Project description:The skin is a protective barrier against external insults and any lesion must be rapidly and efficiently repaired. Dermal fibroblasts are the major source of extracellular connective tissue matrix and play an important role in wound healing. Vitamin C is an important water-soluble free radical scavenger and an essential cofactor for collagen synthesis by dermal fibroblasts and, consequently, may contribute to the maintenance of healthy skin. Using microarray analysis, we investigated the effects of long-term exposure to a stable vitamin C derivative, ascorbic acid 2-phosphate (AA2P), in contact-inhibited populations of primary human dermal fibroblasts. Compared with scorbutic cells, cells exposed to AA2P increased the expression of genes associated with DNA replication and repair and with the G(2)/M phase of the cell cycle. Consistent with the gene expression changes, AA2P increased the mitogenic stimulation of quiescent fibroblasts by serum factors and cell motility in the context of wound healing. Furthermore, AA2P-treated fibroblasts showed faster repair of oxidatively damaged DNA bases. We propose that vitamin C may protect the skin by promoting fibroblast proliferation, migration, and replication-associated base excision repair of potentially mutagenic DNA lesions, and we discuss the putative involvement of hypoxia-inducible transcription factor-1 and collagen receptor-related signaling pathways. Experiment Overall Design: Gene expression changes in response to vitamin C were analysed by Microarray technology in GM5659 human skin fibroblasts. Cells were treated with 100 µM of AA or AA2P (or growth medium alone) added fresh every day for a period of 5 days before the vitamin C-induced gene expression changes were investigated. Control, AA- and AA2P-treated samples were collected from three independent experiments each.
Project description:The skin is a protective barrier against external insults and any lesion must be rapidly and efficiently repaired. Dermal fibroblasts are the major source of extracellular connective tissue matrix and play an important role in wound healing. Vitamin C is an important water-soluble free radical scavenger and an essential cofactor for collagen synthesis by dermal fibroblasts and, consequently, may contribute to the maintenance of healthy skin. Using microarray analysis, we investigated the effects of long-term exposure to a stable vitamin C derivative, ascorbic acid 2-phosphate (AA2P), in contact-inhibited populations of primary human dermal fibroblasts. Compared with "scorbutic" cells, cells exposed to AA2P increased the expression of genes associated with DNA replication and repair and with the G(2)/M phase of the cell cycle. Consistent with the gene expression changes, AA2P increased the mitogenic stimulation of quiescent fibroblasts by serum factors and cell motility in the context of wound healing. Furthermore, AA2P-treated fibroblasts showed faster repair of oxidatively damaged DNA bases. We propose that vitamin C may protect the skin by promoting fibroblast proliferation, migration, and replication-associated base excision repair of potentially mutagenic DNA lesions, and we discuss the putative involvement of hypoxia-inducible transcription factor-1 and collagen receptor-related signaling pathways.
Project description:The skin is the human body’s largest organ and is in contact with a diverse community of microorganisms that includes both resident and pathogenic bacteria. Skin immune defenses include the production of antimicrobial proteins that kill bacteria directly. However, we still have an incomplete understanding of how skin antimicrobial proteins promote homeostasis with resident bacterial communities and limit infection. Here, we show that resistin-like molecule α (RELMα) is an antibacterial protein that is produced by keratinocytes and sebocytes in the mouse skin. RELMα expression was induced in mouse skin by resident and pathogenic skin bacteria and was bactericidal for several bacterial species found on the skin, including Streptococcus pyogenes. Mice lacking RELMα had altered resident skin bacterial communities and were more susceptible to bacterial infection, indicating that RELMα controls bacterial colonization of the skin. RELMα expression required dietary vitamin A and could be induced by therapeutic retinoids that protected against bacterial infection in a RELMα-dependent manner. Resistin, another member of the RELM family, was expressed in human skin, required retinoids for expression, and killed skin bacteria, indicating a conserved function for RELM proteins in skin innate immunity. Our findings thus identify members of the RELM family as antibacterial proteins that provide vitamin A-dependent antimicrobial protection of the skin, and provide insight into why skin immunity requires adequate dietary vitamin A.
Project description:To investigate the mechanism of radiation induced bystander effect, we explored miRNAs expression in supernatant of human skin fibroblasts after culturing for 24h post UV irradiation. Primary human skin fibroblasts were obtained from healthy volunteers by means of a foreskin circumcision. Human skin fibroblasts was irradiated with 20J/cm2 UVA or 60mJ/cm2 UVB. Expression of miRNAs were tested by microarray between radiation and control samples.
Project description:Human skin fibroblasts from an individual with hereditary vitamin D-resistant rickets bearing a homozygous p.Arg30* VDR mutation [Damiani et al., Osteoporos Int 2015; 26(6):1819-23] and from an age/sex-matched control were obtained from 4-mm punch biopsies of the forearm skin, after institutional board approval and with informed consent. Skin explants were fragmented in 6-well tissue culture plates and covered in complete AmnioMAX™ C-100 medium until attachment to surface; after approximately 12 days fibroblasts grown out of explants covered well surfaces completely. Secondary fibroblast cultures were maintained in high glucose DMEM supplemented with 10% FBS and 1% P/S. Fibroblasts were used for experiments between passages five to fifteen. Global gene expression of CO and MUT fibroblasts in response to 1,25D or ethanol vehicle (Veh) was analysed using microarrays. Six independent biological replicates were performed for each experimental condition: CO Veh, CO 1,25D, MUT Veh and MUT 1,25D. Cells were grown in 6-well plates and treated with 10 nM 1,25D or ethanol (1 ul/ml of medium) for 24 hours before RNA extraction. Based on quality control of extracted RNA performed with the 2100 Bioanalyzer (Agilent Technologies, Palo Alto, CA), four samples of each condition were chosen for microarray gene expression analysis, all with RNA integrity number above 8.00. Samples were processed according to manufacturer’s instructions, starting with 200 ng total RNA. Altogether, sixteen samples of labeled fragmented cDNA were hybridized to GeneChip Human Gene 2.0 ST Arrays (Affymetrix). Array data was analysed using Partek Genomics Suite, and based on quality control one array (MUT_Veh_4) was excluded. A Benjamini-Hochberg-corrected p-value cut-off of 0.05 was used for selecting significant differentially expressed genes.
Project description:Gene expression profiling of cultured skin fibroblasts obtained from patients affected with classical Ehlers Danlos syndrome (cEDS) Transcriptome-wide expression profiling using the Affymetrix Gene 1.0 ST platform comparing the gene expression pattern of cultured skin fibroblasts from 4 cEDS patients with those of 9 healthy individuals
Project description:A subset of human skin fibroblasts are phagocytic. To investigate the gene expression changes between phagocytosing and non-phagocytosing fibroblasts, fibroblasts were incubated with apoptotic human dermal microvascular endothelial cells expressing green fluorescent protein or no treatment. Treated fibroblasts were then collected after 8 hours and sorted by FACS to identify phagocytic and non-phagocytic fibroblasts. We then performed gene expression profiling analysis using data obtained from RNA-seq of these three groups of cells.
Project description:Analysis of gene expression profiling of cultured skin fibroblasts obtained from patients affected with vascular Ehlers Danlos syndrome (vEDS) Transcriptome-wide expression profiling using the Affymetrix Gene 1.0 ST platform comparing the gene expression pattern of cultured skin fibroblasts derived from three patients with vEDS with those of nine healthy individuals