Female pattern hair loss, sebum excretion and the end-organ response to androgens

BACKGROUND: Although female pattern hair loss can be a feature of hyperandrogenism, many women with hair loss show no clinical or biochemical features of androgen excess. It is possible that hair loss in nonhyperandrogenic women is due to a high level of response to androgens by scalp hair follicles. In this study we explored this idea using sebum excretion as a marker of the cutaneous end-organ response to androgens. OBJECTIVES: To test the hypothesis that hair loss in nonhyperandrogenic women is due to an increased cutaneous end-organ response to androgens. METHODS: We studied 100 women, 41 with female pattern hair loss (without hirsutism), 29 with hirsutism (with and without scalp hair loss) and 30 subjects without hair problems. We measured hair density on the frontal scalp, forehead sebum excretion, serum free androgen index (FAI), and body mass index (BMI). RESULTS: The mean FAI was significantly raised in hirsute women compared with nonhirsute women (P < 0.001), but there was no difference in FAI levels between nonhirsute women with and without hair loss. The mean BMI was also significantly elevated in hirsute women (P < 0.01) but there was no difference in BMI between nonhirsute women with and without hair loss. The mean sebum excretion was higher in hirsute women than nonhirsute women but the difference was not statistically significant. There was no difference in sebum excretion between nonhirsute women with and without hair loss. There was no correlation between hair density and sebum excretion. CONCLUSIONS: Our results show that sebum excretion is not elevated in women with female pattern hair loss. This may indicate that different androgen-response pathways operate in controlling hair growth and sebum excretion. The alternative explanation is that nonandrogenic mechanisms are involved in mediating hair loss in some women.     

Evaluation of the effects of 10% and 30% gluconolactone chemical peel on sebum,pH, and TEWL

Background

Gluconolactone (GLA) exhibits antioxidant and moisturizing effects. It also presents soothing effects, protects elastin fibers from UV-induced degradation, and improves the function of the skin barrier.

Aims

Evaluation of skin parameters such as pH, transepidermal water loss (TEWL), sebum levels before, during, and after a series of applications of 10% and 30% GLA chemical peel in a split-face model.

Materials and Methods

The study involved 16 female subjects. Three split-face procedures were performed using two concentrations of GLA solution applied on two sides of the face. The skin parameters were measured before treatments and 7 days after the last procedure at four measurement sites on either side of the face, that is, on the forehead, around the eye, on the cheek, and on the nose wing.

Results

Measurement of sebum demonstrated some statistically significant changes between sebum levels in the cheeks after a series of treatments. The pH measurement showed that the pH value was reduced after each treatment at all measurement points. The level of TEWL after treatments was significantly lower around the eyes, on the left forehead, and on the right cheek. There were no significant differences between the use of different concentrations of the GLA solution.

Conclusions

The results of the study show that GLA has a significant influence on lowering skin pH and TEWL. GLA also has seboregulatory properties.     

A review of the role of sebum in the mechanism of acne pathogenesis

Acne is one of the most common skin disorders, and its occurrence is closely related to many factors, including sebum secretion, hormone levels, bacterial infection, and inflammatory reactions. Among these, changes in sebum secretion are believed to be one important factor of acne. Increased sebum secretion can induce acne occurrence, and increasing evidence indicates sebum component changes are also strongly related to acne occurrence. Recently, developments in lipidomics have provided effective lipid analysis methods. These can help elucidate the effects of different types of sebum on acne occurrence and provide a theoretical basis for research on the mechanisms of acne pathogenesis and treatment.     

我国正常人皮肤表面皮脂和水分含量的研究

目的：了解我国不同年龄、不同性别正常人皮肤角质层含水量、皮肤表面皮脂含量及皮肤皮脂的分泌速度。方法：利用皮肤表面皮脂测量仪和皮肤水分含量测量仪对我国北方325名正常人的前额及前臂屈侧皮肤皮脂量和皮肤含水量进行测量。结果：12岁以前,男女前额皮脂量无差异;13岁以后,男性前额的皮脂量明显高于女性。除36～50岁年龄组外,女性前额的皮脂分泌快于男性。男女前臂的皮脂量无差异。除男性13～35岁组的前额皮肤含水量高于女性外,其他各年龄组各部位男、女皮肤含水量无显著差别。13～35岁组男、女性前额的含水量均高于前臂。其他各年龄组前额和前臂皮肤含水量无明显部位差异。13-35岁组男性前额皮肤含水量最高。结论：正常人皮肤表面含水量和皮脂含量因性别、年龄和部位的不同而有差异。     

In vitro and in vivo study of the efficacy of a new sebum control essence

Background

People with oily skin often suffer from skin problems such as oily face, blackheads, acne, and enlarged pores. It is necessary to regulate oily skin with skin care products.

Aims

To develop an effective sebum control essence to reduce oiliness of skin.

Methods

The composition of the essence was designed in consideration of different oil control mechanism targets. The skin irritation was assessed in 30 volunteers by a single application close patch test. The efficacy of the essence was evaluated by in vitro experiment, short- and long-term clinical trials with over 60 volunteers.

Results

The results of both in vitro and clinical trials showed that the essence had significant oil control and moisturizing effect, the skin oil content decreased by 21.8% within 8 h and 30.05% after 28 days, which indicated that the essence could achieve rapid and persistent sebum control efficacy. In addition, the essence could relieve the problems of enlarged pores, blackheads and whiteheads in long-term use.

Conclusions

The essence developed in this study can alleviate the problems of oily skin from many aspects, and achieve an excellent effect in oily skin regulation. It is suitable for a daily application in oily skin regulation.     

Influence of oral metronidazole on the endocrine milieu and sebum excretion rate.

As part of a study of the mechanism of metronidazole's efficacy in the treatment of acne and rosacea, its effects on the endocrine milieu and sebum excretion rate were assessed. Thirteen healthy males received oral metronidazole treatment (500 mg/day) for 4 weeks. Serum sex hormone levels were determined in all 13 subjects and the sebum excretion rate was determined in seven of them, before and after treatment. We measured serum levels of estrone (E1), estradiol (E2), total testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), dehydroepiandrosterone sulfate (DHEA-S), and sex hormone-binding globulin (SHBG). There were no significant changes in E1, T, FT, DHT, or SHBG levels, but E2 and DHEA-S levels decreased significantly after treatment. In all seven subjects in whom the sebum excretion rates were determined, the amount of facial skin surface lipids decreased significantly after treatment. These results suggest that metronidazole exerts its clinical effects through suppressing the sebum excretion by a mechanism other than anti-androgenic action.     

头皮屑和头皮脂溢性皮炎患者头皮脂类水平及马拉色菌数量的检测

目的:测定有头皮屑及头皮脂溢性皮炎患者与正常受试者头皮表面脂类水平及马拉色菌数量的差异。方法:使用sebumeter于洗发后连续4天测量受试者额、顶、枕部头皮皮脂,并于第4天真菌镜检马拉色菌,记录马拉色菌数量。结果:有头皮屑及头皮脂溢性皮炎组与正常对照组相比,马拉色菌数量显著增高,具有统计学意义(P<0.05)。头皮脂溢性皮炎组较头皮屑组的马拉色菌数量显著增高,具有统计学意义(P<0.05)。在头皮屑及头皮脂溢性皮炎组中,随着炎症程度加重,检出的马拉色菌孢子数增多。结论:马拉色菌感染可能与头皮屑多和脂溢性皮炎有关。     

Moisturizing and antisebum effect of cosmetic application on facial skin

Background Water content of the stratum corneum and skin surface lipids are important factors in the appearance and function of skin. High water content and low sebum secretion are considered main features of fair skin. Aim This paper aims to study the change of skin physiological parameters after cosmetic application. Methods The skin water content, transepidermal water loss, and skin sebum secretion on different regions of the facial skin before and after the cosmetic application were measured using Corneometer, Tewameter, and Sebumeter, respectively. Results The cosmetics kept higher water content and lower transepidermal water loss, at the same time lower sebum secretion 4  and 8 h after the cosmetic application, compared with those before it. The situation was maintained in the following 3‐week continuous use of the cosmetics. Conclusion The cosmetic application on human facial skin could provide some moisturizing effect and at the same time some antisebum effect according to different regions on facial skin, which favored the maintenance of good skin physiological function after applying skin care products.     

Regional and seasonal variations in facial sebum secretions: a proposal for the definition of combination skin type

BACKGROUND/AIMS: Facial sebum secretions are known to change under various circumstances. Facial skin types have been categorized as oily, normal, dry, and combination types. However, these have been evaluated subjectively by individuals to date, and no objective accepted standard measurement method exists. The combination skin type is most common, but its definition is vaguer than the definitions of the other skin types. METHODS: We measured facial sebum secretions with Sebumeter. Sebum secretions were measured at five sites of the face seasonally for a year, in the same volunteers. Using the data obtained we developed a set of rules to define the combination skin type. RESULTS: Regional differences in sebum secretion were confirmed. Sebum secretions on forehead, nose, and chin were higher than on both cheeks. Summer was found to be the highest sebum-secreting season, and seasonal variations were found in the T- and U-zones. A mismatch of skin type in the T- and U-zones in more than two seasons appears to be close to subjective ratings of what is described as the 'combination' skin type. CONCLUSION: We showed that the face shows definitive regional and seasonal variations in sebum secretion. To define the combination skin type, seasonal variations in sebum secretion should be considered in addition to regional variations.     

Transepidermal water loss, temperature and sebum levels on women's facial skin follow characteristic patterns

Background/aims: The aim of this study was to compare the biophysical properties of different facial zones. Methods: We investigated transepidermal water loss (TEWL), skin temperature and sebum casual level (CL) on 90 adjacent test sites distributed on the forehead, cheeks and chin of five women. Results: All three parameters showed a symmetrical distribution around the facial median line. Only minor variations of individual values were found within the forehead and the chin areas. In contrast, the cheeks exhibited a distinct gradient with highest values in the paranasal zones and lowest on the cheek bones for all of the three parameters. The mean values on both cheeks of a given individual were nearly identical, and the patterns within the two cheeks were superimposable. Both CL and skin temperature distributions pointed out a “T‐zone” with highest values on the forehead, on the chin and on the median part of the cheek. Conclusions: Our data demonstrate that biophysical skin properties differ considerably between different facial areas but that they follow a characteristic distribution.     

Degreasing method for the seborrheic areas with respect to regaining sebum excretion rate to casual level

Background/aims: Sebum excreted from the seborrheic glands keeps the skin surface subtle and moist. Before determining the activity of seborrheic glands, the skin surface must be degreased to remove contamination but without provoking sebum excretion. The purpose of this study was to set up a standardised degreasing procedure for various seborrheic areas in different skin types. The method will take day‐to‐day variations into account with respect to the kinetics of refatting. Methods: The Sebumeter^® from Courage+Khazaka is used to quantify the sebum excretion. Day‐to‐day variations were measured on the forehead in groups of 12 volunteers on 2 consecutive days. The degreasing procedure was investigated by individual cleaning with alcohol compared to washing with a mild detergent followed by wipes with alcohol on the forehead. The degree of refatting was monitored until 3 h after defatting on seborrheic areas: the forehead, cheek, nose, chin and upper back. Results: There was no statistical significant difference in the variation from day to day (P<0.05), although a change in the individual skin types was observed. An individual difference in the number of alcoholic wipes needed to degrease the forehead was seen. Washing followed by several repetitions of alcoholic wipes was not sufficient for the forehead, chin and nose (P>0.05). For the cheek and upper back, it was sufficient to wash with soap (P<0.05). The time from degreasing the skin until the sebum output reached the casual level was 2 h (P>0.05). The area under the curve (AUC) indicates that individual skin types return to casual level after defatting. Conclusion: There was no statistically significant day‐to‐day variation using the Sebumeter^®. We ended up with different degreasing procedures in different seborrheic areas. Washing gently with a detergent solution and then performing three wipes with alcohol was optimal for degreasing the forehead, nose and chin. For the cheek and upper back, it was sufficient to use a mild soap. Casual level was reached after 2 h in all seborrheic areas, irrespective of level of oiliness.     

Comparative study of skin sebum and elasticity level in patients with sulfur mustard‐induced dermatitis and healthy controls

Background: Sulfur mustard (SM) – a chemical agent – has both acute and chronic effects on skin. Xerosis, which is deemed to be due to the damage of hydrolipidic barrier of the skin, is the most common complaint of veterans exposed to the chemical. This study was designed to evaluate skin sebum and elasticity in veterans with a history of SM contact. Methods: Three hundred and ten subjects were enrolled in this study and were divided into four groups: SM‐exposed patients with current skin lesions (n=87); SM‐exposed patients without skin lesions (n=71); patients with dermatitis (n=78); and normal controls (n=74). The skin sebum and elasticity were measured in four areas (forehead, suprasternal, palm and back of the hands) using a Sebumeter and a Reviscometer. Results: Skin sebum was higher in participants who presented with dermatitis and had history of contact with SM than others; the difference was only statistically significant on the forehead. There was no significant difference in the skin elasticity between the four groups. Conclusion: While SM may increase skin sebum in long term, there is no evidence that it has a substantial effect on skin elasticity.