Glutathione-mediated intracellular release of anti-inflammatory N-acetyl-L-cysteine from mesoporous silica nanoparticles

Mesenchymal stromal cell-derived extracellular vesicles as nanotherapeutics for concanavalin a-induced hepatitis: modulating the gut‒liver axis

BACKGROUND

As cell-free nanotherapeutics, extracellular vesicles derived from mesenchymal stem cells (MSC-EVs) have shown potential therapeutic action against liver diseases. However, their effects on autoimmune hepatitis (AIH) are not yet well understood.

METHODS AND RESULTS

In this study, we utilized a well-established concanavalin A (Con A)-induced fulminant hepatitis mouse model to investigate the effects of MSC-EVs on AIH. We found that MSC-EVs provide significant protection against Con A-induced hepatitis in C57BL/6 male mice, with their effectiveness being critically dependent on the gut microbiota. MSC-EVs modulate the composition of the gut microbiota, particularly by increasing the abundance of norank_f__Muribaculaceae, and impact liver metabolic profiles, leading to significant amelioration of liver injury. The identification of Acetyl-DL-Valine as a protective metabolite underscores the therapeutic potential of targeting gut‒liver axis interactions in liver diseases.

CONCLUSION

Overall, our data demonstrate that MSC-EVs exhibit nanotherapeutic potential in Con A-induced hepatitis and provide new insights into the treatment of autoimmune hepatitis.

A redox-responsive strategy using mesoporous silica nanoparticles for co-delivery of siRNA and doxorubicin

Co-delivery of gene and drug therapies for cancer treatment remains a major goal of nanocarrier research.

Functionalized mesoporous silica nanoparticles with redox-responsive short-chain gatekeepers for agrochemical delivery

The controlled release of salicylic acid (SA), a key phytohormone, was mediated by using a novel decanethiol gatekeeper system grafted onto mesoporous silica nanoparticles (MSNs). The decanethiol was conjugated only to the external surfaces of the MSNs through glutathione (GSH)-cleavable disulfide linkages and the introduction of a process to assemble gatekeepers only on the outer surface so that the mesopore area can be maintained for high cargo loading. Raman and nitrogen sorption isotherm analyses confirmed the successful linkage of decanethiol to the surface of MSNs. The in vitro release of SA from decanethiol gated MSNs indicated that the release rate of SA in an environment with a certain amount of GSH was significantly higher than that without GSH. More importantly, in planta experiments showed the release of SA from decanethiol gated MSNs by GSH induced sustained expression of the plant defense gene PR-1 up to 7 days after introduction, while free SA caused an early peak in PR-1 expression which steadily decreased after 3 days. This study demonstrates the redox-responsive release of a phytohormone in vitro and also indicates the potential use of MSNs in planta as a controlled agrochemical delivery system.

γ-PGA-coated mesoporous silica nanoparticles with covalently attached prodrugs for enhanced cellular uptake and intracellular GSH-responsive release

Poor cellular uptake of drug delivery carriers and uncontrolled drug release remain to be the major obstacles in cancer therapy due to their low delivery efficiency. In this study, a multifunctional intracellular GSH (glutathione)-responsive silica-based drug delivery system with enhanced cellular uptake capability is developed. Uniform 50 nm colloidal mesoporous silica nanoparticles (MSNs) with mercaptopropyl-functionalized core and silanol-contained silica surface (MSNs-SHin ) are designed and fabricated as a platform for drug covalent attachment and particle surface modification. Doxorubicin (DOX) with primary amine group as an anticancer model drug is covalently conjugated to the mesopores of MSNs-SHin via disulfide bonds in the presence of a heterobifunctional linker (N-Succinimidyl 3-(2-pyridyldithio) propionate). Poly(γ-glutamic acid) (γ-PGA) can be coated onto the particle surface by sequential electrostatic adsorption of polyethyleneimine (PEI) and γ-PGA. The constructed delivery system exhibits enhanced cellular uptake via a speculated γ-glutamyl transpeptidase (GGT)-mediated endocytosis pathway and controlled drug release capacity via intracellular GSH-responsive disulfide-bond cleavage, and thus significantly inhibits the growth of cancer cells. The multifunctional delivery system paves a new way for developing high-efficient particle-based nanotherapeutic approach for cancer treatment.