Related Experiment Video
Updated: Aug 5, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Eumelanin causes DNA strand breaks and kills cells
Pigment Cell Research
|January 1, 1987
Summary
Synthetic melanin induces DNA strand breaks and toxicity in melanoma cells. This damage can be repaired, though less effectively if melanin remains present.
Area of Science:
- Biochemistry
- Molecular Biology
- Toxicology
Background:
- Eumelanin, a natural pigment, has potential biological roles.
- The interaction of synthetic eumelanin with cellular DNA requires further investigation.
Purpose of the Study:
- To investigate the effects of synthetic eumelanin on DNA integrity in mouse melanoma cells.
- To determine the conditions and factors influencing melanin-induced DNA damage and cellular response.
Main Methods:
- B16CL4 mouse melanoma cells were exposed to synthetic eumelanin.
- DNA strand breaks were quantified using alkaline elution.
- Cell viability and DNA repair mechanisms were assessed under various conditions.
Main Results:
- Synthetic eumelanin caused DNA strand breaks and cytotoxicity in a dose-dependent manner.
- Melanin-induced DNA damage was maximal after 15-20 minutes incubation at 37°C.
- DNA repair occurred even with continued melanin presence, but was faster upon melanin removal.
- Melanin's physical form (e.g., sonication) significantly affected its DNA-damaging activity.
Conclusions:
- Synthetic eumelanin directly damages cellular DNA, leading to toxicity.
- Melanin-induced DNA damage is influenced by incubation time, temperature, concentration, and physical state.
- Cells possess repair mechanisms for melanin-induced DNA damage, with varying efficiency.
Related Concept Videos
01:08Nucleotide Excision Repair
Overview
01:39Mutations
Overview
01:08Nucleotide Excision Repair
Overview
01:35Mutations
Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental factors. Mutations can be characterized in a number of different ways: whether and how they alter the amino acid sequence of the protein, whether they occur over a small or large area of DNA, and whether they occur in somatic cells or germline cells.
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
01:38Nucleotide Excision Repair
DNA Distortion and Damage
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
Cells are regularly exposed to mutagens—factors in the environment that can damage DNA and generate mutations. UV radiation is one of the most common mutagens and is estimated to introduce a significant number of changes in DNA. These include bends or kinks in the structure, which can block DNA replication or transcription. If these errors are not fixed, the damage can cause mutations, which in turn can result in cancer or disease depending on which sequences are...
01:19Pigmentation
The color of the skin is influenced by a number of pigments, including melanin, carotene, and hemoglobin. Recall that melanin is produced by cells called melanocytes, which are found scattered throughout the stratum basale of the epidermis. The melanin is transferred to the keratinocytes via melanosomes.
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...
Melanin occurs in two primary forms: eumelanin that provides black and brown pigment and pheomelanin that provides red color. Dark-skinned individuals produce more melanin than those with pale...