scholarly journals Influence of Laminin Coating on the Autologous In Vivo Recellularization of Decellularized Vascular Protheses

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3351 ◽  
Author(s):  
Mahfuza Toshmatova ◽  
Sentaro Nakanishi ◽  
Yukiharu Sugimura ◽  
Vera Schmidt ◽  
Artur Lichtenberg ◽  
...  
Keyword(s):  
Inflammatory Cell ◽  
Smooth Muscle Actin ◽  
Muscle Actin ◽  
Similar Extent ◽  
Alpha Smooth Muscle Actin ◽  
Promising Strategy ◽  
Biological Implants ◽  
Significant Acceleration ◽  
The Media

Decellularization of non-autologous biological implants reduces the immune response against foreign tissue. Striving for in vivo repopulation of aortic prostheses with autologous cells, thereby improving the graft biocompatibility, we examined surface coating with laminin in a standardized rat implantation model. Detergent-decellularized aortic grafts from donor rats (n = 37) were coated with laminin and systemically implanted into Wistar rats. Uncoated implants served as controls. Implant re-colonization and remodeling were examined by scanning electron microscopy (n = 10), histology and immunohistology (n = 18). Laminin coating persisted over eight weeks. Two weeks after implantation, no relevant neoendothelium formation was observed, whereas it was covering the whole grafts after eight weeks, with a significant acceleration in the laminin group (p = 0.0048). Remarkably, the intima-to-media ratio, indicating adverse hyperplasia, was significantly diminished in the laminin group (p = 0.0149). No intergroup difference was detected in terms of medial recellularization (p = 0.2577). Alpha-smooth muscle actin-positive cells originating from the adventitial surface invaded the media in both groups to a similar extent. The amount of calcifying hydroxyapatite deposition in the intima and the media did not differ between the groups. Inflammatory cell markers (CD3 and CD68) proved negative in coated as well as uncoated decellularized implants. The coating of decellularized aortic implants with bioactive laminin caused an acceleration of the autologous recellularization and a reduction of the intima hyperplasia. Thereby, laminin coating seems to be a promising strategy to enhance the biocompatibility of tissue-engineered vascular implants.

Alpha-smooth muscle actin in pathological human disc nucleus pulposus cells in vivo and in vitro

2004 ◽  
Vol 12 (4) ◽  
pp. 430-438 ◽  
Author(s):  
Dawn Hastreiter ◽  
Jeannie Chao ◽  
QI Wang ◽  
Richard M. Ozuna ◽  
Myron Spector
Keyword(s):  
Smooth Muscle ◽  
Nucleus Pulposus ◽  
Smooth Muscle Actin ◽  
Muscle Actin ◽  
Nucleus Pulposus Cells ◽  
Alpha Smooth Muscle Actin

scholarly journals The specific NH2-terminal sequence Ac-EEED of alpha-smooth muscle actin plays a role in polymerization in vitro and in vivo.

1995 ◽  
Vol 130 (4) ◽  
pp. 887-895 ◽  
Author(s):  
C Chaponnier ◽  
M Goethals ◽  
P A Janmey ◽  
F Gabbiani ◽  
G Gabbiani ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Actin Polymerization ◽  
Smooth Muscle Actin ◽  
Muscle Actin ◽  
Alpha Smooth Muscle Actin ◽  
Fab Fragment ◽  
Acetyl Group ◽  
Antibody Complex

The blocking effect of the NH2-terminal decapeptide of alpha-smooth muscle (SM) actin AcEEED-STALVC on the binding of the specific monoclonal antibody anti-alpha SM-1 (Skalli, O., P. Ropraz, A. Trzeviak, G. Benzonana, D. Gillessen, and G. Gabbiani. 1986. J. Cell Biol. 103:2787-2796) was compared with that of synthetic peptides modified by changing the acetyl group or by substituting an amino acid in positions 1 to 5. Using immunofluorescence and immunoblotting techniques, anti-alpha SM-1 binding was abolished by the native peptide and by peptides with a substitution in position 5, indicating that AcEEED is the epitope for anti-alpha SM-1. Incubation of anti-alpha SM-1 (or of its Fab fragment) with arterial SM actin increased polymerization in physiological salt conditions; the antibody binding did not hinder the incorporation of the actin antibody complex into the filaments. This action was not exerted on skeletal muscle actin. After microinjection of the alpha-SM actin NH2-terminal decapeptide or of the epitopic peptide into cultured aortic smooth muscle cells, double immunofluorescence for alpha-SM actin and total actin showed a selective disappearance of alpha-SM actin staining, detectable at approximately 30 min. When a control peptide (e.g. alpha-skeletal [SK] actin NH2-terminal peptide) was microinjected, this was not seen. This effect is compatible with the possibility that the epitopic peptide traps a protein involved in alpha-SM actin polymerization during the dynamic filament turnover in stress fibers. Whatever the mechanism, this is the first evidence that the NH2 terminus of an actin isoform plays a role in the regulation of polymerization in vitro and in vivo.

scholarly journals Akt1 regulates pulmonary fibrosis via modulating IL-13 expression in macrophages

2019 ◽  
Vol 25 (7) ◽  
pp. 451-461 ◽  
Author(s):  
Yunjuan Nie ◽  
Yudong Hu ◽  
Kaikai Yu ◽  
Dan Zhang ◽  
Yinze Shi ◽  
...  
Keyword(s):  
Idiopathic Pulmonary Fibrosis ◽  
Pulmonary Fibrosis ◽  
Smooth Muscle Actin ◽  
In Vivo Studies ◽  
Muscle Actin ◽  
Alpha Smooth Muscle Actin ◽  
Fibrosis Progression ◽  
Matrix Components ◽  
Deficient Mice

Idiopathic pulmonary fibrosis is a progressive interstitial pneumonia characterised by fibroblast accumulation, collagen deposition and extracellular matrix (ECM) remodelling. It was reported that Akt1 mediated idiopathic pulmonary fibrosis progression through regulating the apoptosis of alveolar macrophage, while its effect on macrophage-produced cytokines remains largely unknown. In the present study, we first examined the phosphorylation of Akt1 in lung sections from idiopathic pulmonary fibrosis patients by immunohistochemistry before applying a bleomycin-induced idiopathic pulmonary fibrosis model using Akt1−/− mice and Akt1+/+ littermates. The results showed that Akt1 was remarkably up-regulated in idiopathic pulmonary fibrosis patients, while in vivo studies revealed that Akt1-deficient mice had well-preserved alveolar structure and fewer collagens, secreted fewer matrix components, including alpha smooth-muscle actin and fibronectin and survived significantly longer than Akt1+/+ littermates. Additionally, the pro-fibrogenic cytokine IL-13 was down-regulated at least twofold in Akt1−/−mice compared to the Akt1+/+group on d 3 and 7 after bleomycin treatment. Furthermore, it was found that Akt1–/– macrophages displayed down-regulation of IL-13 compared to Akt1+/+ macrophages in which Akt1 was phosphorylated in response to IL-33 stimulation. These findings indicate that Akt1 modulates pulmonary fibrosis through inducing IL-13 production by macrophages, suggesting that targeting Akt1 may simultaneously block the fibrogenic processes of idiopathic pulmonary fibrosis.

scholarly journals Fat, Cartilage, and Bone Metaplasia in Lungs of Cattle With Caudal Pleural Lesions and Subjacent Interstitial Fibrosis

2019 ◽  
Vol 56 (4) ◽  
pp. 599-603
Author(s):  
Cecilia Ramírez-Hernández ◽  
Luis Jorge García-Márquez ◽  
Horacio Decanini-Arcaute ◽  
Julio Martínez-Burnes ◽  
Rafael Ramírez-Romero
Keyword(s):  
Wilms Tumor ◽  
Interstitial Fibrosis ◽  
Smooth Muscle Actin ◽  
Mesothelial Cells ◽  
Osseous Metaplasia ◽  
Muscle Actin ◽  
Alpha Smooth Muscle Actin ◽  
Bone Metaplasia ◽  
Histology And Immunohistochemistry

The changes associated with condemned lungs in cattle with chronic pleural lesions of the caudal lobes were characterized by histology and immunohistochemistry (IHC). Fibroproliferative pleural lesions were microscopically confirmed. Occasionally, the pleural lesions also included adipose, chondroid, and osseous metaplasia that were covered by mesothelial cells, mostly in the absence of inflammation. Other lungs also showed fibrosis in the subpleural interstitium and interlobular septa. In both condemned and noncondemned lungs, immunoreactivity to Wilms tumor 1 (WT1) was normally observed on surface mesothelial cells but not on the submesothelial fibroblasts and myofibroblasts. Conversely, the myofibroblasts beneath the pleura, but not the mesothelial cells, showed immunoreactivity to alpha smooth muscle actin and calponin. However, in the lungs with myofibroblastic foci in the pleura, the proliferated cells maintained WT1 immunoreactivity similar to those of some metaplastic cells. These findings may reflect the plasticity of mesothelial cells in vivo.

Chronic iron overload causes activation of rat lipocytes in vivo

1995 ◽  
Vol 268 (3) ◽  
pp. G451-G458
Author(s):  
G. A. Ramm ◽  
S. C. Li ◽  
L. Li ◽  
R. S. Britton ◽  
R. O'Neill ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Iron Overload ◽  
Protein Production ◽  
Smooth Muscle Actin ◽  
Iron Concentration ◽  
Chow Diet ◽  
Muscle Actin ◽  
Alpha Smooth Muscle Actin ◽  
Hepatic Fibrogenesis

Chronic iron overload can result in hepatic fibrosis and cirrhosis. Activated lipocytes, through increased production of collagen and extracellular matrix, play an important role in hepatic fibrogenesis in several types of experimental liver injury, but their contribution to hepatic injury after iron overload is unknown. This study examines the effect of iron overload on lipocyte activation, in vivo. Male Sprague-Dawley rats were fed a chow diet supplemented with 1% carbonyl iron for up to 20 mo. Controls were fed the chow diet alone. Lipocytes were prepared by sequential pronase and collagenase perfusion of the livers, followed by density-gradient centrifugation. Lipocyte activation was assessed by immunohistochemistry of liver sections and by Western blot analysis of alpha-smooth muscle actin expression in freshly isolated lipocytes. In addition, to measure the biosynthetic capability of these lipocytes, collagen and noncollagen protein production was determined after 3 days in culture, using [3H]proline incorporation. The hepatic iron concentration was increased by eightfold in the iron-loaded rats, and lipocytes from these animals expressed alpha-smooth muscle actin. Collagen production was increased by 2.5-fold, and noncollagen protein production was elevated by twofold in lipocytes isolated from iron-loaded rats. In the iron-loaded livers, autofluorescent material with the characteristics of lipofusion was present in periportal zones. Chronic iron overload expression results in the activation of lipocytes, as determined by increased expression of alpha-smooth muscle actin and by increased production of both collagen and noncollagen protein. This activation may contribute to iron-induced hepatic fibrogenesis.

scholarly journals The Anti-Fibrotic Effect of Cold Atmospheric Plasma on Localized Scleroderma In Vitro and In Vivo

Biomedicines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1545
Author(s):  
Stephanie Arndt ◽  
Petra Unger ◽  
Anja-Katrin Bosserhoff ◽  
Mark Berneburg ◽  
Sigrid Karrer
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Actin ◽  
Fiber Formation ◽  
Atmospheric Plasma ◽  
Localized Scleroderma ◽  
Type I ◽  
Muscle Actin ◽  
Alpha Smooth Muscle Actin ◽  
Cold Atmospheric Plasma

Cold Atmospheric Plasma (CAP) has shown promising results in the treatment of various skin diseases. The therapeutic effect of CAP on localized scleroderma (LS), however, has not yet been evaluated. We investigated the effects of CAP on LS by comparing human normal fibroblasts (hNF), human TGF-β-activated fibroblasts (hAF), and human localized scleroderma-derived fibroblasts (hLSF) after direct CAP treatment, co-cultured with plasma-treated human epidermal keratinocytes (hEK) and with an experimental murine model of scleroderma. In hAF and hLSF, 2 min CAP treatment with the MicroPlaSterβ® plasma torch did not affect pro-fibrotic gene expression of alpha smooth muscle actin, fibroblast activating protein, and collagen type I, however, it promoted re-expression of matrix metalloproteinase 1. Functionally, CAP treatment reduced cell migration and stress fiber formation in hAF and hLSF. The relevance of CAP treatment was confirmed in an in vivo model of bleomycin-induced dermal fibrosis. In this model, CAP-treated mice showed significantly reduced dermal thickness and collagen deposition as well as a decrease in both alpha smooth muscle actin-positive myofibroblasts and CD68-positive macrophages in the affected skin in comparison to untreated fibrotic tissue. In conclusion, this study provides the first evidence for the successful use of CAP for treating LS and may be the basis for clinical trials including patients with LS.

Sign in / Sign up

Export Citation Format

Share Document