Trichilia catigua and Turnera diffusa extracts: In vitro inhibition of tyrosinase, antiglycation activity and effects on enzymes and pathways engaged in the neuroinflammatory process

• Type: Article in International Scientific Journal
• Date: 2021

Authors

Bernardo, J (Author) Other; Malheiro, I (Author) Other; Videira, RA (Author) Other; Patricia Valentao (Author) FFUP; Santos, AC (Author) Other; Veiga, F (Author) Other; Paula B Andrade (Author) FFUP

Journal

Title: Journal of Ethnopharmacology

Vol. 271

ISSN: 0378-8741

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 0 Citations

Scopus - 1 Citation

Other information

Authenticus ID: P-00T-E29

DOI: 10.1016/j.jep.2021.113865

Abstract (EN): Ethnopharmacological relevance: Flavonoids interact with multiple targets in Central Nervous System resulting in a broad neuroprotection mediated by complementary processes and synergic interactions. Therefore, flavonoidbased therapies may input positive outcomes in the prevention and early management of neurodegenerative diseases. In Brazilian folk medicine Trichina catigua is used for its neuroactive properties, such as neurostimulant, antioxidant and anti-neuroinflammatory, while Turnera diffusa is traditionally used as a tonic in neurasthenia. Both species are known to be rich in flavonoids. Aim of the study: To study aqueous extracts of T. catigua and T. diffusa in terms of their antioxidant and antiglycation effects, inhibition of tyrosinase activity, and interaction with enzymes and pathways engaged in neuroinflammation. Moreover, whenever possible, to establish a relationship between the studied activities and the traditional usage of the species. Materials and methods: The phenolic profiles of the aqueous extracts were validated by HPLC-DAD. The effect of the extracts over mushroom tyrosinase and 5-lipoxygenase activities, as well as their capacity to impair bovine serum albumin glycation, were assessed by in vitro assays. The anti-neuroinflammatory potential of the same extracts was evaluated by their capacity to mitigate the pro-inflammatory stimulus induced in BV-2 microglia cells by interferon-gamma. Results: T. catigua extract, a rich mixture of phenolic acids, catechins and flavonolignans, excels by its ability to decrease lipid peroxidation (EC50 = 227.18 +/- 9.04 mu g/mL), and to work as anti-glycation agent, and inhibitor of both tyrosinase and 5-lipoxigenase (IC50 = 358.84 +/- 19.05 and 56.25 +/- 14.53 mu g/mL, respectively). However, only T. diffusa extract, mainly composed by luteolin derivatives, is able to lower NO production by BV-2 microglia cells stimulated with interferon-gamma, despite its lower activities in the other assays. Conclusions: Overall, this work highlights the value of medicinal plant extracts as sources of bioactive flavonoidrich extracts with neuroactive effects. Furthermore, these results support their application as alternative strategies to develop functional foods and therapeutics to fight chronic neurodegenerative disorders.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8