Optimization and evaluation of pluronic lecithin organogels as a transdermal delivery vehicle for sinomenine

Lecithin Organogel: A Promising Carrier for the Treatment of Skin Diseases

Skin is the largest organ of the human body, as it protects the body from the external environment. Nowadays, skin diseases and skin problems are more common, and millions of people are affected daily. Skin diseases are due to numerous infectious pathogens or inflammatory conditions. The increasing demand for theoretical research and practical applications has led to the rising prominence of gel as a semisolid material. To this end, organogels has been widely explored due to their unique composition, which includes organic solvents and mineral or vegetable oils, among others. Organogels can be described as semisolid systems wherein an organic liquid phase is confined within a three-dimensional framework consisting of self-assembled, cross-linked, or entangled gelator fibers. These gels have the ability to undergo significant expansion and retain substantial amounts of the liquid phase, reaching up to 99% swelling capacity. Furthermore, they respond to a range of physical and chemical stimuli, including temperature, light, pH, and mechanical deformation. Notably, due to their distinctive properties, they have aroused significant interest in a variety of practical applications. Organogels favor the significant encapsulation and enhanced permeation of hydrophobic molecules when compared with hydrogels. Accordingly, organogels are characterized into lecithin organogels, pluronic lecithin organogels, sorbitan monostearate-based organogels, and eudragit organogels, among others, based on the nature of their network and the solvent system. Lecithin organogels contain lecithin (natural and safe as a living cell component) as an organogelator. It acts as a good penetration enhancer. In this review, first we have summarized the fundamental concepts related to the elemental structure of organogels, including their various forms, distinctive features, methods of manufacture, and diverse applications. Nonetheless, this review also sheds light on the delivery of therapeutic molecules entrapped in the lecithin organogel system into deep tissue for the management of skin diseases and provides a synopsis of their clinical applications.

A review on pharmacokinetics of sinomenine and its anti-inflammatory and immunomodulatory effects

Autoimmune diseases (ADs), with significant effects on morbidity and mortality, are a broad spectrum of disorders featured by body's immune responses being directed against its own tissues, resulting in chronic inflammation and tissue damage. Sinomenine (SIN) is an alkaloid isolated from the root and stem of Sinomenium acutum which is mainly used to treat pain, inflammation and immune disorders for centuries in China. Its potential anti-inflammatory role for treating immune-related disorders in experimental animal models and in some clinical applications have been reported widely, suggesting an inspiring application prospect of SIN. In this review, the pharmacokinetics, drug delivery systems, pharmacological mechanisms of action underlying the anti-inflammatory and immunomodulatory effects of SIN, and the possibility of SIN as adjuvant to disease-modifying anti-rheumatic drugs (DMARDs) therapy were summarized and evaluated. This paper aims to reveal the potential prospects and limitations of SIN in the treatment of inflammatory and immune diseases, and to provide ideas for compensating its limitations and reducing the side effects, and thus to make SIN better translate to the clinic.

Recent Advancements in Drug Delivery of Sinomenine, A Disease-Modifying Anti-Rheumatic Drug

Sinomenine (SIN) is a benzyltetrahydroisoquinoline-type alkaloid isolated from the dried plant root and stem of Sinomenium acutum (Thumb.) Rehd.et Wils, which shows potent anti-inflammatory and analgesic effects. As a transforming disease-modifying anti-rheumatic drug, SIN has been used to treat rheumatoid arthritis over twenty-five years in China. In recent years, SIN is also in development for use against other disorders, including colitis, pain, traumatic brain injury, and uveitis. However, its commercial hydrochloride (SIN-HCl) shows low oral bioavailability and certain allergic reactions in patients, due to the release of histamine. Therefore, a large number of pharmaceutical strategies have been explored to address these liabilities, such as prolonging release behaviors, enhancing skin permeation and adsorption for transdermal delivery, targeted SIN delivery using new material or conjugates, and co-amorphous technology. This review discusses these different delivery strategies and approaches employed to overcome the limitations of SIN for its efficient delivery, in order to achieve improved bioavailability and reduced side effects. The potential advantages and limitations of SIN delivery strategies are elaborated along with discussions of potential future SIN drug development strategies.

Correlation between in vivo microdialysis pharmacokinetics and ex vivo permeation for sinomenine hydrochloride transfersomes with enhanced skin absorption

Transdermal drug delivery systems have drawn increasing attention in recent decades. Estimation of the correlation between ex vivo permeation and in vivo absorption (EVIVC) is an indispensable issue in the research and development of transdermal pharmaceutical products. In this paper, sinomenine hydrochloride (SH) transfersomes (SHTs) were prepared with sodium deoxycholate as edge activator, while SH liposomes (SHLs) were prepared as a control preparation. The transdermal permeation characteristics differences between them were explored by an ex vivo skin permeation experiment with Franz diffusion cell and an in vivo skin/blood pharmacokinetic experiment facilitated by double-sited microdialysis sampling technique. The curves of percentage absorbed versus time (absorption curves) under the skin and in the blood were plotted according to the percentages calculated by the deconvolution approach with the application of Wagner-Nelson model, and were correlated with the ex vivo permeation curves to evaluate a level A correlation, while a level C correlation evaluation was conducted based on the in vivo steady-state blood concentration (C_ss) and the ex vivo steady-state transdermal permeation rate. The ex vivo permeation test indicated that the cumulative transdermal permeated amount of SH at 36 h in SHTs was about 1.7 times of that in SHLs. The skin pharmacokinetic data showed that the C_ss and AUC_0-t of SHTs were about 8.8 and 8.0 times of those of SHLs, respectively, and the MRT_0-t of SHTs was shorter. The blood pharmacokinetic data showed that the C_ss and AUC_0-t of SHTs were about 3.7 and 2.9 times of those of SHLs, respectively. The in vivo absorption curves were correlated well with the ex vivo permeation curves. The squares of correlation coefficient (R²) for SHTs and SHLs were 0.9153 and 0.9355 respectively in the skin, were 0.8536 and 0.7747 respectively in the blood. As to level C EVIVC, there was no significant difference between the predicted C_ss from ex vivo and the measured C_ssin vivo. The transfersomes can be employed as effective vehicles to promote the transdermal absorption of SH, and it is feasible to predict the in vivo skin/blood pharmacokinetic properties of SHLs and SHTs based on the ex vivo skin permeation characteristics.

A Review of Potential Use of Amazonian Oils in the Synthesis of Organogels for Cosmetic Application

New strategies for the delivery of bioactives in the deeper layers of the skin have been studied in recent years, using mainly natural ingredients. Among the strategies are organogels as a promising tool to load bioactives with different physicochemical characteristics, using vegetable oils. Studies have shown satisfactory skin permeation, good physicochemical stability mainly due to its three-dimensional structure, and controlled release using vegetable oils and low-molecular-weight organogelators. Within the universe of natural ingredients, vegetable oils, especially those from the Amazon, have a series of benefits and characteristics that make them unique compared to conventional oils. Several studies have shown that the use of Amazonian oils brings a series of benefits to the skin, among which are an emollient, moisturizing, and nourishing effect. This work shows a compilation of the main Amazonian oils and their nutraceutical and physicochemical characteristics together with the minority polar components, related to health benefits, and their possible effects on the synthesis of organogels for cosmetic purposes.

Optical Coherence Tomography and Microdialysis for Microneedle-Mediated Penetration Enhancement Study of Paeoniflorin-Loaded Ethosomes

BACKGROUND

To understand the cumulative effect of topical formulations after medication, evaluate the therapeutic effect of microneedle-assisted (MN-assisted) paeoniflorin-loaded ethosomes (TGP-E), and explore the potential for deep penetration of drugs, this paper uses microdialysis to systematically study the percutaneous pharmacokinetics of TGP-E.

METHODS

First, optical coherence tomography (OCT) was used to study the effectiveness of microneedle puncture. Second, a microdialysis method and a UPLC-MS method for determining the amount of paeoniflorin (Pae) in dialysate were established. Finally, the transdermal pharmacokinetics of TGP-E was studied using in vivo microdialysis in rats under the above MN-assisted conditions.

RESULTS

The optimal MN-assisted conditions were obtained at a microneedle length of 500 μm, a pressure of 3 N, and an action time of 3 min. The pharmacokinetic results demonstrated that the maximum drug concentration (Cmax) and the area under the curve (AUC) of the TGP-E gel were higher than the TGP-saline solution gel, and the mean retention time was lower. These indicated that microneedle can promote the entry of the ethosomes into the skin for in vivo experiments and greatly improve the possibility of deep penetration of the water-soluble Pae.

CONCLUSION

Therefore, the microneedle-ethosomes delivery system is a more ideal means for promoting the deep penetration of Pae. These findings may provide a reference for the combination of multiple penetration-enhancement ways to promote drug absorption, and also provide a new insight to realize the development of novel, safe, and more effective dosage forms and administration routes of drugs.

Nanocarriers for Topical Drug Delivery: Approaches and Advancements

Background:

Delivery of drugs through the skin has been an attractive as well as a challenging area for research. Topical drug delivery has provided enormous advantages over the systemic route for various drugs and one of the important amongst them is reduced toxicity due to a minimum or zero exposure to non-target organs.

Methods:

Various nanocarrier loaded topical preparations including organogels, emulgels, niosomal gel, lyotropic liquid crystal based gels, etc have been investigated for their topical application. Nanocarriers loaded topical preparation have been proven for improved permeation through the cutaneous barrier and delivering the drug at the target site. The objective of this review is to study the recent updates regarding newer topical gel formulations and highlighting their current potential and future scope of the same.

Results:

The present work has summarized different studies related to nanotechnology derived topical gel formulations and also enlisted few drugs which have been successfully formulated as novel topical gels. Advancement in nanocarriers loaded topical preparations have also been reviewed with their permeation and efficacy compared to conventional formulations.

Conclusion:

The present review will provide an overview of nanotechnology based topical preparation to the readers and will create curiosity for further development.

Novel application of pluronic lecithin organogels (PLOs) for local delivery of synergistic combination of docetaxel and cisplatin to improve therapeutic efficacy against ovarian cancer

The synergistic combination of docetaxel (DTX) and cisplatin (CIS) by local drug delivery with a pluronic lecithin organogel (PLO) to facilitate high drug concentrations at tumor sites and less nonspecific distribution to normal organs is thought to be beneficial in chemotherapy. In this study, using Capryol-90 (C90) with the addition of lecithin as the oil phase was developed to carry DTX, which was then incorporated into a PLO-containing CIS to formulate a dual-drug injectable PLO for local delivery. An optimal PLO composite, P₁₃L_0.15O_1.5, composed of PF127:lecithin:C90 at a 13:0.15:1.5 weight ratio was obtained. The sol-gel transition temperature of P₁₃L_0.15O_1.5 was found to be 33 °C. Tumor inhibition studies illustrated that DTX/CIS-loaded P₁₃L_0.15O_1.5 could efficiently suppress tumor growth by both intratumoral and peritumoral injections in SKOV-3 xenograft mouse model. Pharmacokinetic studies showed that subcutaneous administration of P₁₃L_0.15O_1.5 was able to sustain the release of DTX and CIS leading to their slow absorption into the systemic circulation resulting in lower area under the plasma concentration curve at 0-72 h (AUC_0-72) and maximum concentration (C_max) values but longer half-life (T_1/2) and mean residence time (MRT) values. An in vivo biodistribution study showed lower DTX and CIS concentrations in organs compared to other treatment groups after IT administration of the dual drug-loaded P₁₃L_0.15O_1.5. It was concluded that the local co-delivery of DTX and CIS by PLOs may be a promising and effective platform for local anticancer drug delivery with minimal systemic toxicities.

Sinomenine hydrochloride-loaded dissolving microneedles enhanced its absorption in rabbits

Sinomenine hydrochloride-loaded dissolving microneedles (SH-DM) were fabricated by maltose and poly-lactic-co-glycolic acid using a casting method. The mechanical strength of SH-DM was investigated by an insertion test. In vivo transdermal absorption experiment was performed to evaluate the percutaneous absorption of SH-DM, sinomenine hydrochloride gel (SH-G) was used as a control. The results demonstrated that prepared SH-DM was morphologically intact with sufficient mechanical strength after inserting into aluminum foil and rat skin. The value of area under curve obtained after administration of SH-DM through transdermal in rabbits showed a significantly rise and was 1.99 times higher than that of SH-G, and the relative bioavailability value was 199.21%. These results showed that SH-DM enhanced bioavailability and permeability of SH.