Thyroid hormone modulates androgen and oestrogen receptor content in the Sertoli cells of peripubertal rats

1996 ◽  
Vol 148 (1) ◽  
pp. 43-50 ◽  
Author(s):  
M L Panno ◽  
D Sisci ◽  
M Salerno ◽  
M Lanzino ◽  
V Pezzi ◽  
...  
Keyword(s):  
Sertoli Cells ◽  
Oestrogen Receptor ◽  
Age Groups ◽  
Strong Relationship ◽  
Inhibitory Influence ◽  
Aromatase Activity ◽  
Severe Impairment ◽  
Cellular Compartments

Abstract A possible role of tri-iodothyronine (T3) on the interplay between testicular steroids and Sertoli cells has been investigated on the basis of previous findings demonstrating a direct inhibitory influence of T3 on aromatase activity and oestradiol production in peripuberal Sertoli cells. In this context, the present study was focused on the effects of T3 on oestrogen receptor (ER) and androgen receptor (AR) contents in the cytosol and nucleus of Sertoli cells isolated from 2-, 3- and 4-week-old euthyroid, hypothyroid and hypothyroid treated rats. Hypothyroidism was induced by the oral administration of 0·025% methimazole (MMI) from birth until the rats were killed at 2, 3 and 4 weeks of age. Half of the MMI-treated animals were injected i.p. with l-tri-iodothyronine (T3; 3 μg/100 g body weight) during the last week before death. Sertoli cells from all groups were initially cultured under basal conditions for the first 24 h and subsequently in the presence of testosterone with or without T3 for an additional 24 h. Hypothyroidism was associated with severe impairment of body as well as testicular growth. Euthyroid ERs showed an elevated Kd (0·76 nm) which was similar in the different age groups investigated. The in vitro addition of T3 or testosterone induced a decrease in ER content and this decrease was greater after exposure to both hormones. In 2- and 3-week-old hypothyroid rats, ER content was markedly increased and was reversed in euthyroid rats when T3 was given in vivo. When ERs were assayed in the Sertoli cell nucleus and cytoplasm of 2- and 3-week-old animals, a strong relationship in ER content in the two cellular compartments was observed. Neither of the hormones tested seemed to affect the AR content in the nucleus significantly, while the in vitro addition of testosterone or T3 or both hormones together augmented the ARs in the cytosol to a greater extent, resulting in an increase in their total (cytosolic and nuclear) content in the cells. The present data suggest that T3 down-regulates ERs and up-regulates ARs in peripuberal Sertoli cells. The additive effect of testosterone and T3 in up-regulating ARs could possibly involve a role for T3 in influencing the androgen responsiveness of the Sertoli cells during spermatogenesis. Journal of Endocrinology (1996) 148, 43–50

Influence of thyroid hormone on androgen metabolism in peripuberal rat Sertoli cells

1994 ◽  
Vol 140 (3) ◽  
pp. 349-355 ◽  
Author(s):  
M L Panno ◽  
E Beraldi ◽  
V Pezzi ◽  
M Salerno ◽  
G De Luca ◽  
...  
Keyword(s):  
Body Weight ◽  
Thyroid Hormone ◽  
Sertoli Cells ◽  
Testosterone Metabolism ◽  
Androgen Metabolism ◽  
Functional Maturation ◽  
Severe Impairment ◽  
Old Rats

Abstract The aim of the present study was to investigate the influence of thyroid hormones on androgen metabolism in Sertoli cells isolated from 3- and 4- week-old rats. Hypothyroidism was induced by the oral administration of 0·025% methimazole (MMI) from birth until the rats were killed at 3 and 4 weeks of age. Half of the MMI-treated animals were injected i.p. with l-tri-iodothyronine (T3 3 μg/100 g body weight) during the last week before death. Sertoli cells from all groups were initially cultured under basal conditions for the first 24 h and subsequently in the presence of testosterone with or without T3 for an additional 24 h. Hypothyroidism was associated with severe impairment of body as well as testicular growth. Indeed, body and testicular weights were similar in 4-week-old hypothyroid animals to those in 3-week-old control rats. Testosterone metabolism in Sertoli cells isolated from 3- and 4-week-old hypothyroid rats was mainly expressed by the lowering of 5α-dihydrotestosterone + androstane 3α, 17β–diol and an enhanced formation of 5α-reduced steroids with poor androgenic properties (e.g. 5α–androstane, 3, 17α-dione (androstanedione), 5α–androstan, 3-ol-17-one (androsterone)). Treatment of the same group of animals with T3 in vivo and in vitro did not influence the pattern of 5α–reductase steroids substantially. The most striking finding in the Sertoli cells of 3-week-old hypothyroid rats was the dramatic enhancement of oestradiol formation which persisted to a lesser extent 1 week later. Oestradiol formation was greatly decreased by the addition of T3 in vivo and in vitro in hypothyroid animals. These results suggest that T3 might influence androgen metabolism during the functional maturation of Sertoli cells. Journal of Endocrinology (1994) 140, 349–355

BMP2 Is Required for Postnatal Maintenance of Osteochondral Tissues of the Temporomandibular Joint

Cartilage ◽  
2020 ◽  
pp. 194760352098015
Author(s):  
Mara H. O’Brien ◽  
Eliane H. Dutra ◽  
Shivam Mehta ◽  
Po-Jung Chen ◽  
Sumit Yadav
Keyword(s):  
Age Groups ◽  
Mandibular Condyle ◽  
Bone Morphogenetic Protein 2 ◽  
Matrix Synthesis ◽  
Cartilage Growth ◽  
Chondrocyte Proliferation ◽  
Conditional Deletion ◽  
Morphogenetic Protein

Objective Bone morphogenetic protein 2 (BMP2) plays important roles in cartilage growth and development. Paradoxically, elevated levels of BMP2 leads to hypertrophic differentiation and osteoarthritis of cartilage. We examined the in vivo loss of BMP2 in cells expressing aggrecan of the mandibular condyle and knee. Design Three-week-old BMP2 flox/flox- CreER-positive mice and their Cre-negative littermates were treated with tamoxifen and raised until 3 or 6 months. We also investigated the direct effects of BMP2 on chondrocytes in vitro. Cells from the mandibular condyle of mice were treated with recombinant human BMP2 (rhBMP2) or rhNoggin (inhibitor of BMP2 signaling). Results Conditional deletion of BMP2 caused breakage of the cartilage integrity in the mandibular condyle of mice from both age groups, accompanied by a decrease in cartilage thickness, matrix synthesis, mineralization, chondrocyte proliferation, and increased expression of degeneration markers, while the effects at articular cartilage were not significant. In vitro results revealed that rhBMP2 increased chondrocyte proliferation, mineralization, and differentiation, while noggin induced opposite effects. Conclusions In conclusion, BMP2 is essential for postnatal maintenance of the osteochondral tissues of the mandibular condyle.

scholarly journals Ezrin is an Actin Binding Protein That Regulates Sertoli Cell and Spermatid Adhesion During Spermatogenesis

Endocrinology ◽  
2014 ◽  
Vol 155 (10) ◽  
pp. 3981-3995 ◽  
Author(s):  
N. Ece Gungor-Ordueri ◽  
Elizabeth I. Tang ◽  
Ciler Celik-Ozenci ◽  
C. Yan Cheng
Keyword(s):  
Sertoli Cell ◽  
Sertoli Cells ◽  
Adherens Junction ◽  
Actin Binding ◽  
Permeability Barrier ◽  
Tight Junction Permeability ◽  
Residual Bodies ◽  
Cell Interface

Abstract During spermatogenesis, the transport of spermatids and the release of sperms at spermiation and the remodeling of the blood-testis barrier (BTB) in the seminiferous epithelium of rat testes require rapid reorganization of the actin-based cytoskeleton. However, the mechanism(s) and the regulatory molecule(s) remain unexplored. Herein we report findings that unfold the functional significance of ezrin in the organization of the testis-specific adherens junction at the spermatid-Sertoli cell interface called apical ectoplasmic specialization (ES) in the adluminal compartment and the Sertoli cell-cell interface known as basal ES at the BTB. Ezrin is expressed at the basal ES/BTB in all stages, except from late VIII to IX, of the epithelial cycle. Its knockdown by RNA interference (RNAi) in vitro perturbs the Sertoli cell tight junction-permeability barrier via a disruption of the actin microfilaments in Sertoli cells, which in turn impeded basal ES protein (eg, N-cadherin) distribution, perturbing the BTB function. These findings were confirmed by a knockdown study in vivo. However, the expression of ezrin at the apical ES is restricted to stage VIII of the cycle and limited only between step 19 spermatids and Sertoli cells. A knockdown of ezrin in vivo by RNAi was found to impede spermatid transport, causing defects in spermiation in which spermatids were embedded deep inside the epithelium, and associated with a loss of spermatid polarity. Also, ezrin was associated with residual bodies and phagosomes, and its knockdown by RNAi in the testis also impeded the transport of residual bodies/phagosomes from the apical to the basal compartment. In summary, ezrin is involved in regulating actin microfilament organization at the ES in rat testes.

Adrenocortical function in aging exercise-trained rats

1977 ◽  
Vol 43 (5) ◽  
pp. 839-843 ◽  
Author(s):  
J. A. Severson ◽  
R. D. Fell ◽  
J. G. Tuig ◽  
D. R. Griffith
Keyword(s):  
Age Groups ◽  
Plasma Corticosterone ◽  
Treadmill Running ◽  
Adrenocortical Function ◽  
Elevated Plasma ◽  
Corticosterone Concentration ◽  
Relationship Of ◽  
The Relationship

Plasma corticosterone concentrations and in vitro adrenal secretion of corticosterone were determined in exercise-trained rats. Rats, 100, 200, and 300 days of age, were trained for a 10-wk period by treadmill running. Following the training program, rats were subjected to an acute bout of swimming. Acute swimming elevated plasma corticosterone concentrations in all age groups. At 170 days of age, the plasma corticosterone concentration following swimming was higher in exercise-trained rats than in controls. The opposite was true of acutely swum rats at 270 and 370 days of age. Acute swimming elevated the in vitro adrenal gland response to adrenocorticotropic hormone stimulation in control rats at all ages and in trained rats at 170 days of age. The in vivo relationship of epinephrine and the pituitary adrenal system is suggested as a mechanism which could have caused this response. The relationship of secretion rates to plasma corticosterone concentrations indicated that extra-adrenal mechanisms, such as decreased turnover, were also responsible for the elevated plasma corticosterone levels observed in response to acute swimming.

scholarly journals Hexarelin exerts neuroprotective and antioxidant effects against hydrogen peroxide-induced toxicity through the modulation of MAPK and PI3K/Akt patways in Neuro-2A cells

2020 ◽  
Author(s):  
Ramona Meanti ◽  
Laura Rizzi ◽  
Elena Bresciani ◽  
Laura Molteni ◽  
Vittorio Locatelli ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Hydrogen Peroxide ◽  
Apoptotic Cell ◽  
Neuroblastoma Cell ◽  
Neuroblastoma Cell Line ◽  
Inhibitory Influence ◽  
No Production ◽  
Mrna Levels

AbstractHexarelin, a synthetic hexapeptide, protects cardiac and skeletal muscles by inhibiting apoptosis, both in vitro and in vivo. Moreover, evidence suggests that hexarelin could have important neuroprotective bioactivity.Oxidative stress and the generation of free radicals has been implicated in the etiologies of several neurodegenerative diseases, including amyotrophic lateral sclerosis, Parkinson’s disease, Alzheimer’s disease, Huntington’s disease and multiple sclerosis. In addition to direct oxidative stress, exogenous hydrogen peroxide (H2O2) can penetrate biological membranes and enhance the formation of other reactive oxygen species.The aim of this study was to examine the inhibitory influence of hexarelin on H2O2-induced apoptosis in Neuro-2A cells, a mouse neuroblastoma cell line. Our results indicate that H2O2 reduced the viability of Neuro-2A cells in a dose-related fashion. Furthermore, H2O2 induced significant changes in the morphology of Neuro-2A cells, reflected in the formation of apoptotic cell bodies, and an increase of nitric oxide (NO) production. Hexarelin effectively antagonized H2O2 oxidative damage to Neuro-2A cells as indicated by improved cell viability, normal morphology and reduced nitrite (NO2−) release. Hexarelin treatment of Neuro-2A cells also reduced mRNA levels of caspases−3 and −7 and those of the pro-apoptotic molecule Bax; by contrast, hexarelin treatment increased anti-apoptotic Bcl-2 mRNA levels. Hexarelin also reduced MAPKs phosphorylation induced by H2O2 and concurrently increased p-Akt protein expression.In conclusion, our results identify several neuroprotective and anti-apoptotic effects of hexarelin. These properties suggest that further investigation of hexarelin as a neuroprotective agent in an investigational and therapeutic context are merited.

scholarly journals An in vitro ovarian explant culture system to examine sex change in a hermaphroditic fish

2020 ◽  
Author(s):  
Alexander Goikoetxea ◽  
Erin L Damsteegt ◽  
Erica V Todd ◽  
Andrew McNaughton ◽  
Neil J Gemmell ◽  
...  
Keyword(s):  
Culture System ◽  
Sex Change ◽  
Explant Culture ◽  
Culture Technique ◽  
Aromatase Activity ◽  
Histological Images ◽  
17Β Estradiol ◽  
Learning Software

AbstractMany teleost fishes undergo natural sex change, and elucidating the physiological and molecular controls of this process offers unique opportunities not only to develop methods of controlling sex in aquaculture settings, but to better understand vertebrate sexual development more broadly. Induction of sex change in some sequentially hermaphroditic or gonochoristic fish can be achieved in vivo through social manipulation, inhibition of aromatase activity, and steroid treatment. However, the induction of sex change in vitro has been largely unexplored. In this study, we established an in vitro culture system for ovarian explants in serum-free medium for a model sequential hermaphrodite, the New Zealand spotty wrasse (Notolabrus celidotus). This culture technique enabled evaluating the effect of various treatments with 17β-estradiol (E2), 11-ketotestosterone (11KT) or cortisol (CORT) on spotty wrasse ovarian architecture for 21 days. A quantitative approach to measuring the degree of ovarian atresia within histological images was also developed, using pixel-based machine learning software. Ovarian atresia likely due to culture was observed across all treatments including no-hormone controls, but was minimised with treatment of at least 10 ng/mL E2. Neither 11KT nor CORT administration induced proliferation of spermatogonia (i.e. sex change) in the cultured ovaries indicating culture beyond 21 days may be needed to induce sex change in vitro. The in vitro gonadal culture and analysis systems established here enable future studies investigating the paracrine role of sex steroids, glucocorticoids and a variety of other factors during gonadal sex change in fish.

CATECHOL OESTROGENS AND GONADOTROPHIN SECRETION IN THE EWE: AFFINITY FOR PITUITARY OESTROGEN RECEPTORS IN VITRO AND ACTION ON GONADOTROPHIN SECRETION IN VIVO

1980 ◽  
Vol 85 (3) ◽  
pp. 503-509 ◽  
Author(s):  
I. J. CLARKE ◽  
J. K. FINDLAY
Keyword(s):  
Negative Feedback ◽  
Oestrogen Receptor ◽  
Dose Response Relationship ◽  
Concurrent Administration ◽  
Feedback Effects ◽  
Dependent Relationship ◽  
Gonadotrophin Secretion ◽  
Dose Dependent

The binding of three catechol oestrogens, 2-OH-oestradiol-17β, 4-OH-oestrone and 2-OH-oestrone, to the ovine pituitary oestrogen receptor was measured in vitro to establish doses for the assessment of the effects of catechol oestrogens in vivo. Relative to oestradiol (100%) the compounds had receptor affinities of 30, 20 and 5% respectively. A dose of oestradiol sufficient to cause negative-feedback effects on the secretion of LH and FSH in ovariectomized ewes was established by intracarotid (i.c.) injections of 0·625–5·0 μg/dose (n = 3), and by measuring plasma levels of gonadotrophins in jugular venous samples taken at intervals of 20 min from 3 h before until 4 h after injection. A dose-dependent relationship (r = 0·88, P<0·001) was found for oestradiol and plasma LH levels. Plasma FSH was slightly (12–25%) but significantly (P<0·05) reduced by doses of 1·25–5·0 μg oestradiol, but no dose–response relationship was observed. Ovariectomized ewes (n = 4/group) were given 2·5 μg oestradiol (i.c.) simultaneously with 83 μg 2-OH-oestradiol, 125 μg 4-OH-oestrone or 500 μg 2-OH-oestrone. These doses of catechol oestrogens were chosen as being ten times that of oestradiol, with the relative affinities for oestrogen receptor taken into account. Concurrent administration of such doses of catechol oestrogens had no effect on the negative-feedback action of oestradiol in vivo. We have concluded that catechol oestrogens in the circulation probably do not modulate the action of oestradiol on release of LH or FSH; this does not preclude a possible role for them as locally produced regulators of oestrogen action.

Surface binding and uptake of polycationic ferritin by neonatal piglet intestinal epithelium

1980 ◽  
Vol 46 (1) ◽  
pp. 235-252
Author(s):  
C.C. Chase ◽  
E.A. Munn
Keyword(s):  
Specific Interaction ◽  
Age Groups ◽  
Similar Distribution ◽  
Surface Binding ◽  
Protein Uptake ◽  
In Vivo Experiments ◽  
Absorptive Cells ◽  
Apical Vesicles

Pieces of small intestine from newborn, I- and 6-day-old piglets were incubated in vitro and ligated segments were incubated in vivo with polycationic ferritin (PCF) to determine the distribution and possible role in protein uptake of anionic sites on membranes at the luminal surfaces of the epithelial cells. Most PCF binding to the absorptive cells occurred on the upper third or half of the villi and to some non-absorptive cells (tuft cells) throughout the length of the villi. Pieces of intestine which were fixed before incubation had PCF on microvilli and apical invaginations of absorptive cells, but none in the sub-apical tubules. When samples were incubated with PCF in vitro before fixation PCF was bound to the surfaces of microvilli of absorptive cells and to the membranes lining the apical invaginations, some sub-apical vesicles and some sub-apical tubules in all age-groups. In vivo experiments with longer incubation times resulted in a similar distribution, with increased amounts of PCF in the sub-apical tubules in samples from newborn and 1-day-old piglets only. In the newborn there were small vesicles containing PCF which had apparently moved further into the cells. At the same concentration (2 mg/ml) ferritin did not enter the sub-apical tubules; but it did enter and was taken up by the cells in the presence of 4% (w/v) serum albumin. It is concluded that the mechanism of protein uptake does not involve the microvillar membrane and that non-specific interaction with the invaginated plasma membrane, as a function of charge-density, leads to opening of the sub-apical tubular system to protein. Movement further into the cell depends on other factors.

Longitudinal force and stress of rat's esophagus: age-related changes.

1977 ◽  
Vol 232 (6) ◽  
pp. E580
Author(s):  
M P Zabinski ◽  
P Biancani
Keyword(s):  
Age Groups ◽  
Longitudinal Direction ◽  
Longitudinal Force ◽  
Active Stress ◽  
Length Relationship ◽  
Age Related ◽  
Old Rats ◽  
The Difference

Longitudinal force-length relationship of the rat esophagus was studied in vitro in three age groups: 1 mo, 3 mo, and 12 mo. The length of maximum force development (MFD) occurs at 1.4-1.5 times the in vivo length for all age groups. The active force developed at MFD increases markedly with age. The difference in the active forces in the 3-mo and 12-mo age groups is due to differences in cross section because the active stress of the esophagus in the longitudinal direction is approximately equal for the two age groups. The active stress in the 1-mo-old rats is lower than in the 3-mo-old rats, suggesting an increased contractility of the esophagus with age in this period of development.

Trophic Effect of Porcine Sertoli Cells on Rat and Human Ventral Mesencephalic Cells and Hnt Neurons in Vitro

1998 ◽  
Vol 7 (2) ◽  
pp. 157-164 ◽  
Author(s):  
Agneta I. Othberg ◽  
Alison E. Willing ◽  
Don F. Cameron ◽  
Alex Anton ◽  
Samuel Saporta ◽  
...  
Keyword(s):  
Sertoli Cells ◽  
Islet Cells ◽  
Treated Group ◽  
Term Survival ◽  
Teratocarcinoma Cell ◽  
Trophic Effect ◽  
Soma Size ◽  
Ventral Mesencephalic

The poor survival of embryonic dopaminergic (DA) neurons transplanted into patients with Parkinson's disease (PD) has encouraged researchers to search for new methods to affect the short- as well as long-term survival of these neurons after transplantation. In several previous rodent studies Sertoli cells increased survival of islet cells and chromaffin cells when cotransplanted in vivo. The aims of this study were to investigate whether porcine Sertoli cells had a positive effect on the survival and maturation of rat and human DA neurons, and whether the Sertoli cells had an effect on differentiation of neurons derived from a human teratocarcinoma cell line (hNT neurons). A significant increase of tyrosine hydroxylase (TH)-positive neurons of both rat and human ventral mesencephalic tissue was found when cocultured with Sertoli cells. Furthermore, there was a significantly increased soma size and neurite outgrowth of neurons in the coculture treated group. The Sertoli cell and hNT coculture also revealed an increased number of TH-positive cells. These results demonstrate that the wide variety of proteins and factors secreted by porcine Sertoli cells benefit the survival and maturation of embryonic DA neurons and suggest that cotransplantation of Sertoli cells and embryonic DA neurons may be useful for a cell transplantation therapy in PD.

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