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1.
Biol Reprod ; 104(5): 1162-1180, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33624745

RESUMO

Atrazine (ATZ) is an extensively used herbicide and ubiquitous environmental contaminant. ATZ and its metabolite, diaminochlorotriazine (DACT), cause several cellular and functional alterations in spermatozoa. We aimed to examine the effect of ATZ/DACT on spermatozoon DNA integrity, fertilization competence, embryonic development, and transcriptome profile of in vitro-produced embryos derived from fertilization with pre-exposed sperm. Bovine spermatozoa exposed to ATZ (0.1 or 1 µM) or DACT (1 or 10 µM) during in vitro capacitation were used for in vitro fertilization of untreated oocytes. Cleavage and blastocyst-formation rates were evaluated 42 h and 7 days postfertilization, respectively. The association between DNA fragmentation and apoptosis (annexin V kit) was determined. Fertilization competence of annexin-positive (AV+) and annexin-negative (AV-) spermatozoa was examined. Microarray analysis was performed for 7-day blastocysts. Intracytoplasmic sperm injection was performed with control (AV+, AV-) and DACT (AV+, AV-) spermatozoa. Cleavage rates did not differ between groups and blastocyst formation tended to be higher for AV- vs. AV+ in both control and DACT groups, suggesting that acrosome reaction, rather than DNA fragmentation, underlies the reduced cleavage. Transcriptomic analysis revealed 139 and 230 differentially expressed genes in blastocysts derived from ATZ- and DACT-exposed spermatozoa, respectively, relative to controls. Proteomic analysis shown differential expression of proteins in ATZ- or DACT-treated spermatozoa, in particular proteins related to cellular processes and biological pathways. Therefore, we assume that factors delivered by the spermatozoa, regardless of DNA fragmentation, are also involved. Overall, the current study reveals a deleterious carryover effect of ATZ/DACT from the spermatozoa to the developing embryo.


Assuntos
Atrazina/efeitos adversos , Bovinos/fisiologia , Herbicidas/efeitos adversos , Espermatozoides/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Animais , Embrião de Mamíferos/efeitos dos fármacos , Embrião de Mamíferos/metabolismo , Masculino , Espermatozoides/metabolismo
2.
Eur J Anaesthesiol ; 37(5): 402-412, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32068571

RESUMO

BACKGROUND: Severe neurological impairment is a problem after subarachnoid haemorrhage (SAH). Although volatile anaesthetics, such as sevoflurane, have demonstrated protective properties in many organs, their use in cerebral injury is controversial. Cerebral vasodilation may lead to increased intracranial pressure (ICP), but at the same time volatile anaesthetics are known to stabilise the SAH-injured endothelial barrier. OBJECTIVE: To test the effect of sevoflurane on ICP and blood-brain barrier function. DESIGN: Randomised study. PARTICIPANTS: One hundred male Wistar rats included, 96 analysed. INTERVENTIONS: SAH was induced by the endoluminal filament method under ketamine/xylazine anaesthesia. Fifteen minutes after sham surgery or induction of SAH, adult male Wistar rats were randomised to 4 h sedation with either propofol or sevoflurane. MAIN OUTCOME MEASURES: Mean arterial pressure (MAP), ICP, extravasation of water (small), Evan's blue (intermediate) and IgG (large molecule) were measured. Zonula occludens-1 (ZO-1) and beta-catenin (ß-catenin), as important representatives of tight and adherens junction proteins, were determined by western blot. RESULTS: Propofol and sevoflurane sedation did not affect MAP or ICP in SAH animals. Extravasation of small molecules was higher in SAH-propofol compared with SAH-sevoflurane animals (79.1 ±â€Š0.9 vs. 78.0 ±â€Š0.7%, P = 0.04). For intermediate and large molecules, no difference was detected (P = 0.6 and P = 0.2). Both membrane and cytosolic fractions of ZO-1 as well as membrane ß-catenin remained unaffected by the injury and type of sedation. Decreased cytosolic fraction of ß-catenin in propofol-SAH animals (59 ±â€Š15%) was found to reach values of sham animals (100%) in the presence of sevoflurane in SAH animals (89 ±â€Š21%; P = 0.04). CONCLUSION: This experiment demonstrates that low-dose short-term sevoflurane sedation after SAH in vivo did not affect ICP and MAP and at the same time may attenuate early brain oedema formation, potentially by preserving adherens junctions. TRIAL REGISTRATION: No 115/2014 Veterinäramt Zürich.


Assuntos
Junções Aderentes , Anestesia , Edema Encefálico , Sevoflurano , Hemorragia Subaracnóidea , beta Catenina , Animais , Masculino , Ratos , Junções Aderentes/efeitos dos fármacos , Anestesia/efeitos adversos , beta Catenina/metabolismo , Edema Encefálico/induzido quimicamente , Ratos Wistar , Sevoflurano/administração & dosagem , Sevoflurano/efeitos adversos , Hemorragia Subaracnóidea/induzido quimicamente
3.
Anesth Analg ; 127(4): 1058-1065, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30216289

RESUMO

BACKGROUND: Randomized controlled trials (RCTs) data demonstrate that sevoflurane postconditioning improves clinical outcomes of liver resection with inflow occlusion, presumably due to hepatocyte protection from ischemic injury. However, mechanisms remain unclear. This study examines liver biopsy samples obtained in an RCT of sevoflurane postconditioning to test the hypothesis that sevoflurane attenuates hepatocyte apoptosis. METHODS: Messenger ribonucleic acid (mRNA) of pro- and antiapoptotic regulators Bax and B-cell lymphoma 2 (Bcl2) was examined in hepatic biopsies obtained during the RCT. Hepatic stellate cells (HSCs) and hepatocytes were exposed to hypoxia/reoxygenation (H/R) in vitro to evaluate the effect of sevoflurane postconditioning on apoptosis. The role of HSC as a potential apoptosis trigger in hepatocytes through the production of reactive oxygen species induced by H/R was explored by transferring supernatants from H/R-exposed HSC to hepatocytes as target cells. RESULTS: In patients of the RCT, the Bax/Bcl2 mRNA ratio in liver tissue was markedly decreased in the sevoflurane arm (25% ± 21% reduction; P = .001). In vitro, H/R increased reactive oxygen species production in HSC by 33% ± 16% (P = .025), while it was abolished in the presence of sevoflurane (P < .001). In hepatocytes, caspase was minimally activated by H/R. However, incubation of hepatocytes with supernatants of HSC, previously exposed to H/R, increased caspase activity by 28% ± 13% (P < .001). When exposed to supernatants from HSC undergoing sevoflurane postconditioning, caspase activation in hepatocytes was reduced by 20% ± 9% (P < .001), similarly to the sevoflurane effect on the BAX/Bcl2 mRNA ratio in the liver samples. CONCLUSIONS: The study shows that sevoflurane postconditioning affects apoptosis of hepatocytes after ischemia-reperfusion injury in patients. It also demonstrates that HSC may be the effector cells of sevoflurane protection.


Assuntos
Antioxidantes/farmacologia , Células Estreladas do Fígado/efeitos dos fármacos , Hepatopatias/prevenção & controle , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Sevoflurano/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/metabolismo , Citoproteção , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Comunicação Parácrina/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Transdução de Sinais/efeitos dos fármacos , Pesquisa Translacional Biomédica , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
5.
Zygote ; 24(1): 70-82, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25532584

RESUMO

We examined the association between progressive motility of spermatozoa and in vitro fertilization (IVF) competence of bovine ejaculates. Fresh semen was evaluated using a computerized sperm quality analyzer for bulls using progressive motility as the primary parameter. Ejaculates with high progressive motility (HPM; >81%) were compared with those with low progressive motility (LPM; 0.05). Examination of sperm morphology revealed a higher proportion of spermatozoa with abnormal morphology (P < 0.01) in LPM versus HPM ejaculates, the predominant abnormal feature being a bent tail (P < 0.05). Sperm viability, acrosome integrity and DNA fragmentation did not differ between HPM and LPM samples. Mitochondrial membrane potential was higher (P < 0.01) in HPM versus LPM semen. Zinc concentrations in the seminal plasma correlated with progressive motility (R2 = 0.463, P = 0.03). In addition, representative ejaculates from HPM and LPM groups were cryopreserved in straws and used for IVF. The proportions of embryos cleaved to 2- and 4-cell stages (88.1 ± 1.1 versus 80.5 ± 1.7, P = 0.001) and developed to blastocysts (33.5 ± 1.6 versus 23.5 ± 2.2, P = 0.026) were higher for HPM than LPM semen. The total cell number of embryos and blastocyst apoptotic index did not differ between groups. Although sperm progressive motility is associated with IVF competence, further examination is required to determine whether progressive motility can serve as a predictor of semen fertilization capacity in vivo.


Assuntos
Análise do Sêmen/métodos , Sêmen/fisiologia , Motilidade dos Espermatozoides/fisiologia , Animais , Blastocisto/fisiologia , Bovinos , Criopreservação , Feminino , Fertilização in vitro , Masculino , Espermatozoides/patologia
6.
Clin Exp Immunol ; 181(3): 468-79, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25925908

RESUMO

Volatile anaesthetics such as sevoflurane attenuate inflammatory processes, thereby impacting patient outcome significantly. Their inhalative administration is, however, strictly limited to controlled environments such as operating theatres, and thus an intravenously injectable immunomodulatory drug would offer distinct advantages. As protective effects of volatile anaesthetics have been associated with the presence of trifluorinated carbon groups in their basic structure, in this study we investigated the water-soluble sevoflurane metabolite hexafluoro-2-propanol (HFIP) as a potential immunomodulatory drug in a rat model of endotoxic shock. Male Wistar rats were subjected to intravenous lipopolysaccharide (LPS) and thereafter were treated with HFIP. Plasma and tissue inflammatory mediators, neutrophil invasion, tissue damage and haemodynamic stability were the dedicated end-points. In an endotoxin-induced endothelial cell injury model, underlying mechanisms were elucidated using gene expression and gene reporter analyses. HFIP reduced the systemic inflammatory response significantly and decreased endotoxin-induced tissue damage. Additionally, the LPS-provoked drop in blood pressure of animals was resolved by HFIP treatment. Pathway analysis revealed that the observed attenuation of the inflammatory process was associated with reduced nuclear factor kappa B (NF-κΒ) activation and suppression of its dependent transcripts. Taken together, intravenous administration of HFIP exerts promising immunomodulatory effects in endotoxaemic rats. The possibility of intravenous administration would overcome limitations of volatile anaesthetics, and thus HFIP might therefore represent an interesting future drug candidate for states of severe inflammation.


Assuntos
Adjuvantes Imunológicos/farmacologia , Endotoxemia/prevenção & controle , Propanóis/farmacologia , Choque Séptico/prevenção & controle , Animais , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Endotoxemia/metabolismo , Ensaio de Imunoadsorção Enzimática , Expressão Gênica/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Inflamação/sangue , Inflamação/metabolismo , Inflamação/prevenção & controle , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Modelos Lineares , Lipopolissacarídeos/farmacologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Éteres Metílicos/metabolismo , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Propanóis/metabolismo , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sevoflurano , Choque Séptico/sangue , Choque Séptico/induzido quimicamente
7.
Br J Anaesth ; 114(1): 143-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24989774

RESUMO

BACKGROUND: Growing evidence suggests a protective effect of volatile anaesthetics in ischaemia-reperfusion (I/R)-injury, and the accumulation of neutrophils is a crucial event. Pro-inflammatory cytokines carrying the C-X-C-motif including interleukin-8 (IL-8) and CXC-ligand 1 (CXCL1) activate CXC receptor-1 (CXCR1; stimulated by IL-8), CXC receptor-2 (CXCR2; stimulated by IL-8 and CXCL1), or both to induce CD11b-dependent neutrophil transmigration. Inhibition of CXCR1, CXCR2, or both reduces I/R-injury by preventing neutrophil accumulation. We hypothesized that interference with CXCR1/CXCR2 signalling contributes to the well-established beneficial effect of volatile anaesthetics in I/R-injury. METHODS: Isolated human neutrophils were stimulated with IL-8 or CXCL1 and exposed to volatile anaesthetics (sevoflurane/desflurane). Neutrophil migration was assessed using an adapted Boyden chamber. Expression of CD11b, CXCR1, and CXCR2 was measured by flow cytometry. Blocking antibodies against CXCR1/CXCR2/CD11b and phorbol myristate acetate were used to investigate specific pathways. RESULTS: Volatile anaesthetics reduced CD11b-dependent neutrophil transmigration induced by IL-8 by >30% and CD11b expression by 18 and 27% with sevoflurane/desflurane, respectively. This effect was independent of CXCR1/CXCR2 expression and CXCR1/CXCR2 endocytosis. Inhibition of CXCR1 signalling did not affect downregulation of CD11b with volatile anaesthetics. Blocking of CXCR2-signalling neutralized effects by volatile anaesthetics on CD11b expression. Specific stimulation of CXCR2 with CXCL1 was sufficient to induce upregulation of CD11b, which was impaired with volatile anaesthetics. No effect of volatile anaesthetics was observed with direct stimulation of protein kinase C located downstream of CXCR1/CXCR2. CONCLUSION: Volatile anaesthetics attenuate neutrophil inflammatory responses elicited by CXC cytokines through interference with CXCR2 signalling. This might contribute to the beneficial effect of volatile anaesthetics in I/R-injury.


Assuntos
Anestésicos Inalatórios/farmacologia , Inflamação/sangue , Neutrófilos/efeitos dos fármacos , Receptores de Interleucina-8B/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Adulto , Anestésicos Inalatórios/sangue , Desflurano , Feminino , Citometria de Fluxo/métodos , Humanos , Isoflurano/análogos & derivados , Isoflurano/sangue , Isoflurano/farmacologia , Masculino , Éteres Metílicos/sangue , Éteres Metílicos/farmacologia , Pessoa de Meia-Idade , Receptores de Interleucina-8B/sangue , Sevoflurano , Adulto Jovem
8.
Reprod Fertil Dev ; 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25891636

RESUMO

Subclinical chronic mastitis was induced to examine the effects on oocyte developmental competence. Uninfected Holstein cows were intramammary administrated with serial (every 48h for 20 days) low doses of toxin of Staphylococcus aureus origin (Gram-positive; G+), endotoxin of Escherichia coli origin (Gram-negative; G-) or sterile saline (control). Follicular fluid of toxin- and saline-treated cows was aspirated from preovulatory follicles and used as maturation medium. Oocytes harvested from ovaries collected at the abattoir were matured and then fertilised and cultured for 8 days. The percentage of oocytes undergoing nuclear maturation, determined by meiotic nuclear stages, did not differ between groups. Cytoplasmic maturation, determined by cortical granule distribution, was affected by both toxins (PPPPTGS2) mRNA increased, whereas that of growth differentiation factor 9 (GDF9) decreased in matured oocytes. In addition, PTGS2 expression increased and POU class 5 homeobox 1 (POU5F1) expression decreased in 4-cell embryos developed from both G+ and G- oocytes. Thus, regardless of toxin type, subclinical mastitis disrupts oocyte cytoplasmic maturation and alters gene expression in association with reduced developmental competence.

9.
Reproduction ; 147(1): 33-43, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24129150

RESUMO

Mastitis is associated with decreased fertility in dairy cows. In the current study, we created an experimental model to simulate short-term mastitis by a single intramammary administration of Gram-negative endotoxin of Escherichia coli origin (G-), or Gram-positive toxin of Staphylococcus aureus origin (G+), to examine the effect of mastitis on oocyte developmental competence. Healthy Holstein cows were synchronized, and follicular fluid (FF) of cows treated with G+ or G- and of uninfected cows (controls) was aspirated from the preovulatory follicles by transvaginal ultrasound procedure. The aspirated FF was used as maturation medium for in vitro embryo production. The distribution of matured oocytes into different cortical granule classes and meiotic stages was affected by G- administration (P<0.05) but not by G+ administration. The proportion of oocytes that cleaved to two- and four-cell stage embryos (44 h postfertilization) was lower in both G+ and G- groups than in controls (P<0.05). Blastocyst formation rate (7-8 days postfertilization) was lower in the G- group (P<0.05) and numerically lower in the G+ group compared with their uninfected counterparts. The total cell number in blastocysts did not differ among groups; however, the apoptotic index was higher in the G+ group (P<0.05), but not in the G- group, relative to controls. Examining mRNA relative abundance in oocytes and early embryos revealed mastitis-induced alterations in PTGS2 (COX2), POU5F1, and HSF1 but not in SLC2A1 (GLUT1) or GDF9. Results indicate a differential disruptive effect of mastitis induced by G- and G+ on oocyte developmental competence in association with alterations in maternal gene expression.


Assuntos
Lactação/fisiologia , Mastite/fisiopatologia , Oócitos/fisiologia , Animais , Blastocisto/metabolismo , Bovinos , Escherichia coli , Feminino , Expressão Gênica , Lactação/metabolismo , Mastite/microbiologia , Oócitos/metabolismo , Oócitos/microbiologia , Staphylococcus aureus
10.
J Dairy Sci ; 97(12): 7465-75, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25306276

RESUMO

Reduced conception rate (CR) during the hot summer and subsequent autumn is a well-documented phenomenon. Intensive use of cooling systems can improve summer and autumn reproductive performance, but is unable to increase CR to winter and spring levels. We examined whether combined hormonal treatments--to increase follicular turnover before artificial insemination (AI) and progesterone supplementation post-AI--might improve fertility of cooled cows during the summer and autumn. The experiment was conducted from July to November in 3 commercial herds in Israel and included 707 Holstein cows at 50 to 60 d in milk (DIM). Cows were hormonally treated to induce 2 consecutive 9-d cycles, with GnRH administration followed by PGF2α injection 7 d later, followed by an intravaginal insert containing progesterone on d 5 ± 1 post-AI for 14 d. Both untreated controls (n=376) and treated cows (n=331) were inseminated following estrus, and pregnancy was determined by palpation 42 to 50 d post-AI. First-AI CR data revealed a positive interaction between treatment and cows previously diagnosed with postpartum uterine disease [odds ratio (OR) 2.24]. Interaction between treatment and low body condition score tended to increase the probability of first-AI CR (OR 1.95) and increased pregnancy rate at 90 DIM (OR 2.50) and at 120 DIM (OR 1.77). Low milk production increased the probability of being detected in estrus at the end of synchronization within treated cows (OR 1.67), and interacted with treatment to increase probability of pregnancy at 90 DIM (OR 2.39) relative to control counterparts. It is suggested that when administered with efficient cooling, combined hormonal treatment in specific subgroups of cows, that is, those previously diagnosed with postpartum uterine disease or those with low body condition score or low milk yield might improve fertility during the summer and autumn. Integration of such an approach into reproductive management during the hot seasons might improve treatment efficiency and reduce expenses.


Assuntos
Bovinos/fisiologia , Fertilidade/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Inseminação Artificial/veterinária , Progesterona/farmacologia , Animais , Temperatura Corporal , Indústria de Laticínios/métodos , Dinoprosta/administração & dosagem , Estro/efeitos dos fármacos , Feminino , Fertilidade/fisiologia , Fertilização/efeitos dos fármacos , Temperatura Alta , Leite/citologia , Leite/efeitos dos fármacos , Leite/metabolismo , Período Pós-Parto , Gravidez , Taxa de Gravidez , Reprodução/efeitos dos fármacos , Estações do Ano , Estresse Fisiológico
11.
Reproduction ; 145(5): 479-89, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23630332

RESUMO

Season-induced variation in fatty acid and cholesterol composition in bovine semen has been associated with semen quality. Given the specific roles of the various semen compartments (seminal fluids, sperm head, and sperm tail) in fertilization, we hypothesized that environmental-stress-induced alterations in the lipid composition of a specific compartment might impair semen quality and sperm function. Semen samples were collected from five mature Holstein-Friesian bulls during the summer (August to September) and winter (December to January). Semen was evaluated by computerized sperm-quality analyzer, calibrated for bulls' semen, and centrifuged to separate the spermatozoa from the seminal fluids. The spermatozoal fraction was sonicated to separate the sperm head and tail compartments. Cold lipid extraction was performed with chloroform:methanol (2:1, vol/vol). Lipids were identified and quantified by gas chromatography. Seasonal variation was found in both physiological and structural parameters. The proportion of spermatozoa defined as morphologically normal was higher in the winter, with higher motility, progressive motility, and velocity relative to summer samples. Lipid composition within fractions varied between seasons with prominent impairment in the tail compartment, characterized by high saturated fatty acid, low polyunsaturated fatty acid, and low cholesterol concentrations during the summer. Given the association between alterations in lipid composition and reduced sperm motility and velocity during the summer, it is suggested that lipid composition might serve to predict sperm quality.


Assuntos
Doenças dos Bovinos/metabolismo , Infertilidade Masculina/veterinária , Metabolismo dos Lipídeos , Sêmen/metabolismo , Estresse Fisiológico , Animais , Animais Endogâmicos , Astenozoospermia/etiologia , Astenozoospermia/metabolismo , Astenozoospermia/patologia , Astenozoospermia/veterinária , Bovinos , Doenças dos Bovinos/etiologia , Doenças dos Bovinos/patologia , Forma Celular , Colesterol/análise , Colesterol/metabolismo , Ácidos Graxos/análise , Ácidos Graxos/metabolismo , Ionização de Chama/veterinária , Infertilidade Masculina/etiologia , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Israel , Masculino , Estações do Ano , Sêmen/citologia , Análise do Sêmen/veterinária , Cabeça do Espermatozoide/metabolismo , Cabeça do Espermatozoide/patologia , Cauda do Espermatozoide/metabolismo , Cauda do Espermatozoide/patologia
12.
J Dairy Sci ; 96(10): 6499-505, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23957998

RESUMO

We examined the effects of naturally occurring mastitis on bovine oocyte developmental competence in vitro. Specifically, we investigated the effects of intramammary infection on the ovarian pool of oocytes (i.e., follicle-enclosed oocytes) and their ability to undergo in vitro maturation, fertilization, and further development to the blastocyst stage. Culled Holstein cows (n=50) from 9 commercial dairy farms in Israel were allotted to 3 groups according to somatic cell count (SCC) records of the last 3 monthly milk tests as well as of quarter samples collected before slaughter: (1) low SCC (n=7), (2) medium SCC (n=16), or (3) high SCC (n=27). Means of SCC values differed among low-, medium-, and high-SCC groups: 148,000, 311,000 and 1,813,000 cell/mL milk, respectively. Milk yield and days in milk did not differ among the 3 groups. Bacterial isolates included coagulase-negative staphylococci, Escherichia coli, Streptococcus dysgalactiae, or no bacteria found. Ovaries were collected at the abattoir and brought to the laboratory. Cumulus oocyte complexes were recovered separately from each cow and subjected individually to in vitro maturation and fertilization, followed by 8d in culture. The number of aspirated oocytes did not differ among groups, with a range of 17 to 21 oocytes per cow. The proportion of oocytes that cleaved into 2- to 4-cell-stage embryos (86.1 ± 3.4%) did not differ among groups. In contrast, mean percentages of embryos developed to the blastocyst stage on d 7 and 8 after fertilization were less in both medium- and-high SCC groups than in the low-SCC group (5.6 ± 2.3 and 4.1 ± 1.8 vs. 18.1 ± 4.6%, respectively). Additional analysis indicated that cleavage and blastocyst-formation rates did not differ among the bacterial types in the low-, medium-, and high-SCC groups. These are the first results to demonstrate that naturally occurring mastitis disrupts the developmental competence of the ovarian pool of oocytes, (i.e., oocytes at the germinal vesicle stage). The disruption was associated with elevation of SCC rather than bacterial type. The results may provide a partial explanation for the low fertility of cows that have contracted mastitic pathogens before insemination.


Assuntos
Blastocisto/fisiologia , Mastite Bovina/microbiologia , Mastite Bovina/fisiopatologia , Oócitos/fisiologia , Folículo Ovariano/embriologia , Animais , Blastocisto/microbiologia , Bovinos , Contagem de Células/veterinária , Feminino , Técnicas In Vitro , Leite/citologia , Oócitos/microbiologia , Folículo Ovariano/microbiologia
13.
BJA Open ; 5: 100116, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37587996

RESUMO

Background: The volatile anaesthetic sevoflurane protects cardiac tissue from reoxygenation/reperfusion. Mitochondria play an essential role in conditioning. We aimed to investigate how sevoflurane and its primary metabolite hexafluoroisopropanol (HFIP) affect necrosis, apoptosis, and reactive oxygen species formation in cardiomyocytes upon hypoxia/reoxygenation injury. Moreover, we aimed to describe the similarities in the mode of action in a mitochondrial bioenergetics analysis. Methods: Murine cardiomyocytes were exposed to hypoxia (0.2% O2 for 6 h), followed by reoxygenation (air with 5% CO2 for 2 h) in the presence or absence sevoflurane 2.2% or HFIP 4 mM. Lactate dehydrogenase (LDH) release (necrosis), caspase activation (apoptosis), reactive oxygen species, mitochondrial membrane potential, and mitochondrial function (Seahorse XF analyser) were measured. Results: Hypoxia/reoxygenation increased cell death by 44% (+31 to +55%, P<0.001). Reoxygenation in the presence of sevoflurane 2.2% or HFIP 4 mM increased LDH release only by +18% (+6 to +30%) and 20% (+7 to +32%), respectively. Apoptosis and reactive oxygen species formation were attenuated by sevoflurane and HFIP. Mitochondrial bioenergetics analysis of the two substances was profoundly different. Sevoflurane did not influence oxygen consumption rate (OCR) or extracellular acidification rate (ECAR), whereas HFIP reduced OCR and increased ECAR, an effect similar to oligomycin, an adenosine triphosphate (ATP) synthase inhibitor. When blocking the metabolism of sevoflurane into HFIP, protective effects of sevoflurane - but not of HFIP - on LDH release and caspase were mitigated. Conclusion: Together, our data suggest that sevoflurane metabolism into HFIP plays an essential role in cardiomyocyte postconditioning after hypoxia/reoxygenation injury.

14.
Clin Exp Immunol ; 169(2): 119-28, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22774986

RESUMO

Dexamethasone has been found to reduce the incidence of high-altitude pulmonary oedema. Mechanisms explaining this effect still remain unclear. We assessed the effect of dexamethasone using established cell lines, including rat alveolar epithelial cells (AEC), pulmonary artery endothelial cells (RPAEC) and alveolar macrophages (MAC), in an environment of low oxygen, simulating a condition of alveolar hypoxia as found at high altitude. Inflammatory mediators and ion transporter expression were quantified. Based on earlier results, we hypothesized that hypoxic conditions trigger inflammation. AEC, RPAEC and MAC, pre-incubated for 1 h with or without dexamethasone (10(-7) mol/l), were subsequently exposed to mild hypoxia (5% O(2), or normoxia as control) for 24 h. mRNA and protein levels of cytokine-induced neutrophil chemoattractant-1, monocyte chemoattractant protein-1 and interleukin-6 were analysed. mRNA expression and functional activity of the apical epithelial sodium channel and basolateral Na(+)/K(+)-ATPase were determined using radioactive marker ions. In all three types of pulmonary cells hypoxic conditions led to an attenuated secretion of inflammatory mediators, which was even more pronounced in dexamethasone pretreated samples. Function of Na(+)/K(+)-ATPase was not significantly influenced by hypoxia or dexamethasone, while activity of epithelial sodium channels was decreased under hypoxic conditions. When pre-incubated with dexamethasone, however, transporter activity was partially maintained. These findings illustrate that long-term hypoxia does not trigger an inflammatory response. The ion transport across apical epithelial sodium channels under hypoxic conditions is ameliorated in cells treated with dexamethasone.


Assuntos
Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Dexametasona/farmacologia , Inflamação/metabolismo , Canais Iônicos/metabolismo , Células Epiteliais Alveolares/imunologia , Animais , Hipóxia Celular , Sobrevivência Celular/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Ratos
15.
Cell Biol Toxicol ; 28(6): 383-96, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22956148

RESUMO

In the last decade, potential exposure of humans and animals to industrial chemicals and pesticides has been a growing concern. In the present study, di-(2-ethylhexyl) phthalate (DEHP) and mono-(2-ethylhexyl) phthalate (MEHP) were used to model the effects of endocrine-disrupting compounds and their risk in relation to early embryonic losses. Exposure of cumulus oocyte complexes during maturation to 50 µM MEHP reduced the proportion of oocytes that underwent nuclear maturation (p < 0.05) and increased the proportion of apoptotic oocytes (p < 0.05). Furthermore, phthalates reduced cleavage rate in the MEHP-treated group (p < 0.05) and the proportion of embryos developing to the blastocyst stage in both DEHP- and MEHP-treated groups (p < 0.05). The total cell count for blastocysts developing from MEHP-treated oocytes was lower than in controls (p < 0.05). Exposure of oocytes to MEHP during maturation reduced (p < 0.05) the expression of ASAH1 (an anti-apoptotic factor), CCNA2 (involved in cell cycle control), and POU5F1 (responsible for pluripotency) in matured oocytes. Furthermore, the reduced mRNA expression of POU5F1 and ASAH1 lasted into two-cell stage embryos (p < 0.05). Phthalate-induced alterations in POU5F1, ASAH1, and CCNA2 expression might explain in part the reduced developmental competence of MEHP-treated oocytes.


Assuntos
Fase de Clivagem do Zigoto/efeitos dos fármacos , Dietilexilftalato/análogos & derivados , Dietilexilftalato/toxicidade , Embrião de Mamíferos/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Oócitos/efeitos dos fármacos , Ceramidase Ácida/biossíntese , Ceramidase Ácida/genética , Animais , Blastocisto/efeitos dos fármacos , Bovinos , Núcleo Celular/efeitos dos fármacos , Ciclina A2/biossíntese , Fragmentação do DNA/efeitos dos fármacos , Embrião de Mamíferos/fisiologia , Fator 3 de Transcrição de Octâmero/biossíntese , Fator 3 de Transcrição de Octâmero/genética , Oócitos/citologia , Oócitos/fisiologia , Oogênese/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
J Dairy Sci ; 95(6): 3092-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22612945

RESUMO

Reduced fertility of dairy cows during periods of elevated temperature, humidity, or both might be associated with low plasma progesterone concentration. Alleviation of thermal stress by efficient cooling is a prerequisite for improving fertility by hormonal treatment. We examined whether insertion of a controlled intravaginal drug-releasing (CIDR) insert containing progesterone following artificial insemination (AI) would improve summer conception rate. Control (n = 195) and treated (CIDR; n=165) cows, yielding on average 42.3 kg milk/d, were inseminated following estrus detection during the summer (July to October) in 2 commercial dairy herds in Israel. Mean maximal air temperature and relative humidity during the study were 30.2°C and 86%, respectively. All experimental cows were efficiently cooled throughout the study, as confirmed by measuring the body temperature of random cows. Treated cows received a CIDR insert on d 5 ± 1 post-AI for 13 d and pregnancy was confirmed by palpation 45 d post-AI. Plasma progesterone concentration in treated cows was elevated by approximately 1.5 ng/mL. Multiple logistic regressions were used to analyze conception rate. Treatment did not alter the overall conception rate; however, probability of conception increased in CIDR-treated cows with low body condition score (BCS) compared with their control counterparts (53 vs. 27%, respectively). A pronounced increase in probability of conception was recorded in CIDR-treated cows exhibiting both low BCS and postpartum reproductive disorders, compared with their control counterparts (58 vs. 14%, respectively). Exogenous progesterone supplementation on d 5 post-AI for 13 d improves summer fertility of subpopulations of cows exhibiting low BCS and postpartum reproductive disorders. Reproductive management based on specific hormonal treatment of designated subgroups of cows known to derive beneficial effects from it might improve treatment efficiency and reduce expenses.


Assuntos
Fertilidade/efeitos dos fármacos , Progesterona/farmacologia , Administração Intravaginal , Animais , Temperatura Corporal , Bovinos/fisiologia , Preparações de Ação Retardada , Feminino , Fertilidade/fisiologia , Fertilização/efeitos dos fármacos , Fertilização/fisiologia , Gravidez , Progesterona/administração & dosagem , Progesterona/sangue , Estações do Ano
17.
J Dairy Sci ; 95(4): 1729-37, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22459821

RESUMO

Ovarian follicular cysts and persistent follicles are follicular pathologies involved in reduced fertility of dairy cows. Two separate experiments were performed on high-yielding Holstein cows to characterize ovarian cyclicity and evaluate the developmental dynamics of follicle pathologies postpartum. In experiment 1, 58 cows were monitored by ultrasonography twice weekly from d 18±1 to 69±2 postpartum. First ovulation occurred 38±3, 27±2, 20±1, and 25±3 d postpartum in cows with 1 cycle (n=11), 2 cycles (n=21), 3 cycles (n=13), and 4 cycles (n=7), respectively. Follicular pathologies were developed in cows that were either acyclic (n=6) or had 1 or 2 cycles, but not in cows with more than 2 cycles. In experiment 2, 47 cows were monitored twice weekly from 10 d postpartum to second ovulation. Follicles ≥17 mm in diameter in 2 consecutive scans were aspirated, and concentrations of various hormones were measured. Cows were defined as cyclic (n=30; 64%) or with the potential to develop follicular pathology (n=17; 36%). Aspirated follicles (n=27) were classified into 3 main groups based on follicular growth rate, follicular diameter, and ovarian activity before and after follicular aspiration. Dominant follicles (n=4) were defined as large follicles (20 mm in diameter) with growth rate ≤1 mm/d and normal ovarian activity. Persistent follicles (n=6) had the same growth rate and diameter as the dominant follicles, but persisted at the same diameter for ≥10 d. Ovarian cysts (n=17) were defined as the largest follicular structures (19 to 32 mm in diameter), with abnormal growth rate (>1 mm/d) and abnormal ovarian activity. Single or turnover cysts did not differ in their growth parameters and were therefore combined and further classified according to follicular-fluid hormone concentrations. Estradiol-dominant cysts (n=7) were characterized by normal estradiol (284 to 659 ng/mL) and progesterone (20 to 113 ng/mL) concentrations, similar to those of the dominant follicle (554 to 993 ng/mL and 44 to 106 ng/mL, respectively). Progesterone-dominant cysts (n=5) were characterized by low estradiol (0.06 to 330 ng/mL) and high progesterone (586 to 3,288 ng/mL) concentrations. Low-steroidogenic active cysts (n=5) were characterized by low concentrations of both estradiol (23 to 61 ng/mL) and progesterone (17 to 205 ng/mL). Characterization of spontaneously forming cysts might enable definition of the formation of ovarian follicular pathologies in postpartum cows.


Assuntos
Doenças dos Bovinos/patologia , Líquido Folicular/química , Hormônios/análise , Cistos Ovarianos/veterinária , Folículo Ovariano/patologia , Transtornos Puerperais/veterinária , Animais , Bovinos , Doenças dos Bovinos/diagnóstico por imagem , Doenças dos Bovinos/etiologia , Estradiol/análise , Feminino , Cistos Ovarianos/etiologia , Cistos Ovarianos/patologia , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/fisiopatologia , Progesterona/análise , Progesterona/sangue , Transtornos Puerperais/etiologia , Transtornos Puerperais/patologia , Ultrassonografia
18.
Heliyon ; 8(3): e09025, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35846481

RESUMO

Primary culture of mammary epithelial cells (MEC) was exposed to ethyl-acetate, chloroform and hexane extracts of Pistacia lentiscus (lentisk). The hexane extract contained mainly ethyl gallate whereas the chloroform extract contained mainly ethyl-gallate with smaller amount of gallic acid, and the ethyl-acetate extract contained mainly rutin, gallic acid and myricetin. Ethyl acetate extract increased secretion of protein and fat and improved mitochondrial activity. The enhancing effect on protein production was attributed to myricetin, one of the polyphenols in the ethyl-acetate extract whereas gallic acid did not affect protein production or secretion. Interestingly, exposure to the isolated polyphenols did not improve mitochondrial productivity and activity as effectively as exposure to the complete plant extract. The results indicated that polyphenols improve production of milk constituents by MEC, through different modes of action for different polyphenols suggesting an additive or even synergistic effect on production traits of mammary cells.

19.
Am J Respir Cell Mol Biol ; 45(3): 617-24, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21239603

RESUMO

Volatile anesthetics are known to attenuate inflammatory response and tissue damage markers in acute organ injury. It is unclear whether these beneficial effects of volatile anesthetics are mediated by the ether basic structure or by characteristics of their halogenations. We describe in an in vitro model of acute inflammation in pulmonary cells that halogenation (fluorinated carbon groups) is responsible for the immunomodulatory effects. The inflammatory response after coexposure to endotoxin and sevoflurane, diethyl-ether, or various water-soluble molecules carrying trifluorinated carbon (CF(3)) groups was evaluated in pulmonary epithelial and endothelial cells and in neutrophils. In epithelial and endothelial cells, expression of inflammatory mediators to LPS stimulation was dose-dependently decreased upon exposure to sevoflurane and other molecules with CF(3) groups. This was not observed for diethyl-ether or structure-similar nonfluorinated molecules. In neutrophils, chemotactic activity, as well as expression of surface CD11b and CD62L, was positively modified by molecules carrying CF(3) groups. Cytotoxicity could be excluded. These findings for the first time reveal in an in vitro model of acute inflammation that the immunomodulatory effects are not limited to volatile anesthetics but are associated with a much broader class of CF(3) group-containing molecules. The immunomodulatory effects could now be provided in a hydrophilic, injectable formulation for the treatment of patients suffering from acute organ injury, such as acute lung injury, in environments not suitable for volatile anesthetics.


Assuntos
Anestésicos/farmacologia , Flúor/farmacologia , Fatores Imunológicos/imunologia , Animais , Aorta/citologia , Carbono/química , Caspase 3/metabolismo , Relação Dose-Resposta a Droga , Células Endoteliais/citologia , Células Epiteliais/citologia , Escherichia coli/metabolismo , Halogênios/química , Humanos , Inflamação , Lipopolissacarídeos/metabolismo , Éteres Metílicos/farmacologia , Microcirculação , Neutrófilos/citologia , Ratos , Sevoflurano
20.
J Dairy Sci ; 94(5): 2393-402, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21524529

RESUMO

Reduced conception rate during the hot summer and subsequent autumn is a well-documented phenomenon. Evaporative cooling systems greatly increase milk production but only slightly improve reproductive performance; hence, additional approaches to improving fertility during the hot season are required. The purpose of the present study was to examine whether the combination of an efficient cooling system and hormonal manipulation (GnRH+PGF(2α)) might improve fertility during the summer and autumn. The experiment was conducted from July to December in 2 commercial herds in Israel and included 382 healthy Holstein cows. Cows (50 to 60 d in milk) were hormonally treated to induce 3 consecutive 9-d follicular waves, with GnRH administration followed by PGF(2α) injection 7 d later. Both control (n=187) and treated (n=195) cows were inseminated following estrus, and pregnancy was determined by palpation 45 d post-insemination. Data revealed an interaction between treatment and primiparous cows, reflected by a 16% increase in conception rate [odds ratio (OR) 2.32, 95% confidence interval (CI): 0.96-5.61] and 14% increase in pregnancy rate at 120 d in milk (OR 3.16, 95% CI: 0.93-10.47). Interaction between treatment and high body condition score was reflected by a 14% increase in pregnancy rate at 90 d in milk (OR 3.02, 95% CI: 1.14-7.96). About 60% of the treated cows expressed estrus at the expected time (normal response within 5 d following the third PGF(2α) injection); the remaining 40% that manifested estrus later (late response) had higher milk yield and lower body condition score. Additional analyses indicated that treatment interacted with normal response to raise conception rates and pregnancy rates of primiparous cows and cows with high body condition score. On the other hand, treatment by late-response interaction lowered conception rate during the summer. Implementation of such hormonal treatment in combination with an efficient cooling system may improve reproductive performance of dairy cows during the summer and subsequent autumn.


Assuntos
Regulação da Temperatura Corporal/fisiologia , Bovinos/fisiologia , Dinoprosta/administração & dosagem , Fertilidade/fisiologia , Hormônio Liberador de Gonadotropina/administração & dosagem , Folículo Ovariano/efeitos dos fármacos , Estações do Ano , Ar Condicionado , Animais , Indústria de Laticínios/métodos , Feminino , Israel , Lactação/fisiologia , Folículo Ovariano/fisiologia , Gravidez , Taxa de Gravidez
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