Preparation and Characterization of Mucoadhesive Nanoparticles for Enhancing Cellular Uptake of Coenzyme Q10

Antibacterial Lecithin/Chitosan Nanoparticles for the Sustained Release of Ciprofloxacin to Treat Ocular Bacterial Infections

Ocular drug-delivery is one of the most challenging areas owing to nature of ocular tissues. Various nanoformulations have been designed and investigated for drug-delivery to achieve high drug bioavailability. The major focus of these preparations available in market is to utilize nanomaterial as drug-carrier only, with less focus on developing functional-nanomaterials, which is a key knowledge gap in the field. To address this, we developed a nanoparticulate system from bioactive-polymers, having intrinsic antimicrobial and mucoadhesiveness, loaded with ciprofloxacin (cipro) to treat ocular bacterial infections. Cipro-loaded lecithin/chitosan nanoparticles were prepared and characterized for their physiochemical properties. They exhibited good drug loading efficiency and showed sustained drug-release for 72 h, with slow release for first 4 h followed by a burst release in phosphate buffered saline and simulated tear fluid. Cipro-loaded nanoparticles were assessed for their antibacterial potential against Staphylococcus aureus (96 %) and Pseudomonas aeruginosa (72 %) using optical density, disc-diffusion method, live-dead assay, and demonstrated promising antibacterial properties. The drug-loaded nanoparticles showed good cytocompatibility (~90 %) towards murine fibroblasts and rabbit corneal cells. Being amphiphilic in nature, the nanoparticles exhibited mucoadhesiveness, hemocompatibility (<4 %) and, thus, proving to be a promising candidate for treating ocular infections. This approach ensures efficient drug delivery and synergic/additive therapeutic effects.

Advances in micro- and nano- delivery systems for increasing the stability, bioavailability and bioactivity of coenzyme Q10

Coenzyme Q10 acts as a liposoluble quinone compound in mitochondrial oxidative phosphorylation, serving as an electron carrier and protecting the cell membrane structure as an antioxidant. Coenzyme Q10 has notable health benefits, including anti-aging, anti-inflammatory, prevention of cardiovascular diseases, and assistance in cancer treatment. However, its poor water solubility, unstable chemical properties, and low bioavailability significantly limit its application. This article reviewed the design and development processes of various delivery systems for coenzyme Q10, discussing the advantages and disadvantages of different delivery systems and their improvement strategies, including improvements in the stability and accessibility of emulsions, achieving higher penetration rates for oleogels, and reducing the use of toxic substances in the production process of liposomes. The mechanisms behind coenzyme Q10's low stability and bioavailability were analyzed, and the bioactivity and research prospects of coenzyme Q10 were also discussed. In summary, this review offered valuable insights into the design and application of delivery systems for coenzyme Q10, which may provide a reference for its development and application in pharmaceuticals, cosmetics, health products, and other industries in the future.

CoQ10 bioaccessibility and Caco-2 cell uptake improved with novel medium chain triglyceride encapsulation

Coenzyme Q10 (CoQ10) serves as a key component of the electron transport chain. Although it can be produced endogenously, genetic mutations and drugs (e.g., statins) limit the amount absorbed, thus dietary sources provide a supplement. The hydrophobicity of CoQ10 limits its absorption during digestion. Encapsulation with medium chain triglycerides (MCTs) + phospholipid improves the water solubility of CoQ10, but the effect on bioaccessibility and Caco-2 cell uptake is understudied. This study compared the bioaccessibility and Caco-2 cell uptake of a powdered CoQ10 (control), as compared to equivalent doses of CoQ10 (2 mg) provided as ubiquinone encapsulated with MCTs + phospholipid in a VitaDry® and VitaSperse® product. Following sample hydration (for the control and VitaDry®) in vitro digestion was conducted. Samples were extracted and CoQ10 quantitated using high performance liquid chromatography-diode array detection (HPLC-DAD). The Vita encapsulated CoQ10 was 1.4× more bioaccessible as compared to the control, with no difference between the VitaDry® and VitaSperse® products. The VitaDry® and VitaSperse® encapsulated CoQ10 was 6.0× and 5.5× better taken up by Caco-2 cells. This study demonstrates that novel MCT and phospholipid based encapsulated CoQ10 is more bioaccessible, and in vitro results support future studies to establish if it may provide a more bioavailable alternative to CoQ10 alone.

Overcoming Biopotency Barriers: Advanced Oral Delivery Strategies for Enhancing the Efficacy of Bioactive Food Ingredients

Bioactive food ingredients contribute to the promotion and maintenance of human health and wellbeing. However, these functional ingredients often exhibit low biopotency after food processing or gastrointestinal transit. Well-designed oral delivery systems can increase the ability of bioactive food ingredients to resist harsh environments inside and outside the human body, as well as allow for controlled or triggered release of bioactives to specific sites in the gastrointestinal tract or other tissues and organs. This review presents the characteristics of common bioactive food ingredients and then highlights the barriers to their biopotency. It also discusses various oral delivery strategies and carrier types that can be used to overcome these biopotency barriers, with a focus on recent advances in the field. Additionally, the advantages and disadvantages of different delivery strategies are highlighted. Finally, the current challenges facing the development of food-grade oral delivery systems are addressed, and areas where future research can lead to new advances and industrial applications of these systems are proposed.

The Effect of Multilayer Nanoemulsion on the In Vitro Digestion and Antioxidant Activity of β-Carotene

The objectives of this study were to design multilayer oil-in-water nanoemulsions using a layer-by-layer technique to enhance the stability of β-carotene and evaluate its effect on in vitro release and antioxidant activity. To prepare β-carotene-loaded multilayer nanoemulsions (NEs), a primary NE (PRI-NE) using Tween 20 was coated with chitosan (CS) for the secondary NE (SEC-CS), and with dextran sulfate (DS) and sodium alginate (SA) for the two types of tertiary NEs (TER-DS, TER-SA). The multilayer NEs ranged in particle size from 92 to 110 nm and exhibited high entrapment efficiency (92-99%). After incubation in a simulated gastrointestinal tract model, the release rate of free fatty acids decreased slightly after coating with CS, DS, and SA. The bioaccessibility of β-carotene was 7.02% for the PRI-NE, 7.96% for the SEC-CS, 10.88% for the TER-DS, and 10.25% for the TER-SA. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging abilities increased by 1.2 times for the multilayer NEs compared to the PRI-NE. In addition, the cellular antioxidant abilities improved by 1.8 times for the TER-DS (87.24%) compared to the PRI-NE (48.36%). Therefore, multilayer nanoemulsions are potentially valuable techniques to improve the stability, in vitro digestion, and antioxidant activity of β-carotene.

Bioavailability enhancement of coenzyme Q10: An update of novel approaches

Coenzyme Q10 (CoQ10) is an essential, lipid-soluble vitamin involved in electron transport in the oxidoreductive reactions of the mitochondrial respiratory chain. Structurally, the quinone ring is connected to an isoprenoid moiety, which has a high molecular weight. Over the years, coenzyme Q10 has become relevant in the treatment of several diseases, like neurodegenerative disorders, coronary diseases, diabetes, hypercholesterolemia, cancer, and others. According to studies, CoQ10 supplementation might be beneficial in the treatment of CoQ10 deficiencies and disorders associated with oxidative stress. However, the water-insoluble nature of CoQ10 is a major hindrance to successful supplementation. So far, many advancements in CoQ10 bioavailability enhancement have been developed using novel drug carriers such as solid dispersion, liposomes, micelles, nanoparticles, nanoemulsions, self-emulsifying drug systems, or various innovative approaches (CoQ10 complexation with proteins). This article aims to provide an update on methods to improve CoQ10 solubility and bioavailability.

Antiaging properties of antioxidant photoprotective polymeric nanoparticles loaded with coenzyme-Q10

Skin is the most extensive organ within our body. It is continually subjected to stress factors, among which ultraviolet irradiation, a key factor responsible in skin aging since it leads to reactive oxygen species production. In order to fight against these oxidative species, the human body has an innate robust antioxidant mechanism composed of several different substances, one of which is coenzyme Q₁₀. Its capacity to increase cellular energy production and excellent antioxidant properties have been proved, as well as its antiaging properties being able to attenuate cellular damage induced by ultraviolet irradiation in human dermal fibroblasts. However, its high hydrophobicity and photolability hampers its therapeutic potential. In this context, the objective of this work consists of the preparation of chitosan-rosmarinic acid conjugate-based nanoparticles to encapsulate coenzyme Q10 with high encapsulation efficiencies in order to improve its bioavailability and broaden its therapeutic use in skin applications. Hyaluronic acid coating was performed giving stable nanoparticles at physiological pH with 382 ± 3 nm of hydrodynamic diameter (0.04 ± 0.02 polydispersity) and - 18 ± 3 mV of surface charge. Release kinetics studies showed a maximum of 82 % mass release of coenzyme Q₁₀ after 40 min, and radical scavenger activity assay confirmed the antioxidant character of chitosan-rosmarinic acid nanoparticles. Hyaluronic acid-coated chitosan-rosmarinic acid nanoparticles loaded with coenzyme Q₁₀ were biocompatible in human dermal fibroblasts and exhibited interesting photoprotective properties in ultraviolet irradiated cells. In addition, nanoparticles hindered the production of reactive oxygen species, interleukin-6 and metalloproteinase-1, as well as caspase-9 activation maintaining high viability values upon irradiation of dermal fibroblasts. Overall results envision a great potential of these nanovehicles for application in skin disorders or antiaging treatments.

Quercetin delivery characteristics of chitosan nanoparticles prepared with different molecular weight polyanion cross-linkers

The aim of the study was to investigate the effects of cross-linkers on quercetin (QUE) absorption characteristics of QUE-loaded chitosan nanoparticles (CS-NPs). CS-NPs (461.2-482.7 nm) were prepared by ionic gelation at pH 3.5 using tripolyphosphate (367.9 Da), dextran sulfate (>15 kDa), arabic gum (AG, >250 kDa), or hyaluronic acid (HA, >1000 kDa). Mucoadhesion and cell permeation of QUE were significantly increased by positive charged CS-NPs due to interactions with negatively charged mucosal layer. Moreover, CS-AG and CS-HA NPs prepared with relatively higher MW cross-linkers exhibited significantly higher adhesion and permeation than the others. These results were verified by a cellular antioxidant activity assay; CS-AG (137.5 unit) and CS-HA NPs (126.5 unit) showed significantly higher activities after internalization into Caco-2 cells. Therefore, encapsulation within CS-NPs prepared using high MW cross-linkers such as AG and HA is found to be potentially valuable techniques for improving the QUE absorption.

Innovative coenzyme Q10-loaded nanoformulation as an adjunct approach for the management of moderate periodontitis: preparation, evaluation, and clinical study

Periodontal diseases are worldwide chronic inflammatory conditions that are associated with heavy production of reactive oxygen species followed by damage of the tooth-supporting tissues. Although the mechanical approach of scaling and root planing (SRP) for removing of plaque is considered as the key element for controlling periodontitis, the anatomical complexity of the teeth hinders accessibility to deeper points. The aim of this study was to design a micellar nanocarrier of coenzyme Q10 (Q₁₀) to support the management of moderate periodontitis. Q₁₀ was formulated in nanomicelles (NM_Q10) and evaluated regarding encapsulation efficiency, loading efficiency, percent yield, hydrodynamic size (D_h), polydispersity index (PDI), and zeta potential (ζ potential). NM_Q10 was incorporated to in situ gelling systems and the in vitro release of Q₁₀ was studied. A clinical study including evaluation of periodontal parameters and biochemical assay of total antioxidant capacity (T-AOC) and lipid peroxide was achieved. Results revealed that Q₁₀ was efficiently entrapped in spherical-shaped stable NM_Q10 with D_h, PDI, and ζ potential of 154.0 nm, 0.108, and - 31.67 mV, respectively. The clinical study revealed that SRP only exhibited improvement of the periodontal parameters. Also, assay of T-AOC and lipid peroxide revealed that their values diminished by 21.5 and 23.8%, respectively. On the other hand, SRP combined with local application of NM_Q10 resulted in a significant management of the periodontal parameters, and likewise, the assayed biomarkers proved enhanced antioxidant activity over SRP alone. In conclusion, NM_Q10 can be suggested as a promising nanosystem as an approach to support the management of chronic periodontitis. Such results could be used to conduct larger clinical studies. Graphical abstrac.

Evaluation of photostability and phototoxicity of esterified derivatives of ubiquinol-10 and their application as prodrugs of reduced coenzyme Q10 for topical administration

Ubiquinol-10 (UqH-10), the fully reduced form of ubiquinone-10 (Uq-10, coenzyme Q₁₀ ), is an antioxidant and is involved in energy production. However, physicochemical disadvantages, such as rapid oxidation, water-insolubility, photoinstability, and phototoxicity, limit its application. We previously reported that UqH-10 1,4-bis-N,N-dimethylglycinate improved the oxidation susceptibility and poor bioavailability of UqH-10 in rats. Herein, we evaluated the photochemical properties of UqH-esterified derivatives (N,N-dimethylglycinate, hemi-succinate, ethylsuccinate, and hemi-glutarate). Photostability was examined by irradiation using artificial sunlight and monochromatic light. The concentration of each compound was determined using LC-MS/MS. Phototoxicity was assessed by singlet oxygen and superoxide assays. Delivery of UqH-10 via UqH-esters to the HaCaT human keratinocyte cell line was determined using LC-MS/MS. UqH-esters showed higher photostability to artificial sunlight than Uq-10 and UqH-10. Uq-10 and UqH-10 were rapidly degraded by monochromatic light at 279 nm, whereas UqH-esters were more stable. UVA and/or UVB irradiation generated high levels of singlet oxygen and superoxide in Uq-10, whereas UqH-esters were unreactive. Additionally, UqH-esters effectively delivered UqH-10 to HaCaT cells following efficient uptake in their ester forms and ester bond hydrolysis in the cells. In conclusion, UqH-ester derivatives exhibit higher photostability and lower phototoxicity compared with Uq-10 and UqH-10.

Dendrimer-like glucan nanoparticulate system improves the solubility and cellular antioxidant activity of coenzyme Q10

Aqueous coenzyme Q10 (CoQ10) dispersions were prepared using sugary maize dendrimer-like glucan (SMDG) with solid-dispersion treatment. After measuring solubility, recovery rate and loading rate, the initial weight ratio of CoQ10:SMDG was optimized to be 1:27, with the solubility markedly increasing up 188.8-folds compared to pure CoQ10 solution. The structural characterizations of CoQ10-SMDG formulation showed crystal CoQ10 was entrapped in SMDG matrix for amorphous state, associated with the strong interactions with glucan chains. The antioxidant activity of CoQ10-SMDG was assessed via DPPH and FRAP assay. DPPH scavenging activity and FRAP value of it were as high as 95.1% and 0.87 mM, respectively. The cellular uptake of CoQ10 in CoQ10-SMDG group was significantly higher than that of natural CoQ10. CoQ10-SMDG also exhibited significant protective effects against cellular damage in H₂O₂-induced HaCaT cell model. The results indicated that dendrimer-like glucan is an excellent platform to encapsulate and improve biological activity of hydropholic compounds.

Genes and lipids that impact uptake and assimilation of exogenous coenzyme Q in Saccharomyces cerevisiae

Coenzyme Q (CoQ) is an essential player in the respiratory electron transport chain and is the only lipid-soluble antioxidant synthesized endogenously in mammalian and yeast cells. In humans, genetic mutations, pathologies, certain medical treatments, and aging, result in CoQ deficiencies, which are linked to mitochondrial, cardiovascular, and neurodegenerative diseases. The only strategy available for these patients is CoQ supplementation. CoQ supplements benefit a small subset of patients, but the poor solubility of CoQ greatly limits treatment efficacy. Consequently, the efficient delivery of CoQ to the mitochondria and restoration of respiratory function remains a major challenge. A better understanding of CoQ uptake and mitochondrial delivery is crucial to make this molecule a more efficient and effective therapeutic tool. In this study, we investigated the mechanism of CoQ uptake and distribution using the yeast Saccharomyces cerevisiae as a model organism. The addition of exogenous CoQ was tested for the ability to restore growth on non-fermentable medium in several strains that lack CoQ synthesis (coq mutants). Surprisingly, we discovered that the presence of CoQ biosynthetic intermediates impairs assimilation of CoQ into a functional respiratory chain in yeast cells. Moreover, a screen of 40 gene deletions considered to be candidates to prevent exogenous CoQ from rescuing growth of the CoQ-less coq2Δ mutant, identified six novel genes (CDC10, RTS1, RVS161, RVS167, VPS1, and NAT3) as necessary for efficient trafficking of CoQ to mitochondria. The proteins encoded by these genes represent essential steps in the pathways responsible for transport of exogenously supplied CoQ to its functional sites in the cell, and definitively associate CoQ distribution with endocytosis and intracellular vesicular trafficking pathways conserved from yeast to human cells.

Metabolism of the Flavonol Kaempferol in Kidney Cells Liberates the B-ring to Enter Coenzyme Q Biosynthesis

Coenzyme Q (CoQ) is an essential component of the mitochondrial electron transport chain and an important antioxidant present in all cellular membranes. CoQ deficiencies are frequent in aging and in age-related diseases, and current treatments are limited to CoQ supplementation. Strategies that rely on CoQ supplementation suffer from poor uptake and trafficking of this very hydrophobic molecule. In a previous study, the dietary flavonol kaempferol was reported to serve as a CoQ ring precursor and to increase the CoQ content in kidney cells, but neither the part of the molecule entering CoQ biosynthesis nor the mechanism were described. In this study, kaempferol labeled specifically in the B-ring was isolated from Arabidopsis plants. Kidney cells treated with this compound incorporated the B-ring of kaempferol into newly synthesized CoQ, suggesting that the B-ring is metabolized via a mechanism described in plant cells. Kaempferol is a natural flavonoid present in fruits and vegetables and possesses antioxidant, anticancer, and anti-inflammatory therapeutic properties. A better understanding of the role of kaempferol as a CoQ ring precursor makes this bioactive compound a potential candidate for the design of interventions aiming to increase endogenous CoQ biosynthesis and may improve CoQ deficient phenotypes in aging and disease.

A New Food-grade Coenzyme Q10 Formulation Improves Bioavailability: Single and Repeated Pharmacokinetic Studies in Healthy Volunteers

BACKGROUND

Coenzyme Q10 is a fundamental endogenous factor involved in cell energy production that shows protective properties in oxidative stress, mainly in skeletal and heart muscle. Coenzyme Q10 supplementation appears to benefit athletes in strenuous training and in the elderly, demonstrating ant-inflammatory properties by reducing inflammatory cytokines. Improved absorption of coenzyme Q10 via a new delivery system would represent an important step forward in the use of coenzyme Q10 as a dietary supplement.

OBJECTIVE

The aim of the study was to evaluate the solubility and oral absorption in human healthy volunteers of a new food grade coenzyme Q10 phytosome formulation.

METHODS

Solubility studies were performed in vitro in simulated gastrointestinal fluids; human studies were conducted in healthy volunteers to evaluate oral absorption in a Single dose study, in comparison with the coenzyme Q10 capsules, and in a repeated study at two increasing doses.

RESULTS

The highest solubility shown by coenzyme Q10 phytosome in simulated intestinal fluids results in an improvement in oral absorption of coenzyme Q10 in healthy volunteers, three times more than the coenzyme Q10 according to AUC (area under the time/concentration curve) values. When two increasing doses (one and two capsules) were administered to healthy volunteers within a two-week schedule, the plasmatic levels of coenzyme Q10 resulted in 0.864±0.200 μg/ml (Mean±S.D.+41%) and 1.321±0.400 μg/ml (+116%), respectively versus baseline (0.614±0.120 μg/ml one capsule, 0.614±0.160 μg/ml two capsules). This detected dose-related bioavailability of coenzyme Q10 phytosome was even observed with no alterations in vital signs, neither in the physical examination nor in ECG, and no changes of clinical and biochemical parameters were observed.

CONCLUSION

These findings, taken together, support the safety profile and significantly improved coenzyme Q10 oral absorption in humans with this new phytosome delivery formulation.

Preparation and evaluation of a Rubropunctatin-loaded liposome anticancer drug carrier

Rubropunctatin is a naturally occurring constituent of polyketide compounds that has great potential in the development of cancer-assisted chemotherapy. However, it has certain shortcomings such as water insolubility and photo instability that limit its clinical application. In this study, we constructed a Rubropunctatin-loaded liposome (R-Liposome) anticancer drug carrier for the first time. The results indicate that R-Liposome is water soluble, has spherical morphology, great homogeneity and dispersibility with high encapsulation efficiency (EE%, 90 ± 3.5%) and loading rate (LR%, 5.60 ± 2.5%) values. Moreover, the carrier improves the photostability, storage and pH stabilities of Rubropunctatin. The R-Liposome also prolongs the release of Rubropunctatin, enhances the anticancer activity of Rubropunctatin and encourages the mechanism of Rubropunctatin to promote apoptosis. Therefore, liposomal nanoparticles have great potential as drug delivery vehicles of Rubropunctatin for cancer treatment.

Green Formulation of Triglyceride/Phospholipid-Based Nanocarriers as a Novel Vehicle for Oral Coenzyme Q10 Delivery

This study was aimed to develop a novel nanocarrier for coenzyme Q10 (CoQ10) by a green process that prevented the use of surfactants and organic solvents. Triglyceride/phospholipid-based nanocarriers were developed through high-pressure homogenization (an industrial feasible process), and a 2^5-1 fractional factorial design was adopted to assess the influences of formulation variables on the considered responses, including vesicle size, entrapment efficiency, loading capacity, and solubility of the vehicles in simulated gastrointestinal fluids. The optimized formulation was further in-depth characterized in terms of morphology, release behavior, biocompatibility (Caco-2 cell cytotoxicity and histological examination), thermal behavior, and Fourier transform infrared analysis. Optimal nanocarriers were found to have mean particle size of 75 nm, narrow particle distribution, and CoQ10 entrapment of 95%. The optimized formulation was stable upon incubation in simulated gastrointestinal fluids without considerable leakage of cargo, which was in agreement with their sustained release behavior. Microscopic observations also confirmed nanosized nature of the vesicles and revealed their spherical shape. Moreover, toxicity evaluations at the cellular and tissue levels revealed their nontoxic nature. In conclusion, triglyceride/phospholipid-based nanocarriers proved to be a green safe vehicle for delivery of CoQ10 with industrial-scale production capability and could provide a new horizon for delivery of hydrophobic nutraceuticals. PRACTICAL APPLICATION: Green nanostructure formulation approaches have recently gained tremendous attraction for their safe profile especially when it comes to supplements, which are generally recommended for daily use. However, their sufficient association with cargoes and industrial-scale production have remained considerable challenges. This study focuses on the development of lipid-based nanocarriers for CoQ10 by an industrial feasible process that prevents the use of any surfactants or organic solvents.

Mucoadhesive Chitosan-Gum Arabic Nanoparticles Enhance the Absorption and Antioxidant Activity of Quercetin in the Intestinal Cellular Environment

Quercetin (QUE)-loaded nanoparticles (QCG-NPs) were fabricated by ionic gelation between chitosan (CS) and gum arabic (GA) at pH 3.5. At constant CS (0.5 mg/mL) and QUE (60 μM) concentrations, QCG-NPs (260-490 nm) were prepared uniformly with 0.8-2.2 mg/mL GA and exhibited high QUE encapsulation efficiency (94.8-98.0%) and sustained QUE release (4.42-8.89% after 8 h). Because of the electrostatic interaction between QCG-NPs and the mucin layer, in vitro mucin and cell adhesion of QUE were significantly (p < 0.05) enhanced in QCG-NPs (0.44-0.48 mg/mL and 31.7-78.5%), respectively, and the adhesiveness was significantly (p < 0.05) increased with an increase of GA. Because particle size and adhesion properties affect the surface area and retention time of QCG-NPs at the absorption site, cell permeation of QUE through simple diffusion by QCG-NPs exhibited the same tendency as the adhesion results. These data were verified in cellular antioxidant and in vivo ferric reducing abilities of plasma assays that evaluated the antioxidant activities of QUE absorbed into an intestinal cell model and rat blood, respectively. The results provide a better understanding of QCG-NP absorption and indicate that QCG-NPs with mucoadhesion properties can be an effective delivery system for improving QUE absorption.