Control of adipogenesis by fatty acids

A obesidade é um dos principais problemas de saúde pública. Indivíduos obesos são mais suscetíveis a desenvolver doenças cardiovasculares e diabetes melito tipo 2. A obesidade resulta do aumento no tamanho e no número de adipócitos. O balanço entre adipogênese e adiposidade determina o grau de obesidade do indivíduo. Adipócitos maduros secretam adipocinas, tais como TNFα, IL-6, leptina e adiponectina, e lipocina, o ácido palmitoleico ω-7. A produção de adipocinas é maior na obesidade, o que contribui para o estabelecimento de resistência periférica à insulina. O conhecimento dos eventos moleculares que regulam a diferenciação dos pré-adipócitos e de células-tronco mesenquimais em adipócitos (adipogênese) é importante para o entendimento da gênese da obesidade. A ativação do fator de transcrição PPARγ é essencial na adipogênese. Certos ácidos graxos são ligantes de PPARγ e podem, assim, controlar a adipogênese. Além disso, alguns ácidos graxos atuam como moléculas sinalizadoras em adipócitos, regulando sua diferenciação ou morte. Dessa forma, a composição lipídica da dieta e os agonistas de PPARγ podem regular o balanço entre adipogênese e morte de adipócitos e, portanto, a obesidade.Obesity is one of the major Public Health problems. Obese individuals are more susceptible to develop cardiovascular diseases and type 2 diabetes mellitus. The obesity results from the increase in size and number of the adipocytes. The balance between adipogenesis and adiposity determines the degree of obesity. Mature adipocytes secrete adipokines, such as TNFα, IL-6, leptine and adiponectin, and lipokine, the palmitoleic acid ω-7. The production of adipokines is increased in obesity, contributing to the onset of peripheral insulin resistance. The knowledge about the molecular events that regulate the differentiation of pre-adipocytes and mesenchymal stem cells into adipocytes (adipogenesis) is important for the comprehension of the genesis of obesity. Activation of transcription factor PPARγ plays an essential role in the adipogenesis. Certain fatty acids are PPARγ ligands and can control adipogenesis. Moreover, some fatty acids act as signaling molecules regulating their differentiation into adipocytes or death. Accordingly, the lipid composition of the diet and PPARγ agonists can regulate the balance between adipogenesis and death of adipocytes and, therefore, the obesity

Incidência de fraturas ósseas dos membros inferiores em indivíduos do sexo feminino de Aracaju (Sergipe), Brasil

Studies indicate that the number of hip bone fractures caused by osteoporosis may rise from 1.66 to 6.26 million until 2050, worldwide. For this reason, implementation of preventive measures becomes a necessity. Female individuals are usually more affected due to a variety of factors including old age, early menopause, chronicle disease in the family history, calcium deficit, as well as the lack of physical exercise (sedentary individual). The aim of this study was to estimate the incidence of hip and lower limb\ud fracture in female individuals’ resident in Aracaju city. From the period of January 2008-2009, around of 300 fracture cases were of lower limb analyzed from females. The incidence of femur fractures in women increased according to age group, 66.17 individuals per 10,000 inhabitants (over 60 years-old). These findings allow us to conclude that the incidence of hip and lower limb bone fractures among women over 60 years were more significant in the femur.CAPESCNPqFAPITEC/S

Intrauterine food restriction impairs the lipogenesis process in the mesenteric adipocytes from low-birth-weight rats into adulthood

BackgroundIntrauterine food restriction (IFR) during pregnancy is associated with low birth weight (LBW) and obesity in adulthood. It is known that white adipose tissue (WAT) plays critical metabolic and endocrine functions; however, this tissue’s behavior before weight gain and obesity into adulthood is poorly studied. Thus, we evaluated the repercussions of IFR on the lipogenesis and lipolysis processes in the offspring and described the effects on WAT inflammatory cytokine production and secretion.MethodsWe induced IFR by providing gestating rats with 50% of the necessary chow daily amount during all gestational periods. After birth, we monitored the offspring for 12 weeks. The capacity of isolated fat cells from mesenteric white adipose tissue (meWAT) to perform lipogenesis (14C-labeled glucose incorporation into lipids) and lipolysis (with or without isoproterenol) was assessed. The expression levels of genes linked to these processes were measured by real-time PCR. In parallel, Multiplex assays were conducted to analyze pro-inflammatory markers, such as IL-1, IL-6, and TNF-α, in the meWAT.ResultsTwelve-week-old LBW rats presented elevated serum triacylglycerol (TAG) content and attenuated lipogenesis and lipolysis compared to control animals. Inflammatory cytokine levels were increased in the meWAT of LBW rats, evidenced by augmented secretion by adipocytes and upregulated gene and protein expression by the tissue. However, there were no significant alterations in the serum cytokines content from the LBW group. Additionally, liver weight, TAG content in the hepatocytes and serum glucocorticoid levels were increased in the LBW group.ConclusionThe results demonstrate that IFR throughout pregnancy yields LBW offspring characterized by inhibited lipogenesis and lipolysis and reduced meWAT lipid storage at 12 weeks. The increased serum TAG content may contribute to the augmented synthesis and secretion of pro-inflammatory markers detected in the LBW group

Impaired glucose tolerance in low-carbohydrate diet: maybe only a physiological state

Conselho Nacional de Desenvolvimento da Pesquisa (National Council of Research Development) - 476148/2010-3Fundação de Amparo à Pesquisa do Estado de Sao Paulo (Sao Paulo State Research Foundation) - 10/00246-