Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Mais filtros

Filtros aplicados

Base de dados
Intervalo de ano de publicação
FASEB J ; 14(13): 2040-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11023988


The intestinal fatty acid binding protein (I-FABP) belongs to a family of 15 kDa clamshell-like proteins that are found in many different tissues. So far, nine types have been identified. Their primary structures are highly conserved between species but somewhat less so among the different types. The function of these proteins, many of which are highly expressed, is not well understood. Their ability to bind lipid ligands suggests a role in lipid metabolism, but direct evidence for this idea is still lacking. We tested the hypothesis that I-FABP serves an essential role in the assimilation of dietary fatty acids by disrupting its gene (Fabpi) in the mouse. We discovered that Fabpi-/- mice are viable, but they display alterations in body weight and are hyperinsulinemic. Male Fabpi-/- mice had elevated plasma triacylglycerols and weighed more regardless of the dietary fat content. In contrast, female Fabpi-/- mice gained less weight in response to a high-fat diet. The results clearly demonstrate that I-FABP is not essential for dietary fat absorption. We propose that I-FABP functions as a lipid-sensing component of energy homeostasis that alters body weight gain in a gender-specific fashion.

Proteínas de Transporte/metabolismo , Gorduras na Dieta/metabolismo , Absorção Intestinal , Proteínas de Neoplasias , Proteínas do Tecido Nervoso , Animais , Glicemia/análise , Alterações do Peso Corporal , Proteínas de Transporte/genética , Proteína 7 de Ligação a Ácidos Graxos , Proteínas de Ligação a Ácido Graxo , Feminino , Insulina/sangue , Lipídeos/sangue , Masculino , Camundongos , Camundongos Mutantes , Fatores Sexuais
Pediatr Res ; 48(3): 380-3, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10960507


Leptin (OB protein) elicits a neuroendocrine response to starvation and states of nutritional abundance to stabilize the proportion of body fat. Leptin has dramatic effects on food intake and energy expenditure in adult and juvenile rodents. However, whether the neonatal period is associated with the development of an effective leptin feedback system is still not known. In this study, we evaluated the effects of peripherally administered leptin on body weight changes in neonatal rats during the early suckling period (from birth to 10 d). Our results show that daily i.p. injections of leptin (0.3 microg/g and 1.0 microg/g) to neonatal rats led to a significant reduction in weight gain over 10 d compared with the control group (p < 0.01 and p < 0.01, respectively). Concomitant with a reduction in weight gain, retroperitoneal fat pad weight also significantly decreased in the leptin-treated group. Our data indicate that the potential for energy balance regulation by leptin occurs in the first day after birth. In addition, we also observed that 3 d after discontinuing leptin treatment, the body weight as well as the fat pad weight of leptin-treated pups returned to the control level. Our results demonstrate that leptin reduces body weight gain in neonatal rats.

Peso Corporal/efeitos dos fármacos , Leptina/administração & dosagem , Animais , Animais Recém-Nascidos , Alterações do Peso Corporal , Injeções Intraperitoneais , Ratos , Ratos Sprague-Dawley
JAMA ; 282(22): 2136-42, 1999 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-10591335


CONTEXT: The mean body weight of US adults increased by 3.6 kg (7.6 lb) during the past 15 years, but few studies exist that examine the impact of such weight change on functional health status. OBJECTIVE: To investigate, prospectively, the association between weight change and health-related quality of life in women. DESIGN AND SETTING: Nurses' Health Study, a 4-year prospective observational study from 1992 to 1996, using the Medical Outcomes Study Short-Form 36 Health Status Survey (a self-administered 36-item questionnaire) to measure quality of life. PARTICIPANTS: A cohort of 40098 women (from 46-71 years old in 1992) grouped according to 3 patterns of weight change over the 4-year period: women whose weight remained within 2.25 kg (5 lb) of their baseline weight, women who lost 2.25 kg (5 lb) or more, and women who gained 2.25 kg (5 lb) or more. MAIN OUTCOME MEASURES: Change in scores on 7 health-related quality-of-life dimensions: physical functioning, vitality, bodily pain, limitations in role functioning due to emotional or physical problems, social functioning, and mental health, measured by the Short-Form 36 Health Status Survey. RESULTS: A total of 15602 women (39%) maintained their weight, 15160 (38%) gained between 2.25 and 9.0 kg (5-20 lb), and 6667 (17%) lost between 2.25 and 9.0 kg (5-20 lb). Weight gain was associated with decreased physical function and vitality, and increased bodily pain regardless of baseline weight. For example, the odds ratio for developing role limitations due to physical problems was 2.05 (95% confidence interval, 1.69-2.49) for the leanest women who gained 9.0 kg (20 lb) or more. Weight loss in overweight women was associated with improved physical function and vitality as well as decreased bodily pain. Weight change was more strongly associated with physical rather than mental health. The impact of weight change, especially weight gain, was just as strong in women 65 years and older as in women younger than 65 years. CONCLUSIONS: These longitudinal data support current US guidelines for women of all body mass index levels to avoid weight gain. Weight maintenance and, in cases of overweight, weight loss are desirable and likely to be beneficial for physical function, vitality, and bodily pain.

Alterações do Peso Corporal , Nível de Saúde , Qualidade de Vida , Idoso , Índice de Massa Corporal , Feminino , Inquéritos Epidemiológicos , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Estudos Prospectivos , Estados Unidos/epidemiologia , Ganho de Peso , Perda de Peso , Saúde da Mulher
J Womens Health Gend Based Med ; 8(10): 1265-72, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10643834


Postmenopausal overweight women have an increased risk of breast cancer. The link between obesity and breast cancer could be mediated through hyperinsulinemia. Insulin and insulin-like growth factor-1 (IGF-1) stimulate mammary cell proliferation in vitro, and cell proliferation is directly linked to the risk of breast cancer. Our objective was to investigate the relationship between breast cancer and body composition, IGF-1, proinsulin, C-peptide, and fasting insulin. A case-control study was conducted of 438 community-dwelling women aged 53-90 years in 1992-1994 who had no history of cancer at the baseline visit in 1972-1974. Women were excluded who were using estrogen replacement therapy (ERT) or tamoxifen at the 1992-1994 visit, when IGF-1, proinsulin, fasting insulin, and C-peptide levels were measured. Prior ERT, alcohol and tobacco use, exercise, and reproductive history were recorded. Weight, height, and waist/hip ratio were measured. The 45 women with breast cancer had similar baseline body mass indices to the 393 women without breast cancer but had gained significantly more weight between the baseline visit in 1972-1974 and 1992-1994, (age-adjusted relative risk [RR] 1.05/kg, 95% confidence interval [CI] 1.01-1.09, p = 0.016). Proinsulin, fasting insulin, and C-peptide were each significantly positively correlated with both current weight and weight gain. However, levels of these hormones and IGF-1 did not differ significantly between women with and without breast cancer (all 95% CI within 0.996-1.004). Past ERT was significantly more common among women with breast cancer (p = 0.015), and duration of use was significantly longer (age-adjusted RR 1.13 per year of use, 95% CI 1.08-1.18, p = 0.000). The risk of breast cancer was significantly increased in women who had gained weight or used ERT. This increased risk was not associated with circulating levels of IGF-1, fasting insulin, proinsulin, or C-peptide.

Alterações do Peso Corporal , Neoplasias da Mama/sangue , Peptídeo C/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Insulina/sangue , Obesidade/sangue , Proinsulina/sangue , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/etiologia , Estudos de Casos e Controles , Terapia de Reposição de Estrogênios , Feminino , Seguimentos , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Obesidade/complicações , Fatores de Risco