Antennaria dioica (L.) Gaertn. (Asteraceae): From Metabolite Profiling to Comprehensive Evaluation of In Vitro and In Silico Enzyme Inhibitory Activity

Antennaria dioica (L.) Gaertn., (tribe Gnaphalieae of Asteraceae family) is known in traditional medicine for treatment of biliary and respiratory ailments, and for its astringent and hemostatic properties. This work aimed at in-depth phytochemical profiling and in vitro antioxidant and enzyme inhibition assessment of methanol-aqueous extract from the A. dioica aerial parts integrated with molecular docking study. An ultra-high-performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-HRMS/MS) analysis revealed a total of 130 secondary metabolites including 39 acylquinic acids, 26 caffeoylhexaric acids, 34 carboxylic and phenolic acids and coumarins, as well as 31 flavonoids. For the first time, 68 core structures alongside caffeoylglucaric derivatives leontopodic acid A and B are reported in the species. The A. dioica extract inhibited α-amylase and α-glucosidase (0.45 mmol and 0.11 mmol ACAE/g, respectively), and acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) (1.93 and 1.14 mmol Galantamine equivalent per gram extract (GALE/g), respectively). The extract exhibited antioxidant activity in different in vitro assays. In search for bioactive compounds, the extract's identified molecules were docked within four target enzymes: AChE (PDB code 4EY7), BChE (PDB code 7AMZ), α-amylase (PDB code 1Z32), and α-glucosidase (PDB code 5NN6). Twenty three core structures showed favorable docking scores for α-amylase and α-glucosidase, while only 4 of them were relevant for AChE and BChE. Methylbutyryl- and p-hydroxybenzoyl-tricaffeoylglucaric acid alongside apigenin 7-O-caffeoylglucoside were highlighted to contain potential ligands of α-amylase and α-glucosidase. The Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADME/Tox) properties of the selected compounds were evaluated in silico. Apigenin 7-O-caffeoyl-β-glucoside was outlined as having good potential for interaction with α-amylase and α-glucosidase, and favorable ADME/Tox properties.