Ultraviolet (UV) irradiation induces detrimental changes in human skin which result in photoaging. UV-induced intracellular changes cause degradation of extracellular matrix (ECM). UV-stimulated cleavage of collagen in ECM occurs via matrix metalloproteinases (MMPs). (±)-syringaresinol (SYR), a phytochemical which belongs to the lignan group of polyphenols, was investigated for its ability to reverse the UVA-induced changes in human HaCaT keratinocytes and dermal fibroblasts (HDFs) in vitro. Effect of SYR on UVA-induced changes was investigated by production and activation of MMPs and its transcriptional upstream effectors; mitogen-activated protein kinases (MAPKs) and pro-inflammatory mediators. Levels of expression were determined using ELISA, RT-PCR and immunoblotting. UVA irradiation stimulated the production of MMP-1 and inhibited collagen production. SYR treatment suppressed MMP-1 and enhanced collagen production in UVA-irradiated HaCaT keratinocytes and HDFs. SYR repressed the UV-induced phosphorylation of p38, ERK and JNK MAPKs in HaCaT keratinocytes while only suppressing JNK phosphorylation in HDFs. In addition, SYR was able to inhibit UVA-induced production of inflammatory cytokines; TNF-α, COX-2, IL-1β and IL-6. Moreover, SYR suppressed the activator protein-1 (AP-1), a heterodimer of phosphorylated transcription factors c-Jun and c-Fos. SYR-treatment decreased nuclear levels of activated c-Fos and c-Jun as a mechanism to inhibit UVA-induced transcriptional activities leading to MMP-1 production. In conclusion, current results demonstrated that SYR could inhibit UVA-induced upregulation of MMP-1 by suppressing MAPK/AP-1 signaling in HaCaT keratinocytes and HDFs. Therefore, SYR was suggested as a potential compound with antiphotoaging properties against UVA-induced skin aging.
Artemisia princeps, the Korean mugwort, is an edible plant that has various beneficial effects on health, and which has been used as a part of traditional folk medicine. The current study investigated the possible effects of solvent (H2O, n-BuOH, 85% aq. MeOH, and n-hexane) partitioned fractions of A. princeps crude extract (APE) on adipogenic differentiation of 3T3-L1 mouse pre-adipocytes. Characteristics of the differentiated adipocytes were evaluated by Oil red O staining of intracellular lipid droplets, analyzing mRNA and protein levels of peroxisome proliferator-activated receptor (PPAR) γ, CCAAT/enhancer-binding protein (C/EBP) α, and sterol regulatory element-binding protein (SREBP)-1c, and immunoblotting of phosphorylated mitogen-activated protein kinase (MAPK) pathway proteins such as p38, extracellular-signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Introduction of APE fractions to differentiating adipocytes resulted in lowered lipid accumulation and downregulation of the PPARγ pathway. APE fractions significantly decreased mRNA and protein expression of PPARγ, C/EBPα, and SREBP-1c. Analysis of MAPK pathway activation showed similar results since treatment with the APE fraction treatment decreased levels of phosphorylated p38, ERK, and JNK. Overall, the n-BuOH and n-hexane fractions were observed to be the most active fractions to suppress adipogenesis-related signaling in 3T3-L1 cells. The promising ability of APE fractions to inhibit adipocyte differentiation of 3T3-L1 cells suggest that A. princeps has potential to be utilized as a source of anti-obesity compounds.
Preserved scleral graft with AMT was simple, fast, and effective. It was particularly advantageous when large scleral defects or conjunctival scarring was present. With these therapeutic results, preserved scleral graft with AMT qualifies as a new treatment alternative for scleromalacia.
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