Edge activated ultradeformable liposomes of psoralen and its derivatives: Development and comparative evaluation for vitiligo therapy

Bergapten: A review of its pharmacology, pharmacokinetics, and toxicity

Bergapten is a natural furocoumarin, also known as 5-methoxypsoralen, and its medicinal value has been paid more and more attention. By sorting out the pharmacological literature of bergapten, we found that bergapten has a wide range of pharmacological effects, including neuroprotection, organ protection, anticancer, antiinflammatory, antimicrobial, and antidiabetes effects. However，bergapten has complex impacts on the hepatic metabolic enzyme. Moreover, pharmacokinetic studies showed that bergapten has higher absolute bioavailability and can cross the blood-brain barrier and has a great potential for treating brain disease, but the mechanism needs further clarification to make greater use of its ability to treat brain diseases. Furthermore, the phototoxicity of bergapten combined with ultraviolet light has always been mentioned. In view of its wide range of pharmacological activities, bergapten is expected to be a potential drug candidate for the treatment of diabetes and diabetes-induced osteoporosis, epilepsy, Alzheimer's disease, depression, and cancer. However, further studies are needed to elucidate its molecular mechanisms and targets. The phototoxicity of bergapten as a side effect should be further avoided. On the other hand, the photoactivation of bergapten in the anticancer aspect can be better utilized.

Liposomes Loaded with Unsaponifiable Matter from Amaranthus hypochondriacus as a Source of Squalene and Carrying Soybean Lunasin Inhibited Melanoma Cells

Amaranthus hypochondriacus is a source of molecules with reported health benefits such as antioxidant activity and cancer prevention. The objective of this research was to optimize the conditions for preparing a liposome formulation using amaranth unsaponifiable matter as a source of squalene in order to minimize the particle size and to maximize the encapsulation efficiency of liposomes for carrying and delivering soybean lunasin into melanoma cell lines. Amaranth oil was extracted using supercritical dioxide carbon extraction (55.2 MPa pressure, 80 °C temperature, solvent (CO₂)-to-feed (oil) ratio of 20). The extracted oil from amaranth was used to obtain the unsaponifiable enriched content of squalene, which was incorporated into liposomes. A Box–Behnken response surface methodology design was used to optimize the liposome formulation containing the unsaponifiable matter, once liposomes were optimized. Soybean lunasin was loaded into the liposomes and tested on A-375 and B16-F10 melanoma cells. The squalene concentration in the extracted oil was 36.64 ± 0.64 g/ 100 g of oil. The particle size in liposomes was between 115.8 and 163.1 nm; the squalene encapsulation efficiency ranged from 33.14% to 76.08%. The optimized liposome formulation contained 15.27 mg of phospholipids and 1.1 mg of unsaponifiable matter. Cell viability was affected by the liposome formulation with a half-maximum inhibitory concentration (IC₅₀) equivalent to 225 μM in B16-F10 and 215 μM in A-375. The liposomes formulated with lunasin achieved 82.14 ± 3.34% lunasin encapsulation efficiency and improved efficacy by decreasing lunasin IC₅₀ by 31.81% in B16-F10 and by 41.89% in A-375 compared with unencapsulated lunasin.

Nanoliposomes@Transcutol for In Vitro Skin Delivery of 8-Methoxypsoralen

8-methoxypsoralen is the most common drug in psoralen plus ultraviolet light irradiation therapy for the treatment of severe psoriasis. Despite of the efficacy, its classic oral administration leads to several serious adverse effects. However, the topical psoralen application produces a drug skin accumulation lower than that obtained by oral administration, due to the drug low skin permeability. In this paper, 8-methoxypsoralen loaded Penetration Enhancer-containing Vesicles were prepared using soy phosphatidylcholine and the penetration enhancer Transcutol® (5% or 10%) and characterized in terms of size, polydispersity index, zeta potential and encapsulation efficiency. No statistically significant differences in both size (~135 nm) and encapsulation efficiency (~65%) were found for different Transcutol® concentration. Transdermal delivery study assessed by Franz diffusion cells, showed that the 8-methoxypsoralen mainly accumulated into the stratum corneum. Moreover, after Penetration Enhancer-containing Vesicles application, the drug recovered in this layer is almost double of that delivered by conventional liposomes, while no significant difference was found from the different Transcutol® concentrations. Finally, biocompatibility checked by an MTT assay, demonstrated that the incubation of human keratinocytes for 24 h with 8-methoxypsoralen loaded Penetration Enhancer-containing Vesicles did not significantly reduce cell viability.

Nano-Lipid-Carriers for the Treatment of Vitiligo: A Recent Update, Pathophysiology and Mechanism of Drug Delivery

BACKGROUND

Vitiligo is an auto-immune disease with white-coloured disfiguring patches or spots on the skin surface. It is highly prevalent in several corners of the world. This disease spreads in different age groups.

AIM

The main aim of this review is to provide an overview of pathophysiology and lipid-based nano-carriers for the treatment of vitiligo.

METHODS

The conventional delivery systems available have limited efficacy due to less retention of the drug in the epidermal layer where melanocytes reside. In order to overcome these issues, an advanced delivery system with lipid-based nano-carriers for the treatment of vitiligo was proven to be better as per the literature explored.

RESULTS

This review summarizes the pathophysiology along with novel lipid-based nano-carriers for the treatment of vitiligo.

CONCLUSION

Though various treatment regimens are present for the disease, nano-lipid carrier systems are significantly gaining importance nowadays, due to their high effectivity in topically acting on the target site. Nano-lipid carrier systems such as liposomes, ethosomes, transethosomes and transferosomes can be said to be at the top of the list in acting effectively against vitiligo or several other tropical diseases.

Nanocarriers for treatment of dermatological diseases: Principle, perspective and practices

Skin diseases are the fourth leading non-fatal skin conditions that act as a burden and affect the world economy globally. This condition affects the quality of a patient's life and has a pronounced impact on both their physical and mental state. Treatment of these skin conditions with conventional approaches shows a lack of efficacy, long treatment duration, recurrence of conditions, systemic side effects, etc., due to improper drug delivery. However, these pitfalls can be overcome with the applications of nanomedicine-based approaches that provide efficient site-specific drug delivery at the target site. These nanomedicine-based strategies are evolved as potential treatment opportunities in the form of nanocarriers such as polymeric and lipidic nanocarriers, nanoemulsions along with emerging others viz. carbon nanotubes for dermatological treatment. The current review focuses on challenges faced by the existing conventional treatments along with the topical therapeutic perspective of nanocarriers in treating various skin diseases. A total of 213 articles have been reviewed and the application of different nanocarriers in treating various skin diseases has been explained in detail through case studies of previously published research works. The toxicity related aspects of nanocarriers are also discussed.

Transcutol® P Containing SLNs for Improving 8-Methoxypsoralen Skin Delivery

Topical psoralens plus ultraviolet A radiation (PUVA) therapy consists in the topical application of 8-methoxypsoralen (8-MOP) followed by the skin irradiation with ultraviolet A radiation. The employment of classical 8-MOP vehicles in topical PUVA therapy is associated with poor skin deposition and weak skin permeability of psoralens, thus requiring frequent drug administration. The aim of the present work was to formulate solid lipid nanoparticles (SLNs) able to increase the skin permeation of 8-MOP. For this purpose, the penetration enhancer Transcutol^® P (TRC) was added to the SLN formulation. SLNs were characterized with respect to size, polydispersity index, zeta potential, entrapment efficiency, morphology, stability, and biocompatibility. Finally, 8-MOP skin diffusion and distribution within the skin layers was investigated using Franz cells and newborn pig skin. Freshly prepared nanoparticles showed spherical shape, mean diameters ranging between 120 and 133 nm, a fairly narrow size distribution, highly negative ζ potential values, and high entrapment efficiency. Empty and loaded formulations were almost stable over 30 days. In vitro penetration and permeation studies demonstrated a greater 8-MOP accumulation in each skin layer after SLN TRC 2% and TRC 4% application than that after SLN TRC 0% application. Finally, the results of experiments on 3T3 fibroblasts showed that the incorporation of TRC into SLNs could enhance the cellular uptake of nanoparticles, but it did not increase their cytotoxicity.

Development, Characterization and Use of Liposomes as Amphipathic Transporters of Bioactive Compounds for Melanoma Treatment and Reduction of Skin Inflammation: A Review

The skin is the largest organ in the human body, providing a barrier to the external environment. It is composed of three layers: epidermis, dermis and hypodermis. The most external epidermis is exposed to stress factors that may lead to skin conditions such as photo-aging and skin cancer. Some treatments for skin disease utilize the incorporation of drugs or bioactive compounds into nanocarriers known as liposomes. Liposomes are membranes whose sizes range from nano to micrometers and are composed mostly of phospholipids and cholesterol, forming similar structures to cell membranes. Thus, skin treatments with liposomes have lower toxicity in comparison to traditional treatment routes such as parenteral and oral. Furthermore, addition of edge activators to the liposomes decreases the rigidity of the bilayer structure making it deformable, thereby improving skin permeability. Liposomes are composed of an aqueous core and a lipidic bilayer, which confers their amphiphilic property. Thus, they can carry hydrophobic and hydrophilic compounds, even simultaneously. Current applications of these nanocarriers are mainly in the cosmetic and pharmaceutic industries. Nevertheless, new research has revealed promising results regarding the effectiveness of liposomes for transporting bioactive compounds through the skin. Liposomes have been well studied; however, additional research is needed on the efficacy of liposomes loaded with bioactive peptides for skin delivery. The objective of this review is to provide an up-to-date description of existing techniques for the development of liposomes and their use as transporters of bioactive compounds in skin conditions such as melanoma and skin inflammation. Furthermore, to gain an understanding of the behavior of liposomes during the process of skin delivery of bioactive compounds into skin cells.

Physicochemical Investigation of Psoralen Binding to Double Stranded DNA through Electroanalytical and Cheminformatic Approaches

This work showcased the first physicochemical investigation of psoralen (PSO) binding to double stranded DNA (dsDNA) through electroanalytical methods. Results evidenced that PSO presents one non-reversible anodic peak at electric potential (E_pa) ≈ 1.42 V, which is associated with its oxidation and the formation of an epoxide derivative. Moreover, PSO analytical signal (i.e., faradaic current) decreases linearly with the addition of dsDNA, while the electric potential associated to PSO oxidation shifts towards more positive values, indicating thence that dsDNA addition hinders PSO oxidation. These findings were corroborated by the chemoinformatic study, which evidenced that PSO intercalated noncovalently at first between base-pairs of the DNA duplex, and then irreversibly formed adducts with both DNA strands, leading up to the formation of a cross-link which bridges the DNA helix, which explains the linear dependence between the faradaic current generated by PSO oxidation and the concentration of DNA in the test-solution, as well as the dependence between E_p and the addition of dsDNA solution. Therefore, the findings herein reported evidence of the applicability of electroanalytical approaches, such as voltammetry in the study of DNA intercalating agents.

Fenoldopam mesylate for treating psoriasis: A new indication for an old drug

Fenoldopam, a highly selective dopamine receptor agonist, is available in clinics as Corlopam™ i.v. for the management of severe hypertension. Recent reports demonstrate its anti-proliferative activity in vitro in a dose dependent manner. However, stability issues of the drug due to its susceptibility to oxidation, pH sensitivity, poor transdermal flux, and the barrier properties of skin present challenges to develop a topical formulation of fenoldopam. The aim of the present study is to suggest a stable topical formulation of fenoldopam for the treatment of psoriasis. Water washable ointment and glycerin-based carbopol anhydrous gel of fenoldopam intended for topical delivery were prepared and evaluated in vitro and in vivo. Results from pH dependent stability studies suggest the necessity to maintain acidic pH in final formulations. The presence of an acidic adjuster in ointment and unneutralised carbopol dispersion of anhydrous gel maintain the desired acidic environment in the formulations. Stability studies of prepared formulations performed for 90 days indicate that the drug remains stable in formulations. In vivo studies demonstrate the applicability of the formulations for better skin penetration, skin compliance, and photosafety. Efficacy studies using an imiquimod induced psoriasis model confirm the promising application of developed fenoldopam topical formulations for psoriasis.

Preparation and Comparison of Oral Bioavailability for Different Nano-formulations of Olaparib

Olaparib (OLA) is a poly ADP ribose polymerase (PARP) inhibitor approved for germline BRCA-mutated (gBRCAm) advanced ovarian cancer and breast cancer. Low oral bioavailability of this drug requires increase in the dose and frequency causing haematological toxicity in the patients. The purpose of this study is to prepare different nano-formulations of OLA lipospheres (LP) by melt dispersion and nano-suspensions (NSP) by solvent evaporation (SE) and wet milling (WM) techniques and compare oral bioavailability of these formulations. Size of the nano-formulations OLA-LP, OLA-NSP_SE and OLA-NSP_WM were found to be 126.71 ± 4.54, 128.6 ± 2.34 and 531.1 ± 5.34 nm with polydispersity index below 0.3. In vitro release studies were performed by dialysis bag method where the sustained drug release was observed from nano-formulations until 9 h with Higuchi for OLA suspended in 2.5% w/v sodium carboxy methyl cellulose (OLA-SP), OLA-LP and OLA-NSP_WM and Peppas for OLA-NSP_SE-based drug release kinetics. In vivo pharmacokinetic studies, haematological toxicity and distribution studies were performed on rats. Results showed that there was an improvement in C_max, AUC_total, t_1/2 and MRT by OLA nano-formulations when compared with OLA-SP. OLA-SP has shown reduction in WBC, platelets and lymphocytes at 12 and 36 h time points; however, no reduction in cell count was observed with OLA nano-formulations. Distribution studies proved FITC nano-formulations were most rapidly absorbed and distributed when compared with FITC-loaded suspension. From the above results, it was concluded that OLA nano-formulations can be an alternative to enhance the oral bioavailability and to reduce the haematological toxicity of OLA.