Circadian rhythm plays a crucial role in maintaining intestinal homeostasis, and conversely, the remodeling of gut microbiota can help regulate circadian rhythm. Although traditional therapeutic strategies involving oral small-molecule drugs can modulate the intestinal health in circadian rhythm disruption (CRD), they are limited by restricted efficacy, dependence, and side effects. Herein, astaxanthin (AXT) and Spirulina platensis (SP) were used to prepare an innovative complex (AXT@SP) by a simple one-step synthesis method to alleviate the excessive intestinal reactive oxygen species (ROS) in CRD. The AXT@SP successfully achieved efficient loading of AXT with the drug loading efficiency of 34.56% and extended the retention time of AXT in the intestine for more than 12 h. As expected, AXT@SP reduced the intestinal ROS generation by 40.7%, restored the circadian oscillation of antioxidant-related indicators, protected the intestinal immune barrier, and reshaped the gut microbiota composition in the intestine of CRD mice. Importantly, AXT@SP restored the circadian peak of γ-aminobutyric acid during the physiological sleeping phase and regulated the phase advance of cortisol at ZT12. Our results suggested that AXT@SP could be exploited as a promising strategy for regulating CRD-related intestinal homeostasis via the gut-brain axis.

Food-borne fluorescent carbon dots (FFCDs) are a new type of endogenous fluorescent nano-particles produced in food processing. The formation of FFCDs involves in the complex physical and chemical conversion process and interaction of nutrients in food processing. FFCDs generally have particle size less than 10 nm and good water solubility with abundant active functional groups on the surface. FFCDs can emit bright fluorescence under the irradiation of excitation light. They were first discovered and extracted from bread in 2012. Recent years have witnessed an upsurge of research interest in preparing FFCDs using natural green substances as a carbon source. In this review paper, the physicochemical properties, such as morphological structure and size, element composition, functional groups, and fluorescence characteristics of FFCDs derived from different food ingredients are summarized. Furthermore, it reveals the in vivo digestion process of FFCDs using an in vitro digestion model based on the unique fluorescence properties of FFCDs, highlights the biological effects of FFCDs with respect to interaction with biological molecules and antioxidant function. Finally, it concludes with a summary of the cytotoxicity and animal toxicity of FFCDs with the aim to provide a reference for risk assessment of FFCDs in food processing and research on possible health problems associated with FFCDs in the future.

In recent years, the potential impact of food-derived carbon dots (CDs) produced during the thermal processing of foods on human health has attracted the attention of many people. In this study, CDs were extracted and purified from beef roasted at 280 ℃ for 30 min and evaluated for its interaction with digestive proteases (pepsin and trypsin) by in vitro simulated digestion, fluorescence spectroscopy, synchronous fluorescence spectroscopy, Fourier transform infrared (FTIR) spectroscopy and thermodynamic analysis. The results of simulated digestion in vitro showed that the CDs could interact with digestive proteases. Fluorescence spectroscopic analysis showed that the CDs statistically quenched the inherent fluorescence of digestive proteases. The synchronous fluorescence results demonstrated that tyrosine was involved in the interaction. The thermodynamic results showed that the binding mode of the CDs and digestive proteases was electrostatic or hydrophobic interaction, and the combination affected the secondary structure of pepsin and trypsin. After interaction with the CDs at 1.0 × 10^-5 mol/L, the activities of pepsin and trypsin decreased to (61.11 ± 7.36)% and (51.28 ± 3.62)% of their original value, respectively.

The development of rodent models that accurately reflect the pathogenesis of alcoholic liver disease (ALD) in humans is crucial for evaluating the nutritional intervention of food bioactive ingredients in ALD. Although various models have been employed to establish ALD models over the past few decades, most successful cases are associated with high mortality rates, operational difficulties, and incompatibility formation mechanism compared to human ALD. However, the ALD models established by oral administration that simulate human drinking behavior often fail to induce significant liver damage. Therefore, it is imperative to explore simple and effective modes of oral administration for establishing ALD models consistent with the pathophysiological process of human ALD. Herein, we summarized the pathogenesis of ALD and discussed several issues related to construct ALD models with rodents (mainly mice and rats) by oral administration, including animal selection, animal feeding, alcohol intervention, and evaluation criteria. The purpose of this review is to provide a standardized and efficient formula for ALD modeling, so as to facilitate efficacy evaluation and mechanism analysis of food bioactive ingredients in ALD.

This study demonstrated the design of whey protein isolate (WPI)-mannose (Man) conjugates with triphenylphosphonium bromide (TPP) through self-assembly to prepare macrophage and mitochondrion dual-targeting astaxanthin (AXT) nanoparticles (AXT@TPP-WPI-Man). The nanoparticles displayed spherical structures with a well-dispersed size of approximately 206.1 ± 39.2 nm, with good biocompatibility, stability, and targeting capabilities. In vitro experiments demonstrated the specific accumulation of AXT@TPP-WPI-Man in mitochondria and exhibited good targeting ability toward macrophages. The AXT@TPP-WPI-Man effectively reduced reactive oxygen species and preserved the normal mitochondrial membrane potential. The AXT@TPP-WPI-Man treated ulcerative colitis mice exhibited a 52.32% increase in colon length with significant improvement in weight loss, disease activity index scores, and reduced release of inflammatory cytokines. Immunofluorescence staining indicated AXT@TPP-WPI-Man alleviated ulcerative colitis by reducing M1 polarization in colonic macrophages while promoting M2 polarization. The dual-targeting AXT@TPP-WPI-Man has the potential to improve astaxanthin bioavailability, presenting a promising delivery method for the treatment of ulcerative colitis.

Oxidative stress is considered as a critical factor in the process of pathological diseases, and mitochondria are considered as vital target organelles for disease intervention. The purpose of this study was aimed to evaluate the antioxidant efficacy of mitochondria-targeted astaxanthin nanoparticle on hydrogen peroxide-induced oxidative damage. As expected, mitochondria-targeted nanoparticle showed excellent mitochondria co-localization ability with higher Pearson’s correlation coefficient (r = 0.88). In vitro experiments suggested that the mitochondria-targeted astaxanthin nanoparticle could promote cell viability and increase antioxidant-related enzyme activities. Simultaneously, metabolomics analysis indicated that mitochondria-targeted astaxanthin nanoparticle could alleviate oxidative stress by regulating amino acid metabolism and energy metabolism. Altogether, all these results strongly confirmed the mitochondria-targeted strategy for astaxanthin delivery could relieve oxidative stress and had great promise in the application of disease intervention.

The aim of this study is to investigate the feasibility of Maillard reaction products of Haematococcus pluvialis protein and galactose (HPP-GAL) for improving the bioactivities of curcumin (CUR) for alleviating alcoholic liver damage. CUR was embedded into HPP-GAL nanoparticles by the self-assembly of hydrogen bonding and hydrophobic interaction with the particle size around 200 nm. HPP-GAL enhanced the encapsulation efficiency and loading amount of CUR with the value of (89.21 ± 0.33)% and (0.500 ± 0.004)%, respectively. The stabilities of CUR under strong acid, salt ion stability and ultraviolet irradiation conditions were improved by the encapsulation. HPP-GAL-CUR nanoparticles exhibited excellent concentration-dependent in vitro antioxidant activities including DPPH and ABTS scavenging rates, and better protective effect on CUR against gastric acid environment as well as longer release of CUR in simulated intestinal fluid. In addition, the HPPGAL-CUR delivery system possessed liver targeting property due to the existence of GAL, which could effectively alleviate the alcohol-induced liver damage and the inflammation indexes by inhibiting the oxidative stress. Therefore, HPP-GAL-CUR nanoparticles might be a potential candidate system for the prevention of alcoholic liver damage in the future.

Inflammation plays an important role in the occurrence and development of many inflammatory diseases. The purpose of this study was to evaluate the anti-inflammatory effect and metabolic behavior of the dual targeting procyanidins (PC) nanoparticles on lipopolysaccharide (LPS)-stimulated inflammatory macrophages by metabolomics method. The double-targeting PC nanoparticles could specifically target both the CD44 receptor and mitochondria, while the single targeting PC-loaded nanoparticles that could target the CD44 receptor on the surface of macrophages. The double-targeting PC nanoparticles had better inhibitory effect than single-targeting PC nanoparticles on the leakage of lactate dehydrogenase and reactive oxygen species overexpression induced by LPS. Amino acid metabolism, energy metabolism and purine metabolism were disordered in LPS-treated group, and metabolic pathway analysis indicated that the double-targeting PC nanoparticles reversed some of LPS impacts. The changes of these potential biomarkers and their corresponding pathways are helpful to further understand the mechanism of PC nanoparticles in alleviating inflammation, and promote their application in nutrition intervention.

Cellular senescence is the results of aging and age-related diseases, and the development of anti-aging methods may improve health and extend longevity. The natural flavonol fisetin has been shown to antagonize senescence in vitro and increases longevity in vivo, but has poor water solubility and limited bioavailability. In this study, a food-grade and senescent cell-targeted delivery system for fisetin was developed based on whey protein isolate-galactooligosaccharides (WPI-GOS) Maillard conjugate, which could recognize senescence associated β-galactosidase in senescent cells. The fisetin nanoparticles possessed a high encapsulation efficiency, excellent dispersibility in water, good storage stability and well biocompatibility. Moreover, they could effectively accumulate and retain in senescent cells with excellent senescent cell-targeting efficacy, and inhibit the oxidative stress-induced cellular senescence in vitro. Thus, this novel nanoparticle system based on WPI-GOS Maillard conjugate showed promise to deliver hydrophobic bioactive ingredients like fisetin to senescent cells to improve their bioavailability and anti-senescence effect.