Changes of sertoli cell glycoproteins induced by removal of the associated germ cells (original) (raw)
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Effects of serum components on the morphology of sertoli cells in culture
The Anatomical Record, 1980
Studies of Sertoli cell structure, maturation, and function have been aided by the use of in vitro systems. Although numerous papers have appeared that utilize the Sertoli cell culture model, few papers have dealt with the characterization of these cells under various culture environments. Recently, i t has been reported that the addition of serum to the culture medium prevents induction of long cytoplasmic appendages in cultured Sertoli cells that have been treated with FSH, TSH, or cAMP. The purpose of this investigation was to determine which serum components, obtained by gel filtration, are capable of inhibiting the morphological response induced by FSH, TSH, or cAMP. Sertoli cell-enriched cultures were prepared using collagenase and trypsin digestion, each followed by gravity sedimentation. Untreated cells grown on plastic or glass substrates assumed a n epithelioid appearance after several days. Cells treated with FSH, TSH, or cAMP formed long cytoplasmic appendages after 1-2 days. This response was prevented or reversed by the addition of fetal calf serum (lo%), crystallized bovine serum albumin (0.25%-2%), or purified albumin obtained by gel filtration of whole serum (0.25%). I t was also found that fractions t h a t elute between the void volume and the initial albumin fractions (molecular weights of approximately 50,000 and greater) mimic the hormone-induced response after only 1 G 1 2 hours. The results of this investigation indicate that albumin is the primary serum component responsible for inhibiting morphological alterations induced by FSH, TSH, and cAMP. Furthermore, i t is apparent t h a t the production of long filamentous cytoplasmic appendages in Sertoli cells can be induced by a wide variety of substances.
The second messenger pathway for germ cell-mediated stimulation of Sertoli cells
Biochemical and Biophysical Research Communications, 1992
Treatment of cultured rat Sertoli cells with FSH or dibutyryl CAMP for 30 min resulted in phosphorylation of the same Sertoli cell proteins. Different Sertoli cell proteins were phosphorylated after calcium ionophore A23187 and 12-0-tetradecanoylphorbol-13acetate (TPA) treatment. A23187 stimulated the phosphorylation of hsp27, while TPA alone had no effect. TPA plus A23187 resulted in phosphorylation of a 14 kDa protein, in addition to hsp27. The effect of TPA plus A23187 was identical to that of germ cells on Sertoli cell protein phosphorylation. FSH-stimulated CAMP production by Sertoli cells was reduced by prior exposure of Sertoli cells to germ cells. The results indicate that germ cells stimulate Sertoli cells by the inositol trisphosphate/diacylglycerol mediated second messenger pathway. The results also suggest that the germ cell-activated pathway interacts within Sertoli cells to modulate Sertoli cell response to FSH.
Morphological characteristics of male germ cells of rats in contact with Sertoli cells in vitro
Reproduction, 1979
Fragments of seminiferous epithelium were prepared from 3-week-old rats. Although the Sertoli cells formed a monolayer, germ cells (spermatogonia and early spermatocytes) remained in association with them and were of normal ultrastructural appearance. Germ cells became completely separated from Sertoli cells after 3 weeks of culture in a chemically defined medium. The contact areas between Sertoli and germ cells were characterized by desmosome-like junctions while those between germ cells appeared to be pentalaminar.
Germ Cells Regulate 3-Hydroxybutyrate Production In Rat Sertoli Cells
General and comparative endocrinology, 2017
Paracrine regulation of Sertoli cell function by germ cells is an outstanding characteristic of testicular physiology. It has been demonstrated that Sertoli cells produce ketone bodies and that germ cells may use them as energy source. The aim of the study was to analyze a possible regulation by germ cells of ketogenesis in Sertoli cells. Cultures of Sertoli cells (SC) obtained from 31-day-old rats were co-cultured with germ cells (GC). The results presented herein show that the presence of GC stimulated 3-hydroxybutyrate production and increased mRNA levels of two enzymes involved in ketogenesis -carnitine palmitoyltransferase 1a (CPT1a) and mitochondrial 3-hydroxy-3-methylglutaryl-CoA (mHMGCoA) synthase- in SC. Additionally, GC increased monocarboxylate transporter 4 (Mct4) expression in SC, a transporter involved in ketone bodies exit. To evaluate if the observed effects might be mediated by soluble factors, SC cultures were incubated with germinal cell-conditioned medium (GCCM) ...
Regulation of 2-Macroglobulin Expression in Rat Sertoli Cells and Hepatocytes by Germ Cells In Vitro
Biology of Reproduction, 1998
␣ 2 -MG expression dose-dependently. These results illustrate that germ cells play a role in regulating testicular ␣ 2 -MG expression. Since Sertoli cells synthesize and secrete many of the serum proteins behind the blood-testis barrier that are also produced by hepatocytes, we sought to ascertain whether germ cells can affect hepatic ␣ 2 -MG expression. When germ cells were cocultured with hepatocytes isolated from adult rats, the hepatocyte ␣ 2 -MG steady-state mRNA level was shown to be stimulated by germ cells dose-dependently. Using different pools of fractions derived from GCCM after their fractionation by a preparative anion-exchange HPLC column, GCCM was found to contain a factor(s) that stimulated hepatocyte ␣ 2 -MG expression dose-dependently. More importantly, the fractions that stimulated hepatocyte ␣ 2 -MG expression had a retention time different from that of the factor(s) that affected Sertoli cell ␣ 2 -MG expression. These data illustrate that germ cells secrete multiple biological factors capable of regulating ␣ 2 -MG expression in the testis and the liver. In summary, this study reveals a possible physiological link between the testis and the liver in that germ cells may release a factor(s) capable of modulating ␣ 2 -MG expression in both organs.
Establishment and characterization of neonatal mouse sertoli cell lines
Journal of …, 2003
Sertoli cells isolated from 6-day postpartum mouse testes were conditionally immortalized with the simian virus 40 large tumor antigen gene (SV40-LTAg) under the control of a promoter inducible with ponasterone A, an analog of ecdysone. This strategy produced 2 cell lines, which exhibited mixed phenotypes. We first tested the conditional expression of the LTAg gene in the presence or absence of ponasterone A. The results showed that both cell lines expressed LTAg when the inducer was present in the culture media. When ponasterone A was removed, the majority of the cells died. After 60 generations, however, the continued expression of LTAg in the absence of the hormone indicated that unknown changes may have occurred in the genome of the cells. One of the cell lines was further subcloned, resulting in 7 new lines exhibiting a morphology resembling that of Sertoli cells in tissue culture. Reverse transcriptase-polymerase chain reaction (RT-PCR) was performed on RNA collected from each cell line in order to determine which cells were phenotypically similar to Sertoli cells in vivo. All cell lines expressed the products of the Sertoli cell-specific genes stem cell factor (SCF) and sulfated glycoprotein-2 (SGP-2), in addition to ␣-inhibin, GATA-1, and steroidogenic factor-1. Further, the lines express growth and differentiation factors known to act upon germ cells in vivo and in vitro such as leukemia inhibitory factor (LIF), transforming growth factor beta (TGF-), and basic fibroblast growth factor (bFGF). Moreover, when used as feeder layers in cocultures, at least 2 of these lines are able to maintain the viability of type A spermatogonia for at least 7 days and to support the first steps of spermatogonial differentiation.
Proceedings of the National Academy of Sciences, 1982
The accumulation of two polypeptides, SCml and SCm2, in the medium of Sertoli cell cultures is enhanced by follicle-stimulating hormone (FSH) but is unaffected by either the cAMP analog, N6,0-dibutyryl cAMP or luteinizing hormone. The assigned molecular weights of SCm1 and SCm2 differ from those of androgen-binding protein subunits or any other previously identified Sertoli cell secretory product. Incubation of Sertoli cell cultures with either FSH or N6,02'-dibutyryl cAMP also stimulates the incorporation of [rS]methionine into two intracellular polypeptides, SCc1 and SCc2. In addition, the phosphorylation of three intracellular polypeptides, SCc3, SCc4, and SCc5, is intensified when Sertoli cell cultures are treated with either FSH or N6,02'-dibutyryl cAMP. Based on these results and on previous work, we conclude that (i) SCmI and SCm2 may, like androgen-binding protein, be secreted by Sertoli cells and function extracellularly while SCcI and SCc2 are involved in FSH-dependent intracellular activity; (ii) SCc3, SCc4, and SCc5 are possible substrates for FSH-stimulated, cAMP-dependent protein kdnase activity; and (iii) SCc5 is an isoelectric variant of vimentintype intermediate filament protein presumably involved in FSHand N6,02'-dibutyryl cAMP-induced Sertoli cell shape changes.