The world’s medicine
chest is on fire, and we don’t even
know what’s inside it yet.
The world’s medicine chest is on fire, and we don’t even know what’s inside it yet.
Western medicine is the most successful system of healing ever devised and is becoming more so as technology improves and synthetic medicines proliferate. But Mother Nature has been synthesizing weird and wonderful medicinal chemicals for over three billion years, many of which chemists could not predict or devise in their wildest dreams.
They should go to the Amazon.
Over more than three decades, I’ve worked, collaborated and lived with the forest’s shamans as I learned some of their secrets. In the dreamscape of Amazonia flourishes an abundance of astounding species of plants and animals that have provided society with a pharmacopoeia of medicines of astonishing range, from contraceptives to treatments for high blood pressure and malaria, a dental analgesic and surgical muscle relaxants and chemicals that expand the mind.
The region is so vast and impenetrable that much within it remains undiscovered. No wonder the richness of the landscape and the impressive medicinal knowledge of the Indigenous peoples inspired bewilderment and wonder in early visitors from Europe.
As early as the 1600s, the Dutch physician Willem Piso observed several “very effective” local treatments in Brazil, writing, “These Indigenous people, in spite of their total lack of scientific training, have passed on many noble, secret antidotes and medicines unknown to classic science to the next generation.”
Today the region’s magnificent forests are being destroyed and its Indigenous cultures disrupted and extinguished ever more rapidly. But the medicinal potential of Amazonia is actually rising, because new technology allows us to find, isolate, evaluate, manipulate and employ natural products faster than ever.
If we can outrun the destruction, we will not have to choose between the microchip or the medicine man. Both can lead us to new cures, if approached in a responsible and ethical manner.
Our ignorance about Amazonian flora and fauna remains staggering. A recent study estimates there are about 16,000 species of trees in Amazonia, of which several thousand have not even been named by scientists, much less evaluated for medicinal potential.
Scientists cannot even agree on how many species of plants and animals and fungi inhabit the South American rainforest. We are collecting new species almost faster than we can identify them: In late July, a panel estimated that we find a novel species in Amazonia every other day.
These discoveries are not merely tiny fungi and insects. In just the past few years, researchers have discovered such seemingly obvious creatures as a new species of river dolphin, two novel species of electric eels, a cobalt blue tarantula and the loftiest tree in Amazonia, which is almost 100 feet taller than the previous record-holder. In a world where records are typically broken by seconds or inches, this latter find clearly demonstrates how much remains to be learned.
Wonders abound. One is the green monkey frog. Laboratory analysis of its skin has yielded several new proteins, two of which have been investigated as potential means of increasing the permeability of the blood-brain barrier, an important physiological challenge for delivering medicine directly to the brain — one of the holy grails of modern medicine.
Two other novel groups of proteins found in the same frog are antimicrobial, which might help fortify our arsenal of antibiotics; bacteria resistance to commonly used ones is a serious and growing problem in American hospitals. Most striking was the isolation from the frog of a new opioid, dermorphin, which is 40 times more potent than morphine.
While it may one day serve as the basis for a new and nonaddictive painkiller, it has already proved its utility in a lucrative and sinister manner: doping thoroughbreds. Investigators found that dermorphin was being administered to racehorses to make them run faster without pain; the substance was undetected by standard drug screens.
To better comprehend the pharmaceutical cornucopia potentially available in Amazonia, we need to expand our scope far beyond the archetype of the Western scientist searching for medicinal plants and animals known only to rainforest shamans. Some of the most intriguing leads derive from harmful or dangerous creatures either not used or even avoided by rainforest peoples. In the words of the 16th-century Swiss physician Paracelsus, the father of toxicology, the difference between a deadly poison and a lifesaving medicine may be only a matter of dosage. Hence a growing interest in studying the poisonous plants, animals and fungi of Amazonia.
Even when a poison or other peculiar compound cannot be converted into a medicine, it may teach us something new: The synthesis of A.Z.T., the first effective treatment for H.I.V., was inspired by unique compounds extracted from a Caribbean sponge. Venoms, with which Amazonia is amply stocked, have played a vital role in helping us understand how medicines function in the human body, particularly the nervous system. For example, the Amazon rainforest harbors approximately 75 species of the spectacularly colored poison dart frogs. More than 400 novel alkaloids — a class of biologically important chemicals that include cocaine, caffeine and strychnine — have already been found in their skin. The study of these new compounds is leading to a better understanding of the function of local anesthetics, anticonvulsants, anti-arrhythmics and even some toxins in the human body.
The Amazon is home to more than a dozen species of venomous snakes, mostly pit vipers from the rattlesnake family. One species inhabiting grasslands southeast of the Amazon wields a venom that causes a rapid drop of blood pressure in the unfortunate victim. Study of this compound resulted in the synthesis of captopril, one of the most effective and lucrative drugs ever devised, which in turn helped spawn an entire class of blood pressure drugs — ACE inhibitors, which have saved the lives of millions with hypertension.
An equally fearsome creature is the dreaded Amazonian wandering spider, perhaps the deadliest spider on Earth. The Amazon abounds in spiders — current estimates are about 3,000 species — and their venoms tend to be extraordinarily complex cocktails of proteins, dangerous peptides and other toxins. One component of the wandering spider venom is now being investigated as a treatment for erectile dysfunction. At the same time, Amazonian scorpions are receiving increasing attention for their pharmaceutical potential, particularly for their analgesic and antimicrobial promise.
Other intimidating Amazonian fauna have generated potentially important therapeutic leads, including the vampire bat and the giant caiman leech, 18 inches long. Both consume blood: the bat by slicing the skin of the victim and slurping from the wound, and the leech by attaching itself to a host and sucking blood out through a syringelike organ. And each carries a unique anticoagulant in its saliva: The leech produces hementin, and the bat draculin.
Given that heart attacks and strokes probably kill more people in the industrialized world than any other category of disease and that strokes are a leading cause of disability among older people, there is an urgent need to find and develop new drugs that can enhance or retard blood clotting. Both of these compounds showed promise in early clinical trials but did not make it to market. Nonetheless, research on Amazonian creatures like these and their unique compounds can provide new insights into the coagulation process that could lead to new and better synthetic drugs.
From a global perspective, fungi are the least-studied group of organisms with the greatest potential. They have already given us the most important class of drugs ever discovered — antibiotics. More recently, the fungal kingdom provided us with another blockbuster class of pharmaceuticals: statins, cholesterol-lowering drugs that rank among the most important and widely used medicines in the industrialized world today. Though both of these classes of pharmaceuticals were derived from temperate-zone fungi, tropical regions like Amazonia harbor many more species.
Once again, Western science knows very little about the potential utility of tropical fungi. Ethnobotanists in western Amazonia have often encountered piri-piri, a strange-looking sedge — a flowering, grasslike plant — reputed to feature many medicinal qualities. Detailed research in Peru with Indigenous colleagues by the American ethnobotanist Glenn Shepard unlocked the secret: The medicinal virtues attributed to this relatively chemically inert plant actually come from a fungus that infects it. Lab research revealed that this Amazonian fungus produces eight novel alkaloids related to L.S.D., and it is employed by Indigenous peoples to treat headaches and snakebite wounds, and to enhance coordination, control fertility and stanch birth-related hemorrhaging. Dr. Shepard considers piri-piri a sort of “ginseng of the Amazon,” because of its multifaceted, panacea-like medicinal uses. Thousands and thousands of fungi in Amazonia remain unstudied, their medicinal potential unknown.
The most significant major medical development in the past few years involving tropical organisms is the mainstreaming of hallucinogens into Western medicine. They represent the ultimate tools of the Indigenous shaman, who employs these plants and fungi like biological scalpels to investigate, diagnose, treat and sometimes cure ailments that have a partial emotional or spiritual basis. This is why these healers can often alleviate a medical problem unresponsive to therapies employed by Western physicians.
The use of these chemicals is rapidly gaining acceptance in traditional clinical settings. Many initial efforts have focused on the use of hallucinogens administered by Indigenous shamans: mescaline, psilocybin and ayahuasca — the latter from the Amazon. These mind-altering remedies have been clinically shown to produce promising therapeutic effects in some cases of addiction, depression, obsessive-compulsive disorder and end-of-life anxiety in terminal cancer patients.
Further formal studies are likely to take place for the treatment of anorexia, early stages of Alzheimer’s disease, insomnia, intractable pain and PTSD. This newfound interest in hallucinogenic therapies is not only improving our understanding of the human mind but also driving an enhanced appreciation of shamanic healing practices. And this shamanic therapeutic wisdom is not limited to hallucinogens: A single shaman may know and use 300 different plants for healing purposes.
Ultimately, the question has to be asked: Who should benefit first and foremost from the pharmaceutical treasures of Amazonia?
The answer is clear: the Amazonians. The Amazon is home to more than 30 million people, and almost all who live outside the very few large cities rely to some degree on the great forest as a source of medicines.
Unfortunately, they are the ones who suffer most when the forest is destroyed or degraded. They should have access to the therapeutic compounds and should share in the profits of the commercialization of these species. So should local communities and governments. The issue of proper respect for intellectual property rights must be of paramount concern.
A concrete example of how this should function is the case of the tree Sangre de Grado. Its healing sap is a staple component of many shamans’ botanical medicine cabinet. A compound from that tree — crofelemer — was approved by the U.S. Food and Drug Administration as the first antidiarrheal drug for H.I.V./AIDS patients. It is currently being evaluated for chemotherapy-induced diarrhea, as well as other potential applications. Every effort is being made to share the benefits of this drug with local communities, including generating employment through reforestation. This type of reciprocity, absent in most previous efforts where pharmaceuticals were developed from Indigenous rainforest societies, should be mandatory for all similar efforts going forward.
The entire world pays a price if the continuing destruction of the rainforest proceeds unabated, not just in terms of the very real disruptions and economic costs of climate change, but also in cures forgone as the forest burns, just so that the world can have more cheap beef and soy.
I have been unable to return to the Amazon since March. But through WhatsApp, I can sometimes communicate with the shamans I’ve long known. They tell me they are taking immunostimulating plants to keep the coronavirus at bay, though the effectiveness of this treatment has yet to be independently verified. As they do, the medicine quest continues: The shamans are combing the healing forest for plants that could be an effective treatment for people in their communities infected with the virus.
But with the advent of the burning season in Amazonia, which is caused by rampant deforestation, their medicine chest is on fire.
Mark J. Plotkin is an ethnobotanist and president of the Amazon Conservation Team, which works with local communities to protect the Amazon forests and traditional cultures. He is the author, most recently, of “The Amazon: What Everyone Needs to Know.”
Cover photo by Dado Galdieri/Bloomberg. Cover inset photo by Andia/Universal Images Group via Getty Images.
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Originally published by the Amazon Conservation Team: Source