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English AM, Byrne CJ, Cormican P, Waters SM, Fair S, Kenny DA. Effect of Early Calf-Hood Nutrition on the Transcriptional Regulation of the Hypothalamic-Pituitary-Testicular axis in Holstein-Friesian Bull Calves. Sci Rep 2018; 8:16577. [PMID: 30409985 PMCID: PMC6224434 DOI: 10.1038/s41598-018-34611-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2017] [Accepted: 09/28/2018] [Indexed: 12/16/2022] Open
Abstract
The aim of this study was to investigate the effect of early calf-hood nutrition on the transcriptomic profile of the arcuate nucleus of the hypothalamus, anterior pituitary and testes in Holstein-Friesian bulls. Holstein-Friesian bull calves with a mean (±S.D.) age and bodyweight of 19 (±8.2) days and 47.5 (±5.3) kg, respectively, were offered a high (n = 10) or low (n = 10) plane of nutrition in order to achieve an overall growth rate of 1.2 and 0.5 kg/day. At 126 (±3) days of age, calves were euthanized, hypothalamus (arcuate region), anterior pituitary and testicular parenchyma samples were harvested and RNAseq analysis was performed. There were 0, 49 and 1,346 genes differentially expressed in the arcuate nucleus, anterior pituitary and testicular tissue of bull calves on the low relative to the high plane of nutrition, respectively (P < 0.05; False Discovery Rate <0.05). Cell cycle processes in the anterior pituitary were down regulated in the low relative to the high plane of nutrition; there was no differential expression of genes related to reproductive processes. Gene expression involved in cholesterol and androgen biosynthesis in the testes were down regulated in animals on the low plane of nutrition. This study provides insight into the effect of early life plane of nutrition on the regulation of the HPT axis.
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Affiliation(s)
- A M English
- Animal and Bioscience Research Department, Teagasc Grange, Dunsany, C15 PW93, Co. Meath, Ireland.,Laboratory of Animal Reproduction, Department of Biological Sciences, University of Limerick, V94 T9PX, Limerick, Ireland
| | - C J Byrne
- Animal and Bioscience Research Department, Teagasc Grange, Dunsany, C15 PW93, Co. Meath, Ireland.,School of Agriculture and Food Science, University College Dublin, Belfield, D04 N2E5, Dublin, Ireland
| | - P Cormican
- Animal and Bioscience Research Department, Teagasc Grange, Dunsany, C15 PW93, Co. Meath, Ireland
| | - S M Waters
- Animal and Bioscience Research Department, Teagasc Grange, Dunsany, C15 PW93, Co. Meath, Ireland
| | - S Fair
- Laboratory of Animal Reproduction, Department of Biological Sciences, University of Limerick, V94 T9PX, Limerick, Ireland
| | - D A Kenny
- Animal and Bioscience Research Department, Teagasc Grange, Dunsany, C15 PW93, Co. Meath, Ireland. .,School of Agriculture and Food Science, University College Dublin, Belfield, D04 N2E5, Dublin, Ireland.
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Saewu A, Kadunganattil S, Raghupathy R, Kongmanas K, Diaz-Astudillo P, Hermo L, Tanphaichitr N. Clusterin in the mouse epididymis: possible roles in sperm maturation and capacitation. Reproduction 2017; 154:867-880. [DOI: 10.1530/rep-17-0518] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 08/17/2017] [Accepted: 10/02/2017] [Indexed: 01/23/2023]
Abstract
Clusterin (CLU) is known as an extracellular chaperone for proteins under stress, thus preventing them from aggregation and precipitation. We showed herein that CLU, expressed by principal cells of the mouse caput epididymis, was present in high amounts in the lumen. In the cauda epididymis, CLU bound tightly to the sperm head surface and its amount on total sperm was similar to that in the bathing luminal fluid. In both immotile and motile caudal epididymal sperm, CLU was localized over the entire sperm head except at the convex ridge, although in the motile sperm population, the CLU immunofluorescence pattern was distinctively mottled with a lower intensity. However, when motile sperm became capacitated, CLU was relocalized to the head hook region, with immunofluorescence intensity being higher than that on the non-capacitated counterparts. Under a slightly acidic pH of the epididymal lumen, CLU may chaperone some luminal proteins and deliver them onto the sperm surface. Immunoprecipitation of epididymal fluid proteins indicated that CLU interacted with SED1, an important egg-binding protein present in a high amount in the epididymal lumen. In a number of non-capacitated sperm, fractions of SED1 and CLU co-localized, but after capacitation, SED1 and CLU dissociated from one another. While CLU moved to the sperm head hook, SED1 translocated to the head convex ridge, the egg-binding site. Overall, CLU localization patterns can serve as biomarkers of immotile sperm, and non-capacitated and capacitated sperm in mice. The chaperone role of CLU may also be important for sperm maturation and capacitation.
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Setarehbadi R, Vatannejad A, Vaisi-Raygani A, Amiri I, Esfahani M, Fattahi A, Tavilani H. Apolipoprotein E genotypes of fertile and infertile men. Syst Biol Reprod Med 2012; 58:263-7. [PMID: 22568769 DOI: 10.3109/19396368.2012.684134] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Lipid components of spermatozoa have an important role in the functional activity of this cell. The protein, apolipoprotein E (apoE), has a central role in lipid transport. The aim of this study was to investigate the distribution of APOE genotypes, ϵ3ϵ3, ϵ3ϵ4, and ϵ2ϵ3, and the corresponding alleles in fertile and infertile males, and to assess the semen parameters from the patients carrying the different alleles. In addition, the levels of cholesterol, phospholipid, and triacylglycerol in spermatozoa, isolated by PureSperm gradient and from seminal plasma in samples from infertile males was compared with respect to the APOE genotype. APOE genotypes were determined by PCR-RFLP on DNA extracted from peripheral blood leucocytes in 108 fertile and 107 infertile men. There was a significant difference between the distribution of APOE genotypes in fertile as compared to infertile males (χ(2) = 9.1, df = 2, p = 0.011). The presence of genotype ϵ3ϵ4 conferred a 3.82 risk factor for male infertility {Odds ratio = 3.82 (1.46-10, p = 0.006)}. Our findings showed that the distribution of APOE genotypes and alleles differed between fertile and infertile individuals and may be a risk factor for male infertility. We suggest that the effects of APOE genotypes may be linked to differences in the efficacy of the expressed apoE isoforms in promoting sperm maturation during epididymal transit.
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Affiliation(s)
- Rohollah Setarehbadi
- Department of Biochemistry, Medical School, Hamadan University of Medical Sciences, Hamadan, Iran
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Asano A, Nelson JL, Zhang S, Travis AJ. Characterization of the proteomes associating with three distinct membrane raft sub-types in murine sperm. Proteomics 2011; 10:3494-505. [PMID: 20815087 DOI: 10.1002/pmic.201000002] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Mammalian sperm are transcriptionally and translationally inactive. To meet changing needs in the epididymis and female tract, they rely heavily on post-translational modifications and protein acquisition/degradation. Membrane rafts are sterol and sphingolipid-enriched micro-domains that organize and regulate various pathways. Rafts have significance in sperm by transducing the stimulus of sterol efflux into changes in intracellular signaling that confer fertilization competence. We recently characterized three biochemically distinct sub-types of sperm rafts, and now present profiles for proteins targeting to and associating with these sub-types, along with a fraction largely comprised of "non-raft" domains. Proteomics analysis using a gel-based LC-MS/MS approach identified 190 strictly validated proteins in the raft sub-types. Interestingly, many of these are known to be expressed in the epididymis, where sperm membrane composition matures. To investigate potential roles for rafts in epididymal protein acquisition, we compared the expression and localization of two different sterol-interacting proteins, apolipoprotein-A1 (apoA1) and prominin-1 (prom1) in sperm from different zones. We found that apoA1 was gradually added to the plasma membrane overlying the acrosome, whereas prom1 was not, suggesting different mechanisms for raft protein acquisition. Our results define raft-associating proteins, demonstrate functional similarities and differences among raft sub-types, and provide insights into raft-mediated epididymal protein acquisition.
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Affiliation(s)
- Atsushi Asano
- The Baker Institute for Animal Health, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA
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Hermo L, Pelletier RM, Cyr DG, Smith CE. Surfing the wave, cycle, life history, and genes/proteins expressed by testicular germ cells. Part 5: intercellular junctions and contacts between germs cells and Sertoli cells and their regulatory interactions, testicular cholesterol, and genes/proteins associated with more than one germ cell generation. Microsc Res Tech 2010; 73:409-94. [PMID: 19941291 DOI: 10.1002/jemt.20786] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In the testis, cell adhesion and junctional molecules permit specific interactions and intracellular communication between germ and Sertoli cells and apposed Sertoli cells. Among the many adhesion family of proteins, NCAM, nectin and nectin-like, catenins, and cadherens will be discussed, along with gap junctions between germ and Sertoli cells and the many members of the connexin family. The blood-testis barrier separates the haploid spermatids from blood borne elements. In the barrier, the intercellular junctions consist of many proteins such as occludin, tricellulin, and claudins. Changes in the expression of cell adhesion molecules are also an essential part of the mechanism that allows germ cells to move from the basal compartment of the seminiferous tubule to the adluminal compartment thus crossing the blood-testis barrier and well-defined proteins have been shown to assist in this process. Several structural components show interactions between germ cells to Sertoli cells such as the ectoplasmic specialization which are more closely related to Sertoli cells and tubulobulbar complexes that are processes of elongating spermatids embedded into Sertoli cells. Germ cells also modify several Sertoli functions and this also appears to be the case for residual bodies. Cholesterol plays a significant role during spermatogenesis and is essential for germ cell development. Lastly, we list genes/proteins that are expressed not only in any one specific generation of germ cells but across more than one generation.
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Affiliation(s)
- Louis Hermo
- Faculty of Medicine, Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec, Canada H3A 2B2.
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Abstract
Consideration of the function of the epididymis has undergone profound changes over the last century during which it has moved from a largely neglected male reproductive organ to one that is an increasingly exploited source of sperm for assisted reproduction strategies. From histological studies in the lizard1 it was considered that, ‘…the cells lining the epididymal canal produce a material necessary for the spermatozoa during their passage through the organ …’ whereas a fertility study with guinea-pigs stated boldly that, ‘… changes undergone [by spermatozoa in the epididymis] are not conditioned by some specific action of epididymal secretion …’. The former view found favour in a review of the literature which concluded that, ‘… there are specific epididymal secretions necessary for sperm maturation and survival …’, although the nature of the secretions were not then known. However, this concept, currently held by most of those studying the epididymis of animals, was again contradicted on the basis of clinical work: ‘… it certainly is possible for sperm that have never passed through any length of the epididymis at all to mature on their own …’.
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Ouvrier A, Cadet R, Vernet P, Laillet B, Chardigny JM, Lobaccaro JMA, Drevet JR, Saez F. LXR and ABCA1 control cholesterol homeostasis in the proximal mouse epididymis in a cell-specific manner. J Lipid Res 2009; 50:1766-75. [PMID: 19395734 DOI: 10.1194/jlr.m800657-jlr200] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Mammalian spermatozoa undergo important plasma membrane maturation steps during epididymal transit. Among these, changes in lipids and cholesterol are of particular interest as they are necessary for fertilization. However, molecular mechanisms regulating these transformations inside the epididymis are still poorly understood. Liver X receptors (LXRs), the nuclear receptors for oxysterols, are of major importance in intracellular cholesterol homeostasis, and LXR(-/-)-deficient male mice have already been shown to have reduced fertility at an age of 5 months and complete sterility for 9-month-old animals. This sterility phenotype is associated with testes and caput epididymides epithelial defects. The research presented here was aimed at investigating how LXRs act in the male caput epididymidis by analyzing key actors in cholesterol homeostasis. We show that accumulation of cholesteryl esters in LXR(-/-) male mice is associated with a specific loss of ABCA1 and an increase in apoptosis of apical cells of the proximal caput epididymidis. ATP-binding cassette G1 (ABCG1) and scavenger receptor B1 (SR-B1), two other cholesterol transporters, show little if any modifications. Our study also revealed that SR-B1 appears to have a peculiar expression pattern along the epididymal duct. These results should help in understanding the functional roles of LXR in cholesterol trafficking processes in caput epididymidis.
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Affiliation(s)
- Aurélia Ouvrier
- Université Blaise Pascal, Unité Mixte de Recherche GReD Centre National de la Recherche Scientifique 6247, INSERM U931, 63177 Aubiere, cedex, France
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Swarnakar S, Beers J, Strickland DK, Azhar S, Williams DL. The apolipoprotein E-dependent low density lipoprotein cholesteryl ester selective uptake pathway in murine adrenocortical cells involves chondroitin sulfate proteoglycans and an alpha 2-macroglobulin receptor. J Biol Chem 2001; 276:21121-8. [PMID: 11274190 DOI: 10.1074/jbc.m101691200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cells acquire lipoprotein cholesterol by receptor-mediated endocytosis and selective uptake pathways. In the latter case, lipoprotein cholesteryl ester (CE) is transferred to the plasma membrane without endocytosis and degradation of the lipoprotein particle. Previous studies with Y1/E/tet/2/3 murine adrenocortical cells that were engineered to express apolipoprotein (apo) E demonstrated that apoE expression enhances low density lipoprotein (LDL) CE uptake by both selective and endocytic pathways. The present experiments test the hypothesis that apoE-dependent LDL CE selective uptake is mediated by scavenger receptor, class B, type I (SR-BI). Surprisingly, SR-BI expression was not detected in the Y1/E/tet/2/3 clone of Y1 adrenocortical cells, indicating the presence of a distinct apoE-dependent pathway for LDL CE selective uptake. ApoE-dependent LDL CE selective uptake in Y1/E/tet/2/3 cells was inhibited by receptor-associated protein and by activated alpha(2)-macroglobulin (alpha(2)M), suggesting the participation of the LDL receptor-related protein/alpha(2)M receptor. Reagents that inhibited proteoglycan synthesis or removed cell surface chondroitin sulfate proteoglycan completely blocked apoE-dependent LDL CE selective uptake. None of these reagents inhibited SR-BI-mediated LDL CE selective uptake in the Y1-BS1 clone of Y1 cells in which LDL CE selective uptake is mediated by SR-BI. We conclude that LDL CE selective uptake in adrenocortical cells occurs via SR-BI-independent and SR-BI-dependent pathways. The SR-BI-independent pathway is an apoE-dependent process that involves both chondroitin sulfate proteoglycans and an alpha(2)M receptor.
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Affiliation(s)
- S Swarnakar
- Department of Pharmacological Sciences, University Medical Center, State University of New York, Stony Brook, New York 11794, USA
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Swarnakar S, Reyland ME, Deng J, Azhar S, Williams DL. Selective uptake of low density lipoprotein-cholesteryl ester is enhanced by inducible apolipoprotein E expression in cultured mouse adrenocortical cells. J Biol Chem 1998; 273:12140-7. [PMID: 9575160 DOI: 10.1074/jbc.273.20.12140] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Apolipoprotein (apo) E is expressed at high levels by steroidogenic cells of the adrenal gland, ovary, and testis. The cell surface location of apoE in adrenocortical cells suggests that apoE may facilitate the uptake of lipoprotein cholesterol by either the endocytic or the selective uptake pathways, or both. To examine these possibilities, the human apoE gene was expressed in murine Y1 adrenocortical cells under control of an inducible tetracycline-regulated promoter. The results show that induction of apoE yielded a 2-2.5-fold increase in the uptake of low density lipoprotein-cholesteryl ester (LDL-CE) but had little effect on high density lipoprotein-CE uptake. Analysis of lipoprotein uptake pathways showed that apoE increased LDL-CE uptake by both endocytic and selective uptake pathways. In terms of cholesterol delivery to the adrenal cell, the apoE-mediated enhancement of LDL-CE selective uptake was quantitatively more important. Furthermore, the predominant effect of apoE expression was on the low affinity component of LDL-CE selective uptake. LDL particles incubated with apoE-expressing cells contained 0.92 +/- 0.11 apoE molecules/apoB after gel filtration chromatography, indicating stable complex formation between apoE and LDL. ApoE expression by Y1 cells was necessary for enhanced LDL-CE selective uptake. This result may indicate an interaction between apoE-containing LDL and cell surface apoE. These data suggest that apoE produced locally by steroidogenic cells facilitates cholesterol acquisition by the LDL selective uptake pathway.
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Affiliation(s)
- S Swarnakar
- Department of Pharmacological Sciences, University Medical Center, State University of New York, Stony Brook, New York 11794, USA
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Leininger-Muller B, Siest G. The rat, a useful animal model for pharmacological studies on apolipoprotein E. Life Sci 1996; 58:455-67. [PMID: 8569418 DOI: 10.1016/0024-3205(95)02245-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Apolipoprotein E is a major protein component of lipoproteins and plays an important role in cholesterol transport. The structure of the gene and the polymorphism of apolipoprotein E have been studied in human and rat, which show similar structures of apolipoprotein E. The wide tissue distribution of this apolipoprotein suggests diverse functions like cholesterol distribution between cells, intracellular cholesterol trafficking and tissue reparation. Nevertheless, the presence of apolipoprotein E in atherosclerotic plaques and amyloid deposits in brains of Alzheimer's disease patients also indicate pathologic functions staying misunderstood. The aim of this paper is to review the present knowledge on the distribution of apolipoprotein E between the different organs with the related functions and to make an overview of the implications of this apolipoprotein is physiological events and pathological states in the rat. The rat is widely used for drug metabolism studies. Its serum levels are 5-10 times higher than in human and thus this animal provides an useful pharmacological model to elucidate the functions of apo E.
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Affiliation(s)
- B Leininger-Muller
- Centre du Médicament, Université Henri Poincaré, Nancy 1, CNRS URA 597, France
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Abstract
Quantitation of apoE has proved to be extremely useful in studies of the regulation of apoE synthesis and metabolism. Measurement of serum apoE and/or its distribution among the lipoprotein classes may have clinical utility, although this remains to be established. Some of the unique properties of apoE such as its genetic, chemical, and structural heterogeneity, its propensity to self-associate, and its ability to freely exchange on the surfaces of a wide variety of lipoprotein classes are factors that should be considered in measurements of apoE. The availability of commercial kits and reagents for human apoE quantitation make the development of apoE immunoassays readily achievable in most research and clinical laboratories.
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Affiliation(s)
- E S Krul
- Cardiovascular Disease Research Department, Searle Research and Development, Monsanto Company, St. Louis, Missouri 63167, USA
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12
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Fofana M, Maboundou JC, Bocquet J, Le Goff D. Transfer of cholesterol between high density lipoproteins and cultured rat Sertoli cells. Biochem Cell Biol 1996; 74:681-6. [PMID: 9018376 DOI: 10.1139/o96-074] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
In the testes, the Sertoli cells are separated from the blood capillaries by the basement membrane, thereby excluding the passage of low density lipoproteins (LDLs) but allowing the passage of high density lipoproteins (HDLs). The present study examines first the capacity of Sertoli cells to uptake cholesterol from HDL and secondly the role of apolipoproteins (apo) A-I and E in cholesterol flux between HDL and cultured rat Sertoli cells. In the presence of HDL in cultured medium, rat Sertoli cells accumulated few amounts of esterified cholesterol. Incubation of [14C] cholesterol-labelled Sertoli cells with [3H]cholesterol-labelled HDL showed that the amount of cholesterol influx slightly exceeded its efflux, thus resulting in a net uptake of cholesterol from HDL to rat Sertoli cells. The amount of HDL-cholesterol converted to steroids by Sertoli cells was about 32% of influx. Uptake of cholesterol by Sertoli cells was three times higher with phospholipid-apo A-I vesicles and seven times higher with phospholipid- apo E vesicles than that with phospholipid vesicles without apolipoprotein. Phospholipid- apo A-I vesicles promoted cholesterol efflux at the same rate as native HDL and twice as efficiently as phospholipid- apo E vesicles. Thus, this study shows that rat Sertoli cells have the capacity to take up HDL-cholesterol for membrane renewal and steroid production mainly by apo E dependent pathways.
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Affiliation(s)
- M Fofana
- Laboratoire de Biochimie, EP CNRS 009, Université de Caen, France
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Maboundou JC, Fofana M, Fresnel J, Bocquet J, Le Goff D. Effect of lipoproteins on cholesterol synthesis in rat Sertoli cells. Biochem Cell Biol 1995; 73:67-72. [PMID: 7662317 DOI: 10.1139/o95-008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Lipoprotein metabolism has been investigated in cultured rat Sertoli cells. Cells incubated with low-density lipoproteins (LDLs) or high-density lipoproteins (HDLs) showed a concentration-dependent decrease of sterol synthesis, indicating a net cholesterol delivery to the Sertoli cells. At 50 micrograms/mL, lipoproteins inhibited the incorporation of [14C]acetate into free cholesterol by 83% for the LDL and 47% for the HDL. Electron microscopic examinations of the Sertoli cells provide evidence of the internalization of gold-labelled HDL into coated pits and coated vesicles. Competitive studies between human LDL and rat HDL indicate that Sertoli cells take up cholesterol from LDL and HDL containing apolipoprotein (apo) E by common pathways. These results suggest that Sertoli cells possess apo B and E receptors for the uptake and degradation of LDL and HDL, although the basement membrane excludes the passage of LDL from blood capillaries to the Sertoli cells. At 50 micrograms/mL, apo-E-depleted HDL inhibited the incorporation of [14C]acetate into free cholesterol by 34%. Thus, this study shows that Sertoli cells are capable of taking up apo-E-depleted HDL cholesterol for cell metabolism.
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MESH Headings
- Acetates/metabolism
- Animals
- Apolipoproteins E/physiology
- Cells, Cultured
- Cholesterol/biosynthesis
- Cholesterol/metabolism
- Coated Pits, Cell-Membrane/metabolism
- Coated Pits, Cell-Membrane/ultrastructure
- Coated Vesicles/metabolism
- Coated Vesicles/ultrastructure
- Humans
- Lipoproteins, HDL/metabolism
- Lipoproteins, HDL/pharmacology
- Lipoproteins, LDL/metabolism
- Lipoproteins, LDL/pharmacology
- Male
- Microscopy, Immunoelectron
- Rats
- Rats, Sprague-Dawley
- Receptors, LDL/metabolism
- Sertoli Cells/drug effects
- Sertoli Cells/metabolism
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Affiliation(s)
- J C Maboundou
- Laboratoire de Biochimie, Université de Caen, France
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Cooper TG. Role of the epididymis in mediating changes in the male gamete during maturation. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1995; 377:87-101. [PMID: 7484449 DOI: 10.1007/978-1-4899-0952-7_6] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This article reviews recent knowledge about events occurring in the epididymis that are important for sperm to fertilise eggs. Well established concepts are stated without references (see Cooper, 1986 for older literature) but recent references are included where they throw light on mechanisms of epididymal function. During their sojourn in the epididymis spermatozoa acquire the capacity to move and to fertilise eggs; they are then stored in a quiescent state prior to ejaculation. The ability of sperm to undergo the events of fertilisation are developed as a result of interactions with certain epididymal secretions. Increases in our knowledge about the genes coding for epididymal secretions has not yet been matched by similar insight into the role that these secretions play in the maturation process. However, information about the changes that occur to the sperm cells during maturation permit certain scenarios to be sketched that may reflect reality. This review is one such attempt to bring the epididymal sperm-epithelial secretion into focus.
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Affiliation(s)
- T G Cooper
- Institute of Reproductive Medicine of the University, Münster, Germany
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