Newsletter No. 86

CUHK Newsletter No. 86 4th April 1996 3 Department Update We Don't Play Nostradamus Pharmacologist Explains the Unpredictability ofDrugSearch Searching for New Drugs in the Plant Kingdom There are various groups at the University that are involved in isolating potential new drugs from nature, of which traditional Chinese medicines represent an important source. Prof. Robert Jones, chair of the Department of Pharmacology, compares this process to 'finding a needle in a haystack'. Yet it has not stopped him and his colleagues from combing the local Chinese herbal medicine shops for herbs. As part of the problem is the prevalence of adulteration in the marketplace, they also have connections in China who scour the hills for the authentic plants. These are no orientalized white-bearded gurus in the mountains who alone have the sacred key to all herbs since time immemorial, but experts from universities in China with a sharp eye for medicinal herbs. Samples of the herb are sent to the department and then begins the painstaking process of f i nd i ng the chemical structure of the herb, identifying its beneficial compounds if such exist, testing their mechanisms on the body, and determining the form in which the herb can be used as a drug. And of the hundreds and thousands of identified compounds in a herb, often only one or two, if any, are useful. A far more serious reason for the difficulty in finding natural remedies, as Prof. Jones points out, is the state of our environment: 'We are destroying the rain forests and, in doing so, our potential future drugs. Although we can make almost any compound synthetically, it's not as efficient as getting it from nature. The plant kingdom has yielded more drugs than we could possibly have got if we had made them ourselves. Plants contain substances which interact with mammalian systems and, in ways we still don't quite understand, the plant kingdom acts as a kind of filter which increases our chances of success in our attempts to find new drugs .' Studying the Effects of Drugs at the Cellular Level Interest in traditional Chinese medicines in the department started in the early 1980s under the direction of Dr. Kelvin Chan. Dr. Chan has since left for L i ve r pool and the interest is now continued by Profs. John Yeung, Alaster Lau, and Lin Ge, in collaboration with colleagues in the Department of Pharmacy and the Chinese Medicinal Material Research Centre. Enumerating the major changes in the department since his chairship, Prof. Jones says new research areas have been explored, which include inflammation research and research in anti-emetic drugs. Other projects of a more elementary scientific nature involve, to quote Prof. Jones, 'pinching o f f tiny pieces of cell membrane from the cell and looking at them to see what happens when the drug molecule interacts w i th the cell membrane' . Although such prolonged peering at our most basic selves may be less than gratifying for the moment, the knowledge obtained may hold promises for the future. However it is not for those who like to play Nostradamus. Prof. Jones explains, 'Often we can't tell what the benefit of a drug will finally be. We may be looking at a drug's effects on a blood vessel but eventually may find some other totally different use outside the cardiovascular system, for example, in the central nervous system, so it ends up being used as a tranquilizer. People would like to think they can predict but few are actually successful. They only tell you afterwards, you see .' The department has taken on the teaching of pharmacology to pharmacy students since the inception of the Department of Pharmacy in September 1992. The two departments have also collaborated in research, especially that involving compound isolation. Molecular Biology a Major Research Tool According to Prof. Jones, research in the department will gradually be moving towards molecular biology, which means identifying drug mechanisms using molecular biology techniques. However he advises pharmacologists to keep in mind that their primary concern is how drugs wo rk on body systems, and therefore they should take care not to steer too far away from the clinical situation. After all, 'manipulating test-tubes is a long way from what happens in the beating heart', as Prof. Jones succinctly puts it. It is indeed a long way and one which grazes the sensitive issue of animal- testing. Prof. Jones believes it is necessary to keep the hierarchy of testing: 'Wehave to take things by stages. After a potential drug is taken out of the test- tube, it has to be tested on the simple, then the complex, and then the very complex, which is the human being. I think the general public does not appreciate that most drugs don't get that far. Thousands of new compounds are synthesized every year, but very few actually get through this selection process: some have bad side effects, some are too shortlasting.... So when you come to the end of the line you may only have one drug out of five or ten thousand that actually makes it to a patient's arm.' Yearning for a Personal Approach Teaching in the department will also be going in new directions, one of which is the multi-media approach. Although Prof. Jones acknowledges the benefits of multi-media teaching, his own taste seems to lean towards the more personal and traditional. To quote him, 'nothing beats small-group tutorials by experienced tutors when it comes to teaching', yet he admits that gaining that experience may take years. Prof. Jones also laments the fact that lab sessions have been cut, sometimes due to financial considerations. 'The computer is seen as a substitute but it doesn't teach you manual skills except how to rattle keys,' he comments wryly. On the subject of the one-line budget, Prof. Jones points out that being one of the smaller departments in the University, the Department of Pharmacology cannot enjoy as much flexibility of spending as does a larger department under the one- line budget. He also finds the computerized system of organizing the department's finances to be non-interactive. Ever since he came to Hong Kong over five years ago, Prof. Jones has been living on the University campus. Does the Un i ve r s i ty give h im the sense of interaction and communication that he finds so important? ‘I feel more involved socially in this university than I did working in the UK. Maybe it's because I have been living on campus; or maybe it's because the campus is more compact — I ' m not really sure. In any case I definitely feel involved in the actual evolvement of the University. And this is quite nice,' says Prof. Jones with his usual candour. Piera Chen A graduate student of pharmacology analysing data on the computer