Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 14 de 14
Filter
Add more filters










Publication year range
1.
Nutrients ; 14(6)2022 Mar 16.
Article in English | MEDLINE | ID: mdl-35334913

ABSTRACT

Caloric restriction (CR) has been shown to be an effective nutritional intervention for increasing longevity in some animal species. The objective of this study was to evaluate CR's effects on metabolic and reproductive parameters in 12-month-old male Wistar rats. The rats were distributed in three groups: control, CR at 15%, and CR at 35% for 6 (up to 18 months of age) and 12 months (up to 24 months of age). At the end of CR treatment, we evaluated reproductive (male sexual behavior (MSB), sperm quality) and biochemical parameters (plasma glucose, glucose-regulating hormone, and sex steroid levels), and quantified annexin V in the seminiferous epithelium. Results showed that MSB and sperm quality were improved after 6 months of CR associated with increases in plasma testosterone and decrease annexin V in the seminiferous epithelium of the testicles compared to their control group. The metabolic profile of the CR rats also improved compared to controls. However, these effects of CR on reproductive parameters were not maintained after 12 months of CR. Findings suggest that beginning CR at the age of maturity reestablishes the behavioral sexual response and reproductive function in older animals after 6 months of CR and improves endocrine functioning during aging.


Subject(s)
Caloric Restriction , Longevity , Aging/physiology , Animals , Male , Rats , Rats, Wistar , Testosterone
2.
PeerJ ; 9: e12051, 2021.
Article in English | MEDLINE | ID: mdl-34616602

ABSTRACT

BACKGROUND: Direct Acting Antivirals (DAAs) represent a large improvement in the treatment of chronic hepatitis C, resulting in <90% sustained virological response (SVR). There are no reports on the real-world DAA response for Mexico and few reports exist for Latin America. The aim of the study was to report SVR, and immediate benefits with the DAA treatments sofosbuvir, ledispavir, with/without ribavirin (SOF/LDV ± RBV) and ombitasvir, paritaprevir, ritonavir, dasabuvir with/without RBV (OBV/PTV/r/DSV ± RBV) in patients with viral genotype 1a or 1b, and who did not respond to previous peginterferon/ribavirin (PegIFNα2a+RBV) therapy. METHODS: A descriptive, ambispective, longitudinal study was conducted. A cohort of 261 adult patients received PegIFNα2a+RBV therapy before 2014; 167 (64%) did not respond, 83 of these were subsequently treated with SOF/LDV ± RBV or OBV/PTV/r/DSV ± RBV. Child-Pugh-Score (CPS), Fibrosis-4 (FIB-4), and AST to Platelet Ratio Index (APRI) were evaluated before and after treatment. RESULTS: SVR with PegIFNα2a+RBV was 36%, and 97.5% with DAAs. CPS, FIB-4 and APRI improved significantly after DAA treatment, mainly because of liver transaminase reduction. CONCLUSIONS: DAA treatment showed excellent SVR rates in Mexican patients who had not responded to PegIFNα2a+RBV therapy. Improvement in CPS, FIB-4 and APRI without improvement in fibrosis was observed in cirrhotic and non-cirrhotic patients, as well as considerable reduction in liver transaminases, which suggests a reduction in hepatic necroinflammation.

3.
J Ethnopharmacol ; 248: 112321, 2020 Feb 10.
Article in English | MEDLINE | ID: mdl-31655146

ABSTRACT

ETHNOPHARMACOLOGY RELEVANCE: In traditional Mexican medicine, Echeveria gibbiflora DC has been used as a vaginal post-coital rinse to prevent pregnancy. The aqueous crude extract (OBACE) induces sperm immobilization/agglutination and a hypotonic-like effect, likely attributed to the high concentration of calcium bis-(hydrogen-1-malate) hexahydrate [Ca2+ (C4H5O5)2•6H2O]. Likewise, OBACE impedes the increase of [Ca2+]i during capacitation. AIM OF THE STUDY: Evaluate the effect of OBACE on sperm energy metabolism and the underlying mechanism of action on sperm-specific channel. MATERIAL AND METHODS: In vitro, we quantified the mouse sperm immobilization effect and the antifertility potential of OBACE. The energetic metabolism status was also evaluated by assessing the ATP levels, general mitochondrial activity, mitochondrial membrane potential, and enzymatic activity of three key enzymes of energy metabolism. Furthermore, the effect of the ion efflux of Cl- and K+, as well as the pHi, were investigated in order to elucidate which channel is suitable to perform an in silico study. RESULTS: Total and progressive motility notably decreased, as did fertility rates. ATP levels, mitochondrial activity and membrane potential were reduced. Furthermore, the activities of the three enzymes decreased. Neither Cl- or K+ channels activities were affected at low concentrations of OBACE; nevertheless, pHi did not alkalinize. Finally, an in silico analysis was performed between the Catsper channel and calcium bis-(hydrogen-1-malate) hexahydrate, which showed a possible blockade of this sperm cation channel. CONCLUSION: The results were useful to elucidate the effect of OBACE and to propose it as a future male contraceptive.


Subject(s)
Calcium Channel Blockers/pharmacology , Calcium Channels/drug effects , Calcium Signaling/drug effects , Contraceptive Agents, Male/pharmacology , Crassulaceae , Energy Metabolism/drug effects , Plant Extracts/pharmacology , Spermatozoa/drug effects , Animals , Binding Sites , Calcium Channel Blockers/chemistry , Calcium Channel Blockers/isolation & purification , Calcium Channels/chemistry , Calcium Channels/metabolism , Contraceptive Agents, Male/chemistry , Contraceptive Agents, Male/isolation & purification , Crassulaceae/chemistry , Fertility/drug effects , Hydrogen-Ion Concentration , Male , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Molecular Docking Simulation , Plant Extracts/isolation & purification , Protein Conformation , Sperm Motility/drug effects , Spermatozoa/metabolism , Structure-Activity Relationship
4.
Front Oncol ; 9: 480, 2019.
Article in English | MEDLINE | ID: mdl-31231612

ABSTRACT

Due to their crucial role in cell metabolism and homeostasis, alterations in mitochondrial biology and function have been related to the progression of diverse diseases including cancer. One of the consequences associated to mitochondrial dysfunction is the production of reactive oxygen species (ROS). ROS are known to have a controversial role during cancer initiation and progression and although several studies have tried to manipulate intracellular ROS levels using antioxidants or pro-oxidation conditions, it is not yet clear how to target oxidation for cancer therapy. In this study, we found differences in mitochondrial morphology in breast cancer cells when compared to a non-tumorigenic cell line and differences in mitochondrial function among breast cancer subtypes when exploring gene-expression data from the TCGA tumor dataset. Interestingly, we found increased ROS levels in triple negative breast cancer (TNBC) cell lines and a dependency on ROS for survival since antioxidant treatment induced cell death in TNBC cells but not in an estrogen receptor positive (ER+) cell line. Moreover, we identified the mitochondria as the main source of ROS in TNBC cell lines. Our results indicate a potential use for ROS as a target for therapy in the TNBC subtype which currently has the worst prognosis among all breast cancers and remains as the only breast cancer subtype which lacks a targeted therapy.

5.
Int J Mol Sci ; 21(1)2019 Dec 30.
Article in English | MEDLINE | ID: mdl-31905880

ABSTRACT

An increase in intracellular Ca2+ concentration ([Ca2+]i) plays a key role in controlling endothelial functions; however, it is still unclear whether endothelial Ca2+ handling is altered by type 2 diabetes mellitus, which results in severe endothelial dysfunction. Herein, we analyzed for the first time the Ca2+ response to the physiological autacoid ATP in native aortic endothelium of obese Zucker diabetic fatty (OZDF) rats and their lean controls, which are termed LZDF rats. By loading the endothelial monolayer with the Ca2+-sensitive fluorophore, Fura-2/AM, we found that the endothelial Ca2+ response to 20 µM and 300 µM ATP exhibited a higher plateau, a larger area under the curve and prolonged duration in OZDF rats. The "Ca2+ add-back" protocol revealed no difference in the inositol-1,4,5-trisphosphate-releasable endoplasmic reticulum (ER) Ca2+ pool, while store-operated Ca2+ entry was surprisingly down-regulated in OZDF aortae. Pharmacological manipulation disclosed that sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) activity was down-regulated by reactive oxygen species in native aortic endothelium of OZDF rats, thereby exaggerating the Ca2+ response to high agonist concentrations. These findings shed new light on the mechanisms by which type 2 diabetes mellitus may cause endothelial dysfunction by remodeling the intracellular Ca2+ toolkit.


Subject(s)
Aorta/metabolism , Calcium/metabolism , Diabetes Mellitus, Type 2/metabolism , Endothelium, Vascular/metabolism , Animals , Calcium Signaling/physiology , Diabetes Mellitus, Experimental , Disease Models, Animal , Endoplasmic Reticulum/metabolism , Fura-2/analogs & derivatives , Glucose Tolerance Test , Homeostasis , Insulin Resistance , Male , Plasma Membrane Calcium-Transporting ATPases/metabolism , Rats , Rats, Zucker , Sarcoplasmic Reticulum Calcium-Transporting ATPases/metabolism , Sodium-Calcium Exchanger/metabolism
6.
Integr Cancer Ther ; 17(3): 654-664, 2018 09.
Article in English | MEDLINE | ID: mdl-29652200

ABSTRACT

Plants from the Bursera genus are widely distributed in the tropical dry forests of Mexico. In traditional medicine, extracts from different species of Bursera have been used for a wide range of biological activities, including the treatment of cancer-related symptoms. Compounds present in the Bursera genus include lignans, flavonoids, steroids, short-chain aliphatic alkanes, acetates, alcohols, ketones, and terpenoids. In some instances, secondary metabolites of these classes of compounds may induce cytotoxicity, and therefore we sought to investigate the effects of B. copallifera leaf extracts in breast cancer cell lines to evaluate their potential therapeutic value for the treatment of breast cancer, one of the most prevalent types of cancer in women worldwide. Two B. copallifera leaf extracts exerted cytotoxic effects on both the MCF7 and MDA-MB-231 breast cancer cell line models. The cytotoxic effect was more evident in the MDA-MB-231 triple negative cell line inhibiting also the migration of these cells. We identified hydroxycinnamic acid and flavonol derivatives as major phenolic components of the extracts. Our results strongly suggest a potential use of the Bursera leaf extracts rich in phenolic compounds, their individual phenolic compounds, or their combinations for the treatment of breast cancer.


Subject(s)
Breast Neoplasms/drug therapy , Bursera/chemistry , Cell Movement/drug effects , Cytotoxins/pharmacology , Plant Extracts/pharmacology , Cell Line, Tumor , Female , Humans , MCF-7 Cells
7.
Res Vet Sci ; 114: 218-224, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28502901

ABSTRACT

Porcine rubulavirus (PorPV), also known as La Piedad Michoacan Virus (LPMV) causes encephalitis and reproductive failure in newborn and adult pigs, respectively. The hemagglutinin-neuraminidase (HN) glycoprotein is the most exposed and antigenic of the virus proteins. HN plays central roles in PorPV infection; i.e., it recognizes sialic acid-containing cell receptors that mediate virus attachment and penetration; in addition, its neuraminidase (sialic acid releasing) activity has been proposed as a virulence factor. This work describes the purification and characterization of PorPV HN protein (isolate PAC1). The specificity of neuraminidase is restricted to sialyl(α2,3)lactose (3SL). HN showed typical Michaelis-Menten kinetics with fetuin as substrate (km=0.029µM, Vmax=522.8nmolmin-1mg-1). When 3SL was used as substrate, typical cooperative kinetics were found (S50=0.15µM, Vmax=154.3nmolmin-1mg-1). The influenza inhibitor zanamivir inhibited the PorPV neuraminidase with IC50 of 0.24µM. PorPV neuraminidase was activated by Ca2+ and inhibited by nucleoside triphosphates with the level of inhibition depending on phosphorylation level. The present results open possibilities to study the role of neuraminidase in the pathogenicity of PorPV infection and its potential inhibitors.


Subject(s)
Neuraminidase/genetics , Rubulavirus Infections/veterinary , Rubulavirus/enzymology , Swine Diseases/virology , Viral Proteins/genetics , Animals , HN Protein/genetics , HN Protein/metabolism , Kinetics , Neuraminidase/metabolism , Rubulavirus Infections/virology , Swine , Viral Proteins/metabolism
8.
Syst Biol Reprod Med ; 62(5): 343-52, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27463087

ABSTRACT

UNLABELLED: The present study evaluates the possible antifertility effect of aqueous crude extract (OBACE) of Echeveria gibbiflora, a plant that belongs to the crassulaceae family, used in traditional Mexican medicine as a vaginal post coital rinse to prevent pregnancy and shown to have an immobilization/agglutination effect on sperm of different mammal species. We evaluated the effect of OBACE on functional parameters of mouse sperm, such as viability, capacitation, and acrosome reaction. In addition, due to the high concentrations of calcium bis-(hydrogen-1-malate) hexahydrate [Ca (C4H5O5)2•6H2O] present in this plant extract, we evaluated its effect on Ca(2+) influx in mouse sperm under capacitating conditions. Moreover, we determined the acute toxicity of OBACE and its in vivo effect in mouse sperm motility administering a single daily dose of 50 and 100 mg/kg during seven days, intraperitoneally. The sperm viability was not affected by the presence of different concentrations of OBACE, however, the capacitation and acrosome reaction suffered a significant decrease in a concentration-dependent manner, coinciding with the reduction of Ca(2+) influx. Furthermore, OBACE displayed an LD50 of 3,784.42 mg/kg and can be classified as a low toxic substance. Also, in vivo OBACE showed an inhibition of total and progressive motility on mouse sperm alongside a significant decrease of motility kinematic parameters and IVF rates. The results confirm the antifertility effect of this plant used in Mexican folk medicine. Further study on OBACE as a possible contraceptive treatment is warranted because of its activity and low in vivo toxicity. ABBREVIATIONS: ALH: lateral amplitude; AP: acid phosphatase; BCF: beat frequency; BSA: bovine serum albumine; CTC: chlortetracycline; FDA: fluorescein diacetate; Fura-2 AM: fura-2-acetoxymethyl ester; HIV: human immunodeficiency virus; IVF: in vitro fertilization; OBACE: aqueous crude extract of Echeveria gibbiflora; PI: propidum iodide; SN: supernatant; VAP: average path velocity; VCL: track speed; VSL: straight line velocity.


Subject(s)
Contraceptive Agents/pharmacology , Crassulaceae/chemistry , Plant Extracts/pharmacology , Spermatozoa/drug effects , Acrosome Reaction/drug effects , Animals , Fertilization in Vitro/drug effects , Male , Medicine, Traditional , Mexico , Mice , Sperm Capacitation/drug effects , Sperm Motility/drug effects
9.
Virus Res ; 185: 1-9, 2014 Jun 24.
Article in English | MEDLINE | ID: mdl-24657783

ABSTRACT

Influenza A virus genomic segments eight codes for non-structural 1 (NS1) protein that is involved in evasion of innate antiviral response, and nuclear export protein (NEP) that participates in the export of viral ribonucleoprotein (RNP) complexes, transcription and replication. Tumor necrosis factor alpha (TNF-α) is highly expressed during influenza virus infections and is considered an anti-infective cytokine. NS1 and NEP proteins were overexpressed and their role on TNF-α expression was evaluated. Both TNF-α mRNA and protein increased in cells transfected with NEP but not with NS1. We further investigate if NS1 or NEP regulates the activity of TNF-α promoter. In the presence of NEP the activity of TNF-α promoter increased significantly compared with the control (83.5±2.9 vs. 30.9±2.8, respectively; p=0.001). This effect decreased 15-fold when the TNF-α promoter distal region was deleted, suggesting the involvement of mitogen-activated protein kinases (MAPK) and NF-kB response elements. This was corroborated by testing the effect produced on TNF-α promoter by the treatment with Raf/MEK/ERK (U0126), NF-kB (Bay-11-7082) and PI3K (Ly294-002) cell signaling inhibitors. Treatment with U0126 and Bay-117082 reduced the activity of TNF-α promoter mediated by NEP (41.5±3.2, 70% inhibition; and 80.6±7.4, 35% inhibition, respectively) compared to mock-treated control. The results suggest a new role for NEP protein that participates in the transcriptional regulation of human TNF-α expression.


Subject(s)
Influenza A virus/genetics , Influenza A virus/metabolism , Influenza, Human/genetics , Tumor Necrosis Factor-alpha/genetics , Gene Expression Regulation , Humans , Influenza, Human/metabolism , Influenza, Human/virology , Signal Transduction , Transfection , Tumor Necrosis Factor-alpha/metabolism , Viral Nonstructural Proteins/genetics , Viral Nonstructural Proteins/metabolism
10.
Rev Neurol ; 56(9): 456-63, 2013 May 01.
Article in Spanish | MEDLINE | ID: mdl-23629747

ABSTRACT

INTRODUCTION: Neurocysticercosis (NCC) is a parasitic infection caused by the establishment of Taenia solium cysticerci in the central nervous system. The larval stage of the parasite also affects the pig, which is the essential intermediate host for transmission. For this reason, many researchers have focused on identifying protective antigens to prevent swine cysticercosis and interrupt the transmission. These include S3Pvac vaccine antigens. Vaccine is constituted by three protective synthetic peptides: KETc1, KETc12 and GK1. AIM. To evaluate the effect of the vaccine peptides KETc1, KETc12 and GK1 in mononuclear cells of patients with neuro-cysticercosis and healthy individuals. SUBJECTS AND METHODS: Comparative, prospective, transverse study. We studied the proliferation and cytokine profile induced by the three peptides in mononuclear cells from three patients with active NCC, 16 patients by calcified NCC and 16 healthy subjects. RESULTS: KETc1 induces low levels of proliferation in cells from patients with active and controlled NCC, both in lymphocytes and in monocytes. KETc12 and GK-1 induce positive proliferation levels of monocytes in healthy subjects. CONCLUSIONS: KETc1 peptide could be used as an adjuvant in the treatment of patients with active NCC, as induced a Th2 response also GK1 peptide as stimulator of monocyte/macrophage in immunizations with other proteins.


TITLE: Efecto in vitro de la vacuna S3Pvac contra cisticercosis en celulas mononucleares humanas.Introduccion. La neurocisticercosis (NCC) es una infeccion parasitaria generada por el establecimiento de cisticercos de Taenia solium en el sistema nervioso central. La fase larvaria del parasito tambien afecta al cerdo, que es el huesped intermediario indispensable para la transmision. Por tal motivo, muchos investigadores se han enfocado en identificar antigenos protectores para prevenir la cisticercosis porcina e interrumpir la transmision. Entre ellos figuran los antigenos de la vacuna S3Pvac, constituida por tres peptidos protectores: KETc1, KETc12 y GK1. Objetivo. Evaluar el efecto de los peptidos vacunales KETc1, KETc12 y GK1 en celulas mononucleares de pacientes con NCC e individuos sanos. Sujetos y metodos. Estudio comparativo, prospectivo y transversal. Se analizo la proliferacion y el perfil de citocinas inducidos por los tres peptidos en celulas mononucleares de tres pacientes con NCC activa, 16 pacientes con NCC calcificada y 16 sujetos sanos. Resultados. KETc1 induce bajos niveles de proliferacion en las celulas de los pacientes con NCC activa y controlada, tanto en linfocitos como en monocitos. KETc12 y GK-1 inducen niveles positivos de proliferacion de monocitos en sujetos sanos. Conclusiones. El peptido KETc1 podria usarse como coadyuvante en el tratamiento de los pacientes con NCC activa, ya que indujo una respuesta Th2; y el peptido GK1, como estimulador del monocito/macrofago en inmunizaciones con otras proteinas.


Subject(s)
Antigens, Helminth/immunology , Calcinosis/immunology , Cysticercus/immunology , Monocytes/drug effects , Neurocysticercosis/immunology , Vaccines, Subunit/pharmacology , Adjuvants, Immunologic , Adolescent , Adult , Aged , Animals , Antigens, Helminth/analysis , Calcinosis/blood , Cell Division/drug effects , Cells, Cultured , Cross-Sectional Studies , Cysticercus/ultrastructure , Drug Evaluation, Preclinical , Female , Fluorescent Antibody Technique, Indirect , Humans , In Vitro Techniques , Interferon-gamma/metabolism , Interleukins/metabolism , Lymphocytes/drug effects , Lymphocytes/metabolism , Male , Middle Aged , Monocytes/metabolism , Neurocysticercosis/blood , Peptide Fragments/chemical synthesis , Peptide Fragments/immunology , Prospective Studies , Vaccines, Subunit/immunology , Young Adult
11.
Rev. neurol. (Ed. impr.) ; 56(9): 456-463, 1 mayo, 2013. ilus, tab
Article in Spanish | IBECS | ID: ibc-112440

ABSTRACT

Introducción. La neurocisticercosis (NCC) es una infección parasitaria generada por el establecimiento de cisticercos de Taenia solium en el sistema nervioso central. La fase larvaria del parásito también afecta al cerdo, que es el huéspedintermediario indispensable para la transmisión. Por tal motivo, muchos investigadores se han enfocado en identificar antígenos protectores para prevenir la cisticercosis porcina e interrumpir la transmisión. Entre ellos figuran los antígenos de la vacuna S3Pvac, constituida por tres péptidos protectores: KETc1, KETc12 y GK1. Objetivo. Evaluar el efecto de los péptidos vacunales KETc1, KETc12 y GK1 en células mononucleares de pacientes con NCC e individuos sanos. Sujetos y métodos. Estudio comparativo, prospectivo y transversal. Se analizó la proliferación y el perfil de citocinas inducidos por los tres péptidos en células mononucleares de tres pacientes con NCC activa, 16 pacientes con NCC calcificada y 16 sujetos sanos. Resultados. KETc1 induce bajos niveles de proliferaci en las células de los pacientes con NCC activa y controlada, tanto en linfocitos como en monocitos. KETc12 y GK-1 inducen niveles positivos de proliferación de monocitos en sujetos sanos. Conclusiones. El péptido KETc1 podría usarse como coadyuvante en el tratamiento de los pacientes con NCC activa, ya que indujo una respuesta Th2; y el péptido GK1, como estimulador del monocito/macrófago en inmunizaciones con otras proteínas (AU)


Introduction. Neurocysticercosis (NCC) is a parasitic infection caused by the establishment of Taenia solium cysticerci in the central nervous system. The larval stage of the parasite also affects the pig, which is the essential intermediate host for transmission. For this reason, many researchers have focused on identifying protective antigens to prevent swine cysticercosis and interrupt the transmission. These include S3Pvac vaccine antigens. Vaccine is constituted by three protective synthetic peptides: KETc1, KETc12 and GK1. Aim. To evaluate the effect of the vaccine peptides KETc1, KETc12 and GK1 in mononuclear cells of patients with neurocysticercosis and healthy individuals. Subjects and methods. Comparative, prospective, transverse study. We studied the proliferation and cytokine profile induced by the three peptides in mononuclear cells from three patients with active NCC, 16 patients by calcified NCC and 16 healthy subjects. Results. KETc1 induces low levels of proliferation in cells from patients with active and controlled NCC, both in lymphocytes and in monocytes. KETc12 and GK-1 induce positive proliferation levels of monocytes in healthy subjects. Conclusions. KETc1 peptide could be used as an adjuvant in the treatment of patients with active NCC, as induced a Th2 response also GK1 peptide as stimulator of monocyte/macrophage in immunizations with other proteins (AU)


Subject(s)
Humans , Neurocysticercosis/prevention & control , Taenia/pathogenicity , Vaccines/administration & dosage , Prospective Studies , Leukocytes, Mononuclear/immunology
12.
PLoS One ; 7(4): e35477, 2012.
Article in English | MEDLINE | ID: mdl-22530029

ABSTRACT

Previously, it was suggested a relation between the presence of apoptosis markers with cytoplasm in mammalian sperm. In this work, flow cytometry, confocal microscopy and image analysis were used to analyze the relationship between active caspase-3 and -7 and intracellular esterases expression in ejaculated or epididymal ram sperm. Sperm obtained from ejaculates from the caput, corpus, or cauda of the epididymis were treated with an inhibitor of active caspase-3 and -7 and a marker of cytoplasmic esterases. Additionally, ejaculated sperm were incubated for one, two, or three hours before evaluation for active caspases. Sperm subpopulations positive for active caspases and/or intracellular esterases were detected by flow cytometry and confocal microscopy; however, image analysis of confocal images showed that the correlation between active caspases and cytoplasmic esterases in sperm is region-specific. Lower values of Spearman correlation coefficients were found when whole sperm or head sperm was analyzed; however, a high correlation was observed for midpiece sperm. Incubation of sperm for two or three hours promoted the autoactivation of caspases. It has been suggested that the presence of apoptotic markers in sperm are related with a process of abortive apoptosis and with errors during spermiogenesis. Our results permit us suggest that the origin of the relationship between active caspases and cytoplasmic esterases is due to differentiation errors occurring during spermiogenesis because the percentages of sperm with active caspases are not different in the caput, corpus, or cauda of the epididymis. In this study we demonstrate that existing sperm subpopulations can express active caspases and intracellular esterases and that the correlation between these molecules is high in midpiece sperm.


Subject(s)
Caspases/metabolism , Cytoplasm/enzymology , Spermatozoa/enzymology , Animals , Apoptosis/physiology , Carboxylesterase/metabolism , Ejaculation , Epididymis/cytology , Male , Microscopy, Confocal , Spermatozoa/cytology
13.
Syst Biol Reprod Med ; 54(6): 221-30, 2008.
Article in English | MEDLINE | ID: mdl-19052960

ABSTRACT

During spermatogenesis, changes in sperm nuclear morphology are associated with the replacement of core somatic histones by protamines. Although protamines are the major nucleoproteins of mature sperm, not all species totally replace the histones. Histone H1, along with protamines, mediates chromatin condensation into an insoluble complex that is transcriptionally inactive. In vitro, heparin-reduced glutathione causes sperm decondensation, and the structures formed are morphologically similar to the in vivo male pronucleus. To study the participation of histone H1 in bovine sperm chromatin remodelling, we measured the presence and release of histone H1 by immunofluorescence, acetic acid-urea-triton-polyacrylamide gel electrophoresis, and immunoblotting. Nuclear decondensation was induced by 80 microM heparin and 15.0 mM reduced glutathione (GSH) for 7, 14, and 21 h at 37 degrees C. Additionally, nucleons, composed of nuclei isolated from the sperm, were decondensed with 20.0 microM heparin and 5.0 mM GSH for 4.0 h at 37 degrees C. Controls were incubated in buffer for similar periods of time. Immunofluorescent localization of histone H1 was carried out with mouse monoclonal antibody, and DNA localization was visualized by 0.001% quinacrine staining. Chromatin decondensation was accompanied by increased sperm nuclei and nucleon surface area. We observed that histone H1 was localized exclusively in the nuclei of intact sperm and nucleons. Histone H1 immunofluorescent intensity did not change in control samples but decreased over time in samples treated with heparin-GSH. There was a negative correlation between the surface area of sperm nuclei and immunohistochemical intensity of histone H1 (P < 0.05). Nucleon decondensation showed a similar relationship. By electrophoresis and immunoblotting, we verified the loss of histone H1 from the sperm and nucleons and its release into the incubation media. Based on these results, we propose that histone H1 is present in the bovine sperm nuclei. H1 depletion may participate in chromatin decondensation and nuclear swelling induced by heparin-GSH.


Subject(s)
Chromatin/ultrastructure , Glutathione/pharmacology , Heparin/pharmacology , Histones/analysis , Histones/metabolism , Spermatozoa/ultrastructure , Animals , Antibodies, Monoclonal , Cattle , Cell Nucleus/chemistry , Cell Nucleus/ultrastructure , Chromatin/drug effects , Electrophoresis, Polyacrylamide Gel , Fluorescent Antibody Technique , Immunoblotting , Male , Spermatozoa/chemistry , Spermatozoa/metabolism
14.
Zygote ; 16(1): 1-8, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18221575

ABSTRACT

Oocytes undergo numerous biochemical and morphological changes during their development from preantral to preovulatory phases. In vitro studies have suggested several compounds that might induce oocyte maturation. Heparin is a natural component of ooplasm, follicular fluid and uterine fluid and previous studies indicated that it might act as a chromatin maturation factor in bovine oocytes. We tested this hypothesis in vitro by timing germinal vesicle breakdown (GVBD) and first polar body (PB) formation without any other natural or introduced factors that might influence the rate of oocyte maturation. We also determined if these oocytes could be fertilized. Bovine oocytes were incubated in a salt medium and TCM 199 supplemented with different concentrations of heparin for 24 h at 37.5 degrees C in a humidified atmosphere of 5% CO2. With 1.0 and 6.5 mg/ml heparin, the time of GVBD was reduced from 4.7+/-1.1 h to about 1.5 h and the time of first PB formation was reduced from 22.0+/-1.1 h to 9.0-11.0 h in salt medium. In TCM 199, only 6.5 mg/ml heparin significantly reduced the time of PB formation. In both incubation media, 1.0 and 6.5 mg/ml heparin induced GVBD, extrusion of the first PB and formation of the metaphase II nucleus. Moreover, heparin did not interfere with the fertilization of oocytes matured in TCM 199. Based on the results, we propose that heparin plays an important role in the rearrangement of the oocyte chromatin and acts as an oocyte maturation factor.


Subject(s)
Anticoagulants/pharmacology , Cell Nucleus/drug effects , Fertilization in Vitro/veterinary , Heparin/pharmacology , Oocytes/drug effects , Ovarian Follicle/drug effects , Animals , Cattle , Cell Nucleus/metabolism , DNA/chemistry , DNA/metabolism , Female , In Vitro Techniques , Male , Metaphase , Oocytes/physiology , Ovarian Follicle/cytology , Spermatozoa/drug effects , Spermatozoa/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...