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How Bioprospecting The Past Could Help Us Develop New Medicines

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Contemporary Bioprospecting: a new focus

The concept of bioprospecting the planet’s natural environment to discover new sources of drugs and treatments to combat disease is a well-established practice in modern medical science. However, the successful reappraisal and deployment of the ‘wisdom of the ancients’, such as the recent discovery that an Anglo-Saxon remedy is just as effective against MRSA as a modern-day treatment, suggests an entirely new direction for creative bio-prospectors.

Early Chinese and Arabic medical texts have already proved a promising source of long-forgotten remedies, and many researchers believe that an historical examination of ancient cultures, plus an open-minded review of time-honoured folk medicines, has similar potential to save modern scientists much time and expense reinventing the wheel.

Medieval microbiologyBalds Leechbook

A speculative collaboration between an Anglo-Saxon scholar, Christina Lee, and a Nottingham University microbiologist, Freya Harrison, took a fresh look at ‘Bald’s Leechbook’. This one-thousand-year-old Anglo-Saxon medical text retained in the British Library includes instructions for brewing a potion to cure an infected eyelash follicle. For Lee and Harrison, carefully following this Old-English recipe to heal an irritating and unsightly stye first involved assembling an exotic miscellany of ingredients: wine, bullock’s gall, cropleek and garlic. Once pounded together and mixed, the resulting slimy composite was then to ‘stand nine days in a brass vessel’.

Close adherence to the prescribed detail was often problematic. An ancient English vineyard of proven heritage supplied a suitable organic wine, but the recipe had to make do with modern strains of garlic and leeks. Likewise, glass bottles containing quantities of brass clipped from a larger sheet served as a low-cost alternative to a brass vessel, with the added advantage that these were also easier to sterilise. Thankfully, cow-bile salts are a modern treatment, being supplied to anyone whose gall bladder has been removed, thus proving a convenient substitute for the bullock’s gall ingredient.

A potent elixir

Brewed for nine days, the potion looked revolting but its smell was more appealing. More importantly, as Harrison observed, the concoction had clearly eradicated all traces of soil bacteria harboured by the garlic and leek ingredients. “It was self-sterilising,” she said. “That was the first inkling that this crazy idea just might have some use.”

Subsequently, this Anglo-Saxon stye preparation was put to the test against a sample of Staphylococcus aureus. This bacterial strain causes styes, is known to be resistant to methicillin, and frequently appears elsewhere in MRSA, the feared hospital superbug. Trial results demonstrated that the medieval mixture was 90 percent effective against the bacteria, matching the performance of Vancomycin, the modern antibiotic equivalent developed for use against MRSA.

Following earlier failures, researchers have learned that careful, nuanced preparation of the ingredients holds the key to activating the potency of the resultant elixir, and believe the discovery has important implications for the future treatment of antibiotic-resistant skin infections.

The return of the leechLeech

Far from being a forgotten cure, leeches were known and widely used for medicinal bloodletting in many cultures across the ancient world. However, they disappeared from Western medical practice not long after the dawn of the nineteenth century. As a result, the word ‘leech’, which had once been a popular nickname for a doctor, began to acquire more pejorative overtones.

Partly responsible for the abandonment of leeching, French doctor Pierre-Charles-Alexandre Louis championed the use of statistical analysis to judge the efficacy of a range of medical treatments. His evidence found bleeding to be a generally ineffective means of treating many conditions. In addition, he also suggested that ‘the lancet’ had proved a more useful tool for the procedure than the leech.

Soon all leeching stopped and medical opinion declared that bloodletting did little more than weaken patients. This view condemned leeching as a barbaric and antiquated practice, an assumption which held sway for the next 150 years. It was not until the late twentieth century that medical science re-evaluated the use of leeches, discovering that, in certain strictly defined medical circumstances, this favoured tool of ancient physicians could be very effective indeed.

Acquiring immunityMary Wortley

The standard medical practice of vaccination also first came to the attention of medical science due to the influence of ‘folk cures’. First known as ‘variolation’, this treatment was brought to the UK from Turkey by Lady Mary Wortley Montagu during the early eighteenth century. The wife of Lord Montagu, who was then Britain’s Ambassador to Turkey, Lady Montagu had observed the artificial infection of Turkish children with smallpox. The resultant mild sickness, she noted, usually protected those treated from any future recurrence of the malignant disease. Similar forms of artificial infection against smallpox had been known in Asia and the Middle East for centuries, including the use of a snuff preparation consisting of dried and ground smallpox scab tissue.

The practice of variolation simultaneously spread to the North American colonies where it was equally effective. However, 2012 research examining traditional Native American herbal remedies found an alternative smallpox cure, providing a second line of defence against the future re-emergence of smallpox.

Towards the close of the eighteenth century, Edward Jenner developed a much safer method of acquiring immunity against smallpox. Instead of an artificial dose of smallpox, the process introduced a milder cowpox infection instead. Jenner’s innovation was prompted by the prevailing folk wisdom of the day which observed that those who experienced an early cowpox infection rarely caught the more-dangerous smallpox afterwards.

Research strategies

Evidently, replicating forgotten cures is a remarkably efficient means of advancing medical science. Given the prior existence of folk knowledge and historical texts offering clues, concepts, and factual information worthy of further exploration, can we afford to ignore such a resource?

A parallel concern is the need to also preserve and develop the necessary skills to access and analyse such wisdom. Paleographers will be required to decipher ancient writings, whilst Anglo-Saxon scholars and academics in many other cultural disciplines would be needed to assemble and configure the evidence available.

There are, of course, costs attached to such proposals. However, if we are serious about bioprospecting, should we not seek to protect linguistic expertise in obsolete languages, in the same way that we campaign to preserve our rainforests?[/fusion_text][/one_full][/fullwidth]