Stress-induced fibroblast senescence is thought to contribute to skin aging. Ultraviolet light (UV) radiation is the most potent environmental risk factor in these processes. An Epilobium angustifolium (EA) extract was evaluated for its capacity to reverse the senescent response of normal human dermal fibroblasts (NHDF) in vitro and to exhibit skin photo-protection in vivo. The HPLC-UV-MS analysis of the EA preparation identified three major polyphenol groups: tannins (oenothein B), phenolic acids (gallic and chlorogenic acids) and flavonoids. EA extract increased the cell viability of senescent NHDF induced by serum deprivation. It diminished connective tissue growth factor and fibronectin gene expressions in senescent NHDF. Down-regulation of the UV-induced release of both matrix metalloproteinase-1 and -3 and the tissue inhibitor of matrix metalloproteinases-1 and -2, and also down-regulation of the gene expression of hyaluronidase 2 were observed in repeatedly UV-irradiated NHDF after EA extract treatment. Interestingly, EA extract diminished the down-regulation of sirtuin 1 dampened by UV-irradiation. The application of EA extract using a sub-irritating dose protected skin against UV-induced erythema formation in vivo. In summary, EA extract diminished stress-induced effects on NHDF, particularly on connective tissue growth factor, fibronectin and matrix metalloproteinases. These results collectively suggest that EA extract may possess anti-aging properties and that the EA polyphenols might account for these benefits.
The Maillard reaction and its end products, AGE-s (Advanced Glycation End products) are rightly considered as one of the important mechanisms of post-translational tissue modifications with aging. We studied the effect of two AGE-products prepared by the glycation of lysozyme and of BSA, on the expression profile of a large number of genes potentially involved in the above mentioned effects of AGE-s. The two AGE-products were added to human skin fibroblasts and gene expression profiles investigated using microarrays. Among the large number of genes monitored the expression of 16 genes was modified by each AGE-preparations, half of them only by both of them. Out of these 16 genes, 12 were more strongly affected, again not all the same for both preparations. Both of them upregulated MMP and serpin-expression and downregulated some of the collagen-chain coding genes, as well as the cadherin- and fibronectin genes. The BSA-AGE preparation downregulated 10 of the 12 genes strongly affected, only the serpin-1 and MMP-9 genes were upregulated. The lysozyme-AGE preparation upregulated selectively the genes coding for acid phosphatase (ACP), integrin chain alpha5 (ITGA5) and thrombospondin (THBS) which were unaffected by the BSA-AGE preparation. It was shown previously that the lysozyme-AGE strongly increased the rate of proliferation and also cell death, much more than the BSA-AGE preparation. These differences between these two AGE-preparations tested suggest the possibility of different receptor-mediated transmission pathways activated by these two preparations. Most of the gene-expression modifications are in agreement with biological effects of Maillard products, especially interference with normal tissue structure and increased tissue destruction.
DNA methylation is well-known to be associated with ovarian cancer (OC) and has great potential to serve as a biomarker in monitoring response to therapy and for disease screening. The purpose of this study was to investigate methylation of HNF1B and GATA4 and correlate detected methylation with clinicopathological characteristic of OC patients. The study group consisted of 64 patients with OC and 35 control patients. To determine the most important sites of HNF1B and GATA4, we used next-generation sequencing. For further confirmation of detected methylation of selected regions, we used high-resolution melting analysis and methylation-specific real-time polymerase chain reaction (PCR). Selected regions of HNF1B and GATA4 were completely methylation free in all control samples, whereas methylation-positive pattern was observed in 32.8% (HNF1B) and 45.3% (GATA4) of OC samples. Evaluating both genes together, we were able to detect methylation in 65.6% of OC patients. We observed a statistically significant difference in HNF1B methylation between samples with different stages of OC. We also detected subtype specific methylation in GATA4 and a decrease of methylation in late stages of OC. The combination of unmethylated HNF1B and methylated GATA4 was associated with longer overall survival. In our study, we employed innovative approach of methylation analysis of HNF1B and GATA4 to search for possible epigenetic biomarkers. We confirmed the significance of the HNF1B and GATA4 hypermethylation with emphasis on the need of selecting the most relevant sites for analysis. We suggest selected CpGs to be further examined as a potential positive prognostic factor.
In conclusion, our study showed that there is significantly higher methylation in GATA4 gene in the endometrial cancer group compared with samples of non-neoplastic endometrium. The finding suggests the importance of hypermethylation of this gene in endometrial carcinogenesis and could have implications for future diagnostic and therapeutic strategies for endometrial cancer based on epigenetic changes.
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