Ten-Eleven Translocation 1 and 2 Enzymes Affect Human Skin Fibroblasts in an Age-Related Manner.

Ten-eleven translocation (TET) enzymes catalyze the oxidation of 5-methylcytosine (5mC), first to 5-hydroxymethylcytosine (5hmC), then to 5-formylcytosine (5fC), and finally to 5-carboxycytosine (5caC). Evidence suggests that changes in TET expression may impact cell function and the phenotype of aging. Proliferation, apoptosis, markers of autophagy and double-strand DNA break repair, and the expression of Fibulin 5 were assessed by flow cytometry in TET1 and TET2-overexpressing fibroblasts isolated from sun-unexposed skin of young (23-35 years) and age-advanced (75-94 years) individuals. In cells derived from young individuals, TET1 overexpression resulted in the inhibition of proliferation and apoptosis by 37% (p = 0.03) and 24% (p = 0.05), respectively, while the overexpression of TET2 caused a decrease in proliferation by 46% (p = 0.01). Notably, in cells obtained from age-advanced individuals, TETs exhibited different effects. Specifically, TET1 inhibited proliferation and expression of autophagy marker Beclin 1 by 45% (p = 0.05) and 28% (p = 0.048), respectively, while increasing the level of γH2AX, a marker of double-strand DNA breaks necessary for initiating the repair process, by 19% (p = 0.04). TET2 inhibited proliferation by 64% (p = 0.053) and increased the level of γH2AX and Fibulin 5 by 46% (p = 0.007) and 29% (p = 0.04), respectively. These patterns of TET1 and TET2 effects suggest their involvement in regulating various fibroblast functions and that some of their biological actions depend on the donor's age.

The chameleon effect in customer relationship management: Experiments on the spillover effects of mimicry in natural settings of a chain hotel and a chain grocery shop.

Numerous experiments have proven that mimicry is highly beneficial (mainly to the mimicker but also to the mimickee). Some studies have shown initial data suggesting the potential of applying this knowledge to business settings. In the present paper we unpack this issue in two ways. First, by presenting potential benefits stemming from mimicry for the mimicking dyad, and second for the business environment represented by the mimicker. Two consecutive studies: a Pretest and a Main Experiment run in natural settings showed great potential in improving the assessments of quality of service provided by verbally mimicking (or not). The results of both studies showed that mimicry offers benefits for the mimicker (increased employee kindness and employee evaluation), and also spillover to the organization/company represented by the mimicking employee (increased opinion of and willingness to return to the shop/hotel). Future research directions and limitations are discussed.

Alterations in the Genomic Distribution of 5hmC in In Vivo Aged Human Skin Fibroblasts.

5-Hydroxymethylcytosine (5hmC) is a functionally active epigenetic modification. We analyzed whether changes in DNA 5-hydroxymethylation are an element of age-related epigenetic drift. We tested primary fibroblast cultures originating from individuals aged 22-35 years and 74-94 years. Global quantities of methylation-related DNA modifications were estimated by the dot blot and colorimetric methods. Regions of the genome differentially hydroxymethylated with age (DHMRs) were identified by hMeDIP-seq and the MEDIPS and DiffBind algorithms. Global levels of DNA modifications were not associated with age. We identified numerous DHMRs that were enriched within introns and intergenic regions and most commonly associated with the H3K4me1 histone mark, promoter-flanking regions, and CCCTC-binding factor (CTCF) binding sites. However, only seven DHMRs were identified by both algorithms and all of their settings. Among them, hypo-hydroxymethylated DHMR in the intron of Rab Escort Protein 1 (CHM) coexisted with increased expression in old cells, while increased 5-hydroxymethylation in the bodies of Arginine and Serine Rich Protein 1 (RSRP1) and Mitochondrial Poly(A) Polymerase (MTPAP) did not change their expression. These age-related differences were not associated with changes in the expression of any of the ten-eleven translocation (TET) enzymes or their activity. In conclusion, the distribution of 5hmC in DNA of in vivo aged human fibroblasts underwent age-associated modifications. The identified DHMRs are, likely, marker changes.

Alterations in 5hmC level and genomic distribution in aging-related epigenetic drift in human adipose stem cells.

Aim: To clarify mechanisms affecting the level and distribution of 5-hydroxymethylcytosine (5hmC) during aging. Materials & methods: We examined levels and genomic distribution of 5hmC along with the expression of ten-eleven translocation methylcytosine dioxygenases (TETs) in adipose stem cells in young and age-advanced individuals. Results: 5hmC levels were higher in adipose stem cells of age-advanced than young individuals (p = 0.0003), but were not associated with age-related changes in expression of TETs. 5hmC levels correlated with population doubling time (r = 0.62; p = 0.01). We identified 58 differentially hydroxymethylated regions. Hypo-hydroxymethylated differentially hydroxymethylated regions were approximately twofold enriched in CCCTC-binding factor binding sites. Conclusion: Accumulation of 5hmC in aged cells can result from inefficient active demethylation due to altered TETs activity and reduced passive demethylation due to slower proliferation.

The effect of wool hydrolysates on squamous cell carcinoma cells in vitro. Possible implications for cancer treatment.

Squamous cell carcinoma of the skin is the second most common cutaneous malignancy. Despite various available treatment methods and advances in noninvasive diagnostic techniques, the incidence of metastatic cutaneous squamous cell carcinoma is rising. Deficiency in effective preventive or treatment methods of transformed keratinocytes leads to necessity of searching for new anticancer agents. The present study aims to evaluate the possibility of using wool hydrolysates as such agents. Commercially available compounds such as 5-fluorouracil, ingenol mebutate, diclofenac sodium salt were also used in this study. The process of wool degradation was based on chemical pre-activation and enzymatic digestion of wool. The effect of mentioned compounds on cell viability of squamous carcinoma cell line and healthy keratinocytes was evaluated. The obtained data show a significantly stronger effect of selected wool hydrolysates compared to commercial compounds (p<0.05) on viability of cells. The wool hydrolysates decreased squamous cell carcinoma cells viability by up to 67% comparing to untreated cells. These results indicate bioactive properties of wool hydrolysates, which affect the viability of squamous carcinoma cells and decrease their number. We hypothesize that these agents may be used topically for treatment of transformed keratinocytes in actinic keratosis and invasive squamous skin cancer in humans.

miR-34a and miR-9 are overexpressed and SIRT genes are downregulated in peripheral blood mononuclear cells of aging humans.

Increased expression of sirtuins lowers the risk of age-related diseases, while their role in the regulation of longevity is not firmly established. Since aging is associated with immunosenescence, we tested whether sirtuin expression was modified in peripheral blood mononuclear cells (PBMC) in an age-related manner and whether this might result from altered expression of the selected miRNAs. The expression of seven SIRT genes and of SIRT1 mRNA-interacting miR-9, miR-34a, miR-132, and miR-199a-5p was evaluated by real-time PCR in PBMC originating from young (Y, n = 57, mean age 27 ± 4.3 years), elderly (E, n = 52, 65 ± 3.4 years), and long-lived (L, n = 56, 94 ± 3.5 years) individuals. Older age was associated with a decreased expression of the majority of the SIRT genes. Most severely affected were median expressions of SIRT1 ( P = 0.000001 for the whole studied group, Y vs. E: P < 0.000001, Y vs. L: P < 0.000001), and of SIRT3 ( P = 0.000001, Y vs. E: P = 0.000004, Y vs. L: P = 0.000028). Older age was also associated with the increased median expression of miR-34a ( P = 0.000001, Y vs. E: P = 0.001, Y vs. L: P = 0.000004) and of miR-9 ( P = 0.05, Y vs. L: P = 0.054). In functional studies, miR-9 interacted with the 3'UTR of SIRT1 mRNA. The SIRT1 mRNA level negatively correlated with the expression of miR-34a ( r = -0.234, P = 0.003). In conclusion, age-related decrease of SIRT1 expression in PBMC might in part result from overexpression of miR-34a and miR-9. In addition, the sustained expression of the SIRT genes in PBMC is not a prerequisite to longevity in humans but might be one of the reasons for the immune system dysfunction in the elderly. Impact statement High expression of sirtuins, particularly SIRT1, lowers the risk of age-related diseases and probably slows down the rate of aging; therefore, their sustained expression should be one of the features of longevity. However, in this work we show that in peripheral blood mononuclear cells (PBMC) of long-lived individuals, expression of majority of the SIRT genes is significantly lower than in cells of young study subjects. In long-lived individuals, downregulation of SIRT1 coexists with upregulation of SIRT1 mRNA-interacting miR-34a and miR-9, indicating the role of epigenetic drift in age-dependent deregulation of SIRT1 expression. Such constellation of SIRT1, miR-34a, and miR-9 expression in PBMC of successfully aging long-lived individuals indicates that, at least in these individuals, it is not a risk factor for morbidity and mortality. It might however affect the function of the immune system and, therefore, aging individuals can profit from interventions increasing the level of SIRT1.

Lack of in vitro effect of aglepristone on IFN-γ and IL-4 production by resting and mitogen-activated T cells of luteal bitches.

BACKGROUND: Aglepristone (RU534) is an antiprogestin used for pregnancy termination, parturition induction and conservative pyometra treatment in bitches. Its molecular structure is similar to mifepristone, an antiprogestin used in human medicine. Mifepristone has been shown to suppress proliferation and cytokine production by T cells, whereas the effect of aglepristone on T cell function remains elusive. The purpose of this project was to investigate the in vitro influence of RU534 on IFN-γ and IL-4 synthesis by peripheral blood T cells isolated from healthy bitches (N = 16) in luteal phase. The peripheral blood mononuclear cells (PBMCs) were incubated with three different dosages of aglepristone, or dimethyl sulfoxide (DMSO), with or without mitogen. The production of cytokines by resting or mitogen-activated T cells was determined by intercellular staining and flow cytometry analysis or ELISA assay, respectively. RESULTS: Our results showed no statistically significant differences in the percentage of IFN-γ and IL-4-synthesizing CD4+ or CD8+ resting T cells between untreated and aglepristone-treated cells at 24 and 48 hours post treatment. Moreover, mitogen-activated PBMCs treated with RU534 displayed similar concentration of IFN-γ and IL-4 in culture supernatants to those observed in mitogen-activated DMSO-treated PBMCs. Presented results indicate that administration of aglepristone for 48 hours has no influence on IFN-γ and IL-4 synthesis by resting and mitogen-activated T cells isolated from diestral bitches. CONCLUSIONS: We conclude that antiprogestins may differentially affect T cell function depending on the animal species in which they are applied.