β-ESTRADIOL INDUCES CYTOTOXIC EFFECTS TO HUMAN T-LYMPHOMA (JURKAT) CELLS THROUGH OXIDATIVE STRESS

Abstract

β-estradiol is the most potent estrogen of a group of endogenous estrogen steroids which includes estrone and estriol. This steroid hormone is the most potent natural estrogen, produced mainly by the ovary, placenta, and in smaller amounts by the adrenal cortex, and the male testes. Although β-estradiol protects the renal and cardiovascular systems, the mechanisms involved remain unclear. In this research, we performed the MTT [3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay to evaluate the effect of β-estradiol on human T-lymphoma (Jurkat) cells upon 24 and 48 hours, respectively. Lipid peroxidation assay was also performed to estimate the levels of malondialdehyde (MDA) production in β-estradiol-treated cells. The results of MTT assay demonstrated that low, physiological levels of β-estradiol induce cellular proliferation in Jurkat T-cells. At higher dose of exposure, β-estradiol decreases the viability of Jurkat T-cells compared to the control cells. Data generated from lipid peroxidation assay resulted in a significant increase (p < 0.05) in MDA production in β-estradiol treated sample. Upon 48 h of exposure, MDA concentrations in the sample [µM] (mean ±SE, n = 3) compared to untreated control were 4.9 ± 1.7, 8.1 ± 1,6 11.5 ± 2.2, 21.1 ± 2.3, 19.5 ± 1.4, and 21.5 ± 2.6 in 0, 1, 2, 4, 8, and 16 µM β-estradiol, respectively. In summary, findings from this study demonstrated that high dose of β-estradiol is cytotoxic to Jurkat T-cells. This cytotoxicity is found to be associated with oxidative stress.

Keywords: Jurkat T-cells; Lipid peroxidation assay; MTT assay; β-estradiol.

Figure 1

Schematic representation of the steps in Lipid Peroxidation assay

Figure 2

β-estradiol potently induces toxicity to human T-lymphoma (Jurkat) cells. Jurkat T-cells were treated for 24 and 48 hours with medium supplemented with solvent and various doses (1–16 µM) of β-estradiol.

Figure 3

MDA standard curve showing the net absorbance at 586 nm as a function of MDA concentration.

Figure 4

β-estradiol-induced oxidative stress in human T-lymphoma (Jurkat) cells. Cells were incubated for 48 hours with increasing doses of β-estradiol (1, 2, 4, 8, and 16 µM). Malondialdehyde (MDA) concentrations were determined as described in Materials and Methods. *Significantly different from the control by ANOVA Dunnett's test; P < 0.05. Data are representative of 3 independent experiments.