Protection of Viola odorata L. against Neurodegenerative Diseases: Potential of the Extract and Major Phytoconstituents

Neurodegenerative diseases cause cognitive impairment owing to neuronal death and deterioration. Only a few brain-protecting chemical investigations yielded neuroprotective medications. Viola odoata L. is a traditional medicinal herb that has lately been shown to have strong pharmacological effectiveness against major neurological illnesses with fewer adverse effects. The objective of the current review is to provide a thorough overview of the key biologically active components and extract of Viola odorata L. in their capacity to safeguard nerve cells. Science Direct, PubMed, Springer Nature, and Google Scholar were scoured for relevant articles using the terms ``Viola odorata L.'', and in the heading and abstract or main text, ``neuroprotective activity'', ``neurodegenerative disease'', ``pharmacological potential'', and ``therapeutic activity'' along with ``extract'' or ``phytoconstituents''. Neuroprotective activity of Viola odorata L. extract or phytoconstituents were used to classify and investigate the articles that passed the screening process. A total of one hundred twenty one papers were reviewed based on the collected data. The following topics have been elaborated upon in the text: pathological factors of neurodegenerative diseases; role of medicinal plants in neurodegenerative diseases; Viola odorata L. taxonomy, pharmacological activities, toxicity and adverse effect; neuroprotective activity of extract and various active components of Viola odorata L. The primary phytocomponents of Viola odorata L. were discovered to be anthocyanins, flavonoids, melatonin, salicylic acid, cumarins and various alkaloids, which are primarily responsible for its neuroprotective action. These natural plant compounds can boost antioxidant levels, reduce harmful oxidants, alleviate nerve pain, decrease the production of pro-inflammatory cytokines such as IL-6, IL-1β, and TNF-α, lower the total amount of nitrite produced, and trigger various neuroprotective mechanisms in the nervous system. It has been also concluded in several investigations that Viola odorata L. extract and some of its major molecular components can protect against toxic affronts, either directly through neuroprotective mechanisms or indirectly through antioxidant properties. Despite the need for further research, the presence of bioactive components in Viola odarata L. that hold the potential to become effective neuroprotective therapeutic agents shows its potential use in treating neurodegenerat