Optimization and characterization of poly(lactic-co-glycolic acid) nanoparticles loaded with astaxanthin and evaluation of anti-photodamage effect in vitro

Deferasirox nanosuspension loaded dissolving microneedles for ocular drug delivery

Deferasirox (DFS) is an oral iron chelator that is employed in retinal ailments as a neuroprotectant against retinal injury and thus has utility in treating disorders such as excitoneurotoxicity and age-related macular degeneration (AMD). However, the conventional oral route of administration can present several disadvantages, e.g., the need for more frequent dosing and the first-pass effect. Microneedles (MNs) are minimally invasive systems that can be employed for intrascleral drug delivery without pain and can advantageously replace intravitreal injections therapy (IVT) as well as conventional oral routes of delivery for DFS. In this study, DFS was formulated into a nanosuspension (NS) through wet media milling employing PVA as a stabilizer, which was successfully loaded into polymeric dissolving MNs. DFS exhibited a 4-fold increase in solubility in DFS-NS compared to that of pure DFS. Moreover, the DFS-NSs exhibited excellent short-term stability and enhanced thermal stability, as confirmed through thermogravimetric analysis (TGA) studies. The mechanical characterization of the DFS-NS loaded ocular microneedles (DFS-NS-OcMNs), revealed that the system was sufficiently strong for effective scleral penetration. Optical coherence tomography (OCT) images confirmed the insertion of 81.23 ± 7.35 % of the total height of the MN arrays into full-thickness porcine sclera. Scleral deposition studies revealed 64 % drug deposition after just 5 min of insertion from DFS-NS-loaded ocular microneedles (OcMNs), which was almost 5 times greater than the deposition from pure DFS-OcMNs. Furthermore, both DFS and DFS-NS-OcMN exhibited remarkable cell viability when evaluated on human retinal pigment (ARPE) cells, suggesting their safety and appropriateness for use in the human eye. Therefore, loading DFS-NS into novel MN devices is a promising technique for effectively delivering DFS to the posterior segment of the eye in a minimally invasive manner.

Preparation and characterization of astaxanthin-loaded biodegradable polyhydroxybutyrate (PHB) microbeads for personal care and cosmetic applications

Due to its biodegradability and biocompatibility, polyhydroxybutyrate (PHB) has received attention as an alternative material for microbeads in personal care and cosmetic products (PCCPs). Here, PHB was produced from crude glycerol by an Escherichia coli JM109 strain harboring pUC19-23,119-phaCABA-04 without isopropyl β-D-1-thiogalactopyranoside (IPTG), an inducing agent. Astaxanthin-loaded PHB microbeads were prepared through emulsification-solvent evaporation. Studies were performed to determine how the concentration of PHB and stirring rate influence the size, surface morphology, encapsulation efficiency (EE), and astaxanthin release profile. The astaxanthin-loaded PHB microbeads exhibited a rough surface, 98.1 ± 0.7 % EE, spherical shape and 179 ± 44 μm size. In addition, <50 % astaxanthin release was observed within 240 min. Stability studies revealed that astaxanthin-loaded microbeads retained over 85.3 ± 4.2 % of astaxanthin after 90 days at 4 °C and showed a 2-fold reduction in astaxanthin degradation compared to their unencapsulated counterparts; thus, astaxanthin-loaded microbeads show promise for PCCPs applications. A cytotoxicity assay revealed that astaxanthin-loaded PHB microbeads were nontoxic to the human epidermal keratinocyte cell line, PSVK1, and EpiSkin® cells. Skin irritation and sensitization were not observed during a human repeated insult patch test (HRIPT), according to clinical practice guidelines of the Japanese dermatological association.

Microfluidic formulation of food additives-loaded nanoparticles for antioxidation

Browning has many important implications with nutrition and the shelf life of foods. Mitigating browning is of particular interest in food chemistry. The addition of antioxidants has been a common strategy to extend shelf life of drug and food products. In this work, we report a microfluidic technology for encapsulation of three common food additives (potassium metathionite (PMS), curcumin (CCM), and β-carotene (β-Car)) into nano-formulations using low-cost and readily available materials such as shellac. The food additives encapsulated nanoparticles provide a microenvironment that can prevent oxidation during daily storage. The results showed that the produced nanoparticles had a narrow size distribution with an average size of around 100 nm, were stable at conventional storage conditions (4 ºC) for 18 weeks, and had sustained release ability at 37 ºC, pH= 7.8, 160 rpm. In addition, further experiments showed that the formulation of hydrophobic additives, such as CCM and β-Car did not only improve their bioavailability but also allowed for the encapsulation of a combination of ingredients. In addition, the antioxidants loaded nanoparticles demonstrated good biocompatibility, low toxicity to human cells. The longer release time of encapsulated food additives increases shelf life of foods and enhances consumer purchase preferences, which not only saves costs but also reduces waste. In summary, this study shows that such antioxidant-loaded nanoparticles provide a promising strategy in extending the shelf life of food products.

Astaxanthin nanoparticles ameliorate dextran sulfate sodium-induced colitis by alleviating oxidative stress, regulating intestinal flora, and protecting the intestinal barrier

This study aimed to develop a novel astaxanthin nanoparticle using gum arabic (GA) and whey protein powder enriched with milk fat globule membranes (MFGM-WPI) as carriers and to investigate its effect and alleviation mechanism on colitis in mice. We demonstrated that MFGM-GA-astaxanthin could improve the bioaccessibility of astaxanthin and cope with oxidative stress more effectively in a Caco-2 cell model. In vivo studies demonstrated that MFGM-GA-astaxanthin alleviated colitis symptoms and repaired intestinal barrier function by increasing the expression of mucin 2, occludin, and zonula occludens-1. This was attributed to the alleviating effect of MFGM-GA-astaxanthin on oxidative stress. Moreover, MFGM-GA-astaxanthin restored the abnormalities of flora caused by dextran sulfate sodium, including Lactobacillus, Bacteroides, Ruminococcus, and Shigella. This study provides a basis for the therapeutic effect of astaxanthin nanoparticles on colon diseases.

Supersaturable Solid Self-microemulsifying Delivery Systems of Astaxanthin via Spray Drying: Effects of Polymers and Solid Carriers

This study aimed to develop the solid astaxanthin-encapsulated self-microemulsifying delivery system (S-AST SMEDS) spray-dried particles and investigate the effect of materials in formulations on product characteristics. The optimized liquid AST SMEDS incorporated with a polymeric precipitation inhibitor (PI) was solidified with a solid carrier by spray drying. Physicochemical properties of S-AST SMEDS spray-dried powders including morphology, particle size and distribution, flowability, solid-state characters, moisture content, yield, loading capacity of AST, and reconstitution properties were examined. Polymeric PIs seemed to have an impact on particles' size, surface smoothness, and flowability while solid carriers had an effect on the particles' moisture content and droplet size of microemulsions obtained after reconstitution. The amount of AST encapsulated in S-SMEDS powder was influenced by both polymer and solid carriers. Dissolution and short-term stability of S-AST SMEDS were also studied. Our developed spray-dried solid SMEDS particles helped enhance AST dissolution rate.

Microfluidic fabrication of size-controlled nanocarriers with improved stability and biocompatibility for astaxanthin delivery

Improving the stability of astaxanthin (AST) is a vital way to enhance its oral bioavailability. In this study, a microfluidic strategy for the preparation of astaxanthin nano-encapsulation system was proposed. Thanks to the precise control of microfluidic and the rapid preparation ability of the Mannich reaction, the resulting astaxanthin nano-encapsulation system (AST-ACNs-NPs) was obtained with average sizes of 200 nm, uniform spherical shape and high encapsulation rate of 75%. AST was successfully doped into the nanocarriers, according to the findings of the DFT calculation, fluorescence spectrum, Fourier transform spectroscopy, and UV-vis absorption spectroscopy. Compared with free AST, AST-ACNs-NPs showed better stability under the conditions of high temperature, pH and UV light with<20% activity loss rate. The nano-encapsulation system containing AST could significantly reduce the hydrogen peroxide produced by reactive oxygen species, keep the potential of the mitochondrial membrane at a healthy level, and improve the antioxidant ability of H₂O₂-induced RAW 264.7 cells. These results indicated that microfluidics-based astaxanthin delivery system is an effective solution to improve the bioaccessibility of bioactive substances and has potential application value in food industry.

Production and therapeutic use of astaxanthin in the nanotechnology era

Astaxanthin (AXT) is a red fat-soluble pigment found naturally in aquatic animals, plants, and various microorganisms and can be manufactured artificially using chemical catalysis. AXT is a xanthophyll carotenoid with a high potential for scavenging free radicals. Several studies have investigated AXT efficacy against diseases such as neurodegenerative, ocular, skin, and cardiovascular hypertension, diabetes, gastrointestinal and liver diseases, and immuno-protective functions. However, its poor solubility, low stability to light and oxygen, and limited bioavailability are major obstacles hindering its wide applications as a therapeutic agent or nutritional supplement. Incorporating AXT with nanocarriers holds great promise in enhancing its physiochemical properties. Nanocarriers are delivery systems with several benefits, including surface modification, bioactivity, and targeted medication delivery and release. Many approaches have been applied to enhance AXT's medicinal effect, including solid lipid nanoparticles, nanostructured lipid carriers (NLCs) and polymeric nanospheres. AXT nano-formulations have demonstrated a high antioxidant and anti-inflammatory effect, significantly affecting cancer in different organs. This review summarizes the most recent data on AXT production, characterization, biological activity, and therapeutic usage, focusing on its uses in the nanotechnology era.

Design of Chitosan-Coated, Quercetin-Loaded PLGA Nanoparticles for Enhanced PSMA-Specific Activity on LnCap Prostate Cancer Cells

Nanoparticles are designed to entrap drugs at a high concentration, escape clearance by the immune system, be selectively taken up by cancer cells, and release bioactives in a rate-modulated manner. In this study, quercetin-loaded PLGA nanoparticles were prepared and optimized to determine whether coating with chitosan would increase the cellular uptake of the nanoparticles and if the targeting ability of folic acid as a ligand can provide selective toxicity and enhanced uptake in model LnCap prostate cancer cells, which express high levels of the receptor prostate-specific membrane antigen (PSMA), compared to PC-3 cells, that have relatively low PSMA expression. A design of experiments approach was used to optimize the PLGA nanoparticles to have the maximum quercetin loading, optimal cationic charge, and folic acid coating. We examined the in vitro release of quercetin and comparative cytotoxicity and cellular uptake of the optimized PLGA nanoparticles and revealed that the targeted nano-system provided sustained, pH-dependent quercetin release, and higher cytotoxicity and cellular uptake, compared to the non-targeted nano-system on LnCap cells. There was no significant difference in the cytotoxicity or cellular uptake between the targeted and non-targeted nano-systems on PC-3 cells (featured by low levels of PSMA), pointing to a PSMA-specific mechanism of action of the targeted nano-system. The findings suggest that the nano-system can be used as an efficient nanocarrier for the targeted delivery and release of quercetin (and other similar chemotherapeutics) against prostate cancer cells.

Research progress of Astaxanthin nano-based drug delivery system: Applications, prospects and challenges?

Astaxanthin (ASX) is a kind of carotenoid widely distributed in nature, which has been shown to extremely strong antioxidative effects and significant preventive and therapeutic effects on cancer, diabetes, cardiovascular disease, etc. However, its application in the medical field is greatly limited due to its poor water solubility, unstable chemical properties and other shortcomings. In recent years, the nano-based drug delivery systems such as nanoparticles, liposomes, nanoemulsions, nanodispersions, and polymer micelles, have been used as Astaxanthin delivery carriers with great potential for clinical applications, which have been proved that they can enhance the stability and efficacy of Astaxanthin and achieve targeted delivery of Astaxanthin. Herein, based on the pharmacological effects of Astaxanthin, we reviewed the characteristics of various drug delivery carriers, which is of great significance for improving the bioavailability of Astaxanthin.

Improving the biological activities of astaxanthin using targeted delivery systems

The antioxidant and anti-inflammatory properties of astaxanthin (AST) enable it to protect against oxidative stress-related and inflammatory diseases with a range of biological effects. These activities provide the potential to develop healthier food products. Therefore, it would be beneficial to design delivery systems for AST to overcome its low stability, control its release, and/or improve its bioavailability. This review discusses the basis for AST's various biological activities and the factors limiting these activities, including stability, solubility, and bioavailability. It also discusses the different systems available for the targeted delivery of AST and their applications in enhancing the biological activity of AST. These include systems that are candidates for preventive and therapeutic effects, which include nerves, liver, and skin, particularly for possible cancer reduction. Targeted delivery of AST to specific regions of the gastrointestinal tract, or more selectively to target tissues and cells, can be achieved using targeted delivery systems to increase the biological activities of AST.

Formulation Approaches to Crystalline Status Modification for Carotenoids: Impacts on Dissolution, Stability, Bioavailability, and Bioactivities

Carotenoids, including carotenes and xanthophylls, have been identified as bioactive ingredients in foods and are considered to possess health-promoting effects. From a biopharmaceutical perspective, several physicochemical characteristics, such as scanty water solubility, restricted dissolution, and susceptibility to oxidation may influence their oral bioavailability and eventually, their effectiveness. In this review, we have summarized various formulation approaches that deal with the modification of crystalline status for carotenoids, which may improve their physicochemical properties, oral absorption, and biological effects. The mechanisms involving crystalline alteration and the typical methods for examining crystalline states in the pharmaceutical field have been included, and representative formulation approaches are introduced to unriddle the mechanisms and effects more clearly.

Glycyrrhizic acid Poly(D,L-lactide-co-glycolide) nanoparticles: anti-aging cosmeceutical formulation for topical applications

Glycyrrhizic acid (GA) is one of the components of licorice roots (Glycyrrhiza glabra L.). GA is a triterpenoid saponin can be used as a medicinal plant with its antiallergic, antiviral, anti-inflammatory, anti-ulcer, hepatoprotective, anticancer, anti-oxidation activities and several other therapeutic properties. The aim of this study is to develop an anti-aging formulation for topical application containing GA. In this context, GA-loaded Poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles (NPs) were prepared using the double emulsion method, and were characterized by various spectroscopic methods. The efficacy of GA-PLGA NPs was evaluated with in vitro and in silico methods. The encapsulation efficiency and loading capacity were calculated. The in vitro release study was conducted, and the GA release profile was determined. The genotoxic activity of GA and GA-PLGA NPs was evaluated by the Ames test using TA98 and TA100 mutant strains of Salmonella typhimurium. The cytotoxic potential of GA-PLGA NPs was evaluated on the HaCaT cell line using the MTT assay. According to the genotoxicity and cytotoxicity results, it was found that the GA-PLGA NP formulation did not exhibit genotoxic and cytotoxic effects. Moreover, the efficacy of GA in preventing UVB-induced photo-aging in HaCaT cells and the clarification of the molecular mechanism of GA binding to MMPs were revealed by molecular docking analysis. In addition, through molecular dynamics (MD) analysis, the binding interaction of GA with MMPs in a dynamic system, and protein-ligand stability were predicted as a result of 50 ns MD simulation studies considering various analysis parameters. Finally, it was evaluated that GA-PLGA nanoformulation might be used as an alternative anti-aging skin care product candidate via topical application.

Microfluidic-Based Formulation of Essential Oils-Loaded Chitosan Coated PLGA Particles Enhances Their Bioavailability and Nematocidal Activity

In this study, poly (lactic-co-glycolic) acid (PLGA) particles were synthesized and coated with chitosan. Three essential oil (EO) components (eugenol, linalool, and geraniol) were entrapped inside these PLGA particles by using the continuous flow-focusing microfluidic method and a partially water-miscible solvent mixture (dichloromethane: acetone mixture (1:10)). Encapsulation of EO components in PLGA particles was confirmed by Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction, with encapsulation efficiencies 95.14%, 79.68%, and 71.34% and loading capacities 8.88%, 8.38%, and 5.65% in particles entrapped with eugenol, linalool, and geraniol, respectively. The EO components’ dissociation from the loaded particles exhibited an initial burst release in the first 8 h followed by a sustained release phase at significantly slower rates from the coated particles, extending beyond 5 days. The EO components encapsulated in chitosan coated particles up to 5 μg/mL were not cytotoxic to bovine gut cell line (FFKD-1-R) and had no adverse effect on cell growth and membrane integrity compared with free EO components or uncoated particles. Chitosan coated PLGA particles loaded with combined EO components (10 µg/mL) significantly inhibited the motility of the larval stage of Haemonchus contortus and Trichostrongylus axei by 76.9%, and completely inhibited the motility of adult worms (p < 0.05). This nematocidal effect was accompanied by considerable cuticular damage in the treated worms, reflecting a synergistic effect of the combined EO components and an additive effect of chitosan. These results show that encapsulation of EO components, with a potent anthelmintic activity, in chitosan coated PLGA particles improve the bioavailability and efficacy of EO components against ovine gastrointestinal nematodes.

Production, physicochemical investigations, antioxidant effect, and cellular uptake in Caco-2 cells of the supersaturable astaxanthin self-microemulsifying tablets

The purpose of this study was to develop astaxanthin (AST)-loaded self-microemulsifying drug delivery system (SMEDDS) tablets and evaluate their physicochemical and biological properties. The optimized liquid (L)-AST SMEDDS formulation was composed of rice bran oil (33.67%), Kolliphor® RH 40 (34.70%), and Span® 20 (31.63%). Two types of hydrophilic polymers (hydroxypropyl methylcellulose, HPMC, and polyvinyl alcohol, PVA) solutions were selected as a precipitation inhibitor for AST and incorporated into L-AST SMEDDS to obtain supersaturation and enhance dissolution of AST. The formulation was then mixed with microcrystalline cellulose and subsequently transformed to solid S-AST SMEDDS particles using a spray dryer prior to direct compression into tablets. The HPMC AST SMEDDS tablet and PVA AST SMEDDS tablet were characterized for their physicochemical properties, dissolution, AST release, and stabilities. Moreover, the cellular uptake and antioxidant effect of AST SMEDDS tablets were evaluated in Caco-2 cells. With good tablet characters, both HPMC AST SMEDDS tablet and PVA AST SMEDDS tablet dissolution profiles were improved compared to that of raw AST. While initially less than 50% of AST released from HPMC AST SMEDDS tablet and PVA AST SMEDDS tablet in pH 1.2 medium, after 6 h more than 98% of AST releases in pH 6.8 were achieved which was similar to L-AST SMEDDS profile. Cellular antioxidant activities of L-AST SMEDDS and HPMC AST SMEDDS tablet & PVA AST SMEDDS tablet were significantly greater than pure AST powder. HPMC AST SMEDDS tablet showed better uptake and deeper penetration through Caco-2 cells than that in PVA AST SMEDDS tablet and pure powder. Our successfully developed AST SMEDDS tablets were demonstrated to be a potential platform to deliver highly lipophilic AST and improve permeation and bioavailability.

The Encapsulation of Citicoline within Solid Lipid Nanoparticles Enhances Its Capability to Counteract the 6-Hydroxydopamine-Induced Cytotoxicity in Human Neuroblastoma SH-SY5Y Cells

(1) Backgrond: Considering the positive effects of citicoline (CIT) in the management of some neurodegenerative diseases, the aim of this work was to develop CIT-Loaded Solid Lipid Nanoparticles (CIT-SLNs) for enhancing the therapeutic use of CIT in parkinsonian syndrome; (2) Methods: CIT-SLNs were prepared by the melt homogenization method using the self-emulsifying lipid Gelucire® 50/13 as lipid matrix. Solid-state features on CIT-SLNs were obtained with FT-IR, thermal analysis (DSC) and X-ray powder diffraction (XRPD) studies. (3) Results: CIT-SLNs showed a mean diameter of 201 nm, −2.20 mV as zeta potential and a high percentage of entrapped CIT. DSC and XRPD analyses evidenced a greater amorphous state of CIT in CIT-SLNs. On confocal microscopy, fluorescent SLNs replacing unlabeled CIT-SLNs released the dye selectively in the cytoplasm. Biological evaluation showed that pre-treatment of SH-SY5Y dopaminergic cells with CIT-SLNs (50 µM) before the addition of 40 µM 6-hydroxydopamine (6-OHDA) to mimic Parkinson’s disease’s degenerative pathways counteracts the cytotoxic effects induced by the neurotoxin, increasing cell viability with the consistent maintenance of both nuclear and cell morphology. In contrast, pre-treatment with CIT 50 and 60 µM or plain SLNs for 2 h followed by 6-OHDA (40 µM) did not significantly influence cell viability. (4) Conclusions: These data suggest an enhanced protection exerted by CIT-SLNs with respect to free CIT and prompt further investigation of possible molecular mechanisms that underlie this difference.

Nanocarrier System: State-of-the-Art in Oral Delivery of Astaxanthin

Astaxanthin (3,3′-dihydroxy-4,4′-diketo-β-β carotene), which belongs to the xanthophyll class, has shown potential biological activity in in vitro and in vivo models including as a potent antioxidant, anti-lipid peroxidation and cardiovascular disease prevention agent. It is mainly extracted from an alga, Haematococcus pluvialis. As a highly lipid-soluble carotenoid, astaxanthin has been shown to have poor oral bioavailability, which limits its clinical applications. Recently, there have been several suggestions and the development of various types of nano-formulation, loaded with astaxanthin to enhance their bioavailability. The employment of nanoemulsions, liposomes, solid lipid nanoparticles, chitosan-based and PLGA-based nanoparticles as delivery vehicles of astaxanthin for nutritional supplementation purposes has proven a higher oral bioavailability of astaxanthin. In this review, we highlight the pharmacological properties, pharmacokinetics profiles and current developments of the nano-formulations of astaxanthin for its oral delivery that are believed to be beneficial for future applications. The limitations and future recommendations are also discussed in this review.

Preparation, Characterization, and In Vitro Anticancer Activity Evaluation of Broccoli-Derived Extracellular Vesicle-Coated Astaxanthin Nanoparticles

Astaxanthin (AST) is a type of ketone carotenoid having significant antioxidation and anticancer abilities. However, its application is limited due to its low stability and bioavailability. In our study, poly (lactic-co-glycolic acid) (PLGA)-encapsulated AST (AST@PLGA) nanoparticles were prepared by emulsion solvent evaporation method and then further processed by ultrasound with broccoli-derived extracellular vesicles (BEVs), thereby evolving as BEV-coated AST@PLGA nanoparticles (AST@PLGA@BEVs). The preparation process and methods were optimized by three factors and three levels of response surface method to increase drug loading (DL). After optimization, the DL was increased to 6.824%, and the size, polydispersity index, and zeta potential of AST@PLGA@BEVs reached 191.60 ± 2.23 nm, 0.166, and -15.85 ± 0.92 mV, respectively. Moreover, AST@PLGA@BEVs exhibited more notable anticancer activity than AST in vitro. Collectively, these results indicate that the method of loading AST in broccoli-derived EVs is feasible and has important significance for the further development and utilization of AST as a functional food.

Emerging trends of nanotechnology in advanced cosmetics

The cosmetic industry is dynamic and ever-evolving. Especially with the introduction and incorporation of nanotechnology-based approaches into cosmetics for evincing novel formulations that confers aesthetic as well as therapeutic benefits. Nanocosmetics acts via numerous delivery mechanisms which involves lipid nanocarrier systems, polymeric or metallic nanoparticles, nanocapsules, dendrimers, nanosponges,etc. Each of these, have particular characteristic properties, which facilitates increased drug loading, enhanced absorption, better cosmetic efficacy, and many more. This article discusses the different classes of nanotechnology-based cosmetics and the nanomaterials used for their formulation, followed by outlining the categories of nanocosmetics and the scope of their utility pertaining to skin, hair, nail, lip, and/or dental care and protection thereof. This review also highlights and discusses about the key drivers of the cosmetic industry and the impending need of corroborating a healthy regulatory framework, refocusing attention towards consumer needs and trends, inculcating sustainable techniques and tenets of green ecological principles, and lastly making strides in nano-technological advancements which will further propel the growth of the cosmetic industry.

Contribution of Nanoscience Research in Antioxidants Delivery Used in Nutricosmetic Sector

Nanoscience applications in the food and cosmetic industry offer many potential benefits for consumers and society. Nanotechnologies permit the manipulation of matter at the nanoscale level, resulting in new properties and characteristics useful in food and cosmetic production, processing, packaging, and storage. Nanotechnology protects sensitive bioactive compounds, improves their bioavailability and water solubility, guarantees their release at a site of action, avoids contact with other constituents, and masks unpleasant taste. Biopolymeric nanoparticles, nanofibers, nanoemulsions, nanocapsules, and colloids are delivery systems used to produce food supplements and cosmetics. There are no barriers to nanoscience applications in food supplements and cosmetic industries, although the toxicity of nano-sized delivery systems is not clear. The physicochemical and toxicological characterization of nanoscale delivery systems used by the nutricosmeceutic industry is reviewed in this work.

Astaxanthin accumulation in Microcystis aeruginosa under different light quality

The aim of this work was to uncover the astaxanthin biosynthesis mechanism in Microcystis aeruginosa under optimum light quality, and promote astaxanthin production using this alga. Among purple, blue and red light, only purple light promoted M. aeruginosa cell growth compared with white light, due to up-regulating expression of the genes related with DNA replication. An increase was detected in the photosynthetic rate under purple light, which should be caused by the raised carotenoid content and up-regulation of the genes associated with light reaction and carbon fixation. Compared with white light, purple light increased the levels of β-carotene, zeaxanthin and astaxanthin by up-regulating expression of the genes related with methylerythritol-4-phosphate pathway (MEP) and astaxanthin biosynthesis. For red and blue light, they did not impact or declined the content of astaxanthin and its precursors. Therefore, purple light promoted M. aeruginosa cell growth and astaxanthin production by up-regulating related gene expression.

"Light modulates transcriptomic dynamics upregulating astaxanthin accumulation in Haematococcus: A review"

Haematococcus pluvialis is a green alga that can accumulate high astaxanthin content, a commercially demanding market keto food. Due to its high predicted market value of about 3.4 billion USD in 2027, it is essential to increase its production. Therefore, it is crucial to understand the genetic mechanism and gene expressions profile during astaxanthin synthesis. The effect of poly- and mono-chromatic light of different wavelengths and different intensities have shown to influence the gene expression towards astaxanthin production. This includes transcriptomic gene analysis in H. pluvialis underneath different levels of illumination stress. This review has placed the most recent data on the effects of light on bioastaxanthin production in the context of previous studies, which were more focused on the biochemical and physiological sides. Doing so, it contributes to delineate new ways along the biotechnological process with the aim to increase bioastaxanthin production while decreasing production costs.

Chitosan-Coated PLGA Nanoparticles Encapsulating Triamcinolone Acetonide as a Potential Candidate for Sustained Ocular Drug Delivery

The current treatment for the acquired retinal vasculopathies involves lifelong repeated intravitreal injections of either anti-vascular endothelial growth factor (VEGF) therapy or modulation of inflammation with steroids. Consequently, any treatment modification that decreases this treatment burden for patients and doctors alike would be a welcome intervention. To that end, this research aims to develop a topically applied nanoparticulate system encapsulating a corticosteroid for extended drug release. Poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) supports the controlled release of the encapsulated drug, while surface modification of these NPs with chitosan might prolong the mucoadhesion ability leading to improved bioavailability of the drug. Triamcinolone acetonide (TA)-loaded chitosan-coated PLGA NPs were fabricated using the oil-in-water emulsion technique. The optimized surface-modified NPs obtained using Box-Behnken response surface statistical design were reproducible with a particle diameter of 334 ± 67.95 to 386 ± 15.14 nm and PDI between 0.09 and 0.15. These NPs encapsulated 55-57% of TA and displayed a controlled release of the drug reaching a plateau in 27 h. Fourier-transform infrared spectroscopic (FTIR) analysis demonstrated characteristic peaks for chitosan (C-H, CONH2 and C-O at 2935, 1631 and 1087 cm-1, respectively) in chitosan-coated PLGA NPs. This result data, coupled with positive zeta potential values (ranged between +26 and +33 mV), suggests the successful coating of chitosan onto PLGA NPs. Upon coating of the NPs, the thermal stability of the drug, polymer, surfactant and PLGA NPs have been enhanced. The characteristics of the surface-modified NPs supports their use as potential candidates for topical ocular drug delivery for acquired retinal vasculopathies.

Astaxanthin Delivery Systems for Skin Application: A Review

Astaxanthin (AST) is a biomolecule known for its powerful antioxidant effect, which is considered of great importance in biochemical research and has great potential for application in cosmetics, as well as food products that are beneficial to human health and medicines. Unfortunately, its poor solubility in water, chemical instability, and low oral bioavailability make its applications in the cosmetic and pharmaceutical field a major challenge for the development of new products. To favor the search for alternatives to enhance and make possible the use of AST in formulations, this article aimed to review the scientific data on its application in delivery systems. The search was made in databases without time restriction, using keywords such as astaxanthin, delivery systems, skin, cosmetic, topical, and dermal. All delivery systems found, such as liposomes, particulate systems, inclusion complexes, emulsions, and films, presented peculiar advantages able to enhance AST properties, among which are stability, antioxidant potential, biological activities, and drug release. This survey showed that further studies are needed for the industrial development of new AST-containing cosmetics and topical formulations.

Microalgae Encapsulation Systems for Food, Pharmaceutical and Cosmetics Applications

Microalgae are microorganisms with a singular biochemical composition, including several biologically active compounds with proven pharmacological activities, such as anticancer, antioxidant and anti-inflammatory activities, among others. These properties make microalgae an interesting natural resource to be used as a functional ingredient, as well as in the prevention and treatment of diseases, or cosmetic formulations. Nevertheless, natural bioactives often possess inherent chemical instability and/or poor solubility, which are usually associated with low bioavailability. As such, their industrial potential as a health-promoting substance might be severely compromised. In this context, encapsulation systems are considered as a promising and emerging strategy to overcome these shortcomings due to the presence of a surrounding protective layer. Diverse systems have already been reported in the literature for natural bioactives, where some of them have been successfully applied to microalgae compounds. Therefore, this review focuses on exploring encapsulation systems for microalgae biomass, their extracts, or purified bioactives for food, pharmaceutical, and cosmetic purposes. Moreover, this work also covers the most common encapsulation techniques and types of coating materials used, along with the main findings regarding the beneficial effects of these systems.

On a Beam of Light: Photoprotective Activities of the Marine Carotenoids Astaxanthin and Fucoxanthin in Suppression of Inflammation and Cancer

Every day, we come into contact with ultraviolet radiation (UVR). If under medical supervision, small amounts of UVR could be beneficial, the detrimental and hazardous effects of UVR exposure dictate an unbalance towards the risks on the risk-benefit ratio. Acute and chronic effects of ultraviolet-A and ultraviolet-B involve mainly the skin, the immune system, and the eyes. Photodamage is an umbrella term that includes general phototoxicity, photoaging, and cancer caused by UVR. All these phenomena are mediated by direct or indirect oxidative stress and inflammation and are strictly connected one to the other. Astaxanthin (ASX) and fucoxanthin (FX) are peculiar marine carotenoids characterized by outstanding antioxidant properties. In particular, ASX showed exceptional efficacy in counteracting all categories of photodamages, in vitro and in vivo, thanks to both antioxidant potential and activation of alternative pathways. Less evidence has been produced about FX, but it still represents an interesting promise to prevent the detrimental effect of UVR. Altogether, these results highlight the importance of digging into the marine ecosystem to look for new compounds that could be beneficial for human health and confirm that the marine environment is as much as full of active compounds as the terrestrial one, it just needs to be more explored.

Nanomaterials for Skin Delivery of Cosmeceuticals and Pharmaceuticals

Skin aging is described as dermatologic changes either naturally occurring over the course of years or as the result of the exposure to environmental factors (e.g., chemical products, pollution, infrared and ultraviolet radiations). The production of collagen and elastin, the main structural proteins responsible for skin strength and elasticity, is reduced during aging, while their role in skin rejuvenation can trigger a wrinkle reversing effect. Elasticity loss, wrinkles, dry skin, and thinning are some of the signs that can be associated with skin aging. To overcome skin aging, many strategies using natural and synthetic ingredients are being developed aiming to reduce the signs of aging and/or to treat age-related skin problems (e.g., spots, hyper- or hypopigmentation). Among the different approaches in tissue regeneration, the use of nanomaterials loaded with cosmeceuticals (e.g., phytochemicals, vitamins, hyaluronic acid, and growth factors) has become an interesting alternative. Based on their bioactivities and using different nanoformulations as efficient delivery systems, several cosmeceutical and pharmaceutical products are now available on the market aiming to mitigate the signs of aged skin. This manuscript discusses the state of the art of nanomaterials commonly used for topical administration of active ingredients formulated in nanopharmaceuticals and nanocosmeceuticals for skin anti-aging.

The Astaxanthin Aggregation Pattern Greatly Influences Its Antioxidant Activity: A Comparative Study in Caco-2 Cells

Astaxanthin is an excellent antioxidant that can form unstable aggregates in biological or artificial systems. The changes of astaxanthin properties caused by molecular aggregation have gained much attention recently. Here, water-dispersible astaxanthin H- and J-aggregates were fabricated and stabilized by a natural DNA/chitosan nanocomplex (respectively noted as H-ADC and J-ADC), as evidenced by ultraviolet and visible spectrophotometry, Fourier transform infrared spectroscopy, and Raman spectroscopy. Compared with J-ADC, H-ADC with equivalent astaxanthin loading capacity and encapsulation efficiency showed smaller particle size and similar zeta potential. To explore the antioxidant differences between astaxanthin H- and J-aggregates, H-ADC and J-ADC were subjected to H₂O₂-pretreated Caco-2 cells. Compared with astaxanthin monomers and J-aggregates, H-aggregates showed a better cytoprotective effect by promoting scavenging of intracellular reactive oxygen species. Furthermore, in vitro 1,1-diphenyl-2-picrylhydrazyl and hydroxyl free radical scavenging studies confirmed a higher efficiency of H-aggregates than J-aggregates or astaxanthin monomers. These findings give inspiration to the precise design of carotenoid aggregates for efficient utilization.