Research Highlight

Garden plant may hold promise for Alzheimer’s disease

doi:10.1038/nindia.2021.88 Published online 23 June 2021

The Clitoria ternatea plant.

.© Wikimedia Commons

Researchers from the National Centre for Biological Sciences have made use of tiny free-living soil worms called Caenorhabditis elegans and the ornamental butterfly pea plant Clitoria ternatea to find a potential treatment for Alzheimer's disease (AD)1.

AD, a neurodegenerative disorder marked by brain cell death and the shrinking of the brain, is the most common cause of dementia and cognitive impairment. Neurons in the human brain synthesise a protein called amyloid-beta (Aβ). In patients with Alzheimer's, these proteins undergo a process called aggregation, where they form large deposits (plaques). The aggregates impair the important tasks neurons need to carry out.

The Bengaluru-based researchers said this neurotoxicity could also be duplicated in the worms C. elegans, manifesting as paralysis in their muscles. The plant C. ternatea – commonly found in many Indian gardens with its charming blue and white flowers – is used in traditional Indian medicine. The research team extracted and isolated a set of ultra-stable cyclic peptides (or "cyclotides") from the plant. They tested these peptides on the worms and recorded the impact on their neurons.

They found the worms fed on the cyclotides showed significantly less paralysis than the ones that did not, showing that the cyclotides from the plant protected the neurons against amyloid aggregate formation.

“Neurodegenerative diseases are difficult to study in humans for a number of reasons and C. elegans offers an ideal solution,” the researchers concluded. “That the cyclotides found throughout the butterfly pea plant could become one therapeutic solution for neurodegenerative diseases has exciting potential in the paradigm of medicine and drug discovery.”


References

1. Neha V. Kalmankar et al. Disulfide-rich cyclic peptides from Clitoria ternatea protect against β-amyloid toxicity and oxidative stress in transgenic Caenorhabditis elegansJ. Med. Chem. (2021) DOI: 10.1021/acs.jmedchem.1c00033