Effect of Dermal Rejuvenation on the UVB Response of Geriatric Skin

Not Applicable

Completed

Brief Summary: The objective of this study is to examine the ability of dermal rejuvenation therapies to protect geriatric skin from ultraviolet light (UVB)-induced carcinogenesis. Skin cancers (including basal cell carcinoma and squamous cell carcinoma) are the most common types of malignancy and are related to UVB exposure in sunlight. UVB-irradiation of skin causes specific DNA damage to keratinocytes that can lead to cancer-causing mutations if they are allowed to persist in proliferating cells. Moreover, the incidence of skin cancers is much greater in elderly over younger individuals. The objective of the present study is to build upon our previous data and test the effect of a non ablative Nd:YAG laser (LaserGenesis) of a localized area of skin on dermal IGF-1 production and UVB-mediated keratinocyte effects. Treatment of skin using a non ablative high-peak power microsecond pulsed 1064 nm Nd:YAG laser (Cutera's LaserGenesisTM laser) leads to papillary dermal heating. The laser targets the microvasculature and stimulates collagen production while protecting the epidermis. Generally, Laser Genesis is used clinically to improve irregularities in the contour, texture, and color of the skin. Laser Genesis is also used to help treat photoaging by increasing collagen formation, suggesting that it stimulates fibroblast activity and thus possibly increases levels of protective IGF-1.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

Subjects who have underlying diseases that could affect wound healing (eg, diabetes mellitus)
on medications that are known photosensitizers,
or have a history of abnormal scarring (eg, keloids) will be excluded.

Subjects will be asked the screening questions below as part of the inclusion/exclusion criteria

How old are you?
Do you regularly use tanning beds?
Are you being treated with light therapy?
Have you had any diseases that got worse when you went in the sun?
Are you taking any medications that warn you to stay out of the sun?
Have you ever had a reaction to medications that were applied to your skin?
When cuts or wounds on your skin heal, are the scars abnormally large or take a long time to heal?
Do you have diabetes mellitus or have you ever had high blood sugar?

Arm && Interventions

Group	Intervention	Description
UV Light	UV Light (Laser Genesis)	-

Primary Outcome Measures

Name	Time	Method
Difference in Basal Layer Keratinocytes Positive for Both Ki67 and Thymine Dimers	untreated and LaserGenesis treated, three months after treatment, 24 hours after 350 J/m2 of UVB	Number of double positive cells per 1000 total basal layer keratinocytes

Secondary Outcome Measures

Name	Time	Method
Relative Level of IGF-1 mRNA in the Skin	untreated and LaserGenesis treated, three months after treatment	IGF-1 mRNA per 100,000 beta-2 microglobulin mRNA. Beta-2 microglobulin mRNA was used as a reference gene for this assessment and that the data represent number of copies IGF-1/100,000 copies b2-microglobulin.