Paeoniflorin inhibited LL-37 (cathelicidin) expression and macrophage-mediated rosacea inflammation through the SOCS3-ASK1-p38 pathway, reducing the abnormal immune response that drives this chronic skin condition.
Targets LL-37 overexpressionPaeoniflorin specifically reduces the LL-37 cathelicidin peptide overexpression that drives rosacea inflammation — addressing the root cause, not just symptoms
What the researchers found
Paeoniflorin promoted SOCS3 expression and inhibited LPS-induced TLR2 and LL-37 expression through SOCS3-ASK1-p38 cascade in macrophages. Rosacea lesions showed increased LL-37 and CD68+ macrophage infiltration. SOCS3 siRNA reversed PF's effects, confirming the mechanism.
Why it matters
LL-37 overexpression is a recognized driver of rosacea inflammation, but current treatments don't specifically target this pathway. PF offers a mechanism-based approach to treating the root cause of rosacea rather than just managing symptoms.
The numbers in context
Pathway: SOCS3-ASK1-p38; reduced TLR2 and LL37; CD68+ macrophage infiltration in lesions; siRNA confirmation
How the study worked
Clinical tissue analysis + in vitro mechanistic study. Immunohistochemistry of granulomatous rosacea lesions vs peripheral tissue. RAW 264.7 macrophage cell model with LPS stimulation. PF treatment effects on SOCS3, ASK1-p38, TLR2, and LL-37. SOCS3 siRNA knockdown for mechanism confirmation.
Who was studied
RAW 264.7 macrophage cells; human granulomatous rosacea tissue samples
What this study cannot tell us
In vitro macrophage model with LPS stimulation — rosacea triggers are more complex. No in vivo rosacea model tested. PF bioavailability for topical skin application unknown. Clinical trial data needed.
How to read the evidence
Low-to-moderate evidence: combined clinical tissue analysis and mechanistic in vitro study with siRNA confirmation, but no clinical treatment trial.
When this study was published
Published 2021. LL-37-targeted therapies for inflammatory skin diseases are an active research area.
The bigger picture
LL-37/cathelicidin drives multiple inflammatory skin conditions including rosacea, psoriasis, and acne. Finding compounds that specifically reduce LL-37 overexpression could benefit millions of people with these conditions.
Questions still open
- Would topical paeoniflorin formulations effectively treat rosacea in patients?
- Does PF reduce LL-37 in other inflammatory skin conditions like psoriasis?
- Could PF be combined with standard rosacea treatments for enhanced benefit?
Common questions
What causes rosacea at the molecular level?
Could peony root help with rosacea?
Read the original research
Paeoniflorin inhibits the macrophage-related rosacea-like inflammatory reaction through the suppressor of cytokine signaling 3-apoptosis signal-regulating kinase 1-p38 pathway.
Medicine, 100(3), e23986
Citation
Liu, Zijing; Zhang, Jiawen; Jiang, Peiyu; Yin, Zhi; Liu, Yunyi; Liu, Yixuan; Wang, Xiaoyan; Hu, Liang; Xu, Yang; Liu, Wentao. (2021). Paeoniflorin inhibits the macrophage-related rosacea-like inflammatory reaction through the suppressor of cytokine signaling 3-apoptosis signal-regulating kinase 1-p38 pathway.. Medicine, 100(3), e23986. https://doi.org/10.1097/MD.0000000000023986