Echinacea purpurea-derived alkylamides exhibit potent anti-inflammatory effects and alleviate clinical symptoms of atopic eczema

J Dermatol Sci. 2017 Oct;88(1):67-77. doi: 10.1016/j.jdermsci.2017.05.015. Epub 2017 May 27.


Background: Atopic eczema (AE) is a chronic inflammatory and pruritic skin disease. There is still an unmet need for topical anti-inflammatory and anti-pruritic substances exhibiting an excellent safety profile. The endocannabinoid system is known to regulate various aspects of cutaneous barrier and immune functions, thus targeting it may be a valid approach for alleviating the symptoms of AE.

Objective: To assess the putative efficacy of Echinacea purpurea-derived alkylamides (Ec. extract) activating cannabinoid (CB)-2 receptors in exerting anti-inflammatory effects and alleviating symptoms of AE.

Methods: In vitro anti-inflammatory efficiency was investigated by monitoring the effects of Ec. extract on poly-(I:C)-induced pro-inflammatory cytokine expression (Q-PCR) and release (ELISA) of HaCaT keratinocytes. Irritancy and sensitization potential (assessed by Human Repeat Insult Patch Test; Clinical trial 1); clinical efficiency in alleviating symptoms of AE (Clinical trial 2) as well as effects on human skin structure and lipid content (Clinical trial 3 followed by transmission electron microscopy and HPTLC) were investigated in randomized double blind clinical trials.

Results: Ec. extract significantly reduced mRNA expression as well as release of poly-(I:C)-induced pro-inflammatory cytokines (IL-6 and IL-8) in keratinocytes. Thus, not surprisingly, the well-tolerated (Clinical trial 1) Ec. extract-based cream reduced local SCORAD statistically significantly, not only compared to baseline, but also compared to the comparator (Clinical trial 2). Of great importance, besides the in vitro anti-inflammatory effects, administration of the Ec. extract-based cream also resulted in significantly higher levels of overall epidermal lipids, ceramide EOS (ω-esterified fatty acid+sphingosine sphingoid base), and cholesterol at Day 15 compared to baseline as well as significantly greater numbers of intercellular lipid lamellae in the intercellular space (Clinical trial 3).

Conclusion: The investigated Ec. extract shows great potential in alleviating cutaneous symptoms of AE, and by exerting remarkable anti-inflammatory actions and restoring the epidermal lipid barrier, it will be very likely a well-tolerated, powerful novel ingredient for the adjuvant therapy of AE.

Keywords: Atopic eczema; Echinacea purpurea; Endocannabinoid system; Inflammation; Skin barrier.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Antipruritics / pharmacology
  • Antipruritics / therapeutic use*
  • Cell Line
  • Chemotherapy, Adjuvant / methods
  • Child
  • Cytokines / metabolism
  • Dermatitis, Atopic / drug therapy*
  • Dermatitis, Atopic / pathology
  • Double-Blind Method
  • Echinacea / chemistry*
  • Enzyme-Linked Immunosorbent Assay
  • Extracellular Space / chemistry
  • Female
  • Healthy Volunteers
  • Humans
  • Keratinocytes
  • Lipids / analysis
  • Male
  • Microscopy, Electron, Transmission
  • Middle Aged
  • Patch Tests
  • Plant Extracts / pharmacology
  • Plant Extracts / therapeutic use*
  • Polyunsaturated Alkamides / pharmacology
  • Polyunsaturated Alkamides / therapeutic use*
  • Pruritus / drug therapy*
  • Pruritus / pathology
  • Real-Time Polymerase Chain Reaction
  • Receptor, Cannabinoid, CB2 / agonists*
  • Skin / cytology
  • Skin / drug effects
  • Skin / pathology
  • Skin / ultrastructure
  • Young Adult


  • Antipruritics
  • CNR2 protein, human
  • Cytokines
  • Lipids
  • Plant Extracts
  • Polyunsaturated Alkamides
  • Receptor, Cannabinoid, CB2