How Antibiotics Trigger Alpha Satellite DNA Overexpression and Epigenetic Changes

Antibiotics May Be Doing More Than You Think: A Hidden Impact on Our DNA

Antibiotics are often hailed as life-saving medicines, fighting off harmful bacteria and infections. But recent research suggests they might be influencing more than just bacterial cells. A groundbreaking study published in Epigenetics & Chromatin reveals that certain antibiotics can trigger overexpression of alpha satellite DNA—a repetitive sequence in human chromosomes—and even cause epigenetic changes affecting genome stability.

This discovery is reshaping how scientists view the broader effects of antibiotics on human health.

What Are Alpha Satellite DNA and Why Do They Matter?

Alpha satellite DNA consists of highly repetitive sequences found in the pericentromeric regions of human chromosomes. Traditionally considered “junk DNA,” these sequences actually play vital roles in:

Chromosome stability
Cell division accuracy
Centromere function

Any disruption in their transcription can potentially lead to genomic instability, a hallmark of aging, cancer, and other diseases.

The Surprising Role of Antibiotics

The study investigated commonly used antibiotics, including geneticin, hygromycin B, and rifampicin, at concentrations frequently applied in laboratories and medical treatments.

Key findings include:

Overexpression of Alpha Satellite DNA
- HeLa cells exposed to geneticin showed almost a 5-fold increase in alpha satellite transcription.
- Rifampicin induced the highest expression in glioblastoma A-1235 cells.
Epigenetic Modifications
- Antibiotic exposure reduced H3K9me3, a repressive histone mark, and increased H3K18ac, associated with active transcription.
- These modifications suggest antibiotics may alter chromatin structure, influencing gene expression far beyond their antibacterial effects.
Cell-Line Specific Responses
- Different cell types responded differently, pointing to cell-specific mechanisms and potential implications for personalized medicine.

Why This Matters: Beyond the Petri Dish

The findings raise critical questions:

Could long-term or high-dose antibiotic use disrupt genome stability in patients?
Might antibiotic-induced epigenetic changes contribute to aging or cancer risk?
How should scientists interpret cell culture experiments involving antibiotics?

While further research is needed, the study warns researchers and clinicians to consider potential off-target effects of antibiotics on human cells.

Looking Ahead

This research highlights the complex interactions between drugs and our genome. Understanding these effects could:

Improve drug safety evaluations
Guide personalized antibiotic treatments
Offer insights into epigenetic regulation and disease prevention

Final Thoughts

Antibiotics are invaluable tools, but this study reminds us they are not without consequences. By uncovering their hidden impact on alpha satellite DNA and epigenetic regulation, scientists are opening the door to safer, more precise medical treatments.

Reference

Ljubić, S., Matulić, M., Đermić, D., Feliciello, M. C., Procino, A., Ugarković, Đ., & Feliciello, I. (2025). Antibiotics induce overexpression of alpha satellite DNA accompanied with epigenetic changes at alpha satellite arrays as well as genome-wide. Epigenetics & Chromatin, 18(1), 62. https://doi.org/10.1186/s13072-025-00628-z