Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2009. / Härtill 5 uppsatser.

Conjugated linoleic acid (CLA) is produced in the rumen by isomerization of linoleic acid and has been shown to be anticarcinogenic. The objective of this study was to determine the effects of feeding dietary CLA to pre-ruminant lambs or linoleic acid-rich safflower oil to weaned ruminating lambs. Fat content, CLA content and fatty acid (FA) composition of diaphragm, leg, rib, subcutaneous (SC) adipose and liver tissues were determined. The triacylglycerol (TAG) fractions of the total lipid (TL) from the diaphragm, rib and SC adipose tissues were analyzed for FA composition and FA positional distribution. The phospholipid (PL) fractions of the TL were analyzed for FA composition. The positional (PL) fractions of the TL were analyzed for FA composition. The positional distribution of FAs of liver PL was determined. Tissue fat content was affected by diet only in SC adipose tissue. Dietary supplementation with safflower oil increased the fat content of the subcutaneous adipose tissue whereas CLA supplementation resulted in decreased (P<0.05) fat content. Dietary supplementation with safflower oil increased (P<0.05) the CLA content of tissues by more than 200% whereas dietary supplementation with CLA did not affect CLA content. Positional distribution analysis indicated that CLA tends was localized to the sn-1/3 positions of TAG and the sn-2 position of the liver PL. / xiii, 74 leaves : ill. ; 28 cm.

No description available.

The putative peroxisome proliferator-activated receptor (PPAR) α ligand, conjugated linoleic acid (CLA) induced cytoplasmic lipid droplet (LD) formation in H4IIE rat hepatoma cells. Currently, the mechanism(s) by which CLA isomers affects hepatic LD formation is unclear. We have investigated the role of PPARα and fatty acid (FA) activation in the regulation of hepatic LD formation induced by CLA isomers [cis-9,trans-11 (c9,t11), trans-10,cis-12 (t10,c12)] and linoleic acid (LA) in an in vitro model of lipid accumulation. Dose response of c9,t11 and t10,c12 CLA isomers as well as LA in quiescent H4IIE cells was assessed by Oil Red O staining and subsequent quantification after 24 hours. LD formation was induced by the CLA isomers similar to LA in a dose-dependent manner. However, treatment with the acyl CoA synthetase (ACS) inhibitor, triacsin C, resulted in significantly reduced LD formation. A similar reduction in lipid accumulation was observed with the PPARα activator, Wy14643. Furthermore, CLA isomers promoted H4IIE viability at 60 µM but decreased viability at a higher dose of 180 µM. To further understand the role of PPARα in hepatic steatosis, we studied the level and phosphorylation of PPARα in livers of male lean and fa/fa Zucker rats fed either a control diet or fa/fa Zucker rats fed a CLA isomer (0.4% wt/wt c9,t11 or 0.4% wt/wt t10,c12) diet for 8 weeks. Immunoblotting results showed that only the t10,c12 CLA isomer significantly reduced phospho-PPARα S21 compared to the lean control (ln Ctl) and it was associated with a significant increase in the phosphorylation of p38 mitogen activated protein kinase (MAPK).These changes were not observed with the c9,t11 CLA isomer. Taken together, we have shown that CLA isomers directly induce LD formation in quiescent H4IIEs by activation of the lipid storage pathway which was significantly reduced by triacsin C or Wy14643. Also, we demonstrate for the first time that only the t10,c12 CLA isomer significantly reduced PPARα phosphorylation while it increased p38 MAPK phosphorylation. These results indicate that the anti-steatotic effects of the t10,c12 CLA isomer is associated with changes in PPARα phosphorylation and thereby its activity in a MAPK-independent manner.

Endothelial inflammation is a pivotal early event in the development of atherosclerosis. Long term exposure to cardiovascular risk factors will ultimately exhaust those protective anti-inflammatory factors such as the heme oxygenase (HO) system. The HO system plays a critical role in cellular and tissue self-defense against oxidative stress and inflammation. Caveolae are membrane domains and are particularly abundant in endothelial cells, where they are believed to play a major role in the regulation of endothelial vesicular trafficking as well as the uptake of lipids and related lipophilic compounds, possibly including bioactive food components such as flavonoids. Research in this dissertation addresses the role of HO-1 and caveolae on dietary flavonoid epigallocatechin gallate (EGCG) mediated protection against pro-inflammatory cytokine tumor necrosis factor-α (TNF-α) and linoleic acid-induced activation of endothelial cells. The data support the hypothesis that EGCG protects against TNF-α-induced monocyte recruitment and adhesion partially through the induction of HO-1 and bilirubin. The observed anti-inflammatory effects of EGCG are mimicked by the HO-1 inducer cobalt protoporphyrin (CoPP) and abolished by HO-1 gene silencing. Nrf2 is the major transcription factor of phase II antioxidant enzymes including HO-1. Results clearly show that EGCG-induced HO-1 expression and subsequent bilirubin productions are dependent on functional Nrf2. EGCG also can down-regulate the base-line level of caveolin-1. Furthermore, silencing of the caveolin-1 gene can markedly down-regulate linoleic acid-induced COX-2 and MCP-1, indicating that caveolae may be a critical platform regulating inflammatory signaling pathways. Similar to EGCG treatment, silencing of caveolin-1 can also result in the activation of Nrf2, up-regulation of HO-1 and bilirubin. This may be one of the mechanisms to explain the protection effect of caveolin-1 gene silencing against endothelial inflammation. Moreover, EGCG rapidly accumulates in caveolae, which is associated with caveolin-1 displacement from the plasma membrane towards the cytosol. Caveolin-1 gene silencing can significantly reduce the uptake of EGCG in endothelial cells within 30 min. These data suggest that caveolae may play a role in the uptake and transport of EGCG in endothelial cells. These studies provide a novel target through which EGCG functions to protect against inflammatory diseases such as atherosclerosis.

The putative peroxisome proliferator-activated receptor (PPAR) α ligand, conjugated linoleic acid (CLA) induced cytoplasmic lipid droplet (LD) formation in H4IIE rat hepatoma cells. Currently, the mechanism(s) by which CLA isomers affects hepatic LD formation is unclear. We have investigated the role of PPARα and fatty acid (FA) activation in the regulation of hepatic LD formation induced by CLA isomers [cis-9,trans-11 (c9,t11), trans-10,cis-12 (t10,c12)] and linoleic acid (LA) in an in vitro model of lipid accumulation. Dose response of c9,t11 and t10,c12 CLA isomers as well as LA in quiescent H4IIE cells was assessed by Oil Red O staining and subsequent quantification after 24 hours. LD formation was induced by the CLA isomers similar to LA in a dose-dependent manner. However, treatment with the acyl CoA synthetase (ACS) inhibitor, triacsin C, resulted in significantly reduced LD formation. A similar reduction in lipid accumulation was observed with the PPARα activator, Wy14643. Furthermore, CLA isomers promoted H4IIE viability at 60 µM but decreased viability at a higher dose of 180 µM. To further understand the role of PPARα in hepatic steatosis, we studied the level and phosphorylation of PPARα in livers of male lean and fa/fa Zucker rats fed either a control diet or fa/fa Zucker rats fed a CLA isomer (0.4% wt/wt c9,t11 or 0.4% wt/wt t10,c12) diet for 8 weeks. Immunoblotting results showed that only the t10,c12 CLA isomer significantly reduced phospho-PPARα S21 compared to the lean control (ln Ctl) and it was associated with a significant increase in the phosphorylation of p38 mitogen activated protein kinase (MAPK).These changes were not observed with the c9,t11 CLA isomer. Taken together, we have shown that CLA isomers directly induce LD formation in quiescent H4IIEs by activation of the lipid storage pathway which was significantly reduced by triacsin C or Wy14643. Also, we demonstrate for the first time that only the t10,c12 CLA isomer significantly reduced PPARα phosphorylation while it increased p38 MAPK phosphorylation. These results indicate that the anti-steatotic effects of the t10,c12 CLA isomer is associated with changes in PPARα phosphorylation and thereby its activity in a MAPK-independent manner.

Made available in DSpace on 2014-06-11T19:30:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-30Bitstream added on 2014-06-13T20:40:32Z : No. of bitstreams: 1 andrade_vxl_dr_jabo.pdf: 876282 bytes, checksum: 809d626e35b8733cf7a4cc806ccbed4e (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho objetivou investigar o efeito da adição de de óleo de milho em dietas com diferentes níveis de proteína bruta, para o pintado, Pseudoplatystoma corruscans, no processo de maturação dos gametas quando mantidos em tanques-rede. Para isso foram avaliados: sobrevivência, relação peso vs comprimento, fator de condição e índice gonadossomático. Além dos índices plasmáticos (colesterol, triglicerídeos, lipídios e proteínas totais e ácidos graxos livres) e o perfil de ácidos graxos nos tecidos dessas matrizes. O experimento foi realizado no Pólo Regional, APTA, Pariquera- Açu, SP, de mar/04 a fev/06. Os tratamentos foram: T1: 28% PB; T2: 28% PB + 5% óleo e T3: 40% PB. As dietas não afetaram a qualidade da água nem o crescimento nos 1º e 2º anos de vida. As taxas de sobrevivência foram superiores a 77%. As rações ofertadas não alteraram o processo de maturação gonadal da espécie. Os peixes apresentaram valores elevados de colesterol, triglicerídeos e lipídios totais, quando acondicionados, justificado pelo fato dos animais estarem se adaptando às novas condições. Essa adaptação também levou a um consumo inicial da fração neutra dos SFA nos tecidos, exceto o adiposo. O óleo à dieta provocou aumento nos teores de PUFA n-6 (incluindo o AA) no músculo das fêmeas, importante reserva energética na atividade migratória. Os HUFA e o LA foram incorporados, preferenciamente aos TGs ovarianos, evidenciando função energética aos ovócitos em formação. Fêmeas estão elongando e desaturando os ácidos graxos para formar AA (a partir do LA), DHA e EPA (a partir do LnA). O estudo indicou que a ração de 28% PB, precisa de mais n-3, preferencialmente EPA e DHA em sua composição, uma fez que foram baixos seus teores nos músculo e fígado o que poderiam ter sido mobilizados aos ovócitos em formação ao final da maturação. / The present work aimed to investigate the effect of the addition of C18:2n6, through the corn oil inclusion in diets with different meaning of crude protein, of the surubim, Pseudoplatystoma corruscans, on the process of gamet maturation, for fish maintained in cages. The experiment was conducted in Regional Polo, Pariquera-Açu, SP, mar./04 to feb./06, whith 12 cages distributed in six tanks, with 20 fishes per cage. It was elaborated three treatments, being two repetitions/tank: T1: 28% CP; T2: 28% CP + 5% corn oil and T3: 40% CP. The diets seems not to have affected the water’s quality neither the growth in the 1st and 2nd years old, with a growth superior lightly of the fish of T3. The survival rates were superior to 77%. It can be inferred that the offered diet did not cause hystomorfologic alterations during the process of gonadal maturation of this species. However, the index gonadossomático (IGS) and the condition factor (K) were slightly advanced and superior in the animals fed with the diet enriched with corn oil.

Made available in DSpace on 2015-07-13T12:10:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-08-11. Added 1 bitstream(s) on 2015-07-13T12:24:09Z : No. of bitstreams: 1 000836344.pdf: 1551165 bytes, checksum: 49d3df701c66be32f547fcbaebe0981c (MD5) / O objetivo deste estudo foi avaliar os efeitos da suplementação do meio de cultivo com ácido linoleico e/ou catalase, em meio sem a adição de SFB, cultivados em atmosfera de baixa tensão de oxigênio sobre o desenvolvimento, qualidade e criotolerância de embriões bovinos. Em um grupo foi feita a suplementação com 100 μM de ácido linoleico (LA); 100UI de catalase (CAT) em um segundo, no terceiro grupo foram feitas as 2 suplementações (CAT+LA) e um quarto grupo sem suplementação (CONTROLE), durante todo o período de cultivo em atmosfera de 5%CO2, 7%O2 e 88%N2 em BAGS. As taxas de clivagem não diferiram (P>0,05) entre os grupos. Porém as taxas de produção de embriões em D7 e D8 diferiram (P<0,05), sendo que o controle obteve melhor resultado perante os 3 tratamentos e o grupo CAT+LA gerou a menor taxa de produção (30,7; 22,4; 19,8; 12,4%). Observou-se um atraso no desenvolvimento, sendo os blastocistos expandidos somente encontrados no D8. Na avaliação do conteúdo total de lipídios, houve uma redução significativa (P<0,05) nos 3 grupos tratados em relação ao controle. A medida dos níveis intracelulares de ROS não foi afetada nos 4 grupos (P>0,05). A quantidade de células totais foi significativamente menor (P<0,05) no grupo CAT+LA, e o grupo CAT foi o que apresentou maior porcentagem de células apoptóticas. Em relação à taxa de re-expansão às 24 horas (P<0,05), o grupo controle (50%) e o CAT (67,2%) apresentaram menores taxas que os grupos LA (71,7%) e o CAT+LA (76,7%). Às 48 horas, o grupo controle apresentou a menor taxa (35,7%), seguido pelo grupo CAT (47,5%). Já o grupo LA (56,5%) diferiu estatisticamente do controle mas não dos grupos CAT (47,5%) e CAT+LA (76,7%). O grupo CAT+LA diferiu estatisticamente dos grupos controle e CAT. Com base nestes resultados, embriões tratados com LA ou CAT+LA no cultivo in vitro, na ausêncio... (Resumo completo, clicar acesso eletrônico abaixo) / The most commonly recommended way to obtain more resistant in vitro embryos during the cryopreservation process is to change these embryos, whether through removal of fetal bovine serum (FBS), addition of different supplements to the culture medium or changes in oxygen tension in the production process. The objective of this study was to assess the effects of supplementation of the culture medium with linoleic acid and/or catalase in medium without the addition of FBS, in low tension oxygen atmosphere on development, quality and cryotolerance of bovine embryos. In one group, the medium was supplemented with 100 μm of linoleic acid (LA); the second was supplemented with 100UI of catalase (CAT), a third group was supplemented with both, CAT+LA and a fourth group received no supplementation (control), during the entire culture period in an atmosphere of 5% CO2, 7% O2 and N2 88% in BAGS. Cleavage rates did not differ (P>0.05) between groups (72.7; 74.1; 72.1; and 72.0%, respectively). However, embryo production rates in D7 and D8 were different (P<0.05), where the control had the highest blastocyst rate of the treatments and the CAT+LA group presented the lowest rate of production (30.7; 22.4; 19.8; 12.4%). Expanded blastocysts were only foundon D8, indicating a delay in development. There was a significant reduction (P<0.05) of total lipids in the 3 treated groups when compared to the control group. There was no difference in the intracellular levels of ROS between the 4 groups (P>0.05).Total cell number was significantly lower (P<0.05) in the CAT+ LA and the CAT group showed the highest percentage of apoptotic cells. Considering the re-expansion rates in 24 hours (P<0.05), the control group (50%) and the CAT group (67.2%) presented lower rates than the LA group (71.7%) and CAT+LA group (76.7%). At 48 hours, the control group showed the worst rate (35.7%) followed by the CAT group (47.5%)...(Complete abstract eletronic access below)

Made available in DSpace on 2014-06-11T19:28:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-25Bitstream added on 2014-06-13T19:16:09Z : No. of bitstreams: 1 pivaro_tm_me_jabo.pdf: 588445 bytes, checksum: 95df0e35e0500ea8feeb836651cb1172 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / No presente trabalho, avaliou-se o efeito do processo de maturação na qualidade da carne do músculo Longissimus de 35 tourinhos da raça Nelore confinados por 96 dias e abatidos com peso de 532,17 ± 30,25kg e 24 meses de idade. Os animais foram alimentados com uma dieta controle sem a adição de óleo e outras quatro dietas contendo diferentes fontes de óleo (soja ou linhaça) protegido ou não da degradação ruminal. Após o abate e 24 horas de resfriamento foram retirados 3 bifes de 2,5cm de espessura entre a 12a e 13a costelas do músculo Longissimus, posteriormente embalados à vácuo e maturados em estufa B.O.D. à temperatura de 2oC durante 7, 14 e 21 dias. Em seguida, foram analisadas as seguintes características: força de cisalhamento, ph, cor, perdas na maturação e composição química da carne assada. Após liofilização, o extrato etéreo foi extraído, metilado e as leituras realizadas por cromatografia gasosa. O delineamento estatístico utilizado foi em blocos casualizados, sendo 5 tratamentos, em 7 blocos e utilizadas 4 medidas repetidas no tempo. As variáveis foram avaliadas por meio de análise de variância e teste t Student à 5% de probabilidade e para as características sensoriais da carne foi utilizado o teste não paramétrico de Kruskal-Wallis. Houve efeito significativo para as variáveis matéria seca, extrato etéreo e matéria mineral. A força de cisalhamento apresentou diferenças entre os grupos de bifes maturados, (5,97; 4,31; 3,25 e 2,96kgf/cm2, para 0, 7, 14 e 21 dias de maturação, respectivamente), sendo que o tempo 14 e 21 foram mais macios que o tempo 7, e este, mais macio que o tempo 0. O ph apresentou diferença entre a carne in natura e os períodos de maturação. Houve efeito significativo para a maturação das variáveis luminosidade, intensidade da cor vermelha e intensidade da cor amarela. As perdas por exsudação na maturação... / In this study, we assess the effect of the ageing process in the meat quality of Longissimus muscles from 35 Nellore bulls young bulls confined for 96 days and slaughtered weighing 532.17 ± 30.25 kg and 24 months of age. The animals were fed with five different diets: the first one was a control diet, without oil and the other four diets containing different oil sources (soy or flaxseed) protected or not from ruminal degradation. After slaughter and 24 hours of cooling, 3 samples with 2.5 cm thickness were removed between the 12th and 13th ribs of Longissimus muscles and subsequently vacuum packaged and aged in an environmental chamber at a temperature of 2o C for 7, 14 and 21 days. We assess the characteristics: shear force, pH, color, ageing losses, chemical composition and fatty acids of meat. The fatty acids were assess by gas chromatography. Variables were evaluated by analysis of variance and Student t test at 5% probability and the sensory characteristics of meat was used nonparametric Kruskal-Wallis test. Shear force differed between the ageing groups, (5.97; 4.31, 3.25 and 2.96 Kgf/cm2 to 0, 7, 14 and 21 days) the period 14 and 21 were softer than the period 7. The pH was different between the fresh beef and the other periods. There was a significant effect on the variable lightness, red color intensity and intensity of yellow color. The losses were larger as the period of ageing increased, and the period of 21 days showed 5.58% of losses. The sensory evaluation showed the difference to variable smoothness for the period of 7 days.. There was a significant effect on concentration of myristic acids (C14: 0), miristoleico \ (C14: 1), pentadecanoic (C15: 0), palmitic (C16: 0), palmitoleic (C16: 1) vacênico (C18: 1 n7) and oleic (C18: 1 n9). In contrast there was an increase in the levels of stearic (C18: 0), linoleic (C18: 2 n6) eicosenoic (C20: 1 n9), eicosadienoico (C20: 2) ... (Complete abstract click electronic access below)

Resumo: O presente trabalho objetivou investigar o efeito da adição de de óleo de milho em dietas com diferentes níveis de proteína bruta, para o pintado, Pseudoplatystoma corruscans, no processo de maturação dos gametas quando mantidos em tanques-rede. Para isso foram avaliados: sobrevivência, relação peso vs comprimento, fator de condição e índice gonadossomático. Além dos índices plasmáticos (colesterol, triglicerídeos, lipídios e proteínas totais e ácidos graxos livres) e o perfil de ácidos graxos nos tecidos dessas matrizes. O experimento foi realizado no Pólo Regional, APTA, Pariquera- Açu, SP, de mar/04 a fev/06. Os tratamentos foram: T1: 28% PB; T2: 28% PB + 5% óleo e T3: 40% PB. As dietas não afetaram a qualidade da água nem o crescimento nos 1º e 2º anos de vida. As taxas de sobrevivência foram superiores a 77%. As rações ofertadas não alteraram o processo de maturação gonadal da espécie. Os peixes apresentaram valores elevados de colesterol, triglicerídeos e lipídios totais, quando acondicionados, justificado pelo fato dos animais estarem se adaptando às novas condições. Essa adaptação também levou a um consumo inicial da fração neutra dos SFA nos tecidos, exceto o adiposo. O óleo à dieta provocou aumento nos teores de PUFA n-6 (incluindo o AA) no músculo das fêmeas, importante reserva energética na atividade migratória. Os HUFA e o LA foram incorporados, preferenciamente aos TGs ovarianos, evidenciando função energética aos ovócitos em formação. Fêmeas estão elongando e desaturando os ácidos graxos para formar AA (a partir do LA), DHA e EPA (a partir do LnA). O estudo indicou que a ração de 28% PB, precisa de mais n-3, preferencialmente EPA e DHA em sua composição, uma fez que foram baixos seus teores nos músculo e fígado o que poderiam ter sido mobilizados aos ovócitos em formação ao final da maturação. / Abstract: The present work aimed to investigate the effect of the addition of C18:2n6, through the corn oil inclusion in diets with different meaning of crude protein, of the surubim, Pseudoplatystoma corruscans, on the process of gamet maturation, for fish maintained in cages. The experiment was conducted in Regional Polo, Pariquera-Açu, SP, mar./04 to feb./06, whith 12 cages distributed in six tanks, with 20 fishes per cage. It was elaborated three treatments, being two repetitions/tank: T1: 28% CP; T2: 28% CP + 5% corn oil and T3: 40% CP. The diets seems not to have affected the water's quality neither the growth in the 1st and 2nd years old, with a growth superior lightly of the fish of T3. The survival rates were superior to 77%. It can be inferred that the offered diet did not cause hystomorfologic alterations during the process of gonadal maturation of this species. However, the index gonadossomático (IGS) and the condition factor (K) were slightly advanced and superior in the animals fed with the diet enriched with corn oil. / Orientador: Elizabeth Romagosa / Coorientador: Maria Beatriz P.P. Oliveira / Banca: Gilberto Moraes / Banca: Gustavo Orlando Bonilla Rodríguez / Banca: Wilson Rogério Boscolo / Banca: Neuza Jorge / Doutor