Self-assembled nanoplatform-mediated co-delivery of brusatol to sensitize sorafenib for hepatocellular carcinoma treatment

Sorafenib (Sor), recognized as a frontline multi-kinase inhibitor, constitutes the primary targeted therapy for hepatocellular carcinoma (HCC). Despite its potential, many HCC patients exhibit reduced responsiveness to Sor, thereby undermining its therapeutic efficacy. Recent studies highlight the importance of nuclear factor erythroid-2-related factor 2 (Nrf2) activation in HCC, which contributes to Sor resistance. Brusatol (Bru), a plant-derived Nrf2 inhibitor, counteracts this resistance but faces challenges due to its poor solubility in aqueous media. In this study, we developed a glutathione (GSH)-responsive nanoplatform that effectively dispersed in water for the co-delivery of Bru and Sor (B/S NP). This approach enhanced Bru's therapeutic efficacy and increased Sor sensitivity in HCC. Our nanoplatform significantly reduced Nrf2 expression, thereby increasing Sor sensitivity both in vitro and in vivo, while presenting a favorable biosafety profile. These findings suggest that the nanoplatform-mediated co-delivery of Bru and Sor offers an innovative approach to enhance Sor's effectiveness in HCC treatment.

pH-sensitive release of nitric oxide gas using peptide-graphene co-assembled hybrid nanosheets

Nitric oxide (NO) donating drugs such as organic nitrates have been used to treat cardiovascular diseases for more than a century. These donors primarily produce NO systemically. It is however sometimes desirable to control the amount, location, and time of NO delivery. We present the design of a novel pH-sensitive NO release system that is achieved by the synthesis of dipeptide diphenylalanine (FF) and graphene oxide (GO) co-assembled hybrid nanosheets (termed as FF@GO) through weak molecular interactions. These hybrid nanosheets were characterised by using X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, zeta potential measurements, X-ray photoelectron spectroscopy, scanning and transmission electron microscopies. The weak molecular interactions, which include electrostatic, hydrogen bonding and π-π stacking, are pH sensitive due to the presence of carboxylic acid and amine functionalities on GO and the dipeptide building blocks. Herein, we demonstrate that this formulation can be loaded with NO gas with the dipeptide acting as an arresting agent to inhibit NO burst release at neutral pH; however, at acidic pH it is capable of releasing NO at the rate of up to 0.6 μM per minute, comparable to the amount of NO produced by healthy endothelium. In conclusion, the innovative conjugation of dipeptide with graphene can store and release NO gas under physiologically relevant concentrations in a pH-responsive manner. pH responsive NO-releasing organic-inorganic nanohybrids may prove useful for the treatment of cardiovascular diseases and other pathologies.

Applications of peptide-based nanomaterials in targeting cancer therapy

To meet the demand for precision medicine, researchers are committed to developing novel strategies to reduce systemic toxicity and side effects in cancer treatment. Targeting peptides are widely applied due to their affinity and specificity, and their ability to be high-throughput screened, chemically synthesized and modified. More importantly, peptides can form ordered self-assembled structures through non-covalent supramolecular interactions, which can form nanostructures with different morphologies and functions, playing crucial roles in targeted diagnosis and treatment. Among them, in targeted immunotherapy, utilizing targeting peptides to block the binding between immune checkpoints and ligands, thereby activating the immune system to eliminate cancer cells, is an advanced therapeutic strategy. In this mini-review, we summarize the screening, self-assembly, and biomedical applications of targeting peptide-based nanomaterials. Furthermore, this mini-review summarizes the potential and optimization strategies of targeting peptides.

Dipeptide nanostructures: Synthesis, interactions, advantages and biomedical applications

Short peptides are important in the design of self-assembled materials due to their versatility and flexibility. Self-assembled dipeptides, a group of peptide nanostructures, have highly attractive uses in the field of biomedicine. Recently these materials have proved to be important nanostructures because of their biocompatibility, low-cost and simplicity of synthesis, functionality/easy tunability and nano dimensions. Although there are different studies on peptide and protein-based nanostructures, more information about self-assembled nanostructures for dipeptides is still required to discover the advantages, challenges, importance, synthesis, interactions, and applications. This review describes and discusses the self-assembled dipeptide nanostructures especially for biomedical applications.

Folate-conjugated hydrophobicity modified glycol chitosan nanoparticles for targeted delivery of methotrexate in rheumatoid arthritis

BACKGROUND

Targeted delivery to the Rheumatoid arthritis (RA) which is characterized by destruction and degeneration of bones due to chronic inflammation is of great need. RA being a chronic autoimmune disorder might result in severe disability and morbidity. A targeted delivery system is designed to deliver methotrexate (MTX) for RA.

METHODS

Here, we synthesized folic acid (FA) conjugated hydrophobically modified glycol chitosan (GC) self-assembled nanoparticles (FA-GC-SA) for the targeted delivery of MTX to RA. The FA conjugation and hydrophobic modification of GC by stearic acid (SA) was confirmed by Fourier-transform infrared spectroscopy (FTIR). The FA-GC-SA was exploited for developing targeted nanoparticles encapsulating MTX by the ionic gelation method. The particles were characterized and evaluated for their targeting potential in in vitro cell culture studies. Further their in vivo efficacy in arthritis induced rats using collagen was also evaluated.

RESULTS

FTIR confirms the successful modification of GC-SA and FA-GC-SA. The FA-GC-SA-MTX of size 153 ± 9 nm were prepared with high encapsulation efficiency of MTX. The FA-GC-SA-MTX size was further confirmed by transmission electron microscopy (TEM). In vitro cell studies revealed the superior efficacy of FA-GC-SA-MTX in cell cytotoxicity. Also, significantly higher cellular uptake of FA functionalized FA-GC-SA-MTX was observed in comparison to non-functionalized GC-SA-MTX attributed to folate receptors (FRs) mediated endocytosis. In vivo results confirms the potential of FA-GC-SA-MTX which reduces reduces the pro-inflammatory cytokines, paw thickness, and arthritis score in collagen induced rats.

CONCLUSION

The results shows that FRs targeted FA-GC-SA-MTX has superior efficacy in the treatment of RA.

Design of a Thiol-Responsive, Traceless Prodrug with Rapid Self-Immolation for Cancer Chemotherapy

Prodrugs can be formed by chemical modification of the existing active pharmaceutical ingredients (APIs); however, this often sacrifices their functional efficacy. Self-immolative linkers have recently attracted attention, as they can be designed to release pristine APIs. Herein, we report a strategy to generate a self-immolative prodrug (SIP) that can release pristine doxorubicin (DOX). Compared to conventional linkers, the key SIP DOX (KSIP-DOX) developed here can rapidly and quantitatively release the API due to its strong leaving group after reduction by thiol groups, which are present in tumors. KSIP-DOX has enhanced cellular uptake and improved anticancer efficacy, demonstrating its utility for cancer treatment.

Recent advances in the fabrication and bio-medical applications of self-assembled dipeptide nanostructures

Molecular self-assembly is a widespread natural phenomenon and has inspired several researchers to synthesize a compendium of nano/microstructures with widespread applications. Biomolecules like proteins, peptides and lipids are used as building blocks to fabricate various nanomaterials. Supramolecular peptide self-assembly continue to play a significant role in forming diverse nanostructures with numerous biomedical applications; however, dipeptides offer distinctive supremacy in their ability to self-assemble and produce a variety of nanostructures. Though several reviews have articulated the progress in the field of longer peptides or polymers and their self-assembling behavior, there is a paucity of reviews or literature covering the emerging field of dipeptide-based nanostructures. In this review, our goal is to present the recent advancements in dipeptide-based nanostructures with their potential applications.

Intranasal delivery of Paclitaxel encapsulated nanoparticles for brain injury due to Glioblastoma

Brain injury is a common cause for physical and emotional effects to the large number of populations. Moreover, glioblastoma is the tumor in brain with no possible treatment leading to death. The blood-brain barrier's makes the treatment more difficult by preventing the drugs to reach central nervous system. Paclitaxel (PTX) encapsulated Poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), PTX-PLGA-NPs were developed using emulsification method. The PTX-PLGA-NPs were characterized using Malvern Zetasizer and Scanning Electron Microscopy and were evaluated for their cytotoxicity in U87MG cells. PTX-PLGA-NPs were prepared using single emulsion method having size of 154 ± 22.19 nm with zeta potential of -23.7 mV. The PTX-PLGA-NPs were spherical in shape and have dose dependent cytotoxicity on U87MG cells. The PTX was released from the particles with initial burst release followed by sustained release pattern. The biodistribution was studied in mice with glioblastoma model using ¹²⁵I radiolabeled PTX-PLGA-NPs and anti-glioblastoma was studied with PTX-PLGA-NPs. The biodistribution studies revealed PTX-PLGA-NPs after intranasal administration resulted in higher in vivo uptake with high anti-glioblastoma efficacy. The results suggest that PTX-PLGA-NPs administered through intranasal route have potential in the treatment of glioblastoma.

Brinzolamide loaded core-shell nanoparticles for enhanced coronial penetration in the treatment of glaucoma

A neurodegenerative disorder, glaucoma is a leading cause of blindness in the world. The conventional treatment strategies do not allow the significant penetration of the drug in the cornea. Therefore, we prepare a brinzolamide (Brz) loaded core-shell nanoparticles (NPs) to enhance the coronial penetration of the drug and thus treating the glaucoma. The shell of the NPs was composed of phosphatidylserine (PS; 1,2-diacyl-sn-glycero-3-phospho-L-serine), whereas the core of the NPs contains the Brz encapsulated in brinzolamide–phosphatidylserine–polymer poly-(DL-lactic acid-co-glycolic acid)–phosphatidylserine (Brz-PS-PLGA). The synthesis of Brz-PS-PLGA was achieved by using a coaxial electrospray process (CEP), which allows the preparation of the particles in a single step. The size of Brz-PS-PLGA with PS shell and brinzolamide–poly (lactic-co-glycolic) acid (Brz-PLGA) without shell was 571 ± 27.02 nm and 456 ± 19.17 nm, respectively. The charges on the surface of Brz-PS-PLGA and Brz-PLGA were (-) 27.45 ± 2.98 mV and (-) 19.47 ± 2.83 mV. The transmission electron microscopy images clearly reveal the PS shell as a light black layer over the dark black PLGA core. The CEP allows the high encapsulation of Brz in Brz-PS-PLGA where percentage of entrapment efficiency for Brz-PS-PLGA was 88.13 ± 6.43%. The release study conducted in a simulated tear fluid revealed the sustained release patterns of Brz from Brz-PS-PLGA and these were nontoxic to the cells as revealed by the cytotoxicity studies. Further, the Brz-PS-PLGA enhanced the coronial penetration of Brz and was capable of significantly reducing the intraocular pressure (IOP) after administration to the rabbit eye in comparison to the Brz-PLGA and free Brz. The results clearly suggest that the PS coating significantly enhances the capability of the particles in reducing IOP.

Targeted degradation of immune checkpoint proteins: emerging strategies for cancer immunotherapy

Cancer immunotherapy using immune-checkpoint blockade has displayed promising clinical effects, but prevalent antibody-based inhibitors face multiple challenges such as low response rate, acquired resistance, and adverse effects. The intracellular expression of PD-1/PD-L1 in recycling endosomes and their active trafficking to membrane highlight the importance of depleting rather than interfering with checkpoint proteins. Preclinical investigations on the therapeutic effects of lead compounds that function by degrading immune checkpoint ligands and receptors have reported highly promising results. By harnessing the degradation capabilities of the lysosome, proteasome and autophagosomes, different small molecules and peptides potently induced degradation of checkpoint proteins and enhanced anti-tumor immunity. Both in vitro and in vivo experiments support the therapeutic efficacy of these molecules. Thus, targeted degradation through endo-lysosomal, autophagic, proteasomal, or endoplasmic reticulum-related pathways may provide promising strategies for tackling the challenges in cancer immunotherapy.

Rhein laden pH-responsive polymeric nanoparticles for treatment of osteoarthritis

Osteoarthritis (OA) is a condition associated with severe inflammation, cartilage destruction and degeneration of joints. Rhein (Rh) is an effective anti-inflammatory drug with proven efficacy in in-vitro and in-vivo models. pH sensitive Rh and NH₄HCO₃ laden poly (lactic-co-glycolic acid (PLGA) nanoparticles (NPs) (Rh-PLGA-NPs@NH₄) are developed for an effective treatment of OA. The Rh-PLGA-NPs@NH₄ are prepared along with Rh-PLGA-NPs as a control by double emulsion method. Rh-PLGA-NPs@NH₄ was characterized for their size, shape, morphology and encapsulation efficiency (EE). The effect of pH on release of Rh from Rh-PLGA-NPs@NH₄ was studied at different pH. Further, the cytotoxicity effect of Rh-PLGA-NPs@NH₄ on THP-1 cells were evaluated. Anti-inflammatory efficacy was evaluated on LPS stimulated THP-1 cells and the release of pro-inflammatory cytokines was evaluated and compared with control. The size of Rh-PLGA-NPs@NH₄ and Rh-PLGA-NPs was found to be 190.7 ± 1.2 nm and 134.6 ± 2.4 nm respectively with poly dispersity (PDI) 0.14 and 0.15. The zeta potential of Rh-PLGA-NPs@NH₄ was found to be -22 ± 1.12 mV. Rh-PLGA-NPs@NH₄ were uniform, smooth and spherical shape as confirmed using electron microscopy analysis. Rh-PLGA-NPs@NH₄ release the Rh more effectively in the low pH of synovial fluid environment (SFE). Rh-PLGA-NPs@NH₄ also significantly affect inflammatory cytokines TNF-α and IL-1β and reduced their release in LPS stimulated THP-1 cells. Reactive oxygen species (ROS), a mediator responsible for the cartilage collapse was also found to be reduced. Results proposes that Rh-PLGA-NPs could provide therapeutic solution to those patients who suffer from chronic joint ailments by reducing the progression of OA.