Wednesday 28 Dec, 2016

Nobel Journeys: Tu Youyou

The following is an excerpt from Nobel Journeys, a story collection that chronicles the extraordinary lives of Nobel Prize Laureates from the past and present, from all over the world, and from every Nobel Prize category. All 10 stories focus on important moments of discovery in the Laureates’ lives that helped them choose their unique pathways to success. And every tale reinforces the notion that education is an essential ingredient to a bright future.

Nobel Journeys is the first of many joint initiatives from the Nobel Museum and EF Education First, two global organizations dedicated to bringing learning to life for students. Download a free copy of the full book and accompanying lesson plan for your classroom, and show your students that great ideas can come from anyone, at any time.

In 2015, Tu Youyou was awarded the Nobel Prize in Physiology or Medicine for the development of an antimalarial drug called Artemisinin. Since its discovery in the 1970s, Artemisinin has saved millions of lives. Malaria death rates have decreased 47% worldwide and infection rates among children have dropped 46%. Tu insists that Artemisinin is more of a re-discovery. The drug is extracted from a Chinese herb called quinghao, or sweet wormwood, which has been used in traditional Chinese medicine for 2,000 years. As a young pharmacologist in Beijing, Tu was made head of a top-secret military program called Project 523, established by Mao Zedong, to research future cures for malaria. Her road to discovery was not an easy one. It would take her deep into China’s cultural past. As it turns out, a line from an ancient medical text dating back to the Han Dynasty would provide her with a vital clue to the answer.

Youyou’s entire life changed in 1969. She was 39 years old and, until then, she had worked as a pharmacology teacher and research scientist at Beijing’s Academy of Traditional Chinese Medicine – a unique institute of historians, chemists, scientists, and doctors dedicated to bringing traditional Chinese practices up to scientific standards. Youyou was now astonished to learn she would head a newly formed research group of chemists and pharmacologists at the institute for a top-secret military program called Project 523.

tu-youyou

Established by Chairman Mao himself, Project 523’s main goal was to find ways of preventing and curing malaria. For two years, the project had focused on developing western-style antimalarial drugs. Hundreds of scientists had already tested thousands of synthetic compounds – to no avail. Project 523 was now turning to traditional Chinese medicine and herbal remedies for answers.

This came as a surprise. One of the main objectives of Mao’s Cultural Revolution was to preserve communist ideology by purging China of traditional literature and art. Intellectuals and scholars were now considered to be the lowest caste of Chinese society. Scientific research was only sanctioned if its purpose was practical. Clearly, Chairman Mao believed traditional Chinese medicine – and Tu Youyou – could solve a practical problem.

Youyou had been specifically chosen, she was informed, because of her unique combination of skills. She had a degree in western pharmacology, yet she had also trained for two years with a noted professor of Chinese medicine and knew how to differentiate among thousands of herbs. She and her team should prepare to leave at once for Hainan, a tropical island in the far south of China, to study people afflicted with the disease.

Youyou felt deeply honored. She was young, and she was a woman. But she was a little overwhelmed. She knew the road ahead would be difficult. Strains of malaria were resistant to every available drug. And scientists worldwide had already screened over 240,000 compounds without a shred of success. Plus she was – at the moment – a single parent. Her husband Li Tingzhao had recently been “sent down to the countryside” on a mandatory exchange program for “re-education.” She had no other choice but to place her three-year-old daughter in a local nursery while she was away.
Little did Youyou realize this would be for six months.

She missed her daughter very much in Hainan. And she found it especially difficult to examine young children dying of malaria. But she gained a newfound respect for the traditional Chinese medicine practitioners her team encountered in every village; they provided an admirable amount of comfort to their patients – if not an actual cure. Since most of their skills had been handed down orally, Youyou and her team recorded the remedies and treatments they learned in notebooks. They also combed the library for every medical text they could lay their hands on. In the end, they collected over 2,000 recipes for herbal, animal, and mineral prescriptions. From these, they chose 640 with the best hope of a potential cure, summarizing them in a notebook Youyou called Collection of Single Practical Prescriptions for Anti-Malaria.

Youyou’s team finally returned to Beijing. At first, Youyou was heartbroken when her daughter didn’t recognize her and hid from her. But she nonetheless threw herself back into her work. Her team began distilling the most viable prescriptions into 380 herbal extracts they could test on malaria-infected mice. One of their biggest challenges was overcoming the primitive conditions of their own lab. They were forced to use household pots and pans as equipment, their facilities were poorly ventilated, and exposure to harsh organic solvents caused them all health issues. Tu would later reminisce, “It was a very laborious and tedious job, in particular when you faced one failure after another… However, we did receive encouraging comments in a telegraph from the most respected Premier Zhou Enlai.”

By 1971, the team was fairly certain it should focus solely on the herb quinghao, or sweet wormwood. Its first mention as a medicinal herb dated back 2,000 years to a silk scroll from the Han Dynasty called Prescriptions for 52 Kinds of Diseases. But quinghao cropped up frequently as an ingredient in remedies for intermittent fevers – a symptom of malaria – in multiple medical texts throughout the centuries. Still, there were many unanswered questions: Which species of quinghao? From what region of China? When should the plant be harvested? And which part should they use? Other research groups in Project 523 joined the quest. Through a painstaking process of elimination, Artemisia annua L was found to be the only variety of quinghao containing antimalarial properties. Yet no extraction of it ever produced a consistent, positive effect on malaria-infected mice.

Project 523 seemed to hit another dead end.

Frustrated, Youyou turned once again to ancient texts for clues. She reread a medical manuscript from the East Jin Dynasty, written in 340 by Ge Hong called A Handbook of Emergency Prescriptions to be Kept Up One’s Sleeve. Ge Hong advised: “A handful of quinghao immersed in two liters of water, wring out the juice, and drink it all.” Youyou was suddenly thunderstruck: Ge Hong steeped his quinghao in cold water! They had been boiling quinghao at high temperatures. Hot water was no doubt damaging the herb’s active ingredients. Her team immediately modified its extraction methods with lower-temperature solutions. Sure enough, on October 4, 1971, they finally found an extraction – Sample No. 191 – that proved to be 100% effective in curing malaria- infected mice. They began testing infected monkeys, and it again proved effective. In early 1972, they called their new drug Artemisinin.

The next step was, of course, to begin testing humans. To speed things along, Youyou and her team volunteered to use themselves as test cases, confident that 2,000 years of Chinese medicine couldn’t be wrong. By August of 1972, Youyou was able to journey back to Hainan to perform clinical trials of Artemisinin on 30 malaria patients.

It would take another five years of intensive chemical analysis before Artemisinin’s molecular structure could be isolated. By 1981, Youyou felt confident enough in the drug to present it at a World Health Organization meeting on malaria in Beijing. And in 1986, the Chinese Ministry of Health finally granted Artemisinin status as an officially approved drug. It had taken 15 long years for Mao’s secret Project 523 to produce a cure. But it was one that would ultimately save millions of lives. Throughout Youyou’s career, she has continued to use the strategy of building on the knowledge of the past to create solutions for the future. She is a research scientist, pharmacologist, educator – and now Nobel Laureate – but she considers herself, first and foremost, a lifelong student.

Download a free copy of the full book and accompanying lesson plan for your classroom.