Psoriasis
Conditions
Keywords
Psoriasis, Microcirculation, TRPV1
Brief summary
Psoriasis is a chronic inflammatory cutaneous disease, affecting 3% of the French population. Among psoriatic patients, 80% feel pain or cutaneous discomfort related to their pathology. Neurogenic inflammation's role in psoriasis has recently been put forward by a study showing that TRPV1 ion channels are necessary to establish psoriasiform inflammation in mice. The investigators hypothesize that there is a link between cutaneous sensory neuropathies and altered cutaneous microcirculation during psoriasis. In order to test this hypothesis, local vasodilators will be delivered to patients by iontophoresis and their skin blood flow in response to these molecules will be followed by laser Doppler recordings. Two recordings will be performed for each patient, both on a psoriasis plaque and on uninvolved skin, in order for the patient to be his own internal control.
Interventions
Acetylcholine will be locally delivered to patients by iontophoresis successively on healthy skin and on psoriasis plaque (order determined by randomization).
OTHERSodium Nitroprussiate iontophoresis
Sodium Nitroprussiate will be locally delivered to patients by iontophoresis successively on healthy skin and on psoriasis plaque (order determined by randomization).
OTHERppi water iontophoresis
ppi water will be locally delivered to patients by iontophoresis successively on healthy skin and on psoriasis plaque (order determined by randomization).
OTHERLaser Doppler recording
Skin blood flow will be recorded by laser Doppler during 2 minutes before iontophoresis, and during 30 minutes following iontophoretic delivery of vasodilators.
Sponsors
Hospices Civils de Lyon
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
20 Years to 40 Years
Healthy volunteers
No
Inclusion criteria
* Type I psoriasis * Psoriasis plaques on the patient's back
Exclusion criteria
* BMI \> 25 * Diabetic patient * Arteriovenous disease history * Ongoing anti-inflammatory treatment * Major cardiovascular history (\<3 months) * Hypertension * Topical treatment on the back skin (\<7 days) * Systemic treatment (steroids, methotrexate, retinoids, cyclosporine) or phototherapy (\<1 month) * Pregnant women * Subject within exclusion period following a previous or ongoing biomedical study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| skin blood flow variation | at the latest 3 months after inclusion | Skin blood flow variation on healthy skin and on psoriasis plaque will be measured by Laser Doppler in response to iontophoretic delivery of vasodilator substances (sodium nitroprussiate and acetylcholine) and ppi water. Skin blood flow will be recorded during 2 minutes before iontophoresis, and during 30 minutes following iontophoretic delivery of vasodilators. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Sensory detection threshold | at the latest 3 months after inclusion | Increasing size of Von Frey filaments will be placed onto patients' skin to assess sensory detection threshold. |
| Potential discomfort sensation thresholds | at the latest 3 months after inclusion | Increasing size of Von Frey filaments will be placed onto patients' skin to assess potential discomfort sensation threshold. |
| Heat sensitivity | at the latest 3 months after inclusion | Heat sensitivity will be assessed using hot (50°C) and cold (4°C) water |
Countries
France
Outcome results
None listed