Comparing the stability of retinol in liposomes with cholesterol, β-sitosterol, and stigmasterol

Preparation, physicochemical evaluation and in vitro toxicity studies of HSPC and HSPC:DMPC stigmasterol-loaded liposomes

Phytosterols, like stigmasterol, have been studied for their antioxidant, immunomodulatory, and anticancer properties. However, their lipophilic nature and biological instability make it challenging to incorporate them in food supplements and medicinal products. Liposomes offer many benefits in sterols' entrapment and delivery them due to their high bioavailability, low toxicity, and ability to target specific tissues. The purpose of this study was to develop stigmasterol-loaded liposomes using HSPC (Hydrogenated Soy Phosphatidylcholine) and HSPC:DMPC (Dimyristoylphosphatidylcholine). The impact of increasing stigmasterol concentrations on the physicochemical stability of the liposomal formulations was analyzed by dynamic light scattering. The results showed that HSPC-based liposomes could incorporate higher amounts of stigmasterol compared to the HSPC:DMPC-based liposomes. Further analysis through differential scanning calorimetry revealed the formation of metastable phases in HSPC:DMPC:stigmasterol lipid bilayers. Finally, an in vitro MTS assay on HEK-293 cells demonstrated the low toxicity of the stigmasterol-loaded nanoplatforms. In conclusion, stigmasterol, not only contributed to the stability of liposomal formulation but exhibited low cell toxicity on HEK-293 line and could be used as a valuable compound in liposomal drug delivery formulation.

Emerging encapsulation strategies for vitamin A fortification in food sector: an overview

Micro- and nano-encapsulation techniques, such as microfluidization, spray drying, and centrifugal extrusion, have been widely utilized in various industries, including pharmaceuticals, food, cosmetics, and agriculture, to improve the stability, shelf life, and bioavailability of active ingredients, such as vitamin A. Emulsion-based delivery platforms offer feasible and appropriate alternatives for safeguarding, encapsulating, and transporting bioactive compounds. Therefore, there is a need to enrich our basic diet to prevent vitamin A deficiency within a population. This review focused on addressing vitamin A shortages, encapsulation techniques for improving the delivery of vital vitamins A and their food applications. Additionally, more studies are required to guarantee the security of nano-delivery strategies, as they proliferate in the food and beverage sector.

Graphical Abstract

Topical retinoids: Novel derivatives, nano lipid-based carriers, and combinations to improve chemical instability and skin irritation

BACKGROUND

Retinoids, defined as synthetic or natural derivatives of vitamin A, have been extensively studied as anti-aging molecules that are widely applied in cosmetics. However, due to their physicochemical property, retinoids are highly unstable and extremely sensitive to light, oxygen, and temperature. Moreover, topical application of retinoids often leads to cutaneous irritation. These instabilities and irritant properties of retinoids limit their application in cosmetic and pharmaceutical products.

AIM

Our study aimed to provide a systematic review to summarize the mechanisms underlying the instability and irritant properties of retinoids, as well as recent developments in addressing these challenges.

METHODS

A comprehensive PubMed search was conducted using the following keywords: retinoids, chemical instability, skin irritation, retinoid derivatives, nano lipid-based carriers, liposomes, penetration-enhancer vesicles, ethosomes, niosomes, nanoemulsions, solid lipid nanoparticles, vitamins, soothing and hydrating agents, antioxidants and metal chelator and retinol combinations. Relevant researches published between 1968 and 2023 and studies related to these reports were reviewed.

RESULTS

The development of new retinoid derivatives, the utilization of new delivery systems like nano lipid-based carriers and the combination with other compounds like vitamins, soothing agents, antioxidants and metal chelator have been explored to improve the stability, bioavailability, and toxicity of the retinoid family.

CONCLUSIONS

Through advancements in formulation techniques, structure modification of retinoid derivatives and development of novel nano lipid-based carriers, the chemical instability and skin irritation of retinoids has been mitigated, ensuring their efficacy and potency over extended periods.

Food liposomes: Structures, components, preparations, and applications

This review explores liposomes, focusing on their structure, components, the characteristics influencing their stability and applicability in foods, and preparation methods. The role of phospholipids and liposome modulators in preparing liposomes of desired structure and size is emphasized. The potential of liposomes to enhance food value through liposomal encapsulation and delivery of functional substances is reviewed. Conventional and advanced liposome preparation methods are reviewed, underscoring their impact on the marketability of liposomes. The review highlights the need for research into lecithin properties and modulators that enhance liposome stability. The need to develop cost-effective and rapid liposome preparation methods is identified as a key factor in improving the marketability of food liposomes and promoting their use in foods.

Enzymes for dermatological use

Skin is the ultimate barrier between body and environment and prevents water loss and penetration of pathogens and toxins. Internal and external stressors, such as ultraviolet radiation (UVR), can damage skin integrity and lead to disorders. Therefore, skin health and skin ageing are important concerns and increased research from cosmetic and pharmaceutical sectors aims to improve skin conditions and provide new anti-ageing treatments. Biomolecules, compared to low molecular weight drugs and cosmetic ingredients, can offer high levels of specificity. Topically applied enzymes have been investigated to treat the adverse effects of sunlight, pollution and other external agents. Enzymes, with a diverse range of targets, present potential for dermatological use such as antioxidant enzymes, proteases and repairing enzymes. In this review, we discuss enzymes for dermatological applications and the challenges associated in this growing field.

Phytosterol-mediated glycerosomes combined with peppermint oil enhance transdermal delivery of lappaconitine by modulating the lipid composition of the stratum corneum

Although the introduction of glycerosomes has enriched strategies for efficient transdermal drug delivery, the inclusion of cholesterol as a membrane stabilizer has limited their clinical application. The current study describes the development and optimization of a new type of glycerosome (S-glycerosome) that is formed in glycerol solution with β-sitosterol as the stabilizer. Moreover, the transdermal permeation properties of lappaconitine (LA)-loaded S-glycerosomes and peppermint oil (PO)-mediated S-glycerosomes (PO-S-glycerosomes) are evaluated, and the lipid alterations in the stratum corneum are analyzed via lipidomics. The LA-loaded S-glycerosomes prepared by the preferred formulation from the uniform design have a mean size of 145.3 ± 7.81 nm and an encapsulation efficiency of 73.14 ± 0.35%. Moreover, the addition of PO positively impacts transdermal flux, peaking at 0.4% (w/v) PO. Tracing of the fluorescent probe P4 further revealed that PO-S-glycerosomes penetrate deeper into the skin than S-glycerosomes and conventional liposomes. Additionally, treatment with PO-S-glycerosomes alters the isoform type, number, and composition of sphingolipids, glycerophospholipids, glycerolipids, and fatty acids in the stratum corneum, with the most notable effect observed for ceramides, the main component of sphingolipids. Furthermore, the transdermal administration of LA-loaded PO-S-glycerosomes improved the treatment efficacy of xylene-induced inflammation in mice without skin irritation. Collectively, these findings demonstrate the feasibility of β-sitosterol as a stabilizer in glycerosomes. Additionally, the inclusion of PO improves the transdermal permeation of S-glycerosomes, potentially by altering the stratum corneum lipids.

Research Progress of Protein-Based Bioactive Substance Nanoparticles

Bioactive substances exhibit various physiological activities-such as antimicrobial, antioxidant, and anticancer activities-and have great potential for application in food, pharmaceuticals, and nutraceuticals. However, the low solubility, chemical instability, and low bioavailability of bioactive substances limit their application in the food industry. Using nanotechnology to prepare protein nanoparticles to encapsulate and deliver active substances is a promising approach due to the abundance, biocompatibility, and biodegradability of proteins. Common protein-based nanocarriers include nano-emulsions, nano-gels, nanoparticles, and nano complexes. In this review, we give an overview of protein-based nanoparticle fabrication methods, highlighting their pros and cons. Additionally, we discuss the applications and current issues regarding the utilization of protein-based nanoparticles in the food industry. Finally, we provide perspectives on future development directions, with a focus on classifying bioactive substances and their functional properties.

Lipid-based nanoparticles as drug delivery systems for cancer immunotherapy

Immune checkpoint inhibitors (ICIs) have shown remarkable success in cancer treatment. However, in cancer patients without sufficient antitumor immunity, numerous data indicate that blocking the negative signals elicited by immune checkpoints is ineffective. Drugs that stimulate immune activation-related pathways are emerging as another route for improving immunotherapy. In addition, the development of nanotechnology presents a promising platform for tissue and cell type-specific delivery and improved uptake of immunomodulatory agents, ultimately leading to enhanced cancer immunotherapy and reduced side effects. In this review, we summarize and discuss the latest developments in nanoparticles (NPs) for cancer immuno-oncology therapy with a focus on lipid-based NPs (lipid-NPs), including the characteristics and advantages of various types. Using the agonists targeting stimulation of the interferon genes (STING) transmembrane protein as an exemplar, we review the potential of various lipid-NPs to augment STING agonist therapy. Furthermore, we present recent findings and underlying mechanisms on how STING pathway activation fosters antitumor immunity and regulates the tumor microenvironment and provide a summary of the distinct STING agonists in preclinical studies and clinical trials. Ultimately, we conduct a critical assessment of the obstacles and future directions in the utilization of lipid-NPs to enhance cancer immunotherapy.

Current Applications of Liposomes for the Delivery of Vitamins: A Systematic Review

Liposomes have been used for several decades for the encapsulation of drugs and bioactives in cosmetics and cosmeceuticals. On the other hand, the use of these phospholipid vesicles in food applications is more recent and is increasing significantly in the last ten years. Although in different stages of technological maturity-in the case of cosmetics, many products are on the market-processes to obtain liposomes suitable for the encapsulation and delivery of bioactives are highly expensive, especially those aiming at scaling up. Among the bioactives proposed for cosmetics and food applications, vitamins are the most frequently used. Despite the differences between the administration routes (oral for food and mainly dermal for cosmetics), some challenges are very similar (e.g., stability, bioactive load, average size, increase in drug bioaccessibility and bioavailability). In the present work, a systematic review of the technological advancements in the nanoencapsulation of vitamins using liposomes and related processes was performed; challenges and future perspectives were also discussed in order to underline the advantages of these drug-loaded biocompatible nanocarriers for cosmetics and food applications.

Encapsulation of Vitamins Using Nanoliposome: Recent Advances and Perspectives

Nowadays the importance of vitamins is clear for everyone. However, many patients are suffering from insufficient intake of vitamins. Incomplete intake of different vitamins from food sources due to their destruction during food processing or decrease in their bioavailability when mixing with other food materials, are factors resulting in vitamin deficiency in the body. Therefore, various lipid based nanocarriers such as nanoliposomes were developed to increase the bioavailability of bioactive compounds. Since the function of nanoliposomes containing vitamins on the body has a direct relationship with the quality of produced nanoliposomes, this review study was planned to investigate the several aspects of liposomal characteristics such as size, polydispersity index, zeta potential, and encapsulation efficiency on the quality of synthesized vitamin-loaded nanoliposomes.

Nano-vesicular carriers for bioactive compounds and their applications in food formulations

The most commonly used vesicular systems in the food industry include liposomes, niosomes, phytosomes, or transfersomes. This review focuses on showing how nano-vesicular carriers (NVCs) amend the properties of bioactive compounds (bioactives), making them suitable for food applications, especially functional foods. In this research, we elaborate on the question of whether bioactive-loaded NVCs affect various food aspects such as their antioxidant capacity, or sensory properties. This review also shows how NVCs improve the long-term release profile of bioactives during storage and at different pH values. Besides, the refinement of digestibility and bioaccessibility of diverse bioactives through NVCs in the gastrointestinal tract is elucidated. NVCs allow for stable vesicle formation (e.g. from anthocyanins) which reduces their cytotoxicity and proliferation of cancer cells, prolongs the release bioactives (e.g. d-limonene) with no critical burst, reduces the biofilm formation capacity of both Gram-positive/negative strains and their biofilm gene expression is down-regulated (in the case of tannic acid), low oxidation (e.g. iron) is endured when exposed to simulated gastric fluid, and unpleasant smell and taste are masked (in case of omega-3 fatty acids). After the incorporation of bioactive-loaded NVCs into food products, their antioxidant capacity is enhanced, maintaining high encapsulation efficiency and enduring pasteurization conditions, and they are not distinguished from control samples in sensory evaluation despite the reverse situation about free bioactives.

Liposomal β-Sitosterol Suppresses Metastasis of CT26/luc Colon Carcinoma via Inhibition of MMP-9 and Evoke of Immune System

β-sitosterol (SITO) has been reported with anticancer effects; however, with poor bioavailability. The current study aimed to investigate whether liposomal encapsulated β-sitosterol (LS) has a better inhibition effect on tumor metastasis than β-sitosterol in a CT26/luc lung metastasis mouse model and the possible underlying mechanism. LS was liposomal-encapsulated SITO and was delivered to mice by oral gavage. The cell viability was determined by the MTT assay, and invasiveness of the tumor cells and related protein expression were evaluated with the invasion assay and Western blotting. For therapeutic efficacy evaluation, male BALB/c mice were treated with PBS, SITO, and LS once a day for 7 days prior to intravenous injections of CT26/luc cells; treatments were continued twice a week post-cell inoculation throughout the entire experiment. Tumor growth inhibition was monitored by bioluminescent imaging (BLI). IL-12, IL-18, and IFN-γ in the intestinal epithelium were determined by ELISA. The results show that LS treatment had a better invasion inhibition with lower cytotoxicity than SITO when the same dose was utilized. Notably, mice treated with LS significantly exhibited fewer metastases to the lungs and other tissues/organs compared with the Control and SITO groups. Additionally, the IL-12, IL-18, and IFN-γ levels were significantly increased in the LS-treated mice compared with the Control and SITO groups. The underlying mechanism may be through the inhibition of MMP-9 and elicitation of the antitumoral Th1 immune response, such as increasing CD4⁺ and CD8⁺ T cells, IL-12, IL-18, and IFN-γ.

Mechanisms and Pharmaceutical Action of Lipid Nanoformulation of Natural Bioactive Compounds as Efficient Delivery Systems in the Therapy of Osteoarthritis

Osteoarthritis (OA) is a degenerative joint disease. An objective of the nanomedicine and drug delivery systems field is to design suitable pharmaceutical nanocarriers with controllable properties for drug delivery and site-specific targeting, in order to achieve greater efficacy and minimal toxicity, compared to the conventional drugs. The aim of this review is to present recent data on natural bioactive compounds with anti-inflammatory properties and efficacy in the treatment of OA, their formulation in lipid nanostructured carriers, mainly liposomes, as controlled release systems and the possibility to be intra-articularly (IA) administered. The literature regarding glycosaminoglycans, proteins, polyphenols and their ability to modify the cell response and mechanisms of action in different models of inflammation are reviewed. The advantages and limits of using lipid nanoformulations as drug delivery systems in OA treatment and the suitable route of administration are also discussed. Liposomes containing glycosaminoglycans presented good biocompatibility, lack of immune system activation, targeted delivery of bioactive compounds to the site of action, protection and efficiency of the encapsulated material, and prolonged duration of action, being highly recommended as controlled delivery systems in OA therapy through IA administration. Lipid nanoformulations of polyphenols were tested both in vivo and in vitro models that mimic OA conditions after IA or other routes of administration, recommending their clinical application.