CCN1 accelerates re-epithelialization by promoting keratinocyte migration and proliferation during cutaneous wound healing.

Re-epithelialization is an essential part of wound healing and has a prominent influence on the prognosis. CCN family member 1 (CCN1 or Cysteine-rich 61, CYR61), a matricellular protein, has a potential role in the wound healing process. However, its role in re-epithelialization remains unclear. The aim of this study was to determine the expression of CCN1 in the epidermis and its effect on keratinocytes during re-epithelialization. CCN1 expression in the wounded skin was analyzed using microarray data from GEO database and detected by immunofluorescence. The results showed upregulated CCN1 during the early stages of wound healing. Human primary keratinocytes were treated with recombinant human CCN1. The results showed that CCN1 promoted keratinocyte migration and proliferation. Moreover, a full-thickness mouse skin wound model and a superficial second-degree burn mouse model treated intracutaneously with CCN1 were used for in vivo studies. Topical treatment with CCN1 protein accelerated wound closure and re-epithelialization. Additionally, longer newly-formed epithelium tongue and elevated expression of PCNA and Ki67 were detected in the CCN1-treated group 4 days post-burn. These results indicate that CCN1 accelerates re-epithelialization by promoting keratinocyte migration and proliferation, and may serve as a novel target to promote re-epithelialization.

Novel bilayer cell patch combining epidermal stem cells and angiogenic adipose stem cells for diabetic wound healing.

Diabetic foot ulcer (DFU) is one of the most severe complications in patients with diabetes. However, the development of a promising therapeutic strategy for DFU is still challenging. In this article, we demonstrate a novel bilayer cell patch, and its therapeutic effects on diabetic wound healing have been systematically investigated. The experimental results revealed that diabetes mellitus exosomes (DM-Exos) could inhibit wound healing in normal C57/B6 mice. We identified three microRNAs (miRs) including miR-15a, miR-16, and miR-214 as anti-angiogenesis factors in DM-Exos. Furthermore, angiogenic-modified adipose stem cells (ADSCs, transfected with antagomiR-15a, antagomiR-16, and antagomiR-214) were found to enhance the angiogenesis ability of human umbilical vein endothelial cells (HUVECs) by co-culture. In addition, our findings exhibited that the bilayer cell patch combining epidermal stem cells (EpSCs) and angiogenic-modified ADSCs transplantation could promote diabetic wound healing through enhancing angiogenesis and re-epithelization. These findings illustrate that the novel bilayer cell patch has great potential in diabetic wound healing.

CDH1 is Identified as A Therapeutic Target for Skin Regeneration after Mechanical Loading.

Rationale: Mechanical stimuli in the microenvironment are considered key regulators of cell function. Clinically, mechanical force (tissue expander) is widely used to regenerate skin for post-burn or trauma repair, implying that mechanical stretching can promote skin cell regeneration and proliferation. However, the underlying mechanism remains unknown. Methods: Microarray analysis was utilized to detect the hub gene. The expression of Cdh1 as examined in cells and tissues by western blot, q-PCR and immunohistochemistry staining respectively. Biological roles of Cdh1 was revealed by a series of functional in vitro and in vivo studies. Results: Microarray analysis identified Cdh1 as a hub gene related to skin regeneration during rat cutaneous mechanical loading. In vitro studies suggested that both mechanical loading and Cdh1 interference induced keratinocyte dedifferentiation and enhanced stemness, promoting cell proliferation and prevent apoptosis. Furthermore, the forkhead box O1/Krüppel-like factor 4 (FOXO1/KLF4) pathway was activated and contributed to the keratinocyte dedifferentiation. In vivo studies showed that mechanical loading and Cdh1 interference facilitated epidermal dedifferentiation and promoted dermal collagen deposition, and that Cdh1 overexpression could block such influence. Conclusions: In this study, we show that E-cadherin (CDH1), a well-known cell-cell adhesion molecule, plays a crucial role in mechanical stretch-induced skin cell regeneration and proliferation. We have shown for the first time the process by which mechanical stress is transmitted to the epidermis and induces a downstream signaling pathway to induce epidermal cells to differentiate. These findings demonstrate that Cdh1-induced keratinocyte dedifferentiation is a crucial event in mechanical stretch-mediated skin regeneration and that Cdh1 may serve as a potential therapeutic target for promoting skin regeneration.

Isorhamnetin Induces Melanoma Cell Apoptosis via the PI3K/Akt and NF-κB Pathways.

Malignant melanoma is characterized by its bad prognosis for aggressiveness, drug resistance, and early metastasis. Isorhamnetin (3'-methoxy-3,4',5,7-tetrahydroxyflavone; IH) is a natural flavonoid that has been investigated for its antitumor effects in breast cancer, colon cancer, and gastric cancer through inducing cell apoptosis. Given its role in tumor inhibition, no research has been conducted concerning its effect against melanoma. In the present study, we found that IH could significantly inhibit B16F10 cell proliferation and migration and induce B16F10 cell apoptosis. The examination on molecular mechanism revealed that IH could suppress the phosphorylation of Akt and the translocation of NF-κB, which are key factors in apoptosis-related pathways. We also detected that this process was related to the bifunctional 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatases 4 (PFKFB4) by PFKFB4 knockdown experiment. In line with in vitro study, we further provided that IH effectively inhibited tumor growth in vivo. Taken together, IH was proven to induce melanoma cell apoptosis in vitro and in vivo, which may serve as a potential agent in malignant melanoma treatment in the future.

Inhibition of FKBP10 Attenuates Hypertrophic Scarring through Suppressing Fibroblast Activity and Extracellular Matrix Deposition.

Hypertrophic scar is a pathogenic form of scar formation with no recognized treatment to date. Its molecular mechanism is related to the abnormal proliferation and transition of fibroblasts and overproduction of extracellular matrix. FKBP10 is a molecular chaperone able to regulate α-smooth muscle actin expression and pro-collagen maturation in fibroblasts. However, to our knowledge, no research has investigated the biological function of FKBP10 in scar formation to date. In this study, we aim to assess the expression and function of FKBP10 in hypertrophic scarring. Through microarray analysis, real-time reverse transcriptase-PCR and immunohistochemistry, we discovered that FKBP10 is up-regulated in human and mouse hypertrophic scars. Then we evaluated hypertrophic scar formation in mouse models treated with FKBP10 small interfering RNA and found that knockdown of FKBP10 could attenuate hypertrophic scar formation in vivo. To further explore the underlying mechanism, FKBP10 was knocked down in human hypertrophic scar fibroblasts. The in vitro results showed that FKBP10 siRNA could inhibit fibroblast activity, reduce the expression of α-smooth muscle actin and extracellular matrix components, and attenuate transforming growth factor-ß1 expression and the activation of the Smad signaling pathway. In conclusion, FKBP10 plays a crucial role in hypertrophic scar formation and might be a therapeutic target for hypertrophic scars.

Identification of hub genes related to silicone-induced immune response in rats.

Silicone implants are used widely in the field of plastic surgery and are used in a large population. However, their safety profile, especially the silicone-induced immune response, has been a major concern for plastic surgeons for decades. It has been hypothesized that there is a cause and effect relation between silicone and immunity, but this is controversial. The objective of the present study was to determine the hub genes and key pathways related to silicone implant-induced immune responses in a rat model. In addition to cluster and enrichment analyses, we used weighted gene co-expression network analysis (WGCNA) to examine the gene expression profiles in a systematic context. A total five genes (Fes, Aif1, Gata3, Tlr6, Tlr2) were identified as hub genes that are most likely related to the silicone-induced immune response, four of which (Aif1, Gata3, Tlr6, Tlr2) have been associated with autoimmunity as target genes or disease markers. The Toll-like receptor signaling pathway (p < 0.01, fold enrichment: 7.01) and systemic lupus erythematosus signaling pathway (p < 0.05, fold enrichment: 5.01), which are considered strongly associated with autoimmunity, were significantly enriched in the silicone-implanted skin samples. The results indicate that silicone implants might trigger the localized immune response, as various immune reaction genes were detected after silicone implantation. The identified five hub genes will hopefully serve as novel therapeutic targets for silicone-related complications and the associated autoimmune diseases.