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Louis Hermo - One of the best experts on this subject based on the ideXlab platform.
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cell and region specific localization of lysosomal and secretory proteins and endocytic receptors in epithelial cells of the Cauda Epididymidis and vas deferens of the adult rat
Journal of Andrology, 1999Co-Authors: Sero Andonian, Louis HermoAbstract:The epithelial cells lining the Cauda Epididymidis and vas deferens are active in endocytosis and have an abundance of lysosomes and a well-characterized secretory apparatus. However, little is known about the nature of lysosomal proteins contained within lysosomes, the types of receptors on the cell surface, and the types of proteins secreted by these cells. In the present study, cathepsins A, D, B, and sulfated glycoprotein (SGP)-1, well-characterized lysosomal proteins, as well as SGP-2, a secretory protein and low-density lipoprotein receptor-related protein-2 (LRP-2), an endocytic receptor, were immunolocalized at the light-microscopic level within epithelial cells of the Cauda Epididymidis and vas deferens. Principal cells showed numerous intensely reactive lysosomes for cathepsins A, D, and SGP-1 in all regions of the Cauda and vas deferens and for cathepsin B only in the Cauda Epididymidis. Basal cells were intensely reactive for cathepsin A, unreactive for cathepsins D and B, and weakly reactive for SGP-1 in the Cauda region. In the vas deferens, these cells were intensely reactive for cathepsin A and SGP-1 and unreactive for cathepsin B; in the case of cathepsin D, basal cells were weakly reactive in the proximal vas deferens but intensely reactive in the middle and distal vas deferens. Clear cells, present in the Cauda region and proximal vas deferens, were intensely reactive for cathepsin A, weakly reactive for SGP-1, and unreactive for cathepsins D and B, while narrow cells found mainly in the proximal vas deferens were intensely reactive for cathepsins A, D, and SGP-1 and unreactive for cathepsin B. Thus, the expression of different lysosomal enzymes in the Cauda Epididymidis and vas deferens is not only cell- but also region-specific, suggesting differences in the type of substrates internalized by these cells. SGP-2, a secretory protein, showed a checkerboardlike staining pattern in the cytoplasm of principal cells of the Cauda Epididymidis, while the cytoplasm of all principal cells were intensely reactive in the vas deferens. This type of reaction, as well as staining of sperm, suggests that SGP-2 is secreted into the lumen, where it functions in relation to sperm. The endocytic receptor LRP-2 was noted only on the apical surface of principal cells of the Cauda and vas deferens and in spherical structures indicative of endosomes suggestive of their role in the uptake of various ligands, including SGP-2, for which it has a high binding affinity. Thus SGP-2 in the Cauda and vas deferens is not only secreted but endocytosed by principal cells, suggestive of an active turnover in the lumen. In summary, the epithelial cells of the Cauda and vas deferens show marked differences in expression of lysosomal proteins, SGP-2, and LRP-2 suggestive of differences in their functional activity while sperm are stored and protected in these regions.
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immunocytochemical localization of the ya yb1 yc yf and yo subunits of glutathione s transferases in the Cauda Epididymidis and vas deferens of adult rats
Journal of Andrology, 1999Co-Authors: Sero Andonian, Louis HermoAbstract:Glutathione S-transferases (GSTs) are dimeric proteins grouped into five classes based on the degree of amino acid homology of their subunits. They are involved in cellular detoxification through the catalyzation of the conjugation of reduced glutathione with various electrophilic substances. In the present study, the distribution of Ya and Yc subunits from the alpha family, Yb1 and Yo subunits of the mu class, and the Yf subunit of the pi class were examined with light microscope immunocytochemistry in Bouin-fixed, paraffin-embedded tissue of different regions of the Cauda Epididymidis and vas deferens. In the Cauda, principal cells showed high levels of expression of Ya, Yc, and Yo subunits, while in the vas deferens, staining decreased to moderate levels for the Ya and Yo subunits and to low levels for the Yc subunit. While Yf was maintained at low levels in principal cells of all Cauda and vas deferens regions, Yb1 expression was more erratic, presenting a checkerboard-like staining pattern in the proximal vas deferens and showing moderate cytoplasmic but intense nuclear reactivity in all other regions. Basal cells in the Cauda were intensely reactive for Yf, while in the vas deferens, they became unreactive. Conversely, basal cells were unreactive for Ya in the Cauda and proximal vas deferens, while in the middle and distal vas deferens, they became moderately reactive. In the case of Yb1 and Yo, some basal cells were reactive while others appeared unreactive in all Cauda and vas deferens regions. Yc elicited the display of both reactive and unreactive basal cells in the Cauda regions, and while the cells were moderately reactive in the proximal vas deferens, they became intensely reactive in the middle and distal vas deferens. In summary, both principal and basal cells show varying degrees of GST expression in the different regions of the Cauda and vas deferens, suggesting that these cells are subjected to a complex, changing environment of substrates. Furthermore, while expression often differs from principal to basal cells, the absence of reactivity of a given GST in one cell type is usually compensated for by expression in the other cell type in any given region of the Cauda or vas deferens. Taken together, the data suggest that ample protection from harmful circulating electrophiles can be provided for sperm during their storage in the Cauda and vas deferens. In addition, since principal cells of the vas deferens are involved in steroid synthesis, the presence of GSTs in these cells may also serve to bind steroids, or this presence may be involved in steroid isomerization.
R J Aitken - One of the best experts on this subject based on the ideXlab platform.
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Adenylyl cyclase isoforms in rat testis and spermatozoa from the Cauda Epididymidis
Cell and Tissue Research, 2003Co-Authors: M A Wade, R C Jones, S. D. Roman, R J AitkenAbstract:Expression of adenylyl cyclase genes in rat testis and spermatozoa from the Cauda Epididymidis was investigated using RT-PCR analysis. Genes encoding the transmembrane adenylyl cyclases (tmAC) II, III, IV, V, VI, VII, and VIII were expressed in the testis, whereas only the gene for tmAC III was expressed in Caudal spermatozoa. Immunocytochemistry was used to investigate which tmAC were translated into putative, functional proteins in spermatozoa. Indirect immunofluorescence localized the tmAC II enzyme to a region on the head occupied by the acrosome. The tmAC III enzyme was localized to the posterior margin of the head and to the flagellum, whereas tmAC V and/or VI was localized to the region where the ventral surface of the acrosomal equatorial segment is located. The tmAC VII and VIII enzymes were localized to the convex margin of the head, covering the dorsal region of the acrosomal crescent. To our knowledge, this is the first demonstration that five apparently different tmAC enzymes are localized to discrete subcellular regions of mammalian spermatozoa. These findings provide a fundamental basis for future studies, to determine the physiological roles of tmAC in testis and mature spermatozoa.
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motility activation and second messenger signalling in spermatozoa from rat Cauda Epididymidis
Reproduction, 2003Co-Authors: M A Wade, R C Jones, R N Murdoch, R J AitkenAbstract:This study examined molecular mechanisms involved in the activation of motility in spermatozoa from the Cauda Epididymidis of rats. A 1.05-fold dilution of semen from the Cauda Epididymidis with 300 mmol sucrose I -1 did not activate motility in spermatozoa. Addition of dibutyryl cAMP, pentoxifylline or Ca 2+ to the sucrose activated motility in the short term (< 30-60 min). A fivefold dilution of semen from the Cauda Epididymidis with a modified Tyrode's medium (BWW) activated and sustained vigorous motility that could not be attenuated with kinase inhibitors. This motility was associated with a transient increase in intracellular cAMP during the first 60s of activation. Lower motility was activated in Ca 2+ -deficient media but this was not associated with an increase in cAMP. A fivefold dilution with plasma from the Cauda Epididymidis did not activate motility. The addition of Ca 2+ to the sucrose induced an increase in cAMP of similar duration but lower magnitude to that associated with dilution in BWW. The results from this study indicate that the cAMP and Ca 2+ signal transduction pathways are involved in activation of sperm motility, and that the increase in intracellular cAMP in rat spermatozoa from the Cauda Epididymidis undergoing motility activation is Ca 2+ -dependent. This is the first study to report a Ca 2+ -dependent increase in cAMP associated with motility activation in immotile mammalian spermatozoa. In light of these data, a model is proposed whereby cAMP and Ca 2+ act as synarchic messengers, initiating a signal transduction cascade, which is independent of protein kinase A-mediated phosphorylation of flagella proteins in immotile spermatozoa from the Cauda Epididymidis.
Bernard Robaire - One of the best experts on this subject based on the ideXlab platform.
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1 Null Mutation of the Transcription Factor Inhibitor of DNA Binding 3 (Id3) Affects Spermatozoal Motility Parameters and Epididymal Gene Expression in Mice
2016Co-Authors: Epididymal Id-deficient, Michelle Carroll, Trang Luu, Bernard RobaireAbstract:Summary sentence: Transcription factor expression in the Cauda Epididymidis is significantly altered in animals bearing a null mutation of the Id3 gene
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effects of ageing on spermatozoal chromatin and its sensitivity to in vivo and in vitro oxidative challenge in the brown norway rat
Human Reproduction, 2006Co-Authors: Ekaterina V Zubkova, Bernard RobaireAbstract:BACKGROUND: The goals of our study were to examine chromatin packaging and integrity in spermatozoa taken from the caput and Cauda epididymides of young (4-month-old) and old (21-month-old) Brown Norway rats and to assess whether spermatozoal sensitivity to oxidative treatments is altered with age. METHODS: Oxidative treatments consisted of (i) in vivo oxidative challenge by systemic administration of the glutathione-depleting drug L-buthionine-[S,R]-sulphoximine (BSO) and (ii) in vitro oxidative challenge by incubating collected spermatozoa with hydrogen peroxide (H 2 O 2 ). Chromatin parameters assessed included quantification of thiols, nuclear chromomycin A3 (CMA3) penetration, DNA breaks by TdT (terminal deoxynucleotidyl transferase)-mediated dUDP nick-end labelling (TUNEL) and ease of DNA dissociation by acridine orange (AO) staining. RESULTS: In spermatozoa from older rats, we found decreases in thiols, CMA3 penetration and the percentage of cells that undergo DNA dissociation. Administration of BSO had oxidizing effects on the thiol groups. It also decreased CMA3 penetration and DNA dissociation and increased TUNEL staining. Furthermore, BSO treatment sensitized Cauda Epididymidis spermatozoa, from older animals, to H 2 O 2 . CONCLUSIONS: Overall, we show that spermatozoa from older rats have altered chromatin packaging and integrity and that spermatozoa from the Cauda Epididymidis are more responsive to combined in vivo and in vitro oxidative challenge than spermatozoa from young rats.
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effect of glutathione depletion on antioxidant enzymes in the epididymis seminal vesicles and liver and on spermatozoa motility in the aging brown norway rat
Biology of Reproduction, 2004Co-Authors: Ekaterina V Zubkova, Bernard RobaireAbstract:Reactive oxygen species (ROS) play a role in male infertility, where excessive amounts impair spermatozoal motility. Epididymal antioxidant enzymes protect spermatozoa from oxidative damage in the epididymal lumen. Antioxidant secretions from the seminal vesicle protect spermatozoa after ejaculation. As it is known that with age there is increased generation of ROS, the goals of this study were to determine how aging affects the response of antioxidant enzymes in the epididymis, seminal vesicles, and liver to L-buthionine-S,R-sulfoximine (BSO) mediated glutathione (GSH) depletion, and to examine the impact of GSH depletion on motility parameters of spermatozoa from the Cauda Epididymidis in young (4-mo-old) and old (21-mo-old) rats. Levels of GSH and glutathione disulfide (GSSG), as well as activities of glutathione peroxidase, glutathione reductase, catalase, and superoxide dismutase, were measured in the caput, corpus and Cauda Epididymidis, seminal vesicles, and liver. Spermatozoal motility was assessed by computer-assisted sperm analysis. Significant age-related changes in antioxidant enzyme activities were found in the liver and Cauda Epididymidis. Glutathione depletion clearly affected tissues in both young and old. The compounding effect of age was most evident in the Cauda Epididymidis, seminal vesicles, and liver, where antioxidant enzyme activities changed significantly. Additionally, spermatozoa motility was adversely affected after BSO treatment in both age groups, but significantly more so in older animals. In summary, the male reproductive tissues and liver undergo age-related changes in antioxidant enzyme activities and in their response to GSH depletion. aging, epididymis, seminal vesicles, sperm, stress
Sero Andonian - One of the best experts on this subject based on the ideXlab platform.
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cell and region specific localization of lysosomal and secretory proteins and endocytic receptors in epithelial cells of the Cauda Epididymidis and vas deferens of the adult rat
Journal of Andrology, 1999Co-Authors: Sero Andonian, Louis HermoAbstract:The epithelial cells lining the Cauda Epididymidis and vas deferens are active in endocytosis and have an abundance of lysosomes and a well-characterized secretory apparatus. However, little is known about the nature of lysosomal proteins contained within lysosomes, the types of receptors on the cell surface, and the types of proteins secreted by these cells. In the present study, cathepsins A, D, B, and sulfated glycoprotein (SGP)-1, well-characterized lysosomal proteins, as well as SGP-2, a secretory protein and low-density lipoprotein receptor-related protein-2 (LRP-2), an endocytic receptor, were immunolocalized at the light-microscopic level within epithelial cells of the Cauda Epididymidis and vas deferens. Principal cells showed numerous intensely reactive lysosomes for cathepsins A, D, and SGP-1 in all regions of the Cauda and vas deferens and for cathepsin B only in the Cauda Epididymidis. Basal cells were intensely reactive for cathepsin A, unreactive for cathepsins D and B, and weakly reactive for SGP-1 in the Cauda region. In the vas deferens, these cells were intensely reactive for cathepsin A and SGP-1 and unreactive for cathepsin B; in the case of cathepsin D, basal cells were weakly reactive in the proximal vas deferens but intensely reactive in the middle and distal vas deferens. Clear cells, present in the Cauda region and proximal vas deferens, were intensely reactive for cathepsin A, weakly reactive for SGP-1, and unreactive for cathepsins D and B, while narrow cells found mainly in the proximal vas deferens were intensely reactive for cathepsins A, D, and SGP-1 and unreactive for cathepsin B. Thus, the expression of different lysosomal enzymes in the Cauda Epididymidis and vas deferens is not only cell- but also region-specific, suggesting differences in the type of substrates internalized by these cells. SGP-2, a secretory protein, showed a checkerboardlike staining pattern in the cytoplasm of principal cells of the Cauda Epididymidis, while the cytoplasm of all principal cells were intensely reactive in the vas deferens. This type of reaction, as well as staining of sperm, suggests that SGP-2 is secreted into the lumen, where it functions in relation to sperm. The endocytic receptor LRP-2 was noted only on the apical surface of principal cells of the Cauda and vas deferens and in spherical structures indicative of endosomes suggestive of their role in the uptake of various ligands, including SGP-2, for which it has a high binding affinity. Thus SGP-2 in the Cauda and vas deferens is not only secreted but endocytosed by principal cells, suggestive of an active turnover in the lumen. In summary, the epithelial cells of the Cauda and vas deferens show marked differences in expression of lysosomal proteins, SGP-2, and LRP-2 suggestive of differences in their functional activity while sperm are stored and protected in these regions.
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immunocytochemical localization of the ya yb1 yc yf and yo subunits of glutathione s transferases in the Cauda Epididymidis and vas deferens of adult rats
Journal of Andrology, 1999Co-Authors: Sero Andonian, Louis HermoAbstract:Glutathione S-transferases (GSTs) are dimeric proteins grouped into five classes based on the degree of amino acid homology of their subunits. They are involved in cellular detoxification through the catalyzation of the conjugation of reduced glutathione with various electrophilic substances. In the present study, the distribution of Ya and Yc subunits from the alpha family, Yb1 and Yo subunits of the mu class, and the Yf subunit of the pi class were examined with light microscope immunocytochemistry in Bouin-fixed, paraffin-embedded tissue of different regions of the Cauda Epididymidis and vas deferens. In the Cauda, principal cells showed high levels of expression of Ya, Yc, and Yo subunits, while in the vas deferens, staining decreased to moderate levels for the Ya and Yo subunits and to low levels for the Yc subunit. While Yf was maintained at low levels in principal cells of all Cauda and vas deferens regions, Yb1 expression was more erratic, presenting a checkerboard-like staining pattern in the proximal vas deferens and showing moderate cytoplasmic but intense nuclear reactivity in all other regions. Basal cells in the Cauda were intensely reactive for Yf, while in the vas deferens, they became unreactive. Conversely, basal cells were unreactive for Ya in the Cauda and proximal vas deferens, while in the middle and distal vas deferens, they became moderately reactive. In the case of Yb1 and Yo, some basal cells were reactive while others appeared unreactive in all Cauda and vas deferens regions. Yc elicited the display of both reactive and unreactive basal cells in the Cauda regions, and while the cells were moderately reactive in the proximal vas deferens, they became intensely reactive in the middle and distal vas deferens. In summary, both principal and basal cells show varying degrees of GST expression in the different regions of the Cauda and vas deferens, suggesting that these cells are subjected to a complex, changing environment of substrates. Furthermore, while expression often differs from principal to basal cells, the absence of reactivity of a given GST in one cell type is usually compensated for by expression in the other cell type in any given region of the Cauda or vas deferens. Taken together, the data suggest that ample protection from harmful circulating electrophiles can be provided for sperm during their storage in the Cauda and vas deferens. In addition, since principal cells of the vas deferens are involved in steroid synthesis, the presence of GSTs in these cells may also serve to bind steroids, or this presence may be involved in steroid isomerization.
Rosa Carballada - One of the best experts on this subject based on the ideXlab platform.
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Abdominal Temperature Induces Region-Specific p53-Independent Apoptosis in the Cauda Epididymidis of the Mouse1
2016Co-Authors: Marco Jara, Pedro Esponda, Rosa CarballadaAbstract:It is widely accepted that temperature regulates gene ex-pression and function in the epididymis. However, the signifi-cance of reduced temperature of the scrotum in cell survival had not often been examined. Our hypothesis was that the ex-perimental increase of the temperature could induce apoptosis. Using a surgical method that consists of surgically reflecting the Cauda Epididymidis in the abdomen, we have been able to show that this is the case. Apoptosis was examined by histologic pro-cedures and by visualization of DNA fragmentation in agarose gels. We determined that the apoptosis is region-specific and affects only the principal cells of the proximal region of the Cauda. It starts 12 h after surgery and ends by the third day. The apoptotic cells are eliminated by extrusion into the lumen and phagocytosis by adjacent cells. The complete molecular mech-anism of apoptosis in this case remains unknown, but we have used the techniques of immunocytochemistry, Western blot, and reverse transcription-polymerase chain reaction to determine the role of some molecules. We have seen no significant role of androgens, the tumor suppressor p53, nor two heat shock pro-teins, hsp-25 and hsp-70. Nevertheless, we have detected a strong induction of bax and bcl-2 gene products. While the for-mer should be responsible for the apoptosis observed, the latter would promote the survival of most of the cells of the Cauda epididymis. androgen receptor, apoptosis, epididymis, male reproductive tract, male sexual functio
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abdominal temperature induces region specific p53 independent apoptosis in the Cauda Epididymidis of the mouse
Biology of Reproduction, 2002Co-Authors: Marco Jara, Pedro Esponda, Rosa CarballadaAbstract:It is widely accepted that temperature regulates gene expression and function in the epididymis. However, the significance of reduced temperature of the scrotum in cell survival had not often been examined. Our hypothesis was that the experimental increase of the temperature could induce apoptosis. Using a surgical method that consists of surgically reflecting the Cauda Epididymidis in the abdomen, we have been able to show that this is the case. Apoptosis was examined by histologic procedures and by visualization of DNA fragmentation in agarose gels. We determined that the apoptosis is region-specific and affects only the principal cells of the proximal region of the Cauda. It starts 12 h after surgery and ends by the third day. The apoptotic cells are eliminated by extrusion into the lumen and phagocytosis by adjacent cells. The complete molecular mechanism of apoptosis in this case remains unknown, but we have used the techniques of immunocytochemistry, Western blot, and reverse transcription-polymerase chain reaction to determine the role of some molecules. We have seen no significant role of androgens, the tumor suppressor p53, nor two heat shock proteins, hsp-25 and hsp-70. Nevertheless, we have detected a strong induction of bax and bcl-2 gene products. While the former should be responsible for the apoptosis observed, the latter would promote the survival of most of the cells of the Cauda epididymis.