Improved photostability and cytotoxic effect of coenzyme Q10 by its association with vitamin E acetate in polymeric nanocapsules

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.

Auxiliary effect of trolox on coenzyme Q10 restricts angiogenesis and proliferation of retinoblastoma cells via the ERK/Akt pathway

Reactive oxygen species (ROS) are essential for cancer signalling pathways and tumour maintenance, making ROS targeting a promising anti-cancer strategy. Coenzyme Q10 (CoQ10) has been shown to be effective against various cancers, but its impact on retinoblastoma, alone or with trolox, remains unreported. Cytotoxicity of CoQ10 alone and with trolox was evaluated in normal human retinal pigment epithelium cells (ARPE-19) and Y79 retinoblastoma cells using CCK-8. Flow cytometry was used to assess apoptosis, cell cycle, ROS, and mitochondrial membrane potential (MMP). Anti-angiogenic potential was tested using human umbilical vein endothelial cells (HUVECs) and chick chorioallantoic membrane (CAM) assays. Mechanistic studies were conducted via RT-PCR and western blotting. CoQ10, alone and with trolox, reduced Y79 cell viability, induced apoptosis through excess ROS generation, and decreased MMP significantly. Both treatments caused G2/M phase cell arrest. The CAM assay showed a significant reduction in endothelial cell proliferation, evidenced by fewer number of co-cultured HUVECs when exposed to CoQ10 or CoQ10 with trolox. The combination of CoQ10 and trolox significantly reduced VEGF-A, ERK, and Akt receptor levels, while CoQ10 alone significantly inhibited ERK and Akt phosphorylation. Together, CoQ10 and trolox reduced protein expression of VEGFA. CoQ10 alone and with trolox, induces apoptosis in Y79 retinoblastoma cells by inhibiting the ERK/Akt pathway and downregulating VEGFA. This study is the first to report the in vitro and in-ovo anti-cancer potential of CoQ10 alone or when combined with trolox, on human retinoblastoma Y79 cells.

Diazepam nanocapsules as an alternative for sleep induction: Development study and toxicity assessment

Diazepam (DZP) is a sedative medication prescribed to treat anxiety and as a sleep inducer, although its residual effects are unfavorable to patients. Nanotechnology represents a tool to improve the pharmacological characteristics of drugs, reducing their side effects. This study aimed to develop and characterize DZP nanocapsules and to evaluate their toxicity in alternative models and the hypnotic-sedative effect in mice. Nanocapsules were prepared by the nanoprecipitation method and properly characterized. Long-term and accelerated stability studies were performed. The in vitro release profile was determined by diffusion in Franz cells. The safety of the formulation was evaluated in the Caenorhabditis elegans (C. elegans) and the oral acute toxicity in mice. Pharmacological evaluation was performed using thiopental-induced sleeping time. DZP was successfully incorporated into Poly-(ɛ-caprolactone) (PCL) nanocapsules, with high entrapment efficiency. The nanocapsule did not affect the development or survival of C. elegans, different from the free drug, which affected the nematode development at the higher tested dose. No signs of toxicity, nor body mass or feed consumption changes were observed during the 14 days evaluated. Finally, this innovative formulation carrying DZP can produce a hypnotic-effect at a reduced dose compared to the free drug, with no toxicity in alternative models.

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.

The role of coenzyme Q10 as a preventive and therapeutic agent for the treatment of cancers

Currently, several options are available for the prevention and treatment of cancers; however, many limitations remain with these approaches. Recently, antioxidants have become important preventive and therapeutic alternatives with few adverse events and minimum cost. Coenzyme Q10 (CoQ10) is a naturally occurring component that performs an anticancer function by reducing oxidative stress. CoQ10 supplementation as an adjuvant therapy offers more progress in the elimination and development of cancers. This review aimed to critically assess and summarize the implication of CoQ10 in cancers, highlighting possible mechanisms, and future directions of research for the standardization of the current regimen for cancer prevention and treatment.

Karaya/Gellan-Gum-Based Bilayer Films Containing 3,3'-Diindolylmethane-Loaded Nanocapsules: A Promising Alternative to Melanoma Topical Treatment

This study aimed to incorporate nanocapsules containing 3,3'-diindolylmethane (DIM) with antitumor activity into a bilayer film of karaya and gellan gums for use in topical melanoma therapy. Nanocarriers and films were prepared by interfacial deposition of the preformed polymer and solvent casting methods, respectively. Incorporating DIM into nanocapsules increased its antitumor potential against human melanoma cells (A-375) (IC50 > 24.00 µg/mL free DIM × 2.89 µg/mL nanocapsules). The films were transparent, hydrophilic (θ < 90°), had homogeneous thickness and weight, and had a DIM content of 106 µg/cm2. Radical ABTS+ scavenger assay showed that the DIM films presented promising antioxidant action. Remarkably, the films showed selective bioadhesive potential on the karaya gum side. Considering the mechanical analyses, the nanotechnology-based films presented appropriate behavior for cutaneous application and controlled DIM release profile, which could increase the residence time on the application site. Furthermore, the nanofilms were found to increase the permeation of DIM into the epidermis, where melanoma develops. Lastly, the films were non-hemolytic (hemolysis test) and non-irritant (HET-CAM assay). In summary, the combination of karaya and gellan gum in bilayer films that contain nanoencapsulated DIM has demonstrated potential in the topical treatment of melanoma and could serve as a viable option for administering DIM for cutaneous melanoma therapy.

Exploring the potential of intranasally administered naturally occurring quercetin loaded into polymeric nanocapsules as a novel platform for the treatment of anxiety

Anxiety is one of the most prevalent forms of psychopathology that affects millions worldwide. It gained more importance under the pandemic status that resulted in higher anxiety prevalence. Anxiolytic drugs such as benzodiazepines have an unfavorable risk/benefit ratio resulting in a shift toward active ingredients with better safety profile such as the naturally occurring quercetin (QRC). The delivery of QRC is hampered by its low water solubility and low bioavailability. The potential to enhance QRC delivery to the brain utilizing polymeric nanocapsules administered intranasally is investigated in the current study. Polymeric nanocapsules were prepared utilizing the nanoprecipitation technique. The best formula displayed a particle size of 227.8 ± 11.9 nm, polydispersity index of 0.466 ± 0.023, zeta potential of - 17.5 ± 0.01 mV, and encapsulation efficiency % of 92.5 ± 1.9%. In vitro release of QRC loaded polymeric nanocapsules exhibited a biphasic release with an initial burst release followed by a sustained release pattern. Behavioral testing demonstrated the superiority of QRC loaded polymeric nanocapsules administered intranasally compared to QRC dispersion administered both orally and intranasally. The prepared QRC loaded polymeric nanocapsules also demonstrated good safety profile with high tolerability.

A reactive oxygen species-responsive hydrogel encapsulated with bone marrow derived stem cells promotes repair and regeneration of spinal cord injury

Spinal cord injury (SCI) is an overwhelming and incurable disabling event accompanied by complicated inflammation-related pathological processes, such as excessive reactive oxygen species (ROS) produced by the infiltrated inflammatory immune cells and released to the extracellular microenvironment, leading to the widespread apoptosis of the neuron cells, glial and oligodendroctyes. In this study, a thioketal-containing and ROS-scavenging hydrogel was prepared for encapsulation of the bone marrow derived mesenchymal stem cells (BMSCs), which promoted the neurogenesis and axon regeneration by scavenging the overproduced ROS and re-building a regenerative microenvironment. The hydrogel could effectively encapsulate BMSCs, and played a remarkable neuroprotective role in vivo by reducing the production of endogenous ROS, attenuating ROS-mediated oxidative damage and downregulating the inflammatory cytokines such as interleukin-1 beta (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), resulting in a reduced cell apoptosis in the spinal cord tissue. The BMSCs-encapsulated ROS-scavenging hydrogel also reduced the scar formation, and improved the neurogenesis of the spinal cord tissue, and thus distinctly enhanced the motor functional recovery of SCI rats. Our work provides a combinational strategy against ROS-mediated oxidative stress, with potential applications not only in SCI, but also in other central nervous system diseases with similar pathological conditions.

Nutritional Interventions for Patients with Melanoma: From Prevention to Therapy-An Update

Melanoma is an aggressive skin cancer, whose incidence rates have increased over the past few decades. Risk factors for melanoma are both intrinsic (genetic and familiar predisposition) and extrinsic (environment, including sun exposure, and lifestyle). The recent advent of targeted and immune-based therapies has revolutionized the treatment of melanoma, and research is focusing on strategies to optimize them. Obesity is an established risk factor for several cancer types, but its possible role in the etiology of melanoma is controversial. Body mass index, body surface area, and height have been related to the risk for cutaneous melanoma, although an 'obesity paradox' has been described too. Increasing evidence suggests the role of nutritional factors in the prevention and management of melanoma. Several studies have demonstrated the impact of dietary attitudes, specific foods, and nutrients both on the risk for melanoma and on the progression of the disease, via the effects on the oncological treatments. The aim of this narrative review was to summarize the main literature results regarding the preventive and therapeutic role of nutritional schemes, specific foods, and nutrients on melanoma incidence and progression.

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.

Ethosomes for Coenzyme Q10 Cutaneous Administration: From Design to 3D Skin Tissue Evaluation

Ethosome represents a smart transdermal vehicle suitable for solubilization and cutaneous application of drugs. Coenzyme Q10 is an endogenous antioxidant whose supplementation can counteract many cutaneous disorders and pathologies. In this respect, the present study describes the production, characterization, and cutaneous protection of phosphatidylcholine based ethosomes as percutaneous delivery systems for coenzyme Q10. CoQ10 entrapment capacity in ethosomes was almost 100%, vesicles showed the typical 'fingerprint' structure, while mean diameters were around 270 nm, undergoing an 8% increase after 3 months from production. An ex-vivo study, conducted by transmission electron microscopy, could detect the uptake of ethosomes in human skin fibroblasts and the passage of the vesicles through 3D reconstituted human epidermis. Immunofluorescence analyses were carried on both on fibroblasts and 3D reconstituted human epidermis treated with ethosomes in the presence of H2O2 as oxidative stress challenger, evaluating 4-hydroxynonenal protein adducts which is as a reliable biomarker for oxidative damage. Notably, the pretreatment with CoQ10 loaded in ethosomes exerted a consistent protective effect against oxidative stress, in both models, fibroblasts and in reconstituted human epidermis respectively.

Antitumor action of diphenyl diselenide nanocapsules: In vitro assessments and preclinical evidence in an animal model of glioblastoma multiforme

BACKGROUND

Gliomas are the most aggressive malignant tumors of the central nervous system. The diphenyl diselenide [(PhSe)₂] is an organoselenium compound that has multiple pharmacological properties. Previous reports showed that (PhSe)₂ nanoencapsulation potentiates its in vitro antitumoral action and reduces its toxicity.

OBJECTIVE

In this sense, the current study was designed to further evaluate the (PhSe)₂ antitumoral effect by a set of in vitro techniques using a glioma cell line as well as by an animal model of gliobastoma.

METHODS

For the in vitro tests, the cell viability, propidium iodide uptake and nitrite levels of rat glioma C6 cells were determined after incubation with free (PhSe)₂ or (PhSe)₂-loaded nanocapsules (NC). The glioblastoma model was induced by implantation of C6 glioma cells in the right striatum of rats. Following, animals were submitted to a repeated intragastric administration treatment with (PhSe)₂ or NC (PhSe)₂ (1 mg/kg/day for 15 days) to assess the possible antitumor effect.

MAIN FINDINGS

Both compound forms decreased the C6 glioma cells viability without causing any effect in astrocytes cells (healthy control). Importantly, the NC (PhSe)₂ had superior cytotoxic effect than its free form and increased the nitrite content. Independent of the (PhSe)₂ forms, the intragastric treatment reduced brain tumor size and caused neither alteration in the plasma renal and hepatic markers of function nor in the parameters of oxidative balance in brain, liver and kidneys.

PRINCIPAL CONCLUSIONS

The (PhSe)₂ nanoencapsulation improved its cytotoxic effect against C6 glioma cells and both compound forms attenuated the tumor development.

Incorporation of 3,3'-Diindolylmethane into Nanocapsules Improves Its Photostability, Radical Scavenging Capacity, and Cytotoxicity Against Glioma Cells

3,3'-Diindolylmethane (DIM) is a phytochemical that presents health benefits (antitumor, antioxidant, and anti-inflammatory effects). However, it is water insoluble and thermo- and photolabile, restraining its pharmaceutical applications. As a strategy to overcome such limitations, this study aimed the development and characterization of DIM-loaded nanocapsules (NCs) prepared with different compositions as well as the in vitro assessment of scavenging activity and cytotoxicity. The formulations were obtained using the interfacial deposition of preformed polymer method and were composed by Eudragit® RS100 or ethylcellulose as polymeric wall and primula or apricot oil as the core. All the formulations had adequate physicochemical characteristics: nanometric size (around 190 nm), low polydispersity index (< 0.2), pH value at acid range, high values of zeta potential, drug content, and encapsulation efficiency (~ 100%). Besides, nanoencapsulation protected DIM against UVC-induced degradation and increased the scavenging activity assessed by the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) and 1-1-diphenyl-2-picrylhydrazyl methods. The developed DIM-loaded nanocapsules were further evaluated regarding the in vitro release profile and cytotoxicity against a human glioblastoma cell line (U87 cells). The results demonstrated that the nanoencapsulation promoted a sustained release of the bioactive compound (in the range of 58-78% after 84 h) in comparison to its free form (86% after 12 h), as well as provided a superior cytotoxic effect against the U87 cells in the highest concentrations. Therefore, our results suggest that nanoencapsulation could be a promising approach to overcome the DIM physicochemical limitations and potentialize its biological properties.