Denatured protein stabilized drug nanoparticles: tunable drug state and penetration across the intestinal barrier

Fighting Epilepsy with Nanomedicines-Is This the Right Weapon?

Epilepsy is a chronic and complex condition and is one of the most common neurological diseases, affecting about 50 million people worldwide. Pharmacological therapy has been, and is likely to remain, the main treatment approach for this disease. Although a large number of new antiseizure drugs (ASDs) has been introduced into the market in the last few years, many patients suffer from uncontrolled seizures, demanding the development of more effective therapies. Nanomedicines have emerged as a promising approach to deliver drugs to the brain, potentiating their therapeutic index. Moreover, nanomedicine has applied the knowledge of nanoscience, not only in disease treatment but also in prevention and diagnosis. In the current review, the general features and therapeutic management of epilepsy will be addressed, as well as the main barriers to overcome to obtain better antiseizure therapies. Furthermore, the role of nanomedicines as a valuable tool to selectively deliver drugs will be discussed, considering the ability of nanocarriers to deal with the less favourable physical-chemical properties of some ASDs, enhance their brain penetration, reduce the adverse effects, and circumvent the concerning drug resistance.

Stiripentol Enteric Solid Dispersion-Loaded Effervescent Tablets: Enhanced Dissolution, Stability, and Absorption

Due to poor solubility and stability in acid conditions, the gastrointestinal administration of stiripentol (STP) is still a significant challenge. This study aimed to explore the applicability of effervescent tablets compressed from STP-loaded enteric solid dispersions to improve the solubility and stability of the insoluble and acid-labile drug. STP-loaded solid dispersions (STP-SDs) and the effervescent tablets (STP-SD-ETs) were prepared using solvent evaporation and dry granulation technology, respectively, and their formulations were optimized. Then, STP-SDs were characterized regarding solid state, in vitro release, stability, etc. Results showed that enteric amorphous STP-SDs were successfully prepared and significantly improved the solubility and stability of STP. Moreover, compared with STP suspensions, the bioavailability of STP-SD-ETs was as high as 138.71%. Concomitantly, STP-SD-ETs significantly increased the intestinal absorption rate of STP. Overall, the oral preparation encompassing enteric solid dispersion combined with effervescent tablet technology possesses excellent performance in enhancing dissolution, anti-acid hydrolysis stability, and absorption of STP. Our work provides a promising method to improve the delivery of drugs with poor solubility and acid-labile stability.

Deliver Anti-inflammatory Drug Baicalein to Macrophages by Using a Crystallization Strategy

Macrophages are potent to modulate inflammation via phenotypic switch and production of inflammatory factors. Baicalein (BCL) is frequently used to alleviate inflammation; however, its application is always hindered due to low solubility. Herein, BCL nanocrystals (BNRs) were prepared to improve its delivery to macrophages. The prepared BNRs have a diameter of 150 nm with a rod-like structure. The nanocrystals could be well-taken up by macrophages via the caveolar pathway and, therefore, promote the polarization switch from proinflammatory phenotype to anti-inflammatory macrophages and alleviate the inflammation via reducing production cytokine IL-12. In conclusion, the crystallization strategy is promising for the improvement of the solubility of BCL and promotion of its anti-inflammatory activities.

Globular protein stabilized nanoparticles for delivery of disulfiram: fabrication, characterization, in vitro toxicity, and cellular uptake

Disulfiram (DSF), an FDA-approved anti-alcoholic drug, has recently shown that it possesses anti-cancer effects. However, DSF is hydrophobic in nature with less stability. Therefore, new approaches are required for the effective delivery of DSF to treat cancers. Herein, we prepared DSF loaded soy protein isolate (SPI) nanosuspension (Ns) for enhancing the anti-cancer delivery of DSF. The optimized DSF-SPI-Ns had an average particle size of 164.28 ± 2.07 nm with a narrow size distribution of 0.217 ± 0.035 and zeta potential around −22.30 ± 2.11 mV, respectively. The highest drug loading and entrapment efficiency achieved was 5.516 ± 1.98%, and 91.61 ± 1.15%, respectively. The surface morphology of Ns was revealed by TEM, and the FTIR DSC, PXRD, and TGA were used for physicochemical characterization. Further, fluorescence spectroscopy and molecular docking studies were carried out to understand the interactions between (SPI and DSF) and binding sites of DSF on the surface of SPI, respectively. In vitro release studies showed a sustained release pattern and followed a Fickian diffusion release from the Ns. The in vitro cytotoxicity of SPI indicated the excellent biocompatibility, and DSF-SPI-Ns were found to be more cytotoxic compared to the free DSF solution. Moreover, the cellular uptake studies also indicated the effective delivery of the formulation to the cancer cells. Results of the current study suggested that the SPI coated Ns might be a promising drug delivery system for hydrophobic DSF, and the potential application of SPI as a coating/stabilizing agent for the delivery of hydrophobic/hydrophilic cancer therapeutics.

Disulfiram (DSF), an FDA-approved anti-alcoholic drug, has recently shown that it possesses anti-cancer effects.

Fabrication of gold-silver core-shell nanoparticles for performing as ultrabright SERS-nanotags inside human ovarian cancer cells

This paper presents the fabrication and characterization of new gold-silver core-shell nanoparticles labeled with para-mercaptobenzoic acid (4MBA) molecules and demonstrates their use as surface-enhanced Raman spectroscopy (SERS)-nanotags with ultra-bright traceability inside cells and ability to convey spectrally-coded information about the intracellular pH by means of SERS. Unlike previous reported studies, our fabrication procedure includes in the first step the synthesis of chitosan-coated gold nanoparticles as a seed material with subsequent growing of a silver shell. The bimetallic core-shell structure is revealed by transmission electron microscopy, high-angle annular dark field scanning transmission electron microscopy, energy-dispersive x-ray elemental mapping and the presence of two interacting localized surface plasmon resonance modes in UV-vis extinction spectrum. The high SERS activity and sensitivity of as fabricated 4MBA-chit-Au-AgNPs nano-constructs to different pH in solution is investigated under 532 and 633 nm laser lines excitation. Next, in view of future studies in cancer diagnosis, the in vitro antiproliferative effects of SERS-nanotags against human ovarian adenocarcinoma cells (NIH:OVCAR-3) are evaluated. The capacity to operate as bright SERS nanotags with precise localization at a single cell level as well as intracellular pH indicators is clearly demonstrated by performing cell imaging under scanning confocal Raman microscopy.

Amorphous Nanosuspensions Aggregated from Paclitaxel⁻Hemoglobulin Complexes with Enhanced Cytotoxicity

Amorphous nanosuspensions (ANSs) enable rapid release and improved delivery of a poorly water-soluble drug; however, their preparation is challenging. Here, using hemoglobin (Hb) as a carrier, ANSs aggregated from paclitaxel (PTX)⁻Hb complexes were prepared to improve delivery of the hydrophobic anti-cancer agent. An affinity study demonstrated strong interaction between Hb and PTX. Importantly, the complexes could aggregate into <300 nm ANSs with high drug loading, which acidic condition facilitated their formation. Furthermore, the ANSs possessed improved cytotoxicity against cancer cells over the crystalline nanosuspensions. Taken together, ANSs aggregated from PTX⁻Hb complexes were developed, which could kill cancer cells with high efficiency.

A drug-delivering-drug strategy for combined treatment of metastatic breast cancer

Treatment of metastatic cancer continues to be a huge challenge worldwide. Notably, drug nanocrystals (Ns) in nanosuspensions clearly belong to a type of nanoparticle. Therefore, a question arose as to whether these drug particles can also be applied as carriers for drug delivery. Here, we design a novel paclitaxel (PTX) nanocrystal stabilized with complexes of matrix metalloproteinase (MMP)-sensitive β-casein/marimastat (MATT) for co-delivering MATT and PTX and combined therapy of metastatic breast cancer. The prepared Ns (200 nm) with a drug-loading of >50% were potent in treatment of metastatic cancer, which markedly inhibited MMP expression and activity and greatly blocked the lung metastasis and angiogenesis. In conclusion, employing protein-drug complexes as stabilizers, Ns with dual payloads are developed and are a promising strategy for co-delivery. Furthermore, the developed Ns can target the tumor microenvironment and cancer cells and, as a result, enable efficient treatment for breast metastatic cancer.

A Smart Paclitaxel-Disulfiram Nanococrystals for Efficient MDR Reversal and Enhanced Apoptosis

PURPOSE

A multidrug resistance (MDR) modulator, disulfiram (DSF), was incorporated into pure paclitaxel (PTX) nanoparticles to construct a smart paclitaxel-disulfiram nanococrystals (PTX-DSF Ns) stabilized by β-lactoglobulin (β-LG), with the aim to reverse MDR and therefore enhnce cytotoxicity towards Taxol-resistant A549 cells (A549/TAX).

METHOD

PTX-DSF Ns was prepared by antisolvent precipitation method. Flow cytometry was used to determine the cell uptake, drug efflux inhibition, cell cycle phase arrest and apoptosis. MDR-1 gene expression level was detected by real time quantitative PCR and gel electrophoresis.

RESULTS

PTX-DSF Ns prepared from the optimized formulation had an optimum diameter of 160 nm, was stable and had a high drug-loading capacity. Importantly, the uptake of PTX-DSF Ns in A549/TAX cells was 14-fold greater than the uptake of PTX Ns. Furthermore, PTX-DSF Ns promoted 5-folds increase in apoptosis, enabled 7-folds reduction in the IC₅₀, and rendered 8.9-fold decrease in the dose compared with free PTX.

CONCLUSION

PTX-DSF Ns with a precise mass ratio offer efficient cytotoxicity against Taxol-resistant cells and a novel approach for codelivery and sensitizing MDR cancer to chemotherapy. In addition, the use of nanosuspensions as a combined treatment provides a new research avenue for nanosuspensions.

Nanosuspensions of a new compound, ER-β005, for enhanced oral bioavailability and improved analgesic efficacy

Estrogen receptor-β005 (ER-β005) is a novel compound developed by our group; however, its application has been greatly hindered due to its low solubility. A nanosuspension of insoluble drugs is a nanoscale colloidal dispersion that has extremely higher drug-loading compared with other nanomedicines. In this study, nanosuspensions of ER-β005 (Nano-ER-β005) stabilized by a food protein, β-casein (β-CN), were prepared via an antisolvent-precipitation method to improve oral absorption and thus promote therapeutic efficacy. Nano-ER-β005, which has a diameter of 110nm and drug-loading of 50%, was developed. Analyses of fluorescence and circular dichroism (CD) spectra demonstrated a strong interaction between β-CN and drug particles in Nano-ER-β005, indicating that β-CN is a potent nanosuspension stabilizer. The oral bioavailability of Nano-ER-β005 was 1.6-fold greater than that of raw drug particles. Additionally, ER-β005 was confirmed to have a strong therapeutic effect against pain reactions in animal models, and inhibition of this effect was significantly increased with Nano-ER-β005 treatment. In conclusion, by using β-CN as a stabilizer, nanosuspensions of ER-β005 were developed and oral absorption was enhanced. Moreover, ER-β005 is a powerful drug that inhibits pain reactions, and its therapeutic efficacy was markedly increased in the Nano-ER-β005.