At the forefront of medical research, the treatment of acute lung injury (ALI) has always been a difficult problem.

Severe inflammatory response is the core pathological link in the occurrence and development of ALI. Its close relationship with oxidative stress makes the generation of excessive reactive oxygen species (ROS) a key target for treatment.

Traditional treatments, such as supportive care, mechanical ventilation, and glucocorticoids, while effective to some extent, have significant limitations. In recent years, small molecule antioxidants and nanomaterials have shown promise as potential treatment options for ALI due to their ability to scavenge excess ROS.

The limitations of natural antioxidants and the rise of artificial nanozymes

Natural antioxidants, such as catalase (CAT), glutathione peroxidase (GPx), and superoxide dismutase (SOD), play a central role in neutralizing ROS.

However, these natural enzymes have problems such as structural instability, high production cost, large molecular weight and potential immunogenicity, which limit their widespread clinical application.

In contrast, artificial nanozymes, as a class of materials with enzyme-like activity, have become a viable alternative to natural enzymes due to their higher stability, lower cost and adjustable catalytic properties.

Cascade nanozymes VTMn-CDs: a new hope for precision treatment of ALI

Recently, Professor Jiang Jingying's team from the School of Medical Science and Engineering at Beihang University published a groundbreaking study in the internationally renowned journal Chemical Engineering Journal (IF=13.19) .

This study constructed a manganese-doped carbon dots (CDs) cascade nanozyme, VTMn-CDs, which targets the transmembrane protein VCAM-1 and exhibits multiple antioxidant enzyme activities, providing a new strategy for the precise treatment of ALI.

01. Unique advantages of carbon dots (CDs)

As fluorescent carbon-based nanomaterials with a size less than 10 nanometers, CDs possess photoluminescence, excellent biocompatibility, water dispersibility, and exceptional stability, making them ideal candidates for applications in sensing, bioimaging, and diagnostics. Furthermore, the potential of CDs as nanozymes is also gaining increasing attention.

02. Innovative Design of VTMn-CDs

Using a thermal decomposition method, researchers developed a VCAM-1-targeting VTMn-CDs cascade nanozyme that incorporates tannic acid (TA) and manganese (Mn). Tannic acid, a natural antioxidant rich in phenolic hydroxyl groups, and manganese, a key cofactor for superoxide dismutase (SOD), together endow VTMn-CDs with potent ROS-scavenging capabilities.

In vitro and in vivo experiments validate the excellent therapeutic effect of VTMn-CDs

01. In vitro experiments

The researchers selected H2O2 as an oxidant and used RAW 264.7 cells and HUVECs cells as cell models to detect the antioxidant activity of VTMn-CDs through CCK8, confocal microscopy and immunofluorescence experiments.

The results showed that VTMn-CDs exhibited good biocompatibility and focused on mitochondria to exert efficient antioxidant and anti-inflammatory effects.

02. In vivo experiments

Using the YAN-30012 Yuyan pulmonary atomization device, LPS was injected into the lungs of mice to simulate ALI inflammation and ROS production.

VTMn-CDs served as the experimental group, and DXMS served as the positive control group. The experimental results showed that the Yuyan pulmonary drug delivery device could evenly disperse the drug in the lung tissue, greatly increasing the reliability of the experimental results.

VTMn-CDs exhibited highly effective antioxidant and anti-inflammatory effects, significantly alleviating the inflammatory response.

Exploration of the mechanism of action of VTMn-CDs

The study further explored the mechanism by which VTMn-CDs treat ALI mice. The results showed that VTMn-CDs exerted a potent therapeutic effect by inhibiting the TLR/MyD88/NF-κB signaling pathway, alleviating oxidative stress and downregulating the expression of inflammatory molecules.

Yuyan Pulmonary Atomizer Device: A Powerful Tool for Precise Drug Delivery

Yuyan Instruments' pulmonary aerosol drug delivery device (Microsprayer Aerosolizer), also known as an intratracheal aerosol drug delivery device, is an intratracheal aerosol drug delivery device specially designed for small animals such as mice, rats, and guinea pigs.

The device uses an aerosol atomizing micro-nozzle in a stainless steel capillary cannula to deliver a trace amount of liquid medicine deep into the animal's trachea, achieving quantitative atomization into aerosol drug delivery in the trachea.

Compared with traditional oral or injection administration, pulmonary administration can act directly on the lungs, avoid the first-pass effect of the liver, reduce the dosage, reduce adverse reactions, quickly absorb the drug into the systemic circulation, and maintain the biological activity of the drug.

01. Product Features

1. Suitable for a variety of small animals, and can also be customized for large animals.

2. Direct administration into the trachea, without first-pass elimination, results in minimal systemic drug effects.

3. The drug can be liquid or dry powder to meet different needs.

4. Micro-precision administration, the minimum drug dosage is 25μL (liquid).

5.90% of the drug atomization diameter is less than 30μm (liquid) and is evenly distributed in the lung tissue.

6. Easy to use, safe and stable, made of stainless steel, strong, stable and corrosion-resistant.

02. Advantages and application prospects of pulmonary aerosol drug delivery

Pulmonary aerosol administration can directly deliver drugs to the lungs in a quantitative manner, achieve the treatment of local or systemic diseases, avoid the first-pass effect of the liver, reduce the dosage, reduce adverse reactions, quickly absorb drugs into the systemic circulation, and maintain the biological activity of drugs.

This new drug delivery method only requires a single atomization, and the dosage can be accurately controlled, providing an effective way to deliver biomacromolecules such as proteins and peptides.

Application example: A team from Fudan University used the Yuyan Instruments lung atomization drug delivery device to deliver the new SARS-CoV-2 Omicron single-domain antibody to the lungs of mice through atomization inhalation, providing new possibilities for the treatment of COVID-19.