Silk peptide-hyaluronic acid based nanogels for the enhancement of the topical administration of curcumin.

The present study focused on the development of Cur-loaded SOHA nanogels (Cur-SHNGs) to enhance the topical administration of Cur. The physiochemical properties of Cur-SHNGs were characterized. Results showed that the morphology of the Cur-SHNGs was spherical, the average size was 171.37 nm with a zeta potential of -13.23 mV. Skin permeation experiments were carried out using the diffusion cell systems. It was found that the skin retention of Cur-SHNGs was significantly improved since it showed the best retention value (0.66 ± 0.17 µg/cm2). In addition, the hematoxylin and eosin staining showed that the Cur-SHNGs improved transdermal drug delivery by altering the skin microstructure. Fluorescence imaging indicated that Cur-SHNGs could effectively deliver the drug to the deeper layers of the skin. Additionally, Cur-SHNGs showed significant analgesic and anti-inflammatory activity with no skin irritation. Taken together, Cur-SHNGs could be effectively used for the topical delivery of therapeutic drugs.

Berberine-Loaded Thiolated Pluronic F127 Polymeric Micelles for Improving Skin Permeation and Retention.

BACKGROUND: Challenges associated with local antibacterial and anti-inflammatory drugs include low penetration and retention of drugs at the expected action site. Additionally, improving these challenges allows for the prevention of side effects that are caused by drug absorption into the systemic circulation and helps to safely treat local skin diseases. METHODS: In the current study, we successfully prepared a thiolated pluronic F127 polymer micelles (BTFM), which binds to keratin through a disulphide bond, to produce skin retention. In addition, the small particle size of polymer micelles promotes the penetration of carriers into the skin. The current study was divided into two experiments: an in vitro experiment; an in vivo experiment that involved the penetration of the micelle-loaded drugs into the skin of rats, the skin irritation test and the anti-inflammatory activity of the drug-loaded micelles on dimethyl benzene-induced ear edema in mice. RESULTS: Results from our in vitro transdermal experiment revealed that the amount of drug absorbed through the skin was decreased after the drug was loaded in the BTFM. Further, results from the vivo study, which used fluorescence microscopy to identify the location of the BTFM after penetration, revealed that there was strong fluorescence in the epidermis layer, but there was no strong fluorescence in the deep skin layer. In addition, the BTFM had a very good safety profile with no potentially hazardous skin irritation and transdermal administration of BTFM could significantly suppress ear edema induced by dimethyl benzene. Therefore, these findings indicated that BTFM reduced the amount of drug that entered the systemic circulation. Our results also demonstrated that the BTFM had a certain affinity for keratin. CONCLUSION: Our experimental results suggest that the BTFM may be an effective drug carrier for local skin therapy with good safety profile.

A novel long-sustaining system of apatinib for long-term inhibition of the proliferation of hepatocellular carcinoma cells.

Background: Apatinib is a newly approved antitumor drug (molecular targeted agent/small molecular kinase inhibitor) for advanced hepatocellular carcinoma (HCC) treatment. However, current oral administration of apatinib could induce the even distribution of drugs in the body and cause the concentration of apatinib in the HCC location to be limited or insufficient. Therefore, it is urgent to develop novel formulations of apatinib to improve its efficiency. Materials and methods: Apatinib was prepared to form a stable and even dispersion with cyclodextrin (a clathrate complex/inclusion complex named Apa-Cyc). A temperature-sensitive phase-change hydrogel of apatinib (named Apa-Gel) was prepared using apatinib-cyclodextrin and poloxamer 407. Apa-Gel was injected into HCC tissues in nude mice to examine the long-term antitumor effect. Results: Apa-Gel can transform from liquid to hydrogel at near body temperature and maintain slow release of apatinib in HCC tumor tissues. When injected subcutaneously, one-time administration of Apa-Gel has a long-acting antitumor effect on the subcutaneous growth or epithelial-mesenchymal transition process of HCC cells. Conclusion: This novel slow-releasing system allows apatinib to be released effectively on the long term and facilitates tissue attachment, thereby preserving the efficiency of apatinib over the long term.