MMP-1 Expression In Fibroblasts Research Articles

Interleukin-24: A molecular mediator of particulate matter’s impact on skin aging

Air pollution, a global health concern, has been associated with adverse effects on human health. In particular, particulate matter (PM), which is a major contributor to air pollution, impacts various organ systems including the skins. In fact, PM has been suggested as a culprit for accelerating skin aging and pigmentation. In this study, using single-cell RNA sequencing, IL-24 was found to be highly upregulated among the differentially expressed genes commonly altered in keratinocytes and fibroblasts of ex vivo skins exposed to PM. It was verified that PM exposure triggered the expression of IL-24 in keratinocytes, which subsequently led to a decrease in type I procollagen expression and an increase in MMP1 expression in fibroblasts. Furthermore, long-term treatment of IL-24 induced cellular senescence in fibroblasts. Through high-throughput screening, we identified chemical compounds that inhibit the IL-24-STAT3 signaling pathway, with lovastatin being the chosen candidate. Lovastatin not only effectively reduced the expression of IL24 induced by PM in keratinocytes but also exhibited a capacity to restore the decrease in type I procollagen and the increase in MMP1 caused by IL-24 in fibroblasts. This study provides insights into the significance of IL-24, illuminating mechanisms behind PM-induced skin aging, and proposes IL-24 as a promising target to mitigate PM-associated skin aging.

Effect of iPSCs-derived keratinocytes on healing of full-thickness skin wounds in mice

Induced pluripotent stem cells (iPSCs) provide new approaches for the management of severe skin wound healing due to their infinite proliferative capacity, pluripotency into multiple lineages, and important ethical acceptability. In this study, we aimed to differentiate iPSCs into keratinocytes and to observe the therapeutic effects of transplanted iPSCs-derived keratinocytes on wound healing in mice. Here, mouse iPSCs had been successfully differentiated into keratinocytes. Next, iPSCs-derived keratinocytes labeled by CSFE were injected directly into the full-thickness skin wound. Hematoxylin & Eosin, Masson's trichrome, EdU staining and immunohistochemical staining were performed to assess the effects of iPSCs-derived keratinocytes on wound healing. Our results showed that transplantation of iPSCs-derived keratinocytes into full-thickness skin wound site accelerated re-epithelialization and reduced scar formation. In addition, we found that conditioned medium of iPSCs-derived keratinocytes reduced the expression of α-SMA and COL1 and increased the expression of MMP1 in fibroblasts in vitro. Further mechanism studies show the TNF-α-induced activation of NF-κB is involved in the effect of conditioned medium of iPSCs-derived keratinocytes on fibroblasts. In conclusion, this study has shown that iPSCs-derived keratinocytes decrease the healing time by increasing the epithelization rate and reduce scarring, suggesting a possible new treatment for skin wound healing.

Platelet factor 4 upregulates matrix metalloproteinase-1 production in gingival fibroblasts.

Periodontitis is a highly prevalent chronic inflammatory disease that causes tooth loss, morbidity and confers an increased risk for systemic disease. Tissue destruction during periodontitis is due in large part to collagen-degrading matrix metalloproteinases (MMPs) released by resident cells of the periodontium in response to proinflammatory cytokines. Platelets are immune-competent blood cells with a newly recognized role in chronic inflammation; however, their role in the pathogenesis of periodontitis is undefined. Consequently, the objective of this study was to assess the effect of platelet factor 4 (PF4), a major platelet-derived cytokine, on MMP-1 (collagenase) expression in human gingival fibroblasts (HGFs). HGFs were cultured in the presence or absence of recombinant PF4. Pro-MMP-1 secretion was quantified by enzyme-linked immunosorbent assay analysis of the cell culture supernatants. MMP-1 transcription was quantified by real-time polymerase chain reaction. Regulation of MMP-1 production by the p44/42 MAP kinase (MAPK) signaling pathway was examined in the presence or absence of PF4. Exposure to PF4 caused a ~ 2-3-fold increase in MMP-1 transcription and secretion from cultured HGFs. PF4 treatment also enhanced phosphorylation of p44/42 MAPK, which has been previously shown to induce MMP-1 expression in fibroblasts. Blockade of p44/42 MAPK signaling with the cell-permeant inhibitors PD98059 and PD184352 abrogated PF4-induced pro-MMP-1 transcription upregulation and release from cultured HGFs. We conclude that PF4 upregulates MMP-1 expression in HGFs in a p44/42 MAPK-dependent manner. These findings point to a previously unidentified role for platelets in the pathogenesis of periodontal diseases.

Triolein reduces MMP-1 upregulation in dermal fibroblasts generated by ROS production in UVB-irradiated keratinocytes

BackgroundCytokine production and oxidative stress generated by ultraviolet radiation B (UVB) skin exposure are main factors of skin photoaging. Interleukin-6 (IL-6) produced by irradiated keratinocytes is proposed to have a role in metalloproteinases (MMPs) expression activation in dermal fibroblasts. ObjectivesWe examined the effect of triolein treatment of UVB-irradiated keratinocytes on MMP1 (interstitial collagenase) expression response of dermal fibroblasts. We assayed UVB-irradiated keratinocytes soluble signals, mainly IL-6 and reactive oxygen species (ROS). MethodsIL-6 expression and ROS generation were assayed in UVB-irradiated keratinocytes. MMP1 mRNA expression response was assayed in fibroblasts grown in keratinocytes conditioned medium. We evaluated the effect of treating keratinocytes with triolein on IL-6 expression and ROS generation in keratinocytes, and MMP1 expression in fibroblasts. ResultsThe irradiation of epidermal cells with sublethal UVB doses increased IL-6 expression and ROS generation. Conditioned culture medium collected from keratinocytes was used to culture dermal fibroblasts. MMP1 mRNA expression increase was observed in fibroblasts cultured in medium collected from UVB-irradiated keratinocytes. Triolein treatment reduced the IL-6 expression and ROS generation in keratinocytes and this effect was reflected in downregulation of MMP1 expression in fibroblasts. ConclusionsTriolein reduces both the expression of IL-6 and ROS generation in irradiated keratinocytes. It seems to exert an anti-inflammatory and anti-oxidative stress effect on irradiated keratinocytes that in turn reduces MMP1 expression in dermal fibroblasts. Collectively, these results indicate that triolein could act as a photoprotective agent.

Luteolin Prevents Solar Radiation-Induced Matrix Metalloproteinase-1 Activation in Human Fibroblasts: A Role for p38 Mitogen-Activated Protein Kinase and Interleukin-20 Released from Keratinocytes

Human skin is continuously exposed to solar radiation, which can result in photoaging, a process involving both dermal and, to a lesser extent, epidermal structures. Previously, we have shown that the flavonoid luteolin protects the epidermis from ultraviolet (UV)-induced damage by a combination of UV-absorbing, antioxidant, and antiinflammatory properties. The aim of the present study was to determine direct and indirect effects of luteolin on dermal fibroblasts as major targets of photoaging. Stimulation of fibroblasts with UVA light or the proinflammatory cytokine interleukin-20 (IL-20) is associated with wrinkled skin, increased IL-6 secretion, matrix metalloproteinase (MMP-1) expression, and hyaluronidase activity. All of these targets were inhibited by luteolin via interference with the p38 mitogen-activated protein kinase (MAPK) pathway. Next, we assessed the role of conditioned supernatants from keratinocytes irradiated with solar-simulated radiation (SSR) on nonirradiated dermal fibroblasts. In keratinocytes, luteolin inhibited SSR-induced production of IL-20, also via interference with the p38 MAPK pathway. Similarly, keratinocyte supernatant-induced IL-6 and MMP-1 expression in fibroblasts was reduced by pretreatment of keratinocytes with luteolin. Finally, these results were confirmed ex vivo on skin explants treated with luteolin before UV irradiation. Our results suggest that SSR-mediated production of soluble factors in keratinocytes is modulated by luteolin and may attenuate photoaging in dermal fibroblasts.

019 Stratifin-Induced MMP-1 in Fibroblast is Mediated by c-Fos and P38 MAPK Activation

A delicate balance between synthesis of extracellular matrix (ECM) and degradation by matrix metalloproteinases (MMPs) is a key factor in maintaining the structural integrity of normal skin. Epidermal-mesenchymal interactions play a critical role in controlling the expression of MMPs during development and healing of skin. Disruption of this interaction increases the frequency of developing fibrotic conditions such as hypertrophic scarring and keloids. In the absence of epithelialization, ECM continues to accumulate until dermal fibroblasts receive signal(s) from epidermal cells to slow down the dynamic process of maturation and remodeling of the healing wound. We have recently demonstrated that keratinocyte releasable stratifin stimulates MMP-1 expression in dermal fibroblasts. However, the molecular mechanism by which stratifin protein induces MMP-1 expression in fibroblasts is unknown. Therefore, the purpose of the present study is to identify elements of the signaling pathway mediating stratifin stimulation of fibroblast MMP-1 expression. We did so by examining the three distinct MAPK pathways: ERK1/2, JNK, and p38 as well as the expression of the main components of the AP-1 dimers, c-Jun and c-Fos, which are mediated by distinct MAPK pathways. Our data shows that treatment of fibroblasts with stratifin resulted in rapid and transient up-regulation of c-jun and c-fos mRNA levels. Furthermore, we show that stratifin activates fibroblast MMP-1 expression at the mRNA and protein levels and this is mediated by p38 MAP kinase. Subsequent cDNA microarray analysis of fibroblasts treated with stratifin show an increase in a ternary complex factor, Sap-1. In conclusion, our results describes the mechanism by which stratifin activates MMP-1 in fibroblast, and demonstrates that p38 MAP kinase is an important regulator of MMP-1 gene expression involved in epidermal-mesenchymal interactions in wound remodeling. Acknowledgment: This work was supported by the Canadian Institute of Health Research (CIHR).

Potential role of KDAF in regulation of airway remodeling in asthma

Rationale Subepithelial fibrosis is a major feature of airway remodeling in asthma characterized by increased deposition of collagen and decreased ability of fibroblasts to produce collagenase. Our group has recently identified a family of proteins, keratinocyte anti-fibrogenic factor (KDAF) that induce collagenase expression in dermal fibroblasts. We examined the ability of lung epithelial cells to release KDAF and assessed its effect on collagenase production from fibroblasts, in vitro. We also studied antifibrotic effects of KDAF in the presence of transforming growth factor-β 1(TGF-β 1), a known contributor to the development of peribronchiolar fibrosis in asthma. Methods A549 and HS24 cell lines were incubated with low FBS concentration medium for 24 h. The epithelial conditioned medium (CM) was subjected to Western blot analysis to detect KDAF. MMP-1 and type I collagen mRNA expression was examined by Northern blot analysis following treatment (24 hr) with CM and recombinant KDAF (2.5μg/ml). The effect of TGF-β 1(150 pg/ml) on production of MMP-1 was examined in the presence and absence of recombinant KDAF (2.5 μg/ml) and CM. Results A549 and HS24 epithelial cells released measurable KDAF the latter increased MMP-1 expression and decreased type I collagen production in fetal fibroblasts. Upregulation of MMP-1 expression in fibroblasts was sustained following treatment with TGF-β 1 in the presence of CM and recombinant KDAF. Conclusions Lung epithelial cell-derived KDAF appears to have potent antifibrotic effects. We postulate that reduction of KDAF in asthmatic airways may contribute to the development of profibrotic events leading to airway remodeling.