Antioxidant carbon dot nanozymes alleviate depression in rats by restoring the gut microbiome

Depression is a significant challenge to diagnose and treat. Among the factors influencing depression onset and severity, there is growing evidence for chemical imbalances that generate oxidative stress throughout the body.

To address this problem, researchers reporting in the journal Langmuir have developed antioxidant carbon dot nanozymes (synthetic enzyme-like substances) that reduced oxidative stress, rebalanced gut microbes and alleviated stress-induced depression in rats.

One of the potential hallmarks of depressive disorder is a buildup of reactive oxygen- and nitrogen-containing compounds, which can overwhelm the body's natural defenses. The resulting oxidative stress impacts gut health by disrupting the balance of microbes, which can trigger inflammation and alter brain and neuronal function.

To correct this problem, Jihong Huang, Weiwei He and colleagues synthesized enzyme-like substances with a strong antioxidant capacity to reduce the reactive species and thereby restore gut microbe balance and alleviate depression.

The researchers created carbon dot nanozymes (CDzymes) by polymerizing glucose and the amino acid histidine to ensure antioxidant activity while maintaining biocompatibility. The CDzymes neutralized a range of reactive species in solution and in cultured mouse nerve cells without signs of toxicity.

Image source: Jia et al. (2024), Langmuir.