Viscoelastic Emulsion Improved the Bioaccessibility and Oral Bioavailability of Crystalline Compound: A Mechanistic Study Using in Vitro and in Vivo Models

The Neuroprotective Role of Tangeritin

The prevalence of neurodegenerative diseases has increased with longer life expectancies, necessitating the exploration of novel neuroprotective agents. Tangeretin, a polymethoxylated flavone derived from citrus fruits, has gathered attention for its potential therapeutic effects. This review highlights the neuroprotective properties of tangeretin via its antioxidant and anti-inflammatory mechanisms. Tangeretin demonstrates efficacy in mitigating oxidative stress, neuroinflammation, and neuronal damage across various neurodegenerative conditions, including Alzheimer's disease, Parkinson's disease, cerebral ischemia, and epilepsy. It shows promise in ameliorating cognitive deficits and memory impairments associated with these diseases. Moreover, tangeretin modulates multiple signalling pathways and protects against neuronal apoptosis, underscoring its potential as a therapeutic agent.

Progress of Researches on Pharmacological Effects and Bioavailability of Tangeretin

Tangeretin is one of the most abundant polymethoxyflavones in citrus peel and its pharmacological effects are extremely rich. However, due to its poor solubility, bitter taste and poor oral bioavailability, the oral administration of tangeretin is still limited, which seriously limits its application in industrial production. The establishment of encapsulation and delivery systems to improve bioavailability is an effective method. This paper reviewed the research progress of the structure and properties, pharmacological effects and main methods to improve bioavailability of tangeretin, including emulsion delivery, lipid encapsulation, microencapsulation and other delivery and utilization research and application. The article aims to provide theoretical basis for the high-value application of tangeretin in functional food and pharmaceutical industry.

Citrus Polymethoxyflavones Regulate against Aging-Associated Diseases: Advances in Biological Mechanisms Responsible for Their Regulation

As the proportion of the aging population globally is surging year by year, age-associated diseases, including neurodegenerative, metabolic, and cardiovascular diseases, have recently attracted widespread attention of food scientists and nutritionists. Polymethoxyflavonoids (PMFs), a type of dietary flavonoids, have emerged as potential antiaging candidates owing to their diverse bioactivities, encompassing antioxidant, anti-inflammatory, neuroprotective, and metabolic regulatory effects. Herein, this comprehensive updated review has summarized and discussed the effects of PMFs on aging, and the possible mechanisms that link PMFs-mediated modulation and the prevention or treatment of various aging-related diseases have been elaborated in detail. Furthermore, the biological fate of PMFs have been discussed elaborately from their absorption, distribution, metabolism, and excretion in vivo. Special attention is given to the bioavailability-bioactivity relationship of PMFs, as PMF's biological activity is significantly hampered by poor bioavailability. Overall, all of these conclusions may help in providing a perspective for further study of PMFs on aging.

Natural product nobiletin-loaded Pickering emulsion stabilized by bovine serum albumin/carboxymethyl inulin complexes: preparation and digestive characteristics

To expand the application of nobiletin (NOB) in semi-solid functional foods, bovine serum albumin (BSA)/carboxymethyl inulin (CMI) complexes-stabilized Pickering emulsion (BCPE) (φoil = 60%, v/v) was fabricated, and the swallowing index and bioavailability of the NOB-loaded Pickering emulsion was evaluated. Confocal laser scanning microscope (CLSM) and cryo-scanning electron microscopy (cryo-SEM) images revealed that BSA/CMI complexes attached to the oil-water interface. NOB-loaded BCPE exhibited a viscoelastic and shear-thinning behavior. Fork drip test results suggested that the textural value of unloaded and NOB-loaded emulsions was International Dysphagia Diet Standardisation Initiative Level 4, which could be swallowed directly without chewing. The in vitro lipolysis model suggested that NOB had a faster digestive profile and a higher bioaccessibility in the BCPE than in the oil suspension. The in vivo rat model revealed that the oral bioavailability of NOB was increased by 2.07 folds in BCPE compared to its bioavailability in unformulated oil. Moreover, BCPE led to a higher plasma concentration of the major demethylated metabolite of NOB (4'-demethylnobiletin) than the unformulated oil. Accordingly, BCPE enhanced the oral bioavailability of NOB by improving bioaccessibility, absorption, and biotransformation.

Polymethoxylated flavonoids in citrus fruits: absorption, metabolism, and anticancer mechanisms against breast cancer

Polymethoxylated flavonoids (PMFs) are a subclass of flavonoids found in citrus fruits that have shown multifunctional biological activities and potential anticancer effects against breast cancer. We studied the absorption, metabolism, species source, toxicity, anti-cancer mechanisms, and molecular targets of PMFs to better utilize their anticancer activity against breast cancer. We discuss the absorption and metabolism of PMFs in the body, including the methylation, demethylation, and hydroxylation processes. The anticancer mechanisms of PMFs against breast cancer were also reviewed, including the estrogen activity, cytochrome P-450 enzyme system, and arylhydrocarbon receptor (AhR) inhibition, along with various molecular targets and potential anticancer effects. Although PMFs may be advantageous in the prevention and treatment for breast cancer, there is a lack of clinical evidence and data to support their efficacy. Despite their promise, there is still a long way to go before PMFs can be applied clinically.

Effect of Food and a Proton-Pump Inhibitor on the Absorption of Encorafenib: An In Vivo-In Vitro-In Silico Approach

Encorafenib is a kinase inhibitor indicated for the treatment of patients with BRAF mutant melanoma and BRAF mutant metastatic colorectal cancer. To understand the effect of food and coadministration with a proton-pump inhibitor (PPI), in vitro, in vivo, and in silico data were generated to optimize the clinical dose, evaluate safety, and better understand the oral absorption process under these conditions. Study 1 evaluated the effect of food on the plasma pharmacokinetics, safety, and tolerability after a single oral dose of encorafenib 100 mg. Study 2 evaluated the same end points with coadministration of encorafenib and rabeprazole (PPI perpetrator). The in vitro gastrointestinal TIM-1 model was used to investigate the release of encorafenib and the amount available for absorption under different testing conditions (fasted, fed, and with the use of a PPI). The fasted, fed, and PPI states were predicted for the encorafenib commercial capsule in GastroPlus 9.8. In study 1, both AUC_inf and AUC_last decreased by 4% with the administration of a high-fat meal. The C_max was 36% lower than with fasted conditions. All 3 exposure parameters in study 2 (AUC_inf, AUC_last, and C_max) had mean changes of <10% when encorafenib was coadministered with a PPI. Using the in vitro gastrointestinal simulator TIM-1, the model demonstrated a similar release of drug, as the bioaccessible fraction, in the 3 conditions was equal (≥80%), predicting no PPI or food effect for this drug formulation. The modeling in GastroPlus 9.8 demonstrated complete absorption of encorafenib when formulated as an amorphous solid dispersion. To obtain these results, it was crucial to integrate the amorphous solubility of the drug that shows a 20-fold higher solubility at pH 6.8 compared with crystalline solubility. The increased amorphous solubility is likely the reason no PPI effect was observed compared with fasted state conditions. The prolongation in gastric emptying in the fed state resulted in delayed plasma T_max for encorafenib. No dose adjustment is necessary when encorafenib is administered in the fed state or when coadministered with a PPI. Both the TIM-1 and physiologically based pharmacokinetic model results were consistent with the observed clinical data, suggesting that these will be valuable tools for future work.

Recent developments in citrus bioflavonoid encapsulation to reinforce controlled antioxidant delivery and generate therapeutic uses: Review

Citrus fruits contain numerous antioxidative biomolecules including phenolic acids, flavonols, flavanones, polymethoxyflavones (PMFs), and their derivatives. Previous in vitro and in vivo studies thoroughly investigated the antioxidant and therapeutic potential of bioflavonoids extracted from different citrus varieties and fruit fractions. Major bioflavonoids such as hesperidin, naringin, naringenin, and PMFs, had restricted their incorporation into food and health products due to their poor solubility, chemical stability and bioavailability. Considering these limitations, modern encapsulation methodologies such as hydrogelation, liposomal interactions, emulsifications, and nanoparticles have been designed to shield bioflavonoids with improved target distribution for therapeutic enhancements. The size, durability, and binding efficiency of bioflavonoid-loaded encapsulates were acquired by the optimized chemical and instrumental parameters such as solubility, gelation, dispersion, extrusion, and drying. Bioflavonoid-enriched encapsulates have been also proven to be effective against cancer, inflammation, neurodegeneration, and various other illnesses. However, in the future, newer natural binding agents with higher binding capacity might accelerate the encapsulating potential, controlled release, and enhanced bioavailability of citrus bioflavonoids. Overall, these modern encapsulation systems are currently leading to a new era of diet-based medicine, as demand for citrus fruit-based nutritional supplements and edibles grows.

Effect of Fibril Entanglement on Pickering Emulsions Stabilized by Whey Protein Fibrils for Nobiletin Delivery

The aim of the study was to investigate the effects of whey protein isolate (WPI) fibrils entanglement on the stability and loading capacity of WPI fibrils-stabilized Pickering emulsion. The results of rheology and small-angle X-ray scattering (SAXS) showed the overlap concentration (C*) of WPI fibrils was around 0.5 wt.%. When the concentration was higher than C*, the fibrils became compact and entangled in solution due to a small cross-sectional radius of gyration value (1.18 nm). The interfacial behavior was evaluated by interfacial adsorption and confocal laser scanning microscopy (CLSM). As the fibril concentration increased from 0.1 wt.% to 1.25 wt.%, faster adsorption kinetics (from 0.13 to 0.21) and lower interfacial tension (from 11.85 mN/m to 10.34 mN/m) were achieved. CLSM results showed that WPI fibrils can effectively absorb on the surface of oil droplets. Finally, the microstructure and in vitro lipolysis were used to evaluate the effect of fibrils entanglement on the stability of emulsion and bioaccessibility of nobiletin. At C* concentration, WPI fibrils-stabilized Pickering emulsions exhibited excellent long-term stability and were also stable at various pHs (2.0–7.0) and ionic strengths (0–200 mM). WPI fibrils-stabilized Pickering emulsions after loading nobiletin remained stable, and in vitro digestion showed that these Pickering emulsions could significantly improve the extent of lipolysis (from 36% to 49%) and nobiletin bioaccessibility (21.9% to 62.5%). This study could provide new insight into the fabrication of food-grade Pickering emulsion with good nutraceutical protection.

Nutraceutical potential of industrial hemp (Cannabis sativa L.) extracts: physicochemical stability and bioaccessibility of cannabidiol (CBD) nanoemulsions

Cannabidiol (CBD) is one of the most promising functional food ingredients, which displays a number of health benefits. However, its low solubility and bioavailability impede its applications in functional foods. Herein, we developed a food-grade CBD nanoemulsion system using medium chain triacylglycerides (MCT), canola oil (CO), or hemp seed oil (HSO) as the carrier oil to compare the physicochemical stability and bioaccessibility of CBD. Encouragingly, all formulations were well maintained for 90 days under the tested temperatures (4, 25 and 37 °C) and pH values (3.5 and 7.0). Quantitative analysis of CBD during storage using high performance liquid chromatography revealed that the light exposure and acidity of the solution are two important factors affecting the chemical stability of CBD. Moreover, improved bioaccessibility of CBD in all three nanoemulsion formulations compared to that of bulk oil forms was confirmed, and the long chain triacylglyceride (LCT)-based nanoemulsion was superior to the MCT-based counterpart.

Fabrication and in vitro digestion behavior of Pickering emulsions stabilized by chitosan-caseinophosphopeptides nanocomplexes

The nanocomplexes assembled from chitosan (CS) and caseinophosphopeptides (CPPs) were utilized to stabilize Pickering emulsions with medium-chain triglyceride (MCT) as the oil phase. The CS-CPPs nanocomplexes composed of CS:CPPs = 1:1, 2:1, 4:1 were prepared and their physical properties including particle size, contact angle, and surface tension were characterized. The concentration ranges of these nanocomplexes that can stabilize Picking emulsion decreased in the following sequence, CS:CPPs = 1:1 (C1P1) > 2:1 (C2P1) > 4:1 (C4P1). The fraction of oil that can be stabilized by these three kinds of nanocomplexes at 0.15 wt% concentration was similar, and increasing the concentration of nanocomplexes can stabilize a higher fraction of MCT. The fluorescence microscopy image indicated that the Pickering emulsions were oil-in-water type emulsions. These emulsions were stable against ionic strength (0-0.3 M NaCl) changes after 24 h storage but low pH (pH 2) could affect their stabilities. These CS-CPPs nanocomplexes stabilized Pickering emulsions showed gel-like behavior. In vitro lipolysis studies revealed that coverage of the CS-CPPs nanocomplexes at the oil-water interface could reduce the rate and extent of MCT digestion, manifesting that they may potentially be used as fat replacers in foods to reduce oil absorption.

In-vitro digestion models: a critical review for human and fish and a protocol for in-vitro digestion in fish

Digestive systems in human, animals, and fish are biological reactors and membranes to digest food and extract nutrients. Therefore, static and dynamic models of in-vitro digestion systems are developed to study e.g. novel food and feed before in-vivo studies. Such models are well developed for human, but not to the same extent for animals and fish. On the other hand, recent advances in aquaculture nutrition have created several potential fish meal replacements, and the assessment of their nutrient digestibility is critical in the application as a fish meal replacement. Using an in-vitro method, the assessment of an ingredient digestibility could be faster and less expensive compared to using an in-vivo experiment. An in-vitro method has been widely used to assess food nutrient digestibility for humans; however, its application for fish is still in the early stages. Both the human and fish as monogastric vertebrates share similar gastrointestinal systems; thus, the concept from the application for humans could be applied for fish. This review aims to improve the in-vitro digestion protocol for fish by adapting the concept from then study for humans, summarizing the current available in-vitro digestion model developed for human and fish in-vitro digestion study, identifying challenges specifically for fish required to be tackled and suggesting an engineering approach to adapt the human in-vitro gastrointestinal model to fish. Protocols to conduct in-vitro digestion study for fish are then proposed.

Development of organogel-based emulsions to enhance the loading and bioaccessibility of 5-demethylnobiletin

5-Demethylnobiletin (5-DMN), identified in the aged citrus peels, has received increasing attentions due to its outstanding bioactivity among citrus polymethoxyflavones (PMFs). However, the poor water solubility and high crystallinity limit its oral bioavailability. Besides, the solubility of 5-DMN in the oil is very limited, which restricts its loading capacity in emulsions for bioavailability enhancement. In this study, an organogel formulation was developed to improve the solubility of 5-DMN in medium-chain triacylglycerols by 3.5 times higher without crystal formation during 5-day storage at room temperature. Increasing the gelator (i.e., sugar ester) concentration led to the increase of viscosity and a gel-like structure of the organogel. The ternary phase diagram of organogel-based emulsions was explored, and 40% organogel was selected as the oil phase for emulsion preparation. Increasing the concentration of Tween 80 from 0% to 6% decreased the droplet size and viscoelasticity of the emulsions. Two in vitro models, the pH-stat lipolysis model and TNO gastro-intestinal model (TIM-1), were applied to investigate the bioaccessibility of 5-DMN in different delivery systems. Compared with the conventional emulsion and oil suspension, the pH-stat lipolysis demonstrated that the organogel-based emulsion was the most efficient tool to enhance 5-DMN bioacccessibility. Moreover, TIM-1 digestive study indicated that 5-DMN bioaccessibility delivered by organogel-based emulsions was about 3.26-fold higher than that of oil suspension. Our results suggested that the organogel-based emulsion was an effective delivery route to enhance the loading and bioaccessibility of lipophilic compounds of high crystallinity.

Improving oral bioavailability of medicinal herbal compounds through lipid-based formulations - A Scoping Review

BACKGROUND

Although numerous medicinal herbal compounds demonstrate promising therapeutic potential, their clinical application is often limited by their poor oral bioavailability. To circumvent this barrier, various lipid-based herbal formulations have been developed and trialled with promising experimental results.

PURPOSE

This scoping review aims to describe the effect of lipid-based formulations on the oral bioavailability of herbal compounds.

METHODS

A systematic search was conducted across three electronic databases (Medline, Embase and Cochrane Library) between January 2010 and January 2021 to identify relevant studies. The articles were rigorously screened for eligibility. Data from eligible studies were then extracted and collated for synthesis and descriptive analysis using Covidence.

RESULTS

A total of 109 studies were included in the present review: 105 animal studies and four clinical trials. Among the formulations investigated, 50% were emulsions, 34% lipid particulate systems, 12% vesicular systems, and 4% were other types of lipid-based formulations. Within the emulsion system classification, self-emulsifying drug delivery systems were observed to produce the best improvements in oral bioavailability, followed by mixed micellar formulations. The introduction of composite lipid-based formulations and the use of uncommon surfactants such as sodium oleate in emulsion preparation was shown to consistently enhance the bioavailability of herbal compounds with poor oral absorption. Interestingly, the lipid-based formulations of magnesium lithospermate B and Pulsatilla chinensis produced an absolute bioavailability greater than 100% indicating the possibility of prolonged systemic circulation. With respect to chemical conjugation, D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) was the most frequently used and significantly improved the bioavailability of its phytoconstituents.

CONCLUSION

Our findings suggest that there is no distinct lipid-based formulation superior to the other. Bioavailability improvements were largely dependent on the nature of the phytoconstituents. This scoping review, however, provided a detailed summary of the most up-to-date evidence on phytoconstituents formulated into lipid preparations and their oral bioavailability. We conclude that a systematic review and meta-analysis between bioavailability improvements of individual phytoconstituents (such as kaempferol, morin and myricetin) in various lipid-based formulations will provide a more detailed association. Such a review will be highly beneficial for both researchers and herbal manufacturers.

Improving in vitro bioaccessibility and bioactivity of carnosic acid using a lecithin-based nanoemulsion system

As a phenolic terpenoid, carnosic acid (CA) mainly exists in rosemary, which can be effectively used for the treatment of degenerative and chronic diseases by taking advantage of its health-promoting bioactivities. However, the low solubility and dissolution of CA in aqueous solutions at ambient and body temperatures result in low stability and bioaccessibility during the digestion process, which limits its application scope in the functional foods industry. In this regard, a lecithin based nanoemulsion system (CA-NE) is employed in the present work to enhance the bioaccessibility and bioactivities of CA. It is revealed that the CA-NE under investigation exhibits high loading capacity (2.80 ± 0.15%), small particle size (172.0 ± 3.5 nm) with homogeneous particle distribution (polydispersity index (PDI) of 0.231± 0.025) and high repulsive force (zeta potential = -57.2 ± 0.24 mV). More importantly, the bioaccessibility of CA-NE is improved by 2.8-fold compared to that of CA in MCT oil. In addition, the cellular antioxidant assay (CAA) and cellular uptake study of the CA-NE in HepG2 cell models demonstrate a longer endocytosis process, suggesting the well-controlled release of CA from CA-NE. Furthermore, an improved anti-inflammatory activity was evaluated via the inhibition of the pro-inflammatory cytokines, nitric oxide (NO) and TNF-α production in LPS-stimulated RAW 264.7 macrophage cells. The results clearly demonstrated a promising application of CA-NE as a functional food.

The biological fate and bioefficacy of citrus flavonoids: bioavailability, biotransformation, and delivery systems

Citrus fruits are among the most popularly consumed fruits worldwide, including oranges, grapefruits, pomelos and lemons. Citrus flavonoids such as hesperidin, naringin and nobiletin have shown an array of health benefits in cell, animal and clinical studies, including antioxidative, anti-inflammatory, neuroprotective, anticancer, and anti-obesity activities. Citrus flavonoids have limited bioavailability after oral administration, leaving the major part unabsorbed and persisted in the colon. Recent studies have highlighted the important role of the gut microbiota and in vivo biotransformation on the bioactivity of citrus flavonoids. This article discusses the biological fate of citrus flavonoids from the viewpoint of their absorption, distribution, metabolism and excretion in vivo. Many delivery systems have been designed to enhance the oral bioavailability of citrus flavonoids, such as emulsions, self-emulsifying systems, nanoparticles and solid dispersions. The ultimate goal of these delivery systems is to enhance the bioefficacy of citrus flavonoids. Several studies have found that the increased bioavailability leads to enhanced bioefficacy of citrus flavonoids in specific animal models. Regarding the complex dynamics of citrus flavonoids and gut microbiota, the bioavailability-bioactivity relationship is an interesting but under-discussed area. Comprehensively understanding the biological fate and bioefficacy of citrus flavonoids would be helpful to develop functional foods with better health benefits.

Biopolymer Additives Enhance Tangeretin Bioavailability in Emulsion-Based Delivery Systems: An In Vitro and In Vivo Study

The oral bioavailability of tangeretin, a poly(methoxyflavone) found in citrus fruits, is typically very low because of its extremely limited solubility. In this research, tangeretin was encapsulated within whey protein-stabilized emulsions containing ingredients that may alter their behavior under gastrointestinal conditions and enhance the bioavailability of tangeretin after oral administration: cinnamaldehyde (CA), gum arabic (GA), or hydroxypropyl methylcellulose (HPMC). The presence of these ingredients altered the size, aggregation state, and encapsulation efficiency of tangeretin in the emulsions. In vitro studies demonstrated that the bioaccessibility of the encapsulated tangeretin was much higher than that of a crude tangeretin oil suspension. Particularly, the addition of HPMC increased the bioaccessibility of tangeretin from around 36 to 90%. In vivo pharmacokinetics results using rats indicated that tangeretin concentration in the plasma increased from 4- to 20-fold after encapsulation, especially in the presence of HPMC. HPMC also prolonged the release of tangeretin to 22 h. Tangeretin preferentially accumulated within the liver and kidney of the animals. Overall, the knowledge confirmed that structured emulsion-based delivery systems could be used to improve the oral bioavailability of hydrophobic functional ingredients.

Effects of Lipid-Based Encapsulation on the Bioaccessibility and Bioavailability of Phenolic Compounds

Phenolic compounds (quercetin, rutin, cyanidin, tangeretin, hesperetin, curcumin, resveratrol, etc.) are known to have health-promoting effects and they are accepted as one of the main proposed nutraceutical group. However, their application is limited owing to the problems related with their stability and water solubility as well as their low bioaccessibility and bioavailability. These limitations can be overcome by encapsulating phenolic compounds by physical, physicochemical and chemical encapsulation techniques. This review focuses on the effects of encapsulation, especially lipid-based techniques (emulsion/nanoemulsion, solid lipid nanoparticles, liposomes/nanoliposomes, etc.), on the digestibility characteristics of phenolic compounds in terms of bioaccessibility and bioavailability.

Synergistic enhancement of loading contents and chemical stability of lycopene distributing both inside and on the oil/water interface

Loading contents and chemical stability of lycopene were synergistically enhanced after dispersion in genipin-crosslinked-chitosan (CS) stabilized high internal phase emulsions (HIPEs). HIPEs could be prepared with the parameters for the emulsifiers of CS concentration from 0.5 to 5 mg/mL, pH value from 5.5 to 7.5, and CS/genipin mass ratio from 2:1 to 20:1. High loading content of lycopene, up to 0.25 wt% was achieved, with emulsifier in the final system only 1 mg/mL. As the loading contents were elevated, increasing amount of lycopene distributed in HIPEs in the form of insoluble crystals. Meanwhile, density of oil droplets decreased and the shape changed from polygon to sphere, which is supposed to be related to the interaction between the crystal and the oil-water interface. Stability of lycopene against ultraviolet, temperature, hydrogen peroxide, and iron ions was improved significantly, which could be ascribed to the layer of genipin-crosslinked-CS on oil droplet surface and the crystal status of lycopene. The storage stability of lycopene was improved tremendously after encapsulation by HIPEs. PRACTICAL APPLICATION: Low loading content of lycopene in emulsion systems is not conducive to the evaluation of its biological function in subsequent experiments, as well as their real application in food industry. It is also crucial to improve the stability of lycopene for the practical application in food industry. In this work, the loading content in delivery system and the chemical stability of lycopene are improved through encapsulation with high internal phase emulsions (HIPEs). The significance of these results may have implications in fields spanning from colloidal science to functional foods applications.

Formulation and Evaluation of a Novel Itraconazole-Clotrimazole Topical Emulgel for the Treatment of Sporotrichosis

In recent years, the development of new pharmaceutical formulations for the treatment of sporotrichosis has become a relevant research field. In this work, we aimed to develop an emulgel containing itraconazole and clotrimazole to ensure therapeutic effectiveness against Sporothrix brasiliensis. The topical use of a formulation that combines both drugs represents an interesting option for the complementary treatment of sporotrichosis. The emulgel formulation was prepared and evaluated for its zeta potential, viscosity, in vitro antifungal activity and stability at different storage conditions. The results showed that the newly developed emulgel displayed promising physicochemical characteristics, as well as a good in vitro inhibitory activity against S. brasiliensis yeasts. The results obtained in this work suggest that the emulgel containing itraconazole and clotrimazole might highly be efficient and a complementary therapy to oral administration in the treatment of sporotrichosis.

Evaluation of Oral Bioaccessibility of Aged Citrus Peel Extracts Encapsulated in Different Lipid-Based Systems: A Comparison Study Using Different in Vitro Digestion Models

The oral delivery efficiency of aged citrus peel extract containing polymethoxyflavones and 5-demethylated polymethoxyflavones (PMFs) in three different systems, including a pure oil phase, a Tween 80-stabilized nanoemulsion, and a milled-cellulose-particles-stabilized Pickering emulsion, was investigated using two typical in vitro digestion models. The digestion profiles and release of PMFs in these emulsions and bulk oil in the human upper gastrointestinal (GI) tract were evaluated using the pH-stat lipolysis model and TNO's gastrointestinal model (TIM-1). Compared to the bulk oil sample, the bioaccessibilities of PMFs in the nanoemulsion and Pickering emulsion were both increased by around 14 fold when the pH-stat lipolysis model was used. However, the results from the TIM-1 system indicated that the bioaccessibilities of PMFs in the nanoemulsion and Pickering emulsion were around two and four times that in bulk oil, respectively. The results from this work would provide valuable information for the rational design and evaluation of lipid-based delivery systems for lipophilic bioactive compounds.

Assessment of dynamic bioaccessibility of curcumin encapsulated in milled starch particle stabilized Pickering emulsions using TNO's gastrointestinal model

Pickering emulsions stabilized by milled starch particles have been developed as a novel food-grade formulation to enhance the bioaccessibility of poorly soluble bioactive compounds (i.e., curcumin) by controlling the digestion of lipids in the human gastrointestinal (GI) tract. The dynamic bioaccessibilities of curcumin with and without encapsulation in the Pickering emulsion were evaluated using the dynamic TNO's gastrointestinal (TIM-1) model. For comparison, their digestion profiles were also studied using the in vitro pH-stat lipolysis model. With the combination of two in vitro models, the effect of the milled starch particle stabilized Pickering emulsions on the bioaccessibility of curcumin was fully revealed. There are large differences between the bioaccessibility values of curcumin samples obtained by these two models. Simulated small intestinal lipolysis in the pH-stat model revealed that the bioaccessibility of curcumin encapsulated in the Pickering emulsion was 27.6%, which was larger than 22.1% for free curcumin suspended in the bulk oil phase. The bioaccessibility of curcumin was 50.7% in the emulsion system and 7.8% in the bulk oil when using the TIM-1 model, which simulated the digestion conditions of the entire human GI tract. The digestion mechanism of the milled starch particle stabilized Pickering emulsions in the upper GI tract was well elucidated by the TIM-1 model. The gradual release and improved dissolution profile of the milled starch particle stabilized Pickering emulsions highlighted their potential as delivery systems for lipophilic bioactive compounds.

Aged citrus peel (chenpi) extract causes dynamic alteration of colonic microbiota in high-fat diet induced obese mice

Aged citrus peels (chenpi) have been used as a dietary supplement for gastrointestinal health maintenance in China.

Stability andin vitrodigestion study of curcumin-encapsulated in different milled cellulose particle stabilized Pickering emulsions

Figurein vitrolipolysis of curcumin encapsulated Pickering emulsions stabilized by milled cellulose.

Improved bioaccessibility of polymethoxyflavones loaded into high internal phase emulsions stabilized by biopolymeric complexes: A dynamic digestion study via TNO's gastrointestinal model

In this work, the bioaccessibility of polymethoxyflavones (PMFs) loaded in high internal phase emulsions (HIPE, ϕ_oil = 0.82) stabilized by whey protein isolate (WPI)-low methoxy pectin (LMP) complexes was evaluated using in vitro lipolysis and dynamic in vitro intestinal digestion studies. PMFs loaded HIPE was prepared by using aqueous dispersion of pre-formed biopolymeric complexes (WPI-LMP, 2:1 ratio) as the external phase and medium chain triglycerides oil (containing PMFs extracted from citrus peel) as the dispersed phase. The in vitro lipolysis study revealed that PMFs in HIPE became bioaccessible much higher than PMFs in medium chain triacylglycerols oil (MCT oil). In addition, by simulating the entire human gastrointestinal (GI) tract, the GI model TIM-1 demonstrated a 5- and 2-fold increase in the total bioaccessibility for two major PMFs encapsulated in HIPE, i.e. tangeretin (TAN) and nobiletin (NOB), respectively, as opposed to PMFs in MCT oil. Together these results from the digestion study showed that the incorporation of a high amount of PMFs into the viscoelastic matrix of HIPE could represent an innovative and effective way to design an oral delivery system. Such a system could be used to control and to improve the delivery of lipophilic bioactive compounds within the different compartments of the digestive tract, especially the human upper GI tract.

Nanoencapsulation of functional food ingredients

Many functional food ingredients are poorly soluble in water, susceptible to chemical degradation, and incompatible with surrounding food matrix. Other issues are related to limited oral bioavailability, unpleasant sensory properties, and poor release profiles. Nanoencapsulation of functional food ingredients can help increase their water solubility/dispersibility in foods and beverages, improve their bioavailability by exhibiting good dose-dependent functionalities, mask undesired flavors/tastes to reduce the adverse effect on mouth-feel, enhance shelf-life and compatibility during production, storage, transportation and utilization of food products, and control release rate or specific delivery environment for better performance on their functionalities. This chapter provides an overview of different delivery systems for different functional food ingredients, the types of materials suitable for wall materials or building blocks of nanocapsules, the fabrication methods to assemble different delivery systems and release these active ingredients under different physiological conditions.

Milk MicroRNAs in Health and Disease

MicroRNAs are small noncoding RNAs responsible for regulating 40% to 60% of gene expression at the posttranscriptional level. The discovery of circulating microRNAs in several biological fluids opened the path for their study as biomarkers and long-range cell-to-cell communication mediators. Their transfer between individuals in the case of blood transfusion, for example, and their high enrichment in milk have sparked the interest for microRNA transfer through diet, especially from mothers to infants during breastfeeding. The extension of such paradigm led to the study of milk microRNAs in the case of cow or goat milk consumption in adults. Here we provide a comprehensive critical review of the key findings surrounding milk microRNAs in human, cow, and goat milk among other species. We discuss the data on their biological properties, their use as disease biomarkers, their transfer between individuals or species, and their putative or verified functions in health and disease of infants and adult consumers. This work is based on all the literature available and integrates all the results, theories, debates, and validation studies available so far on milk microRNAs and related areas of investigations. We critically discuss the limitations and outline future aspects and avenues to explore in this rapidly growing field of research that could impact public health through infant milk formulations or new therapies. We hope that this comprehensive review of the literature will provide insight for all teams investigating milk RNAs' biological activities and help ensure the quality of future reports.

Assembly of Protein-Polysaccharide Complexes for Delivery of Bioactive Ingredients: A Perspective Paper

Protein-polysaccharide complexes can be created in various ways (physical mixing, enzymatic cross-linking, chemical cross-linking, and Maillard reaction), and diverse protein-polysaccharide complexes are generally grouped into non-covalent and covalent complexes. Delivery systems constructed through assembly of protein-polysaccharide complexes (DSAPC) consist of emulsion-based delivery systems, capsule-based delivery systems, molecular complexes, nanogels, core-shell particles, composite nanoparticles, and micelles. DSAPC are effective delivery vehicles in enhancing the overall efficacy of bioactive ingredients, and DSAPC may possess multiple advantages over other delivery vehicles in bioactive ingredient delivery. However, designing and applying DSAPC are still faced with some challenges, such as low loading of bioactive ingredients. Efforts are required to reconsider and improve efficiency of DSAPC in many aspects, such as controlled release and targeted delivery. On the basis of more comprehensive and deeper understandings, DSAPC can be designed more rationally for delivery of bioactive ingredients.

Determination of Tangeretin in Rat Plasma: Assessment of Its Clearance and Absolute Oral Bioavailability

Tangeretin (TAN) is a dietary polymethoxylated flavone that possesses a broad scope of pharmacological activities. A simple high-performance liquid chromatography (HPLC) method was developed and validated in this study to quantify TAN in plasma of Sprague-Dawley rats. The lower limit of quantification (LLOQ) was 15 ng/mL; the intra- and inter-day assay variations expressed in the form of relative standard deviation (RSD) were all less than 10%; and the assay accuracy was within 100 ± 15%. Subsequently, pharmacokinetic profiles of TAN were explored and established. Upon single intravenous administration (10 mg/kg), TAN had rapid clearance (Cl = 94.1 ± 20.2 mL/min/kg) and moderate terminal elimination half-life (t_{1/2 λz} = 166 ± 42 min). When TAN was given as a suspension (50 mg/kg), poor but erratic absolute oral bioavailability (mean value < 3.05%) was observed; however, when TAN was given in a solution prepared with randomly methylated-β-cyclodextrin (50 mg/kg), its plasma exposure was at least doubled (mean bioavailability: 6.02%). It was obvious that aqueous solubility hindered the oral absorption of TAN and acted as a barrier to its oral bioavailability. This study will facilitate further investigations on the medicinal potentials of TAN.

Edible Nanoencapsulation Vehicles for Oral Delivery of Phytochemicals: A Perspective Paper

Edible nanoencapsulation vehicles (ENVs) designed for the delivery of phytochemicals have gained increasing research interest. The major driving force for this trend is the potential bioavailability enhancement effect for phytochemicals when delivered via ENVs. ENVs affect the bioefficacy of phytochemicals by influencing their dispersion and gastrointestinal stability, rate and site of release, transportation efficiency across the endothelial layer, systemic circulation and biodistribution, and regulation of gut microflora. Enhanced bioefficacy can be achieved by rational design of the size, surface property, matrix materials, and compartment structure of ENVs according to properties of phytochemicals. Future investigations may lay particular emphasis on examining the relevance between results gained by in vitro digestion simulations and those obtained via in vivo digestion simulations, structural evolutions of ENVs during digestion and absorption, impacts of ENVs on the metabolism of phytochemicals, and using ENVs for deciphering the reciprocal interactions between phytochemicals and gut microbiota.

Correlation of Emulsion Structure with Cellular Uptake Behavior of Encapsulated Bioactive Nutrients: Influence of Droplet Size and Interfacial Structure

In this study, an in vitro Caco-2 cell culture assay was employed to evaluate the correlation between emulsion structure and cellular uptake of encapsulated β-carotene. After 4 h of incubation, an emulsion stabilized with whey protein isolate showed the highest intracellular accumulation of β-carotene (1.06 μg), followed by that stabilized with sodium caseinate (0.60 μg) and Tween 80 (0.20 μg), which are 13-, 7.5-, and 2.5-fold higher than that of free β-carotene (0.08 μg), respectively. Emulsions with small droplet size (239 ± 5 nm) showed a higher cellular uptake of β-carotene (1.56 μg) than emulsiond with large droplet size (489 ± 9 nm) (0.93 μg) (p < 0.01). The results suggested that delivery in an emulsion significantly improved the cellular uptake of β-carotene and thus potentially its bioavailability; uptake was closely correlated with the interfacial composition and droplet size of emulsions. The findings support the potential for achieving optimal controlled and targeted delivery of bioactive nutrients by structuring emulsions.

Commercial Dairy Cow Milk microRNAs Resist Digestion under Simulated Gastrointestinal Tract Conditions

BACKGROUND

MicroRNAs are small, gene-regulatory noncoding RNA species present in large amounts in milk, where they seem to be protected against degradative conditions, presumably because of their association with exosomes.

OBJECTIVE

We monitored the relative stability of commercial dairy cow milk microRNAs during digestion and examined their associations with extracellular vesicles (EVs).

METHODS

We used a computer-controlled, in vitro, gastrointestinal model TNO intestinal model-1 (TIM-1) and analyzed, by quantitative polymerase chain reaction, the concentration of 2 microRNAs within gastrointestinal tract compartments at different points in time. EVs within TIM-1 digested and nondigested samples were studied by immunoblotting, dynamic light scattering, quantitative polymerase chain reaction, and density measurements.

RESULTS

A large quantity of dairy milk Bos taurus microRNA-223 (bta-miR-223) and bta-miR-125b (∼10⁹-10¹⁰ copies/300 mL milk) withstood digestion under simulated gastrointestinal tract conditions, with the stomach causing the most important decrease in microRNA amounts. A large quantity of these 2 microRNAs (∼10⁸-10⁹ copies/300 mL milk) was detected in the upper small intestine compartments, which supports their potential bioaccessibility. A protocol optimized for the enrichment of dairy milk exosomes yielded a 100,000 × g pellet fraction that was positive for the exosomal markers tumor susceptibility gene-101 (TSG101), apoptosis-linked gene 2-interacting protein X (ALIX), and heat shock protein 70 (HSP70) and containing bta-miR-223 and bta-miR-125b. This approach, based on successive ultracentrifugation steps, also revealed the existence of ALIX^-, HSP70^-/low, and TSG101^-/low EVs larger than exosomes and 2-6 times more enriched in bta-miR-223 and bta-miR-125b (P < 0.05).

CONCLUSIONS

Our findings indicate that commercial dairy cow milk contains numerous microRNAs that can resist digestion and are associated mostly with ALIX^-, HSP70^-/low, and TSG101^-/low EVs. Our results support the existence of interspecies transfer of microRNAs mediated by milk consumption and challenge our current view of exosomes as the sole carriers of milk-derived microRNAs.

Role of dietary bioactive natural products in estrogen receptor-positive breast cancer

Estrogen receptor (ER)-positive breast cancer, including luminal-A and -B, is the most common type of breast cancer. Extended exposure to estrogen is associated with an increased risk of breast cancer. Both ER-dependent and ER-independent mechanisms have been implicated in estrogen-mediated carcinogenesis. The ER-dependent pathway involves cell growth and proliferation triggered by the binding of estrogen to the ER. The ER-independent mechanisms depend on the metabolism of estrogen to generate genotoxic metabolites, free radicals and reactive oxygen species to induce breast cancer. A better understanding of the mechanisms that drive ER-positive breast cancer will help optimize targeted approaches to prevent or treat breast cancer. A growing emphasis is being placed on alternative medicine and dietary approaches toward the prevention and treatment of breast cancer. Many natural products and bioactive compounds found in foods have been shown to inhibit breast carcinogenesis via inhibition of estrogen induced oxidative stress as well as ER signaling. This review summarizes the role of bioactive natural products that are involved in the prevention and treatment of estrogen-related and ER-positive breast cancer.

Improved oral bioavailability of docetaxel by nanostructured lipid carriers: in vitro characteristics, in vivo evaluation and intestinal transport studies

The objective of the current study was to explore the potential of nanostructured lipid carriers (NLC) for oral delivery of docetaxel (DTX) and investigate the absorption mechanismin vivo.

Improving nutraceutical bioavailability using mixed colloidal delivery systems: lipid nanoparticles increase tangeretin bioaccessibility and absorption from tangeretin-loaded zein nanoparticles

The use of a multi-particle delivery system to increase the bioavailability of tangeretin.