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The study is the first to examine all of the gene networks affected by fructose that result in changes to brain function and metabolism-more than 20,000 genes in total. Although the study was conducted using rats, the researchers report that the majority of the sequenced genes are comparable to those in humans, including more than 200 genes in the hippocampus, a brain area crucial to memory, and 700 in the hypothalamus, the seat of the brain's metabolic control center.

Immune cells in mice with lupus symptoms have overactive metabolisms, so scientists inhibited two metabolic pathways and succeeded in reversing lupus symptoms in mice

Cancer cells are hungry. To feed their rapid growth and division, their metabolism changes. Moreover, they use sugar (glucose) in a different way to normal cells. This animation, created by Nature Reviews Drug Discovery, explores the key aspects of the altered metabolism in cancer cells and explains how these can be exploited for the development of new anticancer strategies.

This case study describes the daily osmotic struggle for survival faced by hummingbirds. The narrative is written from the viewpoint of a human observer who sees an Anna's hummingbird feeding on flowers outside of her window.  She notices that the birds mostly feed early in the morning and again in the evening at dusk; midday encounters are rare.  The case raises questions about floral nectar production, how this correlates to feeding bouts, and how this in turn correlates to the daily osmotic challenges faced by these nectarivorous birds and their allies (sunbirds). Students will learn about renal adaptations for survival and how they operate. Finally, since hummingbirds have a high metabolic rate and cannot feed overnight they undergo torpor during this time, an energy saving physiologic state.  Students read journal articles to answer case questions, which should lead them to a better understanding of the related physiological processes of osmoregulation, metabolic rate and torpor.

The study is the first to find that people's bodies metabolize bisphenol-A (BPA) - a chemical found in most people and used in polycarbonate plastic, food cans and paper receipts - into something that impacts our cells and may make us fat. The research, from Health Canada, challenges an untested assumption that our liver metabolizes BPA into a form that doesn't impact our health.

"Millions of people who suffer from less-intense sleep problems do suffer myriad health burdens. In addition to emotional distress and cognitive impairments, these can include high blood pressure, obesity, and metabolic syndrome. And recent research has suggested even mild sleep loss, the kind people often subject themselves to during the work week by watching late-night TV until midnight then rising before dawn, may lead to metabolic, cardiovascular, cognitive, and neurologic dysfunction."

This case study explores the topics of diffusion, osmosis, membrane transport, and the physiological significance of glucose and insulin in the human body. The story begins with a high school athlete, Timmy, who is incredibly efficient at metabolizing carbohydrates for energy; this is where the reader is introduced to normal carbohydrate digestion and metabolism for energy within skeletal muscle cells. As Timmy enters college, he withdraws from sports and physical activity but continues to consume massive amounts of highly soluble carbohydrates, resulting in insulin resistance and ultimately type II diabetes. Throughout the case students are prompted with conceptual questions and interactive figures that require the application and transfer of information they have been introduced to. Originally written for intermediate and advanced physiology courses that cover foundational and complex concepts in science, the case is also appropriate for courses in intermediate biology, nutritional sciences, animal sciences, and exercise sciences.

n this interrupted case study, students learn about the influence of early fetal nutritional conditions on the expression of genes related to metabolism and growth. Beginning with the true event of a food and fuel embargo that led to famine in the western Netherlands toward the end of World War II, students learn about the historical background of the Dutch Hunger Winter and its social impact. Using real data from the study conducted by Heijmans and coauthors (2008), students then compare the methylation level of a specific gene between individuals conceived during the famine and their unaffected siblings, and how changes in the expression of this metabolically important gene may impact the risk of developing type 2 diabetes. Supported by other studies on mice and in humans, students conclude that in utero events may impact the health of individuals later in life through epigenetic mechanisms. The case is ideally suited for a molecular or cell biology course, but is also appropriate for an introductory biology course in which students have an understanding of descriptive statistics, interpretation of statistical test results, eukaryotic gene structure, and regulation of gene expression.

This case study was developed for an introductory biology course with the goal of integrating content (specifically, structure/function, signaling pathways, and homeostasis) while reinforcing general critical thinking skills and the scientific method (generating hypotheses, evaluating evidence, and making predictions). The case is suitable for a flipped classroom and there are several videos associated with it. The case revolves around an obese two-and-a-half-year-old boy who won't stop eating. Students become familiar with some basic concepts related to obesity and leptin signaling through the videos that they watch before class. They then use class time to work through the case (delivered as an interactive slide show, including several clicker questions) to determine the genetic basis for this child's obesity and possible therapies to manage his weight. The case could also be adapted and expanded to be used in a physiology course to explore the interaction of various hormones that regulate appetite and metabolic rate or in a cell biology class to explore JAK-STAT signaling.

In this directed case study students follow a nurse practitioner and work with a diagnostics team to determine what is wrong with Tristan, an infant who comes to the clinic with multiple bruises. Students are given background and patient history, and are then given results of various blood tests ordered by the diagnostics team. The exercise emphasizes the physiological process of coagulation and the importance of various clotting factors, especially factor VIII. Students will be introduced to results from several blood tests, including: complete blood count, partial thromboplastin time, prothrombin time, metabolic panel, and factor VIII assay. The patient is ultimately diagnosed with severe hemophilia A and the case then introduces students to this disorder, the genetic determinants, the incidence, and ways to manage the disease. The data in this case are real and the story represents the medical history of an actual patient. Originally developed for pre-nursing students, this activity would also be suitable for majors in physiology or pre-medical students; it could also be used in an introductory genetics or biology course.

In recent years, Claverie and his colleagues have discovered a host of giant viruses, which are as big as bacteria but lack characteristic cellular machinery and metabolism of those microorganisms. At least one family of these viruses likely evolved from single-celled parasites after losing essential genes, although the origins of other giant viruses remain a mystery, Claverie said.

The groundwater is cold, deep and twice as salty as seawater, but the water streaming out of Blood Falls, which teems with microbes, tells us that it is unlikely to be lifeless. "The fact that the [water] contains metabolically active micro-organisms that appear to be suited to life in a dark, cold brine supports the idea that life should persist throughout the subsurface," says Mikucki. If so, those microbes could be fuelling life in the Southern Ocean. By breaking down iron-containing rocks they might be dumping as much as 170 million kilograms of iron into the ocean each year, according to the researchers' estimates, helping to explain why marine productivity is seasonally very high near to the coast.

The laboratory-based animal study found a link between greater susceptibility to obesity and diabetes, and whether one's ancestors have been undernourished for several generations, and was published on Friday in the journal Cell Metabolism.

The cellular life cycle, also called the cell cycle, includes many processes necessary for successful self-replication. Beyond carrying out the tasks of routine metabolism, the cell must duplicate its components - most importantly, its genome - so that it can physically split into two complete daughter cells. The cell must also pass through a series of checkpoints that ensure conditions are favorable for division.

Questions about the nature of viruses remain quite vexing. Recent studies of the giant Mimivirus illustrate this point. Its large size and correspondingly large genome test our general ideas of viruses as small, simple entities. The existence of genes associated with translation, metabolism, DNA repair, and protein folding raises questions about the evolutionary history of viruses. Further studies of this virus, and the search for other giant viruses, may shed light on these issues.

The STAR-G Project has put together fact sheets about disorders commonly screened for by newborn screening. The fact sheets were written specifically for families that have received an initial diagnosis of one of the disorders and want to know more general information. They address issues and answer questions that are of particular concern to parents. Each fact sheet was written by a genetic counselor and reviewed by metabolic and genetic specialists.

Nestled in the tissues of your neck is a small, unassuming organ that wields enormous power over your body: the thyroid. Emma Bryce explains how the thyroid, like the operations manager in a company, is tasked with making sure that all the cells in your body are working properly.

Scientists have discovered a new hormone that fights the weight gain caused by a high-fat Western diet and normalizes the metabolism -- effects commonly associated with exercising. When tested in mice, the hormone blocked the negative health effects of eating a high-fat diet.

Unprecedented multiple and extreme-level resistance is generated in mosquitoes found in the rice fields of Tiassalé in southern Côte d'Ivoire. A new study highlights the combination of stringently-replicated whole genome transcription profiling, in vivo transgenic gene expression and in vitro metabolism assays to identify and validate genes from the P450 detoxification enzyme superfamily which are highly expressed in the adult females from the area.