Biotechnology for Medicine (continued-3)
Natural habitat conditions sometimes demonstrate almost unique capabilities of animals to neutralize toxins or infections. An almost inexhaustible source of potential medicines is the ocean. Biotechnologists working with marine flora and fauna have discovered organisms synthesizing substances that can be used as a means of symptomatic and pathogenetic therapy in the treatment of various diseases.
So, Australian scientists from the University of Queensland conducted experiments with the venom of a mollusk living in the Great Barrier Reef, Conus marmoreus (marble cone). The poison that the snail injects into the victim in order to paralyze her may turn out to be a medicine in a certain proportion. This toxin does not give side effects, is very effective in blocking pain and, according to scientists, can replace morphine. Obtaining it, however, from 6-centimeter mollusks is very expensive, so work has been carried out on its chemical synthesis, and now they have successfully completed the production of a synthetic analogue. This will make it possible to obtain the specified toxin in quantities necessary for clinical use.
New drugs for pain relief based on conotoxins are being developed by the staff of the Medical Faculty of Harvard University (Boston, USA). Conotoxins contained in the tissues of some tropical mollusks are used by them to protect against enemies, depriving the attacker of sensitivity and paralyzing him. According to scientists, new drugs should be more effective and safer than most modern painkillers.
Studies conducted at the University of Massachusetts on the bivalve mollusk Mercaria mercaria have found that this bivalve effectively neutralizes botulism toxin in a concentration capable of killing 1 thousand people.
Indian experts from New Delhi have isolated the antioxidant lycopene from some marine mollusks, which is used to treat and prevent oral cancer, as well as some types of male infertility.
According to Oxford University researchers, purified chitin preparations from the shells of ordinary shrimp can be used as an anti-allergic agent, which is an order of magnitude safer than modern anti-allergic agents. In addition, chitin from shrimp and crabs can be used to transport drugs through the body.
Scientists are particularly interested in frog poisons, which have various effects: lower blood pressure, dilate blood vessels, stimulate respiration and blood circulation, have a detrimental effect on helminths, promote wound healing, protecting them from suppuration. In particular, an effective medicine for fighting skin fungi has been synthesized on the basis of the components of frog venom. The synthesis of analogues of these complex compounds will ensure the mass production of drugs that can replace antibiotics. In addition, poisonous tree frogs also provide us with painkillers.
An equally interesting observation was made by British scientists regarding the crested crocodile Crocodylus porosus, which lives in swamps in northern Australia. Even the most severe wounds of these reptiles never become inflamed, despite the abundance of pathogenic bacteria in the swamps. Zoologist A. Britton found an exceptionally effective antibiotic in the animal's blood, called "crocolillin".
We should also not forget that anticoagulants, widely used in vascular surgery, are also of animal origin. In nature, their source is ticks and leeches.
Currently, about 50% of all widely used medicines in the world are based on plants and microbes. At the same time, the share of medicines of animal origin is much more modest, and there are practically no medicines obtained from insects. However, the insect world is truly limitless: about two million species are known to science. These amazing creatures over their nearly 500 million-year history have created one of the most complex immune systems capable of fighting viruses, bacteria and other pathogens.
Research in this area, we can say, is just beginning. Thus, a drug with fungicidal properties was isolated from the larvae of South American butterflies.
Wax moth served as a raw material for medicines against tuberculosis and cardiovascular diseases. Research by scientists of the Institute of Theoretical and Experimental Biophysics of the Russian Academy of Sciences has established that this drug stimulates the immune system and physical activity, regulates energy metabolism, and has high antioxidant activity.
Of particular interest are calliphora flies, which in their natural habitat, entering into competitive relations with bacteria, secrete substances that inhibit their growth. When the larvae get into the wounds, they heal quickly. This property was actively used in the field by the Russian surgeon Pirogov during the First World War, and now the scientific center in Nottingham (UK) is specifically engaged in the cultivation of these larvae, which are used in some clinics in the USA and Switzerland in the treatment of patients with trophic ulcers and osteomyelitis.
The most significant and interesting studies of the immune system of insects belong to the staff of St. Petersburg State University. As a result of many years of work, it was possible to analyze and isolate, and then create synthetic analogues of molecules with anti-infective activity. As a result, a new antiviral drug, alloferon, has appeared, which is used to treat herpes and hepatitis B. Currently, on the basis of peptides of the insect immune system, a new generation of drugs with antiviral activity, called entovirons, is being developed, as well as allostatin drugs that have both antiviral and anticancer effects.