scholarly journals Reduced Intratesticular Testosterone Concentration Alters the Polymerization State of the Sertoli Cell Intermediate Filament Cytoskeleton by Degradation of Vimentin

Endocrinology ◽  
2003 ◽  
Vol 144 (12) ◽  
pp. 5530-5536 ◽  
Author(s):  
Matthew D. Show ◽  
Matthew D. Anway ◽  
Janet S. Folmer ◽  
Barry R. Zirkin

Abstract The Sertoli cell intermediate filament cytoskeleton is composed of the type III family member vimentin. The distribution of Sertoli cell vimentin varies with the stage of spermatogenesis, with shortening of the filaments at stages VII–VIII, the stages of spermiation. Experimental reduction in intratesticular testosterone (T) concentration also results in the sloughing of advanced spermatids from the Sertoli cells, as well as in the apoptotic death of spermatocytes. We hypothesized that alteration of the distribution of Sertoli cell vimentin might play a role in the loss of germ cells that occurs in response to reduced intratesticular T. To test this hypothesis, intratesticular T was reduced by implanting LH-suppressive SILASTIC brand capsules containing T and estradiol into adult rats for 8 wk. Immunohistochemical analyses revealed that, in response to the implants, the vimentin cytoskeleton collapsed around the Sertoli cell nuclei at all stages of the cycle, losing the extensive branching and structure normally seen at most stages of the cycle. Western blots of isolated Sertoli cells revealed that protein levels did not differ significantly between control and T- and estradiol-treated rats. However, Sertoli cell fractions containing the vimentin monomer revealed that vimentin was cleaved into four to five fragments in Sertoli cells in response to the implants, suggestive of proteolysis. These results indicate that, in response to reduced intratesticular T, the vimentin cytoskeleton of the Sertoli cell collapses to a perinuclear localization, and suggest that this collapse is associated with, and perhaps caused by, the degradation of the vimentin monomer rather than by loss of its expression.

2007 ◽  
Vol 292 (2) ◽  
pp. E513-E522 ◽  
Author(s):  
Andrii Domanskyi ◽  
Fu-Ping Zhang ◽  
Mirja Nurmio ◽  
Jorma J. Palvimo ◽  
Jorma Toppari ◽  
...  

Androgen receptor-interacting protein 4 (ARIP4) belongs to the SNF2 family of proteins involved in chromatin remodeling, DNA excision repair, and homologous recombination. It is a DNA-dependent ATPase, binds to DNA and mononucleosomes, and interacts with androgen receptor (AR) and modulates AR-dependent transactivation. We have examined in this study the expression and cellular localization of ARIP4 during postnatal development of mouse testis. ARIP4 was detected by immunohistochemistry in Sertoli cell nuclei at all ages studied, starting on day 5, and exhibited the highest expression level in adult mice. At the onset of spermatogenesis, ARIP4 expression became evident in spermatogonia, pachytene, and diplotene spermatocytes. Immunoreactive ARIP4 antigen was present in Leydig cell nuclei. In Sertoli cells ARIP4 was expressed in a stage-dependent manner, with high expression levels at stages II–VI and VII–VIII. ARIP4 expression patterns did not differ significantly in testes of wild-type, follicle-stimulating hormone receptor knockout, and luteinizing hormone receptor knockout mice. In testes of hypogonadal mice, ARIP4 was found mainly in interstitial cells and exhibited lower expression in Sertoli and germ cells. In vitro stimulation of rat seminiferous tubule segments with testosterone, FSH, or forskolin did not significantly change stage-specific levels of ARIP4 mRNA. Heterozygous ARIP4+/− mice were haploinsufficient and had reduced levels of Sertoli-cell specific androgen-regulated Rhox5 (also called Pem) mRNA. Collectively, ARIP4 is an AR coregulator in Sertoli cells in vivo, but the expression in the germ cells implies that it has also AR-independent functions in spermatogenesis.


1988 ◽  
Vol 118 (3) ◽  
pp. R13-R16 ◽  
Author(s):  
B. LE MAGUERESSE ◽  
C. PINEAU ◽  
F. GUILLOU ◽  
B. JEGOU

ABSTRACT Indirect approach (hypotonic treatment) and direct approaches (co-cultures and conditioned media) were used in order to investigate the effects of germ cells from adult rats upon transferrin secretion by Sertoli cell cultures prepared from 20-day-old rats. Removal of germ cells contaminating the Sertoli cell cultures resulted in a significant decrease in transferrin secretion whereas the addition of crude germ cell preparations or of enriched preparations of pachytene spermatocytes, early spermatids and of liver epithelial cells (LEC) markedly stimulated this parameter. Furthermore, spent media of pachytene spermatocytes and of early spermatids, but not of LEC, also stimulated transferrin production. It is concluded that germ cells normally located within the adluminal compartment of the seminiferous tubules may be capable of controlling their own supply of iron via their influence upon transferrin secretion by the Sertoli cells.


Author(s):  
Rita Meyer ◽  
Zoltan Posalaky ◽  
Dennis Mcginley

The Sertoli cell tight junctional complexes have been shown to be the most important structural counterpart of the physiological blood-testis barrier. In freeze etch replicas they consist of extensive rows of intramembranous particles which are not only oriented parallel to one another, but to the myoid layer as well. Thus the occluding complex has both an internal and an overall orientation. However, this overall orientation to the myoid layer does not seem to be necessary to its barrier function. The 20 day old rat has extensive parallel tight junctions which are not oriented with respect to the myoid layer, and yet they are inpenetrable by lanthanum. The mechanism(s) for the control of Sertoli cell junction development and orientation has not been established, although such factors as the presence or absence of germ cells, and/or hormones, especially FSH have been implicated.


Endocrinology ◽  
2005 ◽  
Vol 146 (3) ◽  
pp. 1532-1540 ◽  
Author(s):  
Anne Florin ◽  
Magali Maire ◽  
Aline Bozec ◽  
Ali Hellani ◽  
Sonia Chater ◽  
...  

In the present study we investigated whether fetal exposure to flutamide affected messenger and protein levels of claudin-11, a key Sertoli cell factor in the establishment of the hemotesticular barrier, at the time of two key events of postnatal testis development: 1) before puberty (postnatal d 14) during the establishment of the hemotesticular barrier, and 2) at the adult age (postnatal d 90) at the time of full spermatogenesis. The data obtained show that claudin-11 expression was inhibited in prepubertal rat testes exposed in utero to 2 and 10 mg/kg·d flutamide. However, in adult testes, the inhibition was observed only with 2, and not with 10, mg/kg·d of the antiandrogen. It is shown here that these differences between prepubertal and adult testes could be related to dual and opposed regulation of claudin-11 expression resulting from positive control by androgens and an inhibitory effect of postmeiotic germ cells. Indeed, testosterone is shown to stimulate claudin-11 expression in cultured Sertoli cells in a dose- and time-dependent manner (maximum effect with 0.06 μm after 72 h of treatment). In contrast, postmeiotic germ cells potentially exert a negative effect on claudin-11 expression, because adult rat testes depleted in spermatids (after local irradiation) displayed increased claudin-11 expression, whereas in a model of cocultured Sertoli and germ cells, spermatids, but not spermatocytes, inhibited claudin-11 expression. The apparent absence of claudin-11 expression changes in adult rat testes exposed to 10 mg/kg·d flutamide therefore could result from the antagonistic effects of 1) the inhibitory action of the antiandrogen and 2) the stimulatory effect of the apoptotic germ cells on claudin-11 expression. Together, due to the key role of claudin-11 in the hemotesticular barrier, the present findings suggest that such regulatory mechanisms may potentially affect this barrier (re)modeling during spermatogenesis.


Development ◽  
1994 ◽  
Vol 120 (7) ◽  
pp. 1759-1766 ◽  
Author(s):  
K. Yomogida ◽  
H. Ohtani ◽  
H. Harigae ◽  
E. Ito ◽  
Y. Nishimune ◽  
...  

GATA-1 is an essential factor for the transcriptional activation of erythroid-specific genes, and is also abundantly expressed in a discrete subset of cells bordering the seminiferous epithelium in tubules of the murine testis. In examining normal and germ-line defective mutant mice, we show here that GATA-1 is expressed only in the Sertoli cell lineage in mouse testis. GATA-1 expression in Sertoli cells is induced concomitantly with the first wave of spermatogenesis, and GATA-1-positive cells are uniformly distributed among all tubules during prepubertal testis development. However, the number of GATA-1-positive cells declines thereafter and were found only in the peripheral zone of seminiferous tubules in stages VII, VIII and IX of spermatogenesis in the adult mouse testis. In contrast, virtually every Sertoli cell in mutant W/Wv, jsd/jsd or cryptorchid mice (all of which lack significant numbers of germ cells) expresses GATA-1, thus showing that the expression of this transcription factor is negatively controlled by the maturing germ cells. These observations suggest that transcription factor GATA-1 is a developmental stage- and spermatogenic cycle-specific regulator of gene expression in Sertoli cells.


2008 ◽  
Vol 20 (9) ◽  
pp. 36
Author(s):  
S. M. Ruwanpura ◽  
P. G. Stanton ◽  
D. M. Robertson ◽  
R. I. McLachlan ◽  
Y. Makanji ◽  
...  

Follicle stimulating hormone (FSH) in short-term rat studies supports spermatogenesis at multiple levels, notably spermatogonial development. The role of FSH in supporting full spermatogenesis in rats is still in question as long-term studies have not been possible due the development of neutralising antibodies to heterologous FSH preparations. This study sought to assess the effects of a homologous recombinant rat FSH (rr-FSH) preparation on the long-term restoration of spermatogenesis. Adult rats were GnRH-immunised (GnRH-im) for 12 weeks then, administered an anti-androgen; flutamide (flut), alone or together with rr-FSH (8µg/rat/daily) for 56 days (1 spermatogenic cycle). Germ and Sertoli cell numbers were quantified using an optical disector stereological method. Testis weight, serum FSH and inhibin B and Sertoli cell nuclear volume were significantly reduced to 15%, 13%, 25% and 57% of controls respectively, following GnRH-im+flut treatment. GnRH-im+flut treatment reduced A/I spermatogonial, type B spermatogonial+preleptotene, leptotene+zygotene and early pachytene spermatocyte numbers to 28%, 68%, 50% and 19% (P < 0.001) of controls respectively, with later germ cells rarely observed. After FSH treatment, no significant affect on testis weight, serum FSH and inhibin B or Sertoli cell number were observed. However, rr-FSH treatment significantly increased numbers of A/I spermatogonia, leptotene+zygotene and early pachytene spermatocytes from 28 = >42%, 50 = >69% and 19 = >27% of controls, respectively, while no differences were observed in later germ cell types. rr-FSH also increased (P < 0.05) the volume of Sertoli cell nuclei from 57 = >66% of control. In conclusion, FSH is unable to support full rat spermatogenesis; however, FSH can partially support germ cells notably spermatogonia through to early pachytene spermatocytes, despite the absence of androgenic support.


1990 ◽  
Vol 2 (3) ◽  
pp. 225 ◽  
Author(s):  
Kretser DM de

The interactions between the Sertoli cells and germ cells are progressively becoming an important part of testicular physiology. This paper explores the cytological basis for these interactions, detailing the cyclic changes in the Sertoli cells in concert with the stages of the seminiferous cycle and the nature of the blood-testis barrier. These cytological changes are correlated with a number of variations in the function of Sertoli cells. The mechanisms by which germ cells and Sertoli cells interact are explored and can be divided into those using cell-to-cell contact and others utilizing paracrine factors.


Reproduction ◽  
2016 ◽  
Vol 152 (2) ◽  
pp. R31-R40 ◽  
Author(s):  
Hong Wang ◽  
Liping Wen ◽  
Qingqing Yuan ◽  
Min Sun ◽  
Minghui Niu ◽  
...  

Within the seminiferous tubules there are two major cell types, namely male germ cells and Sertoli cells. Recent studies have demonstrated that male germ cells and Sertoli cells can have significant applications in treating male infertility and other diseases. However, primary male germ cells are hard to proliferatein vitroand the number of spermatogonial stem cells is scarce. Therefore, methods that promote the expansion of these cell populations are essential for their use from the bench to the bed side. Notably, a number of cell lines for rodent spermatogonia, spermatocytes and Sertoli cells have been developed, and significantly we have successfully established a human spermatogonial stem cell line with an unlimited proliferation potential and no tumor formation. This newly developed cell line could provide an abundant source of cells for uncovering molecular mechanisms underlying human spermatogenesis and for their utilization in the field of reproductive and regenerative medicine. In this review, we discuss the methods for establishing spermatogonial, spermatocyte and Sertoli cell lines using various kinds of approaches, including spontaneity, transgenic animals with oncogenes, simian virus 40 (SV40) large T antigen, the gene coding for a temperature-sensitive mutant ofp53, telomerase reverse gene (Tert), and the specific promoter-based selection strategy. We further highlight the essential applications of these cell lines in basic research and translation medicine.


2004 ◽  
Vol 183 (1) ◽  
pp. 79-90 ◽  
Author(s):  
A Bozec ◽  
F Chuzel ◽  
S Chater ◽  
C Paulin ◽  
R Bars ◽  
...  

In utero exposure to exogenous anti-androgenic compounds induces a wide range of abnormalities of the reproductive system, including hypospermatogenesis, cryptorchidism and hypospadias. By using rats exposed in utero to the anti-androgenic compound flutamide (0.4, 2 or 10 mg/kg per day), it has been shown that hypospermatogenesis in adult testes could be related to (i) a long-term apoptosis in germ cells but not in somatic Leydig and Sertoli cells as evidenced by the TUNEL approach and (ii) alterations in the mRNA and protein expression of pro- (Bax, Bak, Bid) and anti-apoptotic (Bcl-2, Bcl-w) members of the Bcl-2 family. Indeed, the number of apoptotic germ cells increased with the dose of flutamide administered and the apoptotic germ cells were mainly detected at androgen-dependent stages VII–VIII. Moreover, for the Bcl-2-related proteins that were expressed mainly in the germ cells, a decrease in the levels of anti-apoptotic peptides Bcl-w (60%, P=0.003) and Bcl-2 (90%, P=0.0001) was observed at 2 mg/kg per day flutamide and an increase in levels of the pro-apoptotic Bax (2.3-fold, P=0.0004) was detected at 10 mg/kg per day. In contrast, the levels of pro-apoptotic peptide Bak that was mainly expressed in somatic cells decreased (70%, P=0.0008) at 10 mg/kg per day. Such alterations in Bcl-2-related peptides occurred mainly at the protein level except for Bcl-2 (72%, P=0.0001) and Bak (43%, P=00002) transcripts. Together, these results showed that the apoptosis observed in adult germ cells from rats exposed in utero to flutamide may result from a long-term alteration in the balance between pro- and anti-apoptotic Bcl-2-related molecules in favour of pro-apoptotic proteins. These data further supported the concept of an androgen-dependent fetal programming that is in relation with an alteration of the expression of Bcl-2-related genes/proteins promoting apoptosis in testicular germ cells of adult rats with fetal androgen disruption.


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