RESUMO
BACKGROUND: Recent studies have suggested that men with elevated plasma levels of insulin-like growth factor-I (IGF-I) may have an increased risk of prostate cancer. Furthermore, IGF-binding proteins (IGFBPs) and insulin can modulate the activity of IGF-I. In this study, we sought to determine the role of IGF-I as well as IGFBPs-1, -2, and -3 and insulin as possible etiologic factors for prostate cancer. METHODS: We conducted a nested case-control study within the Northern Sweden Health and Disease Cohort Study. We measured levels of IGF-I, IGFBP-1, IGFBP-2, IGFBP-3, and insulin in plasma samples from 149 men who had a diagnosis of prostate cancer between 1 month and 10 years after blood collection and among 298 control men. All statistical tests are two-sided. RESULTS: Case subjects had statistically significantly higher mean levels of IGF-I than control subjects (229 ng/mL; 95% confidence interval [CI] = 218-240 ng/mL] versus 214 ng/mL [95% CI = 208-221 ng/mL]; P =.02) and IGFBP-3 (2611 ng/mL [95% CI = 2518-2704 ng/mL] versus 2498 ng/mL [95% CI = 2437-2560 ng/mL]; P =.04). Conditional logistic regression analyses showed increases in prostate cancer risk with rising levels of IGF-I (P:(for trend) =.02) and IGFBP-3 (P(for trend) =.03). In case subjects younger than 59 years at the time of blood collection, the risk associated with increased IGF-I was higher (P:(for trend) =.01), whereas the risk associated with increased IGFBP-3 was lower (P(for trend) =.44) than the corresponding risks in the full cohort. Prostate cancer risk was not associated with levels of IGFBP-1, IGFBP-2, or insulin. CONCLUSIONS: Prostate cancer risk is increased in men with elevated plasma IGF-I. This association was particularly strong in younger men in this study, suggesting that circulating IGF-I may be specifically involved in the early pathogenesis of prostate cancer.
Assuntos
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias da Próstata/sangue , Fatores Etários , Idoso , Estudos de Casos e Controles , Estudos Transversais , Humanos , Insulina/sangue , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/imunologia , Risco , Fatores de Risco , Fatores de TempoRESUMO
BACKGROUND: Obesity surgery is expanding, the quality of care is ever more important, and learning curve assessment should be established. A large registry cohort can show long-term effects on obesity and its comorbidities, complications, and long-term side effects of surgery, as well as changes in health-related quality of life (QoL). Sweden is ideally suited to the task of data collection and audit, with universal use of personal identification numbers, nation-wide registries permitting cross-matching to analyze causes of death, in-hospital care, and health-related absenteeism. METHOD: In 2004, the Scandinavian Obesity Surgery Registry (SOReg) was initiated and government financing secured. A project group created a national database covering all public as well as private hospitals. Data entry was to be made online, operative definitions of comorbidity were formed, and complication severity scored. Several forms of audit were devised. RESULTS: After pilot studies, the system has been running in its present form since 2007. Since 15 January 2013, SOReg covers all bariatric surgery centers in Sweden. The number of operations in the database exceeded 40,000 (March 2014), with a median follow-up of 2.94 years. Audit shows that >98% of data are correct. All results are publicized annually on the Internet. COMMENTS: Using this systematic approach, it has been possible to cover >99% of all bariatric surgery, cross-matching our data with nation-wide registries for in-hospital care, cause of death, and permitting regular nation-wide audit. Several scientific studies have used, or are using, what seems to be the most comprehensive database in obesity surgery.
Assuntos
Obesidade Mórbida/epidemiologia , Obesidade Mórbida/cirurgia , Sistema de Registros , Adulto , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/estatística & dados numéricos , Estudos de Coortes , Comorbidade , Feminino , Seguimentos , Humanos , Internet , Masculino , Complicações Pós-Operatórias/epidemiologia , Qualidade de Vida , Sistema de Registros/estatística & dados numéricos , Suécia/epidemiologiaRESUMO
A Western lifestyle has been implicated in the pathogenesis of prostate cancer. However, no clear association between obesity and prostate cancer has been shown. Leptin may stimulate prostate growth and angiogenesis, and receptors for leptin are present in the prostate. Leptin may, thus, be associated with increased risk of prostate cancer. One hundred forty-nine men with prostate cancer were identified (together with 298 matched referents) who, before diagnosis, had participated in population-based health surveys in Northern Sweden. Blood pressure, body mass index, and use of tobacco were recorded. Leptin, insulin, insulin-like growth factor I (IGF-I), IGF-I-binding proteins 1-3, testosterone, and sex hormone-binding globulin were analyzed in stored samples. Their influences on prostate cancer were estimated by conditional logistic regression analysis. Prostate cancer specimens were investigated for immunoreactivity for the leptin receptor. Relative risk (95% confidence intervals) estimates of prostate cancer over the quintiles of leptin were 1.0, 2.1 (1.1-4.1), 2.6 (1.4-4.8), 1.4 (0.7-2.7), and 1.6 (0.8-3.2). Adjustments for metabolic variables, testosterone, and IGF-I and its binding proteins did not attenuate this increased risk. Immunoreactivity for the leptin receptor was detected in normal, high-grade prostatic intraepithelial neoplasia lesions and malignant prostatic epithelium. Moderately elevated plasma leptin concentrations are associated with later development of prostate cancer. This may be due to direct effects of leptin on prostatic intraepithelial neoplasia lesions, or to indirect actions through other mechanisms. A critical fat mass related to an interior milieu favorable for prostate cancer development seems to exist, because intermediate but not high leptin levels are related to prostate cancer risk.
Assuntos
Leptina/análise , Neoplasias da Próstata/sangue , Receptores de Superfície Celular , Adulto , Idoso , Pressão Sanguínea , Índice de Massa Corporal , Proteínas de Transporte/análise , Epitélio/química , Feminino , Inquéritos Epidemiológicos , Humanos , Insulina/sangue , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Neoplasia Prostática Intraepitelial/sangue , Neoplasia Prostática Intraepitelial/química , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Receptores para Leptina , Fatores de Risco , Globulina de Ligação a Hormônio Sexual/análise , Fumar , Suécia , Testosterona/sangueRESUMO
BACKGROUND AND PURPOSE: Recent experimental evidence suggests that overexpression of bcl-2, a protein functioning by blocking apoptosis, may influence the treatment outcome in human tumours, including prostate cancer. To test the clinical implications of this hypothesis, tumours from patients with prostate cancer treated with external beam radiotherapy were investigated for bcl-2 immunoreactivity (IR) and correlated with prognosis and treatment outcome. MATERIALS AND METHODS: Bcl-2 IR was evaluated in archival tumour specimens obtained through transurethral resection from 42 patients with localized prostate cancer (T0-T4, N0 and M0). Bcl-2 IR expression was related to stage, grade and cancer-specific survival. Specimens were obtained prior to administrating routine radiotherapy for all patients. RESULTS: Bcl-2 IR was present in 19/42 (45%) tumours. The bcl-2-positive patients had a significantly longer cancer-specific survival than the bcl-2-negative patients (10.3 versus 3.4 years, P<0.04). At follow-up (7-19 years), nine patients were still alive, 26 patients had died of prostate cancer and seven patients had died of other causes. CONCLUSIONS: This study indicates that pre-treatment bcl-2 overexpression is related to a favourable outcome in prostate cancer treated with radiotherapy. Low bcl-2 along with a high stage may be a predictor of poor prognosis and these patients might benefit from additional treatment.
Assuntos
Neoplasias da Próstata/radioterapia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Idoso , Biomarcadores Tumorais/metabolismo , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/mortalidade , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
The short-term effects of rye bran bread intake in prostate cancer were investigated. Ten men with conservatively treated prostate cancer were randomised to a daily supplement of 295 g of rye bran bread and eight men to 275 g of wheat bread (control) with similar fibre content for three weeks. Blood samples, ultrasound-guided core biopsies of the prostate, and urine samples were taken. In the rye group, there was a significant increase in plasma enterolactone, and the apoptotic index increased significantly from 2.1% (SD 1.3) to 5.9% (SD 1.8), P<0.005 as measured by a TUNEL index in four cases in the rye group and seven cases in the control group. Besides a significant decrease in weight in both groups, only small changes were observed in plasma concentrations of prostate specific antigen (PSA), circulating sex hormones, excreted oestrogens, insulin-like growth factor (IGF)-I, and in the endothelial fibrinolytical system. High intake of rye bran bread is suggested to increase apoptosis in prostate tumours.
Assuntos
Apoptose , Pão , Neoplasias da Próstata/fisiopatologia , Secale , Idoso , Divisão Celular , Fibras na Dieta , Estrogênios/farmacocinética , Hormônios Esteroides Gonadais/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/análise , Neoplasias da Próstata/irrigação sanguínea , Neoplasias da Próstata/terapia , Somatomedinas/análise , Redução de PesoRESUMO
The objective of this study was to investigate the effect of outdoor rearing on the fatty acid (FA) composition and contents of tocopherols of M. longissimus dorsi polar (PL) and neutral lipids (NL) in entire males, castrated males and female pigs. Fat content did not differ between genders or rearing conditions. In PL of the indoor pig muscle the level of n-6 highly unsaturated fatty acids (HUFA) was higher in females and entire males compared with castrated males. The outdoor environment resulted in a slightly higher level of n-3 polyunsaturated FA (PUFA) in muscle PL and NL of entire males compared with females and castrated males. We also found an increased level of 18:2 n-6 in the muscle PL of outdoor reared females compared with the indoor females. The higher levels of PUFA in the entire male muscle, in both PL and NL, were not accompanied by a higher level of vitamin E.
RESUMO
The objective of this study was to investigate the polar and neutral lipid fatty acid composition of pig muscle as influenced by rearing conditions and sex. A total of 120 Hampshire crossbreeds were divided in two groups, one reared free-range in a strip grazing fashion and one reared indoors in a large pen (120 m(2)). Free-range rearing produced a more unsaturated fatty acid composition (M. biceps femoris) in the neutral lipids, although the effect was small. In the polar lipids the effect of rearing condition was sex dependent. In the muscle of free-range gilts, there was a higher level of C18:2 n-6, compared with indoor gilts, indoor castrates, and free-range castrates. Moreover, muscle of gilts irrespective of rearing condition, had a higher level of the C⩾20 polyunsaturated fatty acids in the polar lipids (16.75 and 14.60, respectively). Thus, we suggest that the difference between castrates and gilts with respect to fatty acid composition in the polar lipids, might be affected by rearing condition.
RESUMO
In two patients with severe tetanus the skeletal muscle metabolism was studied. Muscle biopsies were taken 4-6 weeks after the development of tetanus. The patients were treated during this time with a neuromuscular blocking agent. In one of the patients a biopsy was also taken before treatment, 2 days after the first symptoms of the disease. Enzyme activities representative for glycogen synthesis, glycogen greakdown, glycolysis, fatty acid beta-oxidation and respiratory chain, and fluxes of glucose, palmitate and leusine in vitro, and the concentrations of glycogen, triglycerides, phospholipids, cholesterol, proteins and RNA were determined in the muscle tissue. The enzyme activities in the muscle tissue examined 2 days after the development of tetanus were close to normal, excep for decreased activities of phosphofructokinase and glycogen synthase. After 4-6 weeks of treatment the fluxes of glucose and palmitate and the corresponding enzyme activities were low in both patients. These findings are consistent with muscular inactivity. In contrast the activity of glucose-6-phosphate dehydrogenase, the incorporation rate of leucine-carbon into proteins and the RNA content were high, indicating a high protein synthesis as a probable manifestation of active repairative processes. It is concluded that the skeletal muscle metabolism in these patients was affected in a degenerative manner and that this effect was attributed more to the treatment than to the disease per se. Dynamic physical training under supervision is recommended for the period after the generalized spasms to overcome the "disuse" effects in the skeletal muscles.
Assuntos
Músculos/metabolismo , Pancurônio/uso terapêutico , Tétano/tratamento farmacológico , Idoso , Feminino , Glucosefosfato Desidrogenase/metabolismo , Glicogênio/biossíntese , Humanos , Metabolismo dos Lipídeos , Pessoa de Meia-Idade , Proteínas Musculares/metabolismo , Músculos/enzimologia , RNA/metabolismo , Tétano/metabolismoRESUMO
The enzyme pattern in gastrocnemius muscle tissue was studied in 39 patients with peripheral arterial insufficiency. Phosphofructokinase and glucose-6-phosphate-dehydrogenase were significantly increased in the skeletal muscles from these patients. The most pronounced changes were found in 3-OH-acyl-CoA-dehydrogenase, citrate synthase, and in cytochrome-c-oxidase. These enzyme activities were increased by 60, 40 and 25 per cent respectively. In patients with claudication as the only symptom, the metabolic capacity was generally increased in skeletal muscles affected by the low blood flow. With increasing severity of arterial insufficiency, all enzyme activities decreased and glycolytic enzymes were affected first. 3-OH-acyl-CoA-dehydrogenase, citrate synthase and cytochrome-c-oxidase activities were still comparatively high in patients with gangrenous foot ulcers, indicating some maintenance of the muscle viability even in situations with very low blood flow.
Assuntos
Arteriopatias Oclusivas/enzimologia , Músculos/enzimologia , Adulto , Idoso , Metabolismo Energético , Feminino , Gangrena/enzimologia , Humanos , Claudicação Intermitente/enzimologia , Perna (Membro)/irrigação sanguínea , Masculino , Pessoa de Meia-IdadeRESUMO
The relationships between the carnitine concentration and enzyme activities representative of different metabolic pathways, glycogenolysis, glycolysis, beta-oxidation of fatty acids, citric acid cycle, and respiratory chain were studied in skeletal muscle tissue from 18 volunteering subjects. In addition, the in vitro incorporation rates of glucose-carbon and palmitate-carbon into different metabolites, and the concentration of glycogen, triglycerides, and phospholipids were determined in the same tissue specimen. The carnitine concentration correlated positively and statistically significantly with the activities of 3-OH-acyl-CoA dehydrogenase and citrate synthase, with the incorporation rate of palmitate-carbon into CO2, and the incorporation rate of glucose-carbon into lactate in the muscle tissue. The results indicate a coupling between the concentration of carnitine and the capacity for long-chained fatty acid oxidation in human skeletal muscles.
Assuntos
Oxirredutases do Álcool/metabolismo , Carnitina/metabolismo , Citrato (si)-Sintase/metabolismo , Hexoquinase/metabolismo , L-Lactato Desidrogenase/metabolismo , Músculos/metabolismo , Oxo-Ácido-Liases/metabolismo , Fosfofrutoquinase-1/metabolismo , Fosforilases/metabolismo , Adulto , Idoso , Glucose/metabolismo , Glicogênio/metabolismo , Glicólise , Humanos , Pessoa de Meia-Idade , Músculos/enzimologia , Palmitatos/metabolismo , Fosfolipídeos/metabolismo , Triglicerídeos/metabolismoRESUMO
The activities (Vmax) of hexokinase, glycogen phosphorylase, glucose-6-phosphate dehydrogenase, phosphofructokinase, lactate dehydrogenase, citrate synthase, cytochrome c oxidase, and 3-OH-acyl-CoA dehydrogenase in human skeletal muscles were compared with the in vitro utilization of glucose and palmitic acid assessed under optimal conditions. Statistically significant correlations between substrate fluxes and enzyme activities were found suggesting that the substrate incorporation rate in vitro in some way reflects the capacity of metabolic pathways. The incorporation rate of leucine into muscle proteins was also statistically significantly correlated to the RNA concentration in the muscle tissue. Glycolytic and glycogenolytic enzymes correlated significantly to each other and correlations were also found between aerobic enzymes supporting the validity of constant proportions between certain key enzymes in human skeletal muscles.
Assuntos
Glucose/metabolismo , Leucina/metabolismo , Músculos/metabolismo , Ácidos Palmíticos/metabolismo , RNA/metabolismo , Oxirredutases do Álcool/metabolismo , Citrato (si)-Sintase/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Hexoquinase/metabolismo , Humanos , Cinética , L-Lactato Desidrogenase/metabolismo , Fosfofrutoquinase-1/metabolismo , Fosforilases/metabolismoRESUMO
The conditions of determination of the in vitro incorporation rate of palmitate-carbon into CO2 in human skeletal muscles were studied. Muscle biopsies were taken from 25 patients with nonmuscular diseases and incubated in a metabolic shaker with KRP as medium and palmitate as substrate. Substrate saturation was achieved beyond a palmitate concentration of 2.5 mmol/1, and the incorporation rate was linear with time for 2 hr. The activity of 3-hydroxy-acyl-CoA-dehydrogenase (ACDH), an enzyme involved in the beta-oxidation, was also determined. Both the incorporation rate of palmitate-carbon into CO2 and the activity of ACDH were higher in the leg muscles than in the abdominal muscles. Significant positive correlations were found between the incorporation rate of palmitate-carbon into CO2 and the ACDH activity, and between the incorporation rate and the phospholipid concentration in muscles. These correlations indicate that this in vitro system is valid for evaluation of the metabolism of fatty acids in skeletal muscle tissue.
Assuntos
Músculos/metabolismo , Palmitatos/metabolismo , Ácidos Palmíticos/metabolismo , Abdome , Acetilcoenzima A/metabolismo , Oxirredutases do Álcool/metabolismo , Carbono/metabolismo , Dióxido de Carbono/metabolismo , Colesterol/metabolismo , Coenzima A , Feminino , Humanos , Hidroxiácidos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Fosfolipídeos/metabolismo , Triglicerídeos/metabolismoRESUMO
Glucose metabolism and skeletal muscle enzyme activities were studied in nineteen cancer patients and twelve matched controls. The fasting insulin values were normal but the fasting glucose values and the sum of glucose were increased and the sum of insulin was decreased during intravenous glucose tolerance test in the cancer patients. The elimination rate of glucose (k-value) during glucose challenge was, however, not significantly different in cancer patients as compared with that of appropriate controls. The activities of enzymes representative for glycogen turnover, glycolysis, citric acid cycle and respiratory chain were significantly lower in the muscle tissue of cancer patients, while the activity of 3-hydroxyacyl-CoA dehydrogenase, an enzyme in the beta-oxidation of fatty acids, was unchanged and the activity of glucose-6-phosphate dehydrogenase was significantly higher. Rate limiting enzyme activities in muscle tissue, phosphofructokinase and cytochrome c oxidase correlated signficantly with plasma insulin and glucose during glucose challenge. The results point at the possibility of covariating debilitation of pancreatic beta-cells and skeletal muscle enzymes caused by the malignant tumour.
Assuntos
Glicemia/metabolismo , Músculos/enzimologia , Neoplasias/metabolismo , Idoso , Ciclo do Ácido Cítrico , Feminino , Teste de Tolerância a Glucose , Glicogênio/metabolismo , Glicólise , Humanos , Insulina/sangue , Ilhotas Pancreáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Mitocôndrias Musculares/enzimologiaRESUMO
An in vitro preparation of human skeltal muscle tissue aimed to be a model for clinical metabolic studies was functionally and structurally characterized. Muscle fibres from biopsy specimens obtained at surgical operations were teased away and collected in incubation vessels for the following determinations: exchangeable water content, extracellular space, potassium content, incorporation rate of labeled leucine into proteins, uptake of labeled cycloleucine, alpha-aminoisobutyric acid (AIB), and 3-o-methy1-glucose into the intracellular space, and the incorporation rate of glucose into various metabolites. After various times of incubation, muscle fibre samples were also taken for light and electron microscopy. During the incubation of the muscle fibres a transient intracellular oedema was demonstrated by electron microscopy and by determination of the exchangeable water content. The restitution of this oedema was associated with an increasing intracellular potassium concentration. Active transport of leucine, cycloleucine and AIB showing competitive inhibition was registered. The incorporation of labeled leucine into proteins was linear during 4 h of incubation and optimal stimulation of this incorporation was demonstrated in the presence of a complete amino acids mixture at a concentration corresponding to 10 times the normal plasma concentration in man. Insulin stimulated the incorporation rate of glucose-carbon into all metabolites and ouabain stimulated its incorporation in to glycogen. Monoidoacetate inhibited the incorporation of glucose into all metabolites.
Assuntos
Aminoácidos/metabolismo , Músculos/metabolismo , Transporte Biológico Ativo , Cicloleucina/metabolismo , Espaço Extracelular/metabolismo , Feminino , Glucose/metabolismo , Glicogênio/metabolismo , Humanos , Lactatos/metabolismo , Leucina/metabolismo , Masculino , Pessoa de Meia-Idade , Mitocôndrias Musculares/metabolismo , Proteínas Musculares/metabolismo , Músculos/ultraestrutura , Miofibrilas/metabolismo , Potássio/metabolismo , Fatores de Tempo , Equilíbrio HidroeletrolíticoRESUMO
Biopsies from vastus lateralis muscle of male patients suffering from chronic ethanol abuse were studied with regard to histochemical reactions of ATPase and NADH-diaphorase; enzymatic activities of triosephosphate dehydrogenase (TPD), lactate dehydrogenase (LD), and cytochrome c oxidase (cytox); content of ATP, creatine phosphate, and glycogen; and volume fractions of fat, mitochondria, and fibrillar and extrafibrillar space. The results were compared with those from controls without known abuse of ethanol. The relative numbers of fibers were the same in two groups, but the size of the fast-twitch-glycolytic (white) fibers was diminished in the alcoholic group. The activities of TPD and LD were diminished in skeletal muscle of the alcoholics. This is most probably caused by the reduced amount of fast-twitch-glycolytic tissue, as there was a good correlation between this amount and the activity of the two enzymes. The activity of cytox was slightly lower in muscle of the alcoholics than in that of the controls. The volume fraction of mitochondria was lower in the alcoholic group than in the control group. Volume fractions of fat and fibrillar and extrafibrillar space were equal in the two groups. No significant differences were found in the amount of glycogen and ATP in the muscle of the two groups. However, the content of creatine phosphate is higher in the alcoholic group than in the control group.
Assuntos
Alcoolismo/enzimologia , Etanol/farmacologia , Músculos/enzimologia , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Adulto , Depressão Química , Di-Hidrolipoamida Desidrogenase/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Glicogênio/metabolismo , Glicólise/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/metabolismo , Masculino , Pessoa de Meia-Idade , Mitocôndrias Musculares/ultraestrutura , Músculos/efeitos dos fármacos , Músculos/ultraestrutura , Miofibrilas/ultraestrutura , Consumo de Oxigênio/efeitos dos fármacos , Fosfocreatina/metabolismoRESUMO
Whilst analyzing the morphological effects of a 3-week dietary intervention in patients with prostate cancer, we made an unexpected observation to the effect that prostate biopsy trauma may, at least transiently, increase prostate tumor cell proliferation. Further studies are needed to evaluate the clinical significance of this observation.
Assuntos
Biópsia por Agulha/efeitos adversos , Suplementos Nutricionais , Estrogênios não Esteroides/administração & dosagem , Isoflavonas , Invasividade Neoplásica/patologia , Antígeno Prostático Específico/análise , Neoplasias da Próstata/dietoterapia , Neoplasias da Próstata/patologia , Divisão Celular , Método Duplo-Cego , Seguimentos , Humanos , Masculino , Fitoestrógenos , Projetos Piloto , Preparações de Plantas , Medição de Risco , Resultado do TratamentoRESUMO
Fibers from the m. vastus lateralis of 10 middle-aged men were classified at ultrastructural level according to the appearance of the sarcomeric M-band. The Z-band widths had a two-peak distribution. One peak was due to type 1 fibers (mean 125 +/- 11 nm), the other to type 2 fibers. This latter could be separated into type 2A (101 +/- 9 nm) and type 2B (86 +/- 8 nm). About 83% of the fibers would have been correctly classified on the basis of the Z-band width alone. Mitochondrial volumes differed (type 1 5.6 +/- 0.8, 2A 4.0 +/- 0.8, and 2B 2.8 +/- 0.8%). However, only one third (37%) of the fibers would have been correctly classified if sorted according to this parameter. Mitochondrial volumes in the different fibers were correlated to mitochondrial enzymes, while fiber sizes and numbers were correlated to cytoplasmic variables. The correlations appeared mainly after a training program, suggesting that the relationships between structural and functional parameters are more obvious after adaptation to higher functional demands.
Assuntos
Mitocôndrias Musculares/enzimologia , Músculos/ultraestrutura , Esforço Físico , Adulto , Citrato (si)-Sintase/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glucosefosfato Desidrogenase/metabolismo , Histocitoquímica , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Mitocôndrias Musculares/ultraestrutura , Músculos/enzimologiaRESUMO
Metabolic alterations in skeletal muscles and liver tissue from cancer patients were compared with corresponding alterations in mice (C-57) with sarcoma (MCG-101). In tumor-bearing man and mice similar changes in enzyme activities and in protein turnover were found. Glycolytic and oxidative enzyme activities were decreased in skeletal muscle tissue. Tumor-associated increase in lysosomal enzyme activities was found in both species. Leucine was incorporated into skeletal muscle proteins at a lower rate and into hepatic proteins at a higher rate in both species with malignant tumor. In tumor-bearing mice ribosome profiles from skeletal muscle, heart muscle and liver showed a preponderance of slowly sedimenting units of polyribosomes suggesting that initiation of protein synthesis may be a rate limiting step. The metabolic host reactions in tumor-bearing mice were similar to those in cancer patients implying that experimental tumors are relevant to use for analysis of mechanisms behind the development of cancer cachexia in man.
Assuntos
Fígado/metabolismo , Músculos/metabolismo , Neoplasias/metabolismo , Sarcoma Experimental/metabolismo , Adulto , Idoso , Animais , Caquexia/etiologia , Modelos Animais de Doenças , Feminino , Glicólise , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Miocárdio/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/complicações , Distúrbios Nutricionais/metabolismo , RNA Neoplásico/metabolismoRESUMO
The metabolic and morphologic adaptation to physical training in skeletal muscle tissue of eleven middle-aged, physically untrained men was studied. Muscle biopsies were taken from the vastus lateralis before, after 8 weeks and after 6 months of physical training for analysis of metabolic and morphologic variables. Glucose tolerance test indicated increased insulin sensitivity after 6 months of physical training. The activities of glycogen phosphorylase, hexokinase and glucose-6-P-dehydrogenase were increased but other enzymes involved in glycogen turnover and glycolysis were unchanged after 6 months of physical traning. The activities of citrate synthase and cytochrome-c-oxidase, representing the oxidative capacity were significantly increased already after 8 weeks of physical training. The incorporation rate of palmitate-carbon into CO2 and triglycerides increased, and the incorporation rate of leucine-carbon into CO2 decreased with 6 months of physical training. The fiber diameter of both Type 1- and Type 2-fibers increased, while the mitochondrial volume increased predominantly in Type 2-fibers. Significant correlations were found between metabolic, physiologic and morphologic variables before and after physical training. The results indicate an increased oxidative capacity, mainly located to Type 2-fibers, and an increased utilization of fatty acids in response to this type of physical training.
Assuntos
Músculos/metabolismo , Educação Física e Treinamento , Carnitina/metabolismo , Citrato (si)-Sintase/metabolismo , Ácidos Graxos/metabolismo , Teste de Tolerância a Glucose , Glicogênio/metabolismo , Glicólise , Humanos , Metabolismo dos Lipídeos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Mitocôndrias Musculares/ultraestrutura , Proteínas Musculares/metabolismo , Músculos/ultraestrutura , Oxirredução , Aptidão FísicaRESUMO
BACKGROUND: In this study, we investigated whether dietary intervention could inhibit tumor growth of an androgen-sensitive human prostatic cancer. METHODS: LNCaP cells were transplanted subcutaneously in nude-mice. The animals were then put on different diets and tumor take, tumor growth and prostate specific antigen (PSA) secretion were studied during 9 weeks. RESULTS: Palpable tumors developed in 75% of the tumor-cell injected sites in animals fed a control diet (corn starch, sucrose, etc.) whereas, for animals given rye bran (RB), ethyl acetate extraction from rye bran supplemented cellulose based diets (CCEE), palpable tumors were seen in only 30% and for soy protein based diets (SCC) 50% of the transplantation sites, respectively. The tumors that grew to palpable size in the rye (RB) and soy (SCC) groups were smaller and secreted less PSA than those in the control group. In the rye and soy groups tumor cell apoptosis was increased, but cell proliferation was unaffected. Addition of fat to the rye diet reduced its effect on prostate cancer growth. CONCLUSIONS: Factors in rye bran and soy protein may inhibit prostate cancer growth. The effect is more apparent for rye than for soy. Further studies are needed to identify the effective substances and to explore the mechanism of action.