Zinc Gel and Epidermal Regeneration in Healthy Human Volunteers

Study Overview
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Brief Summary
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Zinc is an important metal for the maintenance of healthy skin and wound healing. Washing with detergents e.g. shower gels may deplete the zinc stores in the skin. The purpose of our study is to see whether repeated washing with zinc containing shower gel of superficial wounds will result in increased healing.

Detailed Description
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Zinc is a trace element abundantly present in skin with a concentration gradient from the upper stratum corneum layer to the basal layer. This fact probably reflects the necessity for zinc as co-factor in numerous enzymes involved in skin homeostasis and wound healing. Theoretically, showering with surfactants increases the loss of zinc by the shedding of the zinc-rich corneocytes. Thus there is a concern that this forced exfoliation will result in suboptimal zinc levels for the maintenance of physiological processes involved in epidermal homeostasis and repair. A logical development would thus be to supplement shower gel with zinc to compensate for this loss. In 30 healthy volunteers one epidermal wound (10 mm in diameter) is induced by suction and heat on each buttock. The wounds are washed with shower gel containing zinc, placebo shower gel or water (reference). The treatments are allocated by randomization ensuring that 20 wounds are washed with shower gel containing zinc, 20 wounds are washed with placebo shower gel and 20 wounds are washed with water.

Official Title
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Effects of Shower Gel With Zinc on Epidermal Regeneration

Conditions
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Denuded Epidermis

Intervention / Treatment
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* Other: Shower gel with zinc
* Other: Plain shower gel
* Other: Distilled water


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy male and female volunteers Age between18 and 65 years Written informed consent Exclusion Criteria: Smoker Active skin disease in test areas Hypersensitivity to zinc or any of the shower gel ingredients Immunosuppressive treatment Pregnant or breastfeeding females

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Shower gel with zinc<br>Zinc gel is applied daily (50 µl/cm2) to wound and surrounding noninjured skin. | Other: Shower gel with zinc<br>* Standard shower gel (Sanex) supplemented with zinc sulfate.<br>|
| Placebo Comparator: Plain shower gel<br>Plain shower gel is applied daily (50 µl/cm2) to wound and surrounding noninjured skin. | Other: Plain shower gel<br>* Standard shower gel (Sanex).<br>|
| Sham Comparator: Distilled water<br>Distilled Water is applied daily (50 µl/cm2) to wound and surrounding noninjured skin. | Other: Distilled water<br>* Sterile distilled Water.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Epidermal regeneration | Epidermal regeneration will be assessed blindly by histomorphometry in hematoxylin-eosin-stained paraffin sections of the wounds and by optical coherence tomography. | Day 4 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bacterial growth | Swabs are taken from wounds and adjacent, treated skin. | Day 4 | 
| Skin barrier function | Skin barrier function is measured by transepidermal water loss by an instrument from Cortex. | Day 4 | 
| Keratinocyte proliferation | Immunohistochemical detection of Ki67 in paraffin sections of the wounds using mouse monoclonal antibody (MIB-1). | Day 4 | 
| Matrix metalloproteinase (MMP)-1 expression | Immunohistochemical detection of MMP-1 in paraffin sections of the wounds using mouse monoclonal antibody. | Day 4 | 
| Pain | Pain is assessed on a VAS scale (0-100 mm) by the participant. | Days 0, 1, 2, 3 and 4 |