Evidence that α5β1 integrins mediate Leydig cell binding to fibronectin and enhance Leydig cell proliferation stimulated by a Sertoli cell-secreted mitogenic factor in vitro

Abstract STUDY QUESTION What are the consequences of ageing on human Leydig cell number and hormonal function? SUMMARY ANSWER Leydig cell number significantly decreases in parallel with INSL3 expression and Sertoli cell number in aged men, yet the in vitro Leydig cell androgenic potential does not appear to be compromised by advancing age. WHAT IS KNOWN ALREADY There is extensive evidence that ageing is accompanied by decline in serum testosterone levels, a general involution of testis morphology and reduced spermatogenic function. A few studies have previously addressed single features of the human aged testis phenotype one at a time, but mostly in tissue from patients with prostate cancer. STUDY DESIGN, SIZE, DURATION This comprehensive study examined testis morphology, Leydig cell and Sertoli cell number, steroidogenic enzyme expression, INSL3 expression and androgen secretion by testicular fragments in vitro. The majority of these endpoints were concomitantly evaluated in the same individuals that all displayed complete spermatogenesis. PARTICIPANTS/MATERIALS, SETTING, METHODS Testis biopsies were obtained from 15 heart beating organ donors (age range: 19–85 years) and 24 patients (age range: 19–45 years) with complete spermatogenesis. Leydig cells and Sertoli cells were counted following identification by immunohistochemical staining of specific cell markers. Gene expression analysis of INSL3 and steroidogenic enzymes was carried out by qRT-PCR. Secretion of 17-OH-progesterone, dehydroepiandrosterone, androstenedione and testosterone by in vitro cultured testis fragments was measured by LC-MS/MS. All endpoints were analysed in relation to age. MAIN RESULTS AND THE ROLE OF CHANCE Increasing age was negatively associated with Leydig cell number (R = −0.49; P < 0.01) and concomitantly with the Sertoli cell population size (R= −0.55; P < 0.001). A positive correlation (R = 0.57; P < 0.001) between Sertoli cell and Leydig cell numbers was detected at all ages, indicating that somatic cell attrition is a relevant cellular manifestation of human testis status during ageing. INSL3 mRNA expression (R= −0.52; P < 0.05) changed in parallel with Leydig cell number and age. Importantly, steroidogenic capacity of Leydig cells in cultured testis tissue fragments from young and old donors did not differ. Consistently, age did not influence the mRNA expression of steroidogenic enzymes. The described changes in Leydig cell phenotype with ageing are strengthened by the fact that the different age-related effects were mostly evaluated in tissue from the same men. LIMITATIONS, REASONS FOR CAUTION In vitro androgen production analysis could not be correlated with in vivo hormone values of the organ donors. In addition, the number of samples was relatively small and there was scarce information about the concomitant presence of potential confounding variables. WIDER IMPLICATIONS OF THE FINDINGS This study provides a novel insight into the effects of ageing on human Leydig cell status. The correlation between Leydig cell number and Sertoli cell number at any age implies a connection between these two cell types, which may be of particular relevance in understanding male reproductive disorders in the elderly. However aged Leydig cells do not lose their in vitro ability to produce androgens. Our data have implications in the understanding of the physiological role and regulation of intratesticular sex steroid levels during the complex process of ageing in humans. STUDY FUNDING/COMPETING INTEREST(S) This work was supported by grants from Prin 2010 and 2017. The authors have no conflicts of interest. TRIAL REGISTRATION NUMBER N/A.

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Mandibular Appliance Modulates Condylar Growth through Integrins

Journal of Dental Research ◽

10.1177/154405910808700210 ◽

2008 ◽

Vol 87 (2) ◽

pp. 153-158 ◽

Cited By ~ 10

Author(s):

M. Rubia Marques ◽

D. Hajjar ◽

K. Gomes Franchini ◽

A. Sigari Moriscot ◽

M. Fagundes Santos

Keyword(s):

Cell Proliferation ◽

Cell Binding ◽

Cartilage Growth ◽

Condylar Cartilage ◽

Postural Changes ◽

Maxilla And Mandible ◽

Almost All ◽

Binding Sequence ◽

Immunohistochemical Analyses

Functional orthopedic therapy corrects growth discrepancies between the maxilla and mandible, possibly through postural changes in the musculature and modulation of the mandibular condylar cartilage growth. Using Wistar rats, we tested the hypothesis that chondrocytes respond to forces generated by a mandibular propulsor appliance by changes in gene expression, and that integrins are important mediators in this response. Immunohistochemical analyses demonstrated that the use of the appliance for different periods of time modulated the expression of fibronectin, α5 and αv integrin subunits, as well as cell proliferation in the cartilage. In vitro, cyclic distension of condylar cartilage-derived cells increased fibronectin mRNA, as well as Insulin-like Growth Factor-I and II mRNA and cell proliferation. A peptide containing the Arginine-Glycine-Asparagine sequence (RGD), the main cell-binding sequence in fibronectin, blocked almost all these effects, confirming that force itself modulates the growth of the rat condylar cartilage, and that RGD-binding integrins participate in mechanotransduction.

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Oncostatin M stimulates immature Leydig cell proliferation but inhibits its maturation and function in rats through JAK1/STAT3 signaling and induction of oxidative stress in vitro

Andrology ◽

10.1111/andr.13109 ◽

2021 ◽

Author(s):

Lili Tian ◽

Xueyun Li ◽

Yiyan Wang ◽

Quanxu Chen ◽

Xiaoheng Li ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Proliferation ◽

Leydig Cell ◽

Oncostatin M ◽

Stat3 Signaling ◽

And Function

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Daidzein impairs Leydig cell testosterone production and Sertoli cell function in neonatal mouse testes: An in vitro study

Molecular Medicine Reports ◽

10.3892/mmr.2016.5896 ◽

2016 ◽

Vol 14 (6) ◽

pp. 5325-5333 ◽

Cited By ~ 5

Author(s):

Yanfeng Zhu ◽

Hua Xu ◽

Min Li ◽

Zhibin Gao ◽

Jie Huang ◽

...

Keyword(s):

Sertoli Cell ◽

Leydig Cell ◽

Cell Function ◽

In Vitro Study ◽

Neonatal Mouse ◽

Vitro Study ◽

Testosterone Production

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Synergistic Effects of Sertoli Cell and FSH on Leydig Cell Function: In Vitro Study

Annals of the New York Academy of Sciences ◽

10.1111/j.1749-6632.1984.tb38374.x ◽

1984 ◽

Vol 438 (1 Hormonal Cont) ◽

pp. 684-687 ◽

Cited By ~ 3

Author(s):

M. BENAHMED ◽

J. REVENTOS ◽

E. TABONE ◽

J. M. SAEZ

Keyword(s):

Sertoli Cell ◽

Leydig Cell ◽

Cell Function ◽

Synergistic Effects ◽

In Vitro Study ◽

Vitro Study ◽

Leydig Cell Function

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Sertoli cell binding to isolated testicular basement membrane.

The Journal of Cell Biology ◽

10.1083/jcb.103.3.1109 ◽

1986 ◽

Vol 103 (3) ◽

pp. 1109-1119 ◽

Cited By ~ 14

Author(s):

G C Enders ◽

J H Henson ◽

C F Millette

Keyword(s):

Basement Membrane ◽

Sertoli Cell ◽

Basal Lamina ◽

Sertoli Cells ◽

Matrix Material ◽

Three Dimensional ◽

Myoid Cells ◽

Cell Binding

We have examined the adhesion of primary Sertoli cells to a seminiferous tubule basement membrane (STBM) preparation in vitro. The STBM isolation procedure (Watanabe, T.K., L.J. Hansen, N.K. Reddy, Y.S. Kanwar, and J.K. Reddy, 1984, Cancer Res., 44:5361-5368) yields segments of STBM that retain their histotypic form in both three-dimensional tubular geometry and ultrastructural appearance. The STBM sleeves contain two laminae: a thick, inner basal lamina that was formed in vivo between Sertoli cells and peritubular myoid cells; and a thinner, outer basal lamina that was formed between myoid cells and sinusoidal endothelial cells. Characterization by immunofluorescence and SDS PAGE revealed that the isolated STBM retained fibronectin, laminin, and putative type IV collagen among its many components. When the STBM sleeves were gently shaken with an enriched fraction of primary Sertoli cells, the Sertoli cells bound preferentially to the lumenal basal lamina at the ends of the STBM sleeves. Few Sertoli cells bound to either the outer basal lamina of the STBM sleeves or to vascular extracellular matrix material which contaminated the STBM preparation. 3T3 cells, in contrast, bound to all surfaces of the STBM sleeves. Pretreatment of the STBM sleeves with proteases, 0.1 M Na metaperiodate, 4 M guanidine HCl, or heating to 80 degrees-90 degrees C inhibited lumenal Sertoli cell binding, but binding was not inhibited by chondroitinase ABC, heparinase, hyaluronidase, or 4 M NaCl. The lumenal Sertoli cell binding occurred in the presence or absence of added soluble laminin, but not fibronectin. The addition of soluble laminin, but not fibronectin, restored random binding of Sertoli cells to trypsinized STBM sleeves. Our in vitro model system indicates that Sertoli cells recognize differences in two basal laminae produced in vivo on either side of myoid cells.

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