The Effects of Cetirizine on P-glycoprotein Expression and Function In vitro and In situ

Perspectives on drug repurposing to overcome cancer multidrug resistance mediated by ABCB1 and ABCG2

The overexpression of the human ATP-binding cassette (ABC) transporters in cancer cells is a common mechanism involved in developing multidrug resistance (MDR). Unfortunately, there are currently no approved drugs specifically designed to treat multidrug-resistant cancers, making MDR a significant obstacle to successful chemotherapy. Despite over two decades of research, developing transporter-specific inhibitors for clinical use has proven to be a challenging endeavor. As an alternative approach, drug repurposing has gained traction as a more practical method to discover clinically effective modulators of drug transporters. This involves exploring new indications for already-approved drugs, bypassing the lengthy process of developing novel synthetic inhibitors. In this context, we will discuss the mechanisms of ABC drug transporters ABCB1 and ABCG2, their roles in cancer MDR, and the inhibitors that have been evaluated for their potential to reverse MDR mediated by these drug transporters. Our focus will be on providing an up-to-date report on approved drugs tested for their inhibitory activities against these drug efflux pumps. Lastly, we will explore the challenges and prospects of repurposing already approved medications for clinical use to overcome chemoresistance in patients with high tumor expression of ABCB1 and/or ABCG2.

Zinc Oxide–Graphene Nanocomposite-Based Sensor for the Electrochemical Determination of Cetirizine

A nanocomposite electrode of graphene (Gr) and zinc oxide (ZnO) nanoparticles was fabricated to study the electrochemical oxidation behavior of an anti-inflammatory drug, i.e., cetirizine (CET). The voltametric response of CET for bare CPE, Gr/CPE, ZnO/CPE, and the ZnO-Gr nanocomposite electrode was studied. The modifier materials were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray powder diffraction (XRD) to comprehend the surface morphology of the utilized modifiers. The influence of pH, scan rate, and accumulation time on the electrooxidation of CET was examined. It was found that the electrochemical oxidation of CET was diffusion-controlled, in which two protons and two electrons participated. The detection limit was found to be 2.8 × 10−8 M in a linearity range of 0.05–4.0 µM. Study of excipients was also performed, and it was found that they had negligible interference with the peak potential of CET. The validation and utility of the fabricated nanocomposite sensor material were examined by analyzing clinical and biological samples. Stability testing of the nanocomposite electrode was conducted to assess the reproducibility, determining that the developed biosensor has good stability and high efficiency in producing reproducible results.

Optimization, in vitro release and toxicity evaluation of novel pH sensitive itaconic acid-g-poly(acrylamide)/sterculia gum semi-interpenetrating networks

BACKGROUND

In recent era, pH sensitive polymeric carriers that combines the materials engineering and medicine is gaining researcher's attention as they maximizes drug concentration at site of absorption and reduces side effects for e.g. orally administered cetirizine HCl (CTZ HCl) upsets the stomach and furthermore shows high intestinal absorption. Thus, development of pH sensitive hydrogels with sufficient mechanical strength will be good candidate to address this issue.

METHODS

Here, we developed pH sensitive itaconic acid-g-poly(acrylamide)/sterculia gum (IA-g-poly(AM)/sterculia gum) semi-interpenetrating network (semi-IPN) by free radical polymerization technique for intestinal delivery of CTZ HCL.

RESULTS

Optimized formulation (I5) with 6% w/w IA showed negligible swelling at pH 1.2, and maximum swelling at pH 7.4. Solid state characterization of optimized formulation showed successful development of semi-IPN structure and incorporation of drug without any noticeable drug-carrier interaction. In vitro release study showed biphasic pH dependent release of CTZ HCl, where initial burst release was observed at acidic pH followed by sustained release at basic pH. Acute oral toxicity and histopathological studies confirmed the non-toxic nature of IA-g-poly(AM)/sterculia gum.

CONCLUSION

Conclusively, developed biocompatible semi-IPN hydrogels with sufficient pH sensitivity and mechanical strength could serve as a potential carrier for intestinal delivery of CTZ HCL to maximize its absorption and reduce side effects.

ABCB1 in dermatology: roles in skin diseases and their treatment

Adenosine triphosphate-binding cassette subfamily B member 1 (ABCB1), also known as permeability glycoprotein, multidrug-resistant protein 1, or cluster of differentiation 243 (CD243), is a crucial protein for purging foreign substances from cells. The functions of ABCB1 have been investigated extensively for their roles in cancer, stem cells, and drug resistance. Abundant pharmacogenetic studies have been conducted on ABCB1 and its association with treatment responsiveness to various agents, particularly chemotherapeutic and immunomodulatory agents. However, its functions in the skin and implications on dermatotherapeutics are far less reported. In this article, we reviewed the roles of ABCB1 in dermatology. ABCB1 is expressed in the skin and its appendages during drug delivery and transport. It is associated with treatment responsiveness to various agents, including topical steroids, methotrexate, cyclosporine, azathioprine, antihistamines, antifungal agents, colchicine, tacrolimus, ivermectin, tetracycline, retinoid acids, and biologic agents. Moreover, genetic variation in ABCB1 is associated with the pathogenesis of several dermatoses, including psoriasis, atopic dermatitis, melanoma, bullous pemphigoid, Behçet disease, and lichen planus. Further investigation is warranted to elucidate the roles of ABCB1 in dermatology and the possibility of enhancing therapeutic efficacy through ABCB1 manipulation.

Cyclodextrin-based nanosponges as promising carriers for active agents

INTRODUCTION

In recent years, new drug delivery systems have attempted to overcome the undesirable pharmacokinetic problems of various drugs. Among them, cyclodextrin nanosponges (CDNSs) attract great attention from researchers for solving major bioavailability problems such as inadequate solubility, poor dissolution rate, and the limited stability of some agents, as well as increasing their effectiveness and decreasing unwanted side effects. This novel system can also be prepared as different dosage forms.

AREAS COVERED

This review will give an insight into the effects of CDNSs on the pharmacokinetic parameters and permeability of active agents. Different classes of drugs delivered by this system are mentioned and we designate which CD is used most widely in their production process. We also inform why this carrier can be introduced as a versatile carrying system in pharmaceutical fields. Registered patents about this novel system in various fields are also mentioned.

EXPERT OPINION

The readers will be informed on CDNSs as a novel carrier especially for the delivery of drugs. Versatile characteristics and applications of them can also be known by this review. Finally, CDNSs may be introduced as a remarkable vehicle in the pharmaceutical market in coming years.

Image-based QSAR Model for the Prediction of P-gp Inhibitory Activity of Epigallocatechin and Gallocatechin Derivatives

BACKGROUND

Permeability glycoprotein (P-gp) is one of the cell membrane proteins that can push some drugs out of the cell causing drug tolerance and its inhibition can prevent drug resistance.

OBJECTIVE

In this study, we used image-based Quantitative Structure-Activity Relationship (QSAR) models to predict the P-gp inhibitory activity of epigallocatechin and gallocatechin derivatives.

METHODS

The 2D-chemical structures and their P-gp inhibitory activity were taken from literature. The pixels of images and their Principal Components (PCs) were calculated using MATLAB software. Principle Component Regression (PCR), Artificial Neural Network (ANN) and Support Vector Machine (SVM) approaches were used to develop QSAR models. Statistical parameters included the leave one out cross-validated correlation coefficient (q2) for internal validation of the models and R2 of test set, Root Mean Square Error (RMSE) and Concordance Correlation Coefficient (CCC) were applied for external validation.

RESULTS

Six PCs from image analysis method were selected by stepwise regression for developing linear and non-linear models. Non-linear models i.e. ANN (with the R2 of 0.80 for test set) were chosen as the best for the established QSAR models.

CONCLUSION

According to the result of the external validation, ANN model based on image analysis method can predict the P-gp inhibitory activity of epigallocatechin and gallocatechin derivatives better than the PCR and SVM models.

Inhibition of P-Glycoprotein Mediated Efflux in Caco-2 Cells by Phytic Acid

Phytic acid (IP6) is a natural phosphorylated inositol, which is abundantly present in most cereal grains and seeds. This study investigated the effects of IP6 regulation on P-glycoprotein (P-gp) and its potential mechanisms using in situ and in vitro models. The effective permeability of the typical P-gp substrate rhodamine 123 (R123) in colon was significantly increased from (1.69 ± 0.22) × 10^-5 cm/s in the control group to (3.39 ± 0.417) × 10^-5 cm/s (p < 0.01) in the 3.5 mM IP6 group. Additionally, IP6 can concentration-dependently decrease the R123 efflux ratio in both Caco-2 and MDCK II-MDR1 cell monolayers and increase intracellular R123 accumulation in Caco-2 cells. Furthermore, IP6 noncompetitively inhibited P-gp by impacting R123 efflux kinetics. The noncompetitive inhibition of P-gp by IP6 was likely due to decreases in P-gp ATPase activity and P-gp molecular conformational changes induced by IP6. In summary, IP6 is a promising P-gp inhibitor candidate.

Identification of drug transporters involved in the uptake and efflux of rhein in hepatocytes

Rhein is an herbal medicine with various bioactivities and is derived from an anthraquinone compound. In this study, we aimed to identify drug transporters involved in the uptake and efflux of rhein in hepatocytes.