Using pH Abnormalities in Diseased Skin to Trigger and Target Topical Therapy.
Summary of "Using pH Abnormalities in Diseased Skin to Trigger and Target Topical Therapy."
PURPOSE:
The pH discrepancy between healthy and atopic dermatitis skin was identified as a site-specific trigger for delivering hydrocortisone from microcapsules.
METHODS:
Using Eudragit L100, a pH-responsive polymer which dissolves at pH 6, hydrocortisone-loaded microparticles were produced by oil-in-oil microencapsulation or spray drying. Release and permeation of hydrocortisone from microparticles alone or in gels was assessed, and preliminary stability data was determined.
RESULTS:
Drug release from microparticles was pH-dependent, though the particles produced by spray drying also gave significant non-pH-dependent burst release, resulting from their porous nature or from drug enrichment on the surface of these particles. This pH-responsive release was maintained upon incorporation of the oil-in-oil microparticles into Carbopol- and HPMC-based gel formulations. In vitro studies showed 4- to 5-fold higher drug permeation through porcine skin from the gels at pH 7 compared to pH 5.
CONCLUSIONS:
Permeation studies showed that the oil-in-oil-generated particles deliver essentially no drug at normal (intact) skin pH (5.0-5.5) but that delivery can be triggered and targeted to atopic dermatitis skin where the pH is elevated. The incorporation of these microparticles into Carbopol- and HPMC-based aqueous gel formulations demonstrated good stability and pH-responsive permeation into porcine skin.
Affiliation
Reading School of Pharmacy, University of Reading, Whiteknights, P.O. Box 226, Reading, RG6 6AP, UK.
Journal Details
This article was published in the following journal.
Name: Pharmaceutical research
ISSN: 1573-904X
Pages:
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/21614633
- DOI: http://dx.doi.org/10.1007/s11095-011-0488-4
Medical and Biotech [MESH] Definitions
Ultrasonic Therapy
The use of focused, high-frequency sound waves to produce local hyperthermia in certain diseased or injured parts of the body or to destroy the diseased tissue.
Skin Abnormalities
Congenital structural abnormalities of the skin.
Photochemotherapy
Therapy using oral or topical photosensitizing agents with subsequent exposure to light.
Receptors, Thyrotropin
Cell surface proteins that bind pituitary THYROTROPIN (also named thyroid stimulating hormone or TSH) and trigger intracellular changes of the target cells. TSH receptors are present in the nervous system and on target cells in the thyroid gland. Autoantibodies to TSH receptors are implicated in thyroid diseases such as GRAVES DISEASE and Hashimoto disease (THYROIDITIS, AUTOIMMUNE).
Scleroderma, Systemic
A chronic multi-system disorder of CONNECTIVE TISSUE. It is characterized by SCLEROSIS in the SKIN, the LUNGS, the HEART, the GASTROINTESTINAL TRACT, the KIDNEYS, and the MUSCULOSKELETAL SYSTEM. Other important features include diseased small BLOOD VESSELS and AUTOANTIBODIES. The disorder is named for its most prominent feature (hard skin), and classified into subsets by the extent of skin thickening: LIMITED SCLERODERMA and DIFFUSE SCLERODERMA.
PubMed Articles
Molecular analysis of Malassezia pachydermatis isolated from canine skin and ear in Korea.
We investigated Malassezia species and genotypes colonizing dogs, comparing those recovered from the ear canal with those from other anatomical body sites, as well as from diseased and healthy skin. T...
Photodynamic therapy (PDT) is a treatment option particularly well-suited for superficial (pre)malignant skin lesions due to the skin's accessibility to light. In the present study, the efficacy of to...
Predictive factors of radiation-induced skin toxicity in breast cancer patients.
ABSTRACT: BACKGROUND: To assess the factors affecting the incidence of radiation-induced dermatitis in breast cancer patients treated with adjuvant 3D conformal radiotherapy by the analysis of dosimet...
Topical calcineurin inhibitors in the treatment of atopic dermatitis - an update on safety issues.
Atopic dermatitis is a common chronic skin disorder whose management is complex. Topical corticosteroids have been the mainstay of atopic dermatitis treatment for more than 50 years but have multiple...
The sequential use of topical therapies and short-incubation photodynamic therapy for actinic keratosis (AK) has not been extensively studied. The author reports on treatment with sequential 5-fluorou...
Clinical Trials
Topical Nitrates for Myofascial Trigger Points
The purpose of this study is to determine whether a topical nitroglycerine patch applied daily over a trapezius trigger point can improve patients' symptoms. If there is improvement, this...
Mechanisms of Skin Repair by Topical Estrogen
The purpose of this study is to investigate the way by which estrogen improves the appearance of sun damaged human skin. Accumulating evidence suggests that estrogen, taken by post menopa...
Restrictive and Liberal Transfusion Strategies in Intensive Care
The most effective transfusion practice in critically ill ICU patients is unknown. Currently the data is unclear as to whether a liberal or restrictive transfusion policy is of most benefi...
Topical Aminolevulinic Acid in Patients With Nonmelanoma Skin Cancer
RATIONALE: Studying samples of tumor tissue in the laboratory from patients with nonmelanoma skin cancer that has been treated with topical aminolevulinic acid may help doctors predict how...
Topical Myristyl Nicotinate Cream on the Skin of Healthy Volunteers
RATIONALE: Chemoprevention is the use of certain drugs to keep cancer from forming. The use of topical myristyl nicotinate cream may stop skin cancer from forming. PURPOSE: This randomize...
