Construction and characterization of Juglans regia L. polyphenols nanoparticles based on bovine serum albumin and Hohenbuehelia serotina polysaccharides, and their gastrointestinal digestion and colonic fermentation in vitro

A glutenin protein corona ameliorated TiO2 nanoparticle-induced gut barrier dysfunction and altered the gut microbiota composition

Previously, we found that glutenin proteins formed a protein corona around food-grade titanium dioxide (TiO2) nanoparticles. The protein corona would alter the gastrointestinal behavior and biological activity of the nanoparticles. Here, in this study, the influence of protein corona formation on the adverse effects of TiO2 nanoparticles on gut barrier function using in vitro and in vivo assays and the potential mechanism were investigated and elucidated. Our findings showed that the presence of the protein corona mitigated gut barrier injury caused by TiO2 nanoparticles while increasing gene expression for tight junction proteins; for example, in vitro gastrointestinal digestion and fermentation experiments showed that the glutenin-TiO2 protein corona was relatively stable to digestion and influenced the composition of the gut microbiota. Specifically, the glutenin-TiO2 protein corona increased the relative abundance of beneficial bacteria such as Bifidobacterium, Parasutterella, and Bacillus while reducing the relative abundance of harmful bacteria like Streptococcus. Moreover, the formation of the protein corona reduced the cytotoxicity of the TiO2 nanoparticles to Caco-2 and RAW264.7 cells. Mechanistically, we found that the presence of the glutenin-TiO2 protein corona decreased the production of reactive oxygen species and increased the mitochondrial membrane potential in both Caco-2 and RAW264.7 cells compared to TiO2 nanoparticles alone. This study provides valuable mechanistic insights into the potential biological effects of protein corona formation around food inorganic nanoparticles in the food industry.

Metagenomic analysis reveals high diversity of gut viromes in yaks (Bos grunniens) from the Qinghai-Tibet Plateau

The Qinghai-Tibet Plateau (QTP), renowned for its exceptional biological diversity, is home to numerous endemic species. However, research on the virology of vulnerable vertebrates like yaks remains limited. In this study, our objective was to use metagenomics to provide a comprehensive understanding of the diversity and evolution of the gut virome in yak populations across different regions of the QTP. Our findings revealed a remarkably diverse array of viruses in the gut of yaks, including those associated with vertebrates and bacteriophages. Notably, some vertebrate-associated viruses, such as astrovirus and picornavirus, showed significant sequence identity across diverse yak populations. Additionally, we observed differences in the functional profiles of genes carried by the yak gut virome across different regions. Moreover, the virus-bacterium symbiotic network that we discovered holds potential significance in maintaining the health of yaks. Overall, this research expands our understanding of the viral communities in the gut of yaks and highlights the importance of further investigating the interactions between viruses and their hosts. These data will be beneficial for revealing the crucial role that viruses play in the yak gut ecology in future studies.

Recent Progress of Oral Functional Nanomaterials for Intestinal Microbiota Regulation

The gut microbiota is closely associated with human health, and alterations in gut microbiota can influence various physiological and pathological activities in the human body. Therefore, microbiota regulation has become an important strategy in current disease treatment, albeit facing numerous challenges. Nanomaterials, owing to their excellent protective properties, drug release capabilities, targeting abilities, and good biocompatibility, have been widely developed and utilized in pharmaceuticals and dietary fields. In recent years, significant progress has been made in research on utilizing nanomaterials to assist in regulating gut microbiota for disease intervention. This review explores the latest advancements in the application of nanomaterials for microbiota regulation and offers insights into the future development of nanomaterials in modulating gut microbiota.

Biyang floral mushroom-derived exosome-like nanovesicles: characterization, absorption stability and ionizing radiation protection

Diet-derived exosome-like nanovesicles are a class of natural active substances that have similar structures and functions to mammalian exosomes. Biyang floral mushrooms and their active extracts have been found to possess radioprotective effects and to deeply explore their novel active substances, the radioprotective effects of Biyang floral mushroom-derived exosome-like nanovesicles (BFMELNs) were investigated in this study. Results showed that these surface-negatively charged vesicles possessed an ideal size and good stability against environmental changes such as temperature and gastrointestinal digestion. Furthermore, BFMELNs could effectively be taken up by HL-7702 cells and Caco-2 cells through cellular phagocytosis mediated by clathrin and dynein. Emphatically, BFMELNs with an exosome-like morphology contained RNA, proteins, lipids, polyphenols and flavonoids to exert good antioxidant and radioprotective effects in vitro. Meanwhile, BFMELNs also exhibited good radioprotective effects by restoring peripheral blood indexes, mitigating damage to organs, and regulating the redox state in mice. Collectively, BFMELNs showed promise as novel and natural radioprotective nano-agents for preventing IR-induced oxidative stress damage.

Impact of Whey Protein Corona Formation around TiO2 Nanoparticles on Their Physiochemical Properties and Gastrointestinal Fate

Previously, we found that whey proteins form biomolecular coronas around titanium dioxide (TiO2) nanoparticles. Here, the gastrointestinal fate of whey protein-coated TiO2 nanoparticles and their interactions with gut microbiota were investigated. The antioxidant activity of protein-coated nanoparticles was enhanced after simulated digestion. The structure of the whey proteins was changed after they adsorbed to the surfaces of the TiO2 nanoparticles, which reduced their hydrolysis under simulated gastrointestinal conditions. The presence of protein coronas also regulated the impact of the TiO2 nanoparticles on colonic fermentation, including promoting the production of short-chain fatty acids. Bare TiO2 nanoparticles significantly increased the proportion of harmful bacteria and decreased the proportion of beneficial bacteria, but the presence of protein coronas alleviated this effect. In particular, the proportion of beneficial bacteria, such as Bacteroides and Bifidobacterium, was enhanced for the coated nanoparticles. Our results suggest that the formation of a whey protein corona around TiO2 nanoparticles may have beneficial effects on their behavior within the colon. This study provides valuable new insights into the potential impact of protein coronas on the gastrointestinal fate of inorganic nanoparticles.

Multifunctional nanogel based on carboxymethyl cellulose interfering with cellular redox homeostasis enhances phycocyanobilin photodynamic therapy

The redox homeostasis defense mechanism of tumor cells is one of the prime reasons for the unsatisfactory effect of photodynamic therapy (PDT). So far, little attention has been paid to this obstacle. In this work, we reported a synthesizing simple yet versatile nanogel (BCPS), synthesized by cystamine dihydrochloride functionalized sodium carboxymethylcellulose (CMC-SS), bovine serum albumin, and Phycocyanobilin self-assembly. The BCPS reduced the levels of glutathione molecules by reacting with glutathione, thereby interfering with intracellular redox homeostasis and enhancing the sensitivity of tumor cells to PDT. The BCPS was shown to possess excellent serum stability, high blood compatibility, low toxic side effects, and higher reactive oxygen species (ROS) utilization. After irradiation, the BCPS could significantly increase intracellular ROS level by approximately 1.6-fold and decrease the IC50 to HeLa cells by approximately 1.5-fold, compared to the pre-functional drugs BCP. This proposed strategy, based on increasing the utilization rate of ROS in tumor cells is promising for application potentials in tumor therapy.

Polysaccharides from the hard shells of Juglans regia L. modulate intestinal function and gut microbiota in vivo

This study aimed to investigate the modulatory effects of polysaccharides from the hard shells ofJuglans regiaL. (JRP) on intestinal function and gut microbiota of mice. The results showed that JRP could increase the colonic length and colonic index, and ameliorate the histological characteristics of colon. JRP had a positive effect on immunity of mice by improving immune organ indexes. Owing to enhancement of intestinal peristalsis and increase of colonic fecal moisture by JRP, the defecation time was significantly reduced. After gastrointestinal digestion and absorption, JRP was metabolized by intestinal microorganisms to produce short chain fatty acids, thereby lowering the pH of intestine. Through microbial community analysis, the composition of gut microbiota was modulated by JRPvia increasing theabundances of beneficial bacteriaand decreasing the richness of harmful bacteria. This study suggests that JRP can be served as an excellent prebiotic to promote intestinal health.

Nanoparticles prepared by polysaccharides extracted from Biyang floral mushroom loaded with resveratrol: Characterization, bioactivity and release behavior under in vitro digestion

Resveratrol (RES) is a common active factor in the functional food field, but poor water solubility and low bioavailability have limited its application. In the present study, the novel nanoparticles (RES-CBFMP NPs) using floral mushroom polysaccharide as the wall material have been developed for delivering RES, aiming to overcome its application shortcomings. After ratio optimization, RES-CBFMP NPs (RES-CBFMP,1:8 w/w), which combined through the hydrogen bonds between RES and CBFMP, showed the best overall performance, with the encapsulation efficiency (EE) of 49.74 ± 0.16%, loading efficiency (LE) of 5.53 ± 0.02%, particle size of 158.56 ± 1.97 nm and zeta-potential of -17.56 ± 0.24 mV. In addition, RES-CBFMP NPs exhibited good physicochemical stabilities, sustained gastrointestinal digestive release property, as well as improved in vitro antioxidant and anticancer activities. This study may contribute to the development of RES oral delivery systems and the application of hydrophobic active molecules in the functional food field.

Properties of selenium nanoparticles stabilized by Lycium barbarum polysaccharide-protein conjugates obtained with subcritical water

Selenium nanoparticles (SeNPs) in an aqueous solution have poor stability and tend to aggregate when stored for a long time. In the present study, SeNPs were stabilized by using Lycium barbarum polysaccharide (LBP) and Lycium barbarum protein (LBPr) conjugates (LBPP) as a stabilizer and dispersing agent. Particularly, the LBPP₁ was obtained with subcritical water treatment. In addition, the physical stability, re-dispersity and antitumor activity of LBPP₁-SeNPs were investigated. The results showed the particle size of LBPP₁-SeNPs was maintained at 111.5-117 nm, which was stable at PH 6, 4 °C and darkness for at least 40 days. Besides, the result of TEM showed that the dispersion of LBPP₁-SeNPs had more clear layers and smoother surfaces. Moreover, LBPP₁-SeNPs had excellent re-dispersibility and exhibited a significant inhibitory effect on HepG-2 cells and Caco-2 cells, respectively (p < 0.05). Therefore, LBPP₁-SeNPs can be used as potential selenium nutritional supplements for food and medical applications.

Recent development in fabrication and evaluation of phenolic-dietary fiber composites for potential treatment of colonic diseases

Phenolics have been shown by in vitro and animal studies to have multiple pharmacological effects against various colonic diseases. However, their efficacy against colonic diseases, such as inflammatory bowel diseases, Crohn's disease, and colorectal cancer, is significantly compromised due to their chemical instability and susceptibility to modification along the gastrointestinal tract (GIT) before reaching the colonic site. Dietary fibers are promising candidates that can form phenolic-dietary fiber composites (PDC) to carry phenolics to the colon, as they are natural polysaccharides that are non-digestible in the upper intestinal tract but can be partially or fully degradable by gut microbiota in the colon, triggering the release at this targeted site. In addition, soluble and fermentable dietary fibers confer additional health benefits as prebiotics when used in the PDC fabrication, and the possibility of synergistic relationship between phenolics and fibers in alleviating the disease conditions. The functionalities of PDC need to be characterized in terms of their particle characteristics, molecular interactions, release profiles in simulated digestion and colonic fermentation to fully understand the metabolic fate and health benefits. This review examines recent advancements regarding the approaches for fabrication, characterization, and evaluation of PDC in in vitro conditions.