Picosecond Laser-Induced Optical Breakdown: A Novel Approach to Reversing Photoaging at the Molecular Level

Area of Science:

• Dermatology and Aesthetic Medicine
• Biomedical Engineering
• Molecular Biology

Background:

• Photoaging, caused by UV radiation, presents a significant challenge with limited effective treatments.
• Conventional lasers use thermal mechanisms, often causing side effects.
• Picosecond laser-induced optical breakdown (LIOB) offers a novel photomechanical approach to address UV damage.

Purpose of the Study:

• To comprehensively characterize the molecular mechanisms of photoaging reversal using consecutive 755 nm Alexandrite picosecond laser treatments.
• To evaluate the efficacy of LIOB in reversing established UV-induced skin damage.
• To establish a scientific foundation for the clinical translation of picosecond laser technology.

Main Methods:

• UV irradiation was used to induce photoaging in mice.
• Consecutive picosecond laser treatments (755 nm) were administered.
• Assessments included wrinkle scoring, erythema, transepidermal water loss, collagen evaluation, histology, and molecular analysis.

Main Results:

• Picosecond laser treatments significantly reduced wrinkles and erythema.
• LIOB activated TGF-β/Smad pathways, boosting collagen synthesis and reducing MMP-9.
• Skin barrier function was restored with increased filaggrin and AQP3, while inflammation (NF-κB) decreased.

Conclusions:

• Consecutive LIOB is a paradigm-shifting therapy for photoaging reversal.
• This approach activates coordinated repair pathways without thermal damage.
• The elucidated molecular mechanisms support clinical translation for effective and safe photoaging treatment.