Free Republic

Rutgers and collaborating institutions have found that overnutrition leads to insulin resistance and metabolic disorders through increased activity of the sympathetic nervous system (SNS). The study shows that reducing SNS activity can prevent insulin resistance induced by a high-fat diet, suggesting a new understanding of how obesity causes insulin resistance. Obesity causes type 2 diabetes and metabolic diseases primarily by inducing insulin resistance. Impaired cellular insulin signaling is the most understood mechanism, but it does not always accompany impaired insulin action, indicating other factors must be involved. Overnutrition has been known to rapidly increase plasma norepinephrine (NE) levels, indicating overactivation...

Boosting the level of a brain chemical reverses learning impairments in a mouse model of Down syndrome, researchers report. The work adds to emerging evidence that cognition-enhancing drugs may one day help humans with Down syndrome lead more independent lives. Down syndrome is the most common cause of mental retardation, affecting approximately one in 800 babies at birth. People with the disorder have an extra copy of chromosome 21, giving them additional copies of hundreds of genes. This somehow alters brain development and causes mild to severe learning disabilities. To investigate what goes wrong in the brain of someone who...

Now, findings from the Stanford University School of Medicine and Lucile Packard Children's Hospital shed light on the neural basis of memory defects in Down syndrome and suggest a new strategy for treating the defects with medication. The study, which was conducted in mice, is the first to show that boosting norepinephrine signaling in the brains of mice genetically engineered to mimic Down syndrome improves their cognition. Norepinephrine is a neurotransmitter that nerve cells use to communicate...

Enhancing specific chemical signaling in the brain could help treat the disorder. By Emily Singer Drugs that boost the chemical messenger norepinephrine in the brain have been shown to alleviate cognitive problems in mice engineered to mirror Down syndrome. The findings, published today in the journal Science Translational Medicine, suggest a new approach to treating the disorder. Several existing drugs can boost the chemical or mimic its effects, though none have yet been tested in patients with Down syndrome. The research also reflects a growing understanding of the brain systems that underlie the cognitive problems in people with Down syndrome,...

Laurie Coots, a marketing executive who flies to meetings in other countries twice a week, spent years trying to conquer sleepless nights and chronic jet lag. But nothing worked, she says, and every day was a struggle to stay awake. "It was debilitating," said Ms. Coots, 46, who is from Los Angeles. "I couldn't give an effective presentation because I was always shaky and nervous from being amped up on caffeine and stimulants." Then she found modafinil, a small white pill that revs up the central nervous system without the jitteriness of caffeine or the addiction and euphoria of amphetamines....