Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Sebaceous Glands”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources

Leptin modulates the effects of acyl CoA:diacylglycerol acyltransferase deficiency on murine fur and sebaceous glands.

Acyl CoA:diacylglycerol acyltransferase (DGAT) is a ubiquitously expressed enzyme that catalyzes the final reaction in the major pathways of triglyceride synthesis. Mice lacking DGAT1 (Dgat(-/-)) demonstrate significant changes in lipid metabolism in several tissues, including the skin. Here we report the effects of DGAT1 deficiency on fur and sebaceous glands. Adult Dgat(-/-) mice had dry fur and hair loss, which were associated with atrophic sebaceous glands and fur lipid abnormalities. As a result, Dgat(-/-) mice had impaired water repulsion and defective thermoregulation after water immersion. These phenotypes were mostly absent in Dgat(-/-) mice with leptin deficiency, indicating an unexpected role for leptin in modulating the skin phenotype. Our findings indicate that DGAT1 plays an important role in normal fur and sebaceous gland physiology and provide evidence that leptin modulates these processes in the skin.

Acyltransferases↗

Effects of benzoyl peroxide on lipogenesis in sebaceous glands using an animal model.

BACKGROUND: Benzoyl peroxide is the most widely used topical agent for acne since the 1960s. Concomitant treatment of benzoyl peroxide with oral, or topical antibiotics diminishes the multiplication of antibiotic-resistant strains of Propionibacteria acnes. Besides being antibacterial, the chemical also functions as a peeling agent, has comedolytic activity, reduces free fatty acid levels, and is touted to be sebosuppressive. OBJECTIVE: The purpose was to determine the ability of topically applied benzoyl peroxide to suppress lipogenesis of the sebaceous glands. METHODS: The data were obtained employing an animal model for human sebaceous glands, namely, the flank organs of female golden Syrian hamsters. RESULTS: Our results reveal no inhibition of lipogenesis in sebaceous glands by topical application of benzoyl peroxide. CONCLUSION: Despite many functions beneficial in acne therapy, benzoyl peroxide does not possess sebosuppressive capabilities. With the advent of water-soluble organic peroxides revealing similar antimicrobial activity to benzoyl peroxide, all therapeutic parameters (save for sebosuppression) will need to be assessed to weigh the benefits of these second-generation acne-fighting peroxides.

Acne Vulgaris↗

Topical spironolactone inhibits dihydrotestosterone receptors in human sebaceous glands: an autoradiographic study in subjects with acne vulgaris.

The interaction between spironolactone and dihydrotestosterone (DHT) receptors was evaluated with an autoradiographic technique. The inhibition of DHT receptors by spironolactone was found to be related to the decrease of tritiated DHT granules in the sebaceous glands of the treated site. 6 male patients affected by acne vulgaris entered the study. The acute study was performed by applying to 25 cm2 of the back a cream containing 5% spironolactone under occlusive dressing. The dosage of spironolactone applied was 4 mg/cm2 for 48 h. The long-term study was performed by applying the same amount to the entire back, without occlusion, twice daily for 1 month. Skin biopsies were taken at the end of the treatment, incubated with tritiated DHT and processed for autoradiography. Both the acute and the long-term study revealed a decrease of the autoradiographic granules in the treated site. This effect is related to the binding of spironolactone with dihydrotestosterone receptors in the sebaceous glands. Our study demonstrates that 5% topical spironolactone cream acts as an antiandrogen in human sebaceous glands, competing with DHT receptors and producing a decrease of labelled DHT. At the concentrations used the effect has been only local. No side-effects were recorded during both studies.

Acne Vulgaris↗

A possible specific receptor for 3-beta-androstanediol in the human sebaceous gland.

Dihydrotestosterone (DHT) does not seem to be the active specific metabolite of testosterone in hypertrophic sebaceous glands of subjects affected by male pattern baldness (MPB) and several results indicate that probably 3-beta-androstanediol (beta DIOL) could be an active form of testosterone in those glands. Cytosol and serum from several patients affected by MPB and subjected to hair autotransplantation, was incubated with both beta DIOL and 3-alpha-androstanediol (alpha DIOL). Binding patterns indicate that alpha DIOL binds to cytosolic proteins probably due to the contaminating sex hormone binding globulin (SHBG), whereas beta DIOL exhibits an atypical binding process in cytosol in the presence of high concentrations of non radioactive beta DIOL. This binding increases progressively up to 2 pmol/mg protein at the limit solubility conditions for the non radioactive steroid. This pattern is not observed in serum from the same patients, where the binding of beta DIOL is typically restricted to the SHBG. These results strongly suggest the existence of a specific beta DIOL-binding protein in the hypertrophic sebaceous glands and explain the lack of specific receptor for DHT in these tissues.

Alopecia↗

Cutaneous sebaceous gland carcinoma in the postauricular region.

Carcinomas of the sebaceous glands of the skin are uncommon. These tumours metastasize frequently. A case of cutaneous sebaceous carcinoma localized in the postauricular region is presented with its exceptional large size and very poor prognosis.

Adenocarcinoma↗

[Sebaceous gland carcinoma of the neck].

Extraocular sebaceous carcinoma is a rare skin neoplasm that resembles clinically pyogenic granuloma, hemangioma or squamous cell cancer. The clinical and histological findings are described. The differential diagnosis of common tumors of the face should include this rare malignancy.

Biopsy↗

Agents that cause enlargement of sebaceous glands in hairless mice. II. Ultraviolet radiation.

We have developed a murine model to measure the effects on sebaceous glands of ultraviolet (UV) radiation. Hairless mice were irradiated with Westinghouse FS-40 tubes filtered to attenuate the radiation below 290 nm. Emission was mainly in the UVB range (peak, 313nm). Single and multiple exposures were given with fractions or multiples of one minimal erythemal dose (MED). Biopsies, fixed for light microscopy, were stained with H & E. Under high power, sebocytes of 30 glands per specimen were counted and the means determined. A single exposure of 1 MED caused a significant increase in sebocyte count, as did thrice-weekly exposures to 0.5 MED for 3 weeks. One 3-MED exposure produced sebocyte necrosis, yet 30 exposures at 4 MED failed to ablate the glands. In both cases there was rebound enlargement which had not returned to control levels by the end of the studies (24-30 weeks). Prolonged irradiation produced maximum enlargement in a few weeks. Thus, in a manner similar to other skin components, the response of sebaceous glands to UV radiation is one of hyperplasia.

Animals↗

Mutations in gasdermin 3 cause aberrant differentiation of the hair follicle and sebaceous gland.

Defolliculated (Dfl) is a spontaneous mouse mutant with a hair-loss phenotype that includes altered sebaceous gland differentiation, short hair shafts, aberrant catagen stage of the hair cycle, and eventual loss of the hair follicle. Recently a similar mutant, finnegan (Fgn), with an identical phenotype was discovered during a phenotypic screen for mutations induced by chemical mutagenesis. The gene underlying the phenotype of both finnegan and defolliculated has been mapped to chromosome 11 and here we show that both mice harbor mutations in gasdermin 3 (Gsdm3), a gene of unknown function. Gsdm3(Dfl) is a B2 insertion near the 3' splice site of exon 7 and Gsdm3(Fgn) is a point mutation T278P. To investigate the role of the gasdermin gene family an antiserum was raised to a peptide highly homologous to all three mouse gasdermins and human gasdermin. Immunohistochemical analysis revealed that gasdermins are expressed specifically in cells at advanced stages of differentiation in the upper epidermis, the differentiating inner root sheath and hair shaft and in the most mature sebocytes of the sebaceous gland and preputial, meibomium, ceruminous gland, and anal glands. This expression pattern suggests a role for gasdermins in differentiation of the epidermis and its appendages.

Alopecia↗

Oxidative enzymes in the sebaceous glands of the domestic cat.

The distribution and activities of several oxidative enzymes in various regions of the sebaceous glands of the domestic cat have been studied. The results obtained emphasize the outstanding importance of NADP-linked dehydrogenases for lipogenesis during sebum production. In particular, the reactions for glucose-6-phosphate dehydrogenase were very strong. Among the NAD-linked dehydrogenases investigated, lactate dehydrogenase showed strong activity in the peripheral cells of the sebaceous gland. The reactions for cytochrome oxidase and succinate dehydrogenase were weaker.

Animals↗

Hyperplasia of sebaceous glands in a linear pattern of papules. Report of four cases.

Four cases of a clinically discernible hyperplasia of sebaceous glands in a linear pattern of papules were seen and studied at the Dominican Dermatological Institute in the past 3 years. The condition was found in three men and one woman and was characterized by a linear arrangement of papular lesions situated on the pre- and retroauricular regions, neck, and chin. The histologic features were stereotypic in all cases and consisted of hyperplasia of sebaceous glands.

Adolescent↗

Dermal cysts of the rhino mouse develop into unopened sebaceous glands.

The rhino mouse (hr(rh)hr(rh)) is a mutant strain characterized by a wrinkled and hairless skin with epidermal utriculi (pseudocomedones) and dermal cysts. The epidermal cysts have been extensively studied. The present work focused on the dermal cysts. By electron microscopy it was found that they appear on day 20 after birth and that they originate from a pool of undifferentiated epithelial cells of the deepest part of the initial follicular unit. Progressively, the number of cells in these islets increased and a central cavity was formed. Peripheral cells differentiated into sebocyte-like cells and outer root sheath cells. Staining with Oil Red O solution indicated accumulation of lipid material in the central cavity. The dermal cysts of the adult rhino mouse were isolated and purified in several steps including enzyme digestion, centrifugation, and separation on Nylex sieves. The integrity of the isolated cysts was confirmed by histology and electron microscopy. Study of their keratin polypeptide pattern by gel electrophoresis indicated that they express the mouse keratins 5, 14, 6 and 17. Neutral lipid analysis of the dermal cyst contents showed that they were mainly composed of cholesterol esters, wax esters, lipid fractions which migrate between triglycerides and cholesterol esters but very small amounts of triglycerides, cholesterol and ceramides. In conclusion, the present results demonstrate that dermal cysts of the rhino mouse have strong similarities with sebaceous glands and outer root sheath cells. These structures can easily be isolated and could therefore serve as a 'closed sebaceous gland' model to study the physiology or differentiation of the sebaceous gland, or the effects of pharmacological agents.

Animals↗

Ectopic sebaceous gland: a developmental anomaly.

We report the case of a 21-year-old white male with an ectopic sebaceous gland and duct located within the bulb of an anagen hair follicle. This is an incidental finding in one of two biopsies from his chin, performed as part of the workup for a recalcitrant perioral acneiform eruption. The embryogenesis and development of sebaceous glands in human scalp hair follicles are reviewed. To our knowledge, this is the first report of such a developmental anomaly.

Adult↗

Sebaceous gland secretion is a major physiologic route of vitamin E delivery to skin.

Skin plays an important part in the protection against oxidative stressors, such as ultraviolet radiation, ozone, and chemicals. This study was based on the observation that upper facial stratum corneum contained significantly higher levels of the antioxidant alpha-tocopherol than corresponding layers of arm stratum corneum. We hypothesized that the underlying mechanism involves sebaceous gland secretion of vitamin E. To test this, we examined in eight human volunteers: (i) stratum corneum levels and distribution profiles of vitamin E in sites with a different sebaceous gland density (arm versus cheek); (ii) whether vitamin E is a significant constituent of human sebum; and (iii) if there is a correlation between levels of vitamin E and squalene, a marker of sebum secretion, in skin surface lipids. Using standardized techniques for stratum corneum tape stripping and sebum collection, followed by high-performance liquid chromatography analysis of tocopherols and squalene, we found that: (i) the ratio of cheek versus upper arm alpha-tocopherol levels was 20 : 1 for the upper stratum corneum and decreased gradually with stratum corneum depth; (ii) vitamin E (alpha- and gamma-tocopherol forms) is a significant constituent of human sebum and is continuously secreted at cheek and forehead sites during a test period of 135 min; and (iii) vitamin E correlates well with levels of cosecreted squalene (r2 = 0.86, p < 0.001). In conclusion, sebaceous gland secretion is a relevant physiologic pathway for the delivery of vitamin E to upper layers of facial skin. This mechanism may serve to protect skin surface lipids and the upper stratum corneum from harmful oxidation.

Adult↗

Localization of herpes simplex virus type 1 in sebaceous glands of mice.

The distribution of HSV-1 during the development of zosteriform skin lesions in SCID mice was analyzed by immunofluorescence and electron microscopy. The virus initially appeared within certain keratinocytes, sometimes surrounded by keratinocytes whose surfaces were also positive for the antigens, in the lower epidermal layers including the hair follicles, and then extended upward to the entire epidermis and downward to the sebaceous glands 1-2 days later, when no macroscopic skin lesion was seen. The affected epidermal cells subsequently degenerated and lost their viral antigens within a day, when the zosteriform lesion then became evident. This was followed by a degeneration of the dermis. The sebaceous glands eventually degenerated in 10 days, but some glands in the necrotic skin areas preferentially retained HSV-1. The horizontal spread of the virus in the epidermis beyond the first invaded dermatome occurred much later. In mice passively immunized with specific immune serum, viral antigens were observed even 20 days after the infection in sebaceous glands in necrotized areas. Therefore, HSV-1 appears to spread first via the extracellular fluid among the keratinocytes after being shed from nerve endings, and then produces a successive degeneration of the affected keratinocytes which may prevent any further extension of horizontal viral spread. The pilosebaceous apparatus is possibly acting as a site not only for the replication of HSV-1 with a delayed cytopathic effect, but also as an area that is temporarily sheltered from host defense mechanisms.

Animals↗

[Circadian rhythm of proliferative processes in the sebaceous glands].

The proliferation process indices (such as the mitotic activity 0/00,labelled cell 0/00 and the amount of mitoses arrested by colchicine 0/00) were studied in two sebaceous glands of rats-the gland of the external auditory meatus and the tarsal sebaceous gland. It was established that the diurnal changes of the number of mitotically dividing cells and the DNA synthesizing cells could be presented as one-peak curves, the maximum falling on the night and morning hours and the minimum-on the day-time and evening. The average diurnal mitotic activity in terminal portions was 16, 3-1, 9 and the average amount of labelled cells was 76, 9-6, 1. In the excretory ducts they were 13, 0-1,6 and 65, 6-5, 4 respectively. The amount of C-mitoses in rats which were given colchicine was 75, 7-5,1 in the morning hours and 58, 1-4, 5% in the evening hours. It permitted to calculate the duration of mitoses which were equal to 1, 9 hour in the morning and 1,2 hour in day-time.

Animals↗

Inhibitory effects of 13-cis-retinoic acid on human sebaceous glands.

The effects of 13-cis-retinoic acid, which is clinically very effective in the treatment of severe acne, on sebaceous glands in humans was studied by means of histology, planimetry, and autoradiography. Histologically and planimetrically, one finds a marked decrease of size of sebaceous glands of up to 90% of the pretreatment values after 12 weeks of treatment. Additionally, the ratio of the so-called "differentiating cell pool (DCP)" vs. the so-called "undifferentiating cell pool (UCP)" changed from 2:1 to 1:7, probably indicating a disturbance of differentiation (lipid-production) of sebocytes. The labeling index of sebocytes also regressed significantly under therapy with 13-cis-retinoic acid.

Acne Vulgaris↗