African plant extract could be clue to new Alzheimer’s disease drug

Researchers at The University of Nottingham have suggested that a plant extract used for centuries in traditional medicine in Nigeria may form the basis of a new drug to treat Alzheimer’s disease.

In a new study, they said that the extract taken from the leaves, stem and roots of Carpolobia lutea, could help to protect chemical messengers in the brain which play a vital role in functions including memory and learning.

The tree extract, the study, published in the journal Pharmaceutical Biology, could pave the way for new drugs to tackle patient symptoms, but without the unwanted side-effects associated with some current treatments.

Alzheimer’s disease is the leading cause of dementia, a general term for a decline in mental ability severe enough to interfere with daily life, which is caused by damage to, or changes in the brain.

World Health Organisation (WHO) estimates that between five and eight per 100 people in the general population aged 60 and over will have dementia at a given time.

Subtle short-term memory changes can be an early symptom of dementia. A change in mood is also common with dementia. In addition, difficulty recognising people and places, finding right words or following storylines sometimes may be classic early symptom of dementia.

Researchers and drug companies are racing to find out new treatments for these disorders and have begun looking to plant extracts as a probable source of new drugs.

Commonly called cattle stick or poor man’s candle, Carpolobia lutea, is also refered to as Abekpok Ibuhu (Eket), Ikpafum, Ndiyan, Nyayanga (Ibibio), Agba or Angalagala (Igbo) and Egbo oshunshun (Yoruba).

Herbalists in Nigeria use its root as an aphrodisiac and in the treatment of genitourinary infections, gingivitis, and waist pains.

The Nottingham study found that the plant was highly effective in preventing the breakdown of acetylcholine, the chemical in the brain that control memory and attention.

It also had other beneficial antioxidant properties in fighting free radicals – unstable atoms that can cause damage to cells and contribute to ageing and disease, a damage that may be exacerbated in Alzheimer’s disease.

Current drugs – called acetylcholinesterase inhibitors – reduce the normal breakdown of acetylcholine. Extensive research is underway to find new versions of these drugs but with additional beneficial properties.

In the past, researchers from the Icahn School of Medicine at Mount Sinai in New York have suggested that minimally processed cocoa may also be helpful in preventing Alzheimer’s disease.

The researchers found that a cocoa extract – called lavado – may reduce or block damage to nerve pathways found in patients with Alzheimer’s disease. This means that symptoms of the condition – such as cognitive decline – could be prevented.

Researchers in this study published in the Journal of Alzheimer’s Disease, found that lavado cocoa extract reduced damage to nerve pathways in mice with Alzheimer’s disease and therefore suggested that the extract could pave the way for new drugs that prevent and treat the condition.

Professor Giulio Maria Pasinetti, the research team led stated that   “Given that cognitive decline in Alzheimer’s disease is thought to start decades before symptoms appear, we believe our results have broad implications for the prevention of Alzheimer’s disease and dementia.”

This study, according to the researchers, suggests that lavado cocoa extract could pave the way for such drugs, but further studies are needed to better determine how the extract works in the brain.

Furthermore, the team says it could be worth turning lavado cocoa extract into a dietary supplement, as it may provide a “safe, inexpensive and easily accessible” way to prevent Alzheimer’s disease.

Previously, intake of cacao has been associated with brain health. Researchers at Harvard Medical School in Boston, for instance, suggested that drinking two cups of hot chocolate a day may prevent memory decline in older adults.

Also, researchers at the Lewis Katz School of Medicine at Temple University (LKSOM) have also identified a specific ingredient that protects against cognitive decline in extra-virgin olive oil, a major component of the Mediterranean diet.

In a study published online June 21 in the Annals of Clinical and Translational Neurology, the researchers show that the consumption of extra-virgin olive oil protects memory and learning ability and reduces the formation of amyloid-beta plaques and neurofibrillary tangles in the brain — classic markers of Alzheimer’s disease.