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Drugs could turn couch potatoes into athletes
Cannabis chemical For some people, there’s no such thing as a silent movie clue to colon cancer
JAMES EMMETT/EYEVINE
www.newscientist.com
WHAT is the sound of dots moving? Most can’t say, but for those with a newly identified form of synaesthesia, “hearing” sights is the most natural thing in the world – and may make it easier for synaesthetes to recognise visual patterns. Melissa Saenz at the California Institute of Technology in Pasadena was tipped off when a grad student saw her screensaver and asked: “Does anyone else hear that?” His experience had the hallmarks of synaesthesia, in which stimulation of one sensory
pathway creates an experience in another. When Saenz circulated the “noisy” image via email, three more synaesthetes came forward. Ordinarily, people are better at recognising patterns if they are auditory rather than visual. To see if hearing-sight synaesthesia might make people better at recognising visual patterns, Saenz and collaborator Christof Koch asked the synaesthetes and a group of controls to listen to or watch pairs of sequences in the same modality and say whether they were identical; half were and
half weren’t. Both groups were about 85 per cent accurate on the sound patterns, but while controls got only 55 per cent of the visual rhythms right, synaesthetes remained steady at 85 – and they reported later that they were indeed hearing the flashes as well as seeing them (Current Biology, DOI: 10.1016/j.cub.2008.06.014). “You can’t fake being better,” says neuroscientist Jamie Ward at the University of Sussex, UK. Finding new types of synaesthesia is not uncommon, he says, and they often confer an advantage.
Run all day long after popping a pill
training with doses of a compound, WG1516. This activates a gene that causes cells to burn extra fat and make more mitochondria – the cell’s power-producing structures. When tested on endurance, those that had taken the compound jogged longer and further than the mice that did not (Cell, DOI: 10.1016/j.cell.2008.06.051). Their muscles also boasted more “slow-twitch” fibres, which are important for endurance. In a second experiment, mice with no prior treadmill training were injected with a different compound, AICAR. This encourages the production of muscle fuel, and enabled mice to run about 44 per cent longer than untreated mice. “This is the couch potato experiment,” says Evans.
ANDY CLARK/ACTION IMAGES
SMOKING hash or marijuana may not be the healthiest way to do it, but taking substances similar to those found in cannabis might one day help to treat colon cancer. Raymond DuBois and colleagues at the University of Texas, Houston, discovered that a key receptor for cannabinoids – compounds similar to the active ingredient of cannabis – is turned off in most types of human colon cancer cells. Similarly, mice genetically engineered to develop colon tumours developed more of them if the receptor, called CB1, was knocked out (Cancer Research, DOI: 10.1158/0008-5472.CAN-08-0896). What’s more, tumours shrank when the genetically engineered mice were injected with a cannabinoid. One suggestion is that lack of CB1 encourages tumour growth because the receptor normally interacts with cannabinoids made by the body to prompt cells to die. This opens up a possible two-step treatment for colon cancer. First, switch CB1 back on using decitibine, a drug already approved for use in humans which DuBois and his team showed stops blockage of the receptor in human colon cancer cells. Then give the patient cannabinoids to activate CB1. The research also casts a shadow on the weight-loss drug rimonabant. The drug suppresses appetite by blocking CB1, which is involved in hunger as well as tumour growth. DuBois suggests that anyone on the drug be screened for colon cancer.
Megastars made an early showing GIANT stars did indeed illuminate the early universe. Astronomers have wondered whether the first coalescing gas clouds would have been unstable and fragmented to create only small primordial stars. Now the most complete simulation yet of star formation after the big bang suggests this did not happen. In the model, created by a team led by Naoki Yoshida of Nagoya University in Japan, huge stars coalesce about 300 million years after the big bang. At first, patches of hydrogen and helium gas collapse under gravity and slowly warm up. Hydrogen atoms then form molecules, which radiate away the building heat, reducing thermal pressure and allowing the cloud to collapse further to form a protostar. “The first object to be formed in the universe is a very tiny protostar with mass just 1 per cent of the sun,” says Yoshida. That star then acts as a seed, quickly growing to about 100 times the mass of the sun. After a brilliant million-year lifetime, such a star might explode as a supernova, scattering heavy elements and triggering more star formation.
TOO busy to go for a run? One day you might be able to build endurance just by popping a pill. Ronald Evans of the Salk Institute in La Jolla, California, has discovered two compounds that turn ordinary mice into long-distance runners, and that one of them works even if the mice don’t exercise beforehand. If they have the same effect in people, the compounds may one day be used to fight obesity, by increasing fat metabolism. Evans fears, though, that they could be abused by athletes. His team trained mice on a treadmill and for half of them paired
9 August 2008 | NewScientist | 17
JAMES EMMETT/EYEVINE
www.newscientist.com
WHAT is the sound of dots moving? Most can’t say, but for those with a newly identified form of synaesthesia, “hearing” sights is the most natural thing in the world – and may make it easier for synaesthetes to recognise visual patterns. Melissa Saenz at the California Institute of Technology in Pasadena was tipped off when a grad student saw her screensaver and asked: “Does anyone else hear that?” His experience had the hallmarks of synaesthesia, in which stimulation of one sensory
pathway creates an experience in another. When Saenz circulated the “noisy” image via email, three more synaesthetes came forward. Ordinarily, people are better at recognising patterns if they are auditory rather than visual. To see if hearing-sight synaesthesia might make people better at recognising visual patterns, Saenz and collaborator Christof Koch asked the synaesthetes and a group of controls to listen to or watch pairs of sequences in the same modality and say whether they were identical; half were and
half weren’t. Both groups were about 85 per cent accurate on the sound patterns, but while controls got only 55 per cent of the visual rhythms right, synaesthetes remained steady at 85 – and they reported later that they were indeed hearing the flashes as well as seeing them (Current Biology, DOI: 10.1016/j.cub.2008.06.014). “You can’t fake being better,” says neuroscientist Jamie Ward at the University of Sussex, UK. Finding new types of synaesthesia is not uncommon, he says, and they often confer an advantage.
Run all day long after popping a pill
training with doses of a compound, WG1516. This activates a gene that causes cells to burn extra fat and make more mitochondria – the cell’s power-producing structures. When tested on endurance, those that had taken the compound jogged longer and further than the mice that did not (Cell, DOI: 10.1016/j.cell.2008.06.051). Their muscles also boasted more “slow-twitch” fibres, which are important for endurance. In a second experiment, mice with no prior treadmill training were injected with a different compound, AICAR. This encourages the production of muscle fuel, and enabled mice to run about 44 per cent longer than untreated mice. “This is the couch potato experiment,” says Evans.
ANDY CLARK/ACTION IMAGES
SMOKING hash or marijuana may not be the healthiest way to do it, but taking substances similar to those found in cannabis might one day help to treat colon cancer. Raymond DuBois and colleagues at the University of Texas, Houston, discovered that a key receptor for cannabinoids – compounds similar to the active ingredient of cannabis – is turned off in most types of human colon cancer cells. Similarly, mice genetically engineered to develop colon tumours developed more of them if the receptor, called CB1, was knocked out (Cancer Research, DOI: 10.1158/0008-5472.CAN-08-0896). What’s more, tumours shrank when the genetically engineered mice were injected with a cannabinoid. One suggestion is that lack of CB1 encourages tumour growth because the receptor normally interacts with cannabinoids made by the body to prompt cells to die. This opens up a possible two-step treatment for colon cancer. First, switch CB1 back on using decitibine, a drug already approved for use in humans which DuBois and his team showed stops blockage of the receptor in human colon cancer cells. Then give the patient cannabinoids to activate CB1. The research also casts a shadow on the weight-loss drug rimonabant. The drug suppresses appetite by blocking CB1, which is involved in hunger as well as tumour growth. DuBois suggests that anyone on the drug be screened for colon cancer.
Megastars made an early showing GIANT stars did indeed illuminate the early universe. Astronomers have wondered whether the first coalescing gas clouds would have been unstable and fragmented to create only small primordial stars. Now the most complete simulation yet of star formation after the big bang suggests this did not happen. In the model, created by a team led by Naoki Yoshida of Nagoya University in Japan, huge stars coalesce about 300 million years after the big bang. At first, patches of hydrogen and helium gas collapse under gravity and slowly warm up. Hydrogen atoms then form molecules, which radiate away the building heat, reducing thermal pressure and allowing the cloud to collapse further to form a protostar. “The first object to be formed in the universe is a very tiny protostar with mass just 1 per cent of the sun,” says Yoshida. That star then acts as a seed, quickly growing to about 100 times the mass of the sun. After a brilliant million-year lifetime, such a star might explode as a supernova, scattering heavy elements and triggering more star formation.
TOO busy to go for a run? One day you might be able to build endurance just by popping a pill. Ronald Evans of the Salk Institute in La Jolla, California, has discovered two compounds that turn ordinary mice into long-distance runners, and that one of them works even if the mice don’t exercise beforehand. If they have the same effect in people, the compounds may one day be used to fight obesity, by increasing fat metabolism. Evans fears, though, that they could be abused by athletes. His team trained mice on a treadmill and for half of them paired
9 August 2008 | NewScientist | 17