What’s the News: Anxiety. Insomnia. Hallucinations. Methamphetamine’s effects on the human brain are well documented, but researchers know relatively little about how the drug affects the body on the molecular scale. Looking at fruit flies (Drosophila melanogaster), scientists have detailed how meth disrupts chemical reactions associated with generating energy, creating sperm cells, and regulating muscles. Most interestingly, they discovered that meth-exposed fruit flies may live longer when they eat sugar. “We know that methamphetamine influences cellular processes associated with aging, it affects spermatogenesis, and it affects the heart,” says University of Illinois entomologist Barry Pittendrigh. “One could almost call meth a perfect storm toxin because it does so much damage to so many different tissues in the body.”
Posts Tagged ‘drugs’
Sugar Decreases the Havoc That Meth Wreaks on Fruit Flies
Promising Drug to Prevent HIV Fails in Trial–But It’s Not Out of the Picture
UPDATE: The blood tests are in, and it looks like the women instructed to take the pills were not popping them. Only a quarter of those who got infected had any Truvada in their blood. This suggests that the problem isn’t the drug’s effectiveness, but rather compliance on the part of the population.
What’s the News: A much-anticipated trial in African women of an HIV drug found to be effective in preventing infection in men has washed out—researchers announced today that women taking Truvada were no more likely to evade HIV infection than women taking a placebo.
The result is especially disappointing because Truvada, which is an oral pill combining two drugs, emtricitabine and tenofovir disoproxil fumarate, has been shown to be 90% effective in preventing infection in gay men who took it religiously. (more…)
Another Reason Not to Get Sick in Space: the Drugs Don’t Work as Well
What’s the News: In long space flights, such as a mission to Mars, astronauts will have more time during which they could get injured or sick. And the same apparently goes for the medicine aboard spaceships: According to a NASA-funded study, medicines degrade faster in space than they do on Earth. As the researchers conclude in their paper, “this information can facilitate research for the development of space-hardy pharmaceuticals and packaging technologies.”
Viruses Show Promise for Creating Drugs By Doing What They Do Best: Evolving
What’s the News: Test-tube evolution just went viral: a new study shows how to use viruses’ knack for natural selection to create tailored proteins. Researchers at Harvard say their new technique is a hundred times faster than the usual methods, churning through 200 generations of proteins in 8 days, and, crucially, requires no attention from researchers after it’s set up: a crock pot for evolution. Though a godsend primarily for researchers, in the future it could accelerate the growth of customized proteins for new drugs.
Scientists have harnessed the power of viruses in a method for evolving customized proteins.
Promising Cystic Fibrosis Drug Targets the Cause, Not the Symptoms
A study of an experimental drug from the company Vertex, called VX-770, successfully reduced lung problems in CF patients, and the company hopes to try for approval of the drug later this year. If all goes well, doctors may soon have their first drug to treat the cause of this devastating disease, instead of just combatting the symptoms.
Cystic fibrosis is a genetic disease that impairs lung and digestive function. In particular, the normally thin layer of mucus in the lungs thickens up and impairs breathing; this happens because patients have a faulty version of a protein that helps clear mucus.
About 1800 different mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have been implicated in the disease. The gene encodes a molecular channel that shuttles chloride ions across cellular membranes, and people with two mutated copies develop mucus-filled lungs susceptible to infection. Few patients live to see their 30s. In 1989, CF became the first disease pinned to a specific gene mutation, without the benefit of knowing the protein first. [Nature]
This newest test was a Phase III trail of Vertex’s drug, which was funded in part by the Cystic Fibrosis Foundation. The treatment goes after one major genetic mutations that causes the disease, called G551.
Magnetic Medication: How to Steer Pills to Their Targets
When you swallow medication in pill form, it’s hard to control where it goes once it goes into your gut. Unless you equip your pills with tiny magnets, that is.
In the Proceedings of the National Academy of Sciences this week, Edith Mathiowitz and fellow researchers describe an experiment in which they managed to use the power of magnetism to guide gelatin capsules inside the bodies of rats to their intended destination.
The team used a magnet outside the body to direct the movement of the pills in the small intestine, and it used a computer to track the pills to make sure they were responding to the magnet and to ensure that as little force as possible was used, to avoid causing damage). It also took X-rays to visually track the pills’ location in the rats. The researchers found that even after 12 hours, they could control the pill using just 1/60th of the force that would result in damage. [Los Angeles Times]
Bendable New Particles Can Squeeze Through Tiny Blood Vessels
Flexibility matters.
Research teams around the world are attempting to develop new tiny synthetic particles that will enter your bloodstream to act as red blood cells, to play the part of platelets and stop the bleeding, to latch onto damaged areas and deliver drugs there, and more. And to make these lab-created particles as effective as possible, they need to stay in one’s system and not get stuck. In this week’s Proceedings of the National Academy of Sciences, Joseph DiSimone and colleagues say they have figured out a way to mimic the twistable, turnable, bendable, foldable nature of red bloods cells to make long-lasting synthetic particles, and that they’ve tested those particles on a living system, a first.
Previous studies had focused on how size, shape and surface characteristics of particles affected their movement through the bloodstream, the team wrote, but flexibility’s role is less well understood. To test it out, the researchers built artificial cells out of a gel material with “tunable elasticity” — that is, the team could control how deformable the cells were. [Los Angeles Times]
Maximizing that elasticity could allow for particles that can wiggle through tiny blood vessels:
It has long been speculated that the deformability of particles influences how long they circulate and where they are distributed in the body. Red blood cells are equipped for longevity and have an average lifespan of 120 days. As they age, they become stiffer and less capable of passing through the tiny vascular structures in the spleen, where they’re ultimately removed. [Nature]
New Nanoparticles Act Like Burrs to Target & Latch Onto Damaged Cells
We’ve brought you stories of lab-created blood cells able to simulate red blood cells in humans, or to act like platelets in rodents and stop bleeding. Now, in a study soon to be published in the Proceedings of the National Academy of Sciences, comes a new, even smaller creation for our bloodstreams: A nanoparticle that could target and latch onto only the damaged cells in arteries around the heart to deliver drugs there.
The MIT researchers, led by Robert Langer, have developed other nanoparticles to target cancer; this new particle they call a “nanoburr,” named for those seeds covered in bristles or hooks that latch onto animals passing by. Its nanoburrs are coated with proteins which can only stick to a structure in the blood vessel wall called the “basement membrane.” This is only exposed when the wall is damaged, so only damaged sections of blood vessel are targeted [BBC News]. Then the particle can slowly release the drug stored inside.
