A Rationally Designed Micellar Nanocarrier for the Delivery of Hydrophilic Methotrexate in Psoriasis Treatment

"Click" amphotericin B in prodrug nanoformulations for enhanced systemic fungemia treatment

Severe nephrotoxicity and infusion-related side effects pose significant obstacles to the clinical application of Amphotericin B (AmB) in life-threatening systemic fungal infections. In pursuit of a cost-effective and safe formulation, we have introduced multiple phenylboronic acid (PBA) moieties onto a linear dendritic telodendrimer (TD) scaffold, enabling effective AmB conjugation via boronate chemistry through a rapid, high yield, catalysis-free and dialysis-free "Click" drug loading process. Optimized AmB-TD prodrugs self-assemble into monodispersed micelles characterized by small particle sizes and neutral surface charges. AmB prodrugs sustain drug release in circulation, which is accelerated in response to the acidic pH and Reactive Oxygen Species (ROS) in the infection and inflammation. Prodrugs mitigate the AmB aggregation status, reduce cytotoxicity and hemolytic activity compared to Fungizone®, and demonstrate superior antifungal activity to AmBisome®. AmB-PEG5kBA4 has a comparable maximum tolerated dose (MTD) to AmBisome®, while over 20-fold increase than Fungizone®. A single dose of AmB-PEG5kBA4 demonstrates superior efficacy to Fungizone® and AmBisome® in treating systemic fungal infections in both immunocompetent and immunocompromised mice.

Telodendrimer functionalized hydrogel platform for sustained antibiotics release in infection control

Wound infection commonly causes delayed healing, especially in the setting of chronic wounds. Local release of antibiotics is considered a viable approach to treat chronic wounds. We have developed a versatile telodendrimer (TD) platform for efficient loading of charged antibiotic molecules via a combination of multivalent and synergistic charge and hydrophobic interactions. The conjugation of TD in biocompatible hydrogel allows for topical application to provide sustained antibiotic release. Notably, a drug loading capacity as high as 20 % of the drug-to-resin dry weight ratio can be achieved. The payload content (PC) and release profile of the various antibiotics can be optimized by fine-tuning TD density and valency in hydrogel based on the charge and hydrophobic features of the drug, e.g., polymyxin B (PMB), gentamycin (GM), and daptomycin (Dap), for effective infection control. We have shown that hydrogel with moderately reduced TD density demonstrates a more favorable release profile than hydrogel with higher TD density. Antibiotics loaded in TD hydrogel have comparable antimicrobial potency and reduced cytotoxicity compared to the free antibiotics due to a prolonged, controlled drug release profile. In a mouse model of skin and soft tissue infection, the subcutaneous administration of PMB-loaded TD hydrogel effectively eliminated the bacterial burden. Overall, these results suggest that engineerable TD hydrogels have great potential as a topical treatment to control infection for wound healing. STATEMENT OF SIGNIFICANCE: Wound infection causes a significant delay in the wound healing process, which results in a significant financial and resource burden to the healthcare system. PEGA-telodendrimer (TD) resin hydrogel is an innovative and versatile platform that can be fine-tuned to efficiently encapsulate different antibiotics by altering charged and hydrophobic structural moieties. Additionally, this platform is advantageous as the TD density in the resin can also be fine-tuned to provide the desired antibiotic payload release profile. Sustained antibiotics release through optimization of TD density provides a prolonged therapeutic window and reduces burst release-induced cytotoxicity compared to conventional antibiotics application. Studies in a preclinical mouse model of bacteria-induced skin and soft tissue infection demonstrated promising therapeutic efficacy as evidenced by effective infection control and prolonged antibacterial efficacy of antibiotics-loaded PEGA-TD resin. In conclusion, the PEGA-TD resin platform provides a highly customizable approach for effective antibiotics release with significant potential for topical application to treat various bacterial wound infections to promote wound healing.

Engineering Telodendrimer Nanocarriers for Monomeric Amphotericin B Delivery

Systemic fungal infections are an increasingly prevalent health problem. Amphotericin B (AmB), a hydrophobic polyene antibiotic, remains the drug of choice for life-threatening invasive fungal infections. However, it has dose-limiting side effects, including nephrotoxicity. The efficacy and toxicity of AmB are directly related to its aggregation state. Here, we report the preparation of a series of telodendrimer (TD) nanocarriers with the freely engineered core structures for AmB encapsulation to fine-tune AmB aggregation status. The reduced aggregation status correlates well with the optimized antifungal activity, attenuated hemolytic properties, and reduced cytotoxicity to mammalian cells. The optimized TD nanocarrier for monomeric AmB encapsulation significantly increases the therapeutic index, reduces the in vivo toxicity, and enhances antifungal effects in mouse models with Candida albicans infection in comparison to two common clinical formulations, i.e., Fungizone and AmBisome.

A Promising Approach of Dermal Targeting of Antipsoriatic Drugs via Engineered Nanocarriers Drug Delivery Systems for Tackling Psoriasis

Psoriasis is a complex autoimmune skin condition with a significant genetic component. It causes skin inflammation and is characterized by flaky, silvery reddish spots that can worsen with age. This condition results from an impaired immunological response of T-cells and affects 2-5% of the global population. The severity of the illness determines the choice of treatment. Topical treatments are commonly used to treat psoriasis, but they can have several adverse effects. Biological therapy is another option for treating specific types of psoriasis. Recently, new nanoformulations have revolutionized psoriasis treatment. Various nanocarriers, such as liposomes, nanostructured lipid nanoparticles, niosomes, and nanoemulsions, have been developed and improved for drug delivery. The use of nanocarriers enhances patient compliance, precise drug delivery, and drug safety. This review aims to suggest new nanocarrier-based drug delivery systems for treating psoriasis. It discusses the importance of nanocarriers and compares them to traditional treatments. Anti-psoriatic drugs have also been investigated for cutaneous delivery using nanocarriers. The review also covers various factors that influence dermal targeting. By highlighting several relevant aspects of psoriasis treatment, the review emphasizes the current potential of nanotechnology. Using nanocarriers as a drug delivery technique may be a promising alternative treatment for psoriasis.

Nanocrystal-based gel of apremilast ameliorates imiquimod-induced psoriasis by suppressing inflammatory responses

Apremilast is 'difficult-to-deliver' in stratum corneum and viable layers (viable epidermis, dermis) owing to its modest lipophilicity and poor aqueous solubility, respectively. The objective of the present research was to develop apremilast nanocrystal-based gel for enhanced anti-psoriatic efficacy for the treatment of psoriasis. Nanosuspension was generated by wet media milling with a mean particle size of 200 nm. In-vivoefficacy of nanocrystal-based gels was evaluated in the imiquimod-induced psoriatic plaque model. Nanocrystal-based gel (1% and 3% w/w) improved phenotypic, histopathological features of psoriatic skin and attenuated splenic hypertrophy, psoriasis area severity scoring. Enzyme-linked immunosorbent assay was performed to evaluate levels of psoriatic biochemical markers indicating a significant decrease in the concentration of cytokines such as IL-23, IL-17A, IL-6 and TNF-α by nanocrystal-based gels (1% and 3% w/w) over disease induced group. Skin irritation study revealed that nanocrystal-based gel was significantly less irritating than the positive control. These results suggest that nanocrystal-based gel of apremilast can be an effective strategy for the management of psoriasis.

Temperature-Responsive Nano-Biomaterials from Genetically Encoded Farnesylated Disordered Proteins

Despite broad interest in understanding the biological implications of protein farnesylation in regulating different facets of cell biology, the use of this post-translational modification to develop protein-based materials and therapies remains underexplored. The progress has been slow due to the lack of accessible methodologies to generate farnesylated proteins with broad physicochemical diversities rapidly. This limitation, in turn, has hindered the empirical elucidation of farnesylated proteins' sequence-structure-function rules. To address this gap, we genetically engineered prokaryotes to develop operationally simple, high-yield biosynthetic routes to produce farnesylated proteins and revealed determinants of their emergent material properties (nano-aggregation and phase-behavior) using scattering, calorimetry, and microscopy. These outcomes foster the development of farnesylated proteins as recombinant therapeutics or biomaterials with molecularly programmable assembly.

Injectable and pH-responsive self-assembled peptide hydrogel for promoted tumor cell uptake and enhanced cancer chemotherapy

Chemotherapy is the main treatment for cancer therapy. However, its anti-tumor efficiency is always impaired by the poor bioavailability and low tumor accumulation of chemotherapeutic drugs. The variation between the tumor microenvironment and normal tissue has been recognized as an effective tool to improve drug anti-tumor efficiency. Herein, we developed an injectable, pH-responsive, in situ self-assembled drug-peptide hydrogel (MTX-KKFKFEFEF(DA)) for highly efficient local tumor chemotherapy with few side effects. The small molecule drug, methotrexate (MTX), and pH-responsive linker, 2,3-dimethylmaleic anhydride (DA), were facilely conjugated onto the chain of the KKFKFEFEF peptide via an amidation reaction. The negatively charged drug-peptide (pH 7.4) can be activated to be positive and achieve a sol-gel phase transition under an acidic microenvironment (pH 6.5) both in vitro and in vivo, resulting in highly efficient cellular uptake and endocytosis capacities. Moreover, the in vivo anti-tumor therapeutic effect revealed that the MTX-KKFKFEFEF(DA) hydrogel exhibits long-term tumor retention time, much better tumor inhibition rate and negligible side effects after intratumoral injection into breast tumor-bearing mice. Therefore, this study reveals a versatile strategy for fabricating a pH-responsive drug-peptide hydrogel to improve the chemotherapeutic efficacy of drugs in cancer treatment.

Micelles Based on Lysine, Histidine, or Arginine: Designing Structures for Enhanced Drug Delivery

Natural amino acids and their derivatives are excellent building blocks of polymers for various biomedical applications owing to the non-toxicity, biocompatibility, and ease of multifunctionalization. In the present review, we summarized the common approaches to designing and constructing functional polymeric micelles based on basic amino acids including lysine, histidine, and arginine and highlighted their applications as drug carriers for cancer therapy. Different polypeptide architectures including linear polypeptides and dendrimers were developed for efficient drug loading and delivery. Besides, polylysine- and polyhistidine-based micelles could enable pH-responsive drug release, and polyarginine can realize enhanced membrane penetration and gas therapy by generating metabolites of nitric oxide (NO). It is worth mentioning that according to the structural or functional characteristics of basic amino acids and their derivatives, key points for designing functional micelles with excellent drug delivery efficiency are importantly elaborated in order to pave the way for exploring micelles based on basic amino acids.

Facial Solid-Phase Synthesis of Well-Defined Zwitterionic Amphiphiles for Enhanced Anticancer Drug Delivery

Serum protein adsorption on the nanoparticle surface determines the biological identity of polymeric nanocarriers and critically impacts the in vivo stability following intravenous injection. Ultrahydrophilic surfaces are desired in delivery systems to reduce the serum protein corona formation, prolong drug pharmacokinetics, and improve the in vivo performance of nanotherapeutics. Zwitterionic polymers have been explored as alternative stealth materials for biomedical applications. In this study, we employed facial solid-phase peptide chemistry (SPPC) to synthesize multifunctional zwitterionic amphiphiles for application as a drug delivery vehicle. SPPC facilitates synthesis and purification of the well-defined dendritic amphiphiles, yielding high-purity and precise architecture. Zwitterionic glycerylphosphorylcholine (GPC) was selected as a surface moiety for the construction of a ultrahydrophilic dendron, which was coupled on solid phase to a hydrophobic dendron using multiple rhein (Rh) molecules as drug-binding moieties (DBMs) for doxorubicin (DOX) loading via pi-pi stacking and hydrogen bonding. The resulting zwitterionic amphiphilic Janus dendrimer (denoted as GPC₈-Rh₄) showed improved stabilities and sustained drug release compared to the analogue with poly(ethylene glycol) (PEG) surface (PEG^5k-Rh₄). In vivo studies in xenograft mouse tumor models demonstrated that the DOX-GPC₈-Rh₄ nanoformulation significantly improved anticancer effects compared to DOX-PEG^5k-Rh₄, owing to the improved in vivo pharmacokinetics and increased tumor accumulation.

Telodendrimers: Promising Architectural Polymers for Drug Delivery

Architectural complexity has played a key role in enhancing the efficacy of nanocarriers for a variety of applications, including those in the biomedical field. With the continued evolution in designing macromolecules-based nanoparticles for drug delivery, the combination approach of using important features of linear polymers with dendrimers has offered an advantageous and viable platform. Such nanostructures, which are commonly referred to as telodendrimers, are hybrids of linear polymers covalently linked with different dendrimer generations and backbones. There is considerable variety in selection from widely studied linear polymers and dendrimers, which can help tune the overall composition of the resulting hybrid structures. This review highlights the advances in articulating syntheses of these macromolecules, and the contributions these are making in facilitating therapeutic administration. Limited progress has been made in the design and synthesis of these hybrid macromolecules, and it is through an understanding of their physicochemical properties and aqueous self-assembly that one can expect to fully exploit their potential in drug delivery.