retinaldehyde and Skin-Diseases

Topics: Animals; Carrier Proteins; Cell Differentiation; Chemical Phenomena; Chemistry; Epithelium; Female; Growth; Humans; Isomerism; Male; Neoplasms; Pregnancy; Receptors, Retinoic Acid; Reproduction; Retinal Pigments; Retinaldehyde; Retinol-Binding Proteins; Skin Diseases; Structure-Activity Relationship; Tretinoin; Vitamin A; Vitamin A Deficiency

A review of recent investigations in the retinoid field is presented. Retinoic acid exerts a prophylactic and a therapeutic effect on chemically induced benign and malignant epithelial tumors in mice. In clinical studies positive therapeutic results have been obtained in patients with preneoplastic and neoplastic epithelial lesions. However, treatment with retinoic acid is limited by serious side effects (hypervitaminosis A syndrome). Therefore, the synthesis of analogs of retinoic acid (retinoids) possessing a more favorable therapeutic ratio has been initiated. Among a large series of synthesized compounds, certain aromatic analogs proved to have a particularly favorable therapeutic ratio. The structure-activity relationship of the most active retinoids is discussed including some biological data concerning prophylaxis and therapy of epithelial tumors. The total synthesis of retinoids according to various building schemes is discussed in detail. Methods for the synthesis of the cyclic end group, of the polyene chain component, and of the full retinoid skeleton are described. Metabolic studies of retinoic acid and of the most active retinoid, as well as the synthesis of some isolated metabolites are outlined. Suggestions concerning the mechanism of action of retinoids are made. Some clinical results on the treatment of acne, psoriasis and precancerous conditions are reported.

Topics: Animals; Carcinoma; Humans; Neoplasms, Experimental; Papilloma; Retinaldehyde; Skin Diseases; Skin Neoplasms; Structure-Activity Relationship; Tretinoin; Vitamin A

Dermatoporosis is an emerging clinical condition caused by chronological skin aging, long-term sun exposure and chronic use of corticosteroids; however, genomic expression in dermatoporosis and the efficacy of different therapeutic approaches to prevent and treat dermatoporosis have not been investigated so far.. We examined the possible effect of topical retinaldehyde (RAL) and defined-size hyaluronate fragments (HAFi) on the expression of hyalurosome genes potentially involved in the pathogenesis of dermatoporosis. We also explored the effect of different concentrations of HAFi on skin thickness.. 13 persons were separated into a young control group (n = 8) and a dermatoporosis group (n = 5). Topical treatment of both groups with a combination of 0.05% RAL and 1 or 0.2% HAFi was applied on the forearm twice daily for 30 days. Forearm skin biopsies of both groups were performed before and after application. Hyalurosome genes CD44, heparin-binding epidermal growth factor (HB-EGF), ErbB1, hyaluronate synthase 3 (HAS3) and Hyal2 were chosen as potential markers of dermatoporosis. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed for quantification of mRNA expression of the target hyalurosome genes. Measurement of forearm skin thickness before and after treatment was performed by ultrasonography. Analysis of the results was done by Student's t test. A p value <0.05 was considered statistically significant.. In qRT-PCR analysis the relative expression of hyalurosome (CD44, HAS3, HB-EGF) genes was found to be reduced in patients prior to topical treatment and to be notably increased following treatment. The reduced expression of CD44 and HAS3 in patients was specifically restored in dermatoporotic patients after treatment. No difference in skin thickness was observed in controls after treatment. The treatment caused a significant increase in skin thickness in dermatoporotic patients. This increase was more significant with 1% HAFi when compared to 0.2% HAFi. RAL and HAFi also caused a significant reduction in purpuric lesions in patients with dermatoporosis.. Our results indicate that topically applied RAL and HAFi regulate hyalurosome gene expression in dermatoporosis and that they show a dose-dependent effect on the correction of skin atrophy in dermatoporotic patients.

Topics: Adjuvants, Immunologic; Administration, Topical; Atrophy; Biopsy; Cell Adhesion Molecules; Dose-Response Relationship, Drug; Drug Therapy, Combination; Follow-Up Studies; Forearm; Gene Expression Regulation; Heparin-binding EGF-like Growth Factor; Humans; Hyaluronan Receptors; Hyaluronic Acid; Hyaluronoglucosaminidase; Keratinocytes; Real-Time Polymerase Chain Reaction; Retinaldehyde; Retrospective Studies; RNA, Messenger; Skin; Skin Diseases; Time Factors; Treatment Outcome; Ultrasonography

Dermatoporosis is a novel term proposed to describe the chronic cutaneous insufficiency/fragility syndrome characterized by an extreme skin atrophy. Dermatoporosis is principally due to chronological aging and long-term and unprotected sun exposure, but it may also result from the chronic use of topical and systemic corticosteroids. We have recently proposed a membrane organelle, hyalurosome, composed of molecules involved in hyaluronate (HA) metabolism and cell signaling in the keratinocytes, such as principal HA receptor CD44, heparin-binding epidermal growth factor (HB-EGF), HB-EGF receptor erbB1 and HA synthase 3 (HAS3), which is functionally defective in dermatoporosis and may be a target for intervention. Several lines of evidence suggest that hyalurosome is located in keratinocyte filopodia, thin, actin-rich plasma membrane protrusions implicated in cell motility. We have recently shown that keratinocyte filopodia are downregulated by corticosteroids in vitro. Intermediate size HA fragments (HAFi) inhibited the downregulation of filopodia induced by corticosteroids. Topical HAFi prevented the skin atrophy induced by topical corticosteroids in mice without interfering with their anti-inflammatory effect. Topical treatment with HAFi 1% of atrophic forearm skin of dermatoporosis patients for 1 month resulted in a significant clinical improvement and induced the expression of hyalurosome molecules. Topical retinaldehyde (RAL) and HAFi showed a synergy in HA production and pro-HB-EGF expression in mouse skin and in the correction of skin atrophy in dermatoporosis patients. Uncovering the molecular mechanisms implicating hyalurosome seems to be crucial to better understand the pathogenesis of dermatoporosis and to develop new therapeutic strategies.

Topics: Adrenal Cortex Hormones; Aged; Aged, 80 and over; Aging; Animals; Atrophy; Cell Movement; Down-Regulation; Drug Synergism; Epidermis; Female; Glucuronosyltransferase; Heparin-binding EGF-like Growth Factor; Humans; Hyaluronan Synthases; Hyaluronic Acid; Intercellular Signaling Peptides and Proteins; Keratinocytes; Male; Mice; Middle Aged; Pseudopodia; Retinaldehyde; Skin; Skin Diseases

CD44 is a polymorphic proteoglycan and functions as the principal cell-surface receptor for hyaluronate (HA). Heparin-binding epidermal growth factor (HB-EGF) activation of keratinocyte erbB receptors has been proposed to mediate retinoid-induced epidermal hyperplasia. We have recently shown that intermediate size HA fragments (HAFi) reverse skin atrophy by a CD44-dependent mechanism.. Treatment of primary mouse keratinocyte cultures with retinaldehyde (RAL) resulted in the most significant increase in keratinocyte proliferation when compared with other retinoids, retinoic acid, retinol or retinoyl palmitate. RAL and HAFi showed a more significant increase in keratinocyte proliferation than RAL or HAFi alone. No proliferation with RAL was observed in CD44-/- keratinocytes. HA synthesis inhibitor, 4-methylumbelliferone inhibited the proliferative effect of RAL. HB-EGF, erbB1, and tissue inhibitor of MMP-3 blocking antibodies abrogated the RAL- or RAL- and HAFi-induced keratinocyte proliferation. Topical application of RAL or RAL and HAFi for 3 days caused a significant epidermal hyperplasia in the back skin of wild-type mice but not in CD44-/- mice. Topical RAL and HAFi increased epidermal CD44 expression, and the epidermal and dermal HA. RAL induced the expression of active HB-EGF and erbB1. However, treatment with RAL and HAFi showed a more significant increase in pro-HB-EGF when compared to RAL or HAFi treatments alone. We then topically applied RAL and HAFi twice a day to the forearm skin of elderly dermatoporosis patients. After 1 month of treatment, we observed a significant clinical improvement.. Our results indicate that (i) RAL-induced in vitro and in vivo keratinocyte proliferation is a CD44-dependent phenomenon and requires the presence of HA, HB-EGF, erbB1 and MMPs, (ii) RAL and HAFi show a synergy in vitro and in vivo in mouse skin, and (iii) the combination of RAL and HAFi seems to have an important therapeutic effect in dermatoporosis.

Topics: Adult; Aged; Aged, 80 and over; Animals; Atrophy; Epidermis; ErbB Receptors; Female; Humans; Hyaluronan Receptors; Hyaluronic Acid; Hyperplasia; Keratinocytes; Male; Mice; Mice, Inbred DBA; Mice, Transgenic; Middle Aged; Retinaldehyde; Skin Diseases

Topics: Chemical Phenomena; Chemistry; Humans; Isotretinoin; Neoplasms; Precancerous Conditions; Retinaldehyde; Skin Diseases; Tretinoin; Vitamin A; Vitamin A Deficiency