Influence of hormonal imbalance on the integrity of seminiferous epithelium in the testes of adult rats chronically exposed to letrozole and rats exposed to soya isoflavones during the prenatal period, lactation, and up to sexual maturity

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 βA-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-1β (IL-1β) 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-1α 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-1α , in addition to FSH/cAMP, under the influence of the developing spermatogenic cells.

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Regulation of BTB Dynamics in Spermatogenesis—Insights From the Adjudin Model

Toxicological Sciences ◽

10.1093/toxsci/kfz180 ◽

2019 ◽

Vol 172 (1) ◽

pp. 75-88 ◽

Cited By ~ 6

Author(s):

Bai-Ping Mao ◽

Linxi Li ◽

Ming Yan ◽

Renshan Ge ◽

Qingquan Lian ◽

...

Keyword(s):

Germ Cell ◽

Low Dose ◽

Mammalian Target Of Rapamycin ◽

Underlying Mechanism ◽

Seminiferous Epithelium ◽

Regulatory Proteins ◽

Cell Organelles ◽

Adult Rats ◽

Downstream Signaling ◽

Cellular Events

Abstract During spermatogenesis, cell organelles, and germ cells, most notably haploid spermatids, are transported across the seminiferous epithelium so that fully developed spermatids line-up at the edge of the tubule lumen to undergo spermiation at stage VIII of the cycle. Studies have suggested that the microtubule (MT)-based cytoskeleton is necessary to support these cellular events. However, the regulatory molecule(s) and underlying mechanism(s) remain poorly understood. Herein, we sought to better understand this event by using an adjudin-based animal model. Adult rats were treated with adjudin at low-dose (10 mg/kg b.w.) which by itself had no notable effects on spermatogenesis. Rats were also treated with low-dose adjudin combined with overexpression of 2 endogenously produced blood-testis barrier (BTB) modifiers, namely rpS6 (ribosomal protein S6, the downstream signaling protein of mammalian target of rapamycin complex 1 [mTORC1]) and F5-peptide (a biological active peptide released from laminin-γ3 chain at the Sertoli-spermatid interface) versus the 2 BTB modifiers alone. Overexpression of these 2 BTB modifiers in the testis was shown to enhance delivery of adjudin to the testis, effectively inducing disruptive changes in MT cytoskeletons, causing truncation of MT conferred tracks that led to their collapse across the epithelium. The net result was massive germ cell exfoliation in the tubules, disrupting germ cell transport and cell adhesion across the seminiferous epithelium that led to aspermatogenesis. These changes were the result of disruptive spatial expression of several MT-based regulatory proteins. In summary, MT cytoskeleton supported by the network of MT regulatory proteins is crucial to maintain spermatogenesis.

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Transcriptional Profiling of the Hormone-Responsive Stages of Spermatogenesis Reveals Cell-, Stage-, and Hormone-Specific Events

Endocrinology ◽

10.1210/en.2009-0755 ◽

2009 ◽

Vol 150 (11) ◽

pp. 5074-5084 ◽

Cited By ~ 20

Author(s):

Liza O'Donnell ◽

Kyriakos Pratis ◽

Andrea Wagenfeld ◽

Ulrich Gottwald ◽

Jörg Müller ◽

...

Keyword(s):

Sertoli Cells ◽

Transcriptional Profiling ◽

Seminiferous Epithelium ◽

Cyclic Process ◽

Down Regulation ◽

Adult Rats ◽

Cell Stage ◽

Transcriptional Changes ◽

Pachytene Spermatocytes ◽

The Impact

Spermatogenesis occurs within the highly complex seminiferous epithelium. This cyclic process is accompanied by dynamic stage-specific transcriptional changes and is driven by androgens and FSH by mechanisms that are unclear. Here we report the impact of acute androgen and FSH suppression on the transcriptional dynamics of the seminiferous epithelium. We used transcriptional profiling to compare the most hormone-sensitive seminiferous epithelial stages (VII and VIII) from control and hormone-suppressed adult rats, together with publicly available datasets to delineate stage- and cell-specific transcriptional changes. The analyses reveal that, in these stages, there was a hormone-responsive down-regulation of spermatogonial and Sertoli cell transcripts maximally expressed in the earlier spermatogenic stages (I–VI). Transcripts expressed in Sertoli cells from stage VII and beyond were both up- and down-regulated by hormone suppression, with lysosome function, immune system-related genes, and lipid metabolism predicted to be hormone responsive. Hormone-responsive genes with putative roles in integrin-mediated cell adhesion were also identified. In pachytene spermatocytes, there was an initiation of transcription likely important for the completion of meiosis. A transcriptional switch in round spermatids was observed, from a hormone-responsive down-regulation of transcripts expressed in steps 1–7 spermatids to a hormone-independent up-regulation of transcripts expressed in steps 8–11 and likely involved in spermatid differentiation and DNA compaction. This study points to the existence of hormone-responsive global transcriptional repressors in Sertoli cells, spermatogonia, and spermatids and reveals novel and diverse cell-specific responses of the seminiferous epithelium to hormone suppression.

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Seminiferous epithelium damage after short period of busulphan treatment in adult rats and vitamin B12efficacy in the recovery of spermatogonial germ cells

International Journal of Experimental Pathology ◽

10.1111/iep.12195 ◽

2016 ◽

Vol 97 (4) ◽

pp. 317-328 ◽

Cited By ~ 7

Author(s):

Sandi Regina Vasiliausha ◽

Flávia Luciana Beltrame ◽

Fabiane de Santi ◽

Paulo Sérgio Cerri ◽

Breno Henrique Caneguim ◽

...

Keyword(s):

Germ Cells ◽

Seminiferous Epithelium ◽

Adult Rats ◽

Short Period

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Glycoprotein Synthesis in Sertoli Cells During the Cycle of the Seminiferous Epithelium of Adult Rats: A Radioautographic Study

Biology of Reproduction ◽

10.1095/biolreprod30.2.493 ◽

1984 ◽

Vol 30 (2) ◽

pp. 493-505 ◽

Cited By ~ 11

Author(s):

M. F. Lalli ◽

X. -M. Tang ◽

Y Clermont

Keyword(s):

Sertoli Cells ◽

Seminiferous Epithelium ◽

Adult Rats ◽

Glycoprotein Synthesis

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Effects of Hydro-alcoholic Extract of Pumpkin Seeds on Oogenesis Pathway, Liver, and Kidney of Female Rats : The Effects of hydro-alcoholic extract of pumpkin

10.32592/ircmj.2020.22.9.139 ◽

2020 ◽

Keyword(s):

Sexual Maturity ◽

The Body ◽

Female Rats ◽

Alcoholic Extract ◽

Adult Rats ◽

Pumpkin Seed ◽

Immature Rats ◽

Pumpkin Seeds ◽

Group 3 ◽

Experimental Group

Background and Objectives: Pumpkin seed extract can be a good alternative to hormone replacement therapy since it is rich in phytoestrogens. In this regard, the present research aimed to investigate the effect of hydro-alcoholic extract of pumpkin seeds on the oogenesis pathway, liver, and kidney of female rats. Materials and Methods: This experimental study was performed on 64 Wistar female rats (including 32 adults and 32 immature rats). The adult rats were randomly divided into three experimental and one control groups (n=8 per group). Moreover, the immature rats were allocated to groups in a similar manner. The experimental groups 1, 2, and 3 received a hydro-alcoholic extract of pumpkin seed in doses of 20, 50, 100 mg/kg, respectively, via intraperitoneal injection for 21 consecutive days. For the purposes of the study, blood samples were taken one day after the last injection to determine the serum levels of female hormones as well as renal and hepatic factors. The ovaries, livers, and kidneys of the rats were also separated for histological tests. Results: Based on the results, significant increases were observed in the bodyweight of all immature rats; estrogen levels in the adult experimental group 3 and immature experimental groups 2 and 3; progesterone and creatinine levels in the immature experimental group 3; aspartate aminotransferase, total protein, unstable angina (UA), and the renal diameter in the immature experimental groups 1 and 2; follicle-stimulating hormone in the adult experimental group 3 and the immature experimental groups 1 and 2; luteinizing hormone and Graafian follicles in the adult experimental group 3; and atretic follicles in the immature experimental group 1 and 3 (P<0.05). Moreover, significant decreases were observed in the alkaline phosphatase in the adult experimental group 3; total protein, UA, and renal diameter in the immature experimental group 3; diameters of proximal and distal tubule as well as Henle’s loop in all immature rats; diameter of glomerular in the immature experimental groups 1 and 2; diameter of the renal cortex, glomerular, and Bowman's capsule in the adult experimental groups 2 and 3; secondary follicles in the adult experimental group 1, immature experimental groups 1 and 3; and primitive and early follicles in all the adult rats, compared with the control group (P<0.05). Conclusion: Based on the findings, it can be concluded that the pumpkin seeds provide the nutritional needs of the body at the onset of sexual maturity, prepare the body for sexual maturity, and regulate female sex hormones without having adverse effects on the hepatic tissues. However, it must be noted that its consumption at the onset of sexual maturity requires dosage determination and further studies.

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