Research Advances on the Use of Biomimetic Marine Adhesive Protein Coating for Skin Photoaging Prevention

Skin photoaging is a significant global health issue, particularly for individuals exposed to prolonged ultraviolet (UV) radiation in outdoor environments. Its manifestations include a reduction in collagen, increased wrinkles, loss of skin elasticity, structural weakening, and associated complications. These physiological changes not only affect an individual’s appearance but also increase the risk of related comorbidities. Despite the use of sunscreens, topical medications (e.g., tretinoins), and antioxidants in daily life, there currently exists no highly effective and long-lasting strategy for the prevention and treatment of skin photoaging.

In response to these challenges, this study focuses on an innovative biomimetic marine adhesive protein coating and investigates its potential in treating skin photoaging. Conducted by Dr. Bo Xue and his research team from the College of Marine Life Science, Ocean University of China, this work was published in Advanced Healthcare Materials in 2025 (DOI: 10.1002/adhm.202402019).

Background and Research Significance

Marine biology, particularly the study of marine adhesive proteins, has long been of critical importance in the field of biomedical materials. Proteins derived from marine sources exhibit excellent properties such as wet adhesion and biological activity, including antioxidant capabilities and extracellular matrix (ECM)-like structural mimicry. These properties make them highly suitable for applications in wound repair and tissue regeneration. However, achieving long-term adhesion of coatings in aquatic environments along with effective functionality remains a challenging task.

This study developed an innovative coating using a natural recombinant protein, SBP9𝚫, extracted from scallop byssal proteins. The main objective of the research was to explore the repair mechanism, effects on cellular behavior, and overall therapeutic potential of this coating for preventing ultraviolet B (UVB)-induced skin photoaging.

Overview of the Research Workflow

The research consisted of the following main steps:

1. Preparation and Characterization of the Coating

The recombinant SBP9𝚫 protein, expressed in Escherichia coli, has a molecular weight of approximately 19 kDa. Using a rapid phase separation process combined with divalent calcium (Ca2+) ion crosslinking, the SBP9𝚫 protein was formed into a uniform and dense coating on glass substrates. Coomassie Brilliant Blue staining, optical microscopy, and atomic force microscopy (AFM) were employed for morphological characterization. The results revealed that the SBP9𝚫 coating exhibited a porous three-dimensional structure, with a particle size of roughly 20 nanometers and a thickness of about 2 micrometers. This structure showed promising potential in applications involving cellular adhesion and spreading.

2. Biocompatibility Testing of the Coating

Good biocompatibility is a fundamental requirement for tissue repair coatings. In vitro experiments using epidermal HaCaT cells, fibroblast L929 cells, and vascular endothelial HUVEC cells were conducted, employing live/dead staining and MTT viability assays to evaluate the safety of the coating. The results demonstrated no significant apoptosis or cytotoxicity after 72 hours of incubation. In fact, the viability and survival rates of L929 cells significantly increased in the presence of the SBP9𝚫 coating. In vivo experiments in mice also showed no abnormal inflammatory cell infiltration after 14 days of continuous skin wound application, and no pathological changes were observed in major organs up to 60 days post-application.

3. The SBP9𝚫 Coating’s Ability to Promote Cellular Behavior

The coating significantly enhanced cellular behaviors related to skin tissue repair, including adhesion, spreading, proliferation, and migration. In vitro experiments demonstrated that surfaces modified with the SBP9𝚫 coating greatly enhanced the adhesion rate and spreading area of HaCaT cells compared to control and poly-L-lysine (PLL)-treated surfaces. Additionally, qRT-PCR analysis revealed significantly increased expression of adhesion-related genes, such as integrin β1 and vinculin. The SBP9𝚫 coating also promoted the proportion of Ki67-positive cells and the mRNA levels of growth factors like EGF, VEGF, and TGF-β1, further confirming its impact on cell proliferation.

4. Antioxidant and Anti-Apoptotic Effects of the Coating

The coating reduced intracellular reactive oxygen species (ROS) accumulation under H2O2-induced oxidative stress, as confirmed by live cell staining and ROS activity assays. Moreover, compared to control groups, the SBP9𝚫 coating significantly downregulated the mRNA expression of apoptosis-related proteins such as Caspase-3 and Caspase-9. Additionally, it increased intracellular levels of antioxidants like glutathione (GSH) and superoxide dismutase (SOD) while decreasing malondialdehyde (MDA) levels, further demonstrating its antioxidant and protective effects in cellular environments.

5. In Vivo Anti-UV Experiments

To validate the practical applicability of the SBP9𝚫 coating, the study developed a UVB-induced skin photoaging mouse model. Results showed that the SBP9𝚫 coating effectively protected the skin from UVB-induced oxidative damage, reducing epidermal thickening, preventing collagen loss, and restoring normal collagen distribution. The coating-treated groups also exhibited significant increases in SOD and GSH levels while showing reduced MDA production in mouse skin. These findings underscore the coating’s antioxidative and tissue-protective properties in vivo.

Research Conclusions and Value

This study highlighted multiple advantages of the SBP9𝚫 coating as a biomimetic material:

1. Enhancing Cellular Behaviors: The SBP9𝚫 coating promotes cell adhesion, spreading, proliferation, and migration, providing an optimal microenvironment for tissue repair-related cells.
2. Antioxidant and Anti-Apoptotic Effects: The coating effectively scavenges ROS and mitigates oxidative stress-induced apoptosis, protecting essential ECM proteins from damage.
3. Practical Application in Photoaging Prevention: The SBP9𝚫 coating demonstrated superior protection under UVB exposure, offering a renewable “wet adhesion” solution for skin protection.

Study Highlights

1. Innovative coating design for skin photoaging prevention.
2. Harnessing the beneficial properties of marine proteins with functionalized self-assembly capabilities to propose a potential solution.
3. Safe, biocompatible, and promising for a wide range of applications.

The development of the SBP9𝚫 coating points to significant advances in addressing the challenges of skin photoaging. It also provides new directions for future research into broader tissue regeneration applications. The potential commercial and medical value of this innovative biomaterial is substantial.