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Synthetic cannabinoid use elicits “zombie-like” symptoms in New York.

Although most think of type 2 diabetes (T2D) as a disease of glucose metabolism dysfunction, abnormal lipid metabolism is actually the underlying cause of this common disease. Under conditions of energy excess, the liver and skeletal muscle accumulate intermediates in the lipid biosynthetic pathway

Elevated low-density lipoprotein cholesterol (LDL-C) is a major risk factor for cardiovascular disease (CVD). Mutations in the receptor that clears circulating LDL-C result in a devastating condition known as familial hypercholesterolemia (FH), which is characterized by extremely high levels of LDL-C and markedly accelerated CVD mortality. Recently, the United States Food and Drug Administration approved a somewhat controversial new therapy called mipomersen for patients suffering from FH. Mipomersen is one of the first antisense oligonucleotide (ASO)–based therapies that specifically targets the knockdown of the major structural protein of LDL-C known as apolipoprotein B (apoB). Given the central role that apoB plays in removing lipids such as cholesterol and triglycerides from the liver, many experts in the field warned that hepatic steatosis (i.e., fatty liver) would be an obvious potential side effect of this drug. However, both rodent and human studies have shown that mipomersen treatment paradoxically does not result in hepatic steatosis, though the mechanisms behind this have been elusive. Now, Conlon et al. provide evidence in mice that ASO-mediated knockdown of apoB stimulates a compensatory up-regulation of endoplasmic reticulum (ER)–associated autophagy, functionally channeling triglycerides towards lysosomal degradation. To identify mechanisms by which mipomersen fails to induce hepatic steatosis, Conlon et al. treated mice with a mouse-targeted apoB ASO and carefully examined subcellular accumulation of lipids, as well as markers of autophagic flux in the liver. In early stages of apoB knockdown, there was an apparent activation of ER stress and accumulation of autophagosome-like structures. As treatment was prolonged, activation of ER-associated autophagy was coupled to increased lipolysis of triglycerides, which ultimately resulted in delivery of fatty acid substrate for mitochondrial oxidation. This study provides insights into a compensatory pathway in the liver that senses abnormal accumulation of triglycerides in the ER to activate lysosomal triglyceride degradation. This important work reveals molecular mechanisms regulating hepatic triglyceride storage and secretion and provides a long-awaited explanation for why mipomersen does not promote hepatic steatosis. D. M. Conlon et al. , Inhibition of apolipoprotein B synthesis stimulates endoplasmic reticulum autophagy that prevents steatosis. J. Clin. Invest. 10.1172/JCI86028 (2016). [[Full Text]][1] [1]: https://www.jci.org/articles/view/86028

The human intestine is home to trillions of bacteria, which in some estimates outnumber host cells in the body. Emerging evidence suggests that resident intestinal microbial communities not only enable us to efficiently harvest energy from our food but also function as an underappreciated endocrine

It has long been understood that what we eat contributes directly to our risk of developing diseases from obesity to diabetes to heart disease. An emerging question in this field is whether our own poor dietary choices can affect the health of our offspring through diet-driven epigenetic

Atherosclerosis and associated coronary heart disease (CHD) remain the largest cause of mortality in developed countries. Statins have been life-saving drugs for many, but CHD-associated mortality and morbidity have only been modestly reduced, demonstrating a clear need for additional therapeutic

The expansion of adipose tissue in obese individuals is closely associated with the development of a number of chronic diseases, including diabetes, cardiovascular disease, and certain types of cancer. Thus, there is a clear unmet need for effective obesity therapies. Recent studies have deciphered distinct types of adipose tissues (white, brown, and beige) that differentially affect energy homeostasis. Such discoveries about human physiology have the potential to pinpoint new therapeutic targets. In this vein, Lee et al. demonstrate an underappreciated circadian rhythm associated with the glucose-fueled activity of brown adipose tissue (BAT). Classic white adipose tissue functions primarily as a depot to store energy, whereas brown adipose tissue (BAT) and the recently described beige adipose tissue function to burn energy and generate heat through a process called nonshivering thermogenesis. It has long been assumed that adult humans do not have enough measurable thermogenic brown or beige adipose tissue to have an impact on energy expenditure, and this assumption has dampened enthusiasm for drug discovery in this area. However, a recent series of high-profile papers that demonstrate the existence of BAT in adult humans has sparked a revival in the field. Although there are still many detractors, the prevailing hypothesis is that therapeutic strategies that convert classic white adipose tissue into beige or brown adipose tissue could be effective in the treatment of obesity-related disorders. Brown adipose tissue is typically thought to protect the body from cold temperatures via its key role in nonshivering thermogenesis. As a surrogate for BAT-driven thermogenesis, the authors measured supraclavical skin temperature in human subjects under both cold-stressed (14o to 18oC) and thermoneutral (24oC) conditions. Skin temperature correlated with 18F-deoxyglucse (FDG)–positron emission tomography measurements in human BAT. The authors also demonstrated that human BAT activity increased during an oral glucose tolerance test and provided evidence that BAT can use glucose as a thermogenic fuel. By following supraclavical skin temperature over a 12-hour period in subjects stratified for low and high BAT activity, the author uncovered a circadian-like rhythmicity associated with BAT glucose utilization. This circadian rhythm of glucose metabolism was maintained in cultured human brown adipocytes, indicating that a cell-autonomous clock exists to regulate delivery of glucose to thermogenic brown adipocytes. These findings have uncovered a previously underappreciated role for BAT in controlling systemic circadian and meal-related fluctuations in glycemia. It is likely that strategies for stimulating BAT-driven thermogenesis hold promise for the discovery and development of obesity therapeutics, but additional research is required to understand how this circadian circuit aligns with the well-documented ability of BAT to consume fatty acids for thermogenic fuel. Although it was long assumed that BAT-driven thermogenesis was relevant only in rodents, new findings in human subjects and isolated tissues now stoke the fire for research on BAT-targeted therapeutics. P. Lee et al ., Brown adipose tissue exhibits a glucose-responsive thermogenic biorhythm in humans. Cell Metab . 10.1016/j.cmet.2016.02.007 (2016). [[Abstract]][1] [1]: http://www.cell.com/cell-metabolism/abstract/S1550-4131(16)30056-0