Indocyanine Green-Conjugated Magnetic Prussian Blue Nanoparticles for Synchronous Photothermal/Photodynamic Tumor Therapy

Indocyanine green(ICG) is capable of inducing a photothermal effect and the production of cytotoxic reactive oxygen species for cancer therapy. However, the major challenge in applying ICG molecules for antitumor therapy is associated with their instability in aqueous conditions and rapid clearance from blood circulation,which causes insufficient bioavailability at the tumor site.Herein, we conjugated ICG molecules with Prussian blue nanoparticles enclosing a Fe_3O_4 nanocore, which was facilitated by cationic polyethyleneimine via electrostatic adsorption. The nanocarrier-loaded ICG formed stable aggregates that enhanced cellular uptake and prevented fluorescence quenching. Moreover, the strong superparamagnetism of the Fe_3O_4 core in the obtained nanocomposites further improved cellular internalization of the drugs guided by a localized magnetic field. The therapeutic efficacy of this nanoplatform was evaluated using tumor models established in nude mice, which demonstrated remarkable tumor ablation in vivo due to strong photothermal/photodynamic effects. This study provides promising evidence that this multifunctional nanoagent might function as an efficient mediator for combining photothermal and photodynamic cancer therapy.

Microenvironment responsive pod-structured astaxanthin nanocarrier for ameliorating inflammatory bowel disease

Anti-inflammatory drugs targeting inflammatory bowel disease(IBD)have attracted considerable attention but still face low therapeutic outcomes and frequent side effects.Astaxanthin(ATX),a natural ketone,possesses potent antioxidant and anti-inflammatory properties.However,it faces problems such as poor water solubility,photothermal instability,and low bioavailability.Here,we employed a supramolecular encapsulation strategy to create a nanoscale oral delivery system for ATX(referred to as FC-ATX NPs)by coupling fucoidan(FUC)with chitosan oligosaccharides(COS).The obtained FC-ATX NPs exhibited a particular“bean pod”structure with uniform size,good encapsulation efficiency,excellent physical and chemical stability,pH-triggered intestinal targeted slow-release properties,and potent antioxidant capacity.In vitro cell culture experiments showed that FC-ATX NPs promoted cellular uptake and scavenged excessive intracellular reactive oxygen species(ROS).In mouse models of colitis,FC-ATX NPs enhanced the drug absorption of intestinal epithelial cells and effectively accumulated at the site of inflammation.This work provides an efficient approach to enhance the bioavailability of ATX and has excellent application potential as an oral targeted delivery system for colitis therapy.

Self-shrinking supramolecular nanoparticles syndicate energy suppression and NIR-II mild photothermal amplification of mitochondrial oxidative stress for breast cancer therapy

Photothermal therapy(PTT)may lead to healthy tissue damage,tumor metastasis,and recurrence,which makes mild photothermal therapy(mild PTT)stand out.However,overcoming heat resistance,insufficient therapeutic effect,and poor photothermal conversion efficiency has become new challenge.Herein,we report a dynamic supramolecular nanocarrier formed from amide-sericin and aldehyde-polyhydroxy glucan(denoted as SDA),the loose cavity of which can be filled by using the pharmaceutical combination of lonidamine(LND)and NIR-II photothermal agent of IR-1061,producing SDLI with a tighter inner hole,smaller and uniform particle size and excellent stability due to multiple pulling forces.Moreover,the intricate internal network structure prevents the hydrophobic IR-1061 from forming aggregates in the small cavity,and the photothermal conversion efficiency(PCE)can reach 48.9%.At the acidic tumor microenvironment of pH 6.5,the controlled release of LND can solve the problem of heat resistance of NIR-II mild PTT and significantly improve the therapeutic effect of NIR-II mild PTT.Meanwhile,SDLI also shows a reasonable tumor inhibition rate,so the synergistic strategy of inhibiting tumor energy metabolism and NIR-II mild PTT to magnify mitochondrial oxidative stress,continuous cell stress state-induced immunogenic cell death to promote the induction of tumor apoptosis is proposed to achieve more effective cancer treatment.

Bioresponsive immune-booster-based prodrug nanogel for cancer immunotherapy

The combination of chemotherapy and immunotherapy motivates a potent immune system by triggering immunogenic cell death(ICD), showing great potential in inhibiting tumor growth and improving the immunosuppressive tumor microenvironment(ITM). However, the therapeutic effectiveness has been restricted by inferior drug bioavailability. Herein, we reported a universal bioresponsive doxorubicin(DOX)-based nanogel to achieve tumor-specific co-delivery of drugs. DOX-based mannose nanogels(DM NGs) was designed and choosed as an example to elucidate the mechanism of combined chemo-immunotherapy. As expected, the DM NGs exhibited prominent micellar stability, selective drug release and prolonged survival time, benefited from the enhanced tumor permeability and prolonged blood circulation. We discovered that the DOX delivered by DM NGs could induce powerful antitumor immune response facilitated by promoting ICD. Meanwhile, the released mannose from DM NGs was proved as a powerful and synergetic treatment for breast cancer in vitro and in vivo, via damaging the glucose metabolism in glycolysis and the tricarboxylic acid cycle. Overall, the regulation of tumor microenvironment with DOX-based nanogel is expected to be an effectual candidate strategy to overcome the current limitations of ICD-based immunotherapy, offering a paradigm for the exploitation of immunomodulatory nanomedicines.

ROS-responsive cyclodextrin nanoplatform for combined photodynamic therapy and chemotherapy of cancer

Cyclodextrin(CD) has special spatial structure and well biological safety,so it has been widely used for constructing CD-based na noplatforms.Through functionalization,cyclodextrin can form various stimulusresponse nanoplatforms,such as pH,temperature,redox,light and magnetic fields.In this study,we designed a highly sensitive reactive oxygen species(ROS)-responsive polymer PCP which encapsulated doxorubicin(DOX) and purpurin 18(P18) to achieve the syne rgy of photodynamic and chemotherapy.The high content of reactive oxygen species(ROS) in the tumor microenvironment(TME) triggers the cleavage of the borate bond of MPEG-CD-PHB(PCP),thereby promoting the re lease of drugs.When irradiated with nea rinfrared laser,the photosensitizer P18 released by polymer micelles can produce reactive oxygen species to promote cell apoptosis.Compared with monotherapy,a series of experiments confirmed that our micelles had enhanced anti-cancer activity.This work was beneficial to the design of ROS-responsive materials and provides an effective strategy for the application of collaborative anti-tumor therapy.

Cylindrical polymer brushes-anisotropic unimolecular micelle drug delivery system for enhancing the effectiveness of chemotherapy

Polymer systems can be designed into different structures and morphologies according to their physical and chemical performance requirements,and are considered as one of the most promising controlled delivery systems that can effectively improve the cancer therapeutic index.However,the majority of the polymer delivery systems are designed to be simple spherical nanostructures.To explore morphology/size-oriented delivery performance optimization,here,we synthesized three novel cylindrical polymer brushes(CPBs)by atom transfer radical polymerization(ATRP),which were cellulose-g-(CPT-b-OEGMA)(CCO)with different lengths(~86,~40,and~21 nm).The CPBs are composed of bio-degradable cellulose as the carrier,poly(ethylene glycol)methyl ether methacrylate(OEGMA)as hydrophily block,and glutathione(GSH)-responsive hydrophobic camptothecin(CPT)monomer as loaded anticancer drug.By controlling the chain length of the initiator,three kinds of polymeric prodrugs with different lengths(CCO-1,CCO-2,and CCO-3)could be self-organized into unimolecular micelles in water.We carried out comparative studies of three polymers,whose results verified that the shorter CPBs exhibited higher drug release efficiency,more cellular uptake,and enhanced tumor permeability,accompanied by shortened blood circulation time and lower tumor accumulation.As evidenced by in vivo experiments,the shorter CPBs exhibited higher anti-tumor efficiency,revealing that the size advantage has a higher priority than the anisotropic structure advantage.This provided vital information as to design an anisotropic polymer-based drug delivery system for cancer therapy.

Polydopamine(PDA)-activated cobalt sulfide nanospheres responsive to tumor microenvironment(TME)for chemotherapeutic-enhanced photothermal therapy

Most recently,cobalt sulfide(CoS)nanospheres(NSs)have been demonstrated as an ideal high-efficient photothermal agent for tumor elimination.Howeve r,the surface of CoS NSs is lack of functio nal chemical groups or active radicals to incorporate therapeutic agents,which tremendously hinders their versatile utilization in medical field.Here,surface activation of CoS NSs was realized through the growth of polydopamine(PDA)in situ via alkaline-triggered polymerization.Upon the formation of CoS@PDA NSs,thiol-polyethylene glycol(SH-PEG)and chemotherapeutic agent of doxorubicin(DOX)were loaded onto the particle surface by means ofπ-πelectrostatic interaction and Michael addition reactions.Assynthesized CoS@PDA/PEG/DOX(CoPPD)NSs exhibited an admirable photothermal property and high loading capacity of DOX(44.6%).Furthermore,drug release can be accelerated under a more acidic pH condition mimicking tumor microenvironment(TME),ascribed to the protonation of amino group in DOX molecules.Finally,a strong chemotherapeutic-enhanced photothermal therapeutic effect was demonstrated toward solid tumor under near-infrared(NIR)light irradiation without causing significant systemic toxicity.In this regard,this paradigm may offer valuable guidance for the design of multifunctional CoS-based nanoagents for medical treatment.

The Systematic Evaluation of Physicochemical and Biological Properties In Vitro and In Vivo for Natural Silk Fibroin Nanoparticles

Nanoparticle-based theranostics has served as a preferential technology for diagnosis and treatment of diseases.However,there are still massive challenges in constructing the ideal platform,which hopefully integrate various characteristics such as easy preparation,multiple utilization,and high therapeutic effect and safety into a single system.Herein,we reported a drug delivery system-based on natural silk fibroin(denoted as SF NPs),and systematically evaluated the physicochemi-cal properties,biological properties and the biosafety assessment of SF NPs.The in vitro and in vivo experimental results confirmed that SF NPs showed high stability,low blood hemolysis and the universal delivery ability of drugs.Additionally,the SF NPs could rapidly enter into cells due to its nanoscale size,and had a weak cytotoxicity against MCF-7,4T1 and L929 cells.Meanwhile,the SF NPs showed enhanced tumor permeability in a simulative model of multicellular spheroids,combined with excellent in vivo biosafety and the negligible organ injury,demonstrate that SF-based nanomedicine presents the utilization potentiality for drug delivery and may provide a new view for cancer treatment.

Microenvironment-responsive chemotherapeutic nanogels for enhancing tumor therapy via DNA damage and glutathione consumption

Although targeted therapy and immunotherapy are now shining in the treatment of some cancers,chemotherapy is still the cornerstone of drug treatment for many cancer patients.The emergence of chemotherapy prodrugs can improve the drug activity and reduce the side effects of chemotherapy.When used,the tumor microenvironment has characteristics different from normal tissues,and the existence of the microenvironment provided a more convenient way to design responsive nanodrugs.Herein,we designed a glutathione(GSH)-responsive prodrug nanogels for enhancing tumor chemotherapy.In the nanogels of HHNP,10-hydroxycamptothecin(HCPT)played an essential role in killing cancer cells.HCPT was jointed with a cross-linker agent with disulfide bond and was further coated with polyethylene glycol,which not only prolonged the half-life of the drug,but also made HCPT accurate transport to the tumor fractions and achieved precise and controllable release.The proposal of HHNP effectively retained the biological activity of the drug,and introduced functions such as targeting,selective release and biodegradation,which greatly improved the medical efficiency of the drug and effectively reduced the toxic and side effects.This chemotherapeutic prodrug nanogel offers a new window for constructing efficient drug delivery platform.

Development of annulus fibrosus tissue construct with hydrogel coils containing pre-conditioned mesenchymal stem cell

Low back pain associated with degenerative disc diseases has been a major health concern that brings suffering to the patients physically and economically.Many existing therapeutic strategies provide shortterm relief of symptoms rather than treatment of the underlying cause.Development of an engineered tissue for disc regeneration is still in its infancy due to the limited autologous healthy disc cell source from the patients.It is also challenging to mimic the complexity of micro-architecture in the native disc tissue that determine their unique structural properties.To date,simple tissue models that mimic the annulus fibrosus(AF)micro-environment for understanding the potential of mesenchymal stem cells(MSCs)in AF tissue engineering are still lacking.In this study,the assembly of a coiled hydrogel microfiber has shown its capability to encapsulate MSCs and create an engineered tissue model that mimics the multiple lamellae of native AF.Using this model,we investigated the potential of MSCs that were previously induced by ascorbic acid(AA).Compared to non-induced MSCs,AA-induced MSCs exhibited significant increase in AF-associated biomarkers during later development in the engineered AF tissue model and also encouraged collagen accumulation through the down-regulated catabolic gene MMP1 and upregulated anti-catabolic gene TIMP1.Furthermore,AA-induced MSCs exhibited a Col2/Col1 ratio closer to that of a native AF tissue.These results suggested that AA-induced MSCs could be a potential cell source for AF tissue engineering and this established tissue model may provide a simple tool for successful AF tissue engineering strategies in the future.