BLOOD–TESTIS BARRIER: EVIDENCE FOR INTACT INTER-SERTOLI CELL JUNCTIONS AFTER HYPOPHYSECTOMY IN THE ADULT RAT

1978 ◽  
Vol 76 (1) ◽  
pp. 87-91 ◽  
Author(s):  
L. HAGENÄS ◽  
L. PLÖEN ◽  
H. EKWALL
Keyword(s):  
Sertoli Cell ◽  
Structural Integrity ◽  
Cell Junctions ◽  
Junctional Complex ◽  
Tracer Technique ◽  
Adult Rats ◽  
Adult Rat ◽  
Hormonal Dependence ◽  
Lanthanum Tracer ◽  
Blood Testis Barrier

SUMMARY To study the hormonal dependence of the blood–testis barrier, adult rats were hypophysectomized and the ultrastructural integrity of the inter-Sertoli cell junctional complex was examined at various times with a lanthanum tracer technique. It was found that the structural integrity of the inter-Sertoli cell junctions and their capacity to exclude lanthanum from the adluminal compartment were preserved up to 35 days after hypophysectomy. Furthermore, transport of newly formed spermatocytes through the inter-Sertoli cell junctions still occurred 20 days after hypophysectomy. It is therefore concluded that the function of the inter-Sertoli cell junctional complex is not directly dependent on gonadotrophic or androgenic hormones, but is regulated by other mechanisms.

scholarly journals FSH regulates the formation of adherens junctions and ectoplasmic specialisations between rat Sertoli cells in vitro and in vivo

2006 ◽  
Vol 189 (2) ◽  
pp. 381-395 ◽  
Author(s):  
P Sluka ◽  
L O’Donnell ◽  
J R Bartles ◽  
P G Stanton
Keyword(s):  
Sertoli Cell ◽  
Sertoli Cells ◽  
Adherens Junctions ◽  
Adherens Junction ◽  
Cell Junctions ◽  
Junctional Complex ◽  
Intermediate Filament Protein ◽  
Adult Rat

Spermatogenesis is dependent on the ability of Sertoli cells to form mature junctions that maintain a unique environment within the seminiferous epithelium. Adjacent Sertoli cells form a junctional complex that includes classical adherens junctions and testis-specific ectoplasmic specialisations (ES). The regulation of inter-Sertoli cell junctions by the two main endocrine regulators of spermatogenesis, FSH and testosterone, is unclear. This study aimed to investigate the effects of FSH and testosterone on inter-Sertoli cell adherens junctions (as determined by immunolocalisation of cadherin, catenin and actin) and ES junctions (as determined by immunolocalisation of espin, actin and vinculin) in cultured immature Sertoli cells and GnRH-immunised adult rat testes given FSH or testosterone replacement in vivo. When hormones were absent in vitro, adherens junctions formed as discrete puncta between interdigitating, finger-like projections of Sertoli cells, but ES junctions were not present. The adherens junction puncta included actin filaments that were oriented perpendicularly to the Sertoli cell plasma membrane, but were not associated with the intermediate filament protein vimentin. When FSH was added in vitro, ES junctions formed, and adjacent adherens junction puncta fused into extensive adherens junction belts. After hormone suppression in vivo, ES junctions were absent, while FSH replacement restored ES junctions, as confirmed by electron microscopy and confocal analysis of ES-associated proteins. Testosterone alone did not affect adherens junctions or ES in vitro or in vivo. We conclude that FSH can regulate the formation of ES junctions and stimulate the organisation and orientation of extensive adherens junctions in Sertoli cells.

Adult rat Sertoli cells secrete a factor or factors which modulate Leydig cell function

1987 ◽  
Vol 114 (3) ◽  
pp. 459-467 ◽  
Author(s):  
V. Papadopoulos ◽  
P. Kamtchouing ◽  
M. A. Drosdowsky ◽  
M. T. Hochereau de Reviers ◽  
S. Carreau
Keyword(s):  
Cyclic Amp ◽  
Sertoli Cell ◽  
Leydig Cell ◽  
Sertoli Cells ◽  
Leydig Cells ◽  
Cell Function ◽  
Cell Interaction ◽  
Adult Rats ◽  
Adult Rat ◽  
Stimulating Factor

ABSTRACT Production of testosterone and oestradiol-17β by Leydig cells from adult rats was stimulated by LH or dibutyryl cyclic AMP (10 and 2·5-fold respectively). The addition of spent medium from normal, hemicastrated or γ-irradiated rat seminiferous tubule cultures, as well as from Sertoli cell cultures, to purified Leydig cells further enhanced both basal (44 and 53% for testosterone and oestradiol-17β respectively) and LH-stimulated (56 and 18%) steroid output. Simultaneously, a decrease (20–30%) in intracellular cyclic AMP levels was observed. This stimulating factor (or factors) secreted by the Sertoli cells is different from LHRH, is of proteinic nature and has a molecular weight ranging between 10 000 and 50 000; its synthesis is not controlled by FSH nor by testosterone. This factor(s) involved in rat Leydig cell steroidogenesis, at a step beyond the adenylate cyclase, does not require protein synthesis for testosterone formation whereas it does for oestradiol-17β production. It should be noted that a germ cell–Sertoli cell interaction modulates the synthesis of this factor(s). J. Endocr. (1987) 114, 459–467

Lonidamine-ethyl ester-mediated remodelling of the Sertoli cell cytoskeleton induces phosphorylation of plakoglobin and promotes its interaction with α-catenin at the blood–testis barrier

2017 ◽  
Vol 29 (5) ◽  
pp. 998 ◽  
Author(s):  
Dolores D. Mruk ◽  
Michele Bonanomi ◽  
Bruno Silvestrini
Keyword(s):  
Ethyl Ester ◽  
Sertoli Cell ◽  
Germ Cells ◽  
Fluorescent Microscopy ◽  
Adherens Junction ◽  
Cell Junctions ◽  
Hormonal Contraceptives ◽  
Tubule Lumen ◽  
Human Use ◽  
Blood Testis Barrier

Several compounds affect male fertility by disrupting the adhesion of germ cells to Sertoli cells, which results in the release of undeveloped germ cells into the seminiferous tubule lumen that are incapable of fertilising the ovum. Indazole carboxylic acids are one class of compounds exhibiting such effects and they have been investigated as non-hormonal contraceptives for potential human use. The aims of this study were to investigate the effects of lonidamine-ethyl ester, an indazole carboxylic acid, on spermatogenesis and cell junctions, in particular, desmosomes. We found two doses of lonidamine-ethyl ester at 50 mg kg–1 to disrupt Sertoli–germ cell adhesion. By light and fluorescent microscopy, pronounced changes were observed in the distribution of actin microfilaments and intermediate filaments, as well as in the localisation of plakoglobin, a protein with structural and signalling roles at the desmosome and adherens junction at the blood–testis barrier. Furthermore, immunoblotting and immunoprecipitation experiments using testis lysates revealed a significant upregulation (P < 0.01) of plakoglobin and Tyr-phosphorylated plakoglobin. Co-immunoprecipitation experiments showed an increase in the interaction between plakoglobin and fyn proto-oncogene, an Src family non-receptor tyrosine kinase, after treatment, as well as an increase in the interaction between plakoglobin and α-catenin. Taken collectively, these data indicate that a disruption of Sertoli cell and spermatocyte–spermatid adhesion in the seminiferous epithelium by lonidamine-ethyl ester results in the phosphorylation of plakoglobin, thereby promoting its interaction with α-catenin at the blood–testis barrier.

scholarly journals UXT in Sertoli cells is required for blood–testis barrier integrity†

2020 ◽  
Vol 103 (4) ◽  
pp. 880-891
Author(s):  
Phillip A Thomas ◽  
Eric D Schafler ◽  
Sophie E Ruff ◽  
Maud Voisin ◽  
Susan Ha ◽  
...  
Keyword(s):  
Sertoli Cell ◽  
Germ Cells ◽  
Sertoli Cells ◽  
Structural Integrity ◽  
Cell Function ◽  
Somatic Tissue ◽  
Seminiferous Tubules ◽  
Testis Size ◽  
Conditional Deletion ◽  
Blood Testis Barrier

Abstract Spermatogenesis is a complex process that establishes male fertility and involves proper communication between the germline (spermatozoa) and the somatic tissue (Sertoli cells). Many factors that are important for spermatozoa production are also required for Sertoli cell function. Recently, we showed that the transcriptional cofactor ubiquitously expressed transcript (UXT) encodes a protein that is essential in germ cells for spermatogenesis and fertility. However, the role of UXT within Sertoli cells and how it affects Sertoli cell function was still unclear. Here we describe a novel role for UXT in the Sertoli cell’s ability to support spermatogenesis. We find that the conditional deletion of Uxt in Sertoli cells results in smaller testis size and weight, which coincided with a loss of germ cells in a subset of seminiferous tubules. In addition, the deletion of Uxt has no impact on Sertoli cell abundance or maturity, as they express markers of mature Sertoli cells. Gene expression analysis reveals that the deletion of Uxt in Sertoli cells reduces the transcription of genes involved in the tight junctions of the blood–testis barrier (BTB). Furthermore, tracer experiments and electron microscopy reveal that the BTB is permeable in UXT KO animals. These findings broaden our understanding of UXT’s role in Sertoli cells and its contribution to the structural integrity of the BTB.

scholarly journals Cell polarity, cell adhesion, and spermatogenesis: role of cytoskeletons

F1000Research ◽  
2017 ◽  
Vol 6 ◽  
pp. 1565 ◽  
Author(s):  
Linxi Li ◽  
Ying Gao ◽  
Haiqi Chen ◽  
Tito Jesus ◽  
Elizabeth Tang ◽  
...  
Keyword(s):  
Cell Adhesion ◽  
Cell Polarity ◽  
Sertoli Cell ◽  
Connexin 43 ◽  
Planar Cell Polarity ◽  
Protein Complexes ◽  
Seminiferous Epithelium ◽  
Cell Junctions ◽  
Adhesion Protein ◽  
Adult Rat

In the rat testis, studies have shown that cell polarity, in particular spermatid polarity, to support spermatogenesis is conferred by the coordinated efforts of the Par-, Crumbs-, and Scribble-based polarity complexes in the seminiferous epithelium. Furthermore, planar cell polarity (PCP) is conferred by PCP proteins such as Van Gogh-like 2 (Vangl2) in the testis. On the other hand, cell junctions at the Sertoli cell–spermatid (steps 8–19) interface are exclusively supported by adhesion protein complexes (for example, α6β1-integrin-laminin-α3,β3,γ3 and nectin-3-afadin) at the actin-rich apical ectoplasmic specialization (ES) since the apical ES is the only anchoring device in step 8–19 spermatids. For cell junctions at the Sertoli cell–cell interface, they are supported by adhesion complexes at the actin-based basal ES (for example, N-cadherin-β-catenin and nectin-2-afadin), tight junction (occludin-ZO-1 and claudin 11-ZO-1), and gap junction (connexin 43-plakophilin-2) and also intermediate filament-based desmosome (for example, desmoglein-2-desmocollin-2). In short, the testis-specific actin-rich anchoring device known as ES is crucial to support spermatid and Sertoli cell adhesion. Accumulating evidence has shown that the Par-, Crumbs-, and Scribble-based polarity complexes and the PCP Vangl2 are working in concert with actin- or microtubule-based cytoskeletons (or both) and these polarity (or PCP) protein complexes exert their effects through changes in the organization of the cytoskeletal elements across the seminiferous epithelium of adult rat testes. As such, there is an intimate relationship between cell polarity, cell adhesion, and cytoskeletal function in the testis. Herein, we critically evaluate these recent findings based on studies on different animal models. We also suggest some crucial future studies to be performed.

Degradation of IGF-I in the adult rat gastrointestinal tract is limited by a specific antiserum or the dietary protein casein

1995 ◽  
Vol 146 (2) ◽  
pp. 215-225 ◽  
Author(s):  
C J Xian ◽  
C A Shoubridge ◽  
L C Read
Keyword(s):  
Receptor Binding ◽  
Dietary Protein ◽  
Half Life ◽  
Structural Integrity ◽  
Binding Activity ◽  
Adult Rats ◽  
Adult Rat ◽  
Igf I

Abstract To investigate the potential of IGF-I peptides as therapeutics in the gut, the survival profiles of a bolus of 125I-labelled IGF-I (8·6 ng) in vivo in various ligated gut segments of fasted adult rats have been examined. The intactness of IGF-I tracer in the flushed luminal contents was estimated by trichloroacetic acid precipitation, antibody and receptor binding assays. It was found that IGF-I was degraded very rapidly in duodenum and ileum segments with a half-life (t1/2) of 2 min by all three methods. IGF-I was slightly more stable in the stomach (t1/2=8, 5 and 2·5 min by the above three methods), and considerably more stable in the colon (t1/2=38, 33 and 16 min as judged by the three methods). Rates of degradation in gut flushings in vitro were similar to the in vivo rates except for the colon, where IGF-I was proteolysed more rapidly in vivo. As a means of developing gut-stable and active forms of IGF-I, several approaches were examined for their effectiveness in prolonging IGF-I survival in the upper gut. It was found that the extension peptide on the analogue, LR3IGF-I did not protect IGF-I, nor did association with IGF-binding protein-3. However, an IGF-I antiserum was effective in prolonging IGF-I half-life in duodenum fluid by 28-fold. Charge interaction between IGF-I and heparin could also protect IGF-I in the stomach but not in duodenum flushings. Furthermore, casein (a non-specific dietary protein) and to a lesser extent, BSA and lactoferrin, were effective in preserving IGF-I structural integrity and receptor binding activity in both stomach and duodenum fluids. It can be concluded that IGF-I cannot be expected to retain bioactivity if delivered orally because of rapid proteolysis in the upper gut, but the use of IGF antibodies and casein could represent useful approaches for IGF-I protection in oral formulae. Journal of Endocrinology (1995) 146, 215–225

scholarly journals HOMOLOGOUS DISEASE IN THE ADULT RAT, A MODEL FOR AUTOIMMUNE DISEASE

1963 ◽  
Vol 118 (4) ◽  
pp. 635-648 ◽  
Author(s):  
Peter Stastny ◽  
Vernie A. Stembridge ◽  
Morris Ziff
Keyword(s):  
Autoimmune Disease ◽  
Lupus Erythematosus ◽  
Connective Tissue Diseases ◽  
Skin Lesions ◽  
Cutaneous Lesions ◽  
Adult Rats ◽  
Hydropic Degeneration ◽  
Skin Changes ◽  
Adult Rat ◽  
The One

The cutaneous lesions of adult rats with homologous disease are described, and evidence is presented to indicate that they have an immunologic basis. The skin changes included erythema, purpura, edema, and a variety of inflammatory lesions. In the more active lesions, dermal infiltration, hydropic degeneration, acanthosis, and atrophy of the epidermis with hyperkeratosis and follicular plugging were present. In some cases, ulceration and sloughing were also observed. More chronic lesions were characterized by atrophy of the epidermis and collagenization of the dermis with disappearance of the skin appendages. Rejection of autografts was observed simultaneously with acceptance of homografts. The histologic appearance of autografts undergoing rejection was similar to that of the spontaneous skin lesions, suggesting that the latter, too, had an immunologic basis. In favor of this, also, was the specificity of the dermatitis for the skin of the host, with sparing of neighboring homograft tissue. There was a histologic similarity between the spontaneous skin lesions of homologous disease and those of lupus erythematosus on the one hand, and scleroderma on the other, thus supporting the possibility that the cutaneous lesions of these connective tissue diseases of man may also have an immunologic basis. It was concluded that the adult rat with homologous disease may furnish a model for human autoimmune disease.

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