February 27, 2013

Three Cheers for Periwinkle: Ethnobotany, histiocytosis and Rare Disease Day

Just over seven years ago, my youngest son, then eighteen months old, woke up one morning with a lump exactly the size and shape of an olive behind his ear. An X-ray revealed a quarter-sized hole in his skull and a mass of dense tissue. The initial diagnosis -- malignant tumor of the cranium -- left everyone in the family reeling, incredulous and praying for a miracle. Within a few days and thanks to the incredible staff at the Boldrini Children's Hospital in Campinas, Brazil (if I ever become a millionaire I will leave my fortune to them), this diagnosis was rejected in lieu of something far stranger: Langerhans cell histiocytosis, also known as eosinophilic granuloma or histiocytosis-X (due its mysterious etiology), a childhood disease that is a hundred times rarer than leukemia and thus often misdiagnosed.

You know you are desperate when a doctor tells you your child has an extremely rare immune system condition of unknown origin that punches Swiss-cheese-like holes in the bones and especially the skull, fatal in about 15% of the cases and usually treated through experimental drug protocols, and you feel relieved.

Periwinkle: Our little miracle

His initial treatment included small doses of vinblastine, a drug derived from the caustic sap of the rosy periwinkle, Catharanthus roseus (or Vinca rosea), native to Madagascar. In a matter of days, the olive-sized lump looked more like a caper, and within six weeks the tumor was no longer visible to the eye. The treatment regime continued for another two years with a cocktail of drugs similar to those used for leukemia but in far smaller doses. 

I am very relieved to say that he is now fully recovered and suffered no side-effects from more than two years of low-dose chemotherapy. Miracles really do happen.

I owe this particular miracle at least in part to the wonders of traditional medicine and the rigors of ethnobotanical investigation. Vinblastine and other cancer-treating vinca alkaloids were discovered in the late 1950s by Canadian physician Robert L. Noble, whose brother Clark Noble, involved in the discovery of insulin, forwarded him a packet of medicinal leaves sent by a patient who had visited Jamaica and heard the plant was used there to treat diabetes. While the plant extract had little effect on glucose levels, it produced a powerful response in white blood counts and quickly became a mainstay in the treatment of many kinds of cancer.

The Madagascar or rosy periwinkle (photo: Wikipedia)

Despite the widely trumpeted promise of discovering novel cures with rainforest shamans -- remember that Sean Connery film, "Medicine Man"? -- research on medicinal plants in most Latin American countries has slowed to a standstill, though India and China race ahead. On the one hand, exaggerated concerns about "biopiracy" (some call it "bioparanoia") have scared many governments, particularly Brazil, into bureaucratizing and restricting bioprospecting to virtual paralysis, dampening once hopeful aspirations for economic development based on traditional knowledge and biodiversity.[1] On the other hand, technological advances have led drug companies to focus more on computer-based molecular modeling and gene therapy, and less on old-school natural products research. Finally, many traditional medicines address diseases of the poor, and so are of little interest to the profit-driven pharmaceutical industry.

I have often been impressed by the efficacy of native remedies.

During my own ethnobotanical work in Peru I used native Matsigenka remedies on myself to cure a medically diagnosed case of cutaneous leishmaniasis, the South American skin disease related to the dreaded, visceral Old World form of leishmaniasis known as kala-azar. However I stopped researching medicinal plants after moving to Brazil to avoid bureaucratic headaches and out of fear of biopiracy accusations.

Despite technological changes and a sometimes hostile research environment, new and important drugs are still being discovered through ethnobotanical investigation. An extract of Sangre de drago ("dragon's blood"), a tree sap used medicinally in the Amazon, was recently approved by the United States Food and Drug Administration for treating AIDS symptoms. Artemesin, now a last-ditch therapy for drug-resistant malaria, is likewise derived from a Chinese medicinal plant related to wormwood.

And so in recognition of International Rare Disease Day (February 28) and the Histiocytosis Association's campaign to improve diagnosis and treatment, I call attention to this rare childhood disease and to the role of traditional medicine and ethnobotany in its treatment. I also pause to give thanks for my own little (big) miracle. 



[1] Frickman, F. S. S. & A. G. Vasconcellos. (2010). Oportunidades para inovação e aproveitamento da biodiversidade amazônica em bases sustentaveis. T&C Amazônia 8(19): 20-28.


  1. What an incredible story. I am glad it turned out lucky, and I hope that the world learns to appreciate the healing powers of native plants.

    1. Thanks for your comment Kristina, yes we were lucky. Plants can do amazing things!

  2. Wow, Glenn, fantastic. Glad to hear things went as they did, and too bad the 'pipeline' has been stymied. Here' to hoping it opens up sometime soon.

    Chris Meserve

    1. Hi Chris, very nice to hear from you. It is sometimes difficult to achieve the proper balance between a country's desire to protect its resources from overexploitation, especially by foreign corporations, and the kind of research that can lead to life-saving discoveries. Unfortunately in Brazil, a series of negative experiences has led to a paranoid climate where very little research can get done. There is also the very tricky issue of helping indigenous people exert their own intellectual property rights. It's difficult but not impossible, the way to solve the problem is by trying different arrangements out and seeing what can be made to work, and not just shutting the whole process down. Thanks again! -- Glenn

  3. Impressive the magic of plants!! Hope your little one is doing well now. Bernadette

    1. Yes, he seems to be fully cured. But what a scare it was there for a few years... Thanks for writing, Glenn

  4. Glenn, thank you for the article and the information. Realmente reflejas al escribir tus sentimientos, sin sobrecargarlo! Gracias!
    Por otro lado, quizás estas posturas extremas contra la biopiratería se suavicen cuando los pueblos nativos sean los que exijan a los gobiernos ser parte de la investigación en nuevas curas y tratamientos. Aún hoy hablamos dos lenguajes y el mundo "profit-driven" del que hablas no va a parar su carro para escuchar otros saberes si es que no significa dinero de por medio...


  5. Yes, Armando, certainly the paranoia around biopiracy in tropical countries has strong historical precedents in colonialism, the story of rubber, and a few high-profile cases of bona-fide biopiracy. It is of course necessary and important that countries have sensible legislation to protect their genetic heritage and indigenous peoples' property rights (though the latter usually gets second schrift). Yet the key word is "sensible": the overreaction in Brazil for example virtually paralyzed not only pharmaceutical research, but most kinds scientific research into plants and animals for nearly a decade. Only in the past few years have more sensible solutions been proposed and in some cases implemented. But the train has already left the station, it would seem: the heyday of natural products research is now behind us, and both researchers and companies are now leery of initiating new work due to the potential for scandal. Thanks for your comment! Glenn

  6. We hope to see the day thinks going better for research and development by working on it, not neglecting it. Awareness on civilian society should improve the pression on the brazilian government for law changes on the access to genetic resource and its associated knowledge, once it intrinsically desagree of the principles of biodiversity conservation postulated in the so called Biological Diversity Convention, raised up at the ONU Conference on Environment and Development, in Rio92. Untill there I still sitting while waiting my CGEN authorization. Thanks, Camilo.

  7. Hi Glenn I feel so much about your little one. Hope your he is doing well now. Hugs
    - Vinnie