Analysis of morbid obese women aerobic potential / Análisis del potencial aeróbico de obesas mórbidas

Abstract Introduction: nowadays, with the increase of world obesity and the numbers of morbidly obese people, a concerning public health problem that is difficult to solve rises up. Objective: to analyse the physiological responses after the 6-minute walk tests and maximum stress test in the arm cycle ergometer in morbidly obese pre-bariatric surgery women. Methods: fifteen level III obesity women aged 35.6 ± 6.6 years took part in this experiment. Firstly, they went through an anamnesis and body composition analysis; secondly, they were submitted to a 6-minute walk test and a maximum stress test in arm cycle ergometer on alternate days. Results: patients were able to perform the maximum stress test and showed better aerobic potentials in the arm cycle ergometer than in the 6-minute walk test. No significant differences were found between SPO2 and diastolic blood pressure between the moments of rest and after the tests, neither in the systolic blood pressure after the 6-minute walk test and the values of rest and post 5 minutes in the maximum stress test. The main differences found were between the maximum systolic blood pressure in the cycle ergometer test and the other moments and the heart rate after the tests and the heart rate at rest. Conclusion: the maximum stress test in arm cycle ergometer is a safe method that allows greater requirement and control applied to the heart system than in the 6-minute walk test. In addition, it allows the development of a more individualized aerobic training and prescription of aerobic physical exercise program.

Resumen Introducción: Actualmente, con el aumento de la obesidad en el mundo y del número de obesos mórbidos se evidencia un problema de salud pública de difícil resolución. Objetivo: analizar las respuestas fisiológicas tras las pruebas de caminata de 6 minutos y de esfuerzo máximo en cicloergómetro de brazos en obesas mórbidas precirugía bariátrica. Métodos: se evaluaron 15 mujeres con obesidad grado III con edad media de 35,6 ± 6,6 años, las cuales participaron inicialmente de una anamnesis con el análisis de la composición corporal y posteriormente participaron en días alternos de la prueba de 6 minutos de caminata y del mismo, prueba de esfuerzo máximo en cicloergómetro de brazos. Resultados: las pacientes lograron realizar la prueba de esfuerzo máximo y demostraron mejores potenciales aeróbicos en el cicloergómetro de brazos que en la prueba de caminata. No se encontraron diferencias significativas entre la SPO2 y la presión arterial diastólica entre los momentos de reposo y después de las pruebas y también en la presión arterial sistólica posterior a la prueba de caminata y los valores de reposo y después de 5 minutos en la prueba de esfuerzo máximo. Las principales diferencias se observaron entre la presión arterial sistólica máxima en la prueba en cicloergómetro y los otros momentos y en la frecuencia cardiaca después de las pruebas y las frecuencias cardiacas en reposo. Conclusión: la prueba de esfuerzo máximo en cicloergómetro de brazos es un método seguro que posibilita mayor exigencia y control aplicado al sistema cardíaco que en la prueba de caminata. Adicionalmente, permite un programa de entrenamiento y una prescripción del ejercicio físico aeróbico más individualizados.

Serum leptin in overt and subclinical hypothyroidism: effect of levothyroxine treatment and relationship to menopausal status and body composition.

BACKGROUND: The relationship between thyroid status, including subclinical hypothyroidism (SH) and serum leptin is controversial or uncertain. Therefore we evaluated serum leptin in SH and overt hypothyroidism (OH) and determined the effects of levothyroxine (LT(4)) replacement on serum leptin in these disorders. METHODS: Serum leptin, thyrotropin (TSH), free thyroxine, insulin, glucose, and body composition parameters were compared in 55 SH, 20 OH, and 28 euthyroid (EU) pre- and postmenopausal women. In addition, the effect of LT(4) treatment on serum leptin in SH and OH was assessed. RESULTS: The mean +/- SD (median) serum leptin concentrations in the OH and SH groups were higher than in the EU group (35.1 +/- 27.2 [33.0] and 36.6 +/- 21.9 [30.6] ng/mL, respectively, vs. 23.2 +/- 19.3 [17.9] ng/mL, p = 0.011), but the difference was only significant in postmenopausal women. The body mass index (BMI), fat mass index (FMI), and the homeostasis model assessment-insulin resistance (HOMA-IR) index values were not different among these groups. In premenopausal women there was no correlation between leptin, BMI, or FMI and serum TSH levels (r(s) = 0.009, p = 0.474; r(s) = 0.043, p = 0.367; r(s) = 0.092, p = 0.232). In the postmenopausal women, the partial correlation coefficient between TSH and leptin was present, even when controlling for BMI (r(s) = 0.297, p = 0.042) and FMI (r(s) = 0.275, p = 0.050). LT(4) treatment was associated with a reduction of serum leptin concentrations in the OH group (p = 0.008). In SH group there were no differences between LT(4) replacement or no treatment, since a fall in serum leptin levels was detected in both SH subgroups, despite a more pronounced fall with LT(4) use. Treatment of the SH and OH groups with LT(4) did not influence HOMA-IR index or body composition. CONCLUSIONS: Serum leptin concentrations are elevated in postmenopausal women with SH or OH. A relationship between thyroid status and serum leptin is further supported by the fact that LT(4) treatment, to restore the EU status, reduced serum leptin levels in OH in the absence of significant effects on BMI. In women, hypothyroidism influences either leptin secretion or degradation and this effect is more pronounced in postmenopausal than in premenopausal women.

Ethanol intake inhibits growth of the epithelium in the intestine of pregnant rats.

The effects of ethanol ingestion on jejunal and ileal epithelial cells were studied in pregnant rats by measuring crypt and villus cell population, crypt cell proliferation, and crypt cell cycle time as parameters. Timed-pregnancy female rats were fed a liquid diet containing either ethanol [designated as ethanol-fed group (EFG)] or an isocaloric amount of carbohydrate [designated as pair-fed group (PFG)] from gestational day 2 up to delivery. Daily diet ingestion, body weight, nitrogen balance, and nitrogen digestibility were assessed during the gestational period. Crypt and villus cell population, crypt cell proliferation, and crypt cell cycle time were measured in the maternal small intestine at the time animals were killed, just after delivery. Ethanol consumption resulted in ileal hypoplasia of the crypt and villus, but only the villus showed hypoplasia in the jejunum. In addition, crypt cell proliferation was markedly decreased, whereas crypt cell cycle time was longer, both in the jejunum and ileum of the EFG. Ethanol ingestion had no significant effect on body weight gain, nitrogen balance, and nitrogen digestibility. According to our expectations, the offspring from the EFG had significantly lower body weight. In conclusion, chronic ethanol ingestion during pregnancy inhibited the maternal intestinal epithelium growth, more extensively in the ileum.

Time course of nitric oxide production after endotoxin challenge in mice.

Nitric oxide (NO) regulates numerous processes during endotoxemia and inflammation. However, the sequential changes in whole body (Wb) nitric oxide (NO) production during endotoxemia in vivo remain to be clarified. Male Swiss mice were injected intraperitoneally with saline (control group) or lipopolysaccharide (LPS group). After 0, 2, 4, 6, 9, 12, and 24 h, animals received a primed constant infusion of L-[guanidino-(15)N(2)-(2)H(2)]arginine, L-[ureido-(15)N]citrulline, L-[5-(15)N]glutamine, and L-[ring-(2)H(5)]phenylalanine in the jugular vein. Arterial blood was collected for plasma arginine (Arg), citrulline (Cit), glutamine (Gln), and phenylalanine (Phe) concentrations and tracer-to-tracee ratios. NO production was calculated as plasma Arg-to-Cit flux, Wb de novo Arg synthesis as plasma Cit-to-Arg flux, and Wb protein breakdown as plasma Phe flux. LPS reduced plasma Arg and Cit and increased Gln and Phe concentrations. Two peaks of NO production were observed at 4 and 12 h after LPS. Although LPS did not affect total Arg production, de novo Arg production decreased after 12 h. The second peak of NO production coincided with increased Wb Cit, Gln, and Phe production. In conclusion, the curve of NO production in both early and late phases of endotoxemia is not related to plasma Arg kinetics. However, because Wb Cit, Gln, and Phe fluxes increased concomitantly with the second peak of NO production, NO production is probably related to the catabolic phase of endotoxemia.

Effects of ethanol on gut-associated lymphoid tissues in a model of bacterial translocation: a possible role of apoptosis.

Chronic ethanol intake has been shown to be associated with immune suppression and impairment of epithelial barrier function. We investigated the effects of ethanol on intestinal immunity and its relation to bacterial translocation (BT). Male Wistar rats were assigned to one of three groups and received respective diets for 28 days. The ethanol-fed group [(EG); n=11] received a liquid diet containing 5% [volume/volume (vol./vol.)] ethanol; a pair-fed group [(PFG); n=11] received an isocaloric diet without ethanol; and a third (control) group [(CG); n=11] received water and chow ad libitum. On experimental day 29, animals in the EG and the PFG underwent distal ileum ligature and small intestine inoculation of a tetracycline-resistant Escherichia coli strain (TcR E. coli R6), by means of gastric intubation, followed by duodenal ligature. One hour after inoculation, mesenteric lymph nodes, right lobe of liver, spleen, and left kidney were excised for bacterial studies. Sections of jejunum and colon were immunostained, with the use of antibodies against immunoglobulin (Ig) A, T cells, macrophages, and proliferating cell nuclear antigen (PCNA). Apoptosis was determined by the terminal deoxynucleotidyltransferase TdT-mediated dUDP-biotin nick end labeling (TUNEL) method. Bacterial translocation rates were greater in the PFG compared with findings for the EG. Lamina propria of the jejunum of the EG showed a reduction in the densities of IgA+ cells and T cells compared with findings for the PFG and the CG. Colonic lamina propria of the EG showed reduced densities of IgA+ cells and macrophages compared with findings for the PFG and the CG. Apoptotic index was increased in the EG compared with findings for the PFG and the CG, in both jejunum and colon. Proliferation index was not significantly different among groups. Results of the current study show that chronic ethanol ingestion led to a reduction of cellular and humoral components of the intestinal mucosa, possibly by cell loss as a result of ethanol-induced apoptosis. The reduced rates of BT observed after chronic ethanol intake seem to indicate that factors irrespective of immune function might be involved in BT inhibition.

Long chain fatty acid uptake by human intestinal mucosa in vitro: mechanisms of transport.

BACKGROUND/AIMS: The aim of this study was to investigate whether a carrier-mediated membrane transport for long chain fatty acid (LCFA) exists in the human intestinal mucosa. METHODS: Biopsies obtained from the small intestine of patients, during routine endoscopies, were incubated for different periods in the presence of [(3)H]oleic acid complexed to albumin, and lipid fractions were separated and quantified. Biopsies were also incubated during 5 min in different oleic acid:albumin molar ratios. The effect of temperature on lipid transport was tested by incubating biopsies at 37 and 4 degrees C. RESULTS: Maximum [(3)H]oleic acid uptake occurred at 15 min. With increasing unbound oleic acid concentrations in the medium, LCFA uptake during 5 min of incubation revealed a typical saturation kinetics profile, and exhibiting apparent K(m) values of 3.43 +/- 0.83 microM, and apparent V(max) values of 0.86 +/- 0.07 nmol x min(-1) x mg(-1). Within this period, nearly all intracellular fatty acid remained in the unesterified form. The system was also temperature-dependent, having shown a significant reduction of 78.03% in [(3)H]oleic acid uptake at 4 degrees C, in 5 min of incubation. CONCLUSIONS: Our data confirm that LCFA uptake by human intestinal mucosa is likely to occur via a saturable carrier.

Measuring whole-body actin/myosin protein breakdown in mice using a primed constant stable isotope-infusion protocol.

To measure actin/myosin protein breakdown, the 24 h excretion of N (tau)-methylhistidine (3MH) is used. However, in mice, this method is invalid. Therefore we have developed a liquid chromatography-MS technique to measure the tracer/tracee ratio and concentration of 3MH in plasma, enabling an in vivo primed constant infusion protocol with a deuterated stable isotope of 3MH. We tested this model by giving a primed constant infusion of L-[3-methyl-(2)H(3)]histidine, L-[phenyl-(2)H(5)]phenylalanine and L-[phenyl-(2)H(2)]tyrosine to three anaesthetized experimental groups: mice receiving saline intraperitoneally (i.p.) (CON), mice receiving saline i.p. and starved for 9 h (STA), and mice receiving lipopolysaccharide i.p. and starved for 9 h (STA+LPS). The contribution of myofibrillar to total protein breakdown was significantly lower in the STA group than the CON group (30+/-4% and 54+/-14% respectively; P <0.05), and was significantly higher in the STA+LPS group than the STA group (52+/-7% and 30+/-4% respectively; P <0.05). Whole-body myofibrillar protein breakdown, total protein breakdown, protein synthesis and net protein breakdown were not different between the groups. We conclude that this in vivo primed constant stable isotope-infusion protocol can give valuable information about the role of actin/myosin protein breakdown in mice.

[Evaluation of the nutritional status and physical performance in candidates to liver transplantation]. / Avaliação da capacidade física e do estado nutricional em candidatos ao transplante hepático.

OBJECTIVE: To evaluate the physical capacity and nutritional status of patients before orthotopic liver transplantation (OLT) and to correlate these parameters to the severity of liver function. METHODS: Thirty-two patients before OTL were classified as Child-Pugh A (25%), B (22%) and C (53%). Physical capacity was analyzed by the quadriceps and ankle strength, balance, coordination, gait velocity, 6 minute walk test, get up and go test, Barthel and Karnofsky indexes. Nutritional status was evaluated by using Mendenhall score and Blackburn classification. RESULTS: Quadriceps weakness was found in 32% of the patients. Impaired balance and coordination were detected in 34.8% and 15.6% of the patients. Low physical performance was found in 72.5% of the patients (6 min walk test: 31.6% severely; 40.9% moderately impaired) and 43.8% required considerable assistance when the Karnofsky index was applied. Malnutrition was found in 62.5% of the patients (34.37% moderately and severely malnourished and 28.13% mildly malnourished). Chi-square analysis showed no association between Child-Pugh classification and nutritional status, the 6 min walk test and Karnofsky index. The association between the two functional tests was statistically significant (p<0.001). CONCLUSION: The results show that physical impairment and nutritional deficit were highly prevalent in the patients studied, independent of the degree of hepatic dysfunction evaluated by the traditional Child-Pugh classification.

Avaliação da capacidade física e do estado nutricional em candidatos ao transplante hepático / Evaluation of the nutritional status and physical performance in candidates to liver transplantation

OBJETIVO: Avaliar o estado nutricional, os indicadores de capacidade física e suas relações com a função hepática, em pacientes candidatos ao transplante de fígado. MÉTODOS: Foram estudados 32 pacientes pré-transplante, classificados como Child-Pugh A (25 por cento), B (22 por cento) e C (53 por cento). A capacidade física foi avaliada pelos parâmetros: força muscular do quadríceps, dos flexores plantares e dorsais do pé; equilíbrio estático; coordenação; velocidade da marcha; teste de 6 minutos de caminhada e teste "timed get up and go"; índices de Barthel e de Karnofsky. O estado nutricional foi avaliado pelo escore de Mendenhall e classificado segundo Blackburn. RESULTADOS: Foi detectado déficit de força de quadríceps (32 por cento dos pacientes), do equilíbrio (34,8 por cento), da velocidade da marcha (66,7 por cento) e da coordenação (15,6 por cento). O teste de caminhada indicou baixo desempenho físico em 72,5 por cento dos pacientes (moderado em 40,9 por cento e grave em 31,6 por cento). O índice de Karnofsky revelou que 43,8 por cento dos pacientes necessitava assistência considerável. Foi identificada desnutrição em 62,5 por cento dos pacientes (leve em 28,13 por cento; moderada e grave em 34,37 por cento). O teste do qui quadrado não mostrou associação entre a classificação de Child-Pugh e o estado nutricional, o teste de caminhada e o índice de Karnofsky. A associação entre o teste de caminhada e o índice de Karnofsky foi altamente significante (p<0,001). CONCLUSÃO: Os resultados monstraram que a incapacidade física e a desnutrição foram altamente prevalentes nos pacientes estudados, independente do grau da disfunção hepática avaliada segundo a classificação tradicional de Child-Pugh

Lack of adaptation to severe malnutrition in elderly patients.

BACKGROUND & AIMS: Sarcopenia is a common feature in the healthy elderly. However, little is known on age-related modifications of body composition in malnourished patients. The aims of this cross-sectional study were to evaluate the effects of aging per se on body composition and resting energy expenditure (REE) in malnourished patients. METHODS: Ninety-seven non-stressed patients referred for chronic malnutrition (C-reactive protein <5 mg/l) were separated into two groups: middle-aged (26 female, 19 male, 48+/-15 yr), and elderly (26 female, 26 male, 79+/-6 yr). Body composition was assessed by bioelectrical impedance analysis and REE by indirect calorimetry. RESULTS: In middle-aged patients, body composition remained stable between moderate (body-mass index [BMI; in kg/m(2)] 16-18.5) and severe (BMI < 16) malnutrition, with similar values of fat-free mass (FFM), body cell mass (BCM) and fat mass (FM) as percentages of body weight, whereas in elderly patients malnutrition occurred at the expense of FFM and BCM, with unchanged FM absolute values. REE/FFM values remained stable in middle-aged patients at every stage of malnutrition, whereas they increased in elderly patients along with their degree of malnutrition. In multivariate analysis, both body composition and REE/FFM were influenced by sex, age, BMI and mid-arm circumference. CONCLUSION: Compared to younger patients, weight loss in the elderly leads to cachexia, with a preferential loss of FFM and BCM that may participate in the more severe outcomes observed in these patients. They also show elevated REE/FFM values that induce higher energy needs.