It has been estimated that every year, millions of people are affected by neurodegenerative disorders, which complicate their lives and their caregivers’ lives. To date, there has not been an approved pharmacological approach to provide the complete treatment of neurodegenerative disorders. The only available drugs may only relieve the symptoms or slow down the progression of the disease. The absence of any treatment is quite rational given that neurodegeneration occurs by the progressive loss of the function or structure of the nerve cells of the brain or the peripheral nervous system, which eventually leads to their death either by apoptosis or necrotic cell death. According to a recent study, even though adult brain cells are injured, they can revert to an embryonic state, which may help to restore their function. These interesting findings might open a new path for the development of more efficient therapeutic strategies to combat devastating neurodegenerative disorders. Gene and protein therapies have emerged as a rapidly growing field for various disorders, especially neurodegenerative diseases. Despite these promising therapies, the complete treatment of neurodegenerative disorders has not yet been achieved. Therefore, the aim of this review is to address the most up-to-date data for neurodegenerative diseases, but most importantly, to summarize the available delivery systems incorporating proteins, peptides, and genes that can potentially target such diseases and pass into the blood–brain barrier. The authors highlight the advancements, at present, on delivery based on the carrier, i.e., lipid, polymeric, and inorganic, as well as the recent studies on radiopharmaceutical theranostics.

The goal of this study was to see if microemulsions might be used as a transdermal drug delivery system for acemetacin (ACM). Microemulsions containing isopropyl myristate, Tween 80, Transcutol HP, Labrafil M1944 CS, ethanol, and distilled water were used to create pseudo-ternary phase diagrams. In microemulsion systems, the ultimate concentration of ACM was 1% (w/w). Conductivity, droplet size, zeta potential, polydispersity index, viscosity, and pH were used to characterize the microemulsions. Furthermore, in vitro permeability investigations were carried out utilizing diffusion cells derived from the dorsal skin of mice. The results of characterization studies such as droplet size, polydispersity index, zeta potential, conductivity values of ideal formulation were found 9.107 ± 1.588 nm, 0.283 ± 0.062, −0.313 ± 0.006 mV, 0.018 ± 0.012 µS/cm, respectively. The penetration of ACM from ideal formulation was greater than the other developed formulations. The anti-inflammatory effect of ACM was evaluated in mice using the paw edema test. In addition, all test microemulsions had a significant analgesic effect in the hot plate and tail-flick tests as compared to the control. Finally, microemulsion formulations might be used to deliver ACM transdermally. Graphical Abstract

Objective: The purpose of this study is to create dexpanthenol-loaded hydrogel formulations to alter the release patterns and enhance the physicochemical qualities of the market product. Material and Method: To make hydrogel formulations, Carbopol Ultrez was utilized in concentrations of 1%, 1.5%, and 2% (w/w). The active component dexpanthenol was then added to the formulations at a concentration of 5% (w/w). pH, viscosity, texture profile analysis, spreadability, bioadhesion, and in vitro release characteristics were all assessed for the formulations. Result and Discussion: The formulations were found to be suitable for cutaneous application. TPA analysis revealed that the G1 and G1-DXP formulations had the hardness value 10.1851.219 and 30.8541.637 g, respectively. That formulations’ bioadhesion strength has grown because they are more flexible than previous formulations while having low hardness values. As such, it has been observed that the formulations release more than 50% of DXP in three hours while the market preparation was not even reach the 10% drug release. In the in vitro release kinetics study, it was calculated that all formulations fit the Higuchi model. As a result, a more effective drug delivery system has been developed compared to the market preparation. The currently prepared formulations are also promising formulations in terms of their use in treatment.

In recent years, the hydrophobic active substances have led researchers to develop new formulations to enhance bioavailability and dissolution rate; brinzolamide, a lipophilic drug belongs to carbonic anhydrase inhibitors, which cause reduction of intraocular pressure in patients suffering from glaucoma. Currently, the marketed product of brinzolamide is in the form of ocular drops; nonetheless, the conventional drops provide decreased therapeutic efficacy owing to their low bioavailability and pulsed drug release. Thus, the development of novel ocular formulations such as topical microemulsions is of high importance. In this work, the preparation of new microemulsions containing brinzolamide (0.2, 0.5 and 1% w/w) and comprised from isopropyl myristate, tween 80 and span 20 and Cremophor EL was performed. The obtained microemulsions were further characterized for their physicochemical properties. In addition, Fourier Transformed-Infrared spectroscopy was used touate the compatibility of active ingredients and components. In vitro release studies along with kinetic modeling were performed using the dialysis membrane method in simulated tear fluid. Bioadhesion studies were performed using Texture analysis. Finally, in vitro ocular irritation based on EpiOcular™ Eye Irritation Test and cytocompatibility studies was performed to examine any possible harm on ocular cells and predict in vivo safety profile.

The goal of this study was to develop and examine the nanogel-based topical delivery system of mupirocin. Nanogels were prepared with chitosan and bovine serum albumin by ionic gelation and Carbopol 940 was added to improve the gelling/adhesive properties. Detailed characterization studies were performed and the cellular binding capacity of radiolabeled nanogels was investigated on CCD-1070Sk cell lines. Results indicate the successful formation of nanogels with particle size and zeta potential ranged between 341.920-603.320 nm and 13.120-24.300 mV, respectively. The mechanical and rheological studies proved pseudoplastic and strong elastic gel behavior (G′ > G′′). Mupirocin was successfully entrapped into nanogels with a ratio of more than 95% and the loaded drug was slowly released up to 93.89 ± 3.07% within 24h. The ex vivo penetration and permeation percentages of mupirocin were very low (1.172 ± 0.202% and 0.161 ± 0.136%) indicating the suitability of nanogels for dermal use against superficial skin infections. The microbiological studies pointed out the effectiveness of nanogels against Staphylococcus aureus strains. Nanogels did not show toxicity signs and the cell binding capacity of radiolabeled formulations was found to be higher than [^99mTc]NaTcO₄ to CCD-1070Sk cell line. Overall, mupirocin nanogels might be considered as a potential and safe topical treatment option for bacterial skin infections. Graphical Abstract

Modern drug carrier technologies, such as microemulsions with small droplet sizes and high surface areas, improve the ability of low water solubility active ingredients to permeate and localize. The goal of this study was to create microemulsion formulations for wound healing that contained both fusidic acid (FA), an antibacterial agent, and benzocaine (BNZ), a local anesthetic. Studies on characterization were carried out, including viscosity, droplet size, and zeta potential. The drug-loaded microemulsion had a stable structure with –3.014 ± 1.265 mV of zeta potential and 19.388 ± 0.480 nm of droplet size. In both in vitro release and ex vivo permeability studies, the microemulsion was compared with Fucidin cream and oily BNZ solution. According to the drug release studies, BNZ release from the microemulsion and the BNZ solution showed a similar profile (p > 0.05), while FA release from the microemulsion had a higher drug release compared to Fucidin cream (p < 0.001). The microemulsion presented lower drug permeation (p > 0.05) for both active ingredients, on the other hand, provided higher drug accumulation compared to the control preparations. Moreover, according to the results of in vitro wound healing activity, the microemulsion indicated a dose-dependent wound healing potential with the highest wound healing activity at the highest concentrations. To the best of our knowledge, this developed BNZ- and FA-loaded microemulsion would be a promising candidate to create new opportunities for wound healing thanks to present the active ingredients, which have low water solubility, in a single formulation and achieved higher accumulation than control preparations. Graphical Abstract