Researchers from ICVS have discovered that compounds originated from the plant Hemerocallis citrina Baroni could have therapeutic potential for treating neurodegenerative diseases like Machado-Joseph Disease (MJD/SCA3) and Frontotemporal Dementia with Parkinsonism (FTDP-17). These diseases are characterized by the loss of neurons and severe motor difficulties.
The study, published in the International Journal of Molecular Sciences, used Caenorhabditis elegans models (a type of worm commonly used in scientific research) to test different extracts of the plant. The results showed that an ethanolic extract of H. citrina significantly improved motor problems in these disease models. The positive effect was linked to the action of a neurotransmitter called serotonin, which is important for brain function. When serotonin receptors were removed from the models, the extract’s benefits disappeared, indicating that serotonin is crucial for the observed effect. Interestingly, the extract did not significantly affect the dopamine system, another important neurotransmitter.
Additionally, the researchers found that the plant extract activated a protein called HLH-30/TFEB, which regulates important cellular processes like autophagy and lysosome biosynthesis. These processes are vital for brain function and is often impaired in neurodegenerative diseases. The activation of this protein also depended on serotonin, reinforcing the idea that this pathway could be a promising target for treatment.
Phytochemical analysis revealed that the extract is rich in compounds such as hydroxycinnamic acids and flavonoids, with small amounts of epicatechins and quercetin derivatives. When tested individually, quercetin and isoquercitrin also helped improve motor function and activate the HLH-30/TFEB protein in the disease models.
Although the results are promising, the researchers emphasize that more studies, particularly in mammalian models, are needed before considering the clinical use of these compounds as a treatment. However, this study highlights the importance of medicinal plants as a source for novel treatments for complex brain diseases.
Authors: Jorge H. Fernandes, Marta Daniela Costa, Daniela Vilasboas-Campos, Bruna Ferreira-Lomba, Joana Pereira-Sousa, Qiong Wang, Andreia Teixeira-Castro, Xinmin Liu, Fengzhong Wang, Alberto C. P. Dias, and Patrícia Maciel.
