TRADITIONAL CHINESE MEDICINE

ROBERT YUAN AND YUAN LIN

Ancient practices offer a complementary
approach to modern Western medicine

For those of us of Chinese descent, traditional Chinese medicine (TCM) is an important part of our cultural heritage. Many of us have some degree of familiarity with TCM practices, which are aimed at maintaining health and preventing disease by combining lifestyle practices (e.g., diet, exercise, meditation), physical manipulations (e.g., massage and acupuncture), and herbal formulations. Although “TCM” normally refers to the whole spectrum of traditional Chinese medicine, the acronym is used here to refer to that part of TCM relating to traditional Chinese herbal formulations.

Chinese medical practices date back thousands of years. The world’s first known medical document was Nei Jing, the Yellow Emperor’s Classic of Internal Medicine. Compiled in the 3rd century BC, the volume recounts a series of conversations about medicine between the Emperor Huang Di and his court physician. A century later, during the Han Dynasty, Shen Nong wrote the first known guide to herbal medicine, summarizing the pharmacological effects of some 365 substances.

In the modern era, in which new drug treatments and enhanced diagnostic and treatment technologies bring whirlwind changes to the field of medicine, there is new interest in TCM. Both of the authors were trained in the use of cell and molecular biology and biochemistry in modern Western medicine, and have clinical experience in these areas. Seen through the lens of biology and biochemistry, TCM seems to lack a scientific basis and falls more into the realm of myth. Yet, in an early exposure to traditional Chinese medical practices in 1976, we were present in an operating theater at a major Beijing medical center as brain surgery to remove a large tumor was carried out using acupuncture as the sole anesthetic procedure. Whatever we and a visiting team of US Army surgeons from Walter Reed Hospital thought of the theoretical foundations for acupuncture, we had to accept that the procedure was medically effective.

Global interest in TCM has increased significantly in recent years, driven by global trends in health care. About five years ago, the World Health Organization adopted a major policy change in accepting that most developing nations would have to make use of more traditional medical practices (rather than Western medicine) for primary health care. About the same time, the government of the People’s Republic of China, which had been promoting Western medicine in China, shifted towards increased emphasis on TCM. In both cases, the higher cost and relative unavailability of Western facilities, equipment, and pharmaceuticals, as well as staff trained in Western medicine, played a major role in these policy changes. Indeed, blending TCM practices with cutting-edge medical practices is common among many Chinese, both in China and abroad.

TCM relies on the vast amount of trial-and-error medical knowledge over a 4,000-year timeframe.

Much of mainstream America, however, tends to view TCM and its potential applications with some degree of skepticism. While acupuncture and massage may be accepted by many Americans as a potential treatment for body aches and pains, the holistic approach of TCM is not understood widely. The reluctance of Americans to accept TCM herbal preparations is based not only on a lack of scientific and clinical validation, but also on fundamental philosophical differences. Westerners and Chinese tend to look at health and disease in fundamentally different ways (See Table, page 43). In seeking a chemical drug treatment, for example, a Western patient is looking to treat his or her disease or symptoms, with quick results. A Chinese patient, in contrast, would see the prescribed TCM treatment as part of a longer-term process to restore the body’s overall equilibrium.

In spite of these basic differences, both forms of medical practice share a common view that health is associated with homeostasis, or the process by which an organism maintains a state of balance. Western medicine makes use of modern technology and powerful drugs that consist of single chemical entities to deal with anomalies in target cells, tissues, or organs. Such forceful interventions often succeed, but at the cost of further loss of homeostasis, which is expressed as severe side effects. The Chinese emphasis on maintaining and restoring balance may be less effective with acute diseases, but may be more appropriate for disease prevention and treatment of chronic diseases without an unacceptably high level of collateral damage. If the ultimate goal of health care is to maintain health, fight diseases, and meet medical needs, an integrated approach may provide the optimal solution.

The processes by which both bodies of medical knowledge have evolved also are dramatically different. Western medicine follows a strictly defined and rational process, combining chemical analysis and synthesis, biological assays using enzymatic reactions or cellular systems, and animal tests. The final stages involve closely controlled clinical trials to determine the safety and efficacy of any new drug treatment. TCM, in contrast, is based on a philosophical and theoretical framework that does not reflect current views of modern science, but relies on the vast amount of trial-and-error medical knowledge accumulated within large populations over a 4,000-year timeframe. It can be argued, therefore, that TCM started empirically with the clinical experience, and is moving only now in the direction of scientific validation.

One must also consider that the authors of the most important Chinese pharmacopoeia were often physicians in the imperial court, and even ministered to the Emperor. It is most unlikely that a physician who did not restore the Emperor to health would be around to write such medical references.

THE SCIENCE OF TCM

Western medicine makes extensive use of drugs that consist of single chemical entities. This follows the principle of seeking the “silver bullet” that will act on a single organism or organ. The Chinese alternative is the use of medicinal herbs, usually in formulations that contain anywhere from 4 to 24 different herbs. The rationale is that disease is caused by a loss of homeostasis that involves more than a single function of the body or a particular organ. Thus, the treatment needs to be multifactorial.

TCM herbal formulations are designed to stimulate and enhance functionality, to suppress and counteract toxicity, and to avoid antagonism and incompatibility. The prescription is most often specific to the individual patient. The proper combination of herbs is based on a functional classification. For example, if two herbs are being combined, they can be classified in terms of:

Mutual Accentuation
Mutual Enhancement
Mutual Counteraction
Mutual Suppression
Mutual Antagonism
Mutual Incompatibility

For the most part, the American scientific establishment does not take TCM formulations seriously, considering TCM unscientific in its understanding of the human body and the nature of disease and effective treatments. The widespread adoption of TCM in the United States is impeded by a lack of quality control and the absence of scientific and clinical proof of their effectiveness by US standards.

Over the past few years, however, a number of laboratories have worked on establishing a scientific framework for the study of TCM. The goal of these efforts is to try to reconcile traditional knowledge and modern scientific methodologies. This process can be organized into a number of different steps:

Identification of raw materials—Plant species need to be identified properly. Within each species, there is considerable variability in the content of specific active compounds, depending on such variables as soil conditions, temperature, precipitation, and time of harvest. There also is limited understanding of the differences between medicinal plants grown in the wild, and those cultivated commercially. To be safe, plants used in TCM also should be free of both chemical and microbial contaminants.

Proper preparation—The National Cancer Institute and the US Department of Agriculture screened 35,000 samples of roots, fruits, and bark from 12,000 plant species during the 1980s. This screening, however, resulted in the discovery of only three new drugs. Such data contradicts the ancient pharmacopoeias of China, which contain thousands of therapeutic formulations. This contradiction can be resolved if Western scientists look at biological activities as resulting from a mixture of active compounds, rather than a single chemical entity. This means that efforts to understand the science behind TCM can be useful only if the preparation follows closely the conditions prescribed in the pharmacopoeia.

Chemical standardization—Each of the principal herbs should be standardized as to the content of the major active compounds (many of which might be unknown). The objective is to establish a chemical “fingerprint” that meets certain standards for each lot of a particular herb. The actual formulation always will be based on a mixture of such standardized herbs.

Biological assays—These laboratory tests should reflect the biological activity in vivo. The biological activity of standardized TCM herbal preparations should correlate with a particular chemical fingerprint. The objective is not necessarily to characterize and isolate the active compounds, but to ensure that each lot will always have the same biological activity.

Manufacturing—the procedures used in the laboratory must be able to be scaled up in order to produce enough material for testing, and to assure that proper standards for drug manufacturing can be met. The finished product also must be formulated in such a manner that they can be used easily on the patients.

Animal models—When the disease can be induced in an appropriate animal, the standardized TCM can be tested for its therapeutic effect.

Clinical trials—From the perspective of Western medicine, studies of a medication on patients is essential before it can be approved for human use. It is generally accepted by the US Food and Drug Administration (FDA) that TCM herbs that have been in long-term use are safe. Nevertheless, they need to undergo extensive tests to demonstrate efficacy against the particular disease. Such tests are time consuming and expensive.

A number of scientists are now realizing that, both in principle and in practice, such an approach can be carried out successfully in a manner consistent with modern scientific and medical practice. It is much more difficult, however, to convince American scientists and physicians since the mechanism of action of TCM formulations remains unknown. If understanding the multiple reactions that take place with a single chemical in the human body is difficult, the interaction between a complex mixture of chemicals and the human body is singularly intractable, even with today’s technology. Studies have shown that certain active compounds in TCM formulations can act synergistically to boost or lower its biological activities. It may very well be that the activity of TCM formulations at lower concentrations and with relatively fewer side effects may reflect the properties of such “medical cocktails.”

TCM AND THE US REGULATORY AND LEGAL FRAMEWORK

There is also a major challenge to be faced in complying with US regulations and laws. A major hurdle for TCM formulations involves their approval by the FDA. The required FDA protocols for clinical trials are designed to test the rapid action of chemical drugs, but may not fit the traditional treatment modes for TCM preparations. For example, one clinical study compared the effectiveness of the TCM formulation DGNTT with the standard treatment using indamethicin for acute gouty arthritis. Indamethicin eliminated the acute pain associated with the disease in 2-3 days, while no effect was noted with DGNTT. The conclusion was that DGNTT is ineffective. An alternative explanation can be that DGNTT is a much slower-acting therapeutic agent. Many TCM formulations might not give positive results using standard FDA clinical protocols, so an appropriate protocol should be adopted to reflect traditional Chinese usage.

Most of the drugs that are approved by the FDA are single chemical entities, which makes it fairly straightforward to have lot-to-lot consistency in any given drug and show that any production batch will have the same biological activity. It is far more difficult to assure lot-to-lot consistency and biological equivalence for a TCM formulation, but this can be achieved by establishing chemical standardization and matching a chemical fingerprint with biological activities. The FDA has been open-minded in allowing for such an approach. To date, however, no TCM formulations have been approved as drugs by the FDA.

Another obstacle is that no major pharmaceutical company would consider the development of a new drug without patent protection. This is a major obstacle since many of the TCM formulations have been in Chinese pharmacopoeias for centuries. In the eyes of the Patent and Trademark Office and many patent lawyers, TCM preparations are in the public domain and cannot enjoy patent protection. This perception is not completely true, as TCM formulations can be patented in one of three ways: manufacturing process; formulation into modern drug format; and partial fractionation into a drug cocktail that retains all of the desirable biological activities. To date, a number of TCM formulations have become commercially successful in the United States as dietary supplements, which generally do not rely on patent protections.

It is highly likely that in order for a TCM formulation to establish itself in the US market, it would have to create new precedents in our regulatory and legal framework. Such an effort would be lengthy and very expensive, and its outcome far from certain.

INTEGRATING THE BEST OF EASTERN AND WESTERN MEDICINE

Western medicine is premised on a science-based methodology that starts with the characterization and synthesis of active compounds and culminates in clinical trials. The “silver bullet” paradigm and an understanding of specific mechanisms are the foundations of this medical system. Its greatest successes have been in the treatment of acute conditions. TCM, in contrast, is based on a large body of empirical evidence for which, by and large, there is not a comparable scientific base. This should not, however, prevent TCM preparations from being used if proven to be safe and effective. This is particularly true since TCM is likely to be most useful in maintenance of health and treatment of chronic conditions.

In South Korea and parts of China, an integrated approach is being practiced out of economic necessity and, more importantly, to improve the quality of life. In this blended approach, cancer patients are treated first with chemotherapy, radiation, and surgery. The side effects—nausea, pain, and weight loss—are treated with Chinese herbs. These herbs eventually build up the patient’s immune system to fight off infections and rid the body of any remaining cancer cells. Stroke patients are treated first with Western drugs to stabilize the condition, while acupuncture and TCM preparations are used to regain functionality and prevent recurrence. Patients with Parkinson’s disease are treated with Western drugs, followed by acupuncture, massage, and herbs. These types of combined therapies result in various degrees of symptom relief, as well as a reduction in the dosages of Western medicine.

This approach may be of great benefit in the United States, where patients no longer would have to choose between Western medicine and TCM, but would be encouraged to integrate elements of both systems to maximize the treatment of their specific illness. Chinese cosmology is symbolized by the circle of Tao where yin and yang are opposites but indivisible, each transforming the other. This may prove to be an apt description of how Chinese and Western medicine will evolve in the years to come.

Robert Yuan (CC ’94) is professor of cell biology and molecular genetics at the University of Maryland, College Park. His wife Yuan Lin was formerly a laboratory chief at the Food and Drug Administration. They are actively involved in researching traditional Chinese herbal formulations as a platform for the discovery of new drugs.

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