In recent years, with the development of nanomaterials, a slice of nanomaterials has been demonstrated to possess high catalytic activity similar to natural enzymes and counter the dilemmas including easy inactivation and low yield natural of enzymes, which are labeled as nanozymes. The catalytic activity of nanozymes could be easily regulated by size, structure, surface modification and other factors. In comparison with natural enzymes, nanozymes featured with a more stable structure, economical preparation and preservation, diversity of functions and adjustable catalytic activity, thus becoming the potentially ideal substitute for natural enzymes. Generally, the are mainly three types containing metal oxide nanozymes, noble metal nanozymes and carbon-based nanozymes, owing various applications in biomedical, energy and environmental fields. In this review, to summarize the recent representative applications of nanozymes, and potentially explore the scientific problems in this field at the same time, we are going to discuss the catalytic mechanisms of diverse nanozymes, with the emphasis on their applications in the fields of tumor therapy, anti-inflammatory and biosensing, hoping to help and guide the future development of nanozymes.

Glutathione (GSH) is involved in and regulates important physiological functions of the body as an essential antioxidant. GSH plays an important role in anti-oxidation, detoxification, anti-aging, enhancing immunity and anti-tumor activity. Herein, based on the physiological properties of GSH in different diseases, mainly including the strong reducibility of GSH, high GSH content in tumor cells, and the NADPH depletion when GSSH is reduced to GSH, we extensively report the design principles, effect, and potential problems of various nano-drugs in diabetes, cancer, nervous system diseases, fluorescent probes, imaging, and food. These studies make full use of the physiological and pathological value of GSH and develop excellent design methods of nano-drugs related to GSH, which shows important scientific significance and prominent application value for the related diseases research that GSH participates in or responds to.

Cell-derived drug carriers have increasingly gained the interest of the scientific community due to their ability to imitate various natural properties of their source cells. We developed theranostics nanoplatforms composed of mesoporous silica nanoparticles (MSNs), indocyanine green (ICG) molecules, microRNAs-137 (miR-137), red-blood-cell membranes (RM), and tumor-targeting cyclo Arg-Gly-Asp-d-Phe-Cys peptides (cRGD(fC)), which were abbreviated as MSNs/ICG/miR/RM/RGD particles. These particles possessed photothermal and gene therapy properties due to ICG and miR-137, respectively. The photothermal conversion efficiency was ~18.7%. Upon 808 nm light irradiation, the tumor inhibition rate reached 94.9% with dosage of 10 mg/kg. The developed nanoplatform possessed unique properties, such as exceptional biocompatibility, immune escaping, and specific recognition, which was also used for near-infrared fluorescence, photoacoustic (PA) bimodal imaging-guided tumor recognition.

With aging of population, changing of living habits, and intake of high-fat diet, more and more people have been suffering from cardio-cerebral apoplexy. The synchronous treatment of cardio-cerebral conditions based on an integral strategy may bring benefit to the better clinical efficacy. The simultaneously-targeting delivery of active molecules by nanoscale carriers to heart and brain remains unmet problem. The physiological difference of targets between heart and brain makes it a huge challenge which one targeting ligand modification acquires the delivery of two organs and treatment, simultaneously. Traditionally, dually targeting strategies are introduced to enhance the selectivity for one aimed tissue and delivery efficiency of these particles. However, the interference between two targeting ligands on the surface of nanoscale carriers may influence the affinity of these ligands with their receptors or transporters, resulting to the change distribution of carriers. Herein, we observed that how anti-cardiac troponin I (cTnI) antibody (Ab) conjugated with the linker, polyethylene glycol (PEG), on the surface of liposomes influenced the affinity of mannose derivatives with transporter and regulated distribution of these vesicles in the heart and brain. The dually targeting liposomes can target to the heart and brain tissue simultaneously by the regulation length of PEG chain linking with p -pentanoic acid phenyl-α-D-acetylmannosamine (Ac₄MAN). These results may bring benefit to design the multi-modification of nanocarriers and the treatment of cardio-cerebral diseases.

The expression and function of long noncoding RNAs (lncRNAs) in the development of hypoxic pulmonary hypertension, especially in the proliferation of pulmonary artery smooth muscle cells (PASMCs) are largely unknown. Here, we characterized the expression of lncRNA-maternally expressed gene 3 (lncRNA-MEG3) was significantly increased and primarily located in the cytoplasm of PASMCs by hypoxia. LncRNA-MEG3 knockdown by lung-specific delivery of small interfering RNAs (siRNAs) significantly prevented the development of hypoxic pulmonary hypertension in vivo . Silencing of lncRNA-MEG3 by siRNAs and gapmers attenuated PASMC responses to hypoxia in vitro . Mechanically, we found that lncRNA-MEG3 acts as a molecular sponge of microRNA-328 (miR-328); upon hypoxia, lncRNA-MEG3 interacts and sequesters miR-328, leading to the upregulation of insulin-like growth factor 1 receptor (IGF1R). Additionally, higher expression of lncRNA-MEG3 and IGF1R, and lower expression of miR-328 were observed in PASMCs of iPAH patients. These data provide insight into the contribution of lncRNA-MEG3 in hypoxia pulmonary hypertension. Upregulation of lncRNA-MEG3 sequesters cytoplasmic miR-328, eventually leading to the expression of IGF1R, revealing a regulatory mechanism by lncRNAs in hypoxia-induced PASMC proliferation.