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Réponses physiologiques et biochimiques à une limitation nutritive en phosphore ou en azote sur la réorientation métabolique des lipides polaires chez différentes espèces de microalgues marines / Physiological and biochemical responses to a phosphorus or nitrogen limitation on the metabolic reorientation of polar lipids in different marine microalgal speciesHuang, Bing 28 November 2018 (has links)
Les bétaïne lipides (BL) sont des lipides polaires qui se distinguent des phospholipides (PL)par l’absence de phosphore (P). La réorientation métabolique induite par une limitation en P chez des microalgues produisant des BL (Tisochrysis lutea et Diacronema lutheri, Haptophytes) ou en produisant peu (Phaeodactylum tricornutum, Bacillariophyte) a été comparée à celle induite par une limitation en azote (N). Le devenir et le flux de carbone dans différentes voies de biosynthèse ont été étudiés par une approche pluridisciplinaire.La limitation nutritive en P ou en N affecte différemment le métabolisme du carbone selon les espèces microalgales. La limitation en P réduit fortement l’activité photosynthétique et la respiration chez P. tricornutum et T. lutea. Par conséquent, l’accumulation de carbone est plus élevée que sous limitation en N chez ces deux espèces. Les deux limitations stimulent en particulier la synthèse des lipides neutres et / ou des glucides. Le remplacement des PL par les BL a été observé chez P. tricornutum en condition de limitation en P. Ce résultat est en accord avec une augmentation de la transcription du gène codant la bétaïne lipide synthase. En revanche, cette limitation ne modifie pas les teneurs en BL rapportées au carbone chez T. lutea et D. lutheri. La composition en acides gras des différentes classes lipidiques est modifiée selon l’espèce microalgale et l’élément nutritif limitant. Une attention particulière a été portée aux acides gras de la série oméga-3, notamment l’acide eicosapentaénoïque (EPA, 20:5 ω3) et l’acide docosahexaénoïque (DHA, 22:6 ω3) dont les proportions varient en fonction de l’élément limitant,de l’espèce et de la classe lipidique. L’augmentation de la production des lipides neutres et / ou des lipides polaires, notamment des bétaïne lipides, riches en DHA et/ou EPA induite par un stress nutritif laisse envisager une valorisation de ces molécules d’intérêt dans différents domaines dont la nutrition et la santé. / Betaine lipids (BL) are P-free polar lipids, conversely to phospholipids (PL). The metabolic reorientation induced by phosphorus (P) limitation in microalgae producing BL (Tisochrysis lutea and Diacronema lutheri, Haptophyta) or producing low levels of BL (Phaeodactylum tricornutum, Bacillariophyta) was compared to that induced by nitrogen (N) limitation. The carbon destiny and flow in different biosynthetic pathways were studied with a multidisciplinary approach. P or N limitation differently affected carbon metabolism according to microalgal species. P limitation highly decreased photosynthetic activity and respiration of P. tricornutum and T. lutea. Consequently, carbon accumulation was higher than under N limitation in these two species. Both limitations stimulated the synthesis of neutral lipids and / or carbohydrates. Replacement of PL by BL was observed in P. tricornutum under P limitation. This result is in agreement with a transcription increase of the gene encoding BL synthase. On the other hand, this limitation did not modify BL contents in reference with carbon in T. lutea or D. lutheri. Fatty acid composition of the different lipid classes was modified according to the microalgal species and the limiting nutrient. Particular attention was paid to the fatty acids of the omega-3 series, notably eicosapentaenoic acid (EPA, 20:5 ω3) and docosahexaenoic acid (DHA, 22:6 ω3), the proportions of which vary according to the limiting element, species and lipid class. The increase in the production of neutral lipids and / or polar lipids, especially betaine lipids, rich in DHA and / or EPA induced by nutritive stress suggests a valorization of these molecules of interest in various areas including nutrition and health.
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Addition of chia (Salvia hispanica L.) flour to chicken nuggets with reduced sodium content / Adição de farinha de chia (Salvia hispanica L.) em nuggets de frango com teor de sódio reduzidoBarros, Julliane Carvalho 14 February 2019 (has links)
The present study aimed to reformulate chicken nuggets to become a healthier meat product, using two different strategies: addition of chia (Salvia hispanica L.) flour in replacement of the chicken skin, aiming to improve the fatty acids profile and also fibres enrichment, and reduction of sodium content by replacing sodium chloride with calcium chloride. The chia flour presents high fibres (33.61 g/100 g) and α-linolenic fatty acid (omega-3; 64.97 g/100 g fat) contents. Evaluating the replacement of 0-20% chicken skin by chia flour, it was possible to observe that the addition of chia flour did not compromise the technological characteristics of the meat product. Moreover, the treatments with 5-20% chia flour showed high omega-3 content. The nuggets containing 10% chia flour can be considered a \"source of fibre\" and the ones containing 15% or more of chia flour, as having \"high fibre content\". On the other hand, the dark coloration of the chia flour affected the colour of the chicken nuggets, causing a sensory rejection for the attribute internal appearance. However, although chia flour has influenced the sensory parameters evaluated, it was verified that the addition of up to 10% of the chia flour was considered acceptable by the consumers. The substitution of 0-75% of sodium chloride by calcium chloride with an ionic strength equivalent to 1.5% NaCl in the chicken nuggets showed that the physicochemical characteristics and sensory acceptance were not affected. A reduction of up to 75% NaCl was only able to reduce 34% sodium in chicken nuggets, which can be labelled as \"reduced sodium content\". The consumption of one portion (130 g) of chicken nuggets with the maximum addition of CaCl2 could provide 16.9% of the recommended daily intake of calcium for adults in Brazil. And finally, the chicken nuggets, reformulate through the substitution of 10% chicken skin with chia flour and 75% sodium chloride per calcium chloride was evaluated. These nuggets showed increased protein content, reduced sodium content and an improvement of the lipid profile, due to the increase of α-linolenic acid. The microbiological analysis showed that the addition of chia flour and CaCl2 did not affect the microbial growth. Regarding the sensory test, addition of chia flour to the different treatments of chicken nuggets caused lower acceptability. However, about 50% of consumers considered samples of chicken nuggets containing chia flour as acceptable. Therefore, it is concluded that the addition of chia flour and CaCl2 together may be considered an even better strategy to obtain healthier chicken nuggets than their addition alone. / O objetivo do presente estudo foi reformular nuggets de frango, para torná-lo mais saudável, usando duas diferentes estratégias: adição da farinha de chia (Salvia hispanica L.) em substituição da pele de frango, objetivando melhorar o perfil lipídico e também enriquecer com fibras, e a redução do teor de sódio pela substituição do cloreto de sódio por cloreto de cálcio. A farinha de chia apresentou altos teores de fibras (33,61 g/100 g) e ácido graxo α-linolênico (ômega-3; 64,97 g/100 g lipídeos). Avaliando a substituição de 0-20% da pele de frango por farinha de chia, foi possível observar que esta adição não comprometeu as características tecnológicas do produto cárneo. Além do mais, os tratamentos com 5-20% de farinha de chia apresentaram um aumento no teor de ômega-3. Os nuggets contendo 10% de farinha de chia podem ser considerados como \"fonte de fibras\" e com 15% ou mais, como \"alto teor de fibras\". Por outro lado, a coloração escura da chia afetou a cor dos nuggets de frango, causando rejeição sensorial para o atributo aparência interna. Entretanto, apesar da farinha de chia ter influenciado os parâmetros sensoriais avaliados, verificou-se que a adição de até 10% foi considerada aceitável pelos provadores. Já a substituição de 0-75% do cloreto de sódio por cloreto de cálcio, com uma força iônica equivalente a 1,5% de NaCl nos nuggets de frango, mostrou que as características físico-químicas e sensoriais não foram afetadas. A redução de até 75% do NaCl reduziu 34% do sódio nos nuggets de frango, o qual pode ser rotulado como \"teor de sódio reduzido\". Adicionalmente, o consumo de uma porção (130 g) de nuggets de frango com a máxima adição de CaCl2 pode fornecer 16,9% da ingestão diária de cálcio recomendada para adultos no Brasil. E finalmente, avaliou-se os nuggets de frango reformulados com a substituição da pele de frango por farinha de chia e NaCl por CaCl2. Os resultados mostraram aumento no teor de proteínas, redução no teor de sódio e melhoria do perfil lipídico, devido ao aumento do ácido α-linolênico. As análises microbiológicas mostraram que a adição da farinha de chia e CaCl2 não afetou o crescimento microbiano. Em relação ao teste sensorial, a adição de farinha de chia nos diferentes tratamentos de nuggets de frango causou baixa aceitabilidade. No entanto, em torno de 50% dos provadores consideraram as amostras de nuggets de frango contendo farinha de chia aceitáveis. Portanto, conclui-se que a adição da farinha de chia e do CaCl2 em conjunto pode ser considerada uma estratégia adequada para tornar este produto cárneo ainda mais saudável do que quando adicionados isoladamente.
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Omega-3 fatty acids, micronutrients and cognitive and behaviour problems associated with child attention deficit hyperactivity disorderSinn, Natalie January 2006 (has links)
This thesis concerns the role of nutrients in cognitive and behaviour problems associated with child attention deficit hyperactivity disorder (ADHD). Study 1 investigated relationships between Conners' ADHD Index ratings, fatty acid deficiency symptoms (FADS), and cognitive performance in a normal population of children. Studies 2 and 3 comprised a 30 week intervention trial investigating effects of n-3 PUFA supplementation on ADHD symptoms in 7-12 year old children with high ADHD scores.
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Genetic and nutritional studies to elucidate the role of adipose tissue in the pathogenesis of metabolic syndromeKalupahana, Nishan Sudheera 01 August 2011 (has links)
Obesity is a major health problem in the United States and worldwide. It increases the risk for type-2 diabetes and cardiovascular diseases. A chronic low-grade inflammation occurring in white adipose tissue (WAT) is causally linked to the development of insulin resistance (IR), metabolic syndrome and obesity-associated chronic diseases. The aim of this dissertation research was to elucidate the WAT function in metabolic syndrome using genetic (overexpression of an adipose pro-inflammatory hormone, angiotensinogen) and nutritional manipulations/approaches (caloric restriction and omega-3 fatty acids), with specific emphasis on the role of inflammation.
Previous research indicates that WAT renin-angiotensin system (RAS) is overactivated in obesity. However, its role in the pathogenesis of IR is hitherto unknown. Using mice overexpressing angiotensinogen (Agt), the only precursor for the hypertensive hormone angiotensin (Ang) II, in WAT, we showed that adipose-specific RAS overactivation leads to systemic IR. This is at least in part due to Ang II, NADPH oxidase and NF-kB-dependent increases in WAT inflammation.
Caloric restriction is the main dietary intervention to treat obesity-associated metabolic disorders. While most health agencies recommend a low-fat diet, energy-restricted high-fat diets (HFR) are also claimed to be effective in this regard. Here, we show that weight loss due to HFR is accompanied by improvements of IR but only partial resolution of WAT inflammation. Further, this diet negatively impacted the adipokine profile supporting the current recommendations for low-fat diets.
Dietary interventions targeted at reducing WAT inflammation have not been explored in detail. Eicosapentaenoic acid (EPA) is an omega-3 polyunsaturated fatty acid of marine origin with anti-inflammatory properties. We show that EPA is able to both prevent and reverse high-fat diet-induced IR and hepatic steatosis via modulation of WAT inflammation.
In conclusion, primary changes occurring in WAT, such as overexpression of Agt, can lead to WAT inflammation and systemic IR. Moreover, nutritional interventions targeting at reducing adiposity (caloric restriction) and inflammation (EPA) can both lead to improvements in systemic IR. Our findings support the current recommendation of low-fat diets for improvement in metabolic profile and show that dietary modulation of WAT function can be used to improve metabolic derangements in obesity.
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Effects of dietary fat and fiber on the oxidative status of the small intestine and colon of ratsSanders, Lisa Merle 16 August 2006 (has links)
Colon cancer is one of the most commonly diagnosed cancers in the US, yet small intestine cancer is a rare event. While there are many similarities between these two tissues, inherent differences such as redox status, may contribute to the variation in cancer occurrence. We examined the difference in reactive oxygen species (ROS) generation, antioxidant enzyme activity and oxidative DNA damage in the small and large intestine of rats under normal conditions and following exposure to exogenous oxidative stress. Basal ROS and antioxidant enzyme activities were greater in the colon than the small intestine, and the balance of ROS to antioxidant enzymes in the colon was more pro-oxidant than in the small intestine. During oxidative stress, ROS and oxidative DNA damage were greater in the colon than the small intestine. Thus the colon responds to oxidative stress less effectively than the small intestine, possibly contributing to increased cancer incidence at this site. We next wanted to understand how diets containing a combination of fish or corn oil and pectin or cellulose may alter the redox environment of the colon. ROS, oxidative DNA damage, antioxidant enzyme activity and apoptosis were measured in colonocytes of rats fed one of four diets containing either corn oil or fish oil and cellulose or pectin. Measurements were madein rats untreated with carcinogen and rats exposed to a chemical carcinogen and radiation. In rats not treated with a carcinogen, fish oil enhanced ROS, and fish oil/pectin suppressed antioxidant enzymes as compared to corn oil/cellulose. Oxidative DNA damage was inversely related to ROS in the fish oil/pectin diet and apoptosis was enhanced relative to other diets. In carcinogen treated and irradiated rats, a similar protective effect was seen with fish oil/pectin as evidenced by a reduction in oxidative DNA damage and enhancement of apoptosis. This suggests that a diet containing fish oil/pectin may protect against colon carcinogenesis by modulation of the redox environment to promote apoptosis and minimize oxidative DNA damage.
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Biomarkers of fish consumption and risk of stroke or myocardial infarctionWennberg, Maria January 2010 (has links)
The effect of fish consumption on the risk of cardiovascular disease has been extensively studied. Omega-3 fatty acids present in fish, namely eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been found to have beneficial effects through several mechanisms. In addition, selenium, an antioxidant, may be protective. Fish also represents the main human exposure source to the pollutant methylmercury (MeHg), which is associated with elevated cardiovascular risk in previous studies. The aim of this thesis was to evaluate whether MeHg is associated with the risk of myocardial infarction (MI) or stroke, whether EPA+DHA or selenium (Se) have protective associations, and if the overall association between fish consumption and risk of stroke or MI is detrimental or protective. A prospective incident case-control study design was used to study effects on stroke or MI. Three hundred and sixty-nine cases with twice as many matched controls were included in the study on stroke, while 431 cases with 499 controls participated in the MI study, all from the Northern Sweden Health and Disease Study. The data was collected from health examinations of the population from 1986 until 1999. Also, time trends in burdens of mercury (Hg), lead (Pb) and cadmium (Cd) in erythrocytes (Ery) from 1990 to 1999 were examined. The food frequency questionnaire (FFQ) used in the case-control studies was correlated with measurements of fatty acids in erythrocyte membranes as biomarkers of intake. In this northern Swedish population, levels of Ery-Hg and Ery-Pb decreased during the 1990´s, but Ery-Cd decreased only in smoking men. No significant associations were found between Ery-Hg or levels of EPA+DHA and the risk of stroke. Men reporting fish consumption >3 meals/week had an elevated risk of stroke. In the MI study, higher levels of Ery-Hg were associated with lower risk of MI. No clear associations were found for reported fish consumption, levels of EPA+DHA or Ery-Se. The validated FFQ has a fair reliability in estimating intake of fatty acids EPA and DHA. However, the low variation in fish consumption in the general population in combination with different versions of the FFQ (with pre-defined, multiple choice alternatives) decreased the reliability of self-reported fish consumption in the case-control studies on risk of stroke or MI. In conclusion, MeHg has no harmful association regarding the risk of stroke or MI in this population with generally low exposure levels. The protective association regarding risk of MI is probably due to Ery-Hg being a biomarker for consumption of fish, a source of other beneficial nutrients. Thus, in this population the benefits of the nutrients in fish appear to overcome the potential harm of MeHg. The finding of elevated stroke risk related to high fish consumption in men will be investigated further. / PHIME; Public health impact of long-term, low-level mixed element exposure in susceptible population strata
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Maternal diet and essential fatty acid metabolism in progeny chickensBullock, Cheri Jean 07 February 2013 (has links)
During the 21 day incubation period, the fertile egg provides nutrients such as fatty acids for energy and polyunsaturated fatty acids (PUFA) for membrane synthesis to the developing chick. The hypothesis tested in the present study is that the type of PUFA fed to the breeder hen can alter tissue lipid composition and PUFA metabolism in the progeny during growth. The objective of the present study was to test two different sources of PUFA (n-3 or n-6) on: 1) egg production, egg, and chick quality; and 2) changes in tissue PUFA composition and metabolism in progeny during growth. Fertilized eggs (n=240) were collected from Ross breeder hens (n=45) fed one of the three experimental diets containing 3.5% fish (long chain n-3), flax (18:3 n-3), or safflower oil (18:2 n-6). The egg and yolk weight was lowest for eggs from hens fed fish oil (P=0.09, P=0.02). The chick weight on day of hatch was 41.2, 45.3, and 43.3g, for fish, flax, and safflower, respectively (P=0.003). In the second experiment fertilized eggs were collected from Lohman Brown layer hens (n=75) fed a control, high n-3, or low n-3 diet. Chicks were raised up to day 14 on a control diet lacking long-chain n-6 and n-3 fatty acids. Chick tissue samples (gastrointestinal tract, liver, and blood) were collected
on day 1, 7, and 14 and were subjected to fatty acid (FA) and interleukin-6 (IL-6) analysis. The long-chain n-6 to long chain n-3 ratio was lowest in the duodenum, jejunum, ileum, and liver from chicks hatched from fish oil fed hens (P<0.001) up to day 14. Interleukin-6 was lowest in liver (P=0.009) and serum on day of hatch, for fish oil chicks. The results from this study show that the diet fed to breeder hens alters progeny tissue PUFA composition and lipid metabolism during early development in avians. The long term effects of maternal diet manipulation on progeny growth and lipid metabolism need to be investigated in detail. / Graduation date: 2013
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Effects of dietary fat and fiber on the oxidative status of the small intestine and colon of ratsSanders, Lisa Merle 16 August 2006 (has links)
Colon cancer is one of the most commonly diagnosed cancers in the US, yet small intestine cancer is a rare event. While there are many similarities between these two tissues, inherent differences such as redox status, may contribute to the variation in cancer occurrence. We examined the difference in reactive oxygen species (ROS) generation, antioxidant enzyme activity and oxidative DNA damage in the small and large intestine of rats under normal conditions and following exposure to exogenous oxidative stress. Basal ROS and antioxidant enzyme activities were greater in the colon than the small intestine, and the balance of ROS to antioxidant enzymes in the colon was more pro-oxidant than in the small intestine. During oxidative stress, ROS and oxidative DNA damage were greater in the colon than the small intestine. Thus the colon responds to oxidative stress less effectively than the small intestine, possibly contributing to increased cancer incidence at this site. We next wanted to understand how diets containing a combination of fish or corn oil and pectin or cellulose may alter the redox environment of the colon. ROS, oxidative DNA damage, antioxidant enzyme activity and apoptosis were measured in colonocytes of rats fed one of four diets containing either corn oil or fish oil and cellulose or pectin. Measurements were madein rats untreated with carcinogen and rats exposed to a chemical carcinogen and radiation. In rats not treated with a carcinogen, fish oil enhanced ROS, and fish oil/pectin suppressed antioxidant enzymes as compared to corn oil/cellulose. Oxidative DNA damage was inversely related to ROS in the fish oil/pectin diet and apoptosis was enhanced relative to other diets. In carcinogen treated and irradiated rats, a similar protective effect was seen with fish oil/pectin as evidenced by a reduction in oxidative DNA damage and enhancement of apoptosis. This suggests that a diet containing fish oil/pectin may protect against colon carcinogenesis by modulation of the redox environment to promote apoptosis and minimize oxidative DNA damage.
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Atténuation de la dépression post-infarctus par une diète riche en oméga-3 ou par la prise de probiotiquesGilbert, Kim 06 1900 (has links)
L'Infarctus du myocarde (IM) provoque, chez le rat, une augmentation de l'apoptose dans le
système limbique en plus d'induire des symptômes qui s'apparentent à la dépression chez
l'humain. Nous avons démontré qu'une diète élevée en oméga-3 ou la prise de probiotiques
pouvaient être efficaces pour réduire ces effets si ces interventions débutaient avant
l'induction de l'ischémie myocardique. Cette étude a pour objectif de déterminer l'efficacité
de ces interventions si elles débutent après l'ischémie myocardique.
L’IM a été induit chez le rat mâle Sprague-Dawley par l’occlusion de l’artère coronaire
descendante antérieure gauche pendant 40 minutes. À la suite de l’ischémie, les rats ont
reçu des probiotiques (1 billion de bactéries vivantes de L. helveticus R0052 et de B.
longum R0175) ou un véhicule dans leur eau de boisson en présence d'une diète élevée ou
faible en oméga-3. À 3 jours post-IM, l’activité enzymatique de la caspase-3 et le nombre
de cellules dUTP nick-end labelling (TUNEL) positives sont diminués dans les régions
CA1 et le corps godronné de l’hippocampe ainsi que dans l’amygdale en présence de la
diète élevée en oméga-3. La prise de probiotiques atténue également l’activité de la
caspase-3 et le nombre de cellules TUNEL positives dans le corps godronné et l’amygdale
médiane. À 2 semaines post-IM, le comportement dépressif évalué par 3 tests
comportementaux (test d’interaction sociale, test de nage forcée et test d’évitement passif) a
été observé chez le groupe recevant la diète faible en oméga-3 sans probiotiques et le
comportement dépressif a été atténué avec la diète élevée en oméga-3 et/ou la prise de
probiotiques. Les probiotiques ont augmenté les niveaux plasmatiques d’interleukine-4 (IL-
4) tandis que la diète élevée en oméga-3 a montré une diminution de la protéine
chimiotactique monocytaire 1 (MCP-1).
Ces résultats indiquent qu’une diète élevée en oméga-3 ou la prise de probiotiques,
débutant à la suite de l’IM, s’avèrent bénéfiques pour atténuer la dépression et l’apoptose
dans le système limbique. / Proinflammatory cytokines play a central role in depressive-like behavior and apoptosis in
the limbic system after myocardial infarction (MI). Polyunsaturated fatty acids (PUFA)
omega-3 diet or the combination of Lactobacillus helveticus R0052 and Bifidobacterium
longum R0175 probiotics, when given before ischemic period, reduce circulating
proinflammatory cytokines as well as apoptosis in the limbic system. This study was
designed to determine if the same nutritional interventions maintain their beneficial effects
when started after the onset of the reperfusion period and attenuate depressive-like
behavior.
MI was induced by the occlusion of the left anterior descending coronary artery for 40
minutes in rats. After the onset of reperfusion, animals were fed with a high or low PUFA
omega-3 diet, combined or not with 1 billion live bacteria of L. helveticus R0052 and B.
longum R0175. At 3 days post-MI, caspase-3 enzymatic activities and terminal dUTP nickend
labelling (TUNEL)-positive cells were decreased in the CA1, dentate gyrus and
amygdala with the high PUFA omega-3 diet as compared to the other diet. Probiotics
attenuated caspase-3 activity and TUNEL-positive cells in the dentate gyrus and the medial
amygdala. At 2 weeks post-MI, depressive-like behaviour, evaluated by 3 behavioural tests
(social interaction, passive avoidance and forced swim test), was observed in the low PUFA
omega-3 diet without probiotics and this behavior was attenuated with the high PUFA
omega-3 diet or/and probiotics. Probiotics increased interleukin-4 plasmatic concentrations
while high PUFA omega-3 diet decreased monocyte chemotactic protein 1 (MCP-1). These
results indicate that a high PUFA omega-3 diet or the administration of probiotics, starting
iii
after the onset of reperfusion, are beneficial to attenuate post-MI depression and apoptosis
in the limbic system.
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Prostate Cancer Diagnosis : experimental and Clinical Studies With HRMAS NMR SpectroscopyStenman, Katarina January 2011 (has links)
A few abnormal cells found in a small piece of prostate tissue are most consequential for a man’s future. The prevalence of prostate cancer (PCa) is increasing globally. The main instigating factor for this cancer is not yet known, but it appears to be the consequence of many variables such as an increasingly older population, more frequent PSA-testing, and factors involving lifestyle. Prostate cancer screening, as an equivalent for breast cancer screening, has been suggested but unfortunately there are no accurate diagnostic tools available for this type of screening. The reason for this is simply that the prostate is one of the most difficult organs to diagnose and, consequently, PCa screening would generate far too many false-positive and false-negative results. The prostate is not easily accessible as it is deeply-seated in the male pelvic area, wrapped around the urethra and surrounded by sensitive vital organs. Furthermore, PCa is frequently multi-focal, and the cancer cells have a tendency of assimilating among normal cells and, thus, do not always form solid lumps. Therefore, prostate tumors are often not felt by digital rectal examination (DRE) or identified by imaging. The PSA-test is not reliable as it is more prostate-specific than cancer-specific. Due to increasing prostate awareness, more early-stage and locally confined PCa are being detected. This is saving lives, although there is a high risk of over treatment and unnecessary side-effects. The increased detection of PCa requires sophisticated diagnostic methods and highly skilled clinicians who can discern between indolent and aggressive cancers. The current “gold-standard” for PCa diagnosis is biopsy grading by pathologists using the Gleason score system, which is a difficult task. Therefore, innovative methods to improve the precision of prostate diagnosis, by increased biopsy sensitivity and tumor localization, are of essence. In light of these difficulties, the metabolomic approach using 1D and 2D high-resolution magic angle spinning (HRMAS) NMR spectroscopy combined with histopathology on intact prostatectomy specimens was evaluated in this research project. The non-destructive nature of HRMAS NMR enables spectroscopic analysis of intact tissue samples with consecutive histological examinations under light microscope. Metabolomics aids in the unraveling and the discovery of organ-specific endogenous metabolites that have the potential to be reliable indicators of organ function and viability, extrinsic and intrinsic perturbations, as well as valuable markers for treatment response. The results may, therefore, be applied clinically to characterize an organ by utilizing biomarkers that have the capacity to distinguish between disease and health. The aim was to characterize the human and the rat prostate in terms of its intermediary metabolism, which I show here to differ between species and anatomical regions. Furthermore, the aim is to seek the verification of HRMAS NMR derived metabolites which are known to be a part of the prostate metabolome such as, citrate, choline, and the polyamines which were performed, but also the identification of metabolites not previously identified as part of the local prostate metabolism, such as Omega-6, which was detected in tumors. The extended aim was to elucidate novel bio-markers with clinical potential. In this study, the common phyto-nutrient, inositol, which appears to possess protective properties, was identified as being a potentially important PCa bio-marker for the distinction between the more indolent Gleason score 6 and the more aggressive Gleason score 7 in non-malignant prostate tissues with tumors elsewhere in the organ. Further studies in this area of PCa research are therefore warranted.
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