Peritubular cells of the human testis: prostaglandin E
            2
            and more

Context: Fibrotic remodeling, especially of the tubule wall, in testes of infertile men is common, but reasons or consequences of these striking changes are not known. Based on cell culture and ex vivo studies, we previously suggested that mast cells via their products tryptase and histamine are involved in the development of fibrosis. However, studies in a relevant human testicular model are required to further test this hypothesis and the mechanisms of testicular fibrosis in general. Objective: The objective of the study was the isolation, culture, and characterization of adult human testicular peritubular cells. Patients and Interventions: Peritubular cells were obtained from biopsies of men suffering from obstructive azoospermia (n = 8) and varicocele (n = 2) but displaying normal spermatogenesis. Results: Explant cultures were obtained from all biopsies. Immunostaining of the cultured cells and corresponding paraffin-embedded tissues with antibodies against markers of fibroblasts (CD90/Thy-1) and smooth muscle cells (α-smooth muscle actin) clearly proved their origin from the peritubular region. These cells displayed morphological features of myofibroblasts, and gene array analyses as well as immunohistochemistry revealed the predominant expression of extracellular matrix genes and genes coding for basement membrane components. The cultured cells retain receptors for the major mast cell products histamine and tryptase. The addition of histamine (100 μm) and the tryptase agonist peptide SLIGKV (10 μm) resulted in a transient increase in intracellular calcium levels, confirming the functionality of the receptors. Conclusions: We conclude that human peritubular cells are a novel model for the investigation of paracrine, including mast cell initiated, interactions in the human testis, which will allow the study of fibrotic processes underlying male idiopathic infertility.

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Proteomic Insights into Senescence of Testicular Peritubular Cells from a Nonhuman Primate Model

Cells ◽

10.3390/cells9112498 ◽

2020 ◽

Vol 9 (11) ◽

pp. 2498

Author(s):

Jan B. Stöckl ◽

Nina Schmid ◽

Florian Flenkenthaler ◽

Charis Drummer ◽

Rüdiger Behr ◽

...

Keyword(s):

Nonhuman Primate ◽

Human Testis ◽

Nonhuman Primate Model ◽

Primate Model ◽

Morphological Alterations ◽

Age Related ◽

Cell Niche ◽

Peritubular Cells

Age-related changes in the human testis may include morphological alterations, disturbed steroidogenesis, and impaired spermatogenesis. However, the specific impact of cell age remains poorly understood and difficult to assess. Testicular peritubular cells fulfill essential functions, including sperm transport, contributions to the spermatogonial stem cell niche, and paracrine interactions within the testis. To study their role in age-associated decline of testicular functions, we performed comprehensive proteome and secretome analyses of repeatedly passaged peritubular cells from Callithrix jacchus. This nonhuman primate model better reflects the human testicular biology than rodents and further gives access to young donors unavailable from humans. Among 5095 identified proteins, 583 were differentially abundant between samples with low and high passage numbers. The alterations indicate a reduced ability of senescent peritubular cells to contract and secrete proteins, as well as disturbances in nuclear factor (NF)-κB signaling and a reduced capacity to handle reactive oxygen species. Since this in vitro model may not exactly mirror all molecular aspects of in vivo aging, we investigated the proteomes and secretomes of testicular peritubular cells from young and old donors. Even though the age-related alterations at the protein level were less pronounced, we found evidence for impaired protein secretion, altered NF-κB signaling, and reduced contractility of these in vivo aged peritubular cells.

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Ca2+ Signaling and IL-8 Secretion in Human Testicular Peritubular Cells Involve the Cation Channel TRPV2

International Journal of Molecular Sciences ◽

10.3390/ijms19092829 ◽

2018 ◽

Vol 19 (9) ◽

pp. 2829 ◽

Cited By ~ 6

Author(s):

Katja Eubler ◽

Carola Herrmann ◽

Astrid Tiefenbacher ◽

Frank-Michael Köhn ◽

J. Schwarzer ◽

...

Keyword(s):

Transient Receptor Potential ◽

Receptor Potential ◽

Transient Receptor Potential Channel ◽

Ruthenium Red ◽

Cation Channel ◽

Angiogenic Factor ◽

Human Testis ◽

Seminiferous Tubules ◽

Protein Levels ◽

Peritubular Cells

Peritubular cells are part of the wall of seminiferous tubules in the human testis and their contractile abilities are important for sperm transport. In addition, they have immunological roles. A proteomic analysis of isolated human testicular peritubular cells (HTPCs) revealed expression of the transient receptor potential channel subfamily V member 2 (TRPV2). This cation channel is linked to mechano-sensation and to immunological processes and inflammation in other organs. We verified expression of TRPV2 in peritubular cells in human sections by immunohistochemistry. It was also found in other testicular cells, including Sertoli cells and interstitial cells. In cultured HTPCs, application of cannabidiol (CBD), a known TRPV2 agonist, acutely induced a transient increase in intracellular Ca2+ levels. These Ca2+ transients could be blocked both by ruthenium red, an unspecific Ca2+ channel blocker, and tranilast (TRA), an antagonist of TRPV2, and were also abolished when extracellular Ca2+ was removed. Taken together this indicates functional TRPV2 channels in peritubular cells. When applied for 24 to 48 h, CBD induced expression of proinflammatory factors. In particular, mRNA and secreted protein levels of the proinflammatory chemokine interleukin-8 (IL-8/CXCL8) were elevated. Via its known roles as a major mediator of the inflammatory response and as an angiogenic factor, this chemokine may play a role in testicular physiology and pathology.

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Exploring Human Testicular Peritubular Cells: Identification of Secretory Products and Regulation by Tumor Necrosis Factor-α

Endocrinology ◽

10.1210/en.2007-1064 ◽

2008 ◽

Vol 149 (4) ◽

pp. 1678-1686 ◽

Cited By ~ 68

Author(s):

Christoph Schell ◽

Martin Albrecht ◽

Christine Mayer ◽

J. Ullrich Schwarzer ◽

Monica B. Frungieri ◽

...

Keyword(s):

Nerve Growth Factor ◽

Growth Factor ◽

Cyclooxygenase 2 ◽

Time Dependent ◽

Human Testis ◽

Dependent Manner ◽

Phenotypic Characteristics ◽

Nerve Growth ◽

Tnf Α ◽

Peritubular Cells

Testicular peritubular cells are myofibroblastic cells, which represent the major cellular components of the wall of the seminiferous tubules. In men their phenotypic characteristics, including possible secretory activity and regulation, are not well known, in neither normal nor pathologically altered testes. Especially in testes of men with impaired spermatogenesis, the cytoarchitecture of the tubular wall is frequently remodeled and presents fibrotic thickening, increased innervation, and infiltration by macrophages and mast cells. The latter are two sources of TNF-α. The purpose of our study was to explore human testicular peritubular cells and mechanisms of their regulation. To this end we primarily studied cultured human testicular peritubular cells (HTPCs), isolated from adult human testes. Having established that HTPCs express TNF-α receptors 1 and 2 and respond to recombinant human TNF-α by a rapid phosphorylation of ERK1/2, we used complementary approaches, including gene array/RT-PCR studies, Western blotting/immunocytochemistry, and ELISA techniques to study phenotypic characteristics of HTPCs and actions of TNFα. We found that HTPCs express the nerve growth factor gene and TNF-α-stimulated mRNA levels and secretion of nerve growth factor in a dose- and time-dependent manner. Similarly, monocyte chemoattractant protein-1 was identified as a product of HTPCs, which was regulated by TNF-α in a concentration- and time-dependent manner. TNF-α furthermore strongly enhanced expression and/or synthesis of other inflammatory molecules, namely IL-6 and cyclooxygenase-2. Active cyclooxygenase-2 is indicated by increased prostaglandin D2 levels. In addition, intercellular adhesion molecule-1, which was not detected at protein level in the absence of TNF-α, was induced upon TNF-α stimulation. In conclusion, these results provide novel insights into the nature of human peritubular cells, which are able to secrete potent signaling molecules and are regulated by TNF-α. These results also hint to an as-yet-unknown role of peritubular cells in normal human testis and involvement in the pathomechanisms associated with impaired spermatogenesis in men.

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Actin Like Filaments in the Peritubular Cells of Human Testis Chemical Extraction and Binding with Heavy Meromyosin

Andrologia ◽

10.1111/j.1439-0272.1977.tb01687.x ◽

2009 ◽

Vol 9 (4) ◽

pp. 349-356 ◽

Cited By ~ 5

Author(s):

S. FURUYA ◽

Y. KUMAMOTO ◽

T. SUZUKI ◽

M. TAKAUJI ◽

T. NAGAI

Keyword(s):

Chemical Extraction ◽

Human Testis ◽

Heavy Meromyosin ◽

Peritubular Cells

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Insights into replicative senescence of human testicular peritubular cells

Scientific Reports ◽

10.1038/s41598-019-51380-w ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 7

Author(s):

Nina Schmid ◽

Florian Flenkenthaler ◽

Jan B. Stöckl ◽

Kim-Gwendolyn Dietrich ◽

Frank M. Köhn ◽

...

Keyword(s):

Replicative Senescence ◽

Ion Beam ◽

Immune Surveillance ◽

Human Testis ◽

Mrna Levels ◽

Dipeptidyl Peptidase 4 ◽

Telomere Attrition ◽

Age Related ◽

Peritubular Cells

Abstract There is evidence for an age-related decline in male reproductive functions, yet how the human testis may age is not understood. Human testicular peritubular cells (HTPCs) transport sperm, contribute to the spermatogonial stem cell (SSC) niche and immune surveillance, and can be isolated and studied in vitro. Consequences of replicative senescence of HTPCs were evaluated to gain partial insights into human testicular aging. To this end, early and advanced HTPC passages, in which replicative senescence was indicated by increased cell size, altered nuclear morphology, enhanced β-galactosidase activity, telomere attrition and reduced mitochondrial DNA (mtDNA), were compared. These alterations are typical for senescent cells, in general. To examine HTPC-specific changes, focused ion beam scanning electron microscopy (FIB/SEM) tomography was employed, which revealed a reduced mitochondrial network and an increased lysosome population. The results coincide with the data of a parallel proteomic analysis and indicate deranged proteostasis. The mRNA levels of typical contractility markers and growth factors, important for the SSC niche, were not significantly altered. A secretome analysis identified, however, elevated levels of macrophage migration inhibitory factor (MIF) and dipeptidyl peptidase 4 (DPP4), which may play a role in spermatogenesis. Testicular DPP4 may further represent a possible drug target.

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The Presence of Colony-Stimulating Factor-1 and Its Receptor in Different Cells of the Testis; It Involved in the Development of Spermatogenesis In Vitro

International Journal of Molecular Sciences ◽

10.3390/ijms22052325 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2325

Author(s):

Alaa Sawaied ◽

Eden Arazi ◽

Ahmad AbuElhija ◽

Eitan Lunenfeld ◽

Mahmoud Huleihel

Keyword(s):

Testicular Tissue ◽

Culture Conditions ◽

Human Testis ◽

Seminiferous Tubules ◽

Colony Stimulating Factor ◽

Protein Levels ◽

Stimulating Factor ◽

Peritubular Cells ◽

Testicular Macrophages

Spermatogenesis is a complex process, in which spermatogonial cells proliferate and differentiate in the seminiferous tubules of the testis to generate sperm. This process is under the regulation of endocrine and testicular paracrine/autocrine factors. In the present study, we demonstrated that colony stimulating factor-1 (CSF-1) is produced by mouse testicular macrophages, Leydig, Sertoli, peritubular cells and spermatogonial cells (such as CDH1-positively stained cells; a marker of spermatogonial cells). In addition, we demonstrated the presence of CSF-1 and its receptor (CSF-1R) in testicular macrophages, Leydig, Sertoli, peritubular cells and spermatogonial cells of human testis. We also show that the protein levels of CSF-1 were the highest in testis of 1-week-old mice and significantly decreased with age (2–12-week-old). However, the transcriptome levels of CSF-1 significantly increased in 2–3-week-old compared to 1-week-old, and thereafter significantly decreased with age. On the other hand, the transcriptome levels of CSF-1R was significantly higher in mouse testicular tissue of all examined ages (2–12-week-old) compared to 1-week-old. Our results demonstrate the involvement of CSF-1 in the induction the proliferation and differentiation of spermatogonial cells to meiotic and postmeiotic stages (BOULE- and ACROSIN-positive cells) under in vitro culture conditions, using methylcellulose culture system (MCS). Thus, it is possible to suggest that CSF-1 system, as a testicular paracrine/autocrine system, is involved in the development of different stages of spermatogenesis and may be used in the development of future therapeutic strategies for treatment of male infertility.

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