Infundibular protein and RNA microarray analyses from affected and clinically non-affected scalp in male androgenetic alopecia patients.

Non-invasive sample collection methods could facilitate clinical research on hair diseases. In an exploratory experimental study on six male volunteers with untreated androgenetic alopecia (AGA), Hamilton-Norwood stage IIIv-IV, skin surface and infundibular protein as well as RNA extracts from plucked hair follicles were analyzed from frontal skin, vertex and clinically unaffected occiput. Slightly increased levels of inflammatory markers were only found in AGA-affected scalp skin and infundibulum, not in RNA from plucked hair follicles.

2,3,7,8-Tetrachlorodibenzo-p-dioxin alters sebaceous gland cell differentiation in vitro.

Chloracne is a characteristic marker of intoxication by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or related compounds. Decreased lipogenesis is a prominent clinical sign in this disease. However, the activity of dioxins on human sebaceous glands is still unclear.

The role of neuropeptides in the multifactorial pathogenesis of acne vulgaris.

Background: Central or peripheral stress may induce the development of clinical inflammation in the pilosebaceous unit (PSU) leading to the development or to exacerbation of preexisting acne. The presence of a complete corticotropin-releasing hormone (CRH) system has been confirmed in human sebocytes in vitro. CRH is capable to induce lipid synthesis, steroidogenesis and interact with testosterone and growth hormone.

Comorbidities of hidradenitis suppurativa (acne inversa).

Comorbidities of hidradenitis suppurativa (acne inversa) were reviewed by extracting original and review publications included in MEDLINE, EMBASE and COCHRANE libraries using the terms "hidradenitis," "Verneuil" and "acne inversa." Follicular occlusion disorders, inflammatory bowel diseases, especially Crohn disease, spondylarthropathy, other hyperergic diseases, genetic keratin disorders associated with follicular occlusion and squamous cell carcinoma were the most common hidradenitis suppurativa comorbid diseases. A first classification of these major comorbidities and their possible genetic background reveals a list of chromosome loci and genes, which could be hidradenitis suppurativa candidates.

Interplay of IGF-I and 17beta-estradiol at age-specific levels in human sebocytes and fibroblasts in vitro.

In order to obtain greater insights into the molecular mechanisms accompanying hormonal aging the effects of growth hormone (GH), insulin-like growth factor-I (IGF-I), 17beta-estradiol, progesterone and dehydroepiandrosterone were tested as single agents in concentrations corresponding to 20- and 60-year-old females on human SZ95 sebocytes and fibroblasts. Cell proliferation and viability were measured by 4-methylumbelliferyl heptanoate and lactate dehydrogenase microassays, respectively, whereas lipid accumulation was documented via nile red microassay and fluorescence microscopy. mRNA and protein expression were evaluated via real-time RT-PCR and Western blotting or ELISA, accordingly.

IL-8 production and AP-1 transactivation induced by UVA in human keratinocytes: roles of D-alpha-tocopherol.

Identification of individual response-signal pathway induced by UVA-irradiation is necessary for understanding photo-biological and -pathological mechanisms with respect to the prevention of UV-irradiated skin damage and aging. Here, we investigated the role of D-alpha-tocopherol in the regulation of IL-8 production and AP-1 binding activity in UVA-irradiated human keratinocytes. UVA dramatically upregulated IL-8 mRNA expression and protein secretion and enhanced the AP-1-DNA binding activity.

GRO-alpha: a potential marker for cancer and aging silenced by RNA interference.

Age-regulated genes may serve as markers of aging, enabling assessment of physiological aging independent of chronological age. One gene with transcripts that increase in abundance with age in human organs, inter alia in epithelial skin cells, is the chemokine growth-regulated protein alpha (GRO-alpha). When chemokines, such as GRO-alpha, become disregulated so that they are chronically expressed, tissue damage, angiogenesis, and tumorigenesis can follow.

Nicotine and biochanin A, but not cigarette smoke, induce anti-inflammatory effects on keratinocytes and endothelial cells in patients with Behçet's disease.

During periods of smoking, patients with Behçet's disease have less oral aphthae than in abstinence. To elucidate this observation, human keratinocytes and dermal microvascular endothelial cells (HMEC-1) were incubated with serum of 20 patients with Behçet's disease and 20 healthy controls for 4 hours. Maximum non-toxic concentrations were determined and the cells were further treated with 6 microM nicotine, 3.

Enzymes involved in the biosynthesis of leukotriene B4 and prostaglandin E2 are active in sebaceous glands.

The expression of enzymes involved in leukotriene and prostaglandin signalling pathways, of interleukins 6 and 8 and of peroxisome proliferator-activated receptors in sebaceous glands of acne-involved facial skin was compared with those of non-involved skin of acne patients and of healthy individuals. Moreover, 5-lipoxygenase and leukotriene A(4) hydrolase were expressed at mRNA and protein levels in vivo and in SZ95 sebocytes in vitro (leukotriene A(4) hydrolase > 5-lipoxygenase), while 15-lipoxygenase-1 was only detected in cultured sebocytes. Cyclooxygenase-1 and cyclooxygenase-2 were also present.

Matrix metalloproteinases of epithelial origin in facial sebum of patients with acne and their regulation by isotretinoin.

Acne vulgaris is a skin disorder of the sebaceous follicles, involving hyperkeratinization and perifollicular inflammation. Matrix metalloproteinases (MMP) have a predominant role in inflammatory matrix remodeling and hyperproliferative skin disorders. We investigated the expression of MMP and tissue inhibitors of MMP (TIMP) in facial sebum specimens from acne patients, before and after treatment with isotretinoin.

Proliferation of human melanoma cells is under tight control of protein kinase C alpha.

Exponential proliferation of human melanoma cells has been associated with low levels of protein kinase C (PKC)-alpha. The aim of the present study was to investigate the functional relationship between PKC-alpha and melanoma cell proliferation. Treatment of human melanoma cells with the selective PKC inhibitor Ro-31-8220 resulted in a significant increase of cell proliferation as measured by (3)H-thymidine incorporation and a fluorometric microassay.

Differentiation and apoptosis in human immortalized sebocytes.

Increased cell volume, accumulation of lipid droplets in the cytoplasm, and nuclear degeneration are phenomena indicating terminal differentiation of human sebocytes followed by holocrine secretion and cell death. The molecular pathways of natural and induced sebocyte elimination are still unknown, however. In this study, SZ95 sebocytes were found to exhibit DNA fragmentation after a 6 h culture followed by increased lactate dehydrogenase release after 24 h, indicating cell damage.

Lack of protein kinase C (PKC)-beta and low PKC-alpha, -delta, -epsilon, and -zeta isozyme levels in proliferating human melanoma cells.

Protein kinase C (PKC), a calcium and phospholipid-dependent kinase, has been implicated in carcinogenesis of melanocytic cells. However, its role in melanoma cell growth remains controversial. We therefore investigated the growth dependence of PKC isozyme expression in human normal melanocytes and melanoma cells.