Testicular immune cell populations and macrophage polarisation in adult male mice and the influence of altered activin A levels.

Detailed morphological characterization of testicular leukocytes in the adult CX3CR1 gfp/+ transgenic mouse identified two distinct CX3CR1 + mononuclear phagocyte (macrophage and dendritic cell) populations: stellate/dendriform cells opposed to the seminiferous tubules (peritubular), and polygonal cells associated with Leydig cells (interstitial). Using confocal microscopy combined with stereological enumeration of CX3CR1gfp/+ cells established that there were twice as many interstitial cells (68%) as peritubular cells (32%). Flow cytometric analyses of interstitial cells from mechanically-dissociated testes identified multiple mononuclear phagocyte subsets based on surface marker expression (CX3CR1, F4/80, CD11c). These cells comprised 80% of total intratesticular leukocytes, as identified by CD45 expression. The remaining leukocytes were CD3+ (T lymphocytes) and NK1.1+ (natural killer cells). Functional phenotype assessment using CD206 (an anti-inflammatory/M2 marker) and MHC class II (an activation marker) identified a potentially tolerogenic CD206+MHCII+ sub-population (12% of total CD45+ cells). Rare testicular subsets of CX3CR1 +CD11c+F4/80+ (4.3%) mononuclear phagocytes and CD3+NK1.1+ (3.1%) lymphocytes were also identified for the first time. In order to examine the potential for the immunoregulatory cytokine, activin A to modulate testicular immune cell populations, testes from adult mice with reduced activin A (Inhba+/-) or elevated activin A (Inha+/-) were assessed using flow cytometry. Although the proportion of F4/80+CD11b+ leukocytes (macrophages) was not affected, the frequency of CD206+MHCII+cells was significantly lower and CD206+MHCII- correspondingly higher in Inha+/- testes. This shift in expression of MHCII in CD206+ macrophages indicates that changes in circulating and/or local activin A influence resident macrophage activation and phenotype and, therefore, the immunological environment of the testis.

Activin A triggers angiogenesis via regulation of VEGFA and its overexpression is associated with poor prognosis of oral squamous cell carcinoma.

Poor prognosis associated with the dysregulated expression of activin A in a number of malignancies has been related to with numerous aspects of tumorigenesis, including angiogenesis. The present study investigated the prognostic significance of activin A immunoexpression in blood vessels and cancer cells in a number of oral squamous cell carcinoma (OSCC) cases and applied in vitro strategies to determine the impact of activin A on angiogenesis. In a cohort of 95 patients with OSCC, immunoexpression of activin A in both blood vessels and tumor cells was quantified and the association with clinicopathological parameters and survival was analyzed. Effects of activin A on the tube formation, proliferation and migration of human umbilical vein endothelial cells (HUVECs) were evaluated in gain­of­function (treatment with recombinant activin A) or loss­of­function [treatment with activin A­antagonist follistatin or by stable transfection with short hairpin RNA (shRNA) targeting activin A] conditions. Conditioned medium from an OSCC cell line with shRNA­mediated depletion of activin A was also tested. The profile of pro­ and anti­angiogenic factors regulated by activin A was assessed with a human angiogenesis quantitative PCR (qPCR) array. Vascular endothelial growth factor A (VEGFA) and its major isoforms were evaluated by reverse transcription­qPCR and ELISA. Activin A expression in blood vessels demonstrated an independent prognostic value in the multivariate analysis with a hazard ratio of 2.47 [95% confidence interval (CI), 1.30­4.71; P=0.006) for disease­specific survival and 2.09 (95% CI, 1.07­4.08l: P=0.03) for disease­free survival. Activin A significantly increased tubular formation of HUVECs concomitantly with an increase in proliferation. This effect was validated by reduced proliferation and tubular formation of HUVECs following inhibition of activin A by follistatin or shRNA, as well as by treatment of HUVECs with conditioned medium from activin A­depleted OSCC cells. Activin A­knockdown increased the migration of HUVECs. In addition, activin A stimulated the phosphorylation of SMAD2/3 and the expression and production of total VEGFA, significantly enhancing the expression of its pro­angiogenic isoform 121. The present findings suggest that activin A is a predictor of the prognosis of patients with OSCC, and provide evidence that activin A, in an autocrine and paracrine manner, may contribute to OSCC angiogenesis through differential expression of the isoform 121 of VEGFA.

Immunohistochemical localization of inhibin/activin subunits in adult Asian elephant (Elephas maximus) testes.

Immunolocalization of inhibin-α and inhibin/activin ßA and ßB subunits in the testes of Asian elephant was determined. Testicular sections were immunostained with polyclonal antisera against inhibin subunit-α and inhibin/activin ßA and ßB using the avidin-biotin-peroxidase complex method. Positive immunostaining against inhibin-α subunit was strongly present in Sertoli cells, and positive immunostaining for the inhibin/activin ßA and ßB subunits was observed in both Sertoli and Leydig cells. These results indicated that while Sertoli cells are the predominant source of inhibin and activin secretions in the testes of adult male Asian elephant, Leydig cells are a source of activin but not inhibin.

Seminal plasma transforming growth factor-ß, activin A and follistatin fluctuate within men over time.

STUDY QUESTION: Do seminal plasma transforming growth factor-ß (TGFB) cytokines vary within individuals over time, and does this relate to sperm parameters, age or prior abstinence? SUMMARY ANSWER: Activin A and follistatin, and to a lesser extent TGFB1, TGFB2 and TGFB3, vary within individuals over time, in association with duration of abstinence. WHAT IS ALREADY KNOWN: Seminal plasma TGFB cytokines can influence sperm function and reproductive success through interactions with the female reproductive tract after coitus. Over time, individual sperm parameters fluctuate considerably. Whether seminal fluid TGFB cytokines vary similarly, and the determinants of any variance, is unknown. STUDY DESIGN, SIZE, DURATION: Between two and seven semen samples were collected from each of 14 fertile donors at 6-10 week intervals over the course of 12 months, then seminal plasma cytokines and sperm parameters were measured. PARTICIPANTS/MATERIALS, SETTING AND METHOD: The concentrations and total amounts per ejaculate of TGFB1, TGFB2, TGFB3, activin A and follistatin were determined using commercial assays. Sperm parameters were assessed according to WHO IV standards. Mixed model analysis was utilised to determine the relative contribution of between- and within-individual factors to the variance. Relationships between cytokines and sperm parameters, as well as effect of age and duration of abstinence, were investigated by correlation analysis. MAIN RESULTS AND THE ROLE OF CHANCE: Within-individual variability contributed to the total variance for all cytokines and sperm parameters, and was a stronger determinant than between-individual variability for activin A and follistatin as well as for total sperm concentration and sperm motility. Positive correlations between each of the three TGFB isoforms, and activin and follistatin, suggest co-regulation of synthesis. Duration of abstinence influenced total content of TGFB1, TGFB2, activin A and follistatin. TGFB1 correlated inversely with age. LIMITATIONS, REASONS FOR CAUTION: A limited number of donors from a single clinic were investigated. Clinical information on BMI, nutrition, smoking and other lifestyle factors was unavailable. Further studies are required to determine whether the findings can be generalised to larger populations and different ethnicities. WIDER IMPLICATIONS OF THE FINDINGS: These data reveal substantial variation over time in seminal fluid cytokines and indicate that repeated analyses are required to gain precise representative data on an individual's status. Within-individual variation in seminal fluid components should be taken into account when investigating seminal fluid cytokines. STUDY FUNDING/COMPETING INTERESTS: This study was supported by grants from the National Health and Medical Research Council of Australia, ID453556 and APP1041332. The authors have no competing interests to disclose.

Activin A and follistatin during the oestrous cycle and early pregnancy in ewes.

The activin pathway has been postulated to be involved in regulation of multiple reproductive processes important for survival of the conceptus. These processes include luteinisation of the follicular cells and thus function of the corpus luteum, early embryo development and uterine function including implantation of the conceptus. Therefore, the aim of the current study was to determine whether the concentrations of activin A and follistatin (FST), an activin-binding protein, differed between ewes with a lifetime history of enhanced or reduced embryonic survival (ES). The mRNAs encoding FST and activin A (inhibin beta A subunit; INHBA) were present in the uterus and abundant in the uterine luminal or glandular epithelia by day 18 of gestation. A peak of activin A was observed in the systemic circulation around the time of oestrus, and activin A concentrations were elevated in animals with reduced ES during the oestrous cycle and early gestation. Concentrations of activin A in uterine fluid were approximately twofold greater on day 16 of gestation in ewes with reduced ES compared to those with enhanced ES. No consistent differences in FST were observed between these groups. Treatment of luteinising ovine granulosa cells with activin A in vitro suppressed progesterone secretion providing evidence of a potential pathway whereby increased concentrations of activin A may decrease ES.

Myostatin, follistatin and activin type II receptors are highly expressed in adenomyosis.

OBJECTIVE: To evaluate the expression pattern of activins and related growth factor messenger RNA (mRNA) levels in adenomyotic nodules and in their endometrium. DESIGN: Prospective study. SETTING: University hospital. PATIENT(S): Symptomatic premenopausal women scheduled to undergo hysterectomy for adenomyosis. INTERVENTION(S): Samples from adenomyotic nodules and homologous endometria were collected. Endometrial tissue was also obtained from a control group. MAIN OUTCOME MEASURE(S): Quantitative real-time polymerase chain reaction (PCR) analysis and immunohistochemical localization of activin-related growth factors (activin A, activin B, and myostatin), binding protein (follistatin), antagonists (inhibin-α, cripto), and receptors (ActRIIa, ActRIIb) were performed. RESULT(S): Myostatin mRNA levels in adenomyotic nodule were higher than in eutopic endometrium and myostatin, activin A, and follistatin concentrations were higher than in control endometrium. No difference was observed for inhibin-α, activin B, and cripto mRNA levels. Increased mRNA levels of ActRIIa and ActRIIb were observed in adenomyotic nodules compared with eutopic endometrium and control endometrium. Immunofluorescent staining for myostatin and follistatin confirmed higher protein expression in both glands and stroma of patients with adenomyosis than in controls. CONCLUSION(S): The present study showed for the first time that adenomyotic tissues express high levels of myostatin, follistatin, and activin A (growth factors involved in proliferation, apoptosis, and angiogenesis). Increased expression of their receptors supports the hypothesis of a possible local effect of these growth factors in adenomyosis. The augmented expression of ActRIIa, ActRIIb, and follistatin in the endometrium of these patients may play a role in adenomyosis-related infertility.

Expression of Cripto-1 gene protein and Activin-A in human lung adenocarcinoma tissue.

To research the expression in human lung adenocarcinoma tissue of Cripto-1 (teratocarcinoma derived growth factor-1) gene protein and Activin-A gene protein, and explore the relationship and clinical significance between the two gene protein and clinical pathological characteristic of lung adenocarcinoma. This study had applied the immunohistochemical method to detect the 188 cases of lung adenocarcinoma and expression of Cripto-1 protein and Activin-A protein in 100 cases of normal lung tissue. Then, analysis the relationship between these two-gene protein and clinical lung adenocarcinoma histopathological features, and inherent correlation between these two genes. The positive expression rate of Cripto-1 protein in lung adenocarcinoma tissue was significantly higher in normal lung tissue, while, the positive expression rate of Activin-A protein in lung adenocarcinoma tissue was significantly lower than in normal lung tissue. The high expression of Cripto-1 and low expression of Activin-A was closely related (each P<0.05) to the TNM staging of lung adenocarcinoma, lymph node metastasis and the main pathological tissue staging of lung adenocarcinoma. And the correlation analysis showed that it was negative correlation for the expression of Activin-A protein and Cripto-1 protein in lung adenocarcinoma. The over expression of Cripto-1 and the expression lack of Activin-A were correlated with the occurrence, development, metastasis and malignant degree of lung adenocarcinoma.

Upregulation of alveolar levels of activin B, but not activin A, in lungs of west highland white terriers with idiopathic pulmonary fibrosis and diffuse alveolar damage.

Activins, cytokines belonging to the transforming growth factor-ß superfamily, have an important role in inflammation and fibrosis. Activin A has been suggested to participate in the pathophysiology of human idiopathic pulmonary fibrosis (IPF), but studies on the role of activin B are sparse. Canine IPF (CIPF) is an incurable interstitial lung disease occurring particularly in West Highland white terriers (WHWTs). During the disease course there are acute exacerbations (AEs) and the condition has a poor prognosis. Microscopically, AEs of CIPF are characterized by diffuse alveolar damage, which is also a key feature of acute respiratory distress syndrome (ARDS). The aim of this study was to study expression of activin A and B in lung tissue of WHWTs with CIPF and WHWTs with CIPF and concurrent AE, and dogs of various breeds with ARDS and to compare these findings with those of healthy WHWTs. In addition, western blot analysis of activin B from bronchoalveolar lavage fluid (BALF) from WHWTs with CIPF and healthy WHWTs was conducted. Activin B, but not activin A, was strongly expressed in the altered alveolar epithelium in the lungs of WHWTs with CIPF as well as in the lungs of dogs with ARDS. Activin B was detected in the BALF of WHWTs with CIPF, most notably in samples from dogs with AE, but activin B was not detected in BALF from healthy WHWTs. These findings suggest that activin B may be part of the pathophysiology of CIPF and might act as a marker of alveolar epithelial damage.

Growth factor expression pattern of homologous feeder layer for culturing buffalo embryonic stem cell-like cells.

The present study examined the expression profile of buffalo fetal fibroblasts (BFF) used as a feeder layer for embryonic stem (ES) cell-like cells. The expression of important growth factors was detected in cells at different passages. Mitomycin-C inactivation increased relative expression levels of ACTIVIN-A, TGF-ß1, BMP-4 and GREMLIN but not of fibroblast growth factor-2 (FGF-2). The expression level of ACTIVIN-A, transforming growth factor-ß1 (TGF-ß1), bone morphogenetic protein-4 (BMP-4) and FGF-2 was similar in buffalo fetal fibroblast (BFF) cultured in stem cell medium (SCM), SCM+1000IU mL(-1) leukemia inhibitory factor (LIF), SCM+5 ngmL(-1) FGF-2 or SCM+LIF+FGF-2 for 24 h whereas GREMLIN expression was higher in FGF-2-supplemented groups. In spent medium, the concentration of ACTIVIN-A was higher in FGF-2-supplemented groups whereas that of TGF-ß1 was similar in SCM and LIF+FGF-2, which was higher than when either LIF or FGF-2 was used alone. Following culture of ES cell-like cells on a feeder layer for 24 h, the TGF-ß1 concentration was higher with LIF+FGF-2 than with LIF or FGF-2 alone which, in turn, was higher than that in SCM. In the LIF+FGF-2 group, the concentration of TGF-ß1 was lower and that of ACTIVIN-A was higher in spent medium at 24 h than at 48 h of culture. These results suggest that BFF produce signalling molecules that may help in self-renewal of buffalo ES cell-like cells.

Anti-inflammatory therapy in an ovine model of fetal hypoxia induced by single umbilical artery ligation.

Perinatal morbidity and mortality are significantly higher in pregnancies complicated by chronic hypoxia and intrauterine growth restriction (IUGR). Clinically, placental insufficiency and IUGR are strongly associated with a fetoplacental inflammatory response. To explore this further, hypoxia was induced in one fetus in twin-bearing pregnant sheep (n=9) by performing single umbilical artery ligation (SUAL) at 110 days gestation. Five ewes were administered the anti-inflammatory drug sulfasalazine (SSZ) daily, beginning 24h before surgery. Fetal blood gases and inflammatory markers were examined. In both SSZ- and placebo-treated ewes, SUAL fetuses were hypoxic and growth-restricted at 1 week (P<0.05). A fetoplacental inflammatory response was observed in SUAL pregnancies, with elevated pro-inflammatory cytokines, activin A and prostaglandin E(2). SSZ did not mitigate this inflammatory response. It is concluded that SUAL induces fetal hypoxia and a fetoplacental inflammatory response and that SSZ does not improve oxygenation or reduce inflammation. Further studies to explore whether alternative anti-inflammatory treatments may improve IUGR outcomes are warranted.

Serum activin A levels are lower in tubal than intrauterine spontaneously conceived pregnancies.

OBJECTIVE: To measure serum activin A levels together with progesterone and hCG, in women with overt clinical signs and symptoms of ectopic pregnancy (EP) and, in gestational age-matched intrauterine pregnancy (IUP). DESIGN: Retrospective case-control study. SETTING: Department of Pediatrics, Obstetrics and Reproductive Medicine, Section of Obstetrics and Gynecology, University of Siena, Siena, Italy. POPULATION: The study group was composed by 30 women with an EP; the control group was composed by 30 women with a sonographic evidence of a single spontaneous IUP. METHODS: Clinical examination; transvaginal ultrasound scan; hCG, progesterone and activin-A measurements; laparoscopy; uterine curettage; histological examination. MAIN OUTCOME MEASURE: Pregnancy outcome; sensitivity and specificity of hCG, progesterone, and activin A for EP. RESULTS: Serum hCG levels did not differ significantly between tubal EP and IUP, while P concentrations were significantly (P < 0.001) lower in tubal EP than IUP. Serum levels of activin A were significantly (P < 0.0001) lower in tubal EP than in IUP and, at the cutoff 0.43 ng/mL achieved a sensitivity of 96.7% and a specificity of 100% for EP. CONCLUSION: Activin A secretion in EP is reduced and measurement of its serum levels may have the potential clinical advantage to signal the presence of EP.

Potential biomarkers of temporomandibular joint disorders.

PURPOSE: The purpose of this study was to identify protein markers present in subjects with temporomandibular joint disorders (TMDs) and clicking compared with the levels in controls. MATERIALS AND METHODS: This was a pilot case-control study, and we report the preliminary results. Samples of joint aspirate collected from patients with TMDs and controls who had undergone surgery for a problem other than TMDs were analyzed using isobaric tags for relative and absolute quantitation (iTRAQ) and biotin-labeled-based protein arrays. The data obtained from these techniques were used to identify the proteins of interest, which were then quantitated using enzyme-linked immunosorbent assay (ELISA). The patient samples studied included joint aspirate collected clinically from the controls and patients and included samples from both the right and the left sides of each patient with a TMD. RESULTS: The 8 TMJ aspirate samples from 6 subjects included 5 aspirate samples from 4 patients and 3 from 2 controls. The greatest standardized protein concentration of endocrine gland-derived vascular endothelial growth factor/prokineticin-1 (EG-VEGF/PK1) and D6 was found in both joints of the controls compared with the levels from the joints of the patients. With 1 exception, the standardized protein concentration was significantly lower in the patients than in the controls. The lower levels of EG-VEGF/PK1 and D6 in the patients compared with the controls suggest that these cytokines might be possible biomarkers for TMDs. CONCLUSION: In the present pilot study, greater levels of EG-VEGF/PK1 and D6 were found in the controls than in the patients with TMDs. Proteomic analysis of the proteins present in the diseased joints compared with those in the controls might help to identify proteins present when pain or degeneration of the joint occurs. The proteomic information might be useful in the development of future therapies.

Immunohistochemical localization of inhibin and activin subunits, activin receptors and Smads in ovarian endometriosis.

We previously reported that activin A, not inhibin, was localized to endometrial tissues, and that the endometrium might be a major source of activin A during the menstrual cycle, using an immunohistochemical method. However, there are few detailed reports concerning the expression of inhibin subunits, activin receptors and Smad proteins in the ectopic endometrial tissues of endometriosis. In this study, our purpose was to evaluate the immunohistochemical localization of inhibin alpha-, betaA-subunits, activin A, activin receptor, and Smad proteins in ovarian endometriosis. Tissue samples from ovarian endometriosis were obtained from 13 women. Normal endometrial tissues were obtained during the proliferative phase from 5 premenopausal women without endometriosis who were undergoing a hysterectomy for the treatment of uterine cervical intraepithelial neoplasia 3. We examined the immunohistochemical localization of inhibin/activin alpha-, betaA-subunit, activin A, activin receptors types IA, IB, IIA, IIB, Smad2, Smad3 and Smad4 using an avidin-biotin-peroxidase complex technique. No immunostaining for the alpha-subunit of inhibin was observed in ovarian endometriosis and the normal endometrium. Positive immunostaining for the betaA-subunit of inhibin, activin A, activin receptors types IA, IB, IIA, IIB, Smad2, Smad3 and Smad4 was observed in ovarian endometriosis and the normal endometrium. In conclusion, these results suggest that activin A, but not inhibins, is produced by ovarian endometriosis and the normal endometrium, and that the activin signal transduction system exists in both ovarian endometriosis and the normal endometrium.

Analysis of activin/TGFB-signaling modulators within the normal and dysfunctional adult human testis reveals evidence of altered signaling capacity in a subset of seminomas.

Activin is a pleiotropic growth factor belonging to the transforming growth factor-beta (TGFB) superfamily of signaling molecules. Regulated activin signaling is known to influence several steps in rodent male gamete differentiation. TGFB ligand isoforms, TGFB1-B3, also influence germ cell survival in the rodent testis at the onset of spermatogenesis and around the time of puberty. Given the importance of regulated activin and TGFB signaling in testis development and function, we sought to investigate the cellular production sites of activin/TGFB-signaling modulators in normal and dysfunctional adult human testes samples. Signaling transducers phosphorylated SMAD2/3, and signaling modulators SMAD6, MAN-1, inhibin alpha (INHA), and beta-glycan were detected in Bouins fixed, paraffin-embedded adult human testis sections using immunohistochemistry. Additional samples examined were from testicular cancer patients and from normal men subjected to gonadotropin suppression with androgen-based contraceptives. Our findings identify distinct differences between normal and gonadotropin-deprived human testis in the expression and cellular localization of activin/TGFB-signaling modulators. The presence of a nuclear phosphorylated SMAD2/3 signal in all analyzed seminoma specimens indicated active activin/TGFB signaling. Moreover, a subset of seminoma specimens exhibited selective enhanced expression of beta-glycan (4 out of 28 seminoma tumors), INHA (6 out of 28), and MAN-1 (6 out of 28), highlighting potential functional differences between individual tumors in their capacity to regulate activin/TGFB signaling. Within the heterogenous nonseminomas, expression of signaling modulators was variable and reflected the degree of somatic differentiation. Thus, synthesis of activin and TGFB-signaling modulators may be affected by spermatogenic disruption and altered hormone levels in the testis.

Seasonal changes in spermatogenesis and immunolocalization of inhibin/activin subunits in the wild male ground squirrel (Citellus dauricus Brandt).

The objective of this study was to investigate the seasonal changes in spermatogenesis and the immunolocalization of the inhibin alpha and inhibin/activin (betaA and betaB) subunits during the breeding and non-breeding seasons in the wild male ground squirrel. The testicular weight and size and seminiferous tubule diameter were measured, and histological observations of testes were performed. The sections of the testes were immunostained by the avidin-biotin-peroxidase complex method (ABC) using polyclonal antisera raised against porcine inhibin alpha, inhibin/activin betaA and inhibin/activin betaB during the breeding and non-breeding seasons. There were marked variations in testicular weight and size and seminiferous tubule diameter between the breeding and non-breeding seasons, and all types of spermatogenic cells, including spermatozoa, were found in the breeding season. In addition, immunoreactivity was also detected for the inhibin alpha, betaA and betaB subunits in Sertoli and Leydig cells during the breeding season, but immunostaining was only present for the inhibin alpha and inhibin/activin betaB subunits in Sertoli cells during the non-breeding season. These results suggest that seasonal changes in testicular weight and size and seminiferous tubule diameter of wild ground squirrels are correlated with changes in spermatogenesis, and the cellular localization of the inhibin/activin subunits showed season related changes in the breeding and non-breeding seasons.

Correlations between anti-müllerian hormone, inhibin B, and activin A in follicular fluid in IVF/ICSI patients for assessing the maturation and developmental potential of oocytes.

OBJECTIVE: The objective of the present study was to evaluate the correlation between anti-müllerian hormone (AMH), inhibin B, and activin A in follicular fluid from patients receiving treatment with in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), to identify a parameter to assess the maturation and developmental potential of oocytes. - MATERIALS AND METHODS: AMH, inhibin B, and activin A were measured in follicular fluid from 27 patients undergoing IVF/ICSI treatment for male-factor infertility, tubal occlusion, endometriosis, or anovulation. The values were correlated with the serum estradiol level, the numbers and maturation of the oocytes, and the outcome of IVF/ICSI. - RESULTS: A positive correlation was found between AMH in follicular fluid and the number of oocytes retrieved. High inhibin B levels in follicular fluid and high serum E subset2 levels indicated a normal ovarian response to stimulation, corresponding to the oocyte numbers, while low inhibin B and 17-beta-estradiol (E subset2) levels indicated poor responders to stimulation. An activin A/inhibin B ratio of less than 1 and very high inhibin B levels correlated with large numbers of oocytes, while a ratio of 1-2 and high inhibin levels correlated with regular numbers of oocytes. An activin/inhibin ratio of more than 3 and low inhibin levels were found in poor responders. Pregnancies occurred predominantly in the group with a normal or high response. Patients with elevated ratios for 17-beta-estradiol/AMH, oocyte numbers/AMH, and metaphase II oocyte numbers/AMH had the best chances of becoming pregnant, indicating an inverse correlation between AMH and the maturation and developmental potential of the oocytes. - CONCLUSIONS: In IVF/ICSI patients, a positive correlation was found between AMH, inhibin B, and the activin A/inhibin B ratio in follicular fluid, on the one hand; and between serum 17-beta-estradiol levels and the numbers of oocytes retrieved, on the other. The activin A/inhibin B ratio correlated with the number of oocytes retrieved. The ratio for 17-beta-estradiol, oocyte numbers, and metaphase II oocytes relative to AMH indicated the best developmental potential, and it can therefore be assumed that there is a negative correlation between AMH levels and the maturation and quality of oocytes.

Regulated production of activin A and inhibin B throughout the cycle of the seminiferous epithelium in the rat.

Production and regulation of activin A and inhibin B during the cycle of the seminiferous epithelium were investigated in adult rats. Immunohistochemistry localised the activin beta(A)-subunit to the Sertoli cell cytoplasm, with much weaker expression in spermatocytes and spermatids. Both activin A and inhibin B, measured by ELISA were secreted by, seminiferous tubule fragments over 72 h in culture. Activin A was secreted in a cyclic manner with peak secretion from tubules isolated at stage VIII. Tubules collected during stage VI produced the least activin A. Inhibin B secretion was highest from stage IX-I tubules and lowest from stage VII tubules. Addition of interleukin-1beta (IL-1beta) had relatively little effect on activin A or inhibin B secretion in culture. In contrast, the peak secretion of activin A by stage VIII tubules was blocked by co-incubation with an excess of human recombinant IL-1 receptor antagonist, whereas inhibin B secretion increased slightly. Dibutyryl cAMP stimulated activin A secretion by late stage VII and VIII tubules and stimulated inhibin B across all stages. These data indicate that activin A and inhibin B are cyclically regulated within the seminiferous epithelium, with endogenous IL-1 (presumably IL-1alpha produced by the Sertoli cells), responsible for a peak of activin A production subsequent to sperm release at stage VIII. These data provide direct evidence that production of activin A and inhibin B by the Sertoli cell is locally modulated by IL-1alpha , in addition to FSH/cAMP, under the influence of the developing spermatogenic cells.

Activin A concentrations in human cerebrospinal fluid are age-dependent and elevated in meningitis.

OBJECTIVE: Activin A, and its binding protein, follistatin (FS), are expressed in the central nervous system (CNS). We have previously shown elevated concentrations of FS in the cerebrospinal fluid (CSF) of patients with meningitis and increased concentrations of activin A in the CSF of rabbits with bacterial meningitis. METHODS: We measured CSF and serum concentrations of activin A and FS in normal subjects and in patients with various neurological diseases using previously validated immunoassays specific for activin A or FS. RESULTS: In healthy persons, serum concentrations of both activin A and FS were age-dependent. In CSF, concentrations of activin A ranged from 0.03 to 0.33 ng/ml and were strongly correlated with age in both sexes, whereas FS CSF concentrations were below the assay detection limit in most of the patients. Activin A concentrations in CSF of patients with various neurological diseases, including meningitis, chronic inflammatory CNS diseases, neurodegenerative diseases, tumors in the CNS, cerebral ischemia, intracerebral/subarachnoid hemorrhages, subdural hemorrhages and epileptic seizures, were compared with age- and sex-matched control patients. The comparisons revealed significantly elevated concentrations of activin A in patients with meningitis (P=0.017). Serum concentrations of activin A or FS were not affected by any of the neurological diseases examined. CONCLUSIONS: Our results show for the first time that in normal subjects concentrations of activin A in CSF are correlated with age, and furthermore, that activin A CSF concentrations are elevated in patients with meningitis. The latter underlines a role for activin A in acute inflammatory processes within the CNS.

The autocrine effect of activin A on human ovarian clear cell adenocarcinoma cells.

The functions of activin, a member of TGF-beta superfamily, in ovarian clear cell adenocarcinoma remain unsolved, although we recently found that inhibin betaA-subunit, activin A, activin receptor type IA, type IB, type IIA, type IIB, Smad2, Smad3 and Smad4 were localized in tumor cells of the ovarian clear cell adenocarcinoma tissue by immunohistochemistry. In the present study, in order to investigate the role of activin concerning cell growth in ovarian clear cell adenocarcinoma cells, we determined the production of activin A and inhibin A, and the expression of activin receptors and Smads using the human ovarian clear cell adenocarcinoma cell line JHOC-5. Moreover, we examined the effects of activin A on the activation of activin signaling pathway and on the proliferation in JHOC-5 cells. We detected a measurable amount of activin A in the culture medium of JHOC-5 cells, although inhibin A was not detected. The expression of activin receptor type IA, IB, IIA, IIB, Smad2, Smad3 and Smad4 was observed in JHOC-5 cells. Activin A induced a significant increase in proliferation of JHOC-5 cells compared with the untreated control. On the other hand, activin A did not affect the growth of JHOC-5 cells and no statistically significant difference was observed in the presence of follistatin which is a specific binding protein of activin. Phosphorylated Smad2, an activated form of Smad2, was detected both in treated JHOC-5 cells and in untreated cells by activin A. Activin A significantly increased the expression of phosphorylated Smad2 in JHOC-5 cells. Therefore, it is possible that activin has autocrine roles in tumor growth of ovarian clear cell adenocarcinoma cells.