Bioresponsive gingerol-loaded alginate-coated niosomal nanoparticles for targeting intracellular bacteria and cancer cells

Targeting and treating intracellular pathogen infections has been long-standing challenge, particularly in light of the escalating prevalence of antimicrobial resistance. Herein, an optimum formulation of alginate (AL)-coated niosome-based carriers for delivery of herbal extract Gingerol (Gin) was developed to treat intracellular pathogen infections and cancer cells. We used Gin-Nio@AL as a model drug to assess its efficacy against Gram-negative/positive bacteria and breast cancer cell lines. Our investigation affirmed its heightened antibacterial and anticancer properties. The antibacterial activity of Gin-Nio@AL against intracellular Staphylococcus aureus (S. aureus) and pseudomonas aeruginosa (P. aeruginosa) was also tested. In the current study, the niosome nanoparticles containing herbal extract Gingerol were optimized regarding lipid content and Surfactant per Cholesterol molar ratio. The developed formulation provided potential advantages, such as smooth globular surface morphology, small diameter (240.68 nm), pH-sensitive sustained release, and high entrapment efficiency (94.85 %). The release rate of Gin from AL-coated niosomes (Gin-Nio@AL) in physiological and acidic pH is lower than uncoated nanoparticles (Gin-Nio). Besides, the release rate of Gin from niosomal formulations increased in acidic pH. The Gin-Nio@AL demonstrated good antimicrobial activity against S. aureus and P. aeruginosa, and compared to Gin-Nio, the MIC values decreased to 7.82 ± 0.00 and 1.95 ± 0.00 μg/mL, respectively. In addition, the time-kill assay results showed that the developed formulation significantly reduced the number of bacteria in both strains compared to other tested groups. The microtiter data and scanning electron microscope micrography showed that Gin-Nio@AL has a more significant inhibitory effect on biofilm formation than Gin-Nio and Gin. The cell cytotoxicity evaluation showed that Gin-Nio@AL reduced the survival rate of MDA-MB-231 cancer cells to 52.4 % and 45.2 % after 48 h and 72 h, respectively. The elimination of intracellular pathogens was investigated through a breast cancer cell infection in an in vitro model. Gin-Nio@AL exhibited an enhanced and sustained intracellular antibacterial activity against pathogens-infected breast cancer cells compared to other tested formulations. Overall, Gin-Nio@AL enables the triggered release and targeting of intra-extra cellular bacteria and cancer cells and provides a novel and promising candidate for treating intracellular pathogen infections and cancer cells.

Encapsulation of Thymol in Gelatin Methacryloyl (GelMa)-Based Nanoniosome Enables Enhanced Antibiofilm Activity and Wound Healing

Non-healing wounds impose huge cost on patients, healthcare, and society, which are further fortified by biofilm formation and antimicrobial resistance (AMR) problems. Here, Thymol, an herbal antimicrobial agent, is utilized to combat AMR. For efficient delivery of Thymol gelatin methacryloyl (GelMa), a hydrophilic polymeric hydrogel with excellent biocompatibility combined with niosome was used to encapsulate Thymol. After optimization of the niosomal Thymol (Nio-Thymol) in the company of GelMa (Nio-Thymol@GelMa) to achieve maximum entrapment efficiency, minimum size, and low polydispersity index, the Thymol release peaked at 60% and 42% from Nio-Thymol@GelMa in medium with pH values of 6.5 and 7.4 after 72 h, respectively. Furthermore, Nio-Thymol@GelMa demonstrated higher antibacterial and anti-biofilm activity than Nio-Thymol and free Thymol against both Gram-negative and Gram-positive bacteria. Interestingly, compared with other obtained formulations, Nio-Thymol@GelMa also led to greater enhancement of migration of human dermal fibroblasts in vitro, and higher upregulation of the expression of certain growth factors such as FGF-1, and matrix metalloproteinases such as MMP-2 and MMP-13. These results suggest that Nio-Thymol@GelMa can represent a potential drug preparation for Thymol to enhance the wound healing process and antibacterial efficacy.

In vitro Development of Controlled-Release Nanoniosomes for Improved Delivery and Anticancer Activity of Letrozole for Breast Cancer Treatment

INTRODUCTION

Breast cancer is among the most prevalent mortal cancers in women worldwide. In the present study, an optimum formulation of letrozole, letrozole-loaded niosome, and empty niosome was developed, and the anticancer effect was assessed in in vitro MCF-7, MCF10A and MDA-MB-231 breast cancer cell lines.

MATERIALS AND METHODS

Various niosomal formulations of letrozole were fabricated through thin-film hydration method and characterized in terms of size, polydispersity index (PDI), morphology, entrapment efficiency (EE%), release kinetics, and stability. Optimized niosomal formulation of letrozole was achieved by response surface methodology (RSM). Antiproliferative activity and the mechanism were assessed by MTT assay, quantitative real-time PCR, and flow cytometry. Furthermore, cellular uptake of optimum formulation was evaluated by confocal electron microscopy.

RESULTS

The formulated letrozole had a spherical shape and showed a slow-release profile of the drug after 72 h. The size, PDI, and eEE% of nanoparticles showed higher stability at 4°C compared with 25°C. The drug release from niosomes was in accordance with Korsmeyer-Peppa's kinetic model. Confocal microscopy revealed the localization of drug-loaded niosomes in the cancer cells. MTT assay revealed that all samples exhibited dose-dependent cytotoxicity against breast cancer cells. The IC50 of mixed formulation of letrozole with letrozole-loaded niosome (L + L3) is the lowest value among all prepared formulations. L+L3 influenced the gene expression in the tested breast cancer cell lines by down-regulating the expression of Bcl 2 gene while up-regulating the expression of p53 and Bax genes. The flow cytometry results revealed that L + L3 enhanced the apoptosis rate in both MCF-7 and MDA-MB-231 cell lines compared with the letrozole (L), letrozole-loaded niosome (L3), and control sample.

CONCLUSION

Results indicated that niosomes could be a promising drug carrier for the delivery of letrozole to breast cancer cells.