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1.
Rev. Rol enferm ; 45(10): 9-17, Oct. 2022. ilus, mapas, tab, graf
Article in Spanish | IBECS | ID: ibc-211105

ABSTRACT

Actualmente en España estamos ante un cambio progresivo en la pirámide poblacional. La que debería tener forma triangular, está siendo invertida dado el aumento de la esperanza de vida de las personas mayores y las bajas tasas de natalidad del país. Este proceso se denomina “Envejecimiento demográfico” y se acompaña de importantes consecuencias a largo y corto plazo como es el problema de las pensiones.La vejez se trata de una época de cambios, tanto físicos como psicológicos y sociales que confluyen negativamente en una mayor vulnerabilidad a padecer ciertas patologías características de la edad como las enfermedades cerebrovasculares o del corazón. Esto es lo que se conoce como “fragilidad”, una cualidad descriptiva del adulto mayor que se caracteriza por la predisposición del mismo a perder progresivamente su autonomía, convirtiéndose en una persona dependiente de cuidadores para poder llevar a cabo las actividades básicas de la vida diaria. Es por ello, que en numerosas ocasiones acaban ocupando una plaza en las residencias de mayores, las cuales son consideradas ”pequeños hospitales” por disponer de todos los cuidados y atención sanitaria necesaria.Sin embargo, existe un malestar manifiesto entre los profesionales del sector debido a la precariedad a la que se enfrentan. La falta de recursos materiales y los sueldos infravalorados pueden llegar a repercutir en la calidad de la asistencia sanitaria que les prestan a los mayores.Pero en contraposición a los aspectos negativos asociados al envejecimiento, también contiene cuestiones positivas, teniendo en cuenta la amplísima madurez y experiencia con la que se enfrentan y superan las barreras que se les presentan. (AU)


Currently in Spain we are facing a progressive change in the population pyramid. The one that should have a triangular shape, is increasingly inverted given the increase in life expectancy of the elderly and the country’s low birth rates. This process is called “demographic aging” and is accompanied by important consequences in the long and short term, such as the problem of pensions.Old age is associated with a time of changes, both physical and psychologicaland social, which negatively converge in a greater vulnerability to certain pathologies characteristic of age, such as cerebrovascular or heart diseases.This is what is known as “fragility”’, a descriptive quality of the elderly that is characterized by their predisposition to progressively lose their autonomy, becoming a person dependent on caregivers to be able to carry out the basic activities of the daily life. That is why, on numerous occasions, they end up occupying a place in nursing homes, which are considered “small hospitals” because they have all the necessary care and health care. However, there is a clear discomfort among professionals in the sector due to the precariousness they face. The lack of material resources and undervalued salaries can have animpact on the quality of health care provided to the elderly.But in contrast to the negative aspects associated with aging, it also containspositive issues, taking into account the vast maturity and experience with which they face and overcome the barriers that are presented to them. (AU)


Subject(s)
Humans , Demography/trends , Aging/pathology , Life Expectancy , Spain , Homes for the Aged , Frailty
2.
Reproduction ; 161(1): 43-59, 2021 01.
Article in English | MEDLINE | ID: mdl-33112288

ABSTRACT

During mating, males provide not only the spermatozoa to fertilize the oocyte but also other stimuli that are essential for initiating and maintaining the reproductive programme in females. In the mammalian oviduct, mating regulates sperm storage, egg transport, fertilization, early embryonic development, and oestradiol metabolism. However, the main molecules underlying these processes are poorly understood. Using microarray analyses, we identified 58 genes that were either induced or repressed by mating in the endosalpinx at 3 h post-stimulus. RT-qPCR confirmed that mating downregulated the expression of the Oas1h and Prim1 genes and upregulated the expression of the Ceacam1, Chad, Chst10, Slc5a3 and Slc26a4 genes. The functional category 'cell-to-cell signalling and interaction' was over-represented in this gene list. Network modelling identified TNF and all-trans retinoic acid (RA) as upstream regulators of the mating-induced transcriptional response, which was confirmed by intraoviductal injection of TNF or RA in unmated rats. It partially mimicked the transcriptional effect of mating in the rat endosalpinx. Furthermore, mating decreased RA levels in oviductal fluid, and RA-receptor-gamma (RARG) exhibited a nuclear location in oviductal epithelium in both unmated and mated rats, indicating RA-RARG transcriptional activity. In conclusion, the early transcriptional response regulated by mating in the rat endosalpinx is mediated by TNF and RA. These signalling molecules regulate a cohort of genes involved in 'cell-to-cell signalling and interactions' and merit further studies to understand the specific processes activated in the endosalpinx to sustain the events that occur in the mammalian oviduct early after mating.


Subject(s)
Oviducts/metabolism , Sexual Behavior, Animal/physiology , Transcriptome , Tretinoin/metabolism , Tumor Necrosis Factor-alpha/metabolism , Animals , Female , Gene Expression Regulation , Male , Mucous Membrane/metabolism , Rats, Sprague-Dawley , Receptors, Retinoic Acid/metabolism , Retinoic Acid Receptor gamma
3.
Front Microbiol ; 11: 324, 2020.
Article in English | MEDLINE | ID: mdl-32194531

ABSTRACT

An extreme halophilic archaeon, strain SGH1, is a novel microorganism isolated from endolithic microbial communities colonizing halites at Salar Grande, Atacama Desert, in northern Chile. Our study provides structural, biochemical, genomic, and physiological information on this new isolate living at the edge of the physical and chemical extremes at the Atacama Desert. SGH1 is a Gram-negative, red-pigmented, non-motile unicellular coccoid organism. Under the transmission electron microscope, strain SGH1 showed an abundant electro-dense material surrounding electron-lucent globular structures resembling gas vacuoles. Strain SGH1 showed a 16S rRNA gene sequence with a close phylogenetic relationship to the extreme halophilic archaea Haloterrigena turkmenica and Haloterrigena salina and has been denominated Haloterrigena sp. strain SGH1. Strain SGH1 grew at 20-40°C (optimum 37°C), at salinities between 15 and 30% (w/v) NaCl (optimum 25%) and growth was improved by addition of 50 mM KCl and 0.5% w/v casamino acids. Growth was severely restricted at salinities below 15% NaCl and cell lysis is avoided at a minimal 10% NaCl. Maximal concentrations of magnesium chloride and sodium or magnesium perchlorates that supported SGH1 growth were 0.5 and 0.15M, respectively. Haloterrigena sp. strain SGH1 accumulates bacterioruberin (BR), a C50 xanthophyll, as the major carotenoid. Total carotenoids in strain SGH1 amounted to nearly 400 µg BR per gram of dry biomass. Nearly 80% of total carotenoids accumulated as geometric isomers of BR: all-trans-BR (50%), 5-cis-BR (15%), 9-cis-BR (10%), 13-cis-BR (4%); other carotenoids were dehydrated derivatives of BR. Carotenogenesis in SGH1 was a reversible and salt-dependent process; transferring BR-rich cells grown in 25% (w/v) NaCl to 15% (w/v) NaCl medium resulted in depigmentation, and BR content was recovered after transference and growth of unpigmented cells to high salinity medium. Methanol extracts and purified BR isomers showed an 8-9-fold higher antioxidant activity than Trolox or ß-carotene. Both, plasma membrane integrity and mitochondrial membrane potential measurements under acute 18-h assays showed that purified BR isomers were non-toxic to cultured human THP-1 cells.

4.
Mol Hum Reprod ; 25(10): 587-600, 2019 10 28.
Article in English | MEDLINE | ID: mdl-31329238

ABSTRACT

One of the first events of mammalian sperm capacitation is the activation of the soluble adenyl cyclase/cAMP/protein kinase A (SACY/cAMP/PKA) pathway. Here, we evaluated whether the increase in PKA activity at the onset of human sperm capacitation is responsible for the activation of the sperm proteasome and whether this activation is required for capacitation progress. Viable human sperm were incubated with inhibitors of the SACY/cAMP/PKA pathway. The chymotrypsin-like activity of the sperm proteasome was evaluated using a fluorogenic substrate. Sperm capacitation status was evaluated using the chlortetracycline assay and tyrosine phosphorylation. To determine whether proteasomal subunits were phosphorylated by PKA, the proteasome was immunoprecipitated and tested on a western blot using an antibody against phosphorylated PKA substrates. Immunofluorescence microscopy analysis and co-immunoprecipitation (IPP) were used to investigate an association between the catalytic subunit alpha of PKA (PKA-Cα) and the proteasome. The chymotrypsin-like activity of the sperm proteasome significantly increased after 5 min of capacitation (P < 0.001) and remained high for the remaining incubation time. Treatment with H89, KT5720 or KH7 significantly decreased the chymotrypsin-like activity of the proteasome (P < 0.001). IPP experiments indicated that PKA inhibition significantly modified phosphorylation of proteasome subunits. In addition, PKA-Cα colocalized with the proteasome in the equatorial segment and in the connecting piece, and co-immunoprecipitated with the proteasome. This is the first demonstration of sperm proteasome activity being directly regulated by SACY/PKA-Cα. This novel discovery extends our current knowledge of sperm physiology and may be used to manage sperm capacitation during assisted reproductive technology procedures.


Subject(s)
Adenylyl Cyclases/metabolism , Chymotrypsin/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Cyclic AMP/metabolism , Proteasome Endopeptidase Complex/metabolism , Sperm Capacitation , Adult , Enzyme Activation/physiology , Humans , Male , Phosphorylation , Semen Analysis , Signal Transduction/physiology , Young Adult
5.
Mol Reprod Dev ; 83(10): 875-883, 2016 10.
Article in English | MEDLINE | ID: mdl-27371809

ABSTRACT

The oviduct connects the ovary to the uterus, and is subject to changes that influence gamete transport, fertilization, and early embryo development. The ovarian steroids estradiol and progesterone are largely responsible for regulating oviduct function, although mating signals also affect the female reproductive tract, both indirectly, through sensory stimulation, and directly, through contact with seminal plasma or spermatozoa. The resulting alterations in gene and protein expression help establish a microenvironment that is appropriate for sperm storage and selection, embryo development, and gamete transport. Mating may also induce the switch from a non-genomic to a genomic pathway of estradiol-accelerated oviduct egg transport, reflecting a novel example of the functional plasticity in well-differentiated cells. This review highlights the physiological relevance of various aspects of mating to oviduct biology and reproductive success. Expanding our knowledge of the mating-associated molecular and cellular events in oviduct cells would undoubtedly facilitate new therapeutic strategies to treat infertility attributable to oviduct pathologies. Mol. Reprod. Dev. 83: 875-883, 2016 © 2016 Wiley Periodicals, Inc.


Subject(s)
Coitus/physiology , Copulation/physiology , Embryonic Development/physiology , Fertilization/physiology , Ovary/physiology , Oviducts/physiology , Animals , Female , Humans , Male , Semen/metabolism
6.
Mol Reprod Dev ; 81(11): 1053-61, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25359088

ABSTRACT

Mating shuts down a 2-methoxyestradiol (2ME)-dependent, non-genomic activity that is responsible for accelerating egg transport in the rat oviduct. The aims of this work were to investigate the role of TGFß1 in this 2ME-reduced activity and to determine the effect of mating on the expression and distribution of TGFß1 and its receptor TGFBR3 in the rat oviduct. We determined the level of TGFß1 in the plasma and oviductal fluid at 1, 3, or 6 hr during Day 1 of the oestrous cycle in unmated or mated animals. We then examined if 2ME accelerates oviductal egg transport in unmated rats that were previously treated with a neutralizing TGFß1 antibody. The expression of Tgfb1 and Tgfbr3 mRNA and the level and distribution of TGFBR3 protein in the oviduct were also determined at these time points. Mating decreased TGFß1 in the plasma, but not in the oviductal fluid, whereas antibody neutralization of circulating TGFß1 did not prevent the effect of 2ME on egg transport. Mating decreased Tgfb1 and hastened the increase in TGFBR3 abundance in the myosalpinx. These results indicate that mating decreased circulating levels of TGFß1 without shutting down the non-genomic 2ME response that normally accelerates egg transport. Levels of Tgfb1 transcript and TGFBR3 protein, however, changed in the myosalpinx of mated rats, suggesting a role for mating-associated factors in the autocrine and paracrine effects of TGFß in the oviduct.


Subject(s)
Fallopian Tubes/metabolism , Muscle, Smooth/metabolism , Proteoglycans/metabolism , Receptors, Transforming Growth Factor beta/metabolism , Sexual Behavior, Animal/physiology , Transforming Growth Factor beta1/metabolism , 2-Methoxyestradiol , Animals , DNA Primers/genetics , Enzyme-Linked Immunosorbent Assay , Estradiol/analogs & derivatives , Estradiol/metabolism , Estradiol/pharmacology , Female , Fluorescent Antibody Technique , Immunoblotting , Rats , Real-Time Polymerase Chain Reaction , Statistics, Nonparametric , Transforming Growth Factor beta1/blood
7.
Reproduction ; 145(2): 109-17, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23148087

ABSTRACT

Mating shut down a 2-methoxyestradiol (2ME) nongenomic action necessary to accelerate egg transport in the rat oviduct. Herein, we investigated whether tumour necrosis factor-α (TNF-α) participates in this mating effect. In unmated and mated rats, we determined the concentration of TNF-α in the oviductal fluid and the level of the mRNA for Tnf-a (Tnf) and their receptors Tnfrsf1a and Tnfrsf1b in the oviduct tissues. The distribution of the TNFRSF1A and TNFRSF1B proteins in the oviduct of unmated and mated was also assessed. Finally, we examined whether 2ME accelerates oviductal egg transport in unmated rats that were previously treated with a rat recombinant TNF-α alone or concomitant with a selective inhibitor of the NF-κB activity. Mating increased TNF-α in the oviductal fluid, but Tnf transcript was not detected in the oviduct. The mRNA for TNF-α receptors as well as their distribution was not affected by mating, although they were mainly localized in the endosalpinx. Administration of TNF-α into the oviduct of unmated rats prevented the effect of 2ME on egg transport. However, the NF-κB activity inhibitor did not revert this effect of TNF-α. These results indicate that mating increased TNF-α in the oviductal fluid, although this not associated with changes in the expression and localization of TNF-α receptors in the oviductal cells. Furthermore, TNF-α mimicked the effect of mating on the 2ME-induced egg transport acceleration, independently of the activation of NF-κB in the oviduct. We concluded that TNF-α is the signal induced by mating to shut down a 2ME nongenomic action in the rat oviduct.


Subject(s)
Estradiol/analogs & derivatives , Fallopian Tubes/drug effects , Ovum Transport/drug effects , Sexual Behavior, Animal/physiology , Tumor Necrosis Factor-alpha/physiology , 2-Methoxyestradiol , Acceleration , Animals , Body Fluids/chemistry , Body Fluids/metabolism , Estradiol/pharmacology , Fallopian Tubes/metabolism , Female , Genome/drug effects , Ovum Transport/physiology , Rats , Rats, Sprague-Dawley , Signal Transduction/physiology , Tumor Necrosis Factor-alpha/metabolism , Up-Regulation/physiology
8.
Cell Signal ; 23(2): 449-57, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20965247

ABSTRACT

Transforming growth factor ß (TGF-ß) is a very strong pro-fibrotic factor which mediates its action, at least in part, through the expression of connective tissue growth factor (CTGF/CCN2). Along with these cytokines, the involvement of phospholipids in wound healing and the development of fibrosis has been revealed. Among them, lysophosphatidic acid (LPA) is a novel, potent regulator of wound healing and fibrosis that has diverse effects on many types of cells. We decided to evaluate the effect of LPA together with TGF-ß on CTGF expression. We found that myoblasts treated with LPA and TGF-ß1 produced an additive effect on CTGF expression. In the absence of TGF-ß, the induction of CTGF expression by LPA was abolished by a dominant negative form of the TGF-ß receptor type II (TGF-ßRII) and by the use of SB 431542, a specific inhibitor of the serine/threonine kinase activity of TGF-ßRI, suggesting that CTGF induction is dependent on LPA and requires active TGF-ßRs. Moreover, we show that LPA requires Smad-2/3 proteins for the induction of CTGF expression, but not their phosphorylation or their nuclear translocation. The requirement of TGF-ßRI for LPA mediated-effects is differential, since treatment of myoblasts with LPA in the presence of SB 431542 abolished the induction of stress fibers but not the induction of proliferation. Finally, we demonstrated that CTGF induction in response to LPA requires the activation of JNK, but not ERK, signaling pathways. The JNK requirement is independent of TGF-ßRI-mediated activity. These novel results for the mechanism of action of LPA and TGF-ß are important for understanding the role of pro-fibrotic growth factors and phospholipids involved in wound healing and related diseases.


Subject(s)
Connective Tissue Growth Factor/biosynthesis , JNK Mitogen-Activated Protein Kinases/physiology , Lysophospholipids/physiology , Receptors, Transforming Growth Factor beta/metabolism , Animals , Cell Line , Lysophospholipids/pharmacology , Mice , Receptors, Transforming Growth Factor beta/genetics , Signal Transduction , Smad2 Protein/physiology , Smad3 Protein/physiology , Transcriptional Activation
9.
Reprod Biol Endocrinol ; 7: 139, 2009 Nov 30.
Article in English | MEDLINE | ID: mdl-19948032

ABSTRACT

BACKGROUND: Mating changes the mode of action of 17beta-estradiol (E2) to accelerate oviductal egg transport from a nongenomic to a genomic mode, although in both pathways estrogen receptors (ER) are required. This change was designated as intracellular path shifting (IPS). METHODS: Herein, we examined the subcellular distribution of ESR1 and ESR2 (formerly known as ER-alpha and ER-beta) in oviductal epithelial cells of rats on day 1 of cycle (C1) or pregnancy (P1) using immunoelectron microscopy for ESR1 and ESR2. The effect of mating on intraoviductal ESR1 or ESR2 signaling was then explored comparing the expression of E2-target genes c-fos, brain creatine kinase (Ckb) and calbindin 9 kDa (s100g) in rats on C1 or P1 treated with selective agonists for ESR1 (PPT) or ESR2 (DPN). The effect of ER agonists on egg transport was also evaluated on C1 or P1 rats. RESULTS: Receptor immunoreactivity was associated with the nucleus, cytoplasm and plasma membrane of the epithelial cells. Mating affected the subcellular distribution of both receptors as well as the response to E2. In C1 and P1 rats, PPT increased Ckb while both agonists increased c-fos. DPN increased Ckb and s100g only in C1 and P1 rats, respectively. PPT accelerated egg transport in both groups and DPN accelerated egg transport only in C1 rats. CONCLUSION: Estrogen receptors present a subcellular distribution compatible with E2 genomic and nongenomic signaling in the oviductal epithelial cells of C1 and P1 although IPS occurs independently of changes in the distribution of ESR1 and ESR2 in the oviductal epithelial cells. Mating affected intraoviductal ER-signaling and induced loss of functional involvement of ESR2 on E2-induced accelerated egg transport. These findings reveal a profound influence on the ER signaling pathways exerted by mating in the oviduct.


Subject(s)
Fallopian Tubes/metabolism , Receptors, Estrogen/metabolism , Receptors, Estrogen/physiology , Sexual Behavior, Animal/physiology , Animals , Calbindins , Creatine Kinase, BB Form/metabolism , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Estrous Cycle/genetics , Estrous Cycle/metabolism , Fallopian Tubes/drug effects , Fallopian Tubes/physiology , Female , Ginsenosides/pharmacology , Nitriles/pharmacology , Oocytes/drug effects , Oocytes/metabolism , Pregnancy , Proto-Oncogene Proteins c-fos/metabolism , Rats , Rats, Sprague-Dawley , Receptors, Estrogen/agonists , Receptors, Estrogen/genetics , S100 Calcium Binding Protein G/metabolism , Sapogenins/pharmacology , Tissue Distribution
10.
J Cell Physiol ; 215(2): 410-21, 2008 May.
Article in English | MEDLINE | ID: mdl-18064627

ABSTRACT

Fibrotic disorders are typified by excessive connective tissue and extracellular matrix (ECM) deposition that precludes normal healing processes of different tissues. Connective tissue growth factor (CTGF) seems to be involved in the fibrotic response. Several muscular dystrophies are characterized by a progressive weakness and wasting of the musculature, and by extensive fibrosis. However, the exact role of CTGF in skeletal muscle is unknown. Here we show that myoblasts and myotubes are able to synthesize CTGF in response to transforming growth factor type-beta (TGF-beta) and lysophosphatidic acid (LPA). CTGF induced several ECM constituents such as fibronectin, collagen type I and alpha4, 5, 6, and beta1 integrin subunits in myoblasts and myotubes. CTGF had an important inhibitory effect on muscle differentiation evaluated by the decrease in the nuclear translocation of the early muscle regulatory factor myogenin and myosin. Remarkable, CTGF treatment of myoblasts induced their dedifferentiation, characterized by down regulating MyoD and desmin, two markers of committed myoblasts, together with a strong reorganization of cytoskeletal filaments. These results provide novel evidence for the underlying mechanisms and participation of skeletal muscle cells in the synthesis and role of CTGF inducing fibrosis, inhibiting myogenesis and dedifferentiating myoblasts.


Subject(s)
Cell Dedifferentiation , Immediate-Early Proteins/metabolism , Intercellular Signaling Peptides and Proteins/metabolism , Muscle, Skeletal/cytology , Muscle, Skeletal/metabolism , Animals , Biological Transport/drug effects , Cell Differentiation/drug effects , Cell Line , Cell Nucleus/metabolism , Connective Tissue Growth Factor , Cytoskeleton/drug effects , Desmin/metabolism , Down-Regulation , Extracellular Matrix Proteins/biosynthesis , Immediate-Early Proteins/biosynthesis , Immediate-Early Proteins/pharmacology , Intercellular Signaling Peptides and Proteins/biosynthesis , Intercellular Signaling Peptides and Proteins/pharmacology , Lysophospholipids/pharmacology , Mice , Muscle Fibers, Skeletal/drug effects , Muscle Fibers, Skeletal/metabolism , Muscle, Skeletal/drug effects , MyoD Protein/metabolism , Myoblasts/cytology , Myoblasts/drug effects , Myoblasts/metabolism , Myogenin/metabolism , Myosins/metabolism , Recombinant Proteins/pharmacology , Transforming Growth Factor beta/pharmacology
11.
J Endocrinol ; 188(3): 579-88, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16522737

ABSTRACT

Oestradiol (E(2)) accelerates oviductal transport of oocytes in cycling rats through a nongenomic pathway that involves the cAMP-PKA signalling cascade. Here we examined the role of the inositol triphosphate (IP3) and mitogen-activated protein kinase (MAPK) signalling cascades in this nongenomic pathway. Oestrous rats were injected with E(2) s.c. and intrabursally (i.b) with the selective inhibitors of phospholipase C (PLC) ET-18-OCH(3) or MAPK PD98059. The number of eggs in the oviduct assessed 24 h later showed that ET-18-OCH(3) blocked E(2)-induced egg transport acceleration, whereas PD98059 had no effect. Other oestrous rats were treated with E(2) s.c. and 1, 3 or 6 h later oviducts were excised and the levels of IP3 and phosphorylated MAPK p44/42 (activated) were determined by radioreceptor assay and western blot, respectively. Oestradiol administration increased IP3 level at 1 and 6 h after treatment, whereas activated MAPK p44/42 level was unchanged. Finally, we explored whether cAMP-PKA and PLC-IP3 signalling cascades are coupled. Inhibition of adenylyl cyclase by i.b. injection of SQ 22536 blocked the increase of IP3 levels induced by E(2), while inhibition of PLC by ET-18-OCH(3) had no effect on E(2)-induced PKA activity. Furthermore, activation of adenylyl cyclase by Forskolin increased oviductal IP3 levels. Thus, activation of PLC-IP3 by E(2) requires previous stimulation of cAMP-PKA. We conclude that the nongenomic pathway utilised by E(2) to accelerate oviductal transport of oocytes in cycling rats involves successive activation of the cAMP-PKA and PLC-IP3 signalling cascades and does not require activation of MAPK. These findings clearly illustrate a non-genomic pathway triggered by E(2) that regulates a complex physiologic process accomplished by an entire organ.


Subject(s)
Estradiol/pharmacology , Fallopian Tubes/metabolism , Inositol Phosphates/physiology , Mitogen-Activated Protein Kinase Kinases/metabolism , Ovum Transport/physiology , Signal Transduction/physiology , Adenine/analogs & derivatives , Adenine/pharmacology , Adenylyl Cyclase Inhibitors , Adenylyl Cyclases/metabolism , Animals , Colforsin/pharmacology , Cyclic AMP/metabolism , Cyclic AMP-Dependent Protein Kinases/antagonists & inhibitors , Cyclic AMP-Dependent Protein Kinases/metabolism , Enzyme Inhibitors/pharmacology , Estrus , Female , Flavonoids/pharmacology , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/physiology , Mitogen-Activated Protein Kinase Kinases/antagonists & inhibitors , Oocytes/cytology , Oocytes/drug effects , Phosphatidylcholines/pharmacology , Phospholipid Ethers , Rats , Rats, Sprague-Dawley , Type C Phospholipases/antagonists & inhibitors , Type C Phospholipases/metabolism
12.
Biol Reprod ; 71(4): 1262-9, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15201197

ABSTRACT

The aim of this study was to assess the participation of carbohydrate residues in the adhesion of spermatozoa to the oviductal epithelium in the rat. We first examined, by lectin labeling, the distribution of glycoconjugates in rat oviducts obtained under various hormonal environments. Several classes of glycoconjugates were abundant in the epithelium, and the expression of some of these molecules varied differentially in ampulla and isthmus, along the estrous cycle and with estradiol and progesterone treatment. Proestrous rats were intraoviductally injected with lectins Dolichos biflorus, Erythrina cristagalli, Helix pomatia, Arachis hypogea, Ulex europaeus I, Triticum vulgaris, or Tritrichomonas mobilensis and were inseminated with 10-20 million epididymal spermatozoa in each uterine horn. Three hours later, the total number of spermatozoa present in the oviduct and the proportion adhering to the epithelium were determined. Intraoviductal administration of lectins did not affect the total number of spermatozoa recovered from the oviduct and only the sialic acid-binding lectin TML decreased the percentage of sperm cells adhering to the epithelium. The involvement of sialic acid in sperm-oviduct adhesion was further explored, inseminating spermatozoa preincubated with mannose, galactose, sialic acid, fucose, fetuin, or asialofetuin. Sialic acid and fetuin inhibited sperm-oviduct binding while other carbohydrates had no effect. Using TML lectin immunohistochemistry, we found that sialic acid-rich glycoconjugates are equally localized in the epithelium of ampulla and isthmus of proestrous rats. The electrophoretic pattern of sialic acid-rich glycoproteins of the epithelium showed 15 major protein bands, for which molecular mass ranged from 200 to 50 kDa with no difference between ampulla and isthmus or between estrous cycle stages. Binding sites for sialic acid-fluorescein isothiocyanate were demonstrated on the surface of rat spermatozoa, and biotinylated sialic acid recognized 11 plasma membrane proteins of sperm cells. These groups of sialic acid-rich glycoproteins in the oviductal epithelium and of sialic acid-binding proteins in the plasma membrane of sperm cells are good candidates for further studies to characterize the molecules responsible for sperm binding. We conclude that there are segment-specific changes of sugar residues present in the oviductal epithelium associated with different endocrine environments. Sperm-oviduct adhesion in the rat occurs by interaction of sialoglycoconjugates present in the epithelial cells with sialic acid-binding proteins on the sperm surface. This replicates the situation previously found in hamsters, disclosing for the first time that species-specificity in the sugar involved in sperm binding is not absolute.


Subject(s)
Epithelial Cells/metabolism , Fallopian Tubes/metabolism , Glycoconjugates/metabolism , N-Acetylneuraminic Acid/metabolism , Spermatozoa/metabolism , Animals , Binding Sites , Cell Adhesion/physiology , Cell Membrane/metabolism , Fallopian Tubes/cytology , Female , Ligands , Male , Membrane Proteins/metabolism , Rats , Sperm Maturation/physiology , Tissue Distribution
13.
Reprod Toxicol ; 17(6): 667-72, 2003.
Article in English | MEDLINE | ID: mdl-14613818

ABSTRACT

This work was undertaken to examine possible embryotoxicity of Ruta graveolens (rue), a plant used by indigenous communities for the purposes of therapeutic and fertility regulation. Superovulated mice were mated and isolated after copulation. They were given aqueous extract of R. graveolens (5, 10, and 20% w/v) or plain water (control) orally for 4 days. Ninety-eight hours post-human chorionic gonadotrophin (hCG), embryos were flushed from oviducts and uterine horns to assess their state of development and extent of embryo transport. Ingestion of rue at 10 and 20% resulted in a high proportion of abnormal embryos (36.7 and 63.6%, respectively, P<0.05). Cell number was diminished (P<0.01) and embryo transport was slightly delayed in the highest dose group. These findings demonstrate that oral administration of R. graveolens extract can interfere with preimplantation development and embryo transport.


Subject(s)
Blastocyst/drug effects , Ruta/chemistry , Animals , Body Weight/drug effects , Cell Count , Dose-Response Relationship, Drug , Embryonic and Fetal Development/drug effects , Female , Injections, Intraperitoneal , Mice , Morula/drug effects , Plant Extracts/pharmacology , Pregnancy
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