Phytochemical Analysis, Network Pharmacology and in Silico Investigations on Anacamptis pyramidalis Tuber Extracts.

Abstract

Anacamptis pyramidalis (L.) Rich. forms part of the Orchidaceae family that is highly valued for its horticultural as well as therapeutic benefits. The present study set out to investigate the inhibitory activity of A. pyramidalis tubers against key biological targets for the management of type 2 diabetes, Alzheimer disease, and skin hyperpigmentation. In addition, the antioxidant potential of the extracts was also assessed using multiple methods. The detailed phytochemical profiles of the extracts were determined using high-performance liquid chromatography. Based on qualitative phytochemical fingerprint, a network pharmacology analysis was conducted as well. Parishin was identified from the water extract only, whereas gastrodin and caffeic acid derivatives were present in the methanol extract. The methanol extract exhibited high inhibitory activity against tyrosinase (69.69 mg kojic acid equivalent/g extract), α-amylase (15.76 mg acarbose equivalent/g extract), and α-glucosidase (20.07 mg acarbose equivalent/g extract). Similarly, the methanol extract showed highest antioxidant potential (22.12, 44.23, 45.56, and 29.38 mg Trolox equivalent/g extract, for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), CUPric Reducing Antioxidant Capacity (CUPRAC), and Ferric Reducing Antioxidant Power (FRAP) assays, respectively). Finally, the results of network pharmacology analysis, besides corroborating traditional uses of plant extracts in the management of cold and flu, confirmed a direct involvement of identified phytochemicals in the observed enzyme inhibitory effects, especially against tyrosinase, α-amylase, and α-glucosidase. Furthermore, based on the results of both colorimetric assays and network pharmacology analysis related to the activity of A. pyramidalis extracts and identified phytocompounds on enzymes involved in type 2 diabetes, a docking study was conducted in order to investigate the putative interactions of oxo-dihydroxy octadecenoic acid trihydroxy octadecenoic acid against aldose reductase, peroxisome proliferator-activated receptor (PPAR)-α, dipeptidyl peptidase (DPP)-IV, and α-glucosidase. Docking analysis suggested the inhibitory activity of these compounds against the aforementioned enzymes, with a better inhibitory profile shown by oxo-dihydroxy octadecenoic acid. Overall, the present findings supported the rationale for the use of A. pyramidalis as source of bioactive metabolites and highlight, today more than ever, for the strong necessity of linkage strategy between wild resource valorization and conservation policy.