Metabolic Syndrome Pathophysiology and Predisposing Factors.

Metabolic syndrome (MetS) is a cluster of cardiometabolic risk factors with high prevalence among adult populations and elevated costs for public health systems worldwide. Despite the lack of consensus regarding the syndrome definition and diagnosis criteria, it is characterized by the coexistence of risk factors such as abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, a prothrombotic and pro-inflammatory state, insulin resistance (IR), and higher glucose levels, factors indubitably linked to an increased risk of developing chronic conditions, such as type 2 diabetes (T2D) and cardiovascular disease (CVD). The syndrome has a complex and multifaceted origin not fully understood; however, it has been strongly suggested that sedentarism and unbalanced dietary patterns might play a fundamental role in its development. The purpose of this review is to provide an overview from the syndrome epidemiology, costs, and main etiological traits from its relationship with unhealthy diet patterns and sedentary lifestyles.

Islets of Langerhans phenotype alterations induced by fatty diet and physical activity levels in Wistar rats.

OBJECTIVES: Physical inactivity (PIn) and a fatty diet (FD) are closely linked to development of metabolic syndrome (MetS), overloading the endocrine pancreas seeking energy homeostasis. However, the relative contribution of FD and PIn to the pancreatic overload is unknown. The aim of this study was to verify the isolated and conjugated influence of FD and PIn in the islets of Langer hans (islets) structure and function related to overload in Wistar rats. METHODS: Male Wistar rats were divided into four groups (n = 10/group): active groups, fed with fat (AFD) or standard (ASD) diet; and physically inactive groups, fed with fat (SFD) or standard (SSD) diet for 21 wk. Glucose tolerance (GT) and insulin sensitivity (IS) were assessed before sacrifice. Retroperitoneal adipose tissue and pancreas were weighted (PW), and pancreas samples processed for histologic analyses. RESULTS: Only the FD-fed animals presented MS. Compared with standard diet, FD impaired GT and IS, decreased PW, and enlarged islets dimensions, with islets cellular death, inflammatory response, and enhanced collagen content, which were attenuated in AFD. Independent of the diet, PIn groups presented higher amounts of islets connective tissue, but without influence on inflammatory reaction and cellular death. The GT impairment was higher in the FD-fed groups, whereas the decreased IS was more pronounced in the PIn groups. CONCLUSION: FD induced MS with detrimental effects on pancreas overload, inducing islets morphologic and functional maladaptation, which were attenuated in active animals. Physical activity was not able to prevent FD-induced MS. FD showed a negative influence on GT, whereas PIn mainly affected IS.

Efeito do treinamento físico moderado e intenso sobre os mecanismos de defesa de ratos adultos / Effect of moderate and intense physical training on the mechanisms of defense in adult rats

OBJETIVO: Analisou-se o impacto do treinamento físico moderado (TFM) e intenso (TFI) sobre o perfil leucocitário e a atividade microbicida de macrófagos alveolares, em 29 ratos machos Wistar. MÉTODOS: Foram formados três grupos: controle-sedentário (CS), treino-moderado (TM) e treino-intenso (TI). Os TFM e TFI foram efetuados através da natação, com aumento progressivo de carga conforme o peso corporal, até um máximo de 3% para o TFM, e 5% para o TFI. As coletas de sangue para contagem total e diferencial dos leucócitos foram automatizadas através do analisador hematológico Sysmex XT- 1800i (Roche®) antes e após o treino. E ao final realizou-se o lavado broncoalveolar para determinar a taxa de fagocitose e a produção de óxido nítrico (ON) de macrófagos. RESULTADOS: O grupo TM apresentou valores maiores para o número de leucócitos (12,77±2,0 x 17,25±2,4 10³/mm³), linfócitos (8,87±1,0 x 12,5±2,1 10³/mm³) e neutrófilos (0,99±0,5 x 3,18±1,0 10³/mm³), p<0,05. Apresentou também uma maior produção de ON (15,77±4,9µmols/mL) e da taxa de fagocitose (38,6%±8,65) em relação ao CS (6,58±1,9µmols/mL e 24,4%±7,40, respectivamente). Enquanto que, o grupo TI apresentou menor taxa de fagocitose (13,1%±1,52 x 24,4%±7,40), maior produção de ON (38,40± 2,1x 6,58±1,9 µmols/mL) e aumento apenas, no valor dos neutrófilos (2,6±1,4x 0,99±0,5 10³/mm³) quando comparado ao CS, p<0,001. CONCLUSÕES: O TFM proporcionou melhora nos mecanismos de defesa dos animais adultos. Enquanto que o TFI reduziu a taxa de fagocitose o que poderá implicar em prejuízo da atividade microbicida dos animais.

OBJECTIVE: To assess the impact of moderate (MPT) and intense physical training (IPT) on the white blood cell profile and the microbicide activity of alveolar macrophages in 29 Wistar male rats. METHODS: The sample was separated into three groups: control group (sedentary), moderate training (MT), and intense training groups (IT). Swimming was the tool used to classify both moderate and intense training groups with a progressive increase of exercise load regarding body weight (up to 3% for the moderate physical training and 5% for the intense training group). The blood samples used to count total and differential leucocytes were automated by a hematological analyzer Sysmex XT-1800i (Roche®) before and after training sessions. At the end of the process, a bronchoalveolar lavage was carried out so to determine the amount of phagocytosis and the production of nitric oxide (NO) of the macrophages. RESULTS: The MT showed an increase in the number of leucocytes (12,77±2,0x17,25±2,4 10³/mm³), lymphocytes (8,87±1,0x 12,5±2,1 10³/mm³) and neutrophils (0,99±0,5x3,18 ±1,0 10³/mm³), p<0,05. There was also a higher production of NO (15,77±4,9µmols/mL) as well as a higher phagocytosis rate of (38,6%±8,65) as to the control group (6,58±1,9 µmols/mL and 24,4%±7,40, respectively). Whereas the IT showed a smaller phagocytosis rate (13,1%±1,52x 24,4%±7,40), a greater production of NO (38,40±2,1 x 6,58±1,9 µmols/mL) and an increase only in the number of neutrophils (2,6±1,4 x 0,99±0,5 10³/mm³) compared to the control group, p<0,001. CONCLUSIONS: The MPT induced a significant improvement in the defense mechanisms of the adult rats. On the other hand, the IPT induced a reduction in phagocytosis rate which could lead to the microbicide activity of the rats being damaged.