Silencing of Gasdermin D by siRNA-Loaded PEI-Chol Lipopolymers Potently Relieves Acute Gouty Arthritis through Inhibiting Pyroptosis.

Gasdermin D (GSDMD) plays a causal role in NOD-like receptor protein 3 (NLRP3) inflammasome-mediated pyroptosis eruption, which has been regarded as a potential therapeutic target for pyroptosis-related diseases including acute gouty arthritis. In the present study, the synthesized PEI-Chol (cholesterol grafted polyethylenimine) was assembled with GSDMD small interfering RNA (siRNA) to form PEI-Chol/siGSDMD polyplexes, which provided high transfection efficiency for siRNA-mediated GSDMD knockdown. Then we evaluated the effect of GSDMD siRNA-loaded PEI-Chol on inflammatory cascades in bone-marrow-derived macrophages (BMDMs) and acute gouty arthritis animal models under MSU exposure. When accompanied by pyroptosis blockade and decreased release of interleukin-1 beta (IL-1ß), NLRP3 inflammasome activation was also suppressed by GSDMD knockdown in vivo and in vitro. Moreover, in MSU-induced acute gouty arthritis mice, blocking GSDMD with siRNA significantly improved ankle swelling and inflammatory infiltration observed in histopathological analysis. Furthermore, investigation using a mouse air pouch model verified the effect of siGSDMD-loaded PEI-Chol on pyroptosis of recruited macrophages and related signaling pathways in response to MSU. These novel findings exhibited that GSDMD knockdown relieved acute gouty arthritis through inhibiting pyroptosis, providing a possible therapeutic approach for MSU-induced acute gouty arthritis molecular therapy using PEI-Chol as a nucleic acid delivery carrier.

Biomimetic Hybrid Nanozymes with Self-Supplied H+ and Accelerated O2 Generation for Enhanced Starvation and Photodynamic Therapy against Hypoxic Tumors.

Nanozymes as artificial enzymes that mimicked natural enzyme-like activities have received great attention in cancer diagnosis and therapy. Biomimetic nanozymes require more consideration regarding complicated tumor microenvironments to mimic biological enzymes, thus achieving superior nanozyme activity in vivo. Here we report a biomimetic hybrid nanozyme (named rMGB) which integrates natural enzyme glucose oxidase (GOx) with nanozyme manganese dioxide (MnO2) by mutual promotion for maximizing the enzymatic activity of MnO2 and GOx. Under hypoxia environment, we observed that MnO2 could react with endogenous H2O2 to produce O2 for enhancing the catalytic efficiency of GOx for starvation therapy. Meanwhile, we confirmed that glucose oxidation generated gluconic acid and further improved the catalytic efficiency of MnO2 subsequently. The biochemical reaction cycle, consisting of MnO2, O2, GOx, and H+, was triggered by the tumor microenvironment and accelerated each other so as to achieve self-supplied H+ and accelerate O2 generation, enhancing the starvation therapy, alleviating tumor hypoxia and accelerating the reactive oxygen species generation in photodynamic therapy. This biomimetic hybrid nanozyme would further facilitate the development of biological nanozymes for cancer treatment.

Cationic fluorescent polymer core-shell nanoparticles for encapsulation, delivery, and non-invasively tracking the intracellular release of siRNA.

A multifunctional nanocarrier for encapsulation and delivery of short interfering RNA (siRNA) has been realized using cationic fluorescent polymer core-shell nanoparticles. The nanocarrier has good biocompatibility and high transfection efficiency over the most popular transfection reagent, Lipofectamine 2000. Fluorescence resonance energy transfer within the nanocarrier provides a non-invasive and label-free method to track the intracellular release of siRNA.

A fluorescence-Raman dual-imaging platform based on complexes of conjugated polymers and carbon nanotubes.

The present study describes a flexible nanoplatform based on electrostatic assembly of conjugated polyelectrolytes (CPEs) and carboxylated multi-walled carbon nanotubes (cMWNTs). It is demonstrated that the obtained nanocomposites inherit intrinsic optical properties of CPEs and characteristic Raman vibration modes of MWNTs, providing a fluorescence-Raman dual-imaging method for intracellular tracking and locating of MWNTs. We suggest that the cellular internalization of the CPE-cMWNT nanocomposites is a surface charge-dependent process. The strengths of this nanoplatform include satisfying biocompatibility, enhanced protein-repellent property, and ease of implementation, making it available for both in vitro and in vivo applications.