A popular Chinese sage herb has been shown to contain similar active ingredients to compounds used in Western medicine to treat Alzheimer's disease.
The dried root of Salvia miltiorrhiza is called Danshen and has been used in the treatment of cerebrovascular disease for over one thousand years. It is also known as Chinese sage.
Researchers from King's College London, speaking at the British Pharmaceutical Conference last week, said they had found four compounds isolated from an extract of the root to be acetylcholinesterase inhibitors. This is the same pharmacological action as drugs marketed to treat Alzheimer's disease.
The compounds were shown to be chemically different from previously-identified acetylcholinesterase inhibitors.
Professor Peter Houghton, from King's College London, said: "Danshen is a common ingredient of Chinese prescriptions. It has many uses, one of which is to'prolong active life'. Our data provide some justification for this traditional use."
In the UK, Danshen is prescribed in Chinese clinics and is also available from Chinese herbalists. As part of its medicinal plant research, the King's research team has also investigated Korean herbal medicines.
The Conference heard that analysis of seven herbs with a reputation for treating memory-related disorders has found some of these to also have acetylcholinesteraseinhibitory activity. The researchers are currently working to identify the compounds in Korean herbs that produce this effect.
Alzheimer's is the most common form of dementia and affects an estimated 10 million people worldwide. Many of the current drugs taken to treat the disease, such as donepezil, have unpleasant side effects and doctors are keen to find alternatives. Sage is thought to be safe when taken in supplement form.
Researchers from the Medicinal Plant Research Centre at the Universities of Newcastle and Northumbria, UK, recently reported that healthy, young adults who took sage oil capsules performed significantly better in a word recall test than those who took placebo pills.
BPC 2003 took place at the Harrogate International Centre from 15-17 September 2003.