The insulin long-acting chitosan - Polyethyleneimine nanoparticles to treat the type 2 diabetes mellitus and prevent the associated complications.

Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder, which is ultimately treated by the insulin (INS). However, the subcutaneous (s. c.) injection of insulin solution faces the problems of pain and unsatisfactory patient compliance. In this study, the long-acting formulations of insulin are propsed to treat the T2DM and prevent the associated complications. The chitosan (CS) and/or branched polyethyleneimine (bPEI) nanoparticles (bPEI-INS NPs, CS-bPEI-INS NPs) were constructed to load insulin. The long -acting nanoparticles successfully achieved the sustained release of the INS in vitro and in vivo. After s. c. administration, the CS-bPEI-INS NPs greatly improved the INS bioavailability. As a result, the CS-bPEI-INS NPs produced sustained glucose-lowering effects, promising short-term and long-term hypoglycemic efficacy in the T2DM model. Furthermore, the treatment of the CS-bPEI-INS NPs greatly protected the islet in the pancreas and prevented the associated complications of the T2DM, such as cardiac fibrosis in the myocardial interstitium and the perivascular area. In a word, the CS-bPEI-INS NPs was an encouraging long-acting formulation of insulin and had great potential in the treatment of T2DM.

The Antibacterial Effects of Supermolecular Nano-Carriers by Combination of Silver and Photodynamic Therapy.

The over-use of antibiotics has promoted multidrug resistance and decreased the efficacy of antibiotic therapy. Thus, it is still in great need to develop efficient treatment strategies to combat the bacteria infection. The antimicrobial photodynamic therapy (aPDT) and silver nanoparticles have been emerged as effective antibacterial methods. However, the silver therapy may induce serious damages to human cells at high concentrations and, the bare silver nanoparticles may rapidly aggregate, which would reduce the antibacterial efficacy. The encapsulation of sliver by nano-carrier is a promising way to avoid its aggregation and facilitates the co-delivery of drugs for combination therapy, which does not require high concentration of sliver to exert antibacterial efficacy. This work constructed a self-assembled supermolecular nano-carrier consisting of the photosensitizers (PSs), the anti-inflammatory agent and silver. The synthesized supermolecular nano-carrier produced reactive oxygen species (ROS) under the exposure of 620-nm laser. It exhibited satisfying biocompatibility in L02 cells. And, this nano-carrier showed excellent antibacterial efficacy in Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) as indicated by bacterial growth and colony formation. Its antibacterial performance is further validated by the bacteria morphology through the scanning electron microscope (SEM), showing severely damaged structures of bacteria. To summary, the supermolecular nano-carrier TCPP-MTX-Ag-NP combining the therapeutic effects of ROS and silver may serve as a novel strategy of treatment for bacterial infection.

Doxorubicin-loaded hydrogen peroxide self-providing copper nanodots for combination of chemotherapy and acid-induced chemodynamic therapy against breast cancer.

In recent years, chemodynamic therapy (CDT) has gained increasing interest in cancer treatment. In contrast to photodynamic therapy and sonodynamic therapy, extrinsic excitations such as laser or ultrasound are not required in CDT. As a result, the CDT performance is not limited by the penetration depth of the external irritation. However, CDT relies heavily on hydrogen peroxide (H2O2) in the tumour microenvironment (TME). Insufficient H2O2 in the TME limits the CDT performance, and the most reported methods to produce H2O2 in the TME are dependent on oxygen supply, which is restricted by the hypoxic TME. In this study, H2O2 self-providing copper nanodots were proposed, and the drug doxorubicin (DOX) was successfully loaded to construct DOX-nanodots. Our results showed that the nanodots produced H2O2 in the weakly acidic TME due to the peroxo group and further generated the most active hydroxyl radical (OH) through the Fenton-like reaction. This process was pH-dependent and did not occur in a neutral environment. In addition to OH, the nanodots also produced singlet oxygen (1O2) and superoxide anions (O2-) in the cancer cells. The copper nanodots performed promising CDT against breast cancer in vitro and in vivo, with enhanced cell apoptosis and decreased cell proliferation. The combination of chemotherapy and CDT using DOX-nanodots further improved the therapeutic effects. The treatments showed good biocompatibility with no obvious toxicity in major tissues, possibly due to the specific OH generation in the weakly acidic TME. In summary, the H2O2 self-providing copper nanodots in combination with DOX showed promising cancer-curing effects due to the oxygen-independent and tumour-specific production of reactive oxygen species and the cooperation of chemotherapy.

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.

Bismuth chelate as a contrast agent for X-ray computed tomography.

BACKGROUNDS: Due to the unexpected side effects of the iodinated contrast agents, novel contrast agents for X-ray computed tomography (CT) imaging are urgently needed. Nanoparticles made by heavy metal elements are often employed, such as gold and bismuth. These nanoparticles have the advantages of long in vivo circulation time and tumor targeted ability. However, due to the long residence time in vivo, these nanoparticles may bring unexpected toxicity and, the preparation methods of these nanoparticles are complicated and time-consuming. METHODS: In this investigation, a small molecular bismuth chelate using diethylenetriaminepentaacetic acid (DPTA) as the chelating agent was proposed to be an ideal CT contrast agent. RESULTS: The preparation method is easy and cost-effective. Moreover, the bismuth agent show better CT imaging for kidney than iohexol in the aspect of improved CT values. Up to 500 µM, the bismuth agent show negligible toxicity to L02 cells and negligible hemolysis. And, the bismuth agent did not induce detectable morphology changes to the main organs of the mice after intravenously repeated administration at a high dose of 250 mg/kg. The pharmacokinetics of the bismuth agent follows the first-order elimination kinetics and, it has a short half-life time of 0.602 h. The rapid clearance from the body promised its excellent biocompatibility. CONCLUSIONS: This bismuth agent may serve as a potential candidate for developing novel contrast agent for CT imaging in clinical applications.

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.

Preparation, characterization and in vitro-in vivo evaluation of bortezomib supermolecular aggregation nanovehicles.

BACKGROUNDS: Intolerable toxicity and unsatisfactory therapeutic effects are still big problems retarding the use of chemotherapy against cancer. Nano-drug delivery system promised a lot in increasing the patients' compliance and therapeutic efficacy. As a unique nano-carrier, supermolecular aggregation nanovehicle has attracted increasing interests due to the following advantages: announcing drug loading efficacy, pronouncing in vivo performance and simplified production process. METHODS: In this study, the supermolecular aggregation nanovehicle of bortezomib (BTZ) was prepared to treat breast cancer. RESULTS: Although many supermolecular nanovehicles are inclined to disintegrate due to the weak intermolecular interactions among the components, the BTZ supermolecules are satisfying stable. To shed light on the reasons behind this, the forces driving the formation of the nanovehicles were detailed investigated. In other words, the interactions among BTZ and other two components were studied to characterize the nanovehicles and ensure its stability. CONCLUSIONS: Due to the promising tumor targeting ability of the BTZ nanovehicles, the supermolecule displayed promising tumor curing effects and negligible systemic toxicity.

Injectable hydrogel encapsulating Cu2MnS2 nanoplates for photothermal therapy against breast cancer.

BACKGROUND: In order to explore the possibility of treating breast cancer by local photo-therapy, a photothermal agents loaded in situ hydrogel was established. In detail, The Cu2MnS2 nanoplates were prepared by one-pot synthesis and, the thermosensitive Pluronic F127 was used as the hydrogel matrix. The Cu2MnS2 nanoplates and the hydrogel were characterized by morphous, particle size, serum stability, photothermal performance upon repeated 808 nm laser irradiation as well as the rheology features. The therapeutic effects of the Cu2MnS2 nanoplates and the hydrogel were evaluated qualitatively and quantitatively in 4T1 mouse breast cancer cells. The retention, photothermal efficacy, therapeutic effects and systemic toxicity of the hydrogel were assessed in tumor bearing mouse model. RESULTS: The Cu2MnS2 nanoplates with a diameter of about 35 nm exhibited satisfying serum stability, photo-heat conversion ability and repeated laser exposure stability. The hydrogel encapsulation did not negatively influence the above features of the photothermal agent. The nanoplates loaded in situ hydrogel shows a phase transition at body temperature and, as a result, a long retention in vivo. CONCLUSIONS: The photothermal agent embedded hydrogel played a promising photothermal therapeutic effects in tumor bearing mouse model with low systemic toxicity after peritumoral administration.

[Effect of Chinese Drugs for Breaking Blood Expelling Stasis on Acute Cerebral Hemorrhage: a Prospective Randomized Double-blind Controlled Study].

OBJECTIVE: To study the safety of using Chinese drugs for breaking blood expelling stasis (CDBBES) in hypertension patients with intracerebral hemorrhage within 6 h, and to observe whether they would result in hematoma enlargement. METHODS: A prospective randomized double-blind controlled clinical study was employed. Totally 128 cerebral hemorrhage patients within 6 h were recruited from 8 research centers from October 2013 to March 2015, and finally 76 of them were included. These patients were assigned to 3 groups by simple random sampling, group A, B, and C. Patients in group A (26 cases) took whole CDBBES recipe (containing leeches and equivalent insects). Those in group B (25 cases) took CDBBES recipe (removing leech and gradfly). Those in group C (25 cases) took placebos. Medication lasted for 10 successive days. The hematoma enlargement rate within 24 h, the occurrence of adverse reactions and adverse events were observed. To guarantee the safety of this trial, an interim analysis of first level unblinding was used. RESULTS: The hematoma enlargement rate was 11. 5% (3/26) in group A, 16. 0% (4/25) in group B, and 20. 0% (5/25) in group C. There was no statistical difference in the hematoma enlargement rate among the 3 groups (X² =0. 823, P =0. 682). Adverse reactions and adverse events occurred in 7 cases, 1 patient with acute myocardial infarction, 1 with chest op- pression and palpitation, 2 with diarrhea in group A. No patient had adverse reaction or adverse event in group B. And diarrhea occurred in 3 patients of group C. CONCLUSION: The interim analysis of first level unblinding showed that hematoma enlargement within 6 h was not resulted from using CDBBES.