Food emulsifier polysorbate 80 promotes the intestinal absorption of mono-2-ethylhexyl phthalate by disturbing intestinal barrier

Co-exposure to boscalid and amoxicillin inhibited the degradation of boscalid and aggravated the threat to the earthworm

The extensive application of pesticides and antibiotics in agricultural production makes it possible for them to coexist in farmland, and the interaction of the two pollutants can lead to changes in environmental behavior and toxicity, creating uncertainty risks to soil and soil organisms. In this study, we explored the environmental behavior and the effects of earthworms under co-exposure to amoxicillin and boscalid and further explored the accumulation and toxic effects on earthworms. The results showed that amoxicillin increased the adsorption of boscalid in soil and inhibited its degradation. In addition, we noticed that the co-exposure of amoxicillin and boscalid caused intestinal barrier damage, which increased the bioaccumulation of earthworms for boscalid and led to more severe oxidative stress and metabolic disorders in earthworms. In summary, our findings indicate that amoxicillin can increase the ecological risk of boscalid in the environment and imply that the encounter between antibiotics and pesticides in the environment can amplify the toxic effects of pesticides, which provides new insights into the ecological risks of antibiotics.

Food emulsifiers aggravate inflammation and oxidative stress induced by food contaminants in zebrafish

Food emulsifiers like glycerol monostearate (G) and Tween 80 (TW) are commonly used to help formation and maintain stability of emulsions. However, certain food contaminants and emulsifiers often co-occur in the same food item due to food culture and cooking methods. For this reason, the present study investigated interaction of toxic effect of emulsifiers (G and TW) and process contaminants (acrylamide (AA) and benzo [a]pyrene (BAP)) on zebrafish. Adult zebrafish were exposed to emulsifiers, food contaminants, or the combination through diet for 2 h and 7 days. Oxidative stress and inflammation caused by food contaminants were increased when food emulsifiers were present. These combined treatments also induced more severe morphological changes than the contaminant alone treatments. In the gut, disruption of villi structure and increased number of goblet cells was observed and in the liver there were increased lipid deposition, infiltration of immune cells, glycogen depletion and focal necrosis. Increased accumulation of AA and BAP in the liver and gut were detected after addition of emulsifiers, suggesting that emulsifiers can enhance absorption of diet-borne contaminants. Our results showed food emulsifiers and contaminants can interact synergistically and increase risk.

Food emulsifiers increase toxicity of food contaminants in three human GI tract cell lines

Food products simultaneously containing both food contaminants and emulsifiers are common in baked products, coffee and chocolate. Little is known regarding how food contaminants and emulsifiers interact and alter toxicity. Recent studies have shown that while emulsifiers themselves have little toxicity, they could cause changes in the gut microenvironment and lead to issues such as increased uptake of allergens. This study examined toxic effect of two common process contaminants acrylamide (AA) and benzo [a]pyrene (BAP) combined with food emulsifiers polyoxyethylene sorbitan monooleate (TW) or glycerol monostearate (G). In liver cell line HepG2 and gastrointestinal cell lines HIEC6 and Caco-2, toxicities of AA and BAP were increased by TW but not by G as indicated by decrease in IC50 values. Addition of TW also exacerbated gene expression changes caused by AA or BAP. Cellular uptake and cell membrane permeability were enhanced by TW but not by G, but tight junction proteins of Caco-2 monolayer was impacted by both emulsifiers. These results suggested that TW could increase toxicity of AA and BAP through increasing cell permeability thus chemical uptake and potentially through other interactions. The study is to draw the attention of regulators on the potential synergistic interaction of co-occurring chemicals in food.

Food additive emulsifiers and cancer risk: Results from the French prospective NutriNet-Santé cohort

BACKGROUND

Emulsifiers are widely used food additives in industrially processed foods to improve texture and enhance shelf-life. Experimental research suggests deleterious effects of emulsifiers on the intestinal microbiota and the metabolome, leading to chronic inflammation and increasing susceptibility to carcinogenesis. However, human epidemiological evidence investigating their association with cancer is nonexistent. This study aimed to assess associations between food additive emulsifiers and cancer risk in a large population-based prospective cohort.

METHODS AND FINDINGS

This study included 92,000 adults of the French NutriNet-Santé cohort without prevalent cancer at enrolment (44.5 y [SD: 14.5], 78.8% female, 2009 to 2021). They were followed for an average of 6.7 years [SD: 2.2]. Food additive emulsifier intakes were estimated for participants who provided at least 3 repeated 24-h dietary records linked to comprehensive, brand-specific food composition databases on food additives. Multivariable Cox regressions were conducted to estimate associations between emulsifiers and cancer incidence. Overall, 2,604 incident cancer cases were diagnosed during follow-up (including 750 breast, 322 prostate, and 207 colorectal cancers). Higher intakes of mono- and diglycerides of fatty acids (FAs) (E471) were associated with higher risks of overall cancer (HR high vs. low category = 1.15; 95% CI [1.04, 1.27], p-trend = 0.01), breast cancer (HR = 1.24; 95% CI [1.03, 1.51], p-trend = 0.04), and prostate cancer (HR = 1.46; 95% CI [1.09, 1.97], p-trend = 0.02). In addition, associations with breast cancer risk were observed for higher intakes of total carrageenans (E407 and E407a) (HR = 1.32; 95% CI [1.09, 1.60], p-trend = 0.009) and carrageenan (E407) (HR = 1.28; 95% CI [1.06, 1.56], p-trend = 0.01). No association was detected between any of the emulsifiers and colorectal cancer risk. Several associations with other emulsifiers were observed but were not robust throughout sensitivity analyses. Main limitations include possible exposure measurement errors in emulsifiers intake and potential residual confounding linked to the observational design.

CONCLUSIONS

In this large prospective cohort, we observed associations between higher intakes of carrageenans and mono- and diglycerides of fatty acids with overall, breast and prostate cancer risk. These results need replication in other populations. They provide new epidemiological evidence on the role of emulsifiers in cancer risk.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03335644.

Subchronic exposure to di-(2-ethylhexyl) phthalate (DEHP) elicits blood-brain barrier dysfunction and neuroinflammation in male C57BL/6J mice

BACKGROUND

Exposure to di-(2-ethylhexyl) phthalate (DEHP) can cause neurotoxicity but the mechanism is not clear. Blood brain barrier (BBB) is one of the most important tissues to protect the brain. However, whether DEHP can disrupt the BBB or not remains unclear. The objective of this study is to investigate the potential effects of subchronic DEHP exposure on BBB integrity and discuss the role of BBB in DEHP inducible neurotoxicity with an emphasis on neuroinflammatory responses. Male adult C57BL/6J mice were orally administered with vehicle or 200 or 750 mg/kg/day DEHP for 90 days. Subchronic exposure to high-dose DEHP increased water intake but decreased body weight and brain weight. The concentrations of DEHP metabolites increased in serum from all DEHP-exposed groups while increased in brain only from the high-dose group. DEHP induced neurobehavioural alterations and damaged hippocampal neurons. DEHP increased BBB permeability by Evans blue (EB) extravasation and decreased tight junction proteins (ZO-1, occludin, and claudin-5) while presenting a neuroinflammatory feature characterized by the upregulated inflammatory mediators TNF-α and the NLRP3/caspase-1/IL-1β inflammasome pathway. Our data provide new insights into neurotoxicity caused by subchronic DEHP exposure, which is probably involved in BBB dysfunction and neuroinflammatory responses.

Safety of surfactant excipients in oral drug formulations

Surfactants are a diverse group of compounds that share the capacity to adsorb at the boundary between distinct phases of matter. They are used as pharmaceutical excipients, food additives, emulsifiers in cosmetics, and as household/industrial detergents. This review outlines the interaction of surfactant-type excipients present in oral pharmaceutical dosage forms with the intestinal epithelium of the gastrointestinal (GI) tract. Many surfactants permitted for human consumption in oral products reduce intestinal epithelial cell viability in vitro and alter barrier integrity in epithelial cell monolayers, isolated GI tissue mucosae, and in animal models. This suggests a degree of mis-match for predicting safety issues in humans from such models. Recent controversial preclinical research also infers that some widely used emulsifiers used in oral products may be linked to ulcerative colitis, some metabolic disorders, and cancers. We review a wide range of surfactant excipients in oral dosage forms regarding their interactions with the GI tract. Safety data is reviewed across in vitro, ex vivo, pre-clinical animal, and human studies. The factors that may mitigate against some of the potentially abrasive effects of surfactants on GI epithelia observed in pre-clinical studies are summarised. We conclude with a perspective on the overall safety of surfactants in oral pharmaceutical dosage forms, which has relevance for delivery system development.

Effect of altered human exposome on the skin and mucosal epithelial barrier integrity

Pollution in the world and exposure of humans and nature to toxic substances is continuously worsening at a rapid pace. In the last 60 years, human and domestic animal health has been challenged by continuous exposure to toxic substances and pollutants because of uncontrolled growth, modernization, and industrialization. More than 350,000 new chemicals have been introduced to our lives, mostly without any reasonable control of their health effects and toxicity. A plethora of studies show exposure to these harmful substances during this period with their implications on the skin and mucosal epithelial barrier and increasing prevalence of allergic and autoimmune diseases in the context of the "epithelial barrier hypothesis". Exposure to these substances causes an epithelial injury with peri-epithelial inflammation, microbial dysbiosis and bacterial translocation to sub-epithelial areas, and immune response to dysbiotic bacteria. Here, we provide scientific evidence on the altered human exposome and its impact on epithelial barriers.

Mechanisms of gut epithelial barrier impairment caused by food emulsifiers polysorbate 20 and polysorbate 80

BACKGROUND

The rising prevalence of many chronic diseases related to gut barrier dysfunction coincides with the increased global usage of dietary emulsifiers in recent decades. We therefore investigated the effect of the frequently used food emulsifiers on cytotoxicity, barrier function, transcriptome alterations, and protein expression in gastrointestinal epithelial cells.

METHODS

Human intestinal organoids originating from induced pluripotent stem cells, colon organoid organ-on-a-chip, and liquid-liquid interface cells were cultured in the presence of two common emulsifiers: polysorbate 20 (P20) and polysorbate 80 (P80). The cytotoxicity, transepithelial electrical resistance (TEER), and paracellular-flux were measured. Immunofluorescence staining of epithelial tight-junctions (TJ), RNA-seq transcriptome, and targeted proteomics were performed.

RESULTS

Cells showed lysis in response to P20 and P80 exposure starting at a 0.1% (v/v) concentration across all models. Epithelial barrier disruption correlated with decreased TEER, increased paracellular-flux and irregular TJ immunostaining. RNA-seq and targeted proteomics analyses demonstrated upregulation of cell development, signaling, proliferation, apoptosis, inflammatory response, and response to stress at 0.05%, a concentration lower than direct cell toxicity. A proinflammatory response was characterized by the secretion of several cytokines and chemokines, interaction with their receptors, and PI3K-Akt and MAPK signaling pathways. CXCL5, CXCL10, and VEGFA were upregulated in response to P20 and CXCL1, CXCL8 (IL-8), CXCL10, LIF in response to P80.

CONCLUSIONS

The present study provides direct evidence on the detrimental effects of food emulsifiers P20 and P80 on intestinal epithelial integrity. The underlying mechanism of epithelial barrier disruption was cell death at concentrations between 1% and 0.1%. Even at concentrations lower than 0.1%, these polysorbates induced a proinflammatory response suggesting a detrimental effect on gastrointestinal health.

Endocrine-Disrupting Chemicals and Disease Endpoints

Endocrine-disrupting chemicals (EDCs) have significant impacts on biological systems, and have been shown to interfere with physiological systems, especially by disrupting the hormone balance. During the last few decades, EDCs have been shown to affect reproductive, neurological, and metabolic development and function and even stimulate tumor growth. EDC exposure during development can disrupt normal development patterns and alter susceptibility to disease. Many chemicals have endocrine-disrupting properties, including bisphenol A, organochlorines, polybrominated flame retardants, alkylphenols, and phthalates. These compounds have gradually been elucidated as risk factors for many diseases, such as reproductive, neural, and metabolic diseases and cancers. Endocrine disruption has been spread to wildlife and species that are connected to the food chains. Dietary uptake represents an important source of EDC exposure. Although EDCs represent a significant public health concern, the relationship and specific mechanism between EDCs and diseases remain unclear. This review focuses on the disease-EDC relationship and the disease endpoints associated with endocrine disruption for a better understanding of the relationship between EDCs-disease and elucidates the development of new prevention/treatment opportunities and screening methods.

Beyond allergic progression: From molecules to microbes as barrier modulators in the gut-lung axis functionality

The "epithelial barrier hypothesis" states that a barrier dysfunction can result in allergy development due to tolerance breakdown. This barrier alteration may come from the direct contact of epithelial and immune cells with the allergens, and indirectly, through deleterious effects caused by environmental changes triggered by industrialization, pollution, and changes in the lifestyle. Apart from their protective role, epithelial cells can respond to external factors secreting IL-25 IL-33, and TSLP, provoking the activation of ILC2 cells and a Th2-biased response. Several environmental agents that influence epithelial barrier function, such as allergenic proteases, food additives or certain xenobiotics are reviewed in this paper. In addition, dietary factors that influence the allergenic response in a positive or negative way will be also described here. Finally, we discuss how the gut microbiota, its composition, and microbe-derived metabolites, such as short-chain fatty acids, alter not only the gut but also the integrity of distant epithelial barriers, focusing this review on the gut-lung axis.

Food Emulsifiers and Metabolic Syndrome: The Role of the Gut Microbiota

The use of emulsifiers in processed foods and the rapid epidemic development of metabolic syndrome in Western countries over the past 20 years have generated growing interest. Evidence for the role of emulsifiers in metabolic syndrome through gut microbiota has not been clearly established, thus making it challenging for clinical nutritionists and dietitians to make evidence-based associations between the nature and the quantity of emulsifiers and metabolic disorders. This narrative review summarizes the highest quality clinical evidence currently available about the impact of food emulsifiers on gut microbiota composition and functions and the potential development of metabolic syndrome. The state-of-the-art of the different common emulsifiers is performed, highlighting where they are present in daily foods and their roles. Recent findings of in vitro, in vivo, and human studies assessing the effect of different emulsifiers on gut microbiota have been recently published. There is some progress in understanding how some food emulsifiers could contribute to developing metabolic diseases through gut microbiota alterations while others could have prebiotic effects. However, there are still many unanswered questions regarding daily consumption amounts and the synergic effects between emulsifiers’ intake and responses by the microbial signatures of each individual.

SEDDS facilitate cinnamaldehyde crossing the mucus barrier: The perspective of mucus and Caco-2/HT29 co-culture models

Self-emulsifying drug delivery systems (SEDDS) have potential applications in the delivery of hydrophobic components. Oral drugs are readily captured and cleared by intestinal mucus, a natural barrier that covers the mucosal epithelium and prevents the entry of foreign substances. In this study, we investigated for the first time the ability of SEDDS to deliver the lipophilic aldehyde cinnamaldehyde (CA-SEDDS) in rat mucus, mucin solution, Caco-2 and Caco-2/HT29 co-culture monolayer systems. CA-SEDDS was characterized by particle size, Zeta potential and the logD_{SEDDS/release medium}. The capacity of CA-SEDDS to enhance mucus permeability was investigated in rat intestinal mucus gel and mucin solution with the period of in 12 h by Transwell® diffusion. We evaluated the potential of CA-SEDDS delivery of CA in a co-culture system of absorptive Caco-2 and mucus-secreting HT29 cells. CA-SEDDS exhibited excellent mucus permeability in mucus and mucin solutions, 5.1- and 2.8-fold higher than the free CA group, respectively. CA-SEDDS penetration increased by 2.5-fold compared with free CA when using the mucus-secreting co-culture cell model as a barrier. The relative oral bioavailability of CA-SEDDS was 242% compared to CA without formulation. These findings suggest that SEDDS exhibited good release and superior mucus permeability, displaying great potential for the future of hydrophobic oral applications.

Toxicokinetics of mono-(2-ethylhexyl) phthalate with low-dose exposure applying fluorescence tracing technique

Di(2-ethylhexyl) phthalate (DEHP) belongs to environmental endocrine disrupting chemicals (EEDCs) and can be rapidly hydrolyzed into the ultimate toxicant mono-2-ethylhexyl phthalate (MEHP). In this study, we used 5-aminofluorescein modified MEHP (MEHP-AF) as a fluorescence tracer to explore the toxicokinetics, including toxicokinetic parameters, absorption and transport across the intestinal mucosal barrier, distribution and pathological changes of organs. While the dose was as lower than 10 mg/kg by intragastric administration, the toxicokinetic parameters obtained by fluorescence microplate method were similar to those with the literatures by chromatography. MEHP-AF can be rapidly absorbed through the intestinal mucosal barrier in rats. In situ organ distribution in mice showed that MEHP-AF was mainly concentrated in the liver, kidney and testis. Our results suggested that the fluorescence tracing technique had the advantages with easy processing, less time-consuming, higher sensitivity for the quantitative determination, In addition, this technology also avoids the interference of exogenous or endogenous DEHP and MEHP in the experimental system. It also can be utilized to the visualization detection of MEHP in situ localization in the absorption organ and the toxic target organ. The results show that this may be a more feasible MEHP toxicological research method.

Effects of Docetaxel Injection and Docetaxel Micelles on the Intestinal Barrier and Intestinal Microbiota

Increasing evidence has suggested that chemotherapeutics affect the integrity of the intestinal barrier and alter the intestinal microbiota, thus limiting the therapeutic outcomes of cancer chemotherapy. Docetaxel (DTX) is used for breast cancer treatment and has gastrointestinal side effects, but the influence of DTX formulations on the intestinal barrier and intestinal microbiota remains unknown. Therefore, in this work, the influence of DTX injection (free DTX, commercial formulation) and DTX/methoxy poly(ethylene glycol)-block-poly(D,L-lactide) (mPEG-PDLLA) (DTX micelles, nanoformulation) on the integrity of the intestinal barrier and the intestinal microbiota is investigated. It is found that the free DTX causes significantly greater intestinal barrier damage than the DTX micelles. The diversity of the intestinal microbiota, and the relative abundance of Akkermansia muciniphila and Ruminococcus gnavus in the DTX micelle-treated group is significantly higher than that in the free DTX-treated group. Moreover, the tumor growth rate is elevated in antibiotic mixture-pretreated mice, demonstrating that the diversity and composition of the intestinal microbiota may be associated with tumor progression. This work demonstrates that different formulations of chemotherapeutics have different effects on the integrity of the intestinal barrier and the intestinal microbiota.

Transient Permeation Enhancer® (TPE®) technology for oral delivery of octreotide: a technological evaluation

INTRODUCTION

The FDA approval of oral semaglutide for type 2 diabetes (2019) and oral octreotide for acromegaly (2020) is evidence that selected niche peptides can be administered orally if formulated with selected intestinal permeation enhancers.

AREAS COVERED

We evaluated the oral octreotide formulation, MYCAPSSA® (Chiasma Pharmaceuticals, Needham, MA, USA). An outline of the current standard of care in acromegaly and the benefits of oral octreotide versus depot injections is provided. We discuss the Transient Permeation Enhancer (TPE®) technology used and detail the safety and efficacy data from animal models and clinical trials.

EXPERT OPINION

TPE® is an oily suspension of octreotide that includes a number of excipients that can transiently alter epithelial barrier integrity by opening of intestinal epithelial tight junctions arising from transcellular perturbation. Phase I studies using 20 mg octreotide capsules yielded a relative oral bioavailability of ~0.7% and primary endpoints were achieved in two Phase III studies. The oral octreotide dose required to achieve these endpoints was over 200 times that of the 0.1 mg immediate-release subcutaneous injection, a reminder of the difficulty in achieving oral absorption of macromolecules. Many acromegaly patients will prefer a convenient twice-daily oral formulation of octreotide compared to monthly depot injections.