Project description:Pathological scarring is a fibroproliferative disorder characterised by abnormal fibroblast function and excessive deposition of extracellular matrix. In this study, based on the results of preliminary single-cell sequencing, we identified an enriched fibroblast subpopulation in keloids, which highly expresses TAGLN. In this study, we investigated the roles of TAGLN in the pathogenesis of pathological scars, respectively. And functional assays revealed that downregulation of TAGLN inhibited the motility activity and secretory functions of pathological scar fibroblasts, including invasion, migration, contraction and collagen secretion. We identified downstream targets of TAGLN by RNA-seq results analysis and further validation in. This study provides new perspectives for understanding pathological scarring and possible targets for clinical treatment.
Project description:Full thickness and deep partial thickness burn injuries heal by scarring. There are several mechanisms thought to be essential for the development of burn scars, but a challenge to studying the skin response to burn injury is that there are few animal models of burn scarring that are either clinically similar to human burn scars or are practical for most investigators to use. The purpose of this study was to examine the changes in RNA expression in human skin to burn injury. This was done by comparing pre-injury tissue from otherwise healthy adults undergoing aesthetic scarification created by branding with a hot metal object to serial samples of untreated wounds in the same subjects.
Project description:Hypertrophic skin scarring following dermal injury causes extreme pain and psychological trauma for patients. Unfortuately, we do not have effective treatments to prevent or reverse skin scarring. Using RNA and ATAC sequencing of mouse and human fibroblasts, we show that JUN expressing fibroblasts are responsible for skin scarring by regulating CD36 expression. In summary, we show that CD36 antagonism by represent a therapeutic target to overcome JUN hypertrophic skin scarring.
Project description:Hypertrophic and atrophic scars are the effect of a dysregulated wound-healing process in genetically predisposed individuals. The genetic predisposition has acquired significant attention due to the diverse phenotype of pathological scarring in individuals with a positive personal and family history. Recent studies have identified telomere shortening and decreased hTERT activity in pathological scarring, proposing the rs2736100 variant of human telomerase reverse transcriptase (hTERT) gene as a valuable variant gene candidate. We examined the scarring process in 71 female patients who had undergone Caesarean section and developed hypertrophic and atrophic scars with the objective to investigate the role of single nucleotide polymorphism (SNP) rs2736100 in pathological scarring. Genotyping was performed using RT-PCR and follow-up included the Patient Observer Scar Assessment Scale (POSAS) and SCAR scales. Comparative analysis for mean POSAS value between the check-ups at 3 and 6 months revealed a statistical decreased difference of 1.71 points [95% confidence interval (CI), 0.4-2.89; P=0.01], while SCAR highlighted a decreased difference of 0.670 (95% CI, -0.04-1.38; P=0.055). The C variant allele revealed a borderline statistical value for the risk of developing pathological scarring (OR=1.44; 95% CI, 0.876-1.332: P=0.066). In our study a pre-conceptional body mass index (BMI) >25 kg/m2 was statistically associated with pathological scarring. The Fitzpatrick type 4 phototype displayed an increased frequency for the heterozygous genotype in the current study, and it was demonstrated that dark skin tone was associated with abnormal scar formation. Our study investigated the role of hTERT gene variant rs2736100 in hypertrophic and atrophic scarring in a Caucasian population group. We report a borderline statistically significant value for the variant C allele of hTERT SNP for the risk of developing pathological scarring in female patients that had undergone Caesarean section.
Project description:We established a hypertrophic scar-like animal model using traction force in C57BL/6J mice to demonstrate the crucial mechanistic effect of TEM1 on pathological scarring. Samples from scar areas in sham and traction groups of Tem1WT/WT and Tem1lacZ/lacZ mice were subjected to RNA sequencing.
Project description:Injury in mammals induces a connective tissue response to either regenerate as before, or to scar. The fibroblastic actions and mechanisms that underlie these connective tissue responses remain obscure, as direct observation in animals is too difficult and current assays do not faithfully reproduce physiology. Here, we developed a skin explant technique termed scar-in-a-dish (SCAD) that faithfully recapitulates uniform scars with contraction and reveals how scarring occurs in unprecedented detail. By growing mouse SCADs, with a traceable scar-progenitor fibroblast lineage, we observed previously unseen intercellular connections form between scar-progenitors that then collectively swarm into the nascent wound in highly regular periodic movements that progressively contract the skin and form scars. Swarming is exclusive to scar progenitors and absent from oral cavity fibroblasts that regenerate scarless. By testing a panel of adhesion molecules that might instigate intercellular connections, we found swarming was induced by the upregulation of N-cadherin in scar progenitors. Impeding N-cadherin binding inhibited swarming and contraction, and led to reduced scarring in SCAD and in mice. Blocking N-cadherin and scar-progenitor swarming thus provides a novel therapeutic space to curtail pathological fibrotic responses across a range of medical settings.
Project description:Purpose: The physiological cardiac hypertrophy is an adaptive condition that does not associate with myocyte cell death while pathological hypertrophy is a maladaptive condition associated with myocyte cell death. Alpha-2 macroglobulin (α-2M) an acute phase protein induces cardiac hypertrophy via the ERK1,2 and PI3K/Akt signaling. This study is aimed at exploring the miRNome of α-2M induced hypertrophied cardiomyocytes and to understand the role of miRNAs in determination of pathological and physiological hypertrophy. Methods: Hypertrophy was induced in H9c2 cardiomyoblasts using alpha-2 macroglobulin. The induction of hypertrophy is confirmed by microscopy and gene expression studies. Subsequently, the total RNA was isolated and small RNA sequencing was executed in Illumina HiSeq 2000. Results: Analysis of small RNA reads revealed the differential expression of a large set of miRNAs during hypertrophy. Among the differentially expressed candidates, miR-99 family (miR-99a, miR-99b and miR-100) showed significant downregulation upon α-2M treatment while isoproterenol treatment (pathological hypertrophy) upregulated their expression. The binding site for Egr1 transcription factor was identified in the promoter region of miR-99 family, and interestingly all miRNAs with Egr1 binding site proven by ChIP-Seq were downregulated during physiological hypertrophy Conclusions: The results proved Egr-1 mediated regulation of miR-99 family determines the uniqueness of pathological and physiological hypertrophy. Upregulated miR-99 expression during pathological hypertrophy suggests that it can be a valuable diagnostic marker and potential therapeutic target for cardiac hypertrophy and heart failure. Small RNA profiles of control and hypertrophied cardiomyocyte H9c2 cells were generated by deep sequencing using Illumina HiSeq 2000