Polygonum chinense L. extracts regulate OxInflammation through Nrf2/HO-1/NF-κB signaling pathways

Area of Science:

• Phytochemistry
• Immunology
• Pharmacology

Background:

• Polygonum chinense L. (PCL) is traditionally used for inflammatory and infection-related conditions.
• Pharmacological basis for PCL's traditional uses is not fully understood, especially in immune cells under oxidative stress.

Purpose of the Study:

• Investigate antioxidant and anti-inflammatory activities of PCL ethanol extract.
• Elucidate molecular mechanisms in lipopolysaccharide (LPS)-stimulated porcine alveolar macrophages (PAMs).

Main Methods:

• UHPLC-MS/MS for PCL extract characterization.
• In vitro antioxidant assays (DPPH, ABTS, FRAP) and inflammation-related assays.
• Assessment of oxidative stress markers (ROS, MDA, SOD, GSH, T-AOC) in LPS-stimulated PAMs.
• Analysis of Nrf2/HO-1 and NF-κB pathways via RT-qPCR, western blotting, and inhibitor studies.

Main Results:

• PCL extract exhibited strong antioxidant capacity and inhibited protein denaturation and protease activity.
• PCL extract reduced LPS-induced cytotoxicity (LDH, NO), oxidative stress (ROS, MDA), and restored antioxidant levels (SOD, GSH, T-AOC).
• PCL extract upregulated Nrf2/HO-1 and downregulated NF-κB, TNF-α, IL-1β, and IL-6, with effects partially mediated by Nrf2.

Conclusions:

• PCL ethanol extract possesses significant in vitro antioxidative and anti-inflammatory properties.
• Mechanisms involve Nrf2/HO-1 pathway activation and NF-κB pathway inhibition.
• Findings support PCL's traditional applications and its potential for managing oxidative stress-related inflammatory diseases.