New research suggests that polyfloral honey may help protect human skin cells from age-related damage caused by ultraviolet (UV) radiation. The findings were published in the journal Antioxidants.
Skin cells treated with a diluted honey solution before UV exposure retained more of their youthful characteristics and regenerative capacity than untreated cells. The results support the idea that honey could one day become an ingredient in creams or clinical products designed to slow skin aging.
The study also begins to reveal, gene by gene, how honey helps cells cope with UV-induced stress, Planet Today reports.
Honey is already widely used in medicine. Honey-based dressings and gels are commonly used to treat burns and chronic wounds because of their antimicrobial and anti-inflammatory properties.
The study was led by Fikriye Fulya Kavak, a member of Professor Margherita Maioli's research team at the University of Sassari (UNISS). Kavak noted that certain types of honey, particularly Manuka honey, are already used in medical wound dressings. She wanted to determine whether high-quality polyfloral honey could do more than promote wound healing and also protect living skin cells.
"I believe this is a promising area, especially for applications in skincare and dermocosmetics," Kavak said.
To investigate, the researchers worked with living human skin cells rather than cosmetic formulations. They cultured three different types of human skin cells simultaneously, representing an advance over previous studies that examined only one cell type at a time.
The experiment included skin stem cells obtained from biopsies, fibroblasts, which form the skin's structural framework, and keratinocytes, which make up the outermost layer of the skin. Instead of growing in conventional Petri dishes, the cells were maintained in a bioreactor, where culture fluid continuously circulated through interconnected chambers, more closely mimicking the environment of living skin.
Some cell cultures were pretreated for 48 hours with a 1% honey solution, a concentration previously shown to be safe and mildly stimulatory for cells.
The cells were then exposed to UV radiation using a lamp calibrated to wavelengths associated with skin aging. The lamp was positioned approximately 10 centimeters from the samples and applied for two to three minutes.
Ultraviolet radiation does more than cause sunburn. It damages DNA, increases the production of reactive oxygen species, and drives cells into cellular senescence, a state in which they stop dividing and renewing themselves. In the honey-treated stem cells, researchers observed the opposite pattern.
Genes responsible for maintaining stem cell youthfulness and self-renewal remained more active than in cells exposed only to UV radiation, while genes associated with aging and loss of cellular function were less active.
The team monitored the activity of more than 20 genes involved in skin regeneration, aging, and repair. Rather than influencing a single genetic pathway, honey appeared to modulate many genes simultaneously.
"This supports the idea that polyfloral honey acts as a multi-component biological modulator rather than targeting a single molecular pathway," Kavak explained.
Stem cells treated with honey produced lower levels of nitric oxide, a signaling molecule that increases during cellular damage, while their overall antioxidant defenses became stronger.
Honey's antioxidant properties have been demonstrated previously. In one earlier study, rats fed honey for several months showed less DNA damage and greater activity of antioxidant enzymes than animals that did not receive honey.
Much of the skin's elasticity depends on fibroblasts, which produce collagen and hyaluronic acid, a molecule that helps retain moisture. UV radiation damages these cells, and untreated cultures showed clear signs of deterioration.
The gene responsible for hyaluronic acid production became inactive, while expression of a protective heat shock protein gene—part of the cell's repair machinery—declined. At the same time, a gene involved in programmed cell death became more active.
Honey pretreatment largely reversed these effects. The hyaluronic acid gene became active again, heat shock protein expression recovered, and signals promoting cell death weakened, allowing fibroblasts to return closer to a healthy, unstressed state.
Similar protective effects have been reported by other research groups. In one study, extracts of Greek honey protected human skin cells from UVB radiation, reducing DNA strand breaks and oxidative damage to proteins.
One of the most unexpected findings was the balanced nature of honey's effects.
Cells recovering from damage often activate the Wnt signaling pathway, a major regulator of growth and tissue regeneration. However, honey did not strongly stimulate this pathway. Instead, it appeared to maintain cellular balance by preserving one growth signal essential for stem cell health while preventing excessive activation of a partner protein associated with metabolic stress.
This allowed cells to strengthen their defenses without entering a state of excessive growth or overstimulation.
"What surprised me most was how balanced the response was," Kavak said.
Rather than triggering an aggressive repair response, honey appeared to support the cells' natural protective mechanisms while preventing dysregulation of regenerative signaling.
Not all types of honey performed equally well. In a separate study, researchers tested commercially available Manuka honey on UV-exposed fibroblasts.
In that experiment, Manuka honey disrupted cellular metabolism and produced only modest protection against UV damage, suggesting that the biological effects depend on both the type of honey and the specific cell types being studied.
The researchers emphasize that honey is not a substitute for sunscreen.
"It is important to remember that this is not yet a finished skincare product or a medical treatment," Kavak stressed.
The polyfloral honey used in the study was obtained from beekeepers in eastern Turkey. It contained particularly high levels of plant-derived compounds, including the flavonoid acacetin and several antioxidant acids. Its proline content exceeded the minimum European quality standard by more than fivefold, indicating exceptional purity and quality.
The research team is now investigating whether the observed genetic changes are also reflected at the protein level—the molecules that ultimately perform most cellular functions. They are also developing microscopic honey-containing fibers that could deliver active compounds to the skin in controlled doses.
Under laboratory conditions using living skin cells, a diluted honey solution shifted dozens of genes from an aging profile toward a regenerative one while strengthening the cells' antioxidant defenses. Importantly, this occurred without triggering the uncontrolled cell growth often associated with wound healing.
The next step is to determine whether similar protective effects can be demonstrated in living human skin. If confirmed, polyfloral honey could become a valuable ingredient in future creams and wound dressings designed to protect the skin from sun-induced damage.
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