Synthesis and Characterization of Acylated Polycaprolactone (PCL) Nanospheres and Investigation of Their Influence on Aggregation of Amyloid Proteins

Facile synthesis and nanoscale features of a nanostructured nordihydroguaiaretic acid analog for therapeutic applications

BACKGROUND

Nordihydroguaiaretic acid (NDGA) is a plant lignan obtained from creosote bush, known to possess anti-oxidant, anti-cancer and anti-viral activities and is being used in traditional medicine. However, toxicity studies indicated liver and kidney damage despite its immense medicinal properties. There has been a recent increase of curiosity in the chemical synthesis of NDGA derivatives for therapeutic applications. NDGA derivatives have been developed as better alternatives to NDGA and for targeted delivery to the site of tissue by chemical derivatives. In this regard, an analog of NDGA, Acetyl NDGA (Ac-NDGA), has been synthesized based on a previous procedure and formulated as a nanostructured complex with Polycaprolactone/Polyethylene glycol polymer matrices, by o/w solvent evaporation method.

RESULTS

The drug-incorporated polymeric nanospheres exhibited a drug load of 10.0 ± 0.5 µg drug per mg of nanospheres in acetonitrile solvent with 49.95 ± 10% encapsulation efficiency and 33-41% drug loading capacity with different batches of nanospheres preparation. The in vitro drug release characteristics indicated 82 ± 0.25% drug release at 6 h in methanol. Further, the nanospheres have been characterized extensively to evaluate their suitability for therapeutic delivery.

CONCLUSIONS

The present studies indicate a new and efficient formulation of the nanostructured AcNDGA with good therapeutic potential.

Preparation and characterization of curcumin-loaded polymeric nanomicelles to interference with amyloidogenesis through glycation method

Amyloid fibrils, including β-amyloid (Aβ) fibrils, are protein aggregates that form under certain conditions, associated with neurodegeneration that interfere with neural synaptic transmission resulting in some neural disorders, such as Alzheimer's disease. The aim of this study is to inhibit amyloidogenesis by using preparatory polymeric nanomicelles as therapeutic agents and also as nanocarriers for curcumin to target Aβ fibrils through the glycation method of bovine serum albumin (BSA) in the presence of phosphate-buffered saline. Polymeric nanomicelles were prepared from phosphatidylethanolamine-distearoyl methoxypolyethylene glycol conjugates in the presence and absence of curcumin and then the morphological and structural characteristics of the nanomicelles were characterized in detail. Following the preparation of unloaded and curcumin-loaded nanomicelles with the desired size and properties, their effects on BSA glycation/fibrillation process were investigated. The samples were analyzed by thioflavin T (ThT) fluorescence and advanced glycation end (AGE) products autofluorescence measurements. The results showed that ThT fluorescence related to the formation of β-sheets and AGE autofluorescence (associated with AGE production) decreased in the presence of curcumin-loaded nanomicelles more than other samples. In conclusion, the promising effect of curcumin-loaded nanomicelles on inhibition of amyloidogenesis through glycation process due to curcumin release and thus their ability to prevent the formation and accumulation of amyloid fibrils and so to suppress the Alzheimer's disease progression has been proven and can go for further investigations.

Multifunctional REDV-conjugated zwitterionic polycarboxybetaine–polycaprolactone hybrid surfaces for enhanced antibacterial activity, anti-thrombogenicity and endothelial cell proliferation

Multifunctional PCL hybrid surfaces are developed by grafting of REDV–zwitterionic polycarboxybetaine conjugates via surface-initiated ATRP.