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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Mitochondrial uptake of anthocyanidins and protection from oxidative stress

2012 August 1900 (has links)
The anthocyanins show efficient antioxidant properties and free radical scavenging properties which result in various health-promoting benefits. This research investigated the ability of anthocyanidins to distribute into mitochondria and protect mitochondria from oxidative stress. In an in vitro study, the uptake of pure cyanidin and quercetin, and their 3-glucosylated forms into isolated rat liver mitochondria was tested, along with their effects on mitochondrial oxidative stress parameters. The absorption of cyanidin was significantly higher (67% uptake of 125 µM) than the other three flavonoids. Measurements indicated that the cyanidin was taken up into or tightly bound by mitochondria. Also, results suggested that cyanidin uptake was partially dependent on membrane potential. When incubated together (internally and externally) with mitochondria all tested flavonoids decreased reactive oxygen species (ROS) generation during mitochondrial respiration, and inhibited lipid peroxidation to different extents. Importantly, pre-loaded CY showed much stronger effects against oxidative stress in two analyses than other flavonoids. Due to its greater uptake by mitochondria, cyanidin may provide greater protection in vivo. In an in vivo study, cyanidin, quercetin and their 3-glucosides were administered into rat tail vein to give a dose of 7.6 µmol/Kg body weight. Cyanidin and its glucoside had greater affinity to liver and kidney than did quercetin and its glucoside; particularly, all test tissues contained a significantly higher amount of cyanidin than other test flavonoids. Also, cyanidin accumulated more in liver mitochondria than other flavonoids, and consistent with in vitro results was present in mitochondria to a much greater extent than cyanidin glucoside. However, delivery of the flavonoids at this dose did not significantly affect the liver mitochondria susceptibility to lipid peroxidation or the level of endogenous tissue oxidative damage. Altogether the results show that cyanidin can rapidly and efficiently accumulate in mitochondria, wherein it exhibits strong bio-antioxidant activity against oxidative stress and may help protect mitochondrial function and integrity. Also, the anthocyanidin and its 3-glucoside have greater ability than flavonols to accumulate in organs; especially cyanidin presented in liver mitochondria to a much greater extent. Cyanidin could be a potent natural antioxidant compound that is effective in mitochondria-protective therapies.
2

Antioxidant properties of NQO2

Jumuddin, Farra Aidah January 2018 (has links)
Dihydronicotinamide riboside (NRH) quinone oxidoreductase 2 (NQO2) is involved in quinone metabolism reducing quinone to hydroquinone. Quinones are products of oestrogen metabolism and are responsible for the oestrogen-initiated breast carcinogenesis. It has been demonstrated that oestrogen quinones are endogenous biological substrates of NQO2 which acting as a detoxification enzyme catalyses the reduction of oestrogen quinones to hydroquinone. Hydroquinone can then be removed by conjugation to glutathione or glucuronic acid. In this study, the oestrogen dependent and oestrogen independent effects of NQO2 in a variety of networks implicated in breast tumorigenesis were investigated aiming to understand the potential role of NQO2 overexpression in mammary carcinomas. The use of NRH as a cofactor for NQO2 is being studied in parallel with the Î2-oestradiol and tamoxifen treatments. The MCF-7, T47D, MDA-MB-231 and MDA-MB-468 breast cancer cells were transfected with increasing amounts of NQO2 and its biological activity in regulating ERα transcriptional activity, reactive oxygen species (ROS) generation, cell cycle control, mitochondrial membrane potential and antioxidant activities including catalase activity, glutathione (GSH) levels and glutathione peroxidase (GPx) activity were studied. NQO2 overexpression in MDA-MB-231 and T47D cells reduced ROS generation. Increasing amounts of transfected NQO2 induced the ERα transcriptional activity in Î2-oestradiol treated MCF-7 and T47D cells and decreased cyclin D1 protein levels in these cells treated with Î2-oestradiol compared to untransfected cells. Reduction of catalase activity was detected in tamoxifen treated T47D cells overexpressing NQO2, an effect that was not evident in Î2-oestradiol treated cells, whereas NQO2 mediated reduction of GSH levels was detected in these cells treated with Î2-oestradiol but not with tamoxifen. Finally, NQO2 affected mitochondrial membrane depolarization in Î2-oestradiol treated MDA-MB-231 cells. Given the fact that NRH is not physiologically synthesized in humans, the results presented in this study are valuable from the fundamental science point of view indicating the existence of a potential link between NQO2 and estrogens affecting a number of biological pathways important for breast carcinogenesis and as such from the clinical angle it could be assumed that NQO2 effects could impact the design of personalised breast cancer treatment of oestrogen receptor positive and negative breast cancers.
3

Effect Of Drought And Salt Stresses On Antioxidant Defense System And Physiology Of Lentil (lens Culinaris M.) Seedlings

Ercan, Oya 01 February 2008 (has links) (PDF)
In this study, 14 days old lentil seedlings (Lens culinaris Medik cv. Sultan), which were subjected to 7 days of drought (20% PEG 6000), and salt (150 mM NaCl ) stress , were examined in a comparative manner for the effects of drought and salt stress treatments. In shoot and root tissues physiological parameters such as wet-dry weight, relative water content, root-shoot lengths, membrane electrolyte leakage, and lipid peroxidation in terms of malondialdehyde (MDA) were determined. H2O2 content, proline accumulation and chlorophyll fluorescence analysis were also performed. Changes in the activity of antioxidant enzymes such as superoxide dismutase (SOD: EC 1.15.1.1), catalase (CAT: EC 1.11.1.6) ascorbate peroxidase (APX: EC 1.11.1.11) and glutathione reductase (GR: EC 1.6.4.2) were observed upon stress treatments. In salt treated lentil seedlings, significant decreases in wet-dry weight, RWC, shoot-root length and chlorophyll fluorescence measurements indicated a sensitivity, when compared to drought treated plants. Higher MDA concentration and higher electrolyte leakage amounts are supported these results. APX, GR and proline seem to play important roles in antioxidant defense against salt stress for both tissues by removing reactive oxygen species and protecting macromolecules and membranes. GR and proline are also maintains the main protective mechanism against drought stress effects. SOD is active in drought stressed roots and salt stressed shoots, where the H2O2 contents are also observed to be increased.
4

Vliv chronicky podávaných subletálních dávek parakvatu na délku telomer a rezistenci vůči oxidačnímu stresu drozofily

TOMÁŠKOVÁ, Jindřiška January 2016 (has links)
As the most widely dispersed fauna around the world, insects are exposed to a range of stresses within their environments. Oxidative stress causes a disturbance of the balance between production of free radicals and antioxidant response, which leads to various physiological changes in an organism. Despite this, there are several of defense mechanisms, which include in particular the main antioxidant enzymes AKH. In this thesis, I tried to contribute especially to understand the physiological nature of telomere elongation after exposure to free radicals.
5

Physiological And Biochemical Screening Of Different Turkish Lentil Cultivars Under Salt Stress Conditions

Kose, Fatma Selin 01 September 2012 (has links) (PDF)
Salinity is the 2nd major limiting abiotic factor on plant growth. As a result of this, soil salinity greatly reduce the yield of the crop production by dual action on plants which are ionic toxicity and water deficit. Therefore, improvement of stress tolerance is greatly concerned. This study was performed to screen and select a salt-resistant and a salt-sensitive cultivar among 6 Turkish lentil cultivars (Lens culinaris M.) which are &Ccedil / agil, &Ccedil / ift&ccedil / i, Kafkas, Malazgirt, Seyran and &Ouml / zbek according to the physiological and biochemical properties. 12 days old lentil seedlings which were exposed to salt stress (100 mM NaCl and 150 mM NaCl) for 5 days as well as control groups analyzed physiologically by root-shoot fresh weights, and lengths / and biochemically by ion leakage, MDA, H
6

Effect Of Drought And Salt Stresses On The Gene Expression Levels Of Antioxidant Enzymes In Lentil (lens Culinaris M.) Seedlings

Aksoy, Emre 01 September 2008 (has links) (PDF)
This study was carried out for understanding of antioxidant mechanisms of lentil under abiotic stress conditions. For this aim, 14 days old lentil seedlings (Lens culinaris Medik cv. Sultan-1) were subjected to drought (20% PEG 6000), and salt (150 mM NaCl ) stress for 6, 12 and 24 hours, for 3, 5 and 7 days. PCR conditions for Mn SOD, Cu/Zn SOD, chloroplastic/mitochondrial GR, CAT and chloroplast /stromal APX antioxidant enzymes were optimized. Then, total RNA was isolated from stressed and non-stressed plant roots and shoots. The gene expression levels of Mn SOD and Cu/Zn SOD were examined by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) technique. Arabidopsis 18S rRNA was used as internal control in multiplex PCR technique. Relative expression levels of Mn SOD were lower in shoots and roots under salt stress while no significant change was obtained under drought conditions in both tissues. Relative expression levels of Mn SOD were increased on 5th day of salt and drought applications in both shoots and roots. Relative expression levels of Cu/Zn SOD increased after 5th, and on 1st and 7th days of drough treatment in shoots and roots, respectively. On the other hand, expression levels of Cu/Zn SOD increased on 3rd and 5th days of salt treatment in shoot tissues. Although it is nearly impossible to understand the whole antioxidant mechanism of plants under environmental stresses, this study was the first step to learn about molecular background of antioxidant defence mechanisms in lentil.
7

Desenvolvimento in vitro de embriões bovinos cultivados em meio com análago de resveratrol

PATROCÍNIO, Taís T. A. 20 February 2017 (has links)
Submitted by Samira Ramos (samira.ramos@unifenas.br) on 2018-04-25T21:05:10Z No. of bitstreams: 1 TAIS APARECIDA PATROCINIO.pdf: 726977 bytes, checksum: 8cef7ddcd6970bf3d2ccd912eb038060 (MD5) / Made available in DSpace on 2018-04-25T21:05:10Z (GMT). No. of bitstreams: 1 TAIS APARECIDA PATROCINIO.pdf: 726977 bytes, checksum: 8cef7ddcd6970bf3d2ccd912eb038060 (MD5) Previous issue date: 2017-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Fundação de Amparo à Pesquisa do Estado de Minas Gerais - FAPEMIG / This study evaluated the effect of AR33 (patent-pending formula), a resveratrol analogue, in the culture of in vitro fertilized embryos. Cumulus-oocyte complexes (COCs) recovered from bovine ovaries collected at the slaughterhouse were matured in vitro for 24 h and fertilized in vitro for 20 h, both at 38.8 °C under 5% CO2 in air and high humidity. Probably partially nude zygotes were randomly distributed in two experiments. Experiment 1: 0 (control, n = 347), 0.1 μM (n = 337), 0.5 μM (n = 277) and 2.5 μM AR33 (n = 343) with 2.5% fetal bovine serum (FBS) and experiment 2: 2.5 μM AR33 (n = 381), 0.5 μM resveratrol (n = 381), both with 2.5% SFB and 0 (control, n = 341) with 10% FBS. The base medium for all treatments was SOFaa and incubation conditions were 38.8 °C under 5% CO2 in air and high humidity. Half of the culture medium was fed on days 3 and 5 after fertilization. The cleavage rate was evaluated on day 3 and the blastocyst rate (B1) on days 7 and 8 post-fertilization. At day 8, the blastocysts were fixed and subsequently submitted to analysis of the number of cells and apoptotic index. Cleavage and blastocyst rates were analyzed by logistic regression models (Proc Logistic), and the number of cells and apoptotic index by mixed linear models (Proc Mixed) using the SAS statistical package. In experiment 1, the cleavage rate (P <0.05) was higher at 2.5 μM (69.0 ± 4.4%) than at 0, 0.1 and 0.5 μM AR33 (62.1 ± 2.0%, 60.7 ± 5.9% and 56.7 ± 5.8%, respectively). At day 7, the Bl rate was similar (P> 0.05) between 0.1, 0.5 and 2.5 μM (18.1 ± 5.4%, 17.5 ± 2.9% and 19.4 ± 3.3%, respectively) and all were higher (P <0.05) 05) at 0 μM AR33 (12.4 ± 2.5%). At day 8, only 0.1 and 2.5 μM (21.0 ± 5.0% and 24.6 ± 3.3%) were higher than 0 μM AR33 (15.2 ± 2.5%). There was no difference (P> 0.05) between treatments regarding total cell number (TC) and internal cell mass (MCI); However, the apoptotic index in CT and MCI was higher for 0 and 2.5 μM (11.36 and 9.89%, 20.52 and 15.85%) than in 0.1 and 0.5 μM AR33 (4.66 and 4.82%, 8.47 and 10.92%). In the experiment 2 the cleavage rate (P <0.05) was higher in the control (80.8 ± 3.4%) than in the treatment with 0.5 μM resveratrol (76.4 ± 3.6%), but similar to 2.5 μM AR33 (76.9 ± 1.2%). There were no differences (P> 0.05) for the Bl rate on days 7 and 8. The apoptotic index in the CT and MCI was higher in the control (8.9 and 14.9%, respectively) than in the 2.5 μM AR33 and 0.5 μM resveratrol (6.4 and 5.5%, 11.1 and 8.8%, respectively). In conclusion, resveratrol and its synthetic analogue tested in this study improve bovine embryonic development in culture medium supplemented with 2.5% FBS under 5% CO2 in air. / Este estudo avaliou o efeito de AR33 (fórmula com patente-pendente), um análogo de resveratrol, no cultivo de embriões fecundados in vitro. Complexos cumulus-oócitos (COCs) recuperados de ovários bovinos coletados no matadouro, foram maturados in vitro durante 24 h e fertilizados in vitro por 20 h, ambos em 38.8 °C sob 5% de CO2 em ar e alta umidade. Prováveis zigotos parcialmente desnudos foram distribuídos aleatoriamente em dois experimentos. Experimento 1: 0 (controle, n=347), 0.1 µM (n=337), 0.5 µM (n=277) e 2.5 µM de AR33 (n=343) com 2,5% de soro fetal bovino (SFB), e experimento 2: 2.5 µM de AR33 (n=381), 0.5 µM de resveratrol (n=381), ambos com 2,5% SFB e 0 (controle, n=341) com 10% SFB. O meio base para todos os tratamentos foi SOFaa e as condições de incubação foram de 38.8 °C sob 5% de CO2 em ar e alta umidade. Metade do meio de cultura foi renovado (feeding) nos dias 3 e 5 após a fertilização. A taxa de clivagem foi avaliada no dia 3 e a taxa de blastocisto (Bl) nos dias 7 e 8 pós-fecundação. No dia 8, os blastocistos foram fixados e posteriormente submetidos a análise do número de células e índice apoptótico. As taxas de clivagem e de blastocistos foram analisadas por modelos de regressão logística (Proc Logistic), e o número de células e índice apoptótico por modelos lineares mistos (Proc Mixed) usando o pacote estatístico SAS. No experimento 1, a taxa de clivagem (P<0.05) foi maior para 2.5 µM (69.0±4.4%) do que para 0, 0.1 e 0.5 µM de AR33 (62.1±2.0%, 60.7±5.9% e 56.7±5.8%, respectivamente). No dia 7, a taxa de Bl foi semelhante (P>0.05) entre 0.1, 0.5 e 2.5 µM (18.1±5.4%, 17.5±2.9% e 19.4±3.3%, respectivamente) e todos eles foram superiores (P<0,05) à 0 µM AR33 (12.4±2.5%). No dia 8, apenas 0.1 e 2.5 µM (21.0±5.0% e 24.6±3.3%) foram maiores do que 0 µM AR33 (15.2±2.5%). Não houve diferença (P>0,05) entre tratamentos quanto ao número de células totais (CT) e da massa celular interna (MCI); contudo, o índice apoptótico nas CT e na MCI foram maiores para 0 e 2.5 µM (11.36 e 9.89%; 20.52 e 15.85%) do que em 0.1 e 0.5 µM AR33 (4.66 e 4.82%; 8.47 e 10.92%). No experimento 2 a taxa de clivagem (P<0,05) foi maior no controle (80.8±3.4%) do que no tratamento com 0.5 µM resveratrol (76.4±3.6%), e este último semelhante à 2.5 µM AR33 (76.9±1.2%). Não houve diferenças (P>0,05) para a taxa de Bl nos dias 7 e 8. O índice apoptótico nas CT e MCI foi maior no controle (8.9 e 14.9%, respectivamente) do que para 2.5 µM AR33 e 0.5 µM resveratrol (6.4 e 5.5%; 11.1 e 8.8%, respectivamente). Em conclusão, o resveratrol e o seu análogo sintético testado neste estudo melhoram o desenvolvimento embrionário bovino em meio de cultura suplementado com 2,5% SFB sob 5% de CO2 em ar.
8

Valorisation des activités biologiques de certaines espèces végétales sahariennes nord-africaines / Valorisation of the biological activities of some North African Saharan plant species

Palici, Ionut-Florin 30 November 2016 (has links)
La région sahariennne est une des zones les plus défavorables à la croissance et développement des espèces animales. Cependant, peu d’espèces possèdent à la fois des mécanismes morphologiques et écophysiologiques, assurant leur survie dans les sols arides et sur les dunes de sable.En effet, on peut estimer que le métabolisme secondaire biosynthétise des quantités considérables de composés bioactifs, destinés à assurer le développement et la continuité de ces espèces, notamment leur survie dans ces conditions sahariennes précaires.Les propriétés pharmacologiques des extraits de plantes sahariennes peuvent apporter des bénéfices dans la guérison de certaines maladies microbiennes ou prolifératives ou également contribuer au développement de certaines activités antioxydantes.L'étude des propriétés toxiques vise donc à enrichir la connaissance du potentiel bioactif des plantes sahariennes.Ces aspects de la puissance du métabolisme furent étudiés chez certaines espèces végétales strictement sahariennes. Il s’agit de : Anthyllis henoniana Coss., Centropodiaforskalii (Vahl) Cope, Cornulaca monacantha Delile, Ephedra alata var. alenda (Stapf.)Trabut, Euphorbia guyoniana Boiss & Reut., Henophyton deserti Coss. & Durieu,Hélianthemum confertum Dunal, Moltkiopsis ciliata (Forssk.) I.M.Johnst. et Spartidiumsaharae (Coss. & Durieu) Pomel. Les principaux résultats obtenus montrent que ces espèces possèdent des propriétés intéressantes, susceptibles d’être utiles pour le traitement de certaines maladies humaines.En revanche, parfois à certaines concentrations, des extraits de ces espèces peuvent présenter des effets toxiques sur les organismes.En dépit des conditions extrêmes, le Sahara représente la zone de développement d'une certaine diversité biologique, et principalement des espèces de plantes précieuses dont une meilleure connaissance scientifique de leur propriétés phytochimiques se révèle indispensable. / The Saharan desert is one of the most unfavorable areas, to the plant life. However, a small number of plants possesses both morphological and ecophysiological mechanisms ensuring their survival in the arid soil and on the sand dunes.It can be estimated that the secondary metabolism biosynthesizes considerable amounts of bioactive compounds, meant to ensure the development and the continuity of these species.The pharmacological properties of saharan plant extracts may bring benefits in the healing of certain microbial or proliferative diseases or contributes to the supply of antioxidants activities.The study of toxic properties is meant to enrich the knowledge of Saharan plants’bioactive potential.The biological activities of Anthyllis henoniana Coss., Centropodia forskalii (Vahl)Cope, Cornulaca monacantha Delile, Ephedra alata var. alenda (Stapf.) Trabut,Euphorbia guyoniana Boiss & Reut., Henophyton deserti Coss. & Durieu, Helianthemum confertum Dunal, Moltkiopsis ciliata (Forssk.) I.M.Johnst. and Spartidium saharae (Coss.& Durieu) Pomel have been studied. It can be seen that these species possess interesting properties, capitalized in the treatment of some human diseases. But, on the other hand in certain concentrations, extracts from these species may exhibit toxic effects onorganisms.Despite the extreme conditions, the Saharan desert represents the area of development for some valuable plant species, whose scientific knowledge is necessary.
9

Antioxidative und weitere ausgewählte Stoffwechselparameter bei gesunden Kälbern und Jungrindern

Haser, Daniela Irmgard 22 September 2015 (has links)
Einleitung: Es ist wenig darüber bekannt, wie sich das antioxidative System von Kälbern nach der Geburt entwickelt, welche Faktoren darauf Einfluss nehmen und wie sich antioxidative Parameter in ihren Aktivitäten resp. Konzentrationen unter physiologischen Bedingungen verändern. Zielstellung: Ziel dieser Arbeit war es zum einen die altersabhängige Entwicklung antioxidativer Parameter bei gesunden Kälbern und Jungrindern bis zum 18. Lebensmonat zu verfolgen und zum anderen zu evaluieren, ob bei metabolisch gering belasteten Jungrindern jahreszeitliche Differenzen bezüglich Superoxiddismutase (SOD), Glutathionperoxidase (GPX) und Trolox Equivalent Antioxidative Capacity (TEAC) bestehen. Material und Methoden: Es wurden gesunde weibliche Kälber bzw. Jungrinder der Rasse Holstein Friesian / Deutsche Schwarzbunte aus drei Betrieben am 1. (n = 33) und 7. (n = 31) Tag sowie im 1. (n = 33), 3. (n = 33), 6. (n = 5), 9. (n = 5), 12. (n = 32) und 18. (n = 31) Monat post natum (p. n.) klinisch und labordiagnostisch untersucht. Weiterhin wurden in einem Betrieb während eines Jahres im September, November, Januar, März, Mai und Juli jeweils 6 gesunde weibliche Jungrinder, die zum Untersuchungszeitpunkt 12 Monate alt waren, kontrolliert. Die Tiere wurden im Stall in Anbindehaltung gehalten, ausgenommen der im Mai in Weidehaltung untersuchten Tiere. Analysiert wurden im Blut die antioxidativen Parameter SOD, GPX und TEAC, der Hämatokrit (Hkt) und die Stoffwechselparameter Gesamtprotein, Albumin, Bilirubin, Haptoglobin, Harnstoff, Cholesterol, ß-Hydroxybutyrat (BHB), AST, AP, GLDH, CK, Ca, anorganisches Phosphat (Pi) und Fe. Ergebnisse: Ein betrieblicher Einfluss war statistisch nicht nachweisbar. Vom 1. Tag bis zum 18. Monat p. n. zeigten die antioxidativen Parameter SOD, GPX und TEAC einen gleichartigen Verlauf mit einem kontinuierlichen Anstieg bis zum 6. Monat p. n.. Die GPX-Aktivitäten stiegen von 50-80 U/ml Hkt am 1. Tag p. n. auf 100-190 U/ml Hkt im 6. Monat p. n. an. Die niedrigsten Aktivitäten (p<0,05) bestanden am 1. und 7. Tag (62-90 U/ml Hkt) p. n.. Die SOD-Aktivitäten am 1. (4500-5600 U/g Hb) und 7. Tag (4600-5450 U/g Hb) p. n. waren niedriger als im 1. (5400-6800 U/g Hb) und 3. Monat (5600-7800 U/g Hb) p. n. (p<0,05). Der Anstieg der TEAC-Konzentration vom 1. Tag p. n. (220-290 µmol/l) zum 6. Monat p. n. (260-340 µmol/l) war nicht signifikant. Nach dem 6. Monat p. n. fielen die Akti-vitäten resp. Konzentrationen ab, wobei die SOD-Aktivitäten mit 12 (4000-5000 (U/g Hb) und 18 Monaten (3700-5000 U/g Hb) p. n. signifikant niedriger waren als im 1. und 3. Mo-nat p. n.. Die GPX-Aktivitäten lagen mit 12 (118-152 U/ml Hkt) und 18 Monaten (105-150 U/ml Hkt) p. n. signifikant über denen der ersten Lebenswoche. Die TEAC-Konzentrationen waren im 12. Monat p. n. mit 260-320 µmol/l größer als vom 1. Tag bis zum 1. Monat (240-280 µmol/l) p. n. (p<0,05). Die SOD, GPX und TEAC korrelierten außer mit 9 Monaten p. n. zu allen Untersuchungszeitpunkten signifikant positiv. Für AST, AP, CK und Bilirubin wurden am 1. Tag p. n. die signifikant höchsten Aktivitäten resp. Konzen-trationen ermittelt, für Haptoglobin am 7. Tag p. n.. Gesicherte Korrelationen bestanden zwischen Albumin, Bilirubin und der TEAC, zwischen BHB und TEAC, GPX sowie SOD außerdem zwischen Ca und Pi. Im Jahresverlauf waren die GPX-Aktivitäten im September und Januar mit 73-103 U/ml Hkt niedriger als von März bis Juli mit 104-142 U/ml Hkt (p<0,05). Erniedrigte TEAC-Konzentrationen wurden besonders im Januar (272-302 µmol/l) und signifikant im März (265-299 µmol/l) gegenüber September und November (319-345 µmol/l) ermittelt. Die SOD-Aktivitäten differierten nicht gesichert. GPX und SOD korrelierten im ganzen Jahr gesichert, TEAC und SOD außer im Januar ebenfalls, GPX und TEAC nur im November, März, Mai und Juli. Die Stoffwechselparameter befanden sich im physiologischen Bereich, mit Ausnahme von Harnstoff im November und Juli sowie Pi im Mai. Schlussfolgerungen: Es wird geschlussfolgert, dass das antioxidative System der neu-geborenen Kälber zur Geburt noch unreif ist und sich bis zum sechsten Monat p. n. stabilisiert. Die durch den Abbau des fetalen Hämoglobins und die Vormagenentwicklung vermehrt entstehenden ROS tragen zu einer weiteren Aktivitäts- resp. Konzentrationssteigerung der antioxidativen Parameter bis zu einem Maximum im 6. Monat p. n. bei. Danach stellt sich ein Gleichgewicht zwischen Pro- und Antioxidantien ein. Auf die GPX-Aktivitäten und TEAC-Konzentrationen konnte ein jahreszeitlicher Einfluss bei Jungrinden ermittelt werden.

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