Phytochemical Characterization and Antioxidant Activity Evaluation for Some Plant Extracts in Conjunction with Pharmacological Mechanism Prediction: Insights into Potential Therapeutic Applications in Dyslipidemia and Obesity

Abstract

Lipid metabolism dysregulation can lead to dyslipidemia and obesity, which are major causes of cardiovascular disease and associated mortality worldwide. The purpose of the study was to obtain and characterize six plant extracts (ACE-Allii cepae extractum; RSE-Rosmarini extractum; CHE-Cichorii extractum; CE-Cynarae extractum; AGE-Apii graveolentis extractum; CGE-Crataegi extractum) as promising adjuvant therapies for the prevention and treatment of dyslipidemia and its related metabolic diseases. Phytochemical screening revealed that RSE was the richest extract in total polyphenols (39.62 ± 13.16 g tannic acid/100 g dry extract) and phenolcarboxylic acids (22.05 ± 1.31 g chlorogenic acid/100 g dry extract). Moreover, the spectrophotometric chemical profile highlighted a significant concentration of flavones for CGE (5.32 ± 0.26 g rutoside/100 g dry extract), in contrast to the other extracts. UHPLC-MS quantification detected considerable amounts of phenolic constituents, especially chlorogenic acid in CGE (187.435 ± 1.96 mg/g extract) and rosmarinic acid in RSE (317.100 ± 2.70 mg/g extract). Rosemary and hawthorn extracts showed significantly stronger free radical scavenging activity compared to the other plant extracts (p < 0.05). Pearson correlation analysis and the heatmap correlation matrix indicated significant correlations between phytochemical contents and in vitro antioxidant activities. Computational studies were performed to investigate the potential anti-obesity mechanism of the studied extracts using target prediction, homology modeling, molecular docking, and molecular dynamics approaches. Our study revealed that rosmarinic acid (RA) and chlorogenic acid (CGA) can form stable complexes with the active site of carbonic anhydrase 5A by either interacting with the zinc-bound catalytic water molecule or by directly binding Zn²⁺. Further studies are warranted to experimentally validate the predicted CA5A inhibitory activities of RA and CGA and to investigate the hypolipidemic and antioxidant activities of the proposed plant extracts in animal models of dyslipidemia and obesity.

Keywords: UHPLC-MS; anti-obesity; carbonic anhydrase 5A; free radical scavenging activity; heatmap correlation matrix; hypolipidemic activity; molecular docking; molecular dynamics.

Figure 1

Heatmap correlation matrix and correlation spectrum (moderate correlation: [0.40–0.69]; strong correlation: [0.70–0.89]; perfect correlation: [0.90–1.00];│r│ = absolute value of Pearson correlation coefficient; INVSQRT = inverse square root transformation of data; SQRT = square root transformation of data).

Figure 2

Pyramid model for the ABTS method.

Figure 3

Pyramid model for the DPPH method.

Figure 4

Pyramid model for the FRAP method.

Figure 5

Predicted binding poses of RA and CGA in CA5A active site. (a) Predicted conformation of RA-CA5A complex; (b) 2D diagram of predicted interactions between RA and CA5A; (c) predicted conformation of CGA-CA5A complex; (d) 2D diagram of predicted interactions between CGA and CA5A. Green dashes—hydrogen bonds, blue dashes—hydrogen bond with water molecules, orange dashes—attractive charges, purple dashes—pi-sigma interactions, pink dashes—pi-alkyl interactions, light green circles—van der Waals interactions.

Figure 6

MD results after 100 ns of simulation time. (a) RMSD values for all protein carbon atoms as a function of simulation time for CA5A-RA vs. control; (b) RMSD values for all protein carbon atoms as a function of simulation time for CA5A-CGA vs. control; (c) Ligand movement RMSD after superposing on the receptor for RA and CGA, illustrating the movement of the ligand in the binding pocket; (d) Ligand conformation RMSD after superposing on the initial ligand coordinates, illustrating the conformational changes of the ligand; (e) RMSF values per amino acid residue for CA5A-RA complex vs. control; (f) RMSF values per amino acid residue for CA5A-CGA complex vs. control.

Figure 7

Ligand binding pose after 100 ns of simulation. (a) Superposition of the final snapshot of CA5A-RA complex simulation (blue/purple) on the initial conformation (green/orange); (b) 2D diagram of molecular interactions between RA and CA5A after 100 ns; (c) Superposition of the final snapshot of CA5A-CGA complex simulation (blue/purple) on the initial conformation (green/orange); (d) 2D diagram of molecular interactions between CGA and CA5A after 100 ns. Green dashes—hydrogen bonds, blue dashes—hydrogen bond with water molecules, orange dashes—attractive charges, magenta dashes—pi-pi T-shaped interactions, pink dashes—pi-alkyl interactions, tea green dashes—carbon–hydrogen bonds, light green circles—van der Waals interactions.