Vampire Bat Saliva nad Other Strange Cures Oct 31, 2013 16:16:36 GMT -5
Post by natalie on Oct 31, 2013 16:16:36 GMT -5
By Lisa Collier Cool, Oct 30, 2013
A witches’ brew of spooky substances – from saliva of vampire bats and Gila monsters to centipede venom and even snake oil – could be tomorrow’s cures for dangerous diseases, as scientists turn to “extreme biology” in their quest for potentially lifesaving discoveries.
In one of the most intriguing studies, stroke patients at about 60 US medical centers are being offered an experimental clot-busting drug that has been nicknamed “Draculin” because it’s derived from enzymes found in the saliva of the common vampire bat (Desmodus rotundus). These enzymes are a natural blood-thinner that the fanged predators inject into the mammals they bite in order to get a larger blood meal. The drug contains a purified form of the enzymes to dissolve the blood clots that cause ischemic stroke (the most common form of stroke).
‘Draculin’ Showing Great Promise in Saving Stroke Patients. The new drug, desmoteplase, is showing “great promise” in two ongoing phrase 3 clinical trials called DIAS-3 and DIAS-4, reports Philip B. Gorelick, MD, neurologist and medical director, Saint Mary’s Mercy Hospital’s Hauenstein Neuroscience Center and the Co-director of the US DIAS Study Clinical Coordinating Center.
Currently, there is only one FDA-approved clot-busting drug for ischemic stroke: tPA (tissue plasma activator), which must be given within 3 hours of onset of stroke symptoms. But very few stroke victims get to the hospital fast enough to qualify, says Dr. Gorelick. That’s because stroke is typically not painful and patients may not recognize the symptoms – which include dizziness, sudden numbness or weakness in the face, arm or leg (especially on one side of the body), confusion, and blurry vision – as a life-threatening medical emergency. Every year, more than 795,000 Americans suffer a stroke and nearly 130,000 die, according to the CDC.
Desmoteplase could extend the lifesaving treatment window up to nine hours and has shown an excellent safety profile in the clinical trials, US and German researchers reported earlier this year. The randomized, double-blind trials will ultimately include 880 patients. “Desmoteplase seems to have less toxicity and lower risk for brain bleeding than tPA – and has a higher fibrinogen specificity, meaning that it gloms on to clots more effectively,” reports Dr. Gorelick. “Because the drug has a longer half life than tPA, it also gives patients a better chance to avoid having the clot recur.” If Draculin ultimately wins FDA-approval, it would be the first new stroke drug in nearly 20 years.
Is ‘Snake Oil’ a Potential Cure for Heart Disease? Best known for swallowing alligators and other large prey whole, pythons turn out to have very big hearts that may hold the secret to treating human cardiovascular disorders, including heart failure. Leslie Leinwand, chief scientific officer of BioFrontiers Institute, has embraced “extreme biology,” in potentially groundbreaking research on “snake oil,” found in Burmese pythons’ blood after a meal. The huge snakes can survive with as little as one meal a year.
After chowing down, the snakes’ triglyceride levels rise as much as 50-fold and their hearts balloon in size – in a beneficial way. Furthermore, Leinwand and colleagues identified 3 fatty acids in python blood, which they call “snake oil,” that also increase the size of the hearts of fasting pythons and healthy mice. The researchers reported this in a 2011 paper in Science. Since then, she says, “we did more testing and found that the changes in mouse hearts treated with these fatty acids are similar to what occurs due to regular, vigorous exercise.”
According to Leinwand, “Athletes like Michael Phelps have large, strong hearts and exercise is one of the best ways to improve heart health or even reverse disease in some cases. But people with some cardiac conditions, such as heart failure, aren’t able to exercise enough to achieve this type of beneficial change.” Instead, heart failure patients typically have large, but weak hearts that don’t pump blood very well. Leinwand and team are now seeking funding for studies to find out if snake oil is helpful for animals with heart disease. If so, it might ultimately lead to new treatments for people.
Worms, Gila Monsters and Other Weird Medical Treatments. Investigations into “extreme biology” become more common, creepy crawlies are finding their way into more medical research and treatments:
Using Gila monster spit to treat diabetes and obesity. The FDA-approved diabetes drug, Byetta (exenatide), contains a synthetic form of a hormone found in the saliva of venomous lizards called Gila monsters. In a three-year study of type 2 diabetics, treatment with the drug lead to both weight loss and sustained improvement in blood sugar levels. The lizard hormone is similar to one naturally found in the human digestive tract that boosts insulin production when blood glucose rises. A 2012 animal study also found that the lizard-spit drug may help curb chocolate and food cravings, potentially offering new hope for those with obesity or eating disorders.
Centipede venom to combat pain. A peptide found in Chinese red-headed centipede venom could be a remarkably powerful painkiller, researchers report. Indeed, in an animal study, the venom proved more potent than morphine and even at high doses, didn’t cause any side effects. The peptide acts on a protein that transmits pain signals up the spinal cord to the brain, according to new research published in Proceedings of the National Academy of Sciences.
Worms to battle bowel and autoimmune disorders. Intestinal parasites could be a new weapon against autoimmune diseases including type 1 diabetes, rheumatoid arthritis, lupus, and Crohn’s disease (a painful bowel disorder). Some scientists, including immunologist Dr. William Guase of Rutgers New Jersey Medical School, theorize that a lack of parasites in our overly clean modern world may explain why rates of intestinal and autoimmune disorders are skyrocketing. Dr. Gause theorizes in the past, when worm infection was common, people developed a protective response called type 2 immunity to improve healing from intestinal injuries caused by the tiny parasites. In his study, people with compromised immune systems will be treated with live worms (on a short-term basis). A small British study is investigating worm therapy for multiple sclerosis, BBC News reports.
Maggots and leeches to improve wound healing. An ancient treatment is new again. With growing numbers of patient suffering from chronic wound infections that are resistant to antibiotics, doctors are turning to leeches and even medicinal maggots, which eat bacteria and secrete enzymes that dissolve dead tissue, while leaving healthy tissue intact. “Studies indicate that about 40% to 50% of wounds treated with maggot therapy as the last alternative before amputation were healed, and the limbs were saved," Dr. Ronald Sherman, a pathologist at UC Irvine, told Medscape. What’s more, maggots have actually received FDA clearance as “medical devices.” Both leech and maggot treatments for certain wounds are even covered by some insurance plans.