Functionalized chitosan nanoparticles for cutaneous delivery of a skin whitening agent: an approach to clinically augment the therapeutic efficacy for melasma treatment

Progress in Topical and Transdermal Drug Delivery Research-Focus on Nanoformulations

Skin is the largest organ and a multifunctional interface between the body and its environment. It acts as a barrier against cold, heat, injuries, infections, chemicals, radiations or other exogeneous factors, and it is also known as the mirror of the soul. The skin is involved in body temperature regulation by the storage of fat and water. It is an interesting tissue in regard to the local and transdermal application of active ingredients for prevention or treatment of pathological conditions. Topical and transdermal delivery is an emerging route of drug and cosmetic administration. It is beneficial for avoiding side effects and rapid metabolism. Many pharmaceutical, technological and cosmetic innovations have been described and patented recently in the field. In this review, the main features of skin morphology and physiology are presented and are being followed by the description of classical and novel nanoparticulate dermal and transdermal drug formulations. The biophysical aspects of the penetration of drugs and cosmetics into or across the dermal barrier and their investigation in diffusion chambers, skin-on-a-chip devices, high-throughput measuring systems or with advanced analytical techniques are also shown. The current knowledge about mathematical modeling of skin penetration and the future perspectives are briefly discussed in the end, all also involving nanoparticulated systems.

Developing Plant Exosomes as an Advanced Delivery System for Cosmetic Peptide

Peptides are a promising skincare ingredient, but due to their inherent instability and the barrier function of the skin's surface, they often have limited skin absorption and penetration, which can significantly hinder their skincare benefits. To address this, a novel technique called NanoGlow has been introduced for encapsulating peptide-based cosmetic raw materials into engineered nanosized plant-derived exosomes (pExo) to achieve the goal of a healthier and more radiant skin state. In this approach, pExo served as carriers for cosmetic peptides across the intact skin barrier, enhancing their biological effectiveness in skin beauty. The NanoGlow strategy combines chemical activation and physical proencapsulation, boasting a high success rate and straightforward and stable operation, making it suitable for large-scale production. Comprehensive analysis using in vitro cellular absorption and skin penetration models has demonstrated that the nanosized pExo carriers significantly improve peptide penetration into the skin compared to free peptides. Furthermore, in vivo tissue slice studies have shown that pExo carriers efficiently deliver acetyl hexapeptide-8 to the skin's dermis, surpassing the performance of free peptides. Cosmetic skincare effect analysis has also indicated that pExo-loaded cosmetic peptides deliver superior results. Therefore, the NanoGlow technique harnesses the natural size and properties of pExo to maximize the bioavailability of cosmetic peptides, holding great promise for developing advanced peptide delivery systems in both the cosmetic and medical drug industries.

Different therapeutic approaches in melasma: advances and limitations

Melasma is a chronic hyperpigmentation skin disorder that is more common in the female gender. Although melasma is a multifactorial skin disorder, however, sun-exposure and genetic predisposition are considered as the main etiologic factors in melasma occurrence. Although numerous topical and systemic therapeutic agents and also non-pharmacologic procedural treatments have been considered in melasma management, however, the commonly available therapeutic options have several limitations including the lack of sufficient clinical effectiveness, risk of relapse, and high rate of unwanted adverse drug reactions. Recruitment of nanotechnology for topical drug delivery in melasma management can lead to enhanced skin penetration, targeted drug delivery to the site of action, longer deposition at the targeted area, and limit systemic absorption and therefore systemic availability and adverse drug reactions. In the current review, first of all, the etiology, pathophysiology, and severity classification of melasma have been considered. Then, various pharmacologic and procedural therapeutic options in melasma treatment have been discussed. Afterward, the usage of various types of nanoparticles for the purpose of topical drug delivery for melasma management was considered. In the end, numerous clinical studies and controlled clinical trials on the assessment of the effectiveness of these novel topical formulations in melasma management are summarized.

Recent progress on polySarcosine as an alternative to PEGylation: Synthesis and biomedical applications

Biotherapeutic PEGylation to prolong action of medications has gained popularity over the last decades. Various hydrophilic natural polymers have been developed to tackle the drawbacks of PEGylation, such as its accelerated blood clearance and non-biodegradability. Polypeptoides, such as polysarcosine (pSar), have been explored as hydrophilic substitutes for PEG. pSar has PEG-like physicochemical characteristics such as water solubility and no reported cytotoxicity and immunogenicity. This review discusses pSar derivatives, synthesis, characterization approaches, biomedical applications, in addition to the challenges and future perspectives of pSar based biomaterials as an alternative to PEG.

Synergistic anticancer effect of Pistacia lentiscus essential oils and 5-Fluorouracil co-loaded onto biodegradable nanofibers against melanoma and breast cancer

Chemoresistance and severe toxicities represent major drawbacks of chemotherapy. Natural extracts, including the essential oils of Pistacia lentiscus (PLEO), exhibit substantial anticancer and anti-inflammatory activities where different cancers are reported to dramatically recess following targeting with PLEO. PLEO has promising antimicrobial, anticancer, and anti-inflammatory properties. However, the therapeutic properties of PLEO are restricted by limited stability, bioavailability, and targeting ability. PLEO nanoformulation can maximize their physicochemical and therapeutic properties, overcoming their shortcomings. Hence, PLEO was extracted and its chemical composition was determined by GC-MS. PLEO and 5-Fluorouracil (5FU) were electrospun into poly-ε-caprolactone nanofibers (PCL-NFs), of 290.71 nm to 680.95 nm diameter, to investigate their anticancer and potential synergistic activities against triple-negative breast cancer cells (MDA-MB-231), human adenocarcinoma breast cancer cells (MCF-7), and human skin melanoma cell line (A375). The prepared nanofibers (NFs) showed enhanced thermal stability and remarkable physical integrity and tensile strength. Biodegradability studies showed prolonged stability over 42 days, supporting the NFs use as a localized therapy of breast tissues (postmastectomy) or melanoma. Release studies revealed sustainable release behaviors over 168 h, with higher released amounts of 5FU and PLEO at pH 5.4, indicating higher targeting abilities towards cancer tissues. NFs loaded with PLEO showed strong antioxidant properties. Finally, NFs loaded with either PLEO or 5FU depicted greater anticancer activities compared to free compounds. The highest anticancer activities were observed with NFs co-loaded with PLEO and 5FU. The developed 5FU-PLEO-PCL-NFs hold potential as a local treatment of breast cancer tissues (post-mastectomy) and melanoma to minimize their  possible recurrence.

Injectable systems of chitosan in situ forming composite gel incorporating linezolid-loaded biodegradable nanoparticles for long-term treatment of bone infections

The objective of the current study was to create an efficient, minimally invasive combined system comprising in situ forming hydrogel loaded with both spray-dried polymeric nanoparticles encapsulating linezolid and nanohydroxyapatite for local injection to bones or their close vicinity. The developed system was designed for a dual function namely releasing the drug in a sustained manner for long-term treatment of bone infections and supporting bone proliferation and new tissues generation. To achieve these objectives, two release sustainment systems for linezolid were optimized namely a composite in situ forming chitosan hydrogel and spray-dried PLGA/PLA solid nanoparticles. The composite, in situ forming hydrogel of chitosan was prepared using two different gelling agents namely glycerophosphate (GP) and sodium bicarbonate (NaHCO3) at 3 different concentrations each. The spray-dried linezolid-loaded PLGA/PLA nanoparticles were developed using a water-soluble carrier (PVP K30) and a lipid soluble one (cetyl alcohol) along with 3 types of DL-lactide and/or DL-lactide-co-glycolide copolymer using nano-spray-drying technique. Finally, the optimized spray-dried linezolid nanoparticles were incorporated into the optimized composite hydrogel containing nanohydroxy apatite (nHA). The combined hydrogel/nanoparticle systems displayed reasonable injectability with excellent gelation time at 37 °C. The optimum formulae sustained the release of linezolid for 7-10 days, which reveals its ability to reduce the frequency of injection during the course of treatment of bones infections and increase the patients' compliance. They succeeded to alleviate the bone infections and the associated clinical, biochemical, radiological, and histopathological changes within 2-4 weeks of injection. As to the state of art in this study and to the best of our knowledge, no such complete and systematic study on this type of combined in situ forming hydrogel loaded with spray-dried nanoparticles of linezolid is available yet in literatures.

Transdermal Delivery of Methotrexate Loaded in Chitosan Nanoparticles to Treat Rheumatoid Arthritis

INTRODUCTION

Methotrexate shows high efficiency in the treatment of Rheumatoid arthritis, but its adverse effects cannot be tolerated by many patients. Additionally, Methotrexate suffers from rapid clearance from blood. Polymeric nanoparticles were used to solve these problems including chitosan.

METHODS

Herein, a new nanoparticulate system to deliver Methotrexate (MTX) using chitosan nanoparticles (CS NPs) was developed to be used transdermally. CS NPs were prepared and characterized. The drug release was studied in vitro and ex vivo using rat skin. The drug performance in vivo was investigated on rats. Formulations were applied topically once a day on the paws and knee joints of arthritis rats for 6 weeks. Paw thickness was measured and synovial fluid samples were collected.

RESULTS

The results showed that CS NPs were monodispersed, and spherical with a size of 279.9 nm and a charge above ± 30mV. Further, 88.02% of MTX was entrapped in the NPs. CS NPs prolonged MTX release and enhanced its permeation (apparent permeability ⁓35.00cm/h) and retention (retention capacity ⁓12.01%) through rats' skin. The transdermal delivery of MTX-CS NPs improves the progress of the disease compared to free MTX, as reflected by the lower arthritic index values, lower proinflammatory cytokines (TNF-α and IL-6), and higher anti-inflammatory cytokine (IL-10) in the synovial fluid. Further, the oxidative stress activities were significantly higher in the group treated with the MTX-CS NPs, as indicated by GSH. Finally, MTX-CS NPs were more effective in reducing lipid peroxidation in synovial fluid.

CONCLUSION

In conclusion, loading Methotrexate in chitosan nanoparticles controlled its release and enhance its effectiveness against rheumatoid when applied dermally.

Novel anti-psoriatic nanostructured lipid carriers for the cutaneous delivery of luteolin: A comprehensive in-vitro and in-vivo evaluation

Psoriasis is a prevalent laborious inflammation in skin with alternate phases of remission and relapses. The current study sought to develop nanostructured lipid carriers (NLCs) having enhanced skin deposition as well as augmented anti-inflammatory potential, to repurpose the use of luteolin (Lut), a flavonoid, in the treatment of psoriasis. NLCs were prepared using different oils having reported anti-inflammatory activity and evaluated in terms of size, surface charge, entrapment efficiency, stability upon storage, in-vitro anti-inflammatory potential, surface morphology, in-vitro release profile and release kinetics, and ex-vivo skin deposition. In-vivo animal studies were conducted on the optimized formula using imiquimod-induced psoriasis rat model. The prepared NLCs were nanosized ranging from 202 to 538 nm, negatively charged with values having the range of -13.10 to -19.26 mV with high entrapment efficiency values ranging from 84.21 to 96.53% and high in-vitro anti-inflammatory potential compared to the blank and control formulations. Furthermore, NLCs demonstrated adequate storage stability demonstrated by slightly significant change in their colloidal properties. The prepared nanoparticles exhibited sustained drug release up to 24 h and succeeded in enhancing the skin deposition of Lut by 3.4-fold higher in stratum corneum, epidermis and dermis compared to Lut suspension with minimum transdermal delivery. In-vivo assessment of psoriasis was carried out morphologically, histopathologically and biochemically and results revealed significant augmentation of the anti-psoriatic efficacy of Lut upon its encapsulation in NLCs compared to free Lut suspension. The developed system proved to be an influential drug delivery system providing potent anti-psoriatic therapy, paving the way for futuristic clinical investigations.

Cytotoxicity Enhancement of α-Mangostin with Folate-Conjugated Chitosan Nanoparticles in MCF-7 Breast Cancer Cells

α-mangostin (AM) is a promising natural anticancer agent that can be used in cancer research. However, its effectiveness can be limited by poor solubility and bioavailability. To address this issue, chitosan-based nanoparticles (CSNPs) have been investigated as a potential delivery system to enhance the cytotoxicity to cancer cells and improve selectivity against normal cells. In this study, we developed folate-conjugated chitosan nanoparticles (F-CS-NPs) using a carbodiimide-based conjugation method to attach folate to chitosan (CS), which have different molecular weights. The NPs were crosslinked using tripolyphosphate (TPP) via ionic gelation. To characterize the F-CS-NPs, we utilized various analytical techniques, including transmission electron microscopy (TEM) to evaluate the particle size and morphology, Fourier-transform infrared spectroscopy (FTIR) to confirm the presence of functional groups, and ultraviolet-visible spectroscopy (UV-Vis) to measure the absorption spectrum and confirm the presence of folate. The particle size of AM-F-CS-NPs ranged from 180 nm to 250 nm, with many having favorable charges ranging from +40.33 ± 3.4 to 10.69 ± 1.3 mV. All NPs exhibited the same spherical morphology. The use of F-CS-NPs increased drug release, followed by a sustained release pattern. We evaluated the cytotoxicity of AM, AM-F-CS-HMW, and AM-F-CS-LMW NPs against MCF-7 cells and found IC50 values of 8.47 ± 0.49, 5.3 ± 0.01, and 4.70 ± 0.11 µg/mL, respectively. These results confirm the improved cytotoxicity of AM in MCF-7 cells when delivered via F-CS-NPs. Overall, our in vitro study demonstrated that the properties of F-CS-NPs greatly influence the cytotoxicity of AM in MCF-7 breast cancer cells (significantly different (p < 0.05)). The use of F-CS-NPs as a drug-delivery system for AM may have the potential to develop novel therapies for breast cancer.

Gentiopicroside-Loaded Chitosan Nanoparticles Inhibit TNF-α-Induced Proliferation and Inflammatory Response in HaCaT Keratinocytes and Ameliorate Imiquimod-Induced Dermatitis Lesions in Mice

Purpose

In this study, we aimed to report the biological characteristics of the first successful synthesis of gentiopicroside-loaded chitosan nanoparticles and to evaluate the therapeutic effects and preliminary mechanisms of gentiopicrin-loaded chitosan on psoriasis-like cell and mouse models.

Methods

Gentiopicroside-loaded chitosan nanoparticles (CHI-GEN) were prepared, and their biological characteristics were evaluated. HaCaT keratinocytes were stimulated with TNF-α to establish a psoriatic keratinocyte model. MTT assay and flow cytometry were used to measure cell viability and apoptosis, respectively. mRNA levels of K17, VEGF A, and IL-6 and IL-23A were detected using qRT-PCR. These tests were used to preliminarily assess the effects of CHI-GEN on keratinocyte proliferation and inflammation. Imiquimod was used to construct a psoriasis-like mice model. The severity of psoriasis was scored based on the psoriasis area severity index (PASI), H&E staining was used to observe the histological changes and the level of inflammation and cell proliferation of skin lesions was evaluated by measuring the mRNA levels of K17, IL-23A, and IL-17A using qRT-PCR.

Results

The average particle size of CHI-GEN nanoparticles was approximately 100 nm, and the zeta potential was 2.69 ± 0.87 mV. The cumulative release was 67.2% in solutions of pH 5.5 at 24 h. GEN reduced TNF-α-induced excessive proliferation of HaCaT keratinocytes and downregulated mRNA levels of K17, VEGF A, and inflammatory cytokines IL-6 and IL-23A, which was more obvious in the CHI-GEN treatment group. Additionally, CHI-GEN significantly improved the severity of skin lesions in psoriasis-like mice and downregulated the mRNA expressions of IL-6, IL-23A, and IL-17A in mice skin lesions.

Conclusion

In conclusion, we successfully prepared gentiopicrin-chitosan nanoparticles. Our results show that these nanoparticles have anti-psoriasis activity, inhibits keratinocyte proliferation and improves symptoms in psoriasis model mice and can be used to develop an effective strategy for the treatment of psoriasis.

Sustained Release Microneedles: Materials and Applications in Facial Rejuvenation

Wrinkled and loose skin resulting from collagen degradation along with fibers decreasing reflects the youth diminishing. Microneedles (MNs) have opened up new avenues for the development of painless and noninvasive transdermal drug delivery systems for facial rejuvenation. Encapsulated drugs or molecules are transmitted to targeted tissues via percutaneous microchannels, which eliminate potential gastric stimulation or first-pass metabolic effects, as well as boost patient compliance. Although MNs are considered effective and feasible therapeutic alternatives to metals, silicon, and polymers, traditional procedures with reduction processes continue to encounter methodological limitations. In recent years, promising additive manufacturing processes such as three-dimensional printing and two-photon polymerization manufacturing have been developed with the aim of overcoming the limitations by traditional processes to facilitate an efficient and economic production mode. This review summarizes the design, material selection, and manufacturing method for recently advanced MN systems. Furthermore, we also highlight specific polymeric or natural microneedle products, like hyaluronan, plant derivates, and vitamins, for esthetic applications in this review. Impact Statement In this review, the materials and manufactural routes of microneedles (MNs) are detailed. Moreover, similar to the diagnostic or therapeutic MNs, the feature of dispensation with training and ready-to-use is perfect for beautification and anti-aging, which necessitate repeated and long-term usage. Furthermore, the specific polymeric or natural products for esthetic applications of MNs are highlighted in this review.

Efficient Whole-Cell Biotransformation for α-Arbutin Production through the Engineering of Sucrose Phosphorylase Combined with Engineered Cell Modification

α-Arbutin is extensively used in cosmetic industries. The lack of highly active enzymes and the cytotoxicity of hydroquinone limit the biosynthesis of α-arbutin. In this study, a whole-cell biocatalytic approach based on enzyme engineering and engineered cell modification was identified as effective in enhancing α-arbutin production. First, a sucrose phosphorylase (SPase) mutant with higher enzyme activity was obtained by experimental screening. Next, to avoid the oxidation of hydroquinone, we established an anaerobic process to improve the robustness of the cells by knocking out lytC, sdpC, and skfA in Bacillus subtilis and overcoming the inhibitory effect of a high concentration of hydroquinone. Finally, the engineered strain was used for biotransformation in a 5 L fermenter with batch feeding for 24 h. The final yield of α-arbutin achieved was 129.6 g/L, which may provide a basis for the large-scale industrial production of α-arbutin.

Hyaluronic Acid Hydrogel Containing Resveratrol-Loaded Chitosan Nanoparticles as an Adjuvant in Atopic Dermatitis Treatment

Atopic dermatitis (AD) is a common disease-causing skin inflammation, redness, and irritation, which can eventually result in infection that drastically impacts patient quality of life. Resveratrol (Res) is a natural phytochemical famed for its excellent anti-inflammatory and antioxidant activities. However, it is poorly bioavailable. Thus, a drug delivery system is needed to enhance in vivo bioactivity. Herein, we report the preparation of hyaluronic acid (HA) hydrogels containing resveratrol-loaded chitosan (CS) nanoparticles, their physicochemical analysis, and their potential therapeutic effects in the treatment of AD. Positively charged CS nanoparticles prepared by tripolyphosphate (TPP) gelation showed sizes ranging from 120 to around 500 nm and Res encapsulation efficiency as high as 80%. Embedding the nanoparticles in HA retarded their hydrolytic degradation and also slowed resveratrol release. Resveratrol released from nanoparticle-loaded hydrogel counteracted the oxidative damage induced by ROS generation in TNF-α/INF-γ-treated human keratinocytes (HaCaT) used as an AD in vitro model. Moreover, pre-treatment with Res@gel reduced secretion and gene expression of proinflammatory cytokines in HaCaT cells. The physicochemical analysis and in vitro assay confirmed that the formulated hydrogel could be considered an efficient and sustained resveratrol delivery vector in AD treatment.

Development and Characterization of Thermal Water Gel Comprising Helichrysum italicum Essential Oil-Loaded Chitosan Nanoparticles for Skin Care

Helichrysum italicum essential oil (H. italicum EO) is recognized for its anti-inflammatory, antimicrobial and wound-healing properties. The main goal of the present work was the development and characterization of a gel formulation comprising H. italicum EO loaded in chitosan nanoparticles (NPs) for dermatological applications. H. italicum EO-loaded chitosan NPs presented hydrodynamic diameter and PdI of about 300 nm and 0.28, respectively, and a surface charge of +19 mV. The H. italicum EO-loaded chitosan NPs were prepared by means of ionic gelation and then incorporated into a thermal water gel formulation. The organoleptic and physicochemical properties of the developed gel were studied. The gel remained stable under accelerated test conditions, maintaining pH, viscosity and organoleptic properties. In addition, the formulation presented pH, viscosity and spreadability properties suitable for topical application. Finally, the performance of the gel in topical application was evaluated on the skin of volunteers using non-invasive methods, particularly, by means of biometric evaluation. These assays showed that the properties of the developed thermal water-based gel formulation with H. italicum EO-loaded chitosan NPs can improve skin hydration and maintain healthy skin conditions, demonstrating its putative role for distinct dermatological applications.

Novel Chitosan Nanoparticles Loaded with Methotrexate for Topical Treatment of Psoriasis

AIMS

In this work, CS NPs were prepared by the ionic gelation method and encapsulated with MTX to treat psoriasis dermally.

BACKGROUND

A major drawback of using MTX to treat psoriasis is its limited diffusion through the skin, which may cause insufficient penetration of MTX into the basal layer of the epidermis, where psoriatic cells are generated.

OBJECTIVE

Nanoparticles have been used to enhance MTX diffusion through the skin. The system prepared in this work is expected to direct the drug to psoriasis cells by enhancing the drug diffusion through the skin, which will increase the amount of the drug reaching the epidermis. This is expected to enhance the effectiveness of the drug and to decrease its systemic side effects.

METHODS

Five formulations of Chitosan nanoparticles were prepared and loaded with Methotrexate using the ionic gelation technique. Particle size, dispersity, charge, loading capacity and encapsulation efficacy were measured. Characterization of prepared nanoparticles was conducted to confirm the formation of CS-NPs, successful encapsulation of MTX and its compatibility with other formulation components. In vitro drug release from CS-NPs, its permeation and accumulation in rats' skin were explored. Finally, the anti-psoriatic activity was assessed using the "mouse tail model."

RESULTS

The results showed that the sizes ranged from 132.13 ± 0.70 to 300.60 ± 4.81 nm, where SEM demonstrated the spherical and uniform distribution of the NPs. The surface charge of all NPs was highly positive and ranged from 20.22 ± 1.10 to 30.90 ± 0.70 mV. Further, the EE% and LC% of the nanoparticles were in the range of 77.72%-92.70% and 17.90%-21.81%, respectively. in vitro, the release of methotrexate from the nanoparticles was sustained. Additionally, both the permeation and retention of drugs within the skin were enhanced significantly using this system. Eventually, orthokeratosis% and drug activity% showed significant superiority of MTX-CS NPs over the free drug in treating psoriasis in model mice.

CONCLUSION

In conclusion, MTX-CS NPs can be used to enhance the treatment of psoriasis topically.

Decrypting the Potential of Nanotechnology-Based Approaches as Cutting-Edge for Management of Hyperpigmentation Disorder

The abundant synthesis and accretion of melanin inside skin can be caused by activation of melanogenic enzymes or increase in number of melanocytes. Melasma is defined as hyperpigmented bright or dark brown spots which are symmetrically distributed and have serrated and irregular borders. The three general categories of pigmentation pattern include centro facial pattern, malar pattern, and mandibular pattern. Exposure to UV rays, heat, use of cosmetics and photosensitizing drugs, female sex hormonal therapies, aberrant production of melanocyte stimulating hormone, and increasing aesthetic demands are factors which cause the development of melasma disease. This review gives a brief overview regarding the Fitzpatrick skin phototype classification system, life cycle of melanin, mechanism of action of anti-hyperpigmenting drugs, and existing pharmacotherapy strategies for the treatment of melasma. The objectives of this review are focused on role of cutting-edge nanotechnology-based strategies, such as lipid-based nanocarriers, i.e., lipid nanoparticles, microemulsions, nanoemulsions, liposomes, ethosomes, niosomes, transfersomes, aspasomes, invasomes penetration-enhancing vesicles; inorganic nanocarriers, i.e., gold nanoparticles and fullerenes; and polymer-based nanocarriers i.e., polymeric nanoparticles, polymerosomes, and polymeric micelles for the management of hyperpigmentation.