is associated with mortality.

DESIGN

The inflammatory potential of the usual diet was assessed by calculating Dietary Inflammatory Index (DII) scores from repeated FFQ data (collected in 1992, 1994 and 1996), placing each participant's diet on a continuum from anti- to pro-inflammatory. DII scores were analysed as a continuous variable and as categories by creating quartile groups. Death registry data were used to ascertain all-cause mortality and separately mortality from CVD, cancers and other causes between 1992 and 2022. Cox proportional hazard regression analysis was used to calculate adjusted hazard ratios (HR) with 95 % CI, comparing higher and lowest quartile groups, or HR change per one DII unit increase.

SETTING

Nambour, Australia.

PARTICIPANTS

A community-based sample of 1440 adults aged 25-75 years.

RESULTS

During follow-up, 488 participants died, including 188 from CVD, 151 from cancer and 170 from other causes. Participants in the most pro-inflammatory diet group were at increased risk of all-cause mortality (HRQ4 v. Q1 = 1·55; 95 % CI 1·19, 2·03; P < 0·001) and other-cause mortality (HRQ4 v. Q1 = 1·69; 95 % CI 1·12, 2·54; P 0·01). A one-unit increase in DII score was associated with a 36 % increased risk of CVD among those younger than 55 years of age (HR for a one-unit increase in DII score 1·36, 95 % CI 1·04, 1·78). The risk of cancer mortality was also increased for those with a more pro-inflammatory diet in age ≤ 55 years (HR for a one-unit increase in DII score 1·20, 95 % CI 1·02, 1·40) and age 56-65 years (HR for a one-unit increase in DII score 1·11, 95 % CI 1·00, 1·23).

CONCLUSIONS

A pro-inflammatory diet increases the risk of all-cause mortality. Our results support the promotion of anti-inflammatory diets to help promote longevity.

The Effects of Food Nutrients and Bioactive Compounds on the Gut Microbiota: A Comprehensive Review

It is now widely recognized that gut microbiota plays a critical role not only in the development and progression of diseases, but also in its susceptibility to dietary patterns, food composition, and nutritional intake. In this comprehensive review, we have compiled the latest findings on the effects of food nutrients and bioactive compounds on the gut microbiota. The research indicates that certain components, such as unsaturated fatty acids, dietary fiber, and protein have a significant impact on the composition of bile salts and short-chain fatty acids through catabolic processes, thereby influencing the gut microbiota. Additionally, these compounds also have an effect on the ratio of Firmicutes to Bacteroides, as well as the abundance of specific species like Akkermansia muciniphila. The gut microbiota has been found to play a role in altering the absorption and metabolism of nutrients, bioactive compounds, and drugs, adding another layer of complexity to the interaction between food and gut microbiota, which often requires long-term adaptation to yield substantial outcomes. In conclusion, understanding the relationship between food compounds and gut microbiota can offer valuable insights into the potential therapeutic applications of food and dietary interventions in various diseases and health conditions.

Daily Cashew and Brazil Nut Consumption Modifies Intestinal Health in Overweight Women on Energy-Restricted Intervention: A Randomized Controlled Trial (Brazilian Nuts Study)

BACKGROUND

Increased intestinal permeability and dysbiosis are related to obesity. Nuts can provide nutrients and bioactive compounds that modulate gut microbiota and inflammation, enhancing the beneficial effects of weight loss.

OBJECTIVES

To evaluate the effect of consuming cashew nuts (Anacardium occidentale L.) and Brazil nuts (Bertholletia excelsa H.B.K) on intestinal permeability and microbiota, fecal SCFAs and pH, inflammation, and weight loss in energy restriction condition.

METHODS

In this 8-week randomized controlled trial, 40 women with overweight or obesity were assigned to energy-restricted groups (-500 kcal/d): control group (free of nuts) or Brazilian nuts group (BN: 30 g of cashew nuts and 15 g of Brazil nuts per day). Permeability was analyzed by the lactulose/mannitol test and the microbiota by sequencing the 16S gene in the V3-V4 regions. Plasma concentrations of inflammatory cytokines (TNF, IL-6, IL-10, IL-8, IL-17A) and C-reactive protein were analyzed.

RESULTS

In total, 25 women completed the intervention. Both groups lost weight without statistical differences. Lactulose excretion increased only in the control group (P < 0.05). The BN consumption increased fecal propionic acid and potentially beneficial bacteria, such as Ruminococcus, Roseburia, strains NK4A214 and UCG-002 from the Ruminococcaceae family, but also Lachnospiraceae family, Bacteroides, and Lachnoclostridium, when compared to the control group. Changes in intestinal permeability were correlated to a greater reduction in body fat (kg), and IL-8, and increases in Ruminococcus abundance.

CONCLUSION

Our findings demonstrate a positive impact of BN consumption within an energy-restricted context, linked to the augmentation of potentially beneficial bacteria and pathways associated with body fat reduction. Besides, BN consumption mitigated increased intestinal permeability, although its capacity to diminish permeability or enhance weight loss proved limited. This trial was registered at the Brazilian Registry of Clinical Trials as ReBEC (ID: RBR-3ntxrm).

Antifungal chemicals promising function in disease prevention, method of action and mechanism

The increasing use of antimicrobial drugs has been linked to the rise of drug-resistant fungus in recent years. Antimicrobial resistance is being studied from a variety of perspectives due to the important clinical implication of resistance. The processes underlying this resistance, enhanced methods for identifying resistance when it emerges, alternate treatment options for infections caused by resistant organisms, and so on are reviewed, along with strategies to prevent and regulate the formation and spread of resistance. This overview will focus on the action mechanism of antifungals and the resistance mechanisms against them. The link between antibacterial and antifungal resistance is also briefly discussed. Based on their mechanism action, antifungals are divided into three distinct categories: azoles, which target the ergosterol synthesis; 5-fluorocytosine, which targets macromolecular synthesis and polyenes, which interact physiochemically with fungal membrane sterols. Antifungal resistance can arise through a wide variety of ways. Overexpression of the target of the antifungal drug, changes to the drug target, changes to sterol biosynthesis, decreased intercellular concentration of the target enzyme, and other processes. A correlation exists between the mechanisms of resistance to antibacterial and antifungals, despite the fact that the comparison between the two is inevitably constrained by various parameters mentioned in the review. Drug extrusion via membrane pumps has been thoroughly documented in both prokaryotic and eukaryotic cells, and development of new antifungal compounds and strategies has also been well characterized.

Ginsenoside Rk3 Ameliorates Obesity-Induced Colitis by Modulating Lipid Metabolism in C57BL/6 Mice

Lipid metabolism is closely related to obesity and its complications. Our previous study found that ginsenoside Rk3 (Rk3), a natural bioactive substance derived from ginseng, can effectively alleviate obesity-induced colitis, while its impact on the improvement of the lipid metabolism disorder remains unclear. Here, we demonstrated that Rk3 significantly alleviated inflammation, oxidative stress, and lipid dysregulation in high-fat diet-induced colitis C57BL/6 mice. The potential mechanism by which Rk3 mitigated colon inflammation in the context of obesity may involve the modulation of polyunsaturated fatty acid metabolism with specific attention to n-6 fatty acids, linoleic acid, and arachidonic acid. Rk3 intervention markedly reduced the production of pro-inflammatory factors (PGE2, PGD2, TXB2, HETE, and HODE) by inhibiting cyclooxygenase and lipoxygenase pathways, while enhancing the production of anti-inflammatory factors (EET and diHOME) via cytochrome P450 pathways. Our findings suggest that Rk3 is a potential anti-inflammatory natural drug that can improve obesity-induced intestinal inflammation by regulating lipid metabolism.

Long-chain polyunsaturated fatty acids influence colorectal cancer progression via the interactions between the intestinal microflora and the macrophages

The metabolism of long-chain polyunsaturated fatty acids (LCPUFAs) is closely associated with the risk and progression of colorectal cancer (CRC). This paper aims to investigate the role of LCPUFA in the crosstalk between intestinal microflora and macrophages, as well as the effects of these three parties on the progression of CRC. The metabolism and function of LCPUFA play important roles in regulating the composition of the human gut microflora and participating in the regulation of inflammation, ultimately affecting macrophage function and polarization, which is crucial in the tumor microenvironment. The effects of LCPUFA on cellular interactions between the two species can ultimately influence the progression of CRC. In this review, we explore the molecular mechanisms and clinical applications of LCPUFA in the interactions between intestinal microflora and intestinal macrophages, as well as its significance for CRC progression. Furthermore, we reveal the role of LCPUFA in the construction of the CRC microenvironment and explore the key nodes of the interactions between intestinal flora and intestinal macrophages in the environment. It provides potential targets for the metabolic diagnosis and treatment of CRC.

Chronic Stress as a Risk Factor for Type 2 Diabetes: Endocrine, Metabolic, and Immune Implications

BACKGROUND

Chronic stress is a condition of pressure on the brain and whole body, which in the long term may lead to a frank disease status, even including type 2 diabetes (T2D). Stress activates the hypothalamus-pituitary-adrenal axis with release of glucocorticoids (GCs) and catecholamines, as well as activation of the inflammatory pathway of the immune system, which alters glucose and lipid metabolism, ultimately leading to beta-cell destruction, insulin resistance and T2D onset. Alteration of the glucose and lipid metabolism accounts for insulin resistance and T2D outcome. Furthermore, stress-related subversion of the intestinal microbiota leads to an imbalance of the gut-brain-immune axis, as evidenced by the stress-related depression often associated with T2D. A condition of generalized inflammation and subversion of the intestinal microbiota represents another facet of stress-induced disease. In fact, chronic stress acts on the gut-brain axis with multiorgan consequences, as evidenced by the association between depression and T2D. Oxidative stress with the production of reactive oxygen species and cytokine-mediated inflammation represents the main hallmarks of chronic stress. ROS production and pro-inflammatory cytokines represent the main hallmarks of stress-related disorders, and therefore, the use of natural antioxidant and anti-inflammatory substances (nutraceuticals) may offer an alternative therapeutic approach to combat stress-related T2D. Single or combined administration of nutraceuticals would be very beneficial in targeting the neuro-endocrine-immune axis, thus, regulating major pathways involved in T2D onset. However, more clinical trials are needed to establish the effectiveness of nutraceutical treatment, dosage, time of administration and the most favorable combinations of compounds. Therefore, in view of their antioxidant and anti-inflammatory properties, the use of natural products or nutraceuticals for the treatment of stress-related diseases, even including T2D, will be discussed. Several evidences suggest that chronic stress represents one of the main factors responsible for the outcome of T2D.

The transplantation of the gut microbiome of fat-1 mice protects against colonic mucus layer disruption and endoplasmic reticulum stress induced by high fat diet

High-fat diets alter gut barrier integrity, leading to endotoxemia by impacting epithelial functions and inducing endoplasmic reticulum (ER) stress in intestinal secretory goblet cells. Indeed, ER stress, which is an important contributor to many chronic diseases such as obesity and obesity-related disorders, leads to altered synthesis and secretion of mucins that form the protective mucus barrier. In the present study, we investigated the relative contribution of omega-3 polyunsaturated fatty acid (PUFAs)-modified microbiota to alleviating alterations in intestinal mucus layer thickness and preserving gut barrier integrity. Male fat-1 transgenic mice (exhibiting endogenous omega-3 PUFAs tissue enrichment) and wild-type (WT) littermates were fed either an obesogenic high-fat diet (HFD) or a control diet. Unlike WT mice, HFD-fed fat-1 mice were protected against mucus layer alterations as well as an ER stress-mediated decrease in mucin expression. Moreover, cecal microbiota transferred from fat-1 to WT mice prevented changes in the colonic mucus layer mainly through colonic ER stress downregulation. These findings highlight a novel feature of the preventive effects of omega-3 fatty acids against intestinal permeability in obesity-related conditions.

Sweet, bloody consumption - what we eat and how it affects vascular ageing, the BBB and kidney health in CKD

In today's industrialized society food consumption has changed immensely toward heightened red meat intake and use of artificial sweeteners instead of grains and vegetables or sugar, respectively. These dietary changes affect public health in general through an increased incidence of metabolic diseases like diabetes and obesity, with a further elevated risk for cardiorenal complications. Research shows that high red meat intake and artificial sweeteners ingestion can alter the microbial composition and further intestinal wall barrier permeability allowing increased transmission of uremic toxins like p-cresyl sulfate, indoxyl sulfate, trimethylamine n-oxide and phenylacetylglutamine into the blood stream causing an array of pathophysiological effects especially as a strain on the kidneys, since they are responsible for clearing out the toxins. In this review, we address how the burden of the Western diet affects the gut microbiome in altering the microbial composition and increasing the gut permeability for uremic toxins and the detrimental effects thereof on early vascular aging, the kidney per se and the blood-brain barrier, in addition to the potential implications for dietary changes/interventions to preserve the health issues related to chronic diseases in future.

Metabolic Syndrome: A Narrative Review from the Oxidative Stress to the Management of Related Diseases

Metabolic syndrome (MS) is a growing disorder affecting thousands of people worldwide, especially in industrialised countries, increasing mortality. Oxidative stress, hyperglycaemia, insulin resistance, inflammation, dysbiosis, abdominal obesity, atherogenic dyslipidaemia and hypertension are important factors linked to MS clusters of different pathologies, such as diabesity, cardiovascular diseases and neurological disorders. All biochemical changes observed in MS, such as dysregulation in the glucose and lipid metabolism, immune response, endothelial cell function and intestinal microbiota, promote pathological bridges between metabolic syndrome, diabesity and cardiovascular and neurodegenerative disorders. This review aims to summarise metabolic syndrome's involvement in diabesity and highlight the link between MS and cardiovascular and neurological diseases. A better understanding of MS could promote a novel strategic approach to reduce MS comorbidities.

Combination of hyperlipidemia and 17β-Estradiol induces TMJOA-like pathological changes in rats

OBJECTIVE

We explored whether hyperlipidemia or combination of hyperlipidemia and E2 could induce TMJOA.

MATERIALS AND METHODS

Four groups of female rats were treated with normal diet, normal diet with E2, high-fat diet, and high-fat diet with E2 (HFD/E2), respectively, to induce TMJOA till 8 weeks. Another three groups were then used for COX2 inhibitor celecoxib to block the induction of TMJOA. Primary condylar chondrocytes were treated with combination of E2, ox-LDL, and corresponding inhibitors for evaluating expressions of related molecules.

RESULTS

Condylar cartilage proliferation with plenty of chondrocyte apoptosis and increased staining for LOX1, nuclear NF-κB, IL-1β, and COX2 at 4 weeks and decreased condylar cartilage and increased subchondral bone density at 8 weeks were observed only in the HFD/E2 group. Celecoxib significantly alleviated the cartilage proliferation and apoptosis in the HFD/E2 group. Serum ox-LDL increased in both high-fat diet groups, while serum IL-1β increased only in the HFD/E2 group. Combination of E2 and ox-LDL synergistically induced expressions of LOX1, phosphorylated NF-κB, IL-1β, and COX2, while LOX1 inhibitor blocked the induction of phosphorylated NF-κB, and NF-κB inhibitor the induction of IL-1β, and IL-1β inhibitor the induction of COX2.

CONCLUSION

Combination of hyperlipidemia and E2-induced TMJOA-like pathological changes through LOX1/NF-κB/IL-1β/COX2-signaling pathway.

Immune Remodeling during Aging and the Clinical Significance of Immunonutrition in Healthy Aging

Aging is associated with changes in the immune system and the gut microbiota. Immunosenescence may lead to a low-grade, sterile chronic inflammation in a multifactorial and dynamic way, which plays a critical role in most age-related diseases. Age-related changes in the gut microbiota also shape the immune and inflammatory responses. Nutrition is a determinant of immune function and of the gut microbiota. Immunonutrion has been regarded as a new strategy for disease prevention and management, including many age-related diseases. However, the understanding of the cause-effect relationship is required to be more certain about the role of immunonutrition in supporting the immune homeostasis and its clinical relevance in elderly individuals. Herein, we review the remarkable quantitative and qualitative changes during aging that contribute to immunosenescence, inflammaging and microbial dysbiosis, and the effects on late-life health conditions. Furthermore, we discuss the clinical significance of immunonutrition in the treatment of age-related diseases by systematically reviewing its modulation of the immune system and the gut microbiota to clarify the effect of immunonutrition-based interventions on the healthy aging.

Understanding the impact of radical changes in diet and the gut microbiota on brain function and structure: rationale and design of the EMBRACE study

BACKGROUND

Bariatric surgery leads to profound changes in gut microbiota and dietary patterns, both of which may interact to impact gut-brain communication. Though cognitive function improves postsurgery, there is a large variability in outcomes. How bariatric surgery-induced modifications in the gut microbiota and dietary patterns influence the variability in cognitive function is still unclear.

OBJECTIVES

To elucidate the associations between bariatric surgery-induced changes in dietary and gut microbiota patterns with cognition and brain structure.

SETTING

University hospital.

METHODS

A total of 120 adult patients (≥30 years) scheduled to undergo a primary bariatric surgery along with 60 age-, sex-, and body mass index-matched patients on the surgery waitlist will undergo assessments 3-months presurgery and 6- and 12-month postsurgery (or an equivalent time for the waitlist group). Additionally, 60 age-and sex-matched nonbariatric surgery eligible individuals will complete the presurgical assessments only. Evaluations will include sociodemographic and health behavior questionnaires, physiological assessments (anthropometrics, blood-, urine-, and fecal-based measures), neuropsychological cognitive tests, and structural magnetic resonance imaging. Cluster analyses of the dietary and gut microbiota changes will define the various dietary patterns and microbiota profiles, then using repeated measures mixed models, their associations with global cognitive and structural brain alterations will be explored.

RESULTS

The coordinating study site (Centre intégré universitaire de santé et de services sociaux du Nord-de-l'Île-de-Montréal, QC, Canada), provided the primary ethical approval (Research Ethics Board#: MP-32-2022-2412).

CONCLUSIONS

The insights generated from this study can be used to develop individually-targeted neurodegenerative disease prevention strategies, as well as providing critical mechanistic information.

Nutritional Support for Liver Diseases

The liver is a key organ that is responsible for the metabolism of proteins, fats, and carbohydrates and the absorption and storage of micronutrients. Unfortunately, the prevalence of chronic liver diseases at various stages of advancement in the world population is significant. Due to the physiological function of the liver, its dysfunction can lead to malnutrition and sarcopenia, and the patient's nutritional status is an important prognostic factor. This review discusses key issues related to the diet therapy of patients with chronic liver diseases, as well as those qualified for liver transplantation and in the postoperative period.

Evaluation of Peri-Implant Parameters and C-Reactive Protein Levels among Patients with Different Obesity Levels

Background

Assessment of correlation between peri-implant parameters and C-reactive protein levels among patients with different obesity levels.

Materials and Methods

Evaluation of 60 subjects was performed who were scheduled to undergo dental implant therapy for missing mandibular first molars. Three study cohorts were formed, namely, Group A: obese group (BMI between 30 Kg/m2 and 34.9 Kg/m2), Group B: high obese group (BMI over 34.9 Kg/m2), and Group C: non-obese group (BMI under 25 Kg/m2). Each cohort comprised 20 subjects. Dental implant therapy was carried out in all the patients. Peri-implant variables were evaluated in all the patients. Blood samples were obtained, and C-reactive protein levels in subjects having different obesity levels. Statistical analysis was performed using SPSS software.

Results

Mean serum C-reactive protein levels among patients of groups A, B, and C occurred to be 3.28 mg/L, 3.65 g/L, and 3.61 g/L, respectively. On comparing numerically, noticeable outcomes were achieved. Mean probing depth among subjects of groups A, B, and C occurred to be 2.9 mm, 3.2 mm, and 1.3 mm, respectively. Mean marginal bone loss among subjects of groups A, B, and C occurred to be 2.1 mm, 2.7 mm, and 0.8 mm, respectively. On comparing numerically, noteworthy outcomes were gathered.

Conclusion

There were significantly higher deranged peri-implant inflammatory variables among patients with higher levels of obesity.

Dietary Patterns, Gut Microbiota Remodeling, and Cardiometabolic Disease

The cardiovascular and metabolic disorders, collectively known as cardiometabolic disease (CMD), are high morbidity and mortality pathologies associated with lower quality of life and increasing health-care costs. The influence of the gut microbiota (GM) in dictating the interpersonal variability in CMD susceptibility, progression and treatment response is beginning to be deciphered, as is the mutualistic relation established between the GM and diet. In particular, dietary factors emerge as pivotal determinants shaping the architecture and function of resident microorganisms in the human gut. In turn, intestinal microbes influence the absorption, metabolism, and storage of ingested nutrients, with potentially profound effects on host physiology. Herein, we present an updated overview on major effects of dietary components on the GM, highlighting the beneficial and detrimental consequences of diet-microbiota crosstalk in the setting of CMD. We also discuss the promises and challenges of integrating microbiome data in dietary planning aimed at restraining CMD onset and progression with a more personalized nutritional approach.

Diets, Gut Microbiota and Metabolites

The gut microbiota refers to the gross collection of microorganisms, estimated trillions of them, which reside within the gut and play crucial roles in the absorption and digestion of dietary nutrients. In the past decades, the new generation 'omics' (metagenomics, transcriptomics, proteomics, and metabolomics) technologies made it possible to precisely identify microbiota and metabolites and describe their variability between individuals, populations and even different time points within the same subjects. With massive efforts made, it is now generally accepted that the gut microbiota is a dynamically changing population, whose composition is influenced by the hosts' health conditions and lifestyles. Diet is one of the major contributors to shaping the gut microbiota. The components in the diets vary in different countries, religions, and populations. Some special diets have been adopted by people for hundreds of years aiming for better health, while the underlying mechanisms remain largely unknown. Recent studies based on volunteers or diet-treated animals demonstrated that diets can greatly and rapidly change the gut microbiota. The unique pattern of the nutrients from the diets and their metabolites produced by the gut microbiota has been linked with the occurrence of diseases, including obesity, diabetes, nonalcoholic fatty liver disease, cardiovascular disease, neural diseases, and more. This review will summarize the recent progress and current understanding of the effects of different dietary patterns on the composition of gut microbiota, bacterial metabolites, and their effects on the host's metabolism.

Dietary fat intakes, lipid profiles, adiposity, inflammation, and glucose in women and men in the Framingham Offspring Cohort

Introduction: The role of dietary fat in the evolution of cardiometabolic disorders is highly controversial. As both dietary intake and the development of cardiometabolic risk differ by sex, we evaluated sex-specific differences in the associations between dietary fats (saturated and unsaturated) and four key cardiometabolic risk factors-lipid profiles, body fat, inflammation, and glucose regulation. Methods: We included 2391 women and men aged ≥30 years in the prospective Framingham Offspring Cohort. Weight-adjusted dietary fats (saturated, monounsaturated, and polyunsaturated fats, including omega-3 and omega-6) were derived from 3-day dietary records. Analysis of covariance was used to derive adjusted mean levels of all outcomes. Results: In both men and women, intakes of saturated and monounsaturated fats were inversely associated with TG:HDL ratio (p < 0.02 for both types of fat). In women, higher omega-3 and omega-6 PUFAs were also inversely associated with TG:HDL (p < 0.05 for both), but for men, only omega-3 PUFAs were associated (p = 0.026). All types of dietary fat were beneficially associated with larger HDL particle sizes in both men and women, while only saturated and monounsaturated fats were associated with larger LDL particles in men. In addition, saturated and monounsaturated fats were associated with statistically significantly higher concentrations of HDL and lower concentrations of LDL and VLDL particles in both sexes, while polyunsaturated fat had favorable associations in women only. Saturated fat also had beneficial associations with three measures of body fat. For example, women with the highest (vs. lowest) saturated fat intake had a lower BMI (27.7 ± 0.25 vs. 26.2 ± 0.36 kg/m², p = 0.001); findings were similar in men (28.2 ± 0.25 vs. 27.1 ± 0.20, p = 0.002). Unsaturated fats had beneficial associations with body fat primarily in women. Finally, omega-3 PUFAs among women were inversely associated with interleukin-6 levels. There was no association between dietary fat intake and fasting glucose levels in either women or men. Discussion: In sum, we found no evidence of an adverse association between dietary fats and several surrogate markers of cardiometabolic health. This study suggests that different dietary fats may have divergent associations with cardiometabolic risk in women and men, perhaps owing to differences in food sources of the same dietary fats.

The Effects of the Mediterranean Diet on Health and Gut Microbiota

The Mediterranean Diet (MD) is plant-based and consists of multiple daily portions of vegetables, fruit, cereals, and olive oil. Although there are challenges with isolating the MD from the typical Mediterranean lifestyle and culture (including prolonged 'social' meals and siestas), much evidence supports the health benefits of the MD that include improved longevity, reduced metabolic risk of Diabetes Mellitus, obesity, and Metabolic Syndrome, reduced risk of malignancy and cardiovascular disease, and improved cognitive function. The MD is also associated with characteristic modifications to gut microbiota, mediated through its constituent parts (primarily dietary fibres, extra virgin olive oil, and polyunsaturated fatty acids [including ω-3]). These include enhanced growth of species that produce short-chain fatty acids (butyrate), such as Clostridium leptum and Eubacterium rectale, enhanced growth of Bifidobacteria, Bacteroides, and Faecalibacterium prausnitzii species, and reduced growth of Firmicutes and Blautia species. Such changes in gut microbiota are known to be associated favourably with inflammatory and oxidative status, propensity for malignancy and overall metabolic health. A key challenge for the future is to explore the extent to which the health benefits of the MD are mediated by such changes to gut microbiota. The MD confers both health and environmental benefits. Adoption of the MD should perhaps be encouraged and facilitated more generally and not just restricted to populations from Mediterranean regions. However, there are key challenges to this approach that include limited perennial availability of the constituent parts of the MD in some non-Mediterranean regions, intolerability of a high-fibre diet for some people, and potential cultural disconnects that juxtapose some traditional (including Western) diets with the MD.

Patients with Diverticular Disease Have Different Dietary Habits Compared to Control Subjects: Results from an Observational Italian Study

The role of dietary habits as risk factor for the development of diverticular complications has strongly emerged in the last years. We aimed to evaluate possible differences in dietary habits between patients with diverticular disease (DD) and matched controls without diverticula. Dietary habits were obtained from standardized food frequency questionnaires collected at entry to the Diverticular Disease Registry (REMAD). We compared controls (C) (n = 119) with asymptomatic diverticulosis (D) (n = 344), symptomatic uncomplicated diverticular disease (SUDD) (n = 154) and previous diverticulitis (PD) (n = 83) patients, in terms of daily calories, macro and micronutrients and dietary vitamins. Daily kcal intake and lipids, both saturated and unsaturated, were significantly lower in patients with DD than C. Total protein consumption was lower in PD than D, with differing consumption of unprocessed red meat, white meat and eggs between groups. Consumption of fibre, both soluble and insoluble, was lower in patients with PD compared to patients with SUDD, D and C, whereas dietary vitamins A, C, D and E and Oxygen Radical Adsorbance Capacity index were lower in all DD groups compared to C. This observational study showed that DD patients have different dietary habits, mainly in terms of caloric, fat, fibre and vitamin intake, compared to control subjects.

Short-Term Alternate Feeding between Terrestrially Sourced Oil- and Fish Oil-Based Diets Modulates the Intestinal Microecology of Juvenile Turbot

A nine-week feeding trial was conducted to investigate changes in the intestinal microbiota of turbot in response to alternate feeding between terrestrially sourced oil (TSO)- and fish oil (FO)-based diets. The following three feeding strategies were designed: (1) continuous feeding with the FO-based diet (FO group); (2) weekly alternate feeding between soybean oil (SO)- and FO-based diets (SO/FO group); and (3) weekly alternate feeding between beef tallow (BT)- and FO-based diets (BT/FO group). An intestinal bacterial community analysis showed that alternate feeding reshaped the intestinal microbial composition. Higher species richness and diversity of the intestinal microbiota were observed in the alternate-feeding groups. A PCoA analysis showed that the samples clustered separately according to the feeding strategy, and among the three groups, the SO/FO group clustered relatively closer to the BT/FO group. The alternate feeding significantly decreased the abundance of Mycoplasma and selectively enriched specific microorganisms, including short-chain fatty acid (SCFA)-producing bacteria, digestive bacteria (Corynebacterium and Sphingomonas), and several potential pathogens (Desulfovibrio and Mycobacterium). Alternate feeding may maintain the intestinal microbiota balance by improving the connectivity of the ecological network and increasing the competitive interactions within the ecological network. The alternate feeding significantly upregulated the KEGG pathways of fatty acid and lipid metabolism, glycan biosynthesis, and amino acid metabolism in the intestinal microbiota. Meanwhile, the upregulation of the KEGG pathway of lipopolysaccharide biosynthesis indicates a potential risk for intestinal health. In conclusion, short-term alternate feeding between dietary lipid sources reshapes the intestinal microecology of the juvenile turbot, possibly resulting in both positive and negative effects.

The roles of dietary lipids and lipidomics in gut-brain axis in type 2 diabetes mellitus

Type 2 diabetes mellitus (T2DM), one of the main types of Noncommunicable diseases (NCDs), is a systemic inflammatory disease characterized by dysfunctional pancreatic β-cells and/or peripheral insulin resistance, resulting in impaired glucose and lipid metabolism. Genetic, metabolic, multiple lifestyle, and sociodemographic factors are known as related to high T2DM risk. Dietary lipids and lipid metabolism are significant metabolic modulators in T2DM and T2DM-related complications. Besides, accumulated evidence suggests that altered gut microbiota which plays an important role in the metabolic health of the host contributes significantly to T2DM involving impaired or improved glucose and lipid metabolism. At this point, dietary lipids may affect host physiology and health via interaction with the gut microbiota. Besides, increasing evidence in the literature suggests that lipidomics as novel parameters detected with holistic analytical techniques have important roles in the pathogenesis and progression of T2DM, through various mechanisms of action including gut-brain axis modulation. A better understanding of the roles of some nutrients and lipidomics in T2DM through gut microbiota interactions will help develop new strategies for the prevention and treatment of T2DM. However, this issue has not yet been entirely discussed in the literature. The present review provides up-to-date knowledge on the roles of dietary lipids and lipidomics in gut-brain axis in T2DM and some nutritional strategies in T2DM considering lipids- lipidomics and gut microbiota interactions are given.

Time-Restricted Feeding Modifies the Fecal Lipidome and the Gut Microbiota

Time-restricted feeding (TRF) has been identified as an approach to reduce the risk of obesity-related metabolic diseases. We hypothesize that TRF triggers a change in nutrient (e.g., dietary fat) absorption due to shortened feeding times, which subsequently alters the fecal microbiome and lipidome. In this report, three groups of C57BL/6 mice were fed either a control diet with ad libitum feeding (16% energy from fat) (CTRL-AL), a high-fat diet (48% energy from fat) with ad libitum feeding (HF-AL), or a high-fat diet with time-restricted feeding (HF-TRF) for 12 weeks. No changes in microbiota at the phylum level were detected, but eight taxonomic families were altered by either feeding timing or dietary fat content. The HF-AL diet doubled the total fecal fatty acid content of the CTRL-AL diet, while the HF-TRF doubled the total fecal fatty acid content of the HF-AL diet. Primary fecal bile acids were unaffected by diet. Total short-chain fatty acids were reduced by HF-AL, but this effect was diminished by HF-TRF. Each diet produced distinct relationships between the relative abundance of taxa and fecal lipids. The anti-obesogenic effects of TRF in HF diets are partly due to the increase in fat excretion in the feces. Furthermore, fat content and feeding timing differentially affect the fecal microbiota and the relationship between the microbiota and fecal lipids.

How Do Diet Patterns, Single Foods, Prebiotics and Probiotics Impact Gut Microbiota?

The human gastrointestinal tract hosts a complex and dynamic population of commensal bacterial species, which have coevolved with the host, generating a symbiotic relationship. Some compounds present in foods, such as polyols, prebiotic fibers, or phenolic compounds, are poorly metabolized and absorbed by the host before the transformation guided by the colonic microbiota. By influencing gut microbiota, diet plays a fundamental role in understanding the beneficial effects of the gut microbiota on the host, including its long-term metabolism. The idea that probiotics can act not only by influencing the colonizing microbiota opens the door to a wider range of probiotic possibilities, encouraging innovation in the field. Furthermore, it has been shown both that some probiotics increase phagocytosis or the activity of natural killer cells. Current prebiotics are mainly based on carbohydrates, but other substances, such as polyphenols and polyunsaturated fatty acids, could exert prebiotic effects. A prebiotic substance has been defined as ‘a substrate that is selectively used by host microorganisms that confer a health benefit’, and so can interact with the gut microbiota through competition for nutrients, antagonism, cross-feeding, and support for microbiota stability. Influencing its composition in terms of richness and diversity, food components have a key impact on the intestinal microbiota. Eating habits can strongly influence the composition of the intestinal microbiota. A healthy intestinal microbiota is essential for maintaining general health, and diet is one of the major modulators of this fascinating world of microorganisms. This must give us one more reason to adopt a healthy lifestyle.

The Interplay of Dietary Fibers and Intestinal Microbiota Affects Type 2 Diabetes by Generating Short-Chain Fatty Acids

Foods contain dietary fibers which can be classified into soluble and insoluble forms. The nutritional composition of fast foods is considered unhealthy because it negatively affects the production of short-chain fatty acids (SCFAs). Dietary fiber is resistant to digestive enzymes in the gut, which modulates the anaerobic intestinal microbiota (AIM) and fabricates SCFAs. Acetate, butyrate, and propionate are dominant in the gut and are generated via Wood-Ljungdahl and acrylate pathways. In pancreatic dysfunction, the release of insulin/glucagon is impaired, leading to hyperglycemia. SCFAs enhance insulin sensitivity or secretion, beta-cell function, leptin release, mitochondrial function, and intestinal gluconeogenesis in human organs, which positively affects type 2 diabetes (T2D). Research models have shown that SCFAs either enhance the release of peptide YY (PYY) and glucagon-like peptide-1 (GLP-1) from L-cells (entero-endocrine), or promotes the release of leptin hormone in adipose tissues through G-protein receptors GPR-41 and GPR-43. Dietary fiber is a component that influences the production of SCFAs by AIM, which may have beneficial effects on T2D. This review focuses on the effectiveness of dietary fiber in producing SCFAs in the colon by the AIM as well as the health-promoting effects on T2D.

Water Extract of Chrysanthemum indicum L. Flower Inhibits Capsaicin-Induced Systemic Low-Grade Inflammation by Modulating Gut Microbiota and Short-Chain Fatty Acids

Systemic low-grade inflammation induced by unhealthy diet has become a common health concern as it contributes to immune imbalance and induces chronic diseases, yet effective preventions and interventions are currently unavailable. The Chrysanthemum indicum L. flower (CIF) is a common herb with a strong anti-inflammatory effect in drug-induced models, based on the theory of "medicine and food homology". However, its effects and mechanisms in reducing food-induced systemic low-grade inflammation (FSLI) remain unclear. This study showed that CIF can reduce FSLI and represents a new strategy to intervene in chronic inflammatory diseases. In this study, we administered capsaicin to mice by gavage to establish a FSLI model. Then, three doses of CIF (7, 14, 28 g·kg^-1·day^-1) were tested as the intervention. Capsaicin was found to increase serum TNF-α levels, demonstrating a successful model induction. After a high dose of CIF intervention, serum levels of TNF-α and LPS were reduced by 62.8% and 77.44%. In addition, CIF increased the α diversity and number of OTUs in the gut microbiota, restored the abundance of Lactobacillus and increased the total content of SCFAs in the feces. In summary, CIF inhibits FSLI by modulating the gut microbiota, increasing SCFAs levels and inhibiting excessive LPS translocation into the blood. Our findings provided a theoretical support for using CIF in FSLI intervention.

Amelioration of obesity-induced white adipose tissue inflammation by Bacillus coagulans T4 in a high-fat diet-induced obese murine model

AIM

Fresh evidence suggests that B. coagulans can be regarded as a promising therapeutic alternative for metabolic disorders. However, the possible effects of this probiotic on obesity-induced adipose tissue inflammation are unknown.

METHODS

C57BL/6j male mice were assigned to a normal-chow diet (NCD) or a high-fat diet (HFD) for 10 weeks. After this period, HFD-fed mice were randomly divided into two groups; HFD control group and HFD plus B. coagulans T4 (IBRC-N10791) for another 8 weeks. B. coagulans T4 was administrated daily by oral intragastric gavage (1 × 10⁹ colony-forming units).

KEY FINDINGS

Here, we found that B. coagulans successfully mitigated obesity and related metabolic disorder, as indicated by reduced body weight gain, decreased adiposity, and improved glucose tolerance. B. coagulans T4 administration also inhibited HFD-induced macrophage accumulation in white adipose tissue and switched M1 to M2 macrophages. In parallel, B. coagulans T4 treatment attenuated HFD-induced alteration in mRNA expression of pro/anti-inflammatory cytokines and Tlr4 in white adipose tissue. Moreover, B. coagulans T4 supplementation reduced the Firmicutes/Bacteriodetes ratio and increased the number of Lactobacillus and Faecalibacterium compared to the HFD group. Additionally, a significant increase in propionate and acetate levels in the HFD group was seen following B. coagulans T4 administration.

SIGNIFICANCE

Taken together, the present study provides evidence that B. coagulans T4 supplementation exerts anti-obesity effects in part through attenuating inflammation in adipose tissue. The present study will have significant implications for obesity management.

Multi-omics profiles of the intestinal microbiome in irritable bowel syndrome and its bowel habit subtypes

BACKGROUND

Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that is thought to involve alterations in the gut microbiome, but robust microbial signatures have been challenging to identify. As prior studies have primarily focused on composition, we hypothesized that multi-omics assessment of microbial function incorporating both metatranscriptomics and metabolomics would further delineate microbial profiles of IBS and its subtypes.

METHODS

Fecal samples were collected from a racially/ethnically diverse cohort of 495 subjects, including 318 IBS patients and 177 healthy controls, for analysis by 16S rRNA gene sequencing (n = 486), metatranscriptomics (n = 327), and untargeted metabolomics (n = 368). Differentially abundant microbes, predicted genes, transcripts, and metabolites in IBS were identified by multivariate models incorporating age, sex, race/ethnicity, BMI, diet, and HAD-Anxiety. Inter-omic functional relationships were assessed by transcript/gene ratios and microbial metabolic modeling. Differential features were used to construct random forests classifiers.

RESULTS

IBS was associated with global alterations in microbiome composition by 16S rRNA sequencing and metatranscriptomics, and in microbiome function by predicted metagenomics, metatranscriptomics, and metabolomics. After adjusting for age, sex, race/ethnicity, BMI, diet, and anxiety, IBS was associated with differential abundance of bacterial taxa such as Bacteroides dorei; metabolites including increased tyramine and decreased gentisate and hydrocinnamate; and transcripts related to fructooligosaccharide and polyol utilization. IBS further showed transcriptional upregulation of enzymes involved in fructose and glucan metabolism as well as the succinate pathway of carbohydrate fermentation. A multi-omics classifier for IBS had significantly higher accuracy (AUC 0.82) than classifiers using individual datasets. Diarrhea-predominant IBS (IBS-D) demonstrated shifts in the metatranscriptome and metabolome including increased bile acids, polyamines, succinate pathway intermediates (malate, fumarate), and transcripts involved in fructose, mannose, and polyol metabolism compared to constipation-predominant IBS (IBS-C). A classifier incorporating metabolites and gene-normalized transcripts differentiated IBS-D from IBS-C with high accuracy (AUC 0.86).

CONCLUSIONS

IBS is characterized by a multi-omics microbial signature indicating increased capacity to utilize fermentable carbohydrates-consistent with the clinical benefit of diets restricting this energy source-that also includes multiple previously unrecognized metabolites and metabolic pathways. These findings support the need for integrative assessment of microbial function to investigate the microbiome in IBS and identify novel microbiome-related therapeutic targets. Video Abstract.

N-3 Polyunsaturated Fatty Acids and Gut Microbiota

For several decades, studies have reported that n-3 polyunsaturated fatty acids (PUFAs) play a beneficial role in cardiovascular, immune, cognitive, visual, mental and metabolic health. The mammalian intestine is colonized by microbiota, including bacteria, archaea, viruses, protozoans, and fungi. The composition of the gut microbiota is influenced by long-term dietary habits, disease-associated dysbiosis, and the use of antibiotics. Accumulating evidence suggests a relationship between n-3 PUFAs and the gut microbiota. N-3 PUFAs can alter the diversity and abundance of the gut microbiome, and gut microbiota can also affect the metabolism and absorption of n-3 PUFAs. Changes in the populations of certain gut microbiota can lead to negative effects on inflammation, obesity, and metabolic diseases. An imbalanced consumption of n-3/n-6 PUFAs may lead to gut microbial dysbiosis, in particular, a significant increase in the ratio of Firmicutes to Bacteroidetes, which eventually results in being overweight and obesity. N-3 PUFA deficiency disrupts the microbiota community in metabolic disorders. In addition, accumulating evidence indicates that the interplay between n-3 PUFAs, gut microbiota, and immune reactions helps to maintain the integrity of the intestinal wall and interacts with host immune cells. Supplementation with n-3 PUFAs may be an effective therapeutic measure to restore gut microbiota homeostasis and correct metabolic disturbances associated with modern chronic diseases. In particular, marine extracts from seaweed contain a considerable dry weight of lipids, including n-3 PUFAs such as eicosapentaenoic acid (EPA, C20: 5) and docosahexaenoic acid (DHA, C22: 6). This review describes how gut microbiota function in intestinal health, how n-3 PUFAs interact with the gut microbiota, and the potential of n-3 PUFAs to influence the gut-brain axis, acting through gut microbiota composition.

Interventions on Gut Microbiota for Healthy Aging

In recent years, the improvement in health and social conditions has led to an increase in the average lifespan. Since aging is the most important risk factor for the majority of chronic human diseases, the development of therapies and intervention to stop, lessen or even reverse various age-related morbidities is an important target to ameliorate the quality of life of the elderly. The gut microbiota, that is, the complex ecosystem of microorganisms living in the gastrointestinal tract, plays an important role, not yet fully understood, in maintaining the host's health and homeostasis, influencing metabolic, oxidative and cognitive status; for this reason, it is also named "the forgotten endocrine organ" or "the second brain". On the other hand, the gut microbiota diversity and richness are affected by unmodifiable factors, such as aging and sex, and modifiable ones, such as diet, pharmacological therapies and lifestyle. In this review, we discuss the changes, mostly disadvantageous, for human health, induced by aging, in microbiota composition and the effects of dietary intervention, of supplementation with probiotics, prebiotics, synbiotics, psychobiotics and antioxidants and of physical exercise. The development of an integrated strategy to implement microbiota health will help in the goal of healthy aging.

Molecular mechanisms of ferroptosis and relevance to inflammation

INTRODUCTION

Inflammation is a defensive response of the organism to irritation which is manifested by redness, swelling, heat, pain and dysfunction. The inflammatory response underlies the role of various diseases. Ferroptosis, a unique modality of cell death, driven by iron-dependent lipid peroxidation, is regulated by multifarious cellular metabolic pathways, including redox homeostasis, iron processing and metabolism of lipids, as well as various signaling pathways associated with diseases. A growing body of evidence suggests that ferroptosis is involved in inflammatory response, and targeting ferroptosis has great prospects in preventing and treating inflammatory diseases.

MATERIALS AND METHODS

Relevant literatures on ferroptosis, inflammation, inflammatory factors and inflammatory diseases published from January 1, 2010 to now were searched in PubMed database.

CONCLUSION

In this review, we summarize the regulatory mechanisms associated with ferroptosis, discuss the interaction between ferroptosis and inflammation, the role of mitochondria in inflammatory ferroptosis, and the role of targeting ferroptosis in inflammatory diseases. As more and more studies have confirmed the relationship between ferroptosis and inflammation in a wide range of organ damage and degeneration, drug induction and inhibition of ferroptosis has great potential in the treatment of immune and inflammatory diseases.

A Higher Healthy Eating Index Is Associated with Decreased Markers of Inflammation and Lower Odds for Being Overweight/Obese Based on a Case-Control Study

Obesity is a health risk characterized by chronic inflammation, and food choices are strongly associated with its etiology. Our objective was to investigate the association between dietary patterns and the healthy eating index (HEI) with the odds of overweight/obesity and related inflammatory markers. Within a population-based case-control study, we collected data and samples from 793 normal-weight and 812 overweight/obese Iranian people (based on either body mass index (BMI) or body surface area (BSA)). Dietary intake and HEI scores were obtained via a validated 124-item food frequency questionnaire. Anthropometric and socioeconomic parameters, as well as blood inflammatory markers, were measured. Participants with higher HEI scores had higher serum high-density lipoprotein-cholesterol (HDL-C) and significantly lower energy intake. Water consumption in the overweight/obese group was significantly lower than in the control group. In the final models using partial correlation and controlling for multiple confounders, there was a significant inverse correlation between HEI and interleukin-4 (IL-4, R = -0.063), IL-1β (R = -0.054), and high-sensitivity C-reactive protein (hs-CRP, R = -0.069). Based on multivariable logistic regression models adjusted for multiple confounders, there was a significant association between HEI as a continuous variable (OR = 0.993, 95% CI: 0.988-0.999) and categorical variable (OR = 0.801, 95% CI: 0.658-0.977) and odds of overweight/obesity across BMI groups. The dietary patterns in the case and control groups however were similar, and we failed to find a significant association between HEI and odds of overweight/obesity based on BSA. Adherence to healthy eating recommendations may be a prudent recommendation to prevent overweight/obesity and keeping inflammatory indicators low.

Implication of saturated fats in the aetiology of childhood attention deficit/hyperactivity disorder - A narrative review

Attention Deficit/Hyperactivity Disorder (ADHD) is the most common mental health disorder in the paediatric population. ADHD is highly comorbid with obesity, and has also been associated with poor dietary patterns such as increased consumption of refined carbohydrates and saturated fats. Although ADHD in children was associated with high consumption of saturated fats, so far there has been no evidence-based attempt to integrate dietary strategies controlling for intake of saturated fats into the etiological framework of the disorder. Evidence from human studies and animal models has shown that diets high in saturated fats are detrimental for the development of dopaminergic neurocircuitries, synthesis of neurofactors (e.g. brain derived neurotrophic factor) and may promote brain inflammatory processes. Notably, animal models provide evidence that early life consumption of a high saturated fats diet may impair the development of central dopamine pathways. In the present paper, we review the impact of high saturated fats diets on neurobiological processes in human studies and animal models, and how these associations may be relevant to the neuropathophysiology of ADHD in children. The validation of this relationship and its underlying mechanisms through future investigative studies could have implications for the prevention or exacerbation of ADHD symptoms, improve the understanding of the pathogenesis of the disorder, and help design future dietary studies in patients with ADHD.

Beneficial effects of monounsaturated fatty acid-rich blended oils with an appropriate polyunsaturated/saturated fatty acid ratio and a low n-6/n-3 fatty acid ratio on the health of rats

BACKGROUND

The effects of dietary fat on health are influenced by its fatty acid profile. We aimed to determine the effects of monounsaturated fatty acid (MUFA)-rich blended oils (BO) containing a balance of polyunsaturated fatty acids (PUFAs) and saturated fatty acids (SFAs) and with a low n-6/n-3 PUFA ratio on the health of rats fed normal or high-fat diets. The BO was obtained by mixing red palm oil, rice bran oil (RO), tea seed oil and flaxseed oil in appropriate proportions.

RESULTS

BO consumption reduced the serum low-density lipoprotein cholesterol (LDL-C), non-esterified fatty acid (NEFA), insulin (INS), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1 (IL-1), high-sensitivity C-reactive protein (hs-CRP), malondialdehyde (MDA), lipid peroxide (LPO) and oxidized LDL (ox-LDL) concentrations and the homeostasis model assessment of insulin resistance (HOMA-IR); it increased the high-density lipoprotein cholesterol (HDL-C), glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) concentrations, and the bone mineral density (BMD) versus control oil-containing normal and high-fat diets. BO also reduced the triglyceride (TG), hs-CRP, MDA, ox-LDL and reactive oxygen species (ROS) concentrations; and increased the serum HDL-C and SOD, and BMD versus RO-containing high-fat diets. Finally, BO reduced the glucose (GLU) and INS, and HOMA-IR; it increased HDL-C, SOD, femoral weight and BMD versus RO-containing normal diets.

CONCLUSION

BOs with an appropriate fatty acid profile have beneficial effects on the glucolipid metabolism, inflammation, oxidative stress and bone quality of rats when included in both normal and high-fat diets. © 2022 Society of Chemical Industry.

Anti-inflammatory mechanisms of polyphenols in adipose tissue: role of gut microbiota, intestinal barrier integrity and zinc homeostasis

Obesity is associated with an imbalance of micro-and macro-nutrients, gut dysbiosis, and a "leaky" gut phenomenon. Polyphenols, such as curcumin, resveratrol, and anthocyanins may alleviate the systemic effects of obesity, potentially by improving gut microbiota, intestinal barrier integrity (IBI), and zinc homeostasis. The essential micronutrient zinc plays a crucial role in the regulation of enzymatic processes, including inflammation, maintenance of the microbial ecology, and intestinal barrier integrity. In this review, we focus on IBI- which prevents intestinal lipopolysaccharide (LPS) leakage - as a critical player in polyphenol-mediated protective effects against obesity-associated white adipose tissue (WAT) inflammation. This occurs through mechanisms that block the movement of the bacterial endotoxin LPS across the gut barrier. Available research suggests that polyphenols reduce WAT and systemic inflammation via crosstalk with inflammatory NF-κB, the mammalian target of rapamycin (mTOR) signaling and zinc homeostasis.

Novel weight loss diet attenuates dietary-induced obesity in mice and might correlate with altered gut microbiota and metabolite profiles

Although many dietary patterns have been studied for weight loss, various limitations still exist. Therefore, we designed a novel weight loss diet (NWLD) with carbohydrate, protein, and fat (energy) contents of 45%, 20%, and 35%, respectively. The saturated fatty acids: monounsaturated fatty acids:polyunsaturated fatty acids ratio was 1:2:1, and the insoluble: soluble dietary fiber ratio was 2:1. We aimed to observe the effect of NWLD on weight loss and understand the underlying metabolic mechanisms. Twenty-nine male C57BL/6J mice were selected. Nine mice were fed ordinary feed in a blank control group, and the rest were fed a high-fat diet (HFD) to establish obese mouse models. Twelve weeks later, obesity models were established, and 10 obese mice were switched to NWLD feeding. Six weeks after switching the diet, the serum, intestinal feces, and kidneys of mice were collected. Obesity-related indicators, gut microbial composition, and fecal metabolite profiles of all the mice were determined, and the correlations among these indicators were analyzed. Kidney function indicators were also assessed. The results showed that the NWLD attenuated HFD-induced weight gain, serum triglycerides (TG), and inflammatory factors, optimized the body composition without kidney function impairment. Amino acid metabolism pathways and metabolites might play key roles in this process. The findings of this research imply that NWLD could be an effective nutritional remedy for managing dietary-induced obesity.

Flaxseed oil ameliorates aging in d-galactose induced rats via altering gut microbiota and mitigating oxidative damage

BACKGROUND

Aging causes decreased antioxidant capacity and chronic inflammation and may even elevate cancer risks. Previous studies reported that flaxseed oil (FO) can alleviate age-related diseases, including improving alcoholic liver disease, atherosclerosis and diabetes. However, whether the intestinal microbiota accountable for this alleviation is still unknown. This study aims to study the antioxidant effects of FO in an aging rat model and the underlying mechanism between the intestinal microbiota and aging.

RESULTS

Our results presented that serum and liver antioxidant capacities in FO group were up-regulated, and liver inflammation in FO group was reduced. The 16S rDNA sequencing showed that FO regulated the microbial community, including up-regulation of four families of Lactobacillus and six families of Clostridium. In addition, FO had also adjusted the relative abundance of several genera such as Ruminococcaceae_UCG-005 and Prevotella_9, which may be the key bacteria associated with the aging process. Colonic transcriptome analysis showed that there were 1679 differentially expressed genes (DEGs) in the Model group and the FO group (134 up-regulated and 1545 down-regulated). Gene set enrichment analysis (GSEA) revealed FO down-regulates the expression of the upstream genes Ptprc, Lck, Zap70, Lat and Lcp2 in the T cell receptor signaling pathway.

CONCLUSION

In conclusion, FO improved antioxidant capacity and reduced intestinal microbial disturbances caused by aging damage, indicating that dietary FO has the potential to fight aging damage. This study provides a more comprehensive view of dietary intervention to improve aging. © 2022 Society of Chemical Industry.

Cistanche tubulosa phenylethanoid glycosides suppressed adipogenesis in 3T3-L1 adipocytes and improved obesity and insulin resistance in high-fat diet induced obese mice

Background

Cistanche tubulosa is an editable and medicinal traditional Chinese herb and phenylethanoid glycosides are its major components, which have shown various beneficial effects such as anti-tumor, anti-oxidant and neuroprotective activities. However, the anti-obesity effect of C. tubulosa phenylethanoid glycosides (CTPG) and their regulatory effect on gut microbiota are still unclear. In the present study, we investigated its anti-obesity effect and regulatory effect on gut microbiota by 3T3-L1 cell model and obesity mouse model.

Methods

3T3-L1 adipocytes were used to evaluate CTPG effects on adipogenesis and lipids accumulation. Insulin resistant 3T3-L1 cells were induced and used to measure CTPG effects on glucose consumption and insulin sensitivity. High-fat diet (HFD)-induced C57BL/6 obese mice were used to investigate CTPG effects on fat deposition, glucose and lipid metabolism, insulin resistance and intestinal microorganism.

Results

In vitro data showed that CTPG significantly decreased the triglyceride (TG) and non-esterified fatty acid (NEFA) contents of the differentiated 3T3-L1 adipocytes in a concentration-dependent manner without cytotoxicity, and high concentration (100 µg/ml) of CTPG treatment dramatically suppressed the level of monocyte chemoattractant protein-1 (MCP-1) in 3T3-L1 mature adipocytes. Meanwhile, CTPG increased glucose consumption and decreased NEFA level in insulin resistant 3T3-L1 cells. We further found that CTPG protected mice from the development of obesity by inhibiting the expansion of adipose tissue and adipocyte hypertrophy, and improved hepatic steatosis by activating AMPKα to reduce hepatic fat accumulation. CTPG ameliorated HFD-induced hyperinsulinemia, hyperglycemia, inflammation and insulin resistance by activating IRS1/Akt/GLUT4 insulin signaling pathway in white adipose tissue. Moreover, gut microbiota structure and metabolic functions in HFD-induced obese mice was changed by CTPG, especially short chain fatty acids-producing bacteria including Blautia, Roseburia, Butyrivibrio and Bacteriodes were significantly increased by CTPG treatment.

Conclusions

CTPG effectively suppressed adipogenesis and lipid accumulation in 3T3-L1 adipocytes and ameliorated HFD-induced obesity and insulin resistance through activating AMPKα and IRS1/AKT/GLUT4 signaling pathway and regulating the composition and metabolic functions of gut microbiota.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03743-6.

Metagenomic insights into the modulatory effects of kelp powder (Thallus laminariae)-Treated dairy milk on growth performances and physiological lipometabolic processes of kunming mice

Kelp powder, supplemented with a dairy cow diet, effectively improved the milk polyunsaturated fatty acids (PUFAs) content. However, little information exists on the downstream effects of the kelp-treated milk on body health, gut microbiota, and nutrient metabolism. For this purpose, 48 3-week old Kunming (KM) male mice with an average body weight of 16.1 g ± 0.2 g were randomly divided into the control treatment (CON, fed with standard chow), the common milk supplement treatment (Milk), and the kelp powder-treated milk supplement treatment (KPM). The experiment lasted for 35 days, with a 7-day long adaptive period and a 28-day long main trial. Phenotypic parameters including growth performances and serum lipids-related parameters were first measured, and results indicated that Milk and KPM supplement significantly promoted the total body weight gain (P < 0.05), while significantly decreasing the feed conversion ratio compared with CON (P < 0.05). No significant differences were observed in the blood lipids content among all three treatments, however, the triglyceride content showed a decreasing trend after KPM supplement treatment. Further, activities of liver lipometabolic-related enzymes were investigated to determine the underlying factors that impacted physiological lipid metabolism. KPM treatment showed a significant reductive effect on the activity of lipogenesis-related enzymes, such as FAS and ACC, while a significant stimulative effect on the activity of lipolysis-related enzymes included the ATGL and CPT1 compared with CON (P < 0.05). Finally, gastrointestinal tract development and cecal microbiota community that correlated with body lipid degradation and absorption were measured to determine the underlying mechanism of KPM supplementation on physiological lipid metabolism. Results indicated that supplementation with KPM significantly enhanced cecal bacteria diversity which was reflected in the significant increase of Chao1 and ACE indexes. Besides, starch-degraded bacteria such as Faecalibacterium, Ruminococcaceae, and Streptococcus are significant decreased (P < 0.05), while cellulose-degraded bacteria including Parabacteroides, Prevotella, Lactobacillus, Clostridium, and Bifidobacterium are significantly increased (P < 0.05) after KPM supplement, which may further restrict the energy generation and therefore reduce the lipid deposition. In summary, kelp supplement helped increase the milk PUFAs content, enhance the bacterial diversity and relative abundances of probiotics, which finally modulated physiological lipid metabolism, and promote growth performances.

Replacing saturated fatty acids with polyunsaturated fatty acids increases the abundance of Lachnospiraceae and is associated with reduced total cholesterol levels-a randomized controlled trial in healthy individuals

Background

Improving dietary fat quality strongly affects serum cholesterol levels and hence the risk of cardiovascular diseases (CVDs). Recent studies have identified dietary fat as a potential modulator of the gut microbiota, a central regulator of host metabolism including lipid metabolism. We have previously shown a significant reduction in total cholesterol levels after replacing saturated fatty acids (SFAs) with polyunsaturated fatty acids (PUFAs). The aim of the present study was to investigate the effect of dietary fat quality on gut microbiota, short-chain fatty acids (SCFAs), and bile acids in healthy individuals. In addition, to investigate how changes in gut microbiota correlate with blood lipids, bile acids, and fatty acids.

Methods

Seventeen participants completed a randomized, controlled dietary crossover study. The participants received products with SFAs (control) or PUFAs in random order for three days. Fecal samples for gut microbiota analyses and fasting blood samples (lipids, fatty acids, and bile acids) were measured before and after the three-day intervention.

Results

Of a panel of 40 bacteria, Lachnospiraceae and Bifidobacterium spp. were significantly increased after intervention with PUFAs compared with SFAs. Interestingly, changes in Lachnospiraceae, as well as Phascolarlactobacterium sp. and Eubacterium hallii, was also found to be negatively correlated with changes in total cholesterol levels after replacing the intake of SFAs with PUFAs for three days. No significant differences in SCFAs or bile acids were found after the intervention.

Conclusion

Replacing SFAs with PUFAs increased the abundance of the gut microbiota family of Lachnospiraceae and Bifidobacterium spp. Furthermore, the reduction in total cholesterol after improving dietary fat quality correlated with changes in the gut microbiota family Lachnospiraceae. Future studies are needed to reveal whether Lachnospiraceae may be targeted to reduce total cholesterol levels.

Trial registration

The study was registered at Clinical Trials (https://clinicaltrials.gov/, registration identification number: NCT03658681).

Significantly different roles of economic affluence in sex-specific obesity prevalence rates: understanding more modifications within female body weight management

Socioeconomic status has been associated with obesity prevalence increase in both males and females worldwide. We examined the magnitude of the difference between the two relationships and explored the independence of both relationships. Country specific data on gross domestic product (GDP) per capita, sex-specific obesity prevalence rates, urbanisation, total calories availability and level of obesity, genetic background accumulation (measured by the Biological State Index, I_bs) were obtained for 191 countries. Curvilinear regressions, bivariate and partial correlations, linear mixed models and multivariate linear regression analyses were used to examine the relationship between GDP and obesity prevalence rates in males and females respectively. Fisher’s r-to-z transformation, F-test and R² increment in multivariate regression were used to compare results for males and females. GDP significantly correlated with sex-specific obesity prevalence rates, but significantly more strongly with male obesity prevalence in bivariate correlation analyses. These relationships remained independent of calories availability, I_bs and urbanization in partial correlation model. Stepwise multiple regression identified that GDP was a significant predictor of obesity prevalence in both sexes. Multivariate stepwise regression showed that, when adding GDP as an obesity prevalence predictor, the absolute increment of R² in male fit model (0.046) was almost four (4) times greater than the absolute increment in female model fit (0.012). The Stepwise analyses also revealed that 68.0% of male but only 37.4% of female obesity prevalence rates were explained by the total contributing effects of GDP, I_bs, urbanization and calories availability. In both Pearson’s r and nonparametric analyses, GDP contributes significantly more to male obesity than to female obesity in both developed and developing countries. GDP also determined the significant regional variation in male, but not female obesity prevalence. GDP may contribute to obesity prevalence significantly more in males than in females regardless of the confounding effects of I_bs, urbanization and calories. This may suggest that aetiologies for female obesity are much more complex than for males and more confounders should be included in the future studies when data are available.

Regulatory Effect of Isomaltodextrin on a High-Fat Diet Mouse Model with LPS-Induced Low-Grade Chronic Inflammation

This study aimed to identify the effects of isomaltodextrin (IMD) on sustaining the gut integrity and microbiota composition in a high-fat diet (HFD) with a lipopolysaccharide (LPS)-induced low-grade inflammation mouse model. The homeostasis of the immune response is important to reduce the risk of developing metabolic syndromes. The results of this study showed that pre-treatment of IMD at 5% (w/v) suppressed the concentration of endotoxin and pro-inflammatory mediators TNF-α, MCP-1, and IL-6 while increasing the adiponectin level in the plasma. Subsequently, IMD supplementation maintained the structural integrity and intestinal permeability by upregulating the tight junction protein expressions, leading to reducing D-mannitol concentration in the blood. In addition, dysbiosis was observed in mice induced by HFD plus LPS, suggesting that unhealthy dietary factors elicit metabolic endotoxemia and associated dysbiosis to impair the barrier function. However, IMD supplementation was shown to restore the microbial diversity, promote the growth of Bacteroides-Prevotella, and upregulate the related d-glucarate and d-galactarate degradation pathways, together demonstrating the benefits of IMD as a prebiotic able to promote energy homeostasis. Our results also showed that the blood lipid profile and glucose level in the low-grade inflammation mouse model were modulated by IMD. Moreover, IMD supplementation effectively prevented the metabolic disorder and modulated immune responses in inflamed white adipose tissues by inhibiting the macrophage infiltration and restoring the adiponectin, PPAR-γ, and IRS-1 expression. These findings provide strong evidence for IMD to be a potential prebiotic that acts to sustain a healthy gut microbiota composition and barrier function. By protecting against an unhealthy diet-impaired metabolic balance and maintaining immune homeostasis, IMD may affect the development of metabolic disorders.

Milk fat globule membrane supplementation to obese rats during pregnancy and lactation promotes neurodevelopment in offspring via modulating gut microbiota

Pre-pregnancy obesity and high-fat diet (HFD) during pregnancy and lactation are associated with neurodevelopmental delay in offspring. This study aimed to investigate whether milk fat globule membrane (MFGM) supplementation in obese dams could promote neurodevelopment in offspring. Obese female rats induced by HFD were supplemented with MFGM during pregnancy and lactation. Maternal HFD exposure significantly delayed the maturation of neurological reflexes and inhibited neurogenesis in offspring, which were significantly recovered by maternal MFGM supplementation. Gut microbiota analysis revealed that MFGM supplementation modulated the diversity and composition of gut microbiota in offspring. The abundance of pro-inflammatory bacteria such as Escherichia shigella and Enterococcus were down-regulated, and the abundance of bacteria with anti-inflammatory and anti-obesity functions, such as Akkermansia and Lactobacillus were up-regulated. Furthermore, MFGM alleviated neuroinflammation by decreasing the levels of lipopolysaccharides (LPS) and pro-inflammatory cytokines in the circulation and brain, as well as inhibiting the activation of microglia. Spearman’s correlation analysis suggested that there existed a correlation between gut microbiota and inflammation-related indexes. In conclusion, maternal MFGM supplementation promotes neurodevelopment partly via modulating gut microbiota in offspring.

Lack of Associations between Environmental Exposures and Environmental Enteric Dysfunction among 18-Month-Old Children in Rural Malawi

Environmental enteric dysfunction (EED) is common and contributes to linear growth faltering (stunting) and mortality among children in low-resource settings. A few studies on the environmental causes of EED have been conducted but the exact exposures that cause or predispose children to EED are context-specific and not clear. This study aimed to assess associations between selected environmental exposures and EED markers among 620 18-month-old children. This was a secondary analysis of data from Malawian children who participated in a randomized controlled trial (iLiNS-DYAD, registered at clinicaltrials.gov as NCT01239693) from birth to 18 months of age. Data on environmental exposures, including drinking water source, sanitation, exposure to animals, housing materials, season, residential area, and food insecurity were collected at enrolment. Biomarkers of EED included concentrations of calprotectin, regenerating 1B protein (REG1B), and alpha-1-antitrypsin from stool samples to assess intestinal inflammation, repair, and permeability, respectively. We performed bivariate and multivariable analyses to assess associations between environmental exposures and EED biomarkers. Adjusting for possible confounders, we did not find associations between the selected environmental exposures and the three biomarkers. These results do not provide support for our hypothesis that the studied adverse environmental exposures are associated with increased concentrations of children's EED markers in rural Malawi.

From the Ketogenic Diet to the Mediterranean Diet: The Potential Dietary Therapy in Patients with Obesity after CoVID-19 Infection (Post CoVID Syndrome)

PURPOSE OF REVIEW

This review primarily examines the evidence for areas of consensus and on-going uncertainty or controversy about diet and physical exercise approaches for in the post-CoVID. We propose an ideal dietary and physical activity approach that the patient with obesity should follow after CoVID-19 infection in order to reduce the clinical conditions associated with post-CoVID syndrome.

RECENT FINDINGS

The CoVID-19 disease pandemic, caused by the severe acute respiratory syndrome coronavirus-2, has spread all over the globe, infecting hundreds of millions of individuals and causing millions of death. It is also known to be is associated with several medical and psychological complications, especially in patients with obesity and weight-related disorders who in general pose a significant global public health problem, and in specific affected individuals are on a greater risk of developing poorer CoVID-19 clinical outcomes and experience a higher rate of mortality. Little is still known about the best nutritional approach to be adopted in this disease especially in the patients post-CoVID syndrome. To the best of our knowledge, no specific nutritional recommendations exist to manage in the patients post-CoVID syndrome. We report a presentation of nutritional therapeutic approach based on a ketogenic diet protocol followed by a transition to the Mediterranean diet in patients post-infection by CoVID, combined to a physical activity program to address conditions associated with post-CoVID syndrome.

Paradigm Shift in Phytochemicals Research: Evolution from Antioxidant Capacity to Anti-Inflammatory Effect and to Roles in Gut Health and Metabolic Syndrome

Food bioactive components, particularly phytochemicals with antioxidant capacity, have been extensively studied over the past two decades. However, as new analytical and molecular biological tools advance, antioxidants related research has undergone significant paradigm shifts. This review is a high-level overview of the evolution of phytochemical antioxidants research. Early research used chemical models to assess the antioxidant capacity of different phytochemicals, which provided important information about the health potential, but the results were overused and misinterpreted despite the lack of biological relevance (Antioxidants v1.0). This led to findings in the anti-inflammatory properties and modulatory effects of cell signaling of phytochemicals (Antioxidants v2.0). Recent advances in the role of diet in modulating gut microbiota have suggested a new phase of food bioactives research along the phytochemicals-gut microbiota-intestinal metabolites-low-grade inflammation-metabolic syndrome axis (Antioxidants v3.0). Polyphenols and carotenoids were discussed in-depth, and future research directions were also provided.