Genetics & Molecular Biology

Most people know that our biological functions use a circadian system comprised of a central clock located deep within the center of our brains and multiple clocks located in different parts of the body.    When people fly to the other part of the world or work a night shift, those different biological clocks have not adjusted and so we get things like 'jet lag'. A small study may open new therapeutic avenues for improving the synchronization of the body's different biological clocks.   Writing in The FASEB Journal, Marc Cuesta, Nicolas Cermakian and Diane B. Boivin from the…

A molecule known as coenzyme A plays a key role in cell metabolism by regulating the actions of nitric oxide. according to a new study. Cell metabolism is the ongoing process of chemical transformations within the body's cells that sustains life, and alterations in metabolism are a common cause of human disease, including cancer and heart disease. Their findings about the mechanisms of action for coenzyme A, as well as discovering a new class of enzymes that regulate coenzyme A-based reactions.  Coenzyme A sets into motion a process known as protein nitrosylation, which unleashes nitric…

In a laboratory first, researchers have grown human skeletal muscle that contracts and responds just like native tissue to external stimuli such as electrical pulses, biochemical signals and pharmaceuticals. The lab-grown tissue should soon allow researchers to test new drugs and study diseases in functioning human muscle outside of the human body. The researchers started with a small sample of human cells that had already progressed beyond stem cells but hadn't yet become muscle tissue. They expanded these "myogenic precursors" by more than a 1000-fold, and then put them into a supportive, 3…

In a new study, an analysis of 5,749 patients who received dalcetrapib or placebo and provided DNA in a clinical study found a strong association between the effects of dalcetrapib and a specific gene called ADCY9 (adenylate cyclase 9) on chromosome 16, particularly for a specific genetic variant (rs1967309). In patients with the genetic profile AA at rs1967309, there was a 39% reduction in the composite cardiovascular endpoint with dalcetrapib compared to placebo. Supporting evidence was also obtained from a second study, which showed that patients with the favorable genetic profile also…

Sensory 'hair cell' loss is the major cause of hearing loss and balance disorders. The postnatal mammalian inner ear harbors progenitor cells which have the potential for hair cell regeneration - and hearing recovery - but the mechanisms that control their proliferation and hair cell regeneration are yet to be determined.  A new study has shown that blocking the Notch pathway, known to control the elaborate hair cell distribution in the inner ear, plays an essential role that determines cochlear progenitor cell proliferation capacity.  "A high level of Notch activity prevents…

A study of circadian rhythms in skin stem cells finds that this biological clock plays a key role in coordinating daily metabolic cycles and cell division. The paper shows how the body's intrinsic day-night cycles protect and nurture stem cell differentiation and provides insights into a mechanism whereby an out-of-synch circadian clock can contribute to accelerated skin aging and cancers. Bogi Andersen, professor of biological chemistry and medicine at University of California - Irvine, and Enrico Gratton, professor of biomedical engineering, focused their efforts on the epidermis, the…

White fat and brown fat have been well documented regarding metabolism but new research has introduced data that may be important this winter and this new year: each type of fat may change into the other, depending on the temperature. In particular, cold temperatures may encourage "unhealthy" white fat to change into "healthy" brown fat. So if you needed a good reason to turn down the thermostat, you can now show it is part of your diet. To make the discovery, researchers used techniques that allowed them to tag specific cell populations (undifferentiated progenitors or differentiated…

Humans who eat a lot of red meat are known to be at higher risk for certain cancers but other carnivores are not, which is a bit of an epidemiological puzzle, mostly because cancer rates in animals are not well-known. In a recent study,  University of California, San Diego School of Medicine scientists wanted to  investigate the possible tumor-forming role of a sugar called Neu5Gc, which is naturally found in most mammals but not in humans, and found that feeding Neu5Gc to mice engineered to be deficient in the sugar (like humans) significantly promoted spontaneous cancers. The…

It's commonly said that moderate alcohol consumption is good for people, but no one knew why and the determination of moderate was arbitrary. A new study of 618 Swedes with coronary heart disease and a control group of 3,000 healthy subjects lent evidence to epidemiological curve-matching. The subjects were assigned to various categories based on the amount of alcohol they consumed and were tested in order to identify a particular genotype (CETP TaqIB) that previous studies suggested played a role in the health benefits of alcohol consumption. The results showed that moderate consumption of…

Multiple sclerosis is a degenerative disease and most patients with RRMS who received disease-modifying therapies experience breakthrough disease. Autologous (using a patient's own cells) hematopoietic cell transplant (HCT) has been studied in multiple sclerosis with the goal of removing disease-causing immune cells and resetting the immune system.  Three years after a small number of patients with multiple sclerosis (MS) were treated with high-dose immunosuppressive therapy (HDIT) and then transplanted with their own hematopoietic stem cells, most of the patients sustained remission of…