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Although it is now accepted that adult humans possess active brown adipose tissue, it has been questioned whether this is genuine classical brown adipose tissue. Two new studies provide evidence that humans, both as babies and adults, do have classical brown tissue and also indicate that there is heterogeneity in the composition of brown fat depots in humans, as in mice (pages 631–634 and 635–639).
The publication of a controversial study by a US National Institutes of Health (NIH)-funded researcher suggesting a link between the Tea Party and the tobacco industry has brought the NIH under fire by Congress. But strict policing of NIH grantees would be a waste of resources and a setback to scientific inquiry.
The RAS-RAF-MEK-ERK signaling kinase pathway has been the focus of intense cancer drug development efforts because of its central role in tumor cell proliferation and survival. Although inhibitors of RAF and MEK provide therapeutic validation, tumor resistance challenges their effectiveness. Targeting scaffolding proteins such as IQGAP1 may be a new approach (pages 626–630).
It has long been unknown how activation of resident macrophages in the brain, or microglia, is regulated during the inflammatory pathogenesis of multiple sclerosis. Work in a mouse model of human multiple sclerosis identifies the E3 ubiquitin ligase Peli1 as a new crucial regulator of microglia activation (pages 595–602).
Mandana Arabi leads the Sackler Institute for Nutrition Science, created in 2011 by the New York Academy of Sciences to address the massive global problem of malnutrition. She spoke with Alisa Opar about how the institute hopes to put nutrition research on the scientific map.
L-Carnitine is a common food supplement and naturally occurs in red meat. This nutrient is metabolized into trimethyl metabolites by the gut microbiota and is associated with an elevated risk for cardiovascular disease. A recent study provides new insights into this link by exploring how the gut microbiota generates proatherogenic metabolites from L-carnitine and how the microbiota is altered in response to an omnivorous diet (pages 576–585).