Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cardiac myofibroblasts are pivotal to adaptive remodelling after myocardial infarction (MI). These normally quiescent cells invade and proliferate as a wound healing response, facilitated by activation of matrix metalloproteinases, particularly MMP-2. Following MI these reparative events occur under chronically hypoxic conditions yet the mechanisms by which hypoxia might modulate MMP-2 activation and cardiac myofibroblast invasion have not been investigated. Human cardiac myofibroblasts cultured in collagen-supplemented medium were exposed to normoxia (20% O(2)) or hypoxia (1% O(2)) for up to 48 h. Secreted levels of total and active MMP-2 were quantified using gelatin zymography, TIMP-2 and membrane-associated MT1-MMP were quantified with ELISA, whole cell MT1-MMP by immunoblotting and immunocytochemistry and MT1-MMP mRNA with real-time RT-PCR. Cellular invasion was assessed in modified Boyden chambers and migration by scratch wound assay. In the human cardiac myofibroblast, MT1-MMP was central to MMP-2 activation and activated MMP-2 necessary for invasion, confirmed by gene silencing. MMP-2 activation was substantially attenuated by hypoxia (P<0.001), paralleled by inhibition of myofibroblast invasion (P<0.05). In contrast, migration was independent of either MT1-MMP or MMP-2. Reduced membrane expression of MT1-MMP (P<0.05) was responsible for the hypoxic reduction of MMP-2 activation, with no change in either total MMP-2 or TIMP-2. In conclusion, hypoxia reduces MMP-2 activation and subsequent invasion of human cardiac myofibroblasts by reducing membrane expression of MT1-MMP and may delay healing after MI. Regulation of these MMPs remains an attractive target for therapeutic intervention.
J Mol Cell Cardiol 2009 Sep
PMID:Chronic hypoxia inhibits MMP-2 activation and cellular invasion in human cardiac myofibroblasts. 1952 58

HMGb1 is a DNA-binding protein whose role as an extracellular cytokine in inflammation and tissue regeneration has also been reported. Given the importance of keratinocytes in wound healing, we have studied the mechanism of action of HMGb1 on HaCaT keratinocytes during in vitro scratch wound repair. Western blot and confocal immunofluorescence microscopy showed that these cells express significant amounts of HMGb1, that the protein is prevalently localized in the nucleus, and that its release by cells is negligible. Western blot also showed that these cells express the HMGb1 receptor RAGE. Cell exposure to HMGb1 in the absence of serum resulted in a stimulation of cell proliferation and ERK1/2 activation. HMGb1 also accelerated the wound closure of scratch wounded cells and promoted cell migration, as evaluated by a transwell assay. The HMGb1-induced increases of cell proliferation, cell migration, and wound closure were abolished by the MEK inhibitor PD98059. Taken together, data show that, although HMGb1 is not released by HaCaT, when applied exogenously it can induce a marked increase of the wound repair of these cells. Data also suggest that HMGb1 acts via the RAGE/MEK/ERK pathway. These results bring scientific support to the potential application of HMGb1 in regenerative medicine.
Mol Cell Biochem 2009 Dec
PMID:HMGb1 promotes scratch wound closure of HaCaT keratinocytes via ERK1/2 activation. 1958 30

The LGI1 gene has been implicated in tumor cell invasion through regulation of the ERK pathway. To determine whether human prostate cancer cells (PC3, 22RV, Du145) are similarly affected by exposure to LGI1, we conducted scratch wound assays and demonstrated that the secreted LGI1 protein can reduce cell motility, an essential component of invasion and metastasis. These studies have now been extended to an in vivo mouse model of prostate cancer. Using a BAC transgenic mouse expressing a GFP reporter gene under the control of cis regulatory elements, we demonstrated that LGI1 is highly expressed in the normal prostate epithelium. To determine whether loss of LGI1 expression is associated with development and progression of murine prostate cancer, we bred the GFP reporter BAC transgenic mice with TRAMP mice which undergo early hyperplasia and progressive stages of prostate cancer. In the F1 animals, although the surrounding normal prostate epithelium expressed high levels of LGI1 in the double transgenic mice, the LGI1 gene had been inactivated even at the earliest stages of hyperplasia. This observation supports the suggestion that inactivation of LGI1 in certain cell types is related to tumor progression. Taken together these results suggest that LGI1 may be an important molecule for the arrest of prostate cancer cell invasion and possibly as a biomarker for early detection of prostate hyperplasia.
Exp Mol Pathol 2010 Feb
PMID:Inactivation of LGI1 expression accompanies early stage hyperplasia of prostate epithelium in the TRAMP murine model of prostate cancer. 1977 37

Our previous study definitely demonstrated that the mature astrocytes could undergo a de-differentiation process and further transform into pluripotential neural stem cells (NSCs), which might well arise from the effect of diffusible factors released from scratch-insulted astrocytes. However, these neurospheres passaged from one neurosphere-derived from de-differentiated astrocytes possessed a completely distinct characteristic in the differentiation behavior, namely heterogeneity of differentiation. The heterogeneity in cell differentiation has become a crucial but elusive issue. In this study, we show that purified astrocytes could de-differentiate into intermediate precursor cells (IPCs) with addition of scratch-insulted astrocyte-conditioned medium (ACM) to the culture, which can express NG2 and A2B5, the IPCs markers. Apart from the number of NG2(+) and A2B5(+) cells, the percentage of proliferative cells as labeled with BrdU progressively increased with prolonged culture period ranging from 1 to 10 days. Meanwhile, the protein level of A2B5 in cells also increased significantly. These results revealed that not all astrocytes could de-differentiate fully into NSCs directly when induced by ACM, rather they generated intermediate or more restricted precursor cells that might undergo progressive de-differentiation to generate NSCs.
Cell Mol Neurobiol 2010 Apr
PMID:Evidence for heterogeneity of astrocyte de-differentiation in vitro: astrocytes transform into intermediate precursor cells following induction of ACM from scratch-insulted astrocytes. 1988 29

Adiponectin is an important antiatherogenic adipocytokine that inhibits inflammation, insulin resistance, and oxide stress. Inflammation in the vascular adventitia is a crucial factor in the pathogenesis of atherosclerosis. Adventitial fibroblasts (AFs) can proliferate, divide into myofibroblasts, and migrate to the intima to become a new component of atherosclerotic plaque under inflammation and atherosclerosis. We investigated whether adiponectin might prevent AFs from proliferating, migrating, and transforming into myofibroblasts. Cultured AFs were stimulated with lipopolysaccharide (LPS) in the presence or absence of adiponectin. Methyl thiazolyl tetrazolium assay and migration and scratch-wound assays demonstrated that adiponectin reduced the AF proliferation and migration induced by LPS, respectively, whereas treatment with AdipoR1 small interfering (si) RNA (siAdipoR1), AMP-activated protein kinase (AMPK) siRNA (siAMPK), and an AMPK inhibitor reversed the effect. Immunocytochemistry and Western blot revealed that adiponectin reduced the transition of AFs to myofibroblasts, and treatment with siAdipoR1, siAMPK, and the AMPK inhibitor increased the transition. RT-PCR, Western blotting, and nitric oxide (NO) assay showed that adiponectin reduces induced NO synthase (iNOS) and nitrotyrosine expression and NO and ONOO(-) production induced by LPS. Treatment with siAdipoR1, siAMPK, and the AMPK inhibitor significantly attenuated adiponectin-induced phosphorylation of AMPK and its downstream target acetyl-coenzyme A carboxylase and up-regulated iNOS mRNA and protein expression, which resulted in a marked increase of NO and ONOO(-) production. In apolipoprotein E-deficient mice, immunohistochemistry of treated vascular adventitia showed that both iNOS expression and ONOO(-) production could be reversed with an adenovirus-adiponectin vector. Taken together, these results suggest that adiponectin reduces LPS-induced NO production and nitrosative stress and prevents AFs from proliferating, transforming to myoflbroblasts, and migrating to the intima, thus worsening atherosclerosis, by inhibiting the AdipoR1-AMPK-iNOS pathway in AFs.
Mol Endocrinol 2010 Jan
PMID:Adiponectin inhibits lipopolysaccharide-induced adventitial fibroblast migration and transition to myofibroblasts via AdipoR1-AMPK-iNOS pathway. 1988 16

Cells invest a significant amount of their energy synthesizing proteins, and a large portion of the energy expenditure goes into making ribosomes, the RNA-protein machines at the centre of translation. When ribosomes are damaged in a cell, i.e. during stressful conditions, cells must first recognize the damage and then mount a response. Remme et al. show that instead of having to rebuild ribosomes from scratch, bacteria can repair ribosomes by replacing damaged proteins in situ, thereby saving significant time and energy. Given the central role of translation, such repair mechanisms might be widespread in nature.
Mol Microbiol 2010 Feb
PMID:Some reassembly required. 1996 89

We recently developed a bioresponsive dextrin-recombinant human epidermal growth factor (rhEGF) conjugate as a polymer therapeutic with potential for use in the promotion of tissue repair. The aim of these studies was to use patient-derived wound fluid and fibroblasts to evaluate its potential for further development as a treatment for chronic wounds, such as venous leg ulceration, a growing clinical challenge in the aging population. First, the levels of EGF (ELISA assay), alpha-amylase and elastase (enzyme assays) were measured in patient-derived acute and chronic wound fluid. EGF was detected in acute, but not in chronic wound fluid. alpha-Amylase concentrations were higher in acute (188 IU/L), compared to chronic wound fluid (52 IU/L), but both were in the range of human serum levels. Although elastase was present in chronic wound fluid (2.1 +/- 1.2 RFU/min), none was detected in acute wound fluid. Dextrin-rhEGF incubation in chronic wound fluid led to endogenous alpha-amylase-mediated release of rhEGF (ELISA) that was maximal at 48 h. When the migration of HaCaT keratinocytes and of human fibroblasts (isolated from patient-matched, normal skin and chronic dermal wounds) was studied in vitro using the scratch wound assay, enhanced cell migration was observed in response to both free rhEGF and alpha-amylase-activated dextrin-rhEGF conjugate compared to controls. In addition, fibroblasts displayed increased proliferation (normal dermal fibroblasts approximately 160%; chronic wound fibroblasts approximately 140%) following incubation (72 h) with dextrin-rhEGF that had been exposed to physiological levels of alpha-amylase (93 IU/L). These results suggest further preclinical in vivo evaluation of dextrin-rhEGF is warranted to determine whether conjugate pharmacokinetics and rhEGF liberation into such a complex and aggressive environment can still lead to bioactivity.
Mol Pharm 2010 Jun 07
PMID:Bioresponsive dextrin-rhEGF conjugates: in vitro evaluation in models relevant to its proposed use as a treatment for chronic wounds. 2016 55

Adipose tissue develops from differentiating preadipocytes that expand and migrate. 3T3-L1 preadipocytes respond to melanin-concentrating hormone (MCH) by increasing leptin production. Here, we investigate whether MCH elicits remodeling of the actin cytoskeleton and whether this translates into altered migratory capacity of these cells. Incubation with MCH resulted in a loss of actin stress fibers accompanied by a change in morphology from a stretched-out fibroblast to a rounded cell. PMC-3881-PI, a MCH receptor 1 antagonist blocked the effect, confirming this receptor is solely responsible for MCH-mediated actin rearrangements. Both a pharmacological activator and inhibitor of phospholipase C were used to demonstrate this molecule's importance to the signaling pathway. Finally, MCH was shown to facilitate preadipocyte migration into a scratch wound, revealing a previously unknown role for MCH in the regulation of cellular migration. We conclude that MCH could influence the expansion of adipose tissue through its ability to enhance preadipocyte migration.
Mol Cell Endocrinol 2010 May 14
PMID:Melanin-concentrating hormone facilitates migration of preadipocytes. 2017 Dec 60

Wound healing requires re-epithelialization from the wound margin through keratinocyte proliferation and migration, and some growth factors are known to influence this process. In the present study, we found that the co-treatment with hepatocyte growth factor (HGF) and TGF-beta1 resulted in enhanced migration of HaCaT cells compared with either growth factor alone, and that N-acetylcysteine, an antioxidant agent, was the most effective among several inhibitors tested, suggesting the involvement of reactive oxygen species (ROS). Fluorescence-activated cell sorter analysis using 2,7-dichlorofluorescein diacetate (DCF-DA) dye showed an early (30 min) as well as a late (24 h) increase of ROS after scratch, and the increase was more prominent with the growth factor treatment. Diphenyliodonium (DPI), a potent inhibitor of NADPH oxidase, abolished the increase of ROS at 30 min, followed by the inhibition of migration, but not the late time event. More precisely, gene knockdown by shRNA for either Nox-1 or Nox-4 isozyme of gp91phox subunit of NADPH oxidase abolished both the early time ROS production and migration. However, HaCaT cell migration was not enhanced by treatment with H((2))O((2)). Collectively, co-treatment with HGF and TGF-beta1 enhances keratinocyte migration, accompanied with ROS generation through NADPH oxidase, involving Nox-1 and Nox-4 isozymes.
Exp Mol Med 2010 Apr 30
PMID:Co-treatment with hepatocyte growth factor and TGF-beta1 enhances migration of HaCaT cells through NADPH oxidase-dependent ROS generation. 2017 49

During early wound healing (WH) events Connexin 43 (Cx43) is down-regulated at wound margins. In chronic wound margins, including diabetic wounds, Cx43 expression is enhanced suggesting that down-regulation is important for WH. We previously reported that the Cx43 mimetic peptide Gap27 blocks Cx43 mediated intercellular communication and promotes skin cell migration of infant cells in vitro. In the present work we further investigated the molecular mechanism of Gap27 action and its therapeutic potential to improve WH in skin tissue and diabetic and non-diabetic cells. Ex vivo skin, organotypic models and human keratinocytes/fibroblasts of young and old donors and of diabetic and non-diabetic origin were used to assess the impact of Gap27 on cell migration, proliferation, Cx43 expression, localization, phosphorylation and hemichannel function. Exposure of ex vivo WH models to Gap27 decreased dye spread, accelerated WH and elevated cell proliferation. In non-diabetic cell cultures Gap27 decreased dye uptake through Cx hemichannels and after scratch wounding cells showed enhanced migration and proliferation. Cells of diabetic origin were less susceptible to Gap27 during early passages. In late passages these cells showed responses comparable to non-diabetic cells. The cause of the discrepancy between diabetic and non-diabetic cells correlated with decreased Cx hemichannel activity in diabetic cells but excluded differences in Cx43 expression, localization and Ser368-phosphorylation. These data emphasize the importance of Cx43 in WH and support the concept that Gap27 could be a beneficial therapeutic to accelerate normal WH. However, its use in diabetic WH may be restricted and our results highlight differences in the role of Cx43 in skin cells of different origin.
J Cell Mol Med 2011 Apr
PMID:Connexin 43 mimetic peptide Gap27 reveals potential differences in the role of Cx43 in wound repair between diabetic and non-diabetic cells. 2034 49


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