Metformin effect on driving cell survival pathway through inhibition of UVB-induced ROS formation in human keratinocytes

Protective effect of ferulic acid-hyaluronic acid copolymer against UVB irradiation in a human HaCaT cell line

Excessive UVB exposure increased the production of reactive oxygen species (ROS), leading to oxidative damage and epidermal inflammation. To enhance UVB protection effect, a strong phenolic antioxidant, ferulic acid (FA) was designed onto HA via a free radical mediated method. Our previous work has confirmed its structural characterization and in vitro antioxidant. The aim of this study was to evaluate its protective effects against UVB-induced damage in human HaCaT cells. We observed a significant reduction in cell viability to 57.43 % following UVB exposure at a dose of 80 mJ/cm2. However, pretreatment with FA-HA (250 to 2000 μg·mL-1) significantly attenuated cytotoxicity in a dose-dependent manner. Furthermore, FA-HA was found to suppress the intracellular generation of ROS and up-regulated the expression of the antioxidant enzyme superoxide dismutase (SOD). The elevated levels of pro-inflammatory cytokines, including interleukin-1 beta (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-α) as well as the mRNA expression of matrix metalloproteinase-1/9 (MMP-1/9) induced by UVB irradiation, were also effectively reduced by FA-HA. Additionally, FA-HA treatment decreases the phosphorylation of mitogen-activated protein kinase (MAPK) and activator protein-1 (AP-1), ultimately preventing apoptosis. These findings suggest that FA-HA is a promising candidate for UVB protection in skincare formulations.

Analysis of Biogenic Amines and Small Molecule Metabolites in Human Diabetic Wound Ulcer Exudate

Diabetic foot ulcers (DFUs) pose a significant challenge in wound care due to their chronic nature and impaired healing processes. This study examines the biogenic amines and small molecule metabolites present in DFU wound exudates to identify their potential roles in wound healing. Under an IRB-approved protocol, wound fluid samples were collected from 25 diabetic patients and analyzed using ultrahigh-pressure liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry. The analysis identified 721 metabolites, with 402 confirmed through stringent criteria. Key metabolites significantly contributing to the wound exudates include betaine, lactic acid, carnitine, choline, creatine, and metformin (a widely used first-line treatment for type 2 diabetes). These molecules are known to influence wound healing processes, such as collagen synthesis, angiogenesis, inflammation modulation, and energy metabolism. Notably, the presence of drugs such as metformin and beclomethasone in the exudates suggests significant pharmacodynamic interactions that could influence wound healing. Specifically, we discovered that the combined use of insulin and metformin administered systemically significantly increased the concentration of metformin in the wound exudates (from 0.3% ± 0.0 to 3.1% ± 3.4; p = 0.00 49). This study highlights the complexity of DFU exudate composition and underscores the potential for targeted metabolic profiling to develop personalized wound care strategies.

Τhe Endless Beauty of Metformin: Does It Also Protect from Skin Aging? A Narrative Review

Metformin has shown multiple effects beyond its widely known antidiabetic effect. Impressively, it has already been proposed as an anti-aging factor. However, the potentially protective role of metformin in skin aging, the most common manifestation of aging, is not well examined. Existing evidence based on experimental studies suggests a potential anti-aging effect on skin. Proposed molecular skin anti-aging mechanisms of metformin include mainly reduction of nuclear factor kappa B (NF-κB) (p65) activity. Moreover, metformin appears to inhibit ultraviolet B (UVB)-induced secretion of pro-inflammatory cytokines. Nonetheless, data is still limited, and so more studies are needed. Importantly, we need more studies conducted in humans to further examine this interesting potential. Until then, whether oral administration of metformin or local use of the agent could be used to delay skin aging remains to be answered.

Heat Treatment Improves UV Photoprotective Effects of Licorice in Human Dermal Fibroblasts

External stimulation of the skin by ultraviolet B (UVB) radiation induces oxidative stress or inflammation, causing skin aging and skin cancer. Glycyrrhiza uralensis (licorice) has been used as a medicinal plant for its antioxidant, anti-inflammatory, antiviral, antimicrobial, anticarcinogenic, and hepatoprotective properties. The present study analyzed the effects of thermal processing on the bioactivities of licorice. Heat-treated licorice (HL) extracts had better antioxidant and anti-inflammatory activities than non-treated licorice (NL) extract. HL extracts also had higher total phenol contents than NL extract. In particular, contents of isoliquiritigenin, an antioxidant and anti-inflammatory substance of licorice, increased in proportion to the skin-protection effects of HL extracts. Heat treatment increased the contents of phenolic compounds such as isoliquiritigenin in licorice extract, which improved the UV photoprotective effect of licorice in human dermal fibroblasts.