It's been debated whether functional claims for CBD in skin care, such as for soothing, anti-acne and other benefits, hold any water. It's even been suggested that marketers promote products based on the inclusion of CBD or hemp ingredients, rather than anecdotal reports of efficacy. But new evidence from Genemarkers could change this direction.
During the SCC Annual Meeting, held Dec. 17 and 18, 2019, in NYC, Anna Langerveld, Ph.D., of Genemarkers LLC, presented the results of a study performed to correlate gene expression changes in vitro with an ex vivo skin tissue system. According to the researchers, most previous studies have been carried out using monolayer cell cultures with a single cell type, or using consumer-based surveys.
Previous studies using 2D cells have shown changes in biological mechanisms ranging from the regulation of inflammation, via NRF2, NFKB and inflammasome pathways; to melanogenesis, cell proliferation, apoptosis and keratinocyte differentiation. Here, gene expression changes in an in vitro skin model containing keratinocytes and fibroblasts were compared with effects observed in adult human abdominal skin explants.
In vitro: Mircroarray analyses were conducted following the application of 5 mg/mL of CBD isolate at 3 hr, 6 hr, 24 hr and 48 hr. Total changes observed were 54, 84, 537 and 1,253 at these time points, respectively. Researchers noted the genetic expression changes at 24 hr and 48 hr were not only most prominent, but consistent with known CBD functions.
The expression of 49 genes also was shown to change direction over time in response to CBD. Relevant genes included those related to: acne regulation, anti-aging, antioxidant, cell renewal/regeneration, circadian rhythm regulation, epidermal barrier functioning, ECM breakdown and integrity, pain/inflammation/immune response, pigmentation, skin hydration, tissue integrity and wound healing.
See related: [video with update] Confirming CBD Skin Care Claims
Ex vivo: In the skin explants, a comparison was made of 163 genes, measured using a qPCR CBD panel. CBD solutions at 5 mg/mL, 15 mg/mL or 30 mg/mL were applied to the surface of skin cultures and incubated for 24 hr, 48 hr and 72 hr (n = 3), from which RNA was isolated for the qPCR analaysis.
Exposure to CBD was found to regulate the expression of CB1 and CB2 receptors in ex vivo tissues only. As expected, higher concentrations and longer exposures also were required to elicit responses in the skin tissue, versus the in vitro model.
However, 96 similar changes in gene expression were observed in both the in vitro and ex vivo models. Furthermore, ex vivo, while endogenous expression levels of CB1 and CB2 were low, detectable changes occurred in response to the CBD.
Based on these correlations, the researchers concluded gene expression analysis could identify the biological activity and efficacy of CBD. They also proposed such analyses as valuable tools to screen CBD isolates and formulations, ultimately to validate claims.
For more information, contact Genemarkers LLC.