Chemical Composition and Inhibitory Effects of Hypericum brasiliense and H. connatum on Prolyl Oligopeptidase and Acetylcholinesterase Activities

Title:Chemical Composition and Inhibitory Effects of Hypericum brasiliense and H. connatum on Prolyl Oligopeptidase and Acetylcholinesterase Activities

Volume: 12 Issue: 5

Author(s): Maura Z. dos Santos, Ionara I. Dalcol, Luciana Adolpho, Meritxell Teixidó, Teresa Tarragó, Ademir Morel and Ernest Giralt

Affiliation:

Keywords: Hypericum connatum, H. brasiliense, Clusiaceae, Prolyl oligopeptidase, Acetylcholinesterase, Dipeptidyl peptidase- IV, flavonoids, PAMPA assay.

Abstract: Background: The genus Hypericum (family Clusiaceae) comprises various species that are used in traditional medicine, such as wound healing, antidepressant, and anticancer agents.

Objective: The aim of this study was to evaluate the inhibitory capacity of extracts and fractions from two Hypericum species used in the Brazilian folk medicine (H. brasiliense and H. connatum) against the enzymes prolyl oligopeptidase (POP), dipeptidyl peptidase-IV (DPP-IV), and acetylcholinesterase (AChE), as well as to identify their main active constituents.

Methods: Dried aerial parts of H. connatum and H. brasiliense were subjected to extraction with 8:2 methanol-H2O. Each hydroalcoholic extract was fractioned resulting in ethyl acetate and aqueous fractions. The activity of POP, DPP-IV and AChE was determined in vitro in 96-well microplates.

Results: The main components identified in the plant extracts were chlorogenic acid (1), quercitrin (2), rutin (3), quercetin (4), and isoquercitrin (5). Hydroalcoholic extracts, ethyl acetate and aqueous fractions showed high POP inhibitory activity with IC50 values of 2.6 to 3.7 µg/mL. AChE and DPP-IV inhibitory effects were very low for all extracts and substances.

Conclusion: Chlorogenic acid (1) and quercetin (4) were the main constituent responsible for the activity observed against POP. Parallel artificial membrane permeability assay of ethyl acetate fractions of both species showed that the metabolite that can effectively pass through the lipid membrane is 4, the aglycone form of 2, 3 and 5.

Cite this article as:

Z. dos Santos Maura, I. Dalcol Ionara, Adolpho Luciana, Teixidó Meritxell, Tarragó Teresa, Morel Ademir and Giralt Ernest, Chemical Composition and Inhibitory Effects of Hypericum brasiliense and H. connatum on Prolyl Oligopeptidase and Acetylcholinesterase Activities, Medicinal Chemistry 2016; 12 (5) . https://dx.doi.org/10.2174/1573406411666151026121845