Modulatory actions of o-coumaric acid on carcinogen-activating cytochrome P450 isozymes and the potential for drug interactions in human hepatocarcinoma cells

Two new compounds from endemic Centaurea paphlagonica (Bornm.) Wagenitz and their cytotoxic activities

Centaurea paphlagonica (Bornm.) Wagenitz is an endemic plant in Turkey. Pyrocatechol, vanillic acid, 3,4-dihydroxy benzoic acid, 5-O-caffeoylshikimic acid, tamarixetin, chlorogenic acid methyl ester, quercetin, 1,3-dicaffeoylquinic acid, tamarixetin-7-O-β-D-glucopyranoside, quercimetrin, daucosterin, paphlagonicanin B, tamarixetin-7-O-β-rutinoside, rutin, chlorogenic acid, isoorientin, orientin, 3-O-feruloylquinic acid, quercetagetin-3-methyl ether 6-O-β-glucopyranoside, diosmetin 6-C-β-glucopyranoside, quercetagetin 4'-methyl ether 7-O-β-glucopyranoside, paphlagonicanin A, nepetin, cirsiliol, desacylcynaropicrin, and 8α-O-(2',3'-dihydroxyisobutyryl) desacylcynaropicrin were isolated from both flower and aerial parts of C. paphlagonica. These compounds were identified using 1D and 2D NMR methods and ESI-MS. The MTT assay assessed the antiproliferative activities of all isolated (known and new compounds) compounds on Caco-2, LNCaP, A549, HeLa, and HEK-293 cell lines. The 8α-O-(2',3'-dihydroxyisobutyryl) desacylcynaropicrin demonstrated the highest activity against CaCo-2 and HeLa cancer cell lines.

Drug interaction potential of Ankaferd blood stopper® in human hepatocarcinoma cells

BACKGROUND

Ankaferd blood stopper® (ABS) is an herbal extract consisting of mixtures of Alpinia officinarum, Gycyrrhiza glabra, Vitis vinifera, Thymus vulgaris, and Urtica dioica plants and has been used in recent years in Turkish medicine as a hemostatic agent. Despite its extensive usage, there is no information available about the drug interaction in HepG2 cells. The current work evaluated the effect of ABS on the expression of CYP1A1-1A2, CYP2E1, and CYP3A4 isozymes that are primarily involved in drug and carcinogen metabolism.

METHODS

We selected HepG2 cells as in vitro cellular models of the human liver. The cells were treated with different concentrations of ABS [0.25%-40% (v/v)]. A crystal violet staining assay was used to determine the cytotoxicity of ABS. We examined drug-metabolizing enzymes, including 7-ethoxyresorufin O-deethylase (CYP1A1), 7-methoxyresorufin O-demethylase (CYP1A2), aniline 4-hydroxylase (CYP2E1), and erythromycin N-demethylase (CYP3A4), in vitro in HepG2 cells. The expression (mRNA, protein) levels of drug-metabolizing enzymes were analyzed by qPCR and Western blotting, respectively.

RESULTS

The EC05 and EC10 values for ABS were 0.37% and 0.52% (v/v), respectively. Therefore, 0.37% and 0.52% (v/v) doses were used for the remaining portion of this study. Investigation of the expression and activity levels revealed that CYP1A1-1A2, CYP2E1, and CYP3A4 activities were not affected by ABS significantly, with qPCR and Western blot results corroborating this result.

DISCUSSION

Our study found that the activity, mRNA, and protein expression levels of CYP isozymes did not change with the application of ABS, suggesting that when humans are exposed to ABS, there may not be any risk associated with clinical drug toxicity, cancer formation, and drug metabolism disorders in humans.

Role of dietary polyphenols on gut microbiota, their metabolites and health benefits

The beneficial health roles of dietary polyphenols in preventing oxidative stress related chronic diseases have been subjected to intense investigation over the last two decades. As our understanding of the role of gut microbiota advances our knowledge of the antioxidant and anti-inflammatory functions of polyphenols accumulates, there emerges a need to examine the prebiotic role of dietary polyphenols. This review focused onthe role of different types and sources of dietary polyphenols on the modulation of the gut microbiota, their metabolites and how they impact on host health benefits. Inter-dependence between the gut microbiota and polyphenol metabolites and the vital balance between the two in maintaining the host gut homeostasis were discussed with reference to different types and sources of dietary polyphenols. Similarly, the mechanisms behind the health benefits by various polyphenolic metabolites bio-transformed by gut microbiota were also explained. However, further research should focus on the importance of human trials and profound links of polyphenols-gut microbiota-nerve-brain as they provide the key to unlock the mechanisms behind the observed benefits of dietary polyphenols found in vitro and in vivo studies.