Bioinspired PROTAC-induced macrophage fate determination alleviates atherosclerosis.

Atherosclerosis is a major cause of death and disability in cardiovascular disease. Atherosclerosis associated with lipid accumulation and chronic inflammation leads to plaques formation in arterial walls and luminal stenosis in carotid arteries. Current approaches such as surgery or treatment with statins encounter big challenges in curing atherosclerosis plaque. The infiltration of proinflammatory M1 macrophages plays an essential role in the occurrence and development of atherosclerosis plaque. A recent study shows that TRIM24, an E3 ubiquitin ligase of a Trim family protein, acts as a valve to inhibit the polarization of anti-inflammatory M2 macrophages, and elimination of TRIM24 opens an avenue to achieve the M2 polarization. Proteolysis-targeting chimera (PROTAC) technology has emerged as a novel tool for the selective degradation of targeting proteins. But the low bioavailability and cell specificity of PROTAC reagents hinder their applications in treating atherosclerosis plaque. In this study we constructed a type of bioinspired PROTAC by coating the PROTAC degrader (dTRIM24)-loaded PLGA nanoparticles with M2 macrophage membrane (MELT) for atherosclerosis treatment. MELT was characterized by morphology, size, and stability. MELT displayed enhanced specificity to M1 macrophages as well as acidic-responsive release of dTRIM24. After intravenous administration, MELT showed significantly improved accumulation in atherosclerotic plaque of high fat and high cholesterol diet-fed atherosclerotic (ApoE-/-) mice through binding to M1 macrophages and inducing effective and precise TRIM24 degradation, thus resulting in the polarization of M2 macrophages, which led to great reduction of plaque formation. These results suggest that MELT can be considered a potential therapeutic agent for targeting atherosclerotic plaque and alleviating atherosclerosis progression, providing an effective strategy for targeted atherosclerosis therapy.

The microneedles carrying cisplatin and IR820 to perform synergistic chemo-photodynamic therapy against breast cancer.

BACKGROUNDS: Surgical resection and adjunct chemotherapy or radio-therapy has been applied for the therapy of superficial malignant tumor in clinics. Whereas, there are still some problems limit its clinical use, such as severe pains and side effect. Thus, it is urgent need to develop effective, minimally invasive and low toxicity therapy stagey for superficial malignant tumor. Topical drug administration such as microneedle patches shows the advantages of reduced systemic toxicity and nimble application and, as a result, a great potential to treat superficial tumors. METHODS: In this study, microneedle (MN) patches were fabricated to deliver photosensitizer IR820 and chemotherapy agent cisplatin (CDDP) for synergistic chemo-photodynamic therapy against breast cancer. RESULTS: The MN could be completely inserted into the skin and the compounds carrying tips could be embedded within the target issue for locoregional cancer treatment. The photodynamic therapeutic effects can be precisely controlled and switched on and off on demand simply by adjusting laser. The used base material vinylpyrrolidone-vinyl acetate copolymer (PVPVA) is soluble in both ethanol and water, facilitating the load of both water-soluble and water-insoluble drugs. CONCLUSIONS: Thus, the developed MN patch offers an effective, user-friendly, controllable and low-toxicity option for patients requiring long-term and repeated cancer treatments.

[In vitro targeting effect of lactoferrin modified PEGylated liposomes for hepatoma cells].

A lactoferrin-containing PEGylated liposome system (Lf-PLS) was developed and tested in vitro as a hepatoma-targeting drug delivery system. PEGylated liposomes (PLS) were successfully prepared using the thin film hydration method with peglipid post insertion. Lf was covalently conjugated onto the carboxyl terminal of DSPE-PEG2000-COOH on liposomes. Coumarin-6 was used to trace Lf-PLS with fluorescence. The cellular uptake of this system was carried out in asialoglycoprotein receptor (ASGPR) positive HepG2 cells via confocal microscopy and flow cytometry. The Lf-PLS liposome was observed as spherical or oval vesicles with the particle size around 130 nm, zeta potential about -30 mV and encapsulation efficiency more than 80%. The confocal microscopy images and flow cytometry data demonstrated that Lf-PLS resulted in significantly higher cell association by ASGPR positive HepG2 cells compared to PLS. The association between Lf-PLS and cells were dependent on the concentration, time and temperature, which was inhibited by pre-incubation with excessive free Lf. The results suggest that Lf-PLS has a good targeting effect on HepG2 cells in vitro. The targeting mechanism may be related to the specific binding of Lf and ASGPR on HepG2 cells, which guides Lf-PLS to the cell surface to induce an active endocytosis process. All these results demonstrated that Lf-PLS might be a potential drug delivery system in targeting hepatocellular carcinoma, which deserves more research on its targeting ability, antitumor efficiency, and metabolism in vivo for treatment of hepatomacellular carcinoma.

The use of amphiphilic copolymer in the solid dispersion formulation of nimodipine to inhibit drug crystallization in the release media: Combining nano-drug delivery system with solid preparations.

Solid dispersion is a widely used method to improve the dissolution and oral bioavailability of water-insoluble drugs. However, due to the strong hydrophobicity, the drug crystallization in the release media after drug dissolution and the resulted decreased drug absorption retards the use of solid dispersions. It is widely known that the amphiphilic copolymer can encapsulate the hydrophobic compounds and help form stable nano-dispersions in water. Inspired by this, we tried to formulate the solid dispersion of nimodipine by using amphipathic copolymer as one of the carriers. Concerning the solid dispersions, there are many important points involved in these formulations, such as the miscibility between the drug and the carriers, the storage stability of solid dispersions, the dissolution enhancement and so on. In this study, a systemic method is proposed. In details, the supersaturation test and the glass transition temperature (Tg) measurement to predict the crystallization inhibition, the ratios of different components and the storage stability, the interactions among the components were investigated in detail by nuclear magnetic resonance (1H NMR) and isothermal titration calorimetry (ITC) and, the final dissolution and oral bioavailability enhancement. It was found that the amphiphilic copolymer used in the solid dispersion encouraged the formation the drug loading micelles in the release media and, finally, the problem of drug crystallization in the dissolution process was successfully solved.

[Optimization of ligustrazine phosphate thermosensitive gel formulation by central composite design-response surface methodology].

OBJECTIVE: To optimize the formulation of ligustrazine phosphate thermosensitive gel by the central composite design-response surface methodology (RSM plus CCD). METHODS: In the formulation design using RSM plus CCD, independent variables were the amounts of poloxamer 407 and poloxamer 188, and gel temperature was dependent variable. Multilinear and quadratic models were used to estimate the relationship between the dependent and the independent variables, select the optimal formulations and validate. RESULTS: The quantitative relationships between two factors and evaluation index were characterized, quadratic model had better prediction capability than multilinear model. CONCLUSION: Quadratic model is performed in the optimization of formulation due to the statistical confidence. The optimization of ligustrazine phosphate thermosensitive gel formulation can be achieved by the central composite design and response surface methodology.