Research Article

Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, as well as Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells

Volume: 5 Number: 1 July 15, 2026
EN

Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, as well as Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells

Abstract

Objective: Instant black tea (IBT) is a water-soluble tea that has a number of properties, including antioxidant, antibacterial, antitoxic, antiviral, antimutagenic, anticancer, and anti-inflammatory effects, among others. The aim of this study was to investigate the effects of IBT on paraoxonase 1 (PON1) gene expression and its paraoxonase and lactonase activities, in a hepatoma cell line (HepG2). Material and Methods: PON1 gene expression was determined by RT-PCR. Paraoxonase and lactonase activities were examined using spectrophotometry. These measurements were performed after 24 and 48 hours of treatment in HepG2 cells. Results: Compared to the negative control, 100 μg/mL IBT treatment suppressed PON1 gene expression at 24 hours; 50 μg/mL treatment at 24 hours and 100 μg/mL treatment at 48 hours increased paraoxonase activities; and finally 50 and 100 μg/mL treatments at 48 hours decreased lactonase activities, all of which were statistically significant (p < .05). Conclusion: IBT can modulate PON1 expression and related enzyme activities in hepatocytes, but detailed in vivo studies are required to confirm these findings and elucidate their biological effects.

Keywords

HepG2, Instant black tea, Lactonase, Paraoxonase

Supporting Institution

Karadeniz Technical University Scientific Research Projects Unit

Project Number

13082

Ethical Statement

This study was not conducted on humans or animals. Therefore, ethical committee approval was not deemed necessary.

Thanks

The authors are grateful to Prof. Dr. Ferit Avcu (Cancer and Stem Cell Research Center, GMMS, Ankara, Türkiye) for providing HepG2 cell lines. We are also grateful to Prof. Bradley W. Bolling (Department of Food Science, University of Wisconsin-Madison, Madison, WI, USA) for proof reading.

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APA
Hajızadeh Tekmeh, H., Kural, B., Demir, S., Us Altay, D., Ozer Yaman, S., Kör, S., Örem, A., Turan, İ., & Alasalvar, C. (2026). Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, as well as Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells. Farabi Medical Journal, 5(1). https://doi.org/10.59518/farabimedj.1923984
AMA
1.Hajızadeh Tekmeh H, Kural B, Demir S, et al. Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, as well as Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells. Farabi Medical Journal. 2026;5(1). doi:10.59518/farabimedj.1923984
Chicago
Hajızadeh Tekmeh, Hamed, Birgül Kural, Selim Demir, et al. 2026. “Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, As Well As Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells”. Farabi Medical Journal 5 (1). https://doi.org/10.59518/farabimedj.1923984.
EndNote
Hajızadeh Tekmeh H, Kural B, Demir S, Us Altay D, Ozer Yaman S, Kör S, Örem A, Turan İ, Alasalvar C (July 1, 2026) Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, as well as Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells. Farabi Medical Journal 5 1
IEEE
[1]H. Hajızadeh Tekmeh et al., “Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, as well as Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells”, Farabi Medical Journal, vol. 5, no. 1, July 2026, doi: 10.59518/farabimedj.1923984.
ISNAD
Hajızadeh Tekmeh, Hamed - Kural, Birgül - Demir, Selim - Us Altay, Diler - Ozer Yaman, Serap - Kör, Sevil - Örem, Asım - Turan, İbrahim - Alasalvar, Cesarettin. “Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, As Well As Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells”. Farabi Medical Journal 5/1 (July 1, 2026). https://doi.org/10.59518/farabimedj.1923984.
JAMA
1.Hajızadeh Tekmeh H, Kural B, Demir S, Us Altay D, Ozer Yaman S, Kör S, Örem A, Turan İ, Alasalvar C. Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, as well as Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells. Farabi Medical Journal. 2026;5. doi:10.59518/farabimedj.1923984.
MLA
Hajızadeh Tekmeh, Hamed, et al. “Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, As Well As Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells”. Farabi Medical Journal, vol. 5, no. 1, July 2026, doi:10.59518/farabimedj.1923984.
Vancouver
1.Hamed Hajızadeh Tekmeh, Birgül Kural, Selim Demir, Diler Us Altay, Serap Ozer Yaman, Sevil Kör, Asım Örem, İbrahim Turan, Cesarettin Alasalvar. Evaluation of the Effects of Instant Black Tea on the Gene Expression of PON1, as well as Its Paraoxonase and Lactonase Enzyme Activities, in HepG2 Cells. Farabi Medical Journal. 2026 Jul. 1;5(1). doi:10.59518/farabimedj.1923984