Nature-inspired skin care products are experiencing a significant increase in market trend. The global natural cosmetics market was valued at USD 31.84 billion in 2023 and is projected for continued growth. This shift reflects a “return to nature” trend in the cosmetic industry, partly driven by concerns about potentially harmful synthetic chemicals and their effects on the skin. Natural products are seen as safer, less likely to cause allergies or irritations, and more sustainable for the environment. In this context, food-derived molecules are being explored as ingredients for this emerging market. It is a well-established concept that food, beyond its nutritional value, has beneficial physiological effects on the human body, including skin health. Phytochemical compounds from botanical sources have been recognized for their potent bioactivity and applications in human health. Berries are a popular source of natural bioactive compounds with high phenolic content, such as phenolic acids, anthocyanins, and proanthocyanidins. Berry extracts have consistently shown antibacterial, antioxidant, and anti-inflammatory effects, as well as mechanisms for activating biological responses relevant to skin disorders. Despite the growing interest, there had not been a systematic review specifically addressing the topical effects of berry extracts on skin health. This systematic review aimed to provide an overview of the impact of berry fruit extracts on topical skin care interventions, summarizing published evidence, and highlighting therapeutic potential and limitations.
Key Findings
The systematic review of preclinical murine model studies revealed significant potential for berry fruit extracts in topical applications for skin health:
•Anti-inflammatory and Antioxidant Properties: Studies showed evidence that berries possess anti-inflammatory and antioxidant properties. These effects are attributed to compounds like anthocyanins, cyanidins, polyphenols, and catechins found in berries.
•Reduced Oxidative Stress: Topical berry treatment reduced markers of oxidative stress in skin cells. This included a decrease in malondialdehyde (MDA), carbonylated proteins, nitric oxide, and DNA damage markers such as 8-OHdG and pyrimidine dimers (CPD). Some studies also reported increased activity of antioxidant enzymes like superoxide dismutase, catalase, and glutathione S-transferase (GST).
•Modulated Inflammatory Pathways: Treatment with berries influenced nuclear inflammation pathways. There was a reduction in NF-κB expression, which led to decreased iNOS expression. COX-2 expression was also reduced, and in one study, the MAPK pathway decreased.
•Decreased Pro-inflammatory Cytokines: A decrease was observed in several pro-inflammatory cytokines, most frequently IL-6 and TNF-α. Decreases were also reported for IL-1β, IFN-γ, IL-4, IL-8, and MCP-1.
•Increased Anti-inflammatory Cytokines: An increase was noted in the anti-inflammatory cytokine IL-10.
•Enhanced Extracellular Matrix (ECM): Berry extracts improved ECM components, which are essential for skin integrity. The greatest enhancement was seen in collagen deposition, followed by increases in elastin, fibronectin, and hydroxyproline. A decrease in metalloproteinases (MMP-1, MMP-2), enzymes that degrade collagen, was also observed.
•Reduced Inflammatory Cells: Treatments led to a reduction in various inflammatory cells, including nonspecific inflammatory infiltrates, mast cells, mononuclear cells, and neutrophils.
•Improved Pathological Outcomes: Berry topical treatments positively affected skin health conditions associated with animal wound models. This included increased wound closure. and increased epidermal thickness. Some studies reported a decrease in tumors and improved skin wrinkling. Furthermore, reductions in erythema and edema were observed, along with increased tissue nutrition via angiogenesis. Cellular apoptosis was also reduced.
•Risk of Bias: The analysis showed a low risk of bias regarding animal experiments and treatment applications. However, items like allocation concealment, blinding outcome assessment, selective reporting, and phytochemical characterization had predominantly high risks of bias, often due to insufficient reporting.
This systematic review highlights the significant potential of berry fruit extracts for treating skin diseases and wounds, primarily through their well-established bioactive compounds. The novelty of this research lies in being the first systematic review specifically synthesizing evidence on the topical effects of berry extracts on skin health, focusing on preclinical in vivo studies The findings consistently demonstrated improvements in key indicators of skin health and repair, including enhanced wound healing, increased production of essential extracellular matrix proteins like collagen and elastin, stimulated cellular regeneration, and assistance in angiogenesis. Furthermore, berry extracts showed the ability to modulate oxinflammation pathways, effectively reducing oxidative stress and inflammation markers while increasing anti-inflammatory responses. These results strongly support the potential of berry extracts for topical formulations. The future implications are significant for the pharmaceutical and cosmetic industries, suggesting that berry extract-based topical products could be developed for a range of dermatological applications, such as treating burns, open wounds, psoriasis, and dermatitis. Further research exploring underutilized berry species and better characterization of bioactive compounds in future studies are recommended to fully harness the therapeutic potential of berries for enhancing overall tissue health.
Link to the study: https://www.mdpi.com/2079-9284/12/3/87
