Endotoxemia is modulated by quantity and quality of dietary fat in older adults

The Role of Diet, Additives, and Antibiotics in Metabolic Endotoxemia and Chronic Diseases

Background/Objectives: Dietary patterns, including high-fat and high-carbohydrate diets (HFDs and HCDs), as well as non-dietary factors such as food additives and antibiotics, are strongly linked to metabolic endotoxemia, a critical driver of low-grade chronic inflammation. This review explores the mechanisms through which these factors impair intestinal permeability, disrupt gut microbial balance, and facilitate lipopolysaccharide (LPS) translocation into the bloodstream, contributing to metabolic disorders such as obesity, type 2 diabetes mellitus, and inflammatory bowel disease. Methods: The analysis integrates findings from recent studies on the effects of dietary components and gut microbiota interactions on intestinal barrier function and systemic inflammation. Focus is given to experimental designs assessing gut permeability using biochemical and histological methods, alongside microbiota profiling in both human and animal models. Results: HFDs and HCDs were shown to increase intestinal permeability and systemic LPS levels, inducing gut dysbiosis and compromising barrier integrity. The resulting endotoxemia promoted a state of chronic inflammation, disrupting metabolic regulation and contributing to the pathogenesis of various metabolic diseases. Food additives and antibiotics further exacerbated these effects by altering microbial composition and increasing gut permeability. Conclusions: Diet-induced alterations in gut microbiota and barrier dysfunction emerge as key mediators of metabolic endotoxemia and related disorders. Addressing dietary patterns and their impact on gut health is crucial for developing targeted interventions. Further research is warranted to standardize methodologies and elucidate mechanisms for translating these findings into clinical applications.

Regulation of endotoxemia through the gut microbiota: The role of the Mediterranean diet and its components

Endotoxemia is closely related to many diseases. As the largest endotoxin reservoir in the human body, the gut microbiota should be a key target for alleviating endotoxemia. The intestinal microbiota is believed to cause endotoxemia directly or indirectly by modifying the intestinal barrier function through dysbiosis, changing intestinal mucosal permeability and bacterial translocation. Diet is known to be the main environmental factor affecting the intestinal microbiota, and different diets and food components have a large impact on the gut microbiota. The Mediterranean diet, which received much attention in recent years, is believed to be able to regulate the gut microbiota, thereby maintaining the function of the intestinal barrier and alleviating endotoxemia. In this review, we focus on the relationship between the gut microbiota and endotoxemia, and how the Mediterranean dietary (MD) pattern can interfere with endotoxemia through the gut microbiota.

Association between dietary patterns and cardiovascular diseases: A review

Cardiovascular disease (CVD), especially atherosclerosis, is the primary cause of global deaths. It accounts for millions of deaths annually. Even a small reduction in CVD through preventive treatment can have a substantial impact. Dietary patterns and substances are strongly linked to chronic diseases such as atherosclerosis, hypertension, heart failure, and type 2 diabetes. An unhealthy diet could lead to traditional risk factors such as LDL levels, TG levels, diabetes, and high blood pressure while accelerating atherosclerosis progression. Recent research has shown the potential of dietary interventions to prevent and treat cardiovascular disease, particularly through healthy dietary patterns such as the Mediterranean diet or DASH. In 2016, the World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC) launched a new initiative aimed at enhancing the prevention and control of cardiovascular disease (CVD) by improving the management of CVD in primary care, including the optimization of dietary patterns. Here, this review summarizes several large cohort researches about the effects of dietary patterns on atherosclerosis, refines dietary components, and outlines some typical anti-atherosclerosis dietary agents. Finally, this review discusses recent mechanisms by which dietary interventions affect atherosclerosis progression.

Treatment of Dyslipidemia through Targeted Therapy of Gut Microbiota

Dyslipidemia is a multifaceted condition with various genetic and environmental factors contributing to its pathogenesis. Further, this condition represents an important risk factor for its related sequalae including cardiovascular diseases (CVD) such as coronary artery disease (CAD) and stroke. Emerging evidence has shown that gut microbiota and their metabolites can worsen or protect against the development of dyslipidemia. Although there are currently numerous treatment modalities available including lifestyle modification and pharmacologic interventions, there has been promising research on dyslipidemia that involves the benefits of modulating gut microbiota in treating alterations in lipid metabolism. In this review, we examine the relationship between gut microbiota and dyslipidemia, the impact of gut microbiota metabolites on the development of dyslipidemia, and the current research on dietary interventions, prebiotics, probiotics, synbiotics and microbiota transplant as therapeutic modalities in prevention of cardiovascular disease. Overall, understanding the mechanisms by which gut microbiota and their metabolites affect dyslipidemia progression will help develop more precise therapeutic targets to optimize lipid metabolism.

Anti-Inflammatory Properties of Diet: Role in Healthy Aging

Inflammation is a physiological process involved in the defenses of the body and the repair of tissues. It is acutely activated by infections, trauma, toxins, or allergic reactions. However, if it becomes chronic, inflammation can end up stimulating the development of diseases such as cardiovascular disease, autoimmune disease, neurological disease, or cancer. Additionally, during aging, inflammation becomes increasingly more chronic. Furthermore, we found that certain foods, such as saturated fats, have pro-inflammatory activity. Taking this into account, in this review we have discussed different diets with possible anti-inflammatory activity, the commonly ingested components of each diet and their active compounds. In addition, we have proposed some dietary guidelines, as well as a list of compounds present in foods with anti-inflammatory activity, outlining how to combine them to achieve optimal anti-inflammatory effects. Therefore, we can conclude that the compounds in our diet with anti-inflammatory activity could help alleviate the inflammatory processes derived from diseases and unhealthy diets, and thereby promote healthy aging.

Effects of dietary fat quality on metabolic endotoxaemia: a systematic review

In this systematic review, we critically evaluated human clinical trials that assessed the effects of dietary fat quality on metabolic endotoxaemia. The studies were selected from three databases (PubMed, Scopus and Cochrane Library), and the keywords were defined according to the Medical Subject Headings indexing terminology. Two authors searched independently, according to the pre-defined selection criteria. Quality and risk assessment of bias for each selected study were also evaluated. The results of the included studies demonstrated associations between higher SFA intake and increased postprandial lipopolysaccharide (LPS) concentrations. On the other hand, after the consumption of PUFA, bloodstream LPS concentrations were lower. However, in none of the long-term studies, the consumption of dietary fats did not seem to exert effects on LPS concentration. Hence, SFA seem to act as a risk factor for transient increase in endotoxaemia, while PUFA demonstrated exerting a protective effect. Taken together, the evidence suggests that the dietary fatty acid profile may influence bloodstream endotoxin concentrations through modulation of factors such LPS clearance, alkaline phosphatase activity, bile acid metabolism, intestinal permeability and intestinal microbiota composition.

Metabolic Endotoxemia, Feeding Studies and the Use of the Limulus Amebocyte (LAL) Assay; Is It Fit for Purpose?

The Limulus amebocyte assay (LAL) is increasingly used to quantify metabolic endotoxemia (ME), particularly in feeding studies. However, the assay was not intended to assess plasma at levels typically seen in ME. We aimed to optimize and validate the LAL assay under a range of pre-treatment conditions against the well-established lipopolysaccharide binding protein assay (LBP). Fifteen healthy overweight and obese males aged 28.8 ± 9.1years provided plasma. The LAL assay employed a range of pre-treatments; 70 °C for 15 and 30 min and 80 °C for 15 and 30 min, ultrasonication (70 °C for 10 min and then 40 °C for 10 min), and dilution (1:50, 1:75, 1:100, and 1:200 parts) or diluted using 0.5% pyrosperse. Seventeen different plasma pre-treatment methods employed prior to the use of the LAL analytical technique failed to show any relationships with either LBP, or body mass index (BMI; obesity), the biological trigger for ME (p > 0.05 for all). As expected, BMI positively correlated with LBP (r = 0.523, p = 0.052. No relationships were observed between LAL with any of the sample pre-treatments and LBP or BMI. In its current form, the LAL assay is unsuitable for detecting levels of endotoxin typically seen in ME.

Poor Adherence to Mediterranean Diet and Serum Lipopolysaccharide are Associated with Oxidative Stress in Patients with Non-Alcoholic Fatty Liver Disease

Oxidative stress plays a pivotal role in non-alcoholic fatty liver disease (NAFLD). Factors inducing oxidative stress in NAFLD may be several; however, a relationship with the adherence to Mediterranean Diet (Med-diet) and with serum lipopolysaccharide (LPS) has been poorly investigated in this setting. The aim was to investigate factors associated with impaired oxidative stress in NAFLD, focusing on the potential role of LPS and Med-diet. We enrolled 238 consecutive outpatients from the PLINIO study, in whom we measured the soluble Nox2-derived peptide (sNox2-dp), a marker of systemic oxidative stress, and serum LPS. Adherence to Med-diet was investigated by a nine-item validated dietary questionnaire. Serum sNox2-dp and LPS were higher in patients with NAFLD compared to those without (25.0 vs. 9.0 pg/mL, p < 0.001 and 62.0 vs. 44.9 pg/mL, p < 0.001, respectively). In patients with NAFLD, the highest sNox2-dp tertile was associated with the top serum LPS tertile (Odds Ratio (OR): 4.71; p < 0.001), APRI > 0.7 (OR: 6.96; p = 0.005) and Med-diet-score > 6 (OR: 0.14; p = 0.026). Analyzing individual foods, the daily consumption of wine (OR: 0.29, p = 0.046) and the adequate weekly consumption of fish (OR: 0.32, p = 0.030) inversely correlated with the top sNox2-dp tertile. In conclusion, patients with NAFLD showed impaired oxidative stress. Levels of sNox2 correlated with serum LPS and with low adherence to Med-Diet.

Dietary Fatty Acids and Microbiota-Brain Communication in Neuropsychiatric Diseases

The gut-brain axis is a multimodal communication system along which immune, metabolic, autonomic, endocrine and enteric nervous signals can shape host physiology and determine liability, development and progression of a vast number of human diseases. Here, we broadly discussed the current knowledge about the either beneficial or deleterious impact of dietary fatty acids on microbiota-brain communication (MBC), and the multiple mechanisms by which different types of lipids can modify gut microbial ecosystem and contribute to the pathophysiology of major neuropsychiatric diseases (NPDs), such as schizophrenia (SCZ), depression and autism spectrum disorders (ASD).

Metabolic Endotoxemia: A Potential Underlying Mechanism of the Relationship between Dietary Fat Intake and Risk for Cognitive Impairments in Humans?

(1) Background: Nutrition is a major lifestyle factor that can prevent the risk of cognitive impairment and dementia. Diet-induced metabolic endotoxemia has been proposed as a major root cause of inflammation and these pathways emerge as detrimental factors of healthy ageing. The aim of this paper was to update research focusing on the relationship between a fat-rich diet and endotoxemia, and to discuss the potential role of endotoxemia in cognitive performances. (2) Methods: We conducted a non-systematic literature review based on the PubMed database related to fat-rich meals, metabolic endotoxemia and cognitive disorders including dementia in humans. A total of 40 articles out of 942 in the first screening met the inclusion criteria. (3) Results: Evidence suggested that a fat-rich diet, depending on its quality, quantity and concomitant healthy food components, could influence metabolic endotoxemia. Since only heterogeneous cross-sectional studies are available, it remains unclear to what extent endotoxemia could be associated or not with cognitive disorders and dementia. (4) Conclusions: A fat-rich diet has the capability to provide significant increases in circulating endotoxins, which highlights nutritional strategies as a promising area for future research on inflammatory-associated diseases. The role of endotoxemia in cognitive disorders and dementia remains unclear and deserves further investigation.

The relationship between vitamin C status, the gut-liver axis, and metabolic syndrome

Metabolic syndrome (MetS) is a constellation of cardiometabolic risk factors, which together predict increased risk of more serious chronic diseases. We propose that one consequence of dietary overnutrition is increased abundance of Gram-negative bacteria in the gut that cause increased inflammation, impaired gut function, and endotoxemia that further dysregulate the already compromised antioxidant vitamin status in MetS. This discussion is timely because "healthy" individuals are no longer the societal norm and specialized dietary requirements are needed for the growing prevalence of MetS. Further, these lines of evidence provide the foundational basis for investigation that poor vitamin C status promotes endotoxemia, leading to metabolic dysfunction that impairs vitamin E trafficking through a mechanism involving the gut-liver axis. This report will establish a critical need for translational research aimed at validating therapeutic approaches to manage endotoxemia-an early, but inflammation-inducing phenomenon, which not only occurs in MetS, but is also prognostic of more advanced metabolic disorders including type 2 diabetes mellitus, as well as the increasing severity of nonalcoholic fatty liver diseases.

Motivational Interviewing and Fat Consumption in Older Adults: A Meta-Analysis

Diets high in fat increase the risks for obesity and chronic diseases, even for older adults, the largest growing population in the United States. In the current study, a meta-analysis was performed to examine the effects of motivational interviewing (MI) dietary interventions on fat consumption in older adults. Electronic databases, journals, and unpublished literature were searched. Six primary studies were retrieved, providing seven comparisons between intervention and control groups and a total of 1,351 participants. MI had a moderate effect on fat intake in older adults (effect size = 0.354, p < 0.01). Studies with indicators of higher design quality showed greater MI effects. Nurses and providers can incorporate MI into health education and counseling to improve older adults' dietary health behaviors. [Journal of Gerontological Nursing, 44(11), 33-43.].

Metabolic status is related to the effects of adding of sacha inchi (Plukenetia volubilis L.) oil on postprandial inflammation and lipid profile: Randomized, crossover clinical trial

Sacha inchi oil (SIO) is an attractive source of polyunsaturated acids oil. A randomized crossover clinical trial was done to evaluate SIO effects on postprandial lipids and inflammatory state caused by a high-fat intake. Twenty metabolically healthy (MH) and 22 metabolically unhealthy (MU) subjects consumed a high-fat breakfast alone or supplemented with SIO. The biomarkers were measured in serum upon fasting, and after 1 and 4 hrs after breakfast. Interleukin-6 (IL-6) expression was determined in mononuclear cells. In the MH group, SIO reversed the cholesterol increase [iAUC_HFM : 0.27 mmol/L/4 h (IQR: -0.07/0.81); iAUC_HFM+S : -0.18 mmol/L/4 h (IQR: -0.49/0.31) p = 0.037] and decreased interleukin-6 concentration. In MU group, SIO attenuated lipopolysaccharides increase and interleukin-6 expression [(FC_HFM  = -1.19 (IQR: -1.72/1.93) and FC_HFM+S  = -1.83 (IQR: -4,82/-0.01), p = 0.017]. The effects of a high-fat meal on postprandial lipids and inflammation could be modified by the addition of SIO, but the outcomes are depending on the metabolic individual status. PRACTICAL APPLICATIONS: The seeds of Plukenetia volubilis L., also known as Sacha inchi, Sacha peanut or Inca peanut are an attractive vegetable source of oil which includes a high content of polyunsaturated fatty acids. Furthermore, the intake of Sacha inchi oil could improve the postprandial responses of a high-fat intake, and could be able to help to prevent cardiovascular diseases. Our results contribute to know the effects of this oil on postprandial inflammation and lipids. In addition, establishing how a person's basal metabolic status can determinate the metabolic response to this oil can help improve its use, and our results add evidence about the role of nutrition and diet in health and disease. At this time, the cultivation of Sacha inchi is being proposed as an agro-industrial alternative for the improvement of quality of living in Colombian rural areas.