Preapoptotic chromatin changes induced by ultraviolet B irradiation in human erythroleukemia K562 cells.

Apoptosis

Department of Microbial Biotechnology and Cell Biology, University of Debrecen, 1 Egyetem Square, Debrecen 4010, Hungary.

Published: November 2007

Exponentially growing human erythroleukemia K562 cells were permeabilized and the dose dependent decrease of DNA synthesis rate was measured after ultraviolet (UV B, 290 nm) irradiation. Cells were able to overcome 2 and 5 J/m2 UV doses, partial recovery was observed at 15 J/m2, while at high (25 J/m2) UV dose replicative DNA synthesis remained suppressed. K562 cells were subjected to synchronization prior to and after UV irradiation (24 J/m2) and 18 fractions were collected by centrifugal elutriation. Cell cycle analysis by flow cytometry did not show early apoptotic cells after UV irradiation. The gradual increase in DNA content typical for non-irradiated cells was contrasted by an early S phase block between 2.2 and 2.4 C-values after UV irradiation. Cell cycle dependent chromatin changes after ultraviolet irradiation were seen as a fine fibrillary network covering the mainly fibrous chromatin structures and incompletely folded primitive chromosomes. Based on observations after UV irradiation and on earlier results with cadmium treatment and gamma irradiation, we confirm that typical chromatin changes characteristic to genotoxic agents can be recognized and classified.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10495-007-0118-0DOI Listing

Publication Analysis

Top Keywords

chromatin changes
12
k562 cells
12
irradiation
8
ultraviolet irradiation
8
human erythroleukemia
8
erythroleukemia k562
8
dna synthesis
8
cell cycle
8
cells
6
preapoptotic chromatin
4

Similar Publications

Light is an important environmental factor affecting the ripening and quality of strawberry fruit. Previous studies have shown that red light treatment can promote strawberry ripening. Gene expression is closely associated with chromatin openness, and changes in chromatin accessibility are crucial for the binding of transcription factors to downstream regulatory sequences.

View Article and Find Full Text PDF

Male reproductive health is governed by an intricate interplay of genetic, epigenetic, and environmental factors. Epigenetic mechanisms-encompassing DNA methylation, histone modifications, and non-coding RNA activity-are crucial both for spermatogenesis and sperm maturation. However, oxidative stress, driven by excessive reactive oxygen species, disrupts these processes, leading to impaired sperm function and male infertility.

View Article and Find Full Text PDF

Although commonly appreciated for their anti-oxidative and neuroprotective properties, flavonoids can also exhibit pro-oxidative activity, potentially reducing cell survival, particularly in the presence of metal ions. Disrupted copper homeostasis is a known contributor to neuronal dysfunction through oxidative stress induction. This study investigated the effects of myricitrin (1-20 μg/mL) on copper-induced toxicity (0.

View Article and Find Full Text PDF

Background: Vascular cognitive impairment (VCI) is a significant contributor to dementia, yet the precise mechanisms underlying the cognitive decline associated with chronic cerebral hypoperfusion (CCH) remain unclear. This study investigated the molecular and epigenetic changes in the striatum, a brain region critical for motor function and cognition, following chronic hypoperfusion using a bilateral common carotid artery stenosis (BCAS) model in mice.

Methods: RNA-seq was utilized to identify differentially expressed genes (DEGs) associated with hypoperfusion.

View Article and Find Full Text PDF

Epigenetic modulation by oncolytic viruses: Implications for cancer therapeutic efficacy.

Biochim Biophys Acta Rev Cancer

January 2025

Xinyuan Institute of Medicine and Biotechnology, College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou, China. Electronic address:

Among various therapeutic agents, Oncolytic Viruses (OVs) are the most promising anticancer therapeutics because of their tumor-specific targeting and capability to mediate an antitumor immune response. In this review, we will discuss how epigenetic reprogramming of both the host and tumor can facilitate increased sensitivity of tumors to OV therapy. OVs infect tumor cells and modulate epigenetic landscapes, including DNA methylation, histone modifications, and chromatin remodeling, as well as non-coding RNA expression that consequently induces immune responses.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!