Monocyte/macrophage androgen receptor suppresses cutaneous wound healing in mice by enhancing local TNF-alpha expression

The number and localization of CD68+ and CD163+ macrophages in different stages of cutaneous melanoma

The role of tumor-associated macrophages (TAMs) in cutaneous melanoma is controversial. TAMs include immunogenic and immunosuppressive subtypes, and have distinct functions according to their microanatomical localization. Our aim was to investigate TAMs in benign, premalignant, and malignant melanocytic lesions to determine possible associations with tumor progression and clinicopathological characteristics. In total, 184 tissue samples, including benign and dysplastic nevi, in-situ melanomas, superficial (Breslow's depth <1 mm), and deep (Breslow's depth >4 mm) invasive melanomas and lymph node metastases, were analyzed for macrophage content. Samples were stained immunohistochemically for CD68 and CD163, representing all TAMs and M2-macrophages, respectively. Macrophages were counted by hotspot analysis, and assessed semiquantitatively from the tumor cell nests and stromal component of malignant cases. CD68+ and CD163+ TAMs were more abundant in invasive melanomas compared with benign nevi. The proportion of TAMs in the tumor nests was higher in deep melanomas and lymph node metastases compared with superficially invasive melanomas. High amounts of CD68+ macrophages in tumor cell nests were associated with recurrence, whereas low CD163+ macrophage proportion in tumor stroma was associated with recurrence and in primary melanomas also with poor overall survival. TAMs seem to promote tumor progression in cutaneous melanoma. In particular, CD68+ TAMs and their abundance in tumor nests were associated with poor prognostic factors. However, the correlation of low stromal CD163+ TAM proportion with a poor prognosis indicates that the role of TAMs depends on their subtype and microanatomical localization.

Estrogen receptor α in T cells suppresses follicular helper T cell responses and prevents autoimmunity

Estrogen receptor alpha (ERα) is a sex hormone nuclear receptor that regulates various physiological events, including the immune response. Although there have been some recent studies on ERα regarding subsets of T cells, such as Th1, Th2, Th17, and Treg cells, its role in follicular helper T (TFH) cells has not yet been elucidated. To determine whether ERα controls TFH response and antibody production, we generated T cell-specific ERα knockout (KO) mice by utilizing the CD4-Cre/ERα flox system (CD4-ERα KO) and then analyzed their phenotype. At approximately 1 year of age, CD4-ERα KO mice spontaneously showed mild autoimmunity with increased autoantibody production and CD4⁺CD44⁺CXCR5⁺Bcl-6⁺ TFH cells in the mesenteric lymph nodes and spleen. We next immunized 6-8-week-old CD4-ERα KO mice with sheep red blood cells (SRBCs), which resulted in an increased proportion of TFH cells and germinal center (GC) responses. In addition, 17β-estradiol (E2) treatment decreased TFH responses in wild-type mice and suppressed the mRNA expression of Bcl-6 and IL-21. Finally, we confirmed that the production of high-affinity antigen-specific antibodies and isotype class switching induced by NP-conjugated ovalbumin immunization were elevated in CD4-ERα KO mice under sufficient estrogen conditions. These results collectively demonstrate that the female sex hormone receptor ERα inhibits the TFH cell response and GC reaction to control autoantibody production, which was related to estrogen signaling and autoimmunity.

A review on the interactions between the tumor microenvironment and androgen receptor signaling in prostate cancer

Prostate cancer growth is controlled by androgen receptor signaling via both androgen-dependent and androgen-independent pathways. Furthermore, the prostate is an immune competent organ with inflammatory changes both within the systemic and local environment contributing to the reprogramming of the prostatic epithelium with consistently elevated lymphocyte infiltration and proinflammatory cytokines being found in prostate cancer. The crosstalk between the tumor microenvironment and androgen receptor signaling is complex with both protumorigenic and antitumorigenic roles observed. However, despite an increase in immune checkpoint inhibitors and inflammatory signaling blockades available for a range of cancer types, we are yet to see substantial progress in the treatment of prostate cancer. Therefore, this review aims to summarize the tumor microenvironment and its impact on androgen receptor signaling in prostate cancer.

Suppressed androgen receptor expression promotes M2 macrophage reprogramming through the STAT3/SOCS3 pathway

Macrophages are important mediators of inflammatory cardiovascular diseases, and various macrophage phenotypes exert opposite effects during inflammation. In our previous study, we proved that suppressed androgen receptor (AR) alleviated inflammation during experimental autoimmune myocarditis (EAM). As anti-inflammatory cells, whether M2 macrophages are involved in this process remains unclear. Here, we showed that anti-inflammatory cytokines and M2 macrophages were elevated when AR was suppressed during EAM. In IL-4 stimulation-induced M2 macrophages, impaired AR with ASC-J9 increased the expression of M2 macrophage-related factors. Moreover, suppressed AR expression resulted in macrophage M2 polarization by reducing SOCS3 production and enhancing STAT3 activation. Taken together, our data suggest that AR plays a critical role in macrophage polarization and suppressed redundant AR expression promotes anti-inflammatory M2 macrophages reprogramming. This study suggests a potential therapeutic agent for inflammatory cardiomyopathy through the use of ASC-J9.

Invalid freeze-dried platelet gel promotes wound healing

Wound healing is the curative process of tissue injury, composed of three phases: the inflammatory phase, proliferative phase, followed by the maturation cum remodeling phase. Various treatment options were previously depicted for wound healing, however a treatment that accelerates these phases would be highly valuable. Platelet aggregation at the bleeding vessels and release of various growth factors are the most promising factors that stimulates the wound healing progress. In the present study, we hypothesized that the freeze-dried platelet which were normally discarded from the blood banks due to invalidity, might be promising to accelerate the phases of wound healing. The invalid freeze-dried platelets were prepared to a gel form called invalid freeze-dried platelet gel (IF-PG), which was tested for its efficacy in a cutaneous punch wound model in rats. Mupirocin antibiotic gel was used as a bio-equivalent formulation. The wound healing phases and changes in the wound sites were determined by assessing the wound sizes, histopathological analysis, immunohistochemical staining. The re-epithelialization at the wound sites at different time intervals till the wound closure was also determined. Our results suggest the beneficial effects of IF-PG; in reducing the wound area and accelerating wound closure in the cutaneous punch wound in rats. Histopathology and immunostaining results support the improvements in the wound when treated with IF-PG, which were similar to that of mupirocin antibiotic gel. Our preliminary findings also warrant the competency of IF-PG in modulating the different phases of wound healing process. In conclusion, IF-PG might be a resourceful alternative for the wound care management, however further studies are required to validate its impact on various growth factors before proceeding to clinical studies.

Chitosan Membrane Modified With a New Zinc(II)-Vanillin Complex Improves Skin Wound Healing in Diabetic Rats

The treatment of chronic wounds is considered a public health problem. When the condition affects at-risk groups such as those with diabetics, it becomes a great clinical challenge. In this work, we evaluated the healing effects of a new zinc complex, [Zn(phen)(van)2], identified as ZPV, which was synthesized, characterized and associated with chitosan (CS) membranes and tested on cutaneous wounds of diabetic rats. Chitosan membranes were modified by Schiff base reaction with the complex under two experimental conditions (14 and 21 days), resulting in membranes with concentrations of complex equal to 0.736 μmol cm-2 (CS-ZPV1) and 1.22 μmol cm-2 (CS-ZPV2). Release assays in aqueous medium indicated that the membranes release the complex gradually when exposed to an aqueous medium. Diabetes was inducted in Wistar rats using 40 mg/kg (i.v.) streptozotocin. On the 7th day after diabetic induction, a circular excision on the skin (1.0 cm) was performed with a punch. The lesions were treated with the pure chitosan membrane and the membrane associated with the zinc-vanillin complex in two different doses. Skin samples were subjected to macroscopic and histopathological analyses, cytokine (TNF-α, IL-1β, and IL-10) quantification and reverse transcriptase polymerase chain reaction (TGF-β and VEGF) assays. The analyses showed a decrease in wound size, reepithelialization, angiogenic stimulus, collagen deposition, and reduced levels of TNF-α and IL-1β as well as increased IL-10 and gene expression of TGF-β and VEGF. The evaluated parameters suggest that CS-ZPV in the two concentrations tested may be effective in the treatment of chronic wounds.

Androgen receptor functions as transcriptional repressor of cancer-associated fibroblast activation

The aging-associated increase of cancer risk is linked with stromal fibroblast senescence and concomitant cancer-associated fibroblast (CAF) activation. Surprisingly little is known about the role of androgen receptor (AR) signaling in this context. We have found downmodulated AR expression in dermal fibroblasts underlying premalignant skin cancer lesions (actinic keratoses and dysplastic nevi) as well as in CAFs from the 3 major skin cancer types, squamous cell carcinomas (SCCs), basal cell carcinomas, and melanomas. Functionally, decreased AR expression in primary human dermal fibroblasts (HDFs) from multiple individuals induced early steps of CAF activation, and in an orthotopic skin cancer model, AR loss in HDFs enhanced tumorigenicity of SCC and melanoma cells. Forming a complex, AR converged with CSL/RBP-Jκ in transcriptional repression of key CAF effector genes. AR and CSL were positive determinants of each other's expression, with BET inhibitors, which counteract the effects of decreased CSL, restoring AR expression and activity in CAFs. Increased AR expression in these cells overcame the consequences of CSL loss and was by itself sufficient to block the growth and tumor-enhancing effects of CAFs on neighboring cancer cells. As such, the findings establish AR as a target for stroma-focused cancer chemoprevention and treatment.

Effects of Carbon Arc Lamp Irradiation on Wound Healing in a Rat Cutaneous Full-Thickness Wound Model

OBJECTIVE

The objective of the present study was to investigate the application of a carbon arc lamp on wound healing in a rat cutaneous full-thickness wound model.

BACKGROUND DATA

In clinical practice, wound healing has been promoted by irradiation with a carbon arc lamp. However, the corresponding mechanism has not been clearly defined.

METHODS

A cutaneous full-thickness wound on the back of rats was irradiated using a carbon arc lamp at a wavelength peak range of 620-740 nm with 54 J/cm2. Injured sham-irradiated control rats were used as the control. The rats were euthanized after 7, 14, and 21 days, while wound reepithelialization and healing quality were examined by histological analyses with comparison between groups. Cell proliferation was observed by 5-bromo-2'-deoxyuridine (BrdU) immunohistochemical staining.

RESULTS

Irradiation by the carbon arc lamp significantly accelerated wound healing. The wound-healing rate in the treated group at day 21 was 98.42% ± 0.56%, compared with 93.58% ± 1.26% in the control group (p < 0.05). Significant increases in the length of epithelial edges, collagen content, and microvessel density were observed in the wound sites in the treated group at days 7, 14, and 21 (p < 0.05). Moreover, the number of BrdU-labeled cells increased in the wound edge at days 7 and 14 due to irradiation (p < 0.05).

CONCLUSIONS

The results demonstrated that the carbon arc lamp can promote wound healing together with improvement in its quality by stimulating cell proliferation.

Sex Hormones Regulate Innate Immune Cells and Promote Sex Differences in Respiratory Virus Infection

Sex differences in the incidence and severity of respiratory virus infection are widely documented in humans and murine models and correlate with sex biases in numbers and/or functional responses of innate immune cells in homeostasis and lung infection. Similarly, changes in sex hormone levels upon puberty, pregnancy, and menopause/aging are associated with qualitative and quantitative differences in innate immunity. Immune cells express receptors for estrogens (ERα and ERβ), androgens (AR), and progesterone (PR), and experimental manipulation of sex hormone levels or receptors has revealed that sex hormone receptor activity often underlies sex differences in immune cell numbers and/or functional responses in the respiratory tract. While elegant studies have defined mechanistic roles for sex hormones and receptors in innate immune cells, much remains to be learned about the cellular and molecular mechanisms of action of ER, PR, and AR in myeloid cells and innate lymphocytes to promote the initiation and resolution of antiviral immunity in the lung. Here, we review the literature on sex differences and sex hormone regulation in innate immune cells in the lung in homeostasis and upon respiratory virus infection.

Androgen exposure potentiates formation of intratubular communities and renal abscesses by Escherichia coli

Females across their lifespan and certain male populations are susceptible to urinary tract infections (UTI). The influence of female vs. male sex on UTI is incompletely understood, in part because preclinical modeling has been performed almost exclusively in female mice. Here, we employed established and new mouse models of UTI with uropathogenic Escherichia coli (UPEC) to investigate androgen influence on UTI pathogenesis. Susceptibility to UPEC UTI in both male and female hosts was potentiated with 5α-dihydrotestosterone, while males with androgen receptor deficiency and androgenized females treated with the androgen receptor antagonist enzalutamide were protected from severe pyelonephritis. In androgenized females and in males, UPEC formed dense intratubular, biofilm-like communities, some of which were sheltered from infiltrating leukocytes by the tubular epithelium and by peritubular fibrosis. Abscesses were nucleated by small intratubular collections of UPEC first visualized at five days postinfection and briskly expanded over the subsequent 24 hours. Male mice deficient in Toll-like receptor 4, which fail to contain UPEC within abscesses, were susceptible to lethal dissemination. Thus, androgen receptor activation imparts susceptibility to severe upper-tract UTI in both female and male murine hosts. Visualization of intratubular UPEC communities illuminates early renal abscess pathogenesis and the role of abscess formation in preventing dissemination of infection. Additionally, our study suggests that androgen modulation may represent a novel therapeutic route to combat recalcitrant or recurrent UTI in a range of patient populations.

Liver inflammation and regeneration in drug-induced liver injury: sex matters!

Drug-induced liver injury (DILI) remains a clinical challenge due to the poorly predictable outcomes. Accordingly, considerable efforts have been devoted to unravel the risk factors responsible for DILI worsening toward acute liver failure (ALF), liver transplantation (LT), and/or death. From a pathogenic point of view, exhaustion of drug metabolizing pathways, cell death mechanisms, activation of local immune cells, such as Kupffer cells, and recruitment of inflammatory leukocytes including monocytes and lymphocytes are key drivers of DILI progression. Taking into account that the liver is a sexually dimorphic organ, in the recent past several studies aimed to investigate the implications of gender differences in promoting DILI. While sex discrepancies in DILI include the hepatic drug metabolism or direct effects of steroid hormones (e.g. androgens and estrogens) on signaling pathways in the liver, relatively little is known on gender differences in modulating liver innate immune responses. In a previous issue of Clinical Science, Bizzaro and co-workers, analyzed sex-dependent differences in experimental acute liver injury and regeneration in mice. The authors observed a time-delay in the recovery process in male animals associated with a higher recruitment of monocytes expressing the androgen receptor (AR) as compared with females. Treatment of male mice with the pharmacological AR antagonist flutamide reduced monocyte recruitment in mice. Likewise, human male patients suffering from DILI displayed higher circulating immature and potentially more inflammatory monocytes. Altogether, these observations provide new insights into sex-dependent immune mechanisms in the context of acute liver injury, suggesting gender disparate inflammatory and regenerative responses following DILI.

Immunomodulatory activity of curcumin-entrapped poly d,l-lactic-co-glycolic acid nanoparticles in mice

Background

Studies have shown that curcumin from Curcuma longa has a wide range of medicinal and immunomodulatory properties. These activities have, however, been hindered by its low bioavailability. Meanwhile, incorporation of nanoparticles has been shown to increase bioavailability of certain drugs. This study was, therefore, conducted to comparatively evaluate the immunomodulatory activity of free and nanoparticulate curcumin in mice.

Methods

Healthy albino mice were sensitized with sheep red blood cells (SRBCs) and thereafter free and nanoparticulate curcumin were administered orally at doses of 5 mg/kg/day and 10 mg/kg/day for 10 days to the mice. The assessment of the immunomodulatory activity was carried out by determining the humoral and cell-mediated immune responses using hemagglutination and delayed-type hypersensitivity assays, respectively. Hematological components and some lymphoid organs of treated mice were further evaluated.

Results

The study showed that nanoparticulate curcumin stimulated higher early cell-mediated immune response at 5 mg/kg and 10 mg/kg when compared to control. While nanoparticulate curcumin significantly stimulated primary humoral immune response with 9.00 ± 1.00 antibody titre (p < 0.05), the free curcumin suppressed the immunity with 3.33 ± 0.67 antibody titre when compared to control. Similar result was observed with secondary humoral antibody titres. Production of white blood cells and weight of the lymphoid organs were also enhanced in the groups that received 10 mg/kg nanocurcumin.

Conclusion

This work showed that poly d,l-lactic-co-glycolic acid entrapped curcumin nanoparticle could increase bioavailability of curcumin for improved immunity.

New therapy with ASC-J9® to suppress the prostatitis via altering the cytokine CCL2 signals

Prostatitis is a common disease contributing to 8% of all urologist visits. Yet the etiology and effective treatment remain to be further elucidated. Using a non-obese diabetes mouse model that can be induced by autoimmune response for the spontaneous development of prostatitis, we found that injection of the ASC-J9^® at 75 mg/Kg body weight/48 hours led to significantly suppressed prostatitis that was accompanied with reduction of lymphocyte infiltration with reduced CD4⁺ T cells in prostate. In vitro studies with a co-culture system also confirmed that ASC-J9^® treatment could suppress the CD4⁺ T cell migration to prostate stromal cells. Mechanisms dissection indicated that ASC-J9^® can suppress CD4⁺ T cell migration via decreasing the cytokine CCL2 in vitro and in vivo, and restoring CCL2 could interrupt the ASC-J9^® suppressed CD4⁺ T cell migration. Together, results from in vivo and in vitro studies suggest that ASC-J9^® can suppress prostatitis by altering the autoimmune response induced by CD4⁺ T cell recruitment, and using ASC-J9^® may help us to develop a potential new therapy to battle the prostatitis with little side effects.

ASC-J9® suppresses prostate cancer cell invasion via altering the sumoylation-phosphorylation of STAT3

The androgen-deprivation therapy (ADT) to either reduce the androgen biosynthesis (for example, Abiraterone) or to prevent binding of androgen to the androgen receptor (AR), for example using Casodex or Enzalutamide, which may result in .decrease of the prostate cancer (PCa) cell growth, yet may also increase the PCa cell invasion. In contrast, the recently identified AR degradation enhancer ASC-J9^® may function via degrading the AR protein to simultaneously suppress the PCa cell proliferation and invasion. The details of this unique mechanism, however, remain unclear. Here we found that ASC-J9^® could suppress PCa cell invasion via inducing the sumoylation of STAT3, thereby inhibiting the STAT3 phosphorylation that led to suppress the EMT-SNAIL2 signals in both PCa DU145 and PC3 AR-negative cells. Mutation of lysine-679 on the sumoylation site of the STAT3 effectively blocked the ASC-J9^®-suppressed PCa cell invasion in both in vitro cell lines and in vivo mouse models. These results suggest that in addition to degrading AR to suppress PCa cell proliferation, ASC-J9^® can also function through an AR-independent mechanism via modulating the STAT3 sumoylation to alter the phospho-STAT3 status to suppress the PCa cell invasion. These dual functions of ASC-J9^® to suppress PCa proliferation and invasion (via altering STAT3 sumoylation) may help us to develop a better anti-AR compound that may overcome the current antiandrogens' unwanted side-effect of increasing the metastasis to better suppress the castration-resistant PCa progression.

Zebrafish androgen receptor is required for spermatogenesis and maintenance of ovarian function

The androgen receptor (AR) is a nuclear receptor protein family member and inducible transcription factor that modulates androgen target gene expression. Studies using a mouse model confirmed the need for ar in reproductive development, particularly spermatogenesis. Here, we investigated the role of ar in zebrafish using CRISPR/Cas9 gene targeting technology. Targeted disruption of ar in zebrafish increases the number of female offspring and increases offspring weight. In addition, ar-null male zebrafish have female secondary sex characteristics. More importantly, targeted disruption of ar in zebrafish causes male infertility via defective spermatogenesis and female premature ovarian failure during growth. Mechanistic assays suggest that these effects are caused by fewer proliferated cells and more apoptotic cells in ar-null testes. Moreover, genes involved in reproductive development, estradiol induction and hormone synthesis were dys-regulated in testes and ovaries and the reproductive-endocrine axis was disordered. Our data thus suggest that the zebrafish ar is required for spermatogenesis and maintenance of ovarian function, which confirms evolutionarily conserved functions of ar in vertebrates, as well as indicates that ar-null zebrafish are a suitable model for studying pathologic mechanisms related to androgen disorders.

Sex-dependent differences in inflammatory responses during liver regeneration in a murine model of acute liver injury

A sexual dimorphism in liver inflammation and repair was previously demonstrated. Its cellular dissection in the course of acute liver injury (ALI) was explored. BALB/c mice were treated with carbon tetrachloride (CCl₄) by intraperitoneal injection and killed after 3, 5, and 8 days. Histological and hepatic cell population analyses were performed. The correlation between androgen receptor (AR) expression and liver recruited inflammatory cells was investigated by treatment with the AR antagonist flutamide. Additionally, patients with a diagnosis of drug induced liver injury (DILI) were included in the study, with a particular focus on gender dimorphism in circulating monocytes. A delayed resolution of necrotic damage and a higher expression of proinflammatory cytokines were apparent in male mice along with a slower recruitment of inflammatory monocytes. F4/80⁺CD11b⁺ macrophages and CD11b^highGr-1^high monocytes expressed AR and were recruited later in male compared with female livers after CCl₄ treatment. Moreover, CD11b^highAR⁺Gr-1^high recruitment was negatively modulated by flutamide in males. Analysis of DILI patients showed overall a significant reduction in circulating mature monocytes compared with healthy subjects. More interestingly, male patients had higher numbers of immature monocytes compared with female patients.A stronger cytotoxic tissue response was correlated with an impaired recruitment of CD11b^highAR⁺Gr-1^high cells and F4/80⁺CD11b⁺ macrophages in the early inflammatory phase under AR signaling. During DILI, a dimorphic immune response was apparent, characterized by a massive recruitment of monocytes to the liver both in males and females, but only in males was this recruitment sustained by a turnover of immature monocytes.

Sex differences in abdominal aortic aneurysms

Abdominal aortic aneurysm (AAA) is a vascular disorder with a high case fatality rate in the instance of rupture. AAA is a multifactorial disease, and the etiology is still not fully understood. AAA is more likely to occur in men, but women have a greater risk of rupture and worse prognosis. Women are reportedly protected against AAA possibly by premenopausal levels of estrogen and are, on average, diagnosed at older ages than men. Here, we review the present body of research on AAA pathophysiology in humans, animal models, and cultured cells, with an emphasis on sex differences and sex steroid hormone signaling.

Finasteride accelerates prostate wound healing after thulium laser resection through DHT and AR signalling

OBJECTIVES

Urinary tract infection, urinary frequency, urgency, urodynia and haemorrhage are common post-operative complications of thulium laser resection of the prostate (TmLRP). Our study mainly focuses on the role of finasteride in prostate wound healing through AR signalling.

MATERIALS AND METHODS

TmLRP beagles were randomly distributed into different treatment groups. Serum and intra-prostatic testosterone and DHT level were determined. Histological analysis was conducted to study the re-epithelialization and inflammatory response of the prostatic urethra in each group. We investigated the role of androgen in proliferation and inflammatory response in prostate. In addition, the effects of TNF-α on prostate epithelium and stromal cells were also investigated.

RESULTS

Testosterone and DHT level increased in testosterone group and DHT decreased in finasteride group. Accelerated wound healing of prostatic urethra was observed in the finasteride group. DHT suppressed proliferation of prostate epithelium and enhanced inflammatory response in prostate. We confirmed that DHT enhanced macrophages TNF-α secretion through AR signalling. TNF-α suppressed proliferation of prostate epithelial cells and retarded cell migration. TNF-α also played a pivotal role in suppressing fibroblasts activation and contraction.

CONCLUSION

Testosterone treatment repressed re-epithelialization and wound healing of prostatic urethra. Finasteride treatment may be an effective way to promote prostate re-epithelialization.

Genetic architecture of acne vulgaris

Acne vulgaris is a ubiquitary skin disease characterized by chronic inflammation of the pilosebaceous unit resulting from bacterial colonization of hair follicles by Propionibacterium acnes, androgen-induced increased sebum production, altered keratinization and inflammation. Here, we review our current understanding of the genetic architecture of this intriguing disease. We analysed genomewide association studies (GWAS) and candidate genes studies for acne vulgaris. Moreover, we included GWAS studies for the associated disease polycystic ovary syndrome (PCOS). Overall, the available data revealed sixteen genetic loci flagged by single nucleotide polymorphisms (SNPs), none of which has been confirmed yet by independent studies. Moreover, a GWAS for PCOS identified 21 susceptible loci. The genetic architecture is complex which has been revealed by GWAS. Further and larger studies in different populations are required to confirm or disprove results from candidate gene studies as well to identify signals that may overlap between different populations. Finally, studies on rare genetic variants in acne and associated diseases like PCOS may deepen our understanding of its pathogenesis.

Seasonal Patterns of Variation in Steroid Plasma Levels and Immune Parameters in Anurans from Brazilian Semiarid Area

Elevated androgens and glucocorticoids displayed by males during the reproductive season have been proposed to mediate a possible trade-off between reproduction and immunocompetence. Anurans living in arid and semiarid environments display a strong seasonal reproduction, which could accentuate the variation in physiological, immunological, and behavioral parameters. We studied covariation between steroid plasma levels, morphometric variables associated with body condition and immunity, leukocyte profile, parasite load, and response to an immunological challenge across different phases of the annual life-history cycle of three anuran species from a Brazilian semiarid area. Our results showed a seasonal pattern of covariation among leukocyte parameters, kidney mass, and steroid plasma levels, with higher values measured during the reproductive season, particularly when males were sampled during calling activity. Moreover, these anurans showed a stronger response to an immunological challenge during the reproductive period. The immunosuppression during the dry period was particularly evident for the species that aestivate, indicating that the availability of energetic resources might be an important factor determining seasonal variation in inflammatory response. Intensity of the helminth infection was associated with eosinophil count but showed a more complex pattern with regard to androgens levels. These data emphasize that variations in the intensity of helminth infection might be more closely related to specific aspects of the immune response than to the general seasonal patterns of variation in steroid plasma levels, total circulating leukocytes, and inflammatory response.

Sex Drives Dimorphic Immune Responses to Viral Infections

New attention to sexual dimorphism in normal mammalian physiology and disease has uncovered a previously unappreciated breadth of mechanisms by which females and males differentially exhibit quantitative phenotypes. Thus, in addition to the established modifying effects of hormones, which prenatally and postpubertally pattern cells and tissues in a sexually dimorphic fashion, sex differences are caused by extragonadal and dosage effects of genes encoded on sex chromosomes. Sex differences in immune responses, especially during autoimmunity, have been studied predominantly within the context of sex hormone effects. More recently, immune response genes have been localized to sex chromosomes themselves or found to be regulated by sex chromosome genes. Thus, understanding how sex impacts immunity requires the elucidation of complex interactions among sex hormones, sex chromosomes, and immune response genes. In this Brief Review, we discuss current knowledge and new insights into these intricate relationships in the context of viral infections.

Genomic and non-genomic effects of androgens in the cardiovascular system: clinical implications

The principle steroidal androgens are testosterone and its metabolite 5α-dihydrotestosterone (DHT), which is converted from testosterone by the enzyme 5α-reductase. Through the classic pathway with androgens crossing the plasma membrane and binding to the androgen receptor (AR) or via mechanisms independent of the ligand-dependent transactivation function of nuclear receptors, testosterone induces genomic and non-genomic effects respectively. AR is widely distributed in several tissues, including vascular endothelial and smooth muscle cells. Androgens are essential for many developmental and physiological processes, especially in male reproductive tissues. It is now clear that androgens have multiple actions besides sex differentiation and sexual maturation and that many physiological systems are influenced by androgens, including regulation of cardiovascular function [nitric oxide (NO) release, Ca²⁺ mobilization, vascular apoptosis, hypertrophy, calcification, senescence and reactive oxygen species (ROS) generation]. This review focuses on evidence indicating that interplay between genomic and non-genomic actions of testosterone may influence cardiovascular function.

Pharmacological activation of AMPK inhibits incision-evoked mechanical hypersensitivity and the development of hyperalgesic priming in mice

New therapeutics to manage post-surgical pain are needed to mitigate the liabilities of opioid and other analgesics. Our previous work shows that key modulators of excitability in peripheral nociceptors, such as extracellular signal-regulated kinases (ERK) are inhibited by activation of adenosine monophosphate activated protein kinase (AMPK). We hypothesized that AMPK activation would attenuate acute incision-evoked mechanical hypersensitivity and the development of hyperalgesic priming caused by surgery in mice. Here we have used a variety of administration routes and combinations of AMPK activators to test this hypothesis. Topical administration of a resveratrol-based cream inhibited acute mechanical hypersensitivity evoked by incision and blocked the development of hyperalgesic priming. We also observed that systemic administration of metformin dose-dependently inhibited incision-evoked mechanical hypersensitivity and hyperalgesic priming. Interestingly, low doses of systemic metformin and local resveratrol that had no acute effect were able to mitigate development of hyperalgesic priming. Combined treatment with doses of systemic metformin and local resveratrol that were not effective on their own enhanced the acute efficacy of the individual AMPK activators for post-surgical mechanical pain alleviation and blocked the development of hyperalgesic priming. Finally, we used dorsal root ganglion (DRG) neurons in culture to show that resveratrol and metformin given in combination shift the concentration-response curve for AMPK activation to the left and increase the magnitude of AMPK activation. Therefore, we find that topical administration is an effective treatment route of administration and combining systemic and local treatments led to anti-nociceptive efficacy in acute mechanical hypersensitivity at doses that were not effective alone. Collectively our work demonstrates a specific effect of AMPK activators on post-surgical pain and points to novel therapeutic opportunities with potential immediate impact in the clinical setting.

FOXO3, estrogen receptor alpha, and androgen receptor impact tumor growth rate and infiltration of dendritic cell subsets differentially between male and female mice

Tumors evade immune recognition and destruction in many ways including the creation of an immune-suppressive tumor microenvironment (TME). Dendritic cells (DC) that infiltrate the TME are tolerogenic, and suppress effector T cells and anti-tumor activity. Previous reports demonstrated that a key regulator of tolerance in DC is the transcription factor FOXO3. Gender disparity has been studied in cancer in relation to incidence, aggressiveness, and prognosis. Few studies have touched on the importance in relation to impact on the immune system. In the current study, we show that there are significant differences in tumor growth between males and females. Additionally, frequencies and the function of FOXO3 expressed by DC subsets that infiltrate tumors vary between genders. Our results show for the first time that DC FOXO3 expression and function is altered in females. In vitro results indicate that these differences may be the result of exposure to estrogen. These differences may be critical considerations for the enhancement of immunotherapy for cancer.

Androgen Deprivation Accelerates the Prostatic Urethra Wound Healing After Thulium Laser Resection of the Prostate by Promoting Re-Epithelialization and Regulating the Macrophage Polarization

BACKGROUND

Complications after a thulium laser resection of the prostate (TmLRP) are related to re-epithelialization of the prostatic urethra. Since prostate growth and development are induced by androgen, the aim of this study was to determine the role and explore the mechanism of androgen in wound healing of the prostatic urethra.

METHODS

Beagles that received TmLRPs were randomly distributed into a castration group, a testosterone undecanoate (TU) group, and a control group. The prostate wound was assessed once a week using a cystoscope. Histological analysis was then carried out to study the re-epithelialization of the prostatic urethra in each group. The inflammatory response in the wound tissue and urine was also investigated.

RESULTS

The healing of the prostatic urethra after a TmLRP was more rapid in the castration group and slower in the TU group than that in the control group. Castration accelerated re-epithelialization by promoting basal cell proliferation in the wound surface and beneath the wound and by accelerating the differentiation of basal cells into urothelial cells. Castration reduced the duration of the inflammatory phase and induced the conversion of M1 macrophages to M2 macrophages, thus accelerating the maturation of the wound. By contrast, androgen supplementation enhanced the inflammatory response and prolonged the inflammatory phase. Moreover, the anti-inflammatory phase was delayed and weakened.

CONCLUSION

Androgen deprivation promotes re-epithelialization of the wound, regulates the inflammatory response, and accelerates wound healing of the prostatic urethra after a TmLRP. Prostate 77:708-717, 2017. © 2017 Wiley Periodicals, Inc.

Immunosuppressive Effects of Natural α,β-Unsaturated Carbonyl-Based Compounds, and Their Analogs and Derivatives, on Immune Cells: A Review

The immune system is complex and pervasive as it functions to prevent or limit infections in the human body. In a healthy organism, the immune system and the redox balance of immune cells maintain homeostasis within the body. The failure to maintain the balance may lead to impaired immune response and either over activity or abnormally low activity of the immune cells resulting in autoimmune or immune deficiency diseases. Compounds containing α,β-unsaturated carbonyl-based moieties are often reactive. The reactivity of these groups is responsible for their diverse pharmacological activities, and the most important and widely studied include the natural compounds curcumin, chalcone, and zerumbone. Numerous studies have revealed the mainly immunosuppressive and anti-inflammatory activities of the aforesaid compounds. This review highlights the specific immunosuppressive effects of these natural α,β-unsaturated carbonyl-based compounds, and their analogs and derivatives on different types of immune cells of the innate (granulocytes, monocytes, macrophages, and dendritic cells) and adaptive (T cells, B cells, and natural killer cells) immune systems. The inhibitory effects of these compounds have been comprehensively studied on neutrophils, monocytes and macrophages but their effects on T cells, B cells, natural killer cells, and dendritic cells have not been well investigated. It is of paramount importance to continue generating experimental data on the mechanisms of action of α,β-unsaturated carbonyl-based compounds on immune cells to provide useful information for ensuing research to discover new immunomodulating agents.

Effects of Fibroin Microcarriers on Inflammation and Regeneration of Deep Skin Wounds in Mice

The process of tissue regeneration following damage takes place with direct participation of the immune system. The use of biomaterials as scaffolds to facilitate healing of skin wounds is a new and interesting area of regenerative medicine and biomedical research. In many ways, the regenerative potential of biological material is related to its ability to modulate the inflammatory response. At the same time, all foreign materials, once implanted into a living tissue, to varying degree cause an immune reaction. The modern approach to the development of bioengineered structures for applications in regenerative medicine should be directed toward using the properties of the inflammatory response that improve healing, but do not lead to negative chronic manifestations. In this work, we studied the effect of microcarriers comprised of either fibroin or fibroin supplemented with gelatin on the dynamics of the healing, as well as inflammation, during regeneration of deep skin wounds in mice. We found that subcutaneous administration of microcarriers to the wound area resulted in uniform contraction of the wounds in mice in our experimental model, and microcarrier particles induced the infiltration of immune cells. This was associated with increased expression of proinflammatory cytokines TNF, IL-6, IL-1β, and chemokines CXCL1 and CXCL2, which contributed to full functional recovery of the injured area and the absence of fibrosis as compared to the control group.

Skin steroidogenesis in health and disease

The skin is an important extra-gonadal steroidogenic organ, capable of metabolizing various hormones from their precursors, as well as of synthesizing de novo a broad palette of sex steroids and glucocorticoids from cholesterol. In this manuscript, we review the major steroidogenic properties of human skin and we suggest steroidogenesis' impairment as a cardinal factor for various pathological conditions such as acne, rosacea, atopic dermatitis, and androgenic alopecia.

Role of androgens in dhea-induced rack1 expression and cytokine modulation in monocytes

Background

Over the past fifteen years, we have demonstrated that cortisol and dehydroepiandrosterone (DHEA) have opposite effects on the regulation of protein kinase C (PKC) activity in the context of the immune system. The anti-glucocorticoid effect of DHEA is also related to the regulation of splicing of the glucocorticoid receptor (GR), promoting the expression of GRβ isoform, which acts as a negative dominant form on GRα activity. Moreover, it is very well known that DHEA can be metabolized to androgens like testosterone, dihydrotestosterone (DHT), and its metabolites 3α-diol and 3β-diol, which exert their function through the binding of the androgen receptor (AR). Based on this knowledge, and on early observation that castrated animals show results similar to those observed in old animals, the purpose of this study is to investigate the role of androgens and the androgen receptor (AR) in DHEA-induced expression of the PKC signaling molecule RACK1 (Receptor for Activated C Kinase 1) and cytokine production in monocytes.

Results

Here we demonstrated the ability of the anti-androgen molecule, flutamide, to counteract the stimulatory effects of DHEA on RACK1 and GRβ expression, and cytokine production. In both THP-1 cells and human peripheral blood mononuclear cells (PBMC), flutamide blocked the effects of DHEA, suggesting a role of the AR in these effects. As DHEA is not considered a direct AR agonist, we investigated the metabolism of DHEA in THP-1 cells. We evaluated the ability of testosterone, DHT, and androstenedione to induce RACK1 expression and cytokine production. In analogy to DHEA, an increase in RACK1 expression and in LPS-induced IL–8 and TNF–α production was observed after treatment with these selected androgens. Finally, the silencing of AR with siRNA completely prevented DHEA-induced RACK1 mRNA expression, supporting the idea that AR is involved in DHEA effects.

Conclusions

We demonstrated that the conversion of DHEA to active androgens, which act via AR, is a key mechanism in the effect of DHEA on RACK1 expression and monocyte activation. This data supports the existence of a complex hormonal balance in the control of immune modulation, which can be further studied in the context of immunosenescence and endocrinosenescence.

Androgen actions in mouse wound healing: Minimal in vivo effects of local antiandrogen delivery

The aims of this work were to define the role of androgens in female wound healing and to develop and characterize a novel wound dressing with antiandrogens. Androgens retard wound healing in males, but their role in female wound healing has not been established. To understand androgen receptor (AR)-mediated androgen actions in male and female wound healing, we utilized the global AR knockout (ARKO) mouse model, with a mutated AR deleting the second zinc finger to disrupt DNA binding and transcriptional activation. AR inactivation enhanced wound healing rate in males by increasing re-epithelialization and collagen deposition even when wound contraction was eliminated. Cell proliferation and migration in ARKO male fibroblasts was significantly increased compared with wild-type (WT) fibroblasts. However, ARKO females showed a similar healing rate compared to WT females. To exploit local antiandrogen effects in wound healing, while minimizing off-target systemic effects, we developed a novel electrospun polycaprolactone (PCL) scaffold wound dressing material for sustained local antiandrogen delivery. Using the antiandrogen hydroxyl flutamide (HF) at 1, 5, and 10 mg/mL in PCL scaffolds, controlled HF delivery over 21 days significantly enhanced in vitro cell proliferation of human dermal fibroblasts and human keratinocytes. HF-PCL scaffolds also promoted in vivo wound healing in mice compared with open wounds but not to PCL scaffolds.

Sexual dimorphism in cancer

The incidence of many types of cancer arising in organs with non-reproductive functions is significantly higher in male populations than in female populations, with associated differences in survival. Occupational and/or behavioural factors are well-known underlying determinants. However, cellular and molecular differences between the two sexes are also likely to be important. In this Opinion article, we focus on the complex interplay that sex hormones and sex chromosomes can have in intrinsic control of cancer-initiating cell populations, the tumour microenvironment and systemic determinants of cancer development, such as the immune system and metabolism. A better appreciation of these differences between the two sexes could be of substantial value for cancer prevention as well as treatment.

Androgen receptor (AR) in cardiovascular diseases

Cardiovascular diseases (CVDs) are still the highest leading cause of death worldwide. Several risk factors have been linked to CVDs, including smoking, diabetes, hyperlipidemia, and gender among others. Sex hormones, especially the androgen and its receptor, androgen receptor (AR), have been linked to many diseases with a clear gender difference. Here, we summarize the effects of androgen/AR on CVDs, including hypertension, stroke, atherosclerosis, abdominal aortic aneurysm (AAA), myocardial hypertrophy, and heart failure, as well as the metabolic syndrome/diabetes and their impacts on CVDs. Androgen/AR signaling exacerbates hypertension, and anti-androgens may suppress hypertension. Androgen/AR signaling plays dual roles in strokes, depending on different kinds of factors; however, generally males have a higher incidence of strokes than females. Androgen and AR differentially modulate atherosclerosis. Androgen deficiency causes elevated lipid accumulation to enhance atherosclerosis; however, targeting AR in selective cells without altering serum androgen levels would suppress atherosclerosis progression. Androgen/AR signaling is crucial in AAA development and progression, and targeting androgen/AR profoundly restricts AAA progression. Men have increased cardiac hypertrophy compared with age-matched women that may be due to androgens. Finally, androgen/AR plays important roles in contributing to obesity and insulin/leptin resistance to increase the metabolic syndrome.

The tumor suppressor ING1b is a novel corepressor for the androgen receptor and induces cellular senescence in prostate cancer cells

The androgen receptor (AR) signaling is critical for prostate cancer (PCa) progression to the castration-resistant stage with poor clinical outcome. Altered function of AR-interacting factors may contribute to castration-resistant PCa (CRPCa). Inhibitor of growth 1 (ING1) is a tumor suppressor that regulates various cellular processes including cell proliferation. Interestingly, ING1 expression is upregulated in senescent primary human prostate cells; however, its role in AR signaling in PCa was unknown. Using a proteomic approach by surface-enhanced laser desorption ionization-mass spectrometry (SELDI-MS) combined with immunological techniques, we provide here evidence that ING1b interacts in vivo with the AR. The interaction was confirmed by co-immunoprecipitation, in vitro GST-pull-down, and quantitative intracellular colocalization analyses. Functionally, ING1b inhibits AR-responsive promoters and endogenous key AR target genes in the human PCa LNCaP cells. Conversely, ING1b knockout (KO) mouse embryonic fibroblasts (MEFs) exhibit enhanced AR activity, suggesting that the interaction with ING1b represses the AR-mediated transcription. Also, data suggest that ING1b expression is downregulated in CRPCa cells compared with androgen-dependent LNCaP cells. Interestingly, its ectopic expression induces cellular senescence and reduces cell migration in both androgen-dependent and CRPCa cells. Intriguingly, ING1b can also inhibit androgen-induced growth in LNCaP cells in a similar manner as AR antagonists. Moreover, ING1b upregulates different cell cycle inhibitors including p27(KIP1), which is a novel target for ING1b. Taken together, our findings reveal a novel corepressor function of ING1b on various AR functions, thereby inhibiting PCa cell growth.

Androgen Receptor Structure, Function and Biology: From Bench to Bedside

The actions of androgens such as testosterone and dihydrotestosterone are mediated via the androgen receptor (AR), a ligand-dependent nuclear transcription factor and member of the steroid hormone nuclear receptor family. Given its widespread expression in many cells and tissues, the AR has a diverse range of biological actions including important roles in the development and maintenance of the reproductive, musculoskeletal, cardiovascular, immune, neural and haemopoietic systems. AR signalling may also be involved in the development of tumours in the prostate, bladder, liver, kidney and lung. Androgens can exert their actions via the AR in a DNA binding-dependent manner to regulate target gene transcription, or in a non-DNA binding-dependent manner to initiate rapid, cellular events such as the phosphorylation of 2(nd) messenger signalling cascades. More recently, ligand-independent actions of the AR have also been identified. Given the large volume of studies relating to androgens and the AR, this review is not intended as an extensive review of all studies investigating the AR, but rather as an overview of the structure, function, signalling pathways and biology of the AR as well as its important role in clinical medicine, with emphasis on recent developments in this field.

Development and Characterization of Cell-Specific Androgen Receptor Knockout Mice

Conditional gene targeting has revolutionized molecular genetic analysis of nuclear receptor proteins, however development and analysis of such conditional knockouts is far from simple, with many caveats and pitfalls waiting to snare the novice or unprepared. In this chapter, we describe our experience of generating and analyzing mouse models with conditional ablation of the androgen receptor (AR) from tissues of the reproductive system and other organs. The guidance, suggestions, and protocols outlined in the chapter provide the key starting point for analyses of conditional-ARKO mice, completing them as described provides an excellent framework for further focussed project-specific analyses, and applies equally well to analysis of reproductive tissues from any mouse model generated through conditional gene targeting.

Androgen receptor promotes abdominal aortic aneurysm development via modulating inflammatory interleukin-1α and transforming growth factor-β1 expression

Sex difference is a risk factor for abdominal aortic aneurysm (AAA) formation yet the reason for male predominance remains unclear. Androgen and the androgen receptor (AR) influence the male sex difference, indicating that AR signaling may affect AAA development. Using angiotensin II–induced AAA in apolipoprotein E null mouse models (82.4% AAA incidence), we found that mice lacking AR failed to develop AAA and aorta had dramatically reduced macrophages infiltration and intact elastic fibers. These findings suggested that AR expression in endothelial cells, macrophages, or smooth muscle cells might play a role in AAA development. Selective knockout of AR in each of these cell types further demonstrated that mice lacking AR in macrophages (20% AAA incidence) or smooth muscle cells (12.5% AAA incidence) but not in endothelial cells (71.4% AAA incidence) had suppressed AAA development. Mechanism dissection showed that AR functioned through modulation of interleukin-1α (IL-1α) and transforming growth factor-β1 signals and by targeting AR with the AR degradation enhancer ASC-J9 led to significant suppression of AAA development. These results demonstrate the underlying mechanism by which AR influences AAA development is through IL-1α and transforming growth factor-β1, and provides a potential new therapy to suppress/prevent AAA by targeting AR with ASC-J9.

Monocyte-endothelial cell interactions in the regulation of vascular sprouting and liver regeneration in mouse

BACKGROUND & AIMS

Regeneration of the hepatic mass is crucial to liver repair. Proliferation of hepatic parenchyma is intimately dependent on angiogenesis and resident macrophage-derived cytokines. However the role of circulating monocyte interactions in vascular and hepatic regeneration is not well-defined. We investigated the role of these interactions in regeneration in the presence and absence of intact monocyte adhesion.

METHODS

Partial hepatectomy was performed in wild-type mice and those lacking the monocyte adhesion molecule CD11b. Vascular architecture, angiogenesis and macrophage location were analyzed in the whole livers using simultaneous angiography and macrophage staining with fluorescent multiphoton microscopy. Monocyte adhesion molecule expression and sprouting-related pathways were evaluated.

RESULTS

Resident macrophages (Kupffer cells) did not migrate to interact with vessels whereas infiltrating monocytes were found adjacent to sprouting points. Infiltrated monocytes colocalized with Wnt5a, angiopoietin 1 and Notch-1 in contact points and commensurate with phosphorylation and disruption of VE-cadherin. Mice deficient in CD11b showed a severe reduction in angiogenesis, liver mass regeneration and survival following partial hepatectomy, and developed unstable and leaky vessels that eventually produced an aberrant hepatic vascular network and Kupffer cell distribution.

CONCLUSIONS

Direct vascular interactions of infiltrating monocytes are required for an ordered vascular growth and liver regeneration. These outcomes provide insight into hepatic repair and new strategies for hepatic regeneration.