Steroidogenic enzymes, their related transcription factors and nuclear receptors in human sebaceous glands under normal and pathological conditions

Identification of meibomian gland testosterone metabolites produced by tissue-intrinsic intracrine deactivation activity

Intracrinology-wherein hormones are synthesized in the organ where they exert their effect without release into circulation-has been described. However, molecular mechanisms of hormone deactivation within intracrine tissue are still largely unknown. The meibomian glands in the eyelids produce oil (meibum) to the ocular surface to prevent dehydration (dry eye). Androgens are generated inside this gland and are crucial for its tissue-homeostasis. However, there is no data showing the presence of androgens in meibum, implying local conversion/deactivation into unknown metabolites. Here, we performed radioactive tracer studies in combination with pharmacological enzyme inhibition, followed by targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, and found three androgen metabolites-androstanedione, androsterone, and epiandrosterone-in mouse and human meibomian glands. Accounting for the enzymatic conversion, we show tissue-endogenous 3α/3β-ketosteroid reductase expression. We therefore reinforce the idea that androgens are metabolically inactivated within the glands. These metabolite markers may help to assess meibomian local androgen activity using meibum.

Steroidogenic Acute Regulatory Protein Is a Useful Marker for Sex-Cord-Stroma Tumors and Normal and Neoplastic Adrenocortical Tissue

CONTEXT.—

Steroidogenic acute regulatory (StAR) protein is a mitochondrial transport protein with a critical regulatory role for steroid hormone production. The tissue distribution of StAR expression is limited to few human normal tissues.

OBJECTIVE.—

To assess the diagnostic and prognostic value of StAR immunohistochemistry analysis.

DESIGN.—

A tissue microarray containing 19 202 samples from 152 different tumor types and subtypes and 608 samples of 76 different normal tissue types was analyzed by immunohistochemistry.

RESULT.—

StAR immunostaining occurred in 198 (1.2%) of the 17 135 analyzable tumors. StAR expression was observed in 27 of 152 tumor categories, 9 of which included at least 1 strongly positive case. The highest rate of StAR positivity occurred in Leydig cell tumors of the testis and the ovary (100%), steroid cell tumors of the ovary (100%), adrenocortical carcinomas (93%) and adenomas (87%), Sertoli-Leydig cell tumors (67%) and granulosa cell tumors of the ovary (56%), as well as seminomas (7%). Nineteen other tumor entities showed-a usually weak-StAR positivity in less than 6% of cases. A comparison with preexisting Melan-A (a melanocyte antigen) data revealed that StAR was more often positive in adrenocortical neoplasms and in Leydig cell tumors while StAR (but not Melan-A) was negative in Sertoli cell tumors.

CONCLUSIONS.—

Our data provide a comprehensive overview on the patterns of StAR immunostaining in human tumors and suggest a diagnostic utility of StAR immunohistochemistry for supporting a diagnosis of Leydig cell tumors or of normal or neoplastic adrenocortical tissue.

Sudachitin Alleviates Paraquat Instigated Testicular Toxicity in Albino Rats via Regulating Nrf-2/Keap-1, Inflammatory, Steroidogenic, and Histological Profile

Paraquat (PQ) is a noxious herbicide which adversely affects the vital organs including male reproductive system. Sudachitin (SCN) is a naturally occurring flavonoid that demonstrates a wide range of biological potentials. The current study was designed to investigate the alleviative potential of SCN to avert PQ-induced testicular toxicity in rats. Forty-eight male rats (Rattus norvegicus) were apportioned into four groups including control, PQ (5 mg/kg), PQ + SCN (5 mg/kg + 30 mg/kg), and SCN (30 mg/kg) only treated group. Our findings elucidated that PQ treatment reduced the expression of nuclear factor erythroid 2-related factor 2 (Nrf-2) and its antioxidant genes as well as the activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GSR) and glutathione peroxidase (GPx), while elevating the levels of reactive oxygen species (ROS), and malondialdehyde (MDA). Furthermore, PQ intoxication upregulated the expressions of Keap-1 while downregulating the expression of 3-beta hydroxysteroid dehydrogenase (3β-HSD), 17-beta hydroxysteroid dehydrogenase (17β-HSD), and steroidogenic acute regulatory protein (StAR). Moreover, sperm anomalies were increased following the exposure to PQ. Besides, PQ exposure decreased the levels of plasma testosterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) while increasing the levels of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), nuclear factor-kappa B (NF-κB), interleukin-1beta (IL-1β), and cyclooxygenase-2 (COX-2). Additionally, PQ treatment escalated the expressions of cysteinyl aspartate-specific proteases-3 (Caspase-3) and Bcl-2-associated X-protein (Bax) while downregulating the expressions of B-cell lymphoma-2 (Bcl-2). Furthermore, PQ exposure disrupted the normal architecture of testicular tissues. However, SCN treatment remarkably protected the testicular tissues via regulating the aforementioned disruptions owing to its antioxidant, anti-inflammatory, and androgenic potential.

Sebaceous immunobiology - skin homeostasis, pathophysiology, coordination of innate immunity and inflammatory response and disease associations

This review presents several aspects of the innovative concept of sebaceous immunobiology, which summarizes the numerous activities of the sebaceous gland including its classical physiological and pathophysiological tasks, namely sebum production and the development of seborrhea and acne. Sebaceous lipids, which represent 90% of the skin surface lipids in adolescents and adults, are markedly involved in the skin barrier function and perifollicular and dermal innate immune processes, leading to inflammatory skin diseases. Innovative experimental techniques using stem cell and sebocyte models have clarified the roles of distinct stem cells in sebaceous gland physiology and sebocyte function control mechanisms. The sebaceous gland represents an integral part of the pilosebaceous unit and its status is connected to hair follicle morphogenesis. Interestingly, professional inflammatory cells contribute to sebocyte differentiation and homeostasis, whereas the regulation of sebaceous gland function by immune cells is antigen-independent. Inflammation is involved in the very earliest differentiation changes of the pilosebaceous unit in acne. Sebocytes behave as potent immune regulators, integrating into the innate immune responses of the skin. Expressing inflammatory mediators, sebocytes also contribute to the polarization of cutaneous T cells towards the Th17 phenotype. In addition, the immune response of the perifollicular infiltrate depends on factors produced by the sebaceous glands, mostly sebaceous lipids. Human sebocytes in vitro express functional pattern recognition receptors, which are likely to interact with bacteria in acne pathogenesis. Sex steroids, peroxisome proliferator-activated receptor ligands, neuropeptides, endocannabinoids and a selective apoptotic process contribute to a complex regulation of sebocyte-induced immunological reaction in numerous acquired and congenital skin diseases, including hair diseases and atopic dermatitis.

Visualization of calcium channel blockers in human adrenal tissues and their possible effects on steroidogenesis in the patients with primary aldosteronism (PA)

Voltage-gated L-type calcium channel (CaV) isoforms are well known to play pivotal tissue-specific roles not only in vasoconstriction but also in adrenocortical steroidogenesis including aldosterone biosynthesis. Alpha-1C subunit calcium channel (CC) (CaV1.2) is the specific target of anti-hypertensive CC blockers (CCBs) and its Alpha-1D subunit (CaV1.3) regulates depolarization of cell membrane in aldosterone-producing cells. Direct effects of CCBs on aldosterone biosynthesis were previously postulated but their intra-adrenal distribution and effects on steroid production in primary aldosteronism (PA) patients have remained virtually unknown. In this study, frozen tissue specimens constituting tumor, adjacent adrenal gland and peri-adrenal adipose tissues of nine aldosterone-producing adenoma (APA) cases were examined for visualization of amlodipine and aldosterone themselves using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Liquid chromatography-mass spectrometry (LC-MS) analysis was also performed to quantify amlodipine and 17 adrenal steroids in those cases above and compared the findings with immunohistochemical analysis of steroidogenic enzymes and calcium channels (CaV1.2 and CaV1.3). Effects of amlodipine on mRNA level of aldosterone biosynthetic enzymes were also explored using human adrenocortical carcinoma cell line (H295R). Amlodipine-specific peak (m/z 407.1 > 318.1) was detected only in amlodipine treated cases. Accumulation of amlodipine was marked in adrenal cortex compared to peri-adrenal adipose tissues but not significantly different between APA tumors and adjacent adrenal glands, which was subsequently confirmed by LC-MS quantification. Intra-adrenal distribution of amlodipine was generally consistent with that of CCs. In addition, quantitative steroid profiles using LC-MS and in vitro study demonstrated the lower HSD3B activities in amlodipine treated cases. Immunoreactivity of CaV1.2 and HSD3B2 were also correlated. We report the first demonstration of specific visualization of amlodipine in human adrenal tissues by MALDI-MSI. Marked amlodipine accumulation in the adrenal glands suggested its direct effects on steroidogenesis in PA patients, possibly targeting on CaV1.2 and suppressing HSD3B activity.

Interleukins 4 and 13 drive lipid abnormalities in skin cells through regulation of sex steroid hormone synthesis

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by skin dryness, inflammation, and itch. A major hallmark of AD is an elevation of the immune cytokines IL-4 and IL-13. These cytokines lead to skin barrier disruption and lipid abnormalities in AD, yet the underlying mechanisms are unclear. Sebaceous glands are specialized sebum-producing epithelial cells that promote skin barrier function by releasing lipids and antimicrobial proteins to the skin surface. Here, we show that in AD, IL-4 and IL-13 stimulate the expression of 3β-hydroxysteroid dehydrogenase 1 (HSD3B1), a key rate-limiting enzyme in sex steroid hormone synthesis, predominantly expressed by sebaceous glands in human skin. HSD3B1 enhances androgen production in sebocytes, and IL-4 and IL-13 drive lipid abnormalities in human sebocytes and keratinocytes through HSD3B1. Consistent with our findings in cells, HSD3B1 expression is elevated in the skin of AD patients and can be restored by treatment with the IL-4Rα monoclonal antibody, Dupilumab. Androgens are also elevated in a mouse model of AD, though the mechanism in mice remains unclear. Our findings illuminate a connection between type 2 immunity and sex steroid hormone synthesis in the skin and suggest that abnormalities in sex steroid hormone synthesis may underlie the disrupted skin barrier in AD. Furthermore, targeting sex steroid hormone synthesis pathways may be a therapeutic avenue to restoring normal skin barrier function in AD patients.

The relationship among androgens, insulin resistance and ghrelin polymorphisms in post-adolescent male patients with severe acne vulgaris

INTRODUCTION

Ghrelin has anti-inflammatory and immunomodulatory activities. Data about the role of ghrelin and ghrelin polymorphisms in the development of acne vulgaris in post-adolescent male patients are limited.

AIM

To evaluate the role of serum androgens, insulin resistance, ghrelin and ghrelin polymorphisms in severe acne vulgaris.

MATERIAL AND METHODS

Thirty-five post-adolescent male patients with a mean age of 28.0 ±5.4 years and 33 age-and BMI-matched controls were enrolled. Serum androgens, lipids, insulin sensitivity parameters and ghrelin levels were determined. The PCR method was used for GHRL polymorphisms (rs27647, rs696217 and rs34911341 genotypes).

RESULTS

Patients had similar anthropometric measures to controls, except a significantly higher WHR in patients (0.92 ±0.06 vs. 0.86 ±0.08, p < 0.05). Also, FPG, HOMA-IR values, lipid profile and serum androgen levels were similar. Interestingly, patients had significantly lower ghrelin levels than controls (4.5 ±5.8 vs. 101.2 ±86.5 pg/ml, p < 0.001). The frequencies of rs696217 and rs34911341 genotypes were similar whereas the distribution of rs27647 alleles was significantly different between the groups (p < 0.05). GA and GG genotypes of GHRL rs27647 polymorphism indicated an increased risk of developing acne vulgaris (OR = 11.156, 95% CI: 2.864-43.464, OR = 5.312, 95% CI: 1.269-22.244, respectively; p < 0.05). Patients with rs27647-AA polymorphism had significantly lower GAGS scores than other groups (AA genotype 6.7 ±14.1 vs. GA genotype 24.6 ±15.7 and GG genotype 19.4 ±17.9, p < 0.001). None of the polymorphisms had a significant effect on metabolic parameters, insulin sensitivity and serum ghrelin levels.

CONCLUSIONS

Decreased ghrelin levels and GA and GG genotypes of GHRL gene rs27647 polymorphism may have a role in the pathogenesis of acne vulgaris.

Inhibition of Luman/CREB3 expression leads to the upregulation of testosterone synthesis in mouse Leydig cells

Luman, also known as cAMP-response element-binding protein 3, is an endoplasmic reticulum stress-related protein that has been identified as a novel transcriptional coregulator of a variety of nuclear receptors. Herein, immunohistochemistry results showed that Luman was specifically expressed in mouse Leydig cells in an age-dependent increase manner, from prepuberty to sexual maturation. Luman was not detected in Sertoli cells within the seminiferous tubules at any developmental period. The immunofluorescent experiment indicated that Luman was mainly located within the cytoplasm of murine Leydig tumor cells (MLTC-1) and primary Leydig cells (PLCs). To investigate the physiological function of Luman, experiments were conducted to examine the consequences of short hairpin RNA- and small interfering RNA-mediated Luman knock-down in MLTC-1 and PLCs, respectively. Luman knock-down significantly upregulated the expression of steroidogenic acute regulatory, cytochrome P450 cholesterol side-chain cleavage enzymes, 3β-hydroxysteroid dehydrogenase, and 17-α-hydroxylase/C17-20 lyase in MLTC-1 cells and PLCs. Luman knock-down caused an increase in human chorionic gonadotropin-stimulated testosterone production in vitro and in vivo. The nuclear receptors SF-1 and Nur-77 were significantly increased upon Luman knock-down in MLTC-1. By contrast, the level of the nuclear receptor SHP decreased. Luciferase reporter assay results demonstrated that Luman knock-down upregulated the activity of SF-1 and Nur-77 promoters. These data suggested that Luman expressed in mouse Leydig cells in an age-dependent increase manner. Luman knock-down upregulated the activity of SF-1 and Nur-77 promoters, which lead to the increase of testosterone synthesis and steroidogenesis genes expression. In conclusion, these findings provide us with new insights into the role Luman played in male reproduction.

Prenatal Androgenization of Ewes as a Model of Hirsutism in Polycystic Ovary Syndrome

The main clinical feature associated with hyperandrogenism in polycystic ovary syndrome (PCOS) in humans is hirsutism, where hair increases its length, pigmentation, and particularly its diameter. Currently, it is not known whether PCOS animal models also exhibit changes in the hair. Therefore, the aim of this study was to explore the wool characteristics in sheep prenatally androgenized (PA) with testosterone propionate. After 4 and 13 months of life, wool was collected from the top of the shoulder of both females and males (both androgenized and controls). The offspring sheep were followed for up to 19 months of life to evaluate testosterone and androstenedione serum levels by ultra-high-performance liquid chromatography-tandem mass spectrometry, determine insulin and glucose response to intravenous glucose tolerance test, and address estrus cyclicity during the second breeding season. PA male animals showed a reduction in wool fiber diameter at 4 months of age compared with controls (P = 0.02) but not at 13 months, whereas PA females showed increased hair diameter at 13 months (P = 0.002), with no difference at 4 months. No substantial changes in other hair parameters (length, color, and medullation) were identified. In addition, increased levels of serum testosterone were observed in PA female sheep compared with controls at 12 months (P = 0.03). Our results indicate for the first time, to our knowledge, that changes in wool fiber diameter observed in PA ewes replicate, at the translational level, the increase in hair diameter in hirsute women with PCOS.

Virilism and Ectopic Expression of HSD17B5 in Mature Cystic Teratoma

Mature cystic teratoma (MCT) is rarely involved in the overproduction of steroid hormones in contrast to sex cord stromal tumors. A 31-year-old woman visited our hospital with hirsutism, hoarseness, and hair loss from the scalp. Serum testosterone and free-testosterone levels were 7.3 ng/ml and 2.3 pg/ml, respectively, which were markedly in excess of the age adjusted female standard levels. Basal blood levels of steroid hormones and serum levels of 17-hydroxyprogesterone at 1 h after intravenous injection of adrenocorticotropic hormone demonstrated that 21-hydroxylase deficiency was not the underlying cause of her virilization. A subsequent chromosomal test with G-banding revealed a karyotype of 46XX. Magnetic resonance imaging revealed a mass in the left ovary, which was subsequently diagnosed as MCT. Detailed pathological analysis of the tumor indicated that it was comprised of skin components, sweat glands, with hair and fat texture, glandular epithelium and fibrous connective tissue, consistent with the characteristic composition of MCT. Immunohistochemical analysis demonstrated marked immunoreactivity of 17beta-hydroxysteroid dehydrogenase (HSD17B5), an enzyme that can convert androstenedione to testosterone. Following surgical removal of the tumor, testosterone and free testosterone levels were markedly decreased (0.3 ng/ml and 0.4 pg/ml, respectively) and other symptoms abated. In conclusion, this is the first report of an ovarian MCT associated with clinical virilization caused by the ectopic production of testosterone possibly because of an overexpression of intratumoral HSD17B5.

Estrogen receptor β in Merkel cell carcinoma: its possible roles in pathogenesis

Sex steroids have been postulated to influence skin development and functions as well as its pathogenesis. MCC occurs in both sexes; however, the specific differences in pathogenesis among sexes have yet to be conclusively defined. The detailed status of sex steroid receptors (AR, PRA and PRB, and ERα, ERβ) are also unknown in MCC patients. We first immunolocalized sex steroid receptors and compared the results with immunolocalization of relevant transcription factors including SOX2, FOXA1, and Bcl-2 and Ki-67 in 18 cases of MCCs. AR, PRA, PRB, ERα, ERβ, Bcl-2, SOX2, and FOXA1 immunoreactivity was evaluated by using the modified H score method, and Ki-67 was quantified using labeling index. ERβ immunoreactivity was markedly present in all the cases of MCC examined, with relatively weak immunoreactivity of ERα, AR, PRA, and PRB. The status of ERβ immunoreactivity was also significantly correlated with Ki-67 labeling index and Bcl-2 score. These results demonstrated that ERβ could be associated with regulation of both cell proliferation and apoptosis in MCCs.

On the role of skin in the regulation of local and systemic steroidogenic activities

The mammalian skin is a heterogeneous organ/tissue covering our body, showing regional variations and endowed with neuroendocrine activities. The latter is represented by its ability to produce and respond to neurotransmitters, neuropeptides, hormones and neurohormones, of which expression and phenotypic activities can be modified by ultraviolet radiation, chemical and physical factors, as well as by cytokines. The neuroendocrine contribution to the responses of skin to stress is served, in part, by local synthesis of all elements of the hypothalamo-pituitary-adrenal axis. Skin with subcutis can also be classified as a steroidogenic tissue because it expresses the enzyme, CYP11A1, which initiates steroid synthesis by converting cholesterol to pregnenolone, as in other steroidogenic tissues. Pregnenolone, or steroidal precursors from the circulation, are further transformed in the skin to corticosteroids or sex hormones. Furthermore, in the skin CYP11A1 acts on 7-dehydrocholesterol with production of 7-dehydropregnolone, which can be further metabolized to other Δ7steroids, which after exposure to UVB undergo photochemical transformation to vitamin D like compounds with a short side chain. Vitamin D and lumisterol, produced in the skin after exposure to UVB, are also metabolized by CYP11A1 to several hydroxyderivatives. Vitamin D hydroxyderivatives generated by action of CYP11A1 are biologically active and are subject to further hydroxylations by CYP27B1, CYP27A1 and CP24A. Establishment of which intermediates are produced in the epidermis in vivo and whether they circulate on the systemic level represent a future research challenge. In summary, skin is a neuroendocrine organ endowed with steroid/secosteroidogenic activities.

3β-Hydroxysteroid dehydrogenase isoforms in human aldosterone-producing adenoma

It has become important to evaluate the possible involvement of 3β-hydroxysteroid dehydrogenase type 1 (HSD3B1) and 2 (HSD3B2) isoforms in aldosterone-producing adenoma (APA). In this study, we studied 67 and 100 APA cases using real-time quantitative PCR (qPCR) and immunohistochemistry, respectively. Results of qPCR analysis demonstrated that HSD3B2 mRNA was significantly more abundant than HSD3B1 mRNA (P < 0.0001), but only HSD3B1 mRNA significantly correlated with CYP11B2 (aldosterone synthase) mRNA (P <0.0001) and plasma aldosterone concentration (PAC) of the patients (P <0.0001). Results of immunohistochemistry subsequently revealed that HSD3B2 immunoreactivity was detected in the great majority of APA but a significant correlation was also detected between HSD3B1 and CYP11B2 (P <0.0001). In KCNJ5 mutated APA, CYP11B2 mRNA (P <0.0001) and HSD3B1 mRNA (P = 0.011) were significantly higher than those of wild type APA. These results suggest that HSD3B1 is involved in aldosterone production, despite its lower levels of expression compared with HSD3B2, and also possibly associated with KCNJ5 mutation in APA.