Cannabidiol (CBD) reduced inflammation caused by ultraviolet B (UVB) radiation in human skin cells and mice, according to new research published in The Journal of Immunology.

The study was conducted by researchers affiliated with the University of Seoul and Seoul National University College of Medicine.

Researchers examined CBD’s effects on human keratinocytes, the primary type of cell found in the outermost layer of the skin. Exposure to UVB radiation substantially increased production of interleukin-6 (IL-6), a signaling protein associated with inflammation.

CBD treatment significantly reduced IL-6 production at both the genetic and protein levels. The researchers found that CBD also suppressed activation of STAT3 and c-Jun, two proteins involved in regulating inflammatory responses.

According to the researchers, the findings indicate that CBD may reduce UVB-induced skin inflammation by interfering with the STAT3–c-Jun signaling pathway.

The team also tested a topical CBD formulation made with a silicone polymer, designed to address CBD’s poor stability and low bioavailability. CBD can degrade when exposed to light or oxygen, potentially limiting its effectiveness in topical products.

The formulation was applied to the backs of hairless mice exposed to UVB radiation. Researchers evaluated epidermal thickness and other signs of inflammatory skin damage to determine whether the delivery system improved CBD’s local effects.

The researchers concluded that CBD reduced UVB-induced inflammation and that silicone polymer-based delivery may offer a way to improve the stability and effectiveness of topical CBD treatments for inflammatory skin conditions caused by UVB exposure.