There is no medicine today that can cure a person who has contracted AIDS- an acronym for Acquired Immune Deficiency Syndrome. A person may be infected by the human immunodeficiency virus (HIV) and yet may not become patient of AIDS for some time. There is also no medicine available to delay the onset of AIDS in persons who have been infected with the HIV. This has changed since this article was written.
Plants have come into this field of work because some plants have been associated with the property of inducing immunostimulation. These plants reportedly increase resistance to disease, have an anti-stress effect and generally are thought to improve the quality of life. It is possible that some plants could delay the onset of AIDS in people who are virus. This line of thinking has prompted an international effort in the search for plants which may be useful in the treatment of HIV positive people. In spite of claims being regularly made, there is no plant which has clearly been shows to have this effect till date.
Hopes should not be raised as indication of activity will need many years before it can be used as a medicine. However it would be interesting to know something of what is happening in this field. The world Health organization has listed several plants which are being clinically evaluated for this type of activity. The National Institutes of Health, Bethesda, USA is willing to test in the laboratory but not on humans, any plants from anywhere in the world if there is some evidence that it may be useful. Unfortunately effectiveness in the test tube or what is known as “in vitro” activity is no certainty that it will have the same activity outside the test tube or in humans.
The National AIDS Control Organisation and the Indian Council of Medical Research have also set up a system for assessing claims mode about plants being able to counteract AIDS.
At a meeting held at the India International Centre in April 1993, seven Indian plants were identified which needed to be tested for anti-AIDS activity. These plants are well known – i) Ocimum Sanctum (tulsi), ii) Withania Somnifera (ashwagandha), iii) Boerhaavia diffusa (punarnava), iv) Tinospora cordifolia (giloya), v) Asparagus racemosus (satavari), vi) Bacopa monniera (nirbrahmi) and vii) Centella asiatica (brahmi). In fact these were dubbed by the press as the Big Seven.
These were selected because of different reasons but one reason was that all these plants were supposed to stimulate the immune system. The results of several studies with these plants have recently been published in the book HIV/AIDS and Traditional Medicine.
Several plants are being clinically evaluated for anti HIV activity outside India and five of these will be mentioned. Two plants are being tested in Japan. One is Glycyrrhiza uralensis known as sho-saiko-to. It has been used to treat viral hepatitis in that country. The second plant is Lentirus edobes. It has been used earlier for the treatment of cancers.
A compound tricosanthin, known as Compound Q has been isolated from the plant Trocosanthes kirilowii – the Chinese cucumber. This substance, Compound Q, is being clinically evaluated both in China and, interestingly enough, in USA which has to some extent, waived the usual preclinical toxicological studies needed before a plant substance can be tried on patients in that country.
The plant Diospyros usambarensis is being used if East Africa for the treatment of AIDS. It is usually present in any combination of plants given for this purpose.
The other plant which is used is Glycyrrhiza uralensis. It is widely used in Tanzania. All of us hope that one of these plants or more than one, administered alone or in combination, will be able to delay the onset of AIDS in HIV positive people.
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