Ongoing research reveals that multifloral honey is a promising candidate for protecting human skin cells from premature ageing and cell damage caused by UV radiation, with the potential for developing future clinical and cosmetic applications.
Honey is already well known in the medical and cosmetic industries for its antioxidant, antimicrobial, anti-inflammatory and wound-healing properties, and sterile honey-derived medical products already exist in the form of dressings, gels and ointments for burns and difficult-to-heal wounds.
"I have always been interested in the fact that certain honeys, such as Manuka honey, are used in medical-grade applications," says Dr Fikiye Fulya Kavak, a member of Prof. Margherita Maioli's research team at the University of Sassari, Italy, whose background in medical biology and personal interests in beekeeping and cosmetic science inspired this project. "This led me to ask whether high-quality multifloral honey could also show measurable protective effects for human skin cells."
Skin is the human body's primary barrier against the environment, but ultraviolet (UV) radiation from the sun significantly accelerates skin ageing and cell stress, which can be a precursor to skin cancer. Prof. Maioli's team wanted to investigate not only whether honey could protect human skin cells from UV damage, promote cell recovery and prevent skin ageing, but they also wanted to find out which molecular and genetic mechanisms might be involved.
For this investigation, the team first grew cultures of the cells that make up human skin, including skin stem cells, fibroblasts and keratinocytes. These were cultured together in a continuously flowing bioreactor system to simulate the physiological environment of human skin.
Before exposing the cultures to UV radiation, some of the cells were treated with 1% multifloral honey for 48 hours. The team then evaluated how the treated and untreated cells responded to UV-induced stress.
The team also analysed the expression of selected genes associated with cellular ageing, stress response and tissue renewal using real-time quantitative PCR. The team were also interested in genes related to stemness (as in stem cell), which is the ability of a cell to differentiate or copy itself.
The major finding was that 1% multifloral honey pretreatment appeared to support a protective and regulatory response against UV-induced stress in both skin stem cells and fibroblasts. "In skin stem cells, honey increased the expression of stemness-related markers, while reducing the expression of aging-associated genes," says Dr Kavak.
In these cells, honey treatment also reduced nitric oxide release and increased antioxidant capacity, suggesting that it may help support antioxidant defences under UV-induced stress conditions.
From the team's genetic analysis, they discovered that the honey treatment helped to regulate cell proliferation and renewal signals and increased expression of cell stress protection genes.
"What was particularly interesting was that honey seemed to help the cells find a healthier balance after UV stress," says Dr Kavak. "Rather than pushing the cells into an exaggerated repair response, it appeared to support protective mechanisms while keeping renewal-related signals under control."
The team's research is still ongoing, and they are further exploring the molecular mechanisms at work. "We have been working on protein-level validation studies to confirm whether the molecular changes observed at the mRNA level are also reflected at the protein level," says Dr Kavak.
There are promising applications for these findings in the medical and cosmetic fields, but the team emphasises that multifloral honey should not yet be considered a clinical application or as an alternative to sunscreen. "Our study was performed in cell-based experimental models, not in humans, so further laboratory, preclinical, and clinical studies are needed before any practical recommendation can be made," says Dr Kavak.
This knowledge could contribute to the development of new cosmetic or clinical skin formulations, especially if the active properties of honey can be delivered in a controlled and biocompatible way, such as through a nanofiber-based system that the team are currently developing.
"These nanofibers have already been characterised, and their biological evaluation is currently ongoing," says Dr Kavak. "This represents an important next step, as nanofiber-based systems may provide a more advanced platform for studying the potential skin-related applications of natural bioactive compounds such as multifloral honey."
