Role of dietary fatty acids in mammary gland development and breast cancer

Breast cancer is the most common cancer among women worldwide. Estimates suggest up to 35% of cases may be preventable through diet and lifestyle modification. Growing research on the role of fats in human health suggests that early exposure in life to specific fatty acids, when tissues are particularly sensitive to their environment, can have long-term health impacts. The present review examines the role of dietary fat in mammary gland development and breast cancer throughout the lifecycle. Overall, n-3 polyunsaturated fatty acids have promising cancer-preventive effects when introduced early in life, and warrant further research to elucidate the mechanisms of action

Autonomic activation links CNS oxygen toxicity to acute cardiogenic pulmonary injury

Breathing hyperbaric oxygen (HBO2), particularly at pressures above 3 atmospheres absolute, can cause acute pulmonary injury that is more severe if signs of central nervous system toxicity occur. This is consistent with the activation of an autonomic link between the brain and the lung, leading to acute pulmonary oxygen toxicity. This pulmonary damage is characterized by leakage of fluid, protein, and red blood cells into the alveoli, compatible with hydrostatic injury due to pulmonary hypertension, left atrial hypertension, or both. Until now, however, central hemodynamic parameters and autonomic activity have not been studied concurrently in HBO2, so any hypothetical connections between the two have remained untested. Therefore, we performed experiments using rats in which cerebral blood flow, electroencephalographic activity, cardiopulmonary hemodynamics, and autonomic traffic were measured in HBO2 at 5 and 6 atmospheres absolute. In some animals, autonomic pathways were disrupted pharmacologically or surgically. Our findings indicate that pulmonary damage in HBO2 is caused by an abrupt and significant increase in pulmonary vascular pressure, sufficient to produce barotrauma in capillaries. Specifically, extreme HBO2 exposures produce massive sympathetic outflow from the central nervous system that depresses left ventricular function, resulting in acute left atrial and pulmonary hypertension. We attribute these effects on the heart and on the pulmonary vasculature to HBO2-mediated central sympathetic excitation and catecholamine release that disturbs the normal equilibrium between excitatory and inhibitory activity in the autonomic nervous system

Role of stearoyl-CoA desaturases in obesity and the metabolic syndrome.

The prevalence of obesity and related metabolic disorders increases rapidly in western societies. A proper choice of foods may now prevent or delay many of the health consequences related to these disorders. In this respect, replacing dietary saturated fatty acids (SFAs) by cis-monounsaturated fatty acids (cis-MUFAs) has beneficial effects. In addition to diet-derived cis-MUFAs, the human body can also generate cis-MUFAsfrom SFAs through the action of stearoyl-CoA desaturases (SCDs). SCDs may play an adverse role in obesity and obesity-related insulin resistance. Here, we review the current knowledge on the molecular aspects and the role of SCD1 in obesity and the metabolic syndrome (MS). In mice, many studies have suggested a negative role for SCD1 in the development of obesity and insulin resistance. In humans, however, evidence is less convincing. If anything, increased, rather than decreased, levels of SCD1 mRNA levels are negatively associated with MS-related diseases such as insulin resistance. However, an unequivocal conclusion is currently not possible as the number of human studies is limited. Therefore, more human studies are needed at the molecular as well as at the physiological level to understand the true role of SCD1 during the development of obesity and the MS.International Journal of Obesity advance online publication, 22 April 2008; doi:10.1038/ijo.2008.5