Triptolide inhibits neutrophil extracellular trap formation

Area of Science:

• Immunology
• Pharmacology

Background:

• Triptolide (PG490), a triterpene dicyclic oxide, is known to induce apoptosis in RAW 264.7 cells by increasing reactive oxygen species (ROS) and nitric oxide (NO).
• Neutrophil extracellular traps (NETs) are crucial for anti-bacterial processes in the human body.

Purpose of the Study:

• To investigate the effect of triptolide (PG490) on the formation of neutrophil extracellular traps (NETs).

Main Methods:

• Peripheral blood neutrophils were isolated from healthy volunteers and incubated with PG490.
• NETs formation and intracellular ROS levels were measured using fluorescence microscopy and a multifunctional microplate reader.
• SYTOX Green staining was used to detect NETs, and fluorescence intensity was quantified.

Main Results:

• PG490 significantly inhibited NETs formation compared to the 12-myristate-13-acetate (PMA) control group, as indicated by decreased SYTOX Green fluorescence.
• While PMA stimulation increased intracellular ROS, PG490 did not significantly alter ROS levels in the presence of PMA.
• The observed inhibition of NETs by PG490 was not associated with changes in cellular ROS.

Conclusions:

• Triptolide (PG490) inhibits neutrophil extracellular trap (NET) production in vitro.
• This inhibition mechanism is independent of cellular reactive oxygen species (ROS) levels.
• PG490, derived from Tripterygium wilfordii Hook F, may have potential in suppressing diseases associated with NET formation.