Preparation and evaluation of etoposide-loaded lipid-based nanosuspensions for high-dose treatment of lymphoma

A liposomal etoposide with a sustained drug release effectively alleviated the therapy-related leukemia

Etoposide (VP16) can induce therapy-related leukemia, which is reported to occur less frequently with a prolonged dose schedule. Therefore, we hypothesized that nanocarriers could decrease the VP16-induced leukemogenesis by reducing the rate of VP16 exposure via a sustained drug release. To test our hypothesis, the VP16-loaded liposome with a slow drug release behavior was constructed by encapsulating a rapidly-cleaved VP16-maleimide conjugate into liposomes using a glutathione-gradient loading method, and its toxicities and in vivo antitumor efficacy were compared with free VP16 in the LLC lung cancer xenograft. It was found that the repeated injection of free VP16 induced severe splenomegaly, lymphocytosis, and extensive lymphocyte infiltration in various tissues, indicating a sign of VP16 therapy-related leukemia. By contrast, the liposomal VP16 not only remarkably alleviated the syndrome of leukemogenesis, but also exhibited significantly enhanced antitumor activity as compared with free VP16 at the same dose. These results highlighted that the liposomal VP16 having a sustained drug release could effectively decrease the toxicity of leukemogenesis, which provided a new warranty to develop liposomal VP16 as a safe alternative to the commercial VP16 injection.

Nanosuspensions technology as a master key for nature products drug delivery and In vivo fate

The drug nanosuspensions is a universal formulation approach for improved drug delivery of hydrophobic drugs and one the most promising approaches for increasing the biopharmaceutical performance of poorly water-soluble drug substances, especially for nature products. This review aimed to summarize the nanosuspensions preparation approaches and the main technological difficulties encountered in nanosuspensions development, such as guidelines for stabilizers screening, in vivo fate of the intravenously administrated nanosuspensions, and how to realize the intravenously target delivery was reviewed. Furthermore, challenges of nanosuspensions for the nature products delivery also was discussed and commented. Therefore, it hoped to provide reference and assistance for the nanosuspensions production, stabilizers usage, and predictability of in vivo fate and controllability of targeting delivery of the nature products nanosuspensions.

Biomedical Applications of Multifunctional Polymeric Nanocarriers: A Review of Current Literature

Polymeric nanomaterials have become a prominent area of research in the field of drug delivery. Their application in nanomedicine can improve bioavailability, pharmacokinetics, and, therefore, the effectiveness of various therapeutics or contrast agents. There are many studies for developing new polymeric nanocarriers; however, their clinical application is somewhat limited. In this review, we present new complex and multifunctional polymeric nanocarriers as promising and innovative diagnostic or therapeutic systems. Their multifunctionality, resulting from the unique chemical and biological properties of the polymers used, ensures better delivery, and a controlled, sequential release of many different therapeutics to the diseased tissue. We present a brief introduction of the classical formulation techniques and describe examples of multifunctional nanocarriers, whose biological assessment has been carried out at least in vitro. Most of them, however, also underwent evaluation in vivo on animal models. Selected polymeric nanocarriers were grouped depending on their medical application: anti-cancer drug nanocarriers, nanomaterials delivering compounds for cancer immunotherapy or regenerative medicine, components of vaccines nanomaterials used for topical application, and lifestyle diseases, ie, diabetes.

Synergistic Combination of Sodium Aescinate-Stabilized, Polymer-Free, Twin-Like Nanoparticles to Reverse Paclitaxel Resistance

BACKGROUND

The development of paclitaxel (PTX) resistance seriously restricts its clinical efficacy. An attractive option for combating resistance is inhibiting the expression of P-glycoprotein (P-gp) in tumor cells. We have reported that flavokawain A (FKA) inhibited P-gp protein expression in PTX-resistant A549 (A549/T) cells, indicating that FKA combined with PTX may reverse PTX resistance. However, due to the variable pharmacokinetics of FKA and PTX, the conventional cocktail combination in clinics may cause uncertainty of treatment efficacy in vivo.

MATERIALS AND METHODS

To synergistically elevate the anti-cancer activity of PTX and FKA in vivo, the national medical products administration (NMPA) approved sodium aescinate (Aes) was utilized to stabilize hydrophobic PTX and FKA to form polymer-free twin like PTX-A nanoparticles (NPs) and FKA-A NPs.

RESULTS

The resulting nanoparticles prepared simply by nanoprecipitation possessed similar particle size, good stability and ultrahigh drug loadings of up to 50%. With the aid of Aes, these two drugs accumulated in tumor tissue by passive targeting and were efficiently taken up by A549/T cells; this resulted in significant suppression of tumor growth in A549/T homograft mice at a low PTX dose (2.5 mg·kg-1). Synergistic effects and reversed PTX resistance were achieved by the combination of PTX-A NPs and FKA-A NPs by inhibiting P-gp expression in tumor cells.

CONCLUSION

Using NMPA-approved Aes to prepare twin-like nanoparticles without introducing any new materials provides an efficient platform for combination chemotherapy and clinical translation.

Tea saponins as natural stabilizers for the production of hesperidin nanosuspensions

Tea saponins (TS), a novel multifunctional stabilizer, were explored to stabilize the nanosuspensions. The purpose of this study was to investigate the effect of TS on the stability and redispersibility of nanosuspensions. In present work, hesperidin (HDN), a poorly soluble drug, was used as a model drug. HDN nanosuspensions (HDN-NS) with particle size of 250-270 nm were prepared by high-speed shearing and high-pressure homogenization. The zeta potential of HDN-NS was -23.16 ± 1.12 mV. Compared with traditional stabilizers, TS were superior in stabilization efficiency at low concentrations. Nanosuspensions freeze-dried powder using TS and lactose as cryoprotectants had good redispersibility, and the average particle size was 266.5 ± 9.0 nm after reconstitution. TS and lactose can effectively prevent the irreversible agglomeration of HDN-NS during freeze-drying. The dissolution was enhanced owing to particle size reduction. Transmission electron microscopy (TEM) and Scanning electron microscopy (SEM) results showed that HDN nanocrystals were irregularly lumpy. The chemical structure and crystal state of HDN had not significantly changed during production. In conclusion, TS have the potential to stabilize and disperse nanosuspensions and provide a promising strategy for the development of poorly soluble drugs.