Designed by nature: How natural compounds are used in mainstream medicine
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Modern pharmaceuticals have played an important role in extending our lives. When we think about drug discovery, we generally imagine scientists in white lab coats mixing chemicals together until … Eureka, a new magical elixir emerges! However, many of the compounds that form the basis of modern medicines were designed not by man but by nature. In fact, an estimated 67 percent of pharmaceuticals are derived from or inspired by natural products, mainly plants. The importance and legitimacy of natural based medicine is beginning to emerge.
Dr. Francoise Birbira Freedman, an anthropologist at the University of Cambridge, understands the bounty of medicines that nature can provide. She has spent the past 30 years living with and visiting the Quechua Lamas community in Amazonian Peru. During this time she has experienced first hand the power of the medicinal plants growing in this region. One such plant, the Acmella Oleracea or ‘toothache plant’ was given to her when she experienced pain from her wisdom teeth. In 2004, at the request of a neuropharmacologist colleague she brought back medicinal plants including Acmella Oleracea to Cambridge. It performed well in two phases of clinical trials and could move into commercialization by 2014. The toothache plant, however, is just the tip of the iceberg. During her time with the Quechua Lamas community, Freedman collected an impressive phytobase of over 500 plants. This includes information on the taxonomic, agronomic, preparation and medicinal use for each plant. She offers access to this database through partnership with her company Ampika. In setting up Ampika, she also aims to provide a percentage of the proceeds for conservation and education initiatives in Peru.
Another scientist actively engaged in utilizing natural compounds in drug discovery is Dr. Leslie Gunatilaka of the University of Arizona. He has been extracting compounds from Indian Ginseng to determine their effectiveness in curing cancer. He has also designed a system of airoponics to grow medicinal plants. Rather than soaking plant’s roots in nutrient solution, as done in hydroponics, in airoponics the root system of the plants is sprayed with a nutrient solution. Then, researchers go through a number of steps to obtain extracts from the plants, which are tested for therapeutic roles in cancer. In creating this system, Gunatilaka hopes to make cheap and practical pharmaceuticals, which is essential for providing these medicines to poor individuals inflicted by disease.
Herbal extracts practiced in traditional Chinese medicine have become another source of inspiration for pharmaceutical remedies. A team led by Malcolm Whitman at Harvard Medical School investigated the potential of Chang Shan, a hydrangea root extract, in autoimmune diseases. Previously they found the active ingredient, halofuginone (HF), could reduce the autoimmune response without altering overall immunity. HF was able to do this through activation of the amino acid response pathway (AAR), which blocked the development of TH 17 cells implicated in the autoimmune response. Recently, this lab uncovered the mechanism of this effect.
HF acts as a metabolic sensor through binding with glutamyl-prolyl-tRNA synthetase (EPRS), which inhibits prolyl-tRNA synthetase. This blockage results in the turning on of the AAR pathway. Furthermore, they determined that the activation of the AAR pathway, rather than the blockage of protein synthesis, results in the therapeutic effects. These findings implicate metabolic signaling and the AAR pathway in the autoimmune response providing the basis for future studies to investigate this pathway as a target for drugs in treating autoimmune diseases.
Natural remedies have also been put forward for acne, can greatly affect a person’s self esteem (just ask a teenager). Current treatments for acne utilize benzoyl peroxide, which can cause burning sensation and skin irritation. Researchers at Leeds Metropolitan utilized a basic disinfectant test to determine the efficacy of natural tinctures, mixtures made from soaking a plant in alcohol for weeks or longer, and benzoyl peroxide at killing propionibacterium, the bacteria responsible for causing acne. They found that a tincture of thyme killed the propionibacterium better than benzoyl peroxide. The next step is to test this on skin like materiel to see its effectiveness.
Above are just a few examples of recent findings in potential pharmaceuticals derived from plants (for a snapshot of some other natural based drugs see this gallery). Clearly, nature has a lot of insight into curing things that ail us. This does not mean that lab-coated scientists do nothing at all. Scientific discovery tests and determines the safety and efficacy of these compounds. Research also delves into the active ingredients and determine ways to synthesize these compounds to make them more effective and available in a large scale. While it is important to give science its due applause in the discovery of medicinal agents, it is also important to acknowledge the inspiration that nature provides in designing these drugs as well. This acknowledgement is essential, as numerous medicinal plants face threat of extinction. While we may be able to synthesize many of the compounds originally derived from natural plants, we are unable to synthesize medicinal compounds from plants yet to be discovered. This means conservation efforts and safety nets for these plants are essential to allow us to continue to utilize nature to inspire life saving medicines.