In vitro colonic fermentation of a plant sterol-enriched beverage in a dynamic-colonic gastrointestinal digester

Ethylcoprostanol modulates colorectal cancer cell proliferation and mitigates cytotoxicity of cholesterol metabolites in non-tumor colon cells

Sterols can be metabolized by gut microbiota. The cholesterol metabolites have been proposed as promoters of colorectal cancer (CRC), while the effect of plant sterol metabolites is unknown. This study aimed to evaluate the cytotoxicity of metabolites from cholesterol (coprostanol, cholestanol, coprostanone and cholestenone) and β-sitosterol (ethylcoprostanol) on human colon tumor (Caco-2) and non-tumor (CCD-18Co) cells at physiological concentrations (9-300 μM) and exposure time (24 h). Ethylcoprostanol reduced the tumor cell proliferation (MTT), showing in flow cytometry assays induction of apoptosis via production of reactive oxygen species (ROS) and ceramide. Transcriptomic analysis (qPCR) showed activation of the intrinsic apoptosis pathway (BAX/BCL2 ratio and CASP9 increased), accompanied by downregulation of the p21 gene. Cholesterol metabolites, mainly the most hydrophobic, induced apoptosis and G0/G1 phase arrest in non-tumor cells through overproduction of ROS. Both the intrinsic and extrinsic (CASP8 increased) apoptosis pathways occurred. In turn, a reduction in the expression of the cyclin E1 gene confirmed the cell cycle arrest. In addition, ethylcoprostanol protected non-tumor cells from the most cytotoxic cholesterol metabolite (cholestenone). In conclusion, ethylcoprostanol is a promising candidate as a therapeutic adjuvant in CRC, while cholesterol metabolites could act as CRC promoters through their cytotoxicity.

Food biopolymer behaviors in the digestive tract: implications for nutrient delivery

Biopolymers are prevalent in both natural and processed foods, serving as thickeners, emulsifiers, and stabilizers. Although specific biopolymers are known to affect digestion, the mechanisms behind their influence on the nutrient absorption and bioavailability in processed foods are not yet fully understood. The aim of this review is to elucidate the complex interplay between biopolymers and their behavior in vivo, and to provide insights into the possible physiological consequences of their consumption. The colloidization process of biopolymer in various phases of digestion was analyzed and its impact on nutrition absorption and gastrointestinal tract was summarized. Furthermore, the review discusses the methodologies used to assess colloidization and emphasizes the need for more realistic models to overcome challenges in practical applications. By controlling macronutrient bioavailability using biopolymers, it is possible to enhance health benefits, such as improving gut health, aiding in weight management, and regulating blood sugar levels. The physiological effect of extracted biopolymers utilized in modern food structuring technology cannot be predicted solely based on their inherent functionality. It is essential to account for factors such as their initial consuming state and interactions with other food components to better understand the potential health benefits of biopolymers.

Evaluation of Different Advanced Approaches to Simulation of Dynamic In Vitro Digestion of Polyphenols from Different Food Matrices-A Systematic Review

Phenolic compounds have become interesting bioactive antioxidant compounds with implications for obesity, cancer and inflammatory gastrointestinal pathologies. As the influence of digestion and gut microbiota on antioxidant behavior is yet to be completely elucidated, and due to limitations associated to in vivo studies, dynamic in vitro gastrointestinal models have been promoted. A systematic review was conducted of different databases (PubMed, Web of Science and Scopus) following PRISMA guidelines to assess different dynamic digestion models and assay protocols used for phenolic compound research regarding bioaccesibility and interaction with colonic microbiota. Of 284 records identified, those including dynamic multicompartmental digestion models for the study of phenolic compound bioaccesibility, bioactivity and the effects of microbiota were included, with 57 studies meeting the inclusion criteria. Different conditions and experimental configurations as well as administered doses, sample treatments and microbiological assays of dynamic digestion studies on polyphenols were recorded and compared to establish their relevance for the dynamic in vitro digestion of phenolic compounds. While similarities were observed in certain experimental areas, a high variability was found in others, such as administered doses. A description of considerations on the study of the digestion of phenolic compounds is proposed to enhance comparability in research.

Polysaccharides from Cordyceps militaris prevent obesity in association with modulating gut microbiota and metabolites in high-fat diet-fed mice

Improved gut microbes and nutritious metabolites have been considered as the mediators of health benefits from indigestible polysaccharides, but their role in the anti-obesity effect of polysaccharides from Cordyceps militaris (CMP) remains elusive. This study aims to explore the potential mediators of the anti-obesity effects of CMP in high-fat diet (HFD)-fed mice using 16S rRNA sequencing and untargeted metabolomics analysis. The results showed that CMP supplementation in HFD-fed mice reduced body weight, fat accumulation, pro-inflammatory cytokine levels, and impaired glucose tolerance as well as gut barrier. Moreover, the CMP reversed the HFD-induced gut microbiota dysbiosis, as indicated by the elevated population of Alloprevotella, Parabacteroides, Butyricimonas, and Alistipes; and decreased population of Negativebacillus, in addition to altered levels of metabolites, such as brassicasterol and 4'-O-methylkanzonol W. Notably, CMP prevented obesity in association with the altered gut microbes and metabolites. These findings suggest that CMP may serve as a potential prebiotic agent to modulate specific gut microbes and related metabolites, which play a critical role in its preventing obesity-related diseases.

Elderly gastrointestinal conditions increase sterol bioaccessibility in a plant sterol-enriched beverage: adaptation of the INFOGEST method

Elderly people suffer from a higher cardiovascular risk. Thus, the fortification of foods with plant sterols (PSs), which have a cholesterol-lowering function, could be of great interest for this target group. To date, no studies have analyzed how the gastrointestinal conditions of the elderly affect PS bioaccessibility. Therefore, this study evaluated the impact of the adaptation of the gastric phase alone and in combination with the intestinal phase on sterol bioaccessibility. For this purpose, the standardized INFOGEST 2.0 method previously adapted for sterol bioaccessibility evaluation in healthy adults was applied to PS-enriched milk-based fruit beverages, examining changes in enzyme activity, incubation time, agitation and pH, based on elderly physiology. The results suggest that the specific gastrointestinal conditions of the elderly could increase absorption of PSs, since their bioaccessibility (%) in a PS-enriched milk-based fruit beverage was significantly increased compared with that in adults (14.95 ± 0.33 vs. 7.96 ± 0.26), also indicating that these conditions increase the bioaccessibility of the beverage's own cholesterol (61.25 ± 2.91 vs. 20.86 ± 2.79). These data support the recommendation of foods of this type for the elderly who can benefit from the increase in bioaccessibility of PSs to have an improved potential cholesterol lowering effect, thus decreasing their risk of cardiovascular disease. However, the performance of subsequent in vivo tests to confirm these results is necessary.

Influence of Galactooligosaccharides on the Positive Effect of Plant Sterol-Enriched Beverages on Cardiovascular Risk and Sterol Colon Metabolism

In the present study, the impact of galactooligosaccharide (GOS) addition to a plant sterol (PS)-enriched beverage on the hypocholesterolemic effect and on the bioavailability and colonic metabolization of sterols was evaluated. A crossover trial was undertaken in postmenopausal women who intook a PS-enriched (2 g PS/day) or PS-GOS-enriched beverage (2 g PS/day and 4.3 g GOS/day) for 6 weeks. The presence of GOS did not modify the hypocholesterolemic effect of the PS-enriched beverage (total- and low-density lipoprotein-cholesterol reductions) or sterol bioavailability (increments of serum markers of dietary PS intake and of cholesterol synthesis). The consumption of both beverages led to an increase of sterol and metabolite excretion (with the exception of coprostanol, which decreased) and to slight changes in women's capacities for sterol conversion, regardless of the GOS presence. This study demonstrates the suitability of simultaneous enrichment with PS and GOS in milk-based fruit beverages, considering their hypocholesterolemic effect.