scholarly journals Role of Androgen on Physiological Function of Pilosebaceous Unit

2021 ◽  
Vol 5 (3) ◽  
pp. 573-579
Author(s):  
Inda Astri Aryani ◽  
Cayadi Sidarta Antonius ◽  
Suroso Adi Nugroho ◽  
Nopriyati

The pilosebaceous unit is a sebaceous gland with hair follicles. One of the hormones that affects the pilosebaceous unit is androgen, a steroid hormone that plays an important role in the expression of the phenotype of men and women. Androgen consist of testosterone and dihydrotestosterone which are activated by androgen receptors. Androgen in the pilosebaceous unit affect sebum production and hair growth. Androgen receptors in the sebaceous glands are found on sebocytes and in hair follicles in the dermal papillae of hair follicles

2021 ◽  
Vol 5 (6) ◽  
pp. 545-551
Author(s):  
Inda Astri Aryani ◽  
Cayadi Sidarta Antonius ◽  
Suroso Adi Nugroho ◽  
Nopriyati

The pilosebaceous unit is a sebaceous gland with hair follicles. One of the hormones that affects the pilosebaceous unit is androgen, a steroid hormone that plays an important role in the expression of the phenotype of men and women. Androgen consist of testosterone and dihydrotestosterone which are activated by androgen receptors. Androgen in the pilosebaceous unit affect sebum production and hair growth. Androgen receptors in the sebaceous glands are found on sebocytes and in hair follicles in the dermal papillae of hair follicles


1992 ◽  
Vol 133 (3) ◽  
pp. 467-NP ◽  
Author(s):  
R. Choudhry ◽  
M. B. Hodgins ◽  
T. H. Van der Kwast ◽  
A. O. Brinkmann ◽  
W. J. A. Boersma

ABSTRACT A mouse monoclonal antibody against the N-terminal region of human androgen receptor (AR) was used to identify receptors by immunoperoxidase staining in frozen serial sections of skin from scalp, face, limb and genitalia of men and women aged 30–80 years. AR staining was restricted to cell nuclei. In sebaceous glands, AR were identified in basal and differentiating sebocytes. The percentage of receptor-positive basal sebocyte nuclei in the temple/forehead region was greater in males (65%) than in females (29%). AR staining was restricted to the cells of dermal papillae in anagen and telogen hair follicles. The percentage of dermal papillae containing AR was greater in males (58%) than in females (20%). The number of positively stained dermal papillae was lowest in female scalp skin. In 163 hair follicles sectioned, AR were absent from germinative matrix, outer root sheath (including the bulge region), inner root sheath, hair shaft and hair bulb, and from the capillaries present in some large dermal papillae. AR were present in pilosebaceous duct keratinocytes, suggesting that androgens may influence pilosebaceous duct keratinization. AR were also identified in interfollicular epidermal keratinocytes and dermal fibroblasts although, in both cell types, intensity and frequency of staining were greatest in genital skin. AR were identified in luminal epithelial cells of apocrine glands in genital skin and in certain cells of the secretory coils of eccrine sweat glands in all body sites. This study indicates that androgens regulate sebaceous gland and hair growth by acting upon two different types of target cells, the epithelial sebocytes of sebaceous glands and the mesenchymal cells of the hair follicle dermal papilla. AR staining in either cell type was not influenced by age in adults. The distribution of AR in human skin is consistent with the diverse effects of androgens on the structure and function of skin and its appendages. Journal of Endocrinology (1992) 133, 467–475


1973 ◽  
Vol 21 (2) ◽  
pp. 153 ◽  
Author(s):  
AG Lyne ◽  
DE Hollis

Development of horns has been studied in 20 foetuses ranging in age from 55 to 144 days of gestation, and in 16 lambs, ranging in age from birth to 42 days. Samples from one adult have also been examined. An increase in the thickness of the epidermis appears to be the first indication of horn development, recognizable in a 75-day-old male foetus and in an 84-day-old female foetus. Primary hair follicles develop in the horn region and produce emerging hairs, but these follicles later degenerate and disappear. The sweat glands and sebaceous glands formed in association with these follicles also degenerate, usually after hair growth has ceased. Fusion of primary follicles is a common feature in the horn growing skin, particularly before hair formation; a common connective tissue sheath surrounds the lower parts of these fused follicles. No secondary follicles are formed in the horn region but some branching of the primary follicles has been observed. By 118 days of gestation the epidermis in the horn region becomes greatly thickened, with very long dermal papillae which are well vascularized and innervated. Medulla-like columns of cells are formed above each dermal papilla and these cells keratinize later than the cells between the columns. These medullary cells remain in contact with each other longer than do the other cells of the horny sheath. Numerous arteriovenous anastomoses, which develop at two levels in the dermis of the horn region, are in continuity with capillaries which enter the dermal papillae of the epidermis. An outgrowth of bone from the frontal region of the skull, which later becomes the bony core of the horn, is first seen in a male foetus at 118 days. Acetylcholinesterase-positive branched cells (Langerhans cells), present in the lower part of the thick epidermis of developing horns, are not discernible in fully formed horns.


2020 ◽  
Vol 21 (16) ◽  
pp. 5672
Author(s):  
Kyung-Eun Ku ◽  
Nahyun Choi ◽  
Jong-Hyuk Sung

Rab27a/b are known to play an important role in the transport of melanosomes, with their knockout causing silvery gray hair. However, the relationship between Rab27a/b and hair growth is not well known. To evaluate the role of Rab27a/b in hair cycle, we investigated the expression of Rab27a/b during hair cycling and human outer root sheath (hORS) cells. The expression of Rab27a in ORS cells was mainly detected at the anagen, whereas expression of Rab27b in ORS, and epidermal cells was strongly expressed at the telogen. Additionally, Rab27a/b were expressed in the Golgi of hORS cells. To evaluate the role of Rab27a/b in hair growth, telogen-to-anagen transition animal and vibrissae hair follicles (HFs) organ culture models were assayed using Rab27a/b siRNAs. The knockdown of Rab27a or Rab27b suppressed or promoted hair growth, respectively. These results were also confirmed in human dermal papilla cells (hDPCs) and hORS cells, showing the opposite mitogenic effects. Moreover, Rab27b knockdown increased the expression levels of various growth factors in the hDPCs and hORS cells. Overall, the opposite temporal expression patterns during hair cycling and roles for hair growth of Rab27a/b suggested that Rab27a/b might regulate the hair cycle. Therefore, our study may provide a novel solution for the development of hair loss treatment by regulating Rab27a/b levels.


2018 ◽  
Vol 3 (10) ◽  
Author(s):  
Alexa Green ◽  
Felicia Jefferson

Everyone wants shine, softness, and hair strength, all key factors in having healthy hair. The purpose of this literature review is to provide information about healthy hair growth. Research states that the hair grows from follicles within the skin. Hair follicles are sacs where hair grows and where the sebaceous glands open. The follicles lined by cells derived from the epidermal. Keratin protects epithelial cells from damage and it makes up the outer layer of human skin. Even though there are many ways you can grow your hair, there are many ways you can lose your hair as well. This review paper also explains disorders that can cause hair loss.


2000 ◽  
Vol 149 (2) ◽  
pp. 503-520 ◽  
Author(s):  
Emmanuelle Charpentier ◽  
Robert M. Lavker ◽  
Elizabeth Acquista ◽  
Pamela Cowin

Plakoglobin regulates cell adhesion by providing a modulatable connection between both classical and desmosomal cadherins and their respective cytoskeletal linker proteins. Both plakoglobin and the related protein β-catenin are posttranscriptionally upregulated in response to Wnt-1 in cultured cells. Upregulation of β-catenin has been implicated in potentiating hyperproliferation and tumor formation. To investigate the role of plakoglobin in these functions we expressed a full-length (PG) and an NH2-terminally truncated form of plakoglobin (ΔN80PG) in mouse epidermis and hair follicles, tissues which undergo continuous and easily observed postnatal renewal and remodeling. Expression of these constructs results in stunted hair growth, a phenotype that has also been observed in transgenic mice expressing Wnt3 and Dvl2 (Millar et al. 1999). Hair follicles from PG and ΔN80PG mice show premature termination of the growth phase (anagen) of the hair cycle, an event that is regulated in part by FGF5 (Hebert et al. 1994). The proliferative rate of the epidermal cells was reduced and apoptotic changes, which are associated with entry into the regressive phase of the hair follicle cycle (catagen), occurred earlier than usual.


1980 ◽  
Vol 85 (2) ◽  
pp. 261-265 ◽  
Author(s):  
YEE CHU TOH

Sprague–Dawley rats were castrated either within 24 h of birth or at 4 weeks of age. Control animals were sham operated. Intact female rats were also included for comparison. Sebum production was assessed at 80 days of age by measuring the amount of skin-surface lipids that could be extracted with acetone and which had been produced during 2 days. The removal of the testes at birth reduced the activity of the sebaceous glands to a level more nearly approaching that seen in the female rats whereas castration at 4 weeks of age only partially decreased the rate of sebum secretion so that it was intermediate between the male and female rats. The weights of the pituitary gland, thyroid and adrenal glands increased after castration but there were no differences between rats castrated at birth and those castrated at 4 weeks of age except in the weight of the thyroid gland. It would appear that the role of the testes in the control of the activity of the sebaceous glands is a sequential event which has already started at birth.


Multiple nutritional, environmental and lifestyle factors can directly affect hair follicles, to weaken and make them sensitive to the action of androgens. Hair loss can be corrected and hair growth can be improved by addressing these non-androgenic factors. Patients having hair fall, thinning, loss of volume and poor growth can be precursors to androgenetic alopecia. Recent research has shown that androgens inhibit hair growth through release of Transforming Growth Factor (TGF) ß1. Further study of this mechanism reveals that generation of Reactive Oxygen Species (ROS) induced by androgens leads to release of TGF ß1 and use of ROS scavengers can block the release of TGF ß1, explaining beneficial role of antioxidants in hair growth. The binding of ROS to intracellular proteins also causes hair loss by altering the protein structure, changing their immune recognition and converting them to new antigens targeted by inflammatory and immune systems. Calorie restriction and individual micronutrient deficiencies lead to a new process of intracellular destruction or autophagy before cell apoptosis, which could explain cessation of hair growth. Telogen is not a resting phase but now defined as active conservation of follicles under unfavourable conditions. Thus any stress, trauma, metabolic change or insult causes telogen. Micronutrients zinc, copper, selenium maintains immunity, control inflammation and preserve antioxidant activity of the cells. Vitamins A, C, D have a role in phagocytosis and antibodies maintaining resistance. Vitamin D3 modulates the hair-inductive capacity of dermal papilla cells. Vitamin and micronutrient deficiencies are prevalent among all the population of the world. Nutritive value of the foods has reduced over the years by 30%. Endocrine Disrupting chemicals are creating further damage to the hormonal balance of the body. All these can be countered by use of antioxidants and a well-planned nutritional program which will ensure strengthening and regrowth of hair follicles, without the use of Finasteride.


2018 ◽  
Vol 28 (1) ◽  
pp. 13
Author(s):  
Hasbi Hasbi ◽  
Sri Gustina

<p class="00-6Abstrak2Wtz">Male fertility is affected by quantity and quality of sperm which controlled by androgens (testosterone and 5α-dihydrotestosterone) mediated by androgen receptors (AR). Androgen receptors belong to receptor group of steroid hormone and a group of ligand-activated nuclear receptor superfamily. This paper explains androgen hormone and its regulation in spermatogenesis to increase male fertility. Regulation of androgen hormone in spermatogenesis include initiation of spermatogenesis, proliferation and maturation of Sertoli cells, germ cell development, spermatogonia, meiosis, and spermiogenesis. The role of androgen hormone in regulation of spermatogenesis is influenced by AR, luteinizing hormone (LH), and follicle stimulating hormone (FSH) levels. Disruption of spermatogenesis will cause low male fertility. However, low concentrations of AR, LH and FSH could be enhanced by exogenous gonadotrophine releasing hormone (GnRH), LH, FSH, and testosterone to increase male fertility.</p>


2021 ◽  
Vol 7 (4) ◽  
pp. 363-366
Author(s):  
Kashish Tyagi ◽  
Sheilly Kapoor ◽  
Ishani Mohapatra ◽  
Komal Sharma

Alopecia areata, an auto-immune disorder characterised by the appearance of non-scarring bald patches affecting the hair bearing areas of the body, it can be extremely difficult to treat and has a poor prognosis despite many therapeutic options. Platelet Rich Plasma (PRP) has been previously used to treat variety of alopecia including alopecia areata. A 21-year old girl presented with asymptomatic loss of hair from the scalp for the last more than two years. On examination, there was diffuse loss of hair all over the scalp with few small, thin light-coloured hair in the occipital region. Histopathological examination showed miniaturised hair follicles surrounded by variable inflammatory lymphohistiocytic infiltrate with a marked reduction in terminal-vellus hair ratio to 1:1.The response to previous treatments was poor at the end of 1 year. A trial of PRP was given with no adjuvant treatment with a total of eight sessions of PRP. Dramatic response was noted after 2 sessions in the form of improvement in hair diameter and total volume. Resistant areas also started showing hair growth. There are a few studies assessing the role of PRP therapy in AA. First report to establish the efficacy of PRP as a treatment modality in AA, showed PRP therapy to be superior to TCA and Placebo in growing pigmented hair in AA patches. A case report with ophiasis type AA resistant to intralesional steroid injections showed excellent response to PRP therapy. Previous studies have demonstrated beneficial role of PRP therapy in cases of patchy alopecia areata, in contrast ours was a case of chronic diffuse AA. Inspite of many treatment modalities tried for more than a year, the response was unsatisfactory. PRP therapy yielded amazing results in the form of hair growth over resistant areas and overall increase in pigmented hair which were sustained at one and a half year follow up. Our case was unique in the way that excellent response to PRP treatment was noted (a) In a case of diffuse alopecia areata. (b) In a case non- responsive to standard modalities. (c) In a case with no other supportive treatment.


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