Effects of Ewe’s Diet Supplementation with Polyunsaturated Fatty Acids on Meat Lipid Profile of Suckling Lambs

[EN] Polyunsaturated fatty acid (PUFA) deposition in lambs’ muscles could be influenced by their mothers’ diet. The aim was to study the profile of fatty acids in the muscle of lambs from ewes supplemented with different sources of PUFA to achieve a healthier meat for the consumer. On day 100 of gestation, pregnant ewes grazed on natural grass were divided into three groups (n = 20) and supplemented with PUFA: Group A: 700 g of a ration rich in PUFA, Group B: 700 g of a ration for sheep + 20 mL of fish oil and Group C: 700 g of the same ration. After parturition, each group was subdivided: ten ewes continued with the same diet until the end of lactation; the other ten were fed only natural grass. The values of n-3 and n-6 PUFA and alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), linoleic acid (LA) and arachidonic acid (AA) were analyzed in Longissimus lumborum muscles of lambs at 90 and 120 days of life. The feeding of ewes during lactation favorably influenced the lipid profile of the lamb muscle, increasing the concentration of n-3 and n-6 PUFA, ALA, LA, AA, DHA and EPA. The supplementation of ewes with fish oil and/or a ration rich in PUFA improved the LA/ALA ratio in lambs’ meatSIThis research was funded by the CSIC-UdelaR (Comisión Sectorial de Investigación Científica, Universidad de la República), project “Metabolic, behavioral parameters and concentration of fatty acids in carcass of lambs born to mothers supplemented with long-chain polyunsaturated fatty acids”. 201

Lactococcus lactis autóctono: evaluación del efecto antilisterial y de propiedades sensoriales en quesos tipo Cuartirolo = Autochthonous Lactococcus lactis strain: evaluation of antilisterial activity and sensory properties in Cuartirolo cheese

Las bacterias ácido lácticas (BAL) forman parte de la microbiota natural láctea y son componentes de muchos cultivos iniciadores para elaboración quesera. Las BAL pueden presentar actividad antimicrobiana por la producción de diferentes sustancias, entre ellas, péptidos, denominados bacteriocinas, que pueden ser producidas in situ en la tina quesera. Algunas bacteriocinas incluyen en su espectro de acción Listeria monocytogenes, patógeno asociado a alimentos que representa un riesgo para la salud pública. Este trabajo propuso evaluar el efecto antilisterial de una BAL autóctona en quesos tipo Cuartirolo y la modificación de las propiedades sensoriales por su aplicación. El diseño experimental incluyó dos tratamientos (con o sin Lactococcus lactis autóctono). Los quesos de ambos tratamientos se dividieron en dos, el primer lote se inoculó con Listeria innocua y se realizó recuento a las 2 horas y a los 7 y 14 días. El restante se evaluó sensorialmente mediante una técnica sensorial descriptiva. Se comprobó que Lactococcus lactis GU967439 tiene actividad antagonista in vitro contra Listeria innocua y Listeria monocytogenes. También existieron diferencias significativas (p< 0,05) entre los tratamientos en el recuento de Listeria innocua en las muestras de quesos evaluadas. A excepción del sabor salado, las propiedades sensoriales no mostraron diferencias significativas entre tratamientos

Poly(ADP-ribosylation) is present in murine sciatic nerve fibers and is altered in a Charcot-Marie-Tooth-1E neurodegenerative model

Background. Poly-ADP-ribose (PAR) is a polymer synthesized by poly-ADP-ribose polymerases (PARPs) as a postranslational protein modification and catabolized mainly by poly-ADP-ribose glycohydrolase (PARG). In spite of the existence of cytoplasmic PARPs and PARG, research has been focused on nuclear PARPs and PAR, demonstrating roles in the maintenance of chromatin architecture and the participation in DNA damage responses and transcriptional regulation. We have recently detected non-nuclear PAR structurally and functionally associated to the E-cadherin rich zonula adherens and the actin cytoskeleton of VERO epithelial cells. Myelinating Schwann cells (SC) are stabilized by E-cadherin rich autotypic adherens junctions (AJ). We wondered whether PAR would map to these regions. Besides, we have demonstrated an altered microfilament pattern in peripheral nerves of Trembler-J (Tr-J) model of CMT1-E. We hypothesized that cytoplasmic PAR would accompany such modified F-actin pattern. Methods. Wild-type (WT) and Tr-J mice sciatic nerves cryosections were subjected to immunohistofluorescence with anti-PAR antibodies (including antibody validation), F-actin detection with a phalloidin probe and DAPI/DNA counterstaining. Confocal image stacks were subjected to a colocalization highlighter and to semi-quantitative image analysis. Results. We have shown for the first time the presence of PAR in sciatic nerves. Cytoplasmic PAR colocalized with F-actin at non-compact myelin regions in WT nerves. Moreover, in Tr-J, cytoplasmic PAR was augmented in close correlation with actin. In addition, nuclear PAR was detected in WT SC and was moderately increased in Tr-J SC. Discussion. The presence of PAR associated to non-compact myelin regions (which constitute E-cadherin rich autotypic AJ /actin anchorage regions) and the co-alterations experienced by PAR and the actin cytoskeleton in epithelium and nerves, suggest that PAR may be a constitutive component of AJ /actin anchorage regions. Is PAR stabilizing the AJ -actin complexes? This question has strong implications in structural cell biology and cell signaling networks. Moreover, if PAR played a stabilizing role, such stabilization could participate in the physiological control of axonal branching. PARP and PAR alterations exist in several neurodegenerative pathologies including Alzheimer's, Parkinson's and Hungtington's diseases. Conversely, PARP inhibition decreases PAR and promotes neurite outgrowth in cortical neurons in vitro. Coherently, the PARP inhibitor XAV939 improves myelination in vitro, ex vivo and in vivo. Until now such results have been interpreted in terms of nuclear PARP activity. Our results indicate for the first time the presence of PARylation in peripheral nerve fibers, in a healthy environment. Besides, we have evidenced a PARylation increase in Tr-J, suggesting that the involvement of cytoplasmic PARPs and PARylation in normal and neurodegenerative conditions should be re-evaluated

Subclinical ovine gestational toxaemia at parturition: Influence on determinant variables in lamb survival

[EN] - The objective of this study was to determine the impact of metabolic changes occurring in induced subclinical gestation toxaemia in ewes on metabolic parameters and vigour in the first 72 h of their lambs’ life. Fifty-one adult Corriedale ewes of known gestation date and fed on a natural pasture were randomly divided into four groups at day 145 of gestation. Group A (ewes with single pregnancies) and group C (ewes with twin pregnancies) were fed on a natural pasture throughout the trial; group B (ewes with single pregnancies) and group D (ewes with twin pregnancies) were subjected to 75% feed restriction for three days until they reached glycaemia and β-hydroxybutyrate (BHB) values indicative of subclinical gestational toxaemia. The birth-to-first station and birth-to-first suckling times of the born lambs were studied. Within the first hour after parturition and at 24, 48, and 72 h, glycaemia and BHB concentrations were determined in the blood of lambs, and body temperature and body weight were assessed at the same time. Relative weight gain at 72 h of age was calculated for all lambs. The BHB concentration determined at all times studied showed no difference among the groups. Subclinical gestation toxaemia induced in ewes subjected to feed restriction causes a decrease in the glycaemia of their lambs in the first hour of life; however, it does not cause an increase in ketone bodies. The metabolic changes induced in the mothers do not have negative effects on the vigour of the lambs at birth, as the weight, temperature, and the time it took for lambs to stand and suckle are not affected. However, they have a negative effect on relative weight gain in the critical period of the first 72 h of life.This work was made possible thanks to funding from the Comisión Sectorial de Investigación Científica (CSIC) of the Universidad de la República. We would also like to thank the director of Experimental Field Nº2, Dr. Elena de Torres, as well as the staff working at this research facility of the Facultad de Veterinaria, especially Mr. Gustavo Cazard, for their support. We also thank the training program of the Agencia Nacional de Investigación e Innovación (ANII), for having provided a Master’s scholarship to carry out this work

Lactococcus lactis autóctono: evaluación del efecto antilisterial y de propiedades sensoriales en quesos tipo Cuartirolo

Acid lactic bacteria (LAB) are part of milk natural microbiota and are components of many starter cultures used&nbsp;in cheese making. The LAB may exhibit antimicrobial activity, based on the production of various substances,&nbsp;among them, peptides called bacteriocins that can be produced in situ in cheese making.&nbsp;Some bacteriocins include in their spectrum of action Listeria monocytogenes, pathogen associated to food that&nbsp;represents a risk to public health. The aim of this study was to evaluate antilisterial effect of an autochthonous LAB&nbsp;in Cuartirolo cheese and determine if their use altered the sensory properties of that cheese. This experimental&nbsp;design included two treatments: with and without autochthonous Lactococcus lactis. Cheese was divided into&nbsp;two groups, the first one was inoculated with Listeria innocua, making the quantification two hours, seven days&nbsp;and fourteen days later. Regarding sensory evaluation a descriptive sensory technique was used. In this study,&nbsp;Lactococcus lactis GU96743 had an antagonic activity in vitro against Listeria innocua and Listeria monocytogenes. There were also significant differences (p&lt;0,05) between the treatments in quantification of Listeria innocua&nbsp;in the samples of cheese evaluated. Except for the salty flavor, the sensorial properties did not show differences&nbsp;between treatments.Las bacterias ácido lácticas (BAL) forman parte de la microbiota natural láctea y son componentes de muchos&nbsp;cultivos iniciadores para elaboración quesera. Las BAL pueden presentar actividad antimicrobiana por la producción de diferentes sustancias, entre ellas, péptidos, denominados bacteriocinas, que pueden ser producidas in situ&nbsp;en la tina quesera. Algunas bacteriocinas incluyen en su espectro de acción Listeria monocytogenes, patógeno&nbsp;asociado a alimentos que representa un riesgo para la salud pública. Este trabajo propuso evaluar el efecto antilisterial de una BAL autóctona en quesos tipo Cuartirolo y la modificación de las propiedades sensoriales por su&nbsp;aplicación. El diseño experimental incluyó dos tratamientos (con o sin Lactococcus lactis autóctono). Los quesosde ambos tratamientos se dividieron en dos, el primer lote se inoculó con Listeria innocua y se realizó recuento a&nbsp;las 2 horas y a los 7 y 14 días. El restante se evaluó sensorialmente mediante una técnica sensorial descriptiva. Se&nbsp;comprobó que Lactococcus lactis GU967439 tiene actividad antagonista in vitro contra Listeria innocua y Listeria&nbsp;monocytogenes. También existieron diferencias significativas (p&lt; 0,05) entre los tratamientos en el recuento de&nbsp;Listeria innocua en las muestras de quesos evaluadas. A excepción del sabor salado, las propiedades sensoriales&nbsp;no mostraron diferencias significativas entre tratamientos. &nbsp

Subclinical ovine gestational toxaemia at parturition: influence on determinant variables in lamb survival

The objective of this study was to determine the impact of metabolic changes occurring in induced subclinical gestation toxaemia in ewes on metabolic parameters and vigour in the first 72 h of their lambs’ life. Fifty-one adult Corriedale ewes of known gestation date and fed on a natural pasture were randomly divided into four groups at day 145 of gestation. Group A (ewes with single pregnancies) and group C (ewes with twin pregnancies) were fed on a natural pasture throughout the trial; group B (ewes with single pregnancies) and group D (ewes with twin pregnancies) were subjected to 75% feed restriction for three days until they reached glycaemia and β-hydroxybutyrate (BHB) values indicative of subclinical gestational toxaemia. The birth-to-first station and birth-to-first suckling times of the born lambs were studied. Within the first hour after parturition and at 24, 48, and 72 h, glycaemia and BHB concentrations were determined in the blood of lambs, and body temperature and body weight were assessed at the same time. Relative weight gain at 72 h of age was calculated for all lambs. The BHB concentration determined at all times studied showed no difference among the groups. Subclinical gestation toxaemia induced in ewes subjected to feed restriction causes a decrease in the glycaemia of their lambs in the first hour of life; however, it does not cause an increase in ketone bodies. The metabolic changes induced in the mothers do not have negative effects on the vigour of the lambs at birth, as the weight, temperature, and the time it took for lambs to stand and suckle are not affected. However, they have a negative effect on relative weight gain in the critical period of the first 72 h of life

Myosin-Va-dependent cell-to-cell transfer of RNA from Schwann cells to axons.

To better understand the role of protein synthesis in axons, we have identified the source of a portion of axonal RNA. We show that proximal segments of transected sciatic nerves accumulate newly-synthesized RNA in axons. This RNA is synthesized in Schwann cells because the RNA was labeled in the complete absence of neuronal cell bodies both in vitro and in vivo. We also demonstrate that the transfer is prevented by disruption of actin and that it fails to occur in the absence of myosin-Va. Our results demonstrate cell-to-cell transfer of RNA and identify part of the mechanism required for transfer. The induction of cell-to-cell RNA transfer by injury suggests that interventions following injury or degeneration, particularly gene therapy, may be accomplished by applying them to nearby glial cells (or implanted stem cells) at the site of injury to promote regeneration

Myosin-Va function is required for transfer of RNA from Schwann cells to axons.

<p>Longitudinal 10-µm sections of transected sciatic nerves from null (d-l) <i>Myo5a</i> mutant mice have reduced axoplasmic levels of newly synthesized RNA. <b>A and C</b>, null mutant; <b>B and D</b>, wild-type control. RNA labeled by BrU is shown in green, the paranodal marker Caspr in red. Panels C and D show higher magnification views of boxed regions in panels A and B respectively. Arrows, nodes of Ranvier; arrowheads, bands of Cajal (compare to arrows in Fig. 6). Micrographs are single optical sections from Z-stacks imaged with a laser scanning confocal microscope. Bar = 5 µm. <b>E</b>, linescan quantitation of abundance of BrU-labeled RNA across fibers from d-l mutant and wild-type control mice. Edges are the outer wraps of Schwann cells; center approximates the location of the axon. Intensity measurements were normalized to the mean of each linescan. Bars represent standard deviations. <b>F</b>, Absolute BrU fluorescence intensities in edges (as shown in <b>E</b>, 4 bins at each end combined; n = 160) and centers (10 central bins combined; n = 200). Error bars represent standard errors.</p