Sherif E . Emam

Exosomes (EXOs) were given attention as an extracellular vesicle (EV) with a pivotal pathophysiological role in the development of certain neurodegenerative disorders (NDD), such as Parkinson’s and Alzheimer’s disease (AD). EXOs have shown the potential to carry pathological and therapeutic cargo; thus, researchers have harnessed EXOs in drug delivery applications. EXOs have shown low immunogenicity as natural drug delivery vehicles, thus ensuring efficient drug delivery without causing significant adverse reactions. Recently, EXOs provided potential drug delivery opportunities in AD and promising future clinical applications with the diagnosis of NDD and were studied for their usefulness in disease detection and prediction prior to the emergence of symptoms. In the future, the microfluidics technique will play an essential role in isolating and detecting EXOs to diagnose AD before the development of advanced symptoms. This review is not reiterative literature but will discuss why E...

ABSTRACT The low dissolution and limited solubility of sulpiride (SUL) resulted in a slow and incomplete absorption after oral administration with bioavailability not exceeding 30%. The aim of the present study was to improve the dissolution of SUL by solid dispersion (SD) technology using solvent evaporation technique. Different water soluble carriers namely tartaric acid, polyethylene glycol (PEG) 4000, polyvinylpyrrolidone (PVP) K30, and glucose were used. The prepared dispersions as well as the corresponding physical mixtures (PM) were evaluated for chemical and physical interactions by Fourier transform infrared (FTIR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The effect of changing the pH of the medium on drug solubility, SD’s drug potency and dissolution rate were studied. Moreover, the pharmacokinetics following the administration of either the raw drug or its tartaric acid SD into male rabbits were studied. SD showed improvement in SUL dissolution compared to the raw drug and PM, whereas SD prepared by tartaric acid showed the highest dissolution efficiency. FTIR, DSC and XRD diffraction revealed an interaction between SUL and the selected carriers, with possibility of a SUL polymorphic transition that resulted in an enhancement of its dissolution characteristics. Compared to the raw drug, higher Cmax and AUC values were obtained for its dispersion with tartaric acid with an increase in SUL bioavailability by about two folds. Hence, the proposed study offered a new solid state of SUL with an improved dissolution and in vivo performance for oral administration.

Pharmaceutical development was adopted in the current study to propose a pediatric rectal formulation of sulpiride as a substitute to the available oral or parenteral formulations in the management of Tourette syndrome (TS). The goal was to formulate a product that is easy to use, stable, and highly bioavailable and to achieve a rapid clinical efficacy. Towards this aim, sulpiride solid dispersion (SD) with tartaric acid at a weight ratio of 1:0.25 was incorporated into different suppository bases, namely witepsol W25, witepsol H15, witepsol E75, suppocire NA, suppocire A, glycerogelatin, and polyethylene glycols. The formulae were evaluated in vitro using different pharmacotechnical methods such as visual, melting, weight and content uniformities, drug release, differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), and X-ray diffraction (XRD) analyses. In vivo bioavailability was also assessed in rabbits to compare the bioavailability of either raw sulpiride-incorporated or its SD-incorporated witepsol H15-based suppositories to its oral suspension (reference). Sulpiride SD-incorporated witepsol H15 formulation showed acceptable in vitro characteristics with a bioavailability of 117% relative to oral dosing, which excel that in humans (27% after dosing of oral product). In addition, the proposed formula not only passed the 6-month stability study but also proposed a promising scale-up approach. Hence, it showed a great potential for pediatric product development to manage TS in rural areas.