Chronic urotensin-II infusion induces diastolic dysfunction and enhances collagen production in rats

2010 ◽  
Vol 298 (2) ◽  
pp. H608-H613 ◽  
Author(s):  
Lavinia Tran ◽  
Andrew R. Kompa ◽  
Will Kemp ◽  
Arintaya Phrommintikul ◽  
Bing H. Wang ◽  
...  

The vasoactive peptide urotensin-II (U-II) is likely to play a key causal role in cardiac remodeling that ultimately leads to heart failure. Its contribution, specifically to the development of diastolic dysfunction and the downstream intracellular signaling, however, remains unresolved. This study interrogates the effect of chronic U-II infusion in normal rats on cardiac structure and function. The contribution of Rho kinase (ROCK) signaling to these pathophysiological changes is evaluated in cell culture studies. Chronic high-dose U-II infusion over 4 wk significantly impaired diastolic function in rats on echocardiography-derived Doppler indexes, including E-wave deceleration time (vehicle 56.7 ± 3.3 ms, U-II 118.0 ± 21.5 ms; P < 0.01) and mitral valve annulus peak early/late diastolic tissue velocity (vehicle 2.01 ± 0.19 ms, U-II 1.04 ± 0.25 ms; P < 0.01). A lower dose of U-II infusion (1 nmol·kg−1·h−1) yielded comparable changes. Diastolic dysfunction was accompanied by molecular [significant increases in procollagen-α1(I) gene expression on real-time PCR] and morphological (increases in total collagen, P < 0.05, and collagen type-I protein deposition, P < 0.001) evidence of left ventricular (LV) fibrosis following high-dose U-II infusion. The ROCK inhibitor GSK-576371 (10−7 to 10−5 M) elicited concentration-dependent inhibition of U-II (10−7 M)-stimulated cardiac fibroblast collagen synthesis and cardiac myocyte protein synthesis. Chronic U-II infusion causes diastolic dysfunction, caused by fibrosis of the LV. The in vitro data suggest that this may be in part occurring via a ROCK-dependent pathway.

2019 ◽  
Vol 13 (2) ◽  
pp. 225-237 ◽  
Author(s):  
Xueting Han ◽  
Yanyan Wang ◽  
Mingqiang Fu ◽  
Yu Song ◽  
Jingfeng Wang ◽  
...  

Abstract Diastolic dysfunction is common in various cardiovascular diseases, which could be affected by adiponectin (APN). Nevertheless, the effects of APN on diastolic dysfunction in pressure overload model induced by transverse aorta constriction (TAC) remain to be further elucidated. Here, we demonstrated that treatment of APN attenuated diastolic dysfunction and cardiac hypertrophy in TAC mice. Notably, APN also improved active relaxation of adult cardiomyocytes, increased N2BA/N2B ratios of titin isoform, and reduced collagen type I to type III ratio and lysyl oxidase (Lox) expressions in the myocardial tissue. Moreover, APN supplementation suppressed TAC-induced oxidative stress. In vitro, inhibition of AMPK by compound C (Cpc) abrogated the effect of APN on modulation of titin isoform shift and the anti-hypertrophic effect of APN on cardiomyocytes induced by AngII. In summary, our findings indicate that APN could attenuate diastolic dysfunction in TAC mice, which are at least partially mediated by AMPK pathway.


2001 ◽  
Vol 7 (S2) ◽  
pp. 648-649
Author(s):  
Y. Dong ◽  
R. Lin ◽  
C Wei

Mechanical stimuli frequently trigger signals leading to increase gene expression, protein synthesis, or mitogenesis. Cardiac fibroblasts respond to changes in ventricular hemodynamic loading by increasing matrix production in models of pressure-overload hypertrophy and myocardial infarction. Recent studies have identified some of the intracellular signaling pathways that mediate the biological effects observed upon mechanical stimulation in vitro. These include mitogenactivated protein kinases (MAPKs) and protein kinase C (PKC) family. MAPKs include extracellular signal-regulated kinase (ERK), C-Jun NH2-terminal kinase (JNK), and p38 MAPK. ERK pathway is frequently stimulated in response to mitogen.Previous studies demonstrated that mechanical stretch stimulated MAPK activities in normal adult rat cardiac fibroblasts. On the other hand, mechanical stretch also increases transcription and production of the matrix proteins collagen (type I and HI) and fibronectin in cardiac fibroblasts. MAPKs are activated by mechanical stretch during cardiac myocytes hypertrophy through both PKCdependent and independent pathways.


2021 ◽  
Vol 8 (3) ◽  
pp. 39
Author(s):  
Britani N. Blackstone ◽  
Summer C. Gallentine ◽  
Heather M. Powell

Collagen is a key component of the extracellular matrix (ECM) in organs and tissues throughout the body and is used for many tissue engineering applications. Electrospinning of collagen can produce scaffolds in a wide variety of shapes, fiber diameters and porosities to match that of the native ECM. This systematic review aims to pool data from available manuscripts on electrospun collagen and tissue engineering to provide insight into the connection between source material, solvent, crosslinking method and functional outcomes. D-banding was most often observed in electrospun collagen formed using collagen type I isolated from calfskin, often isolated within the laboratory, with short solution solubilization times. All physical and chemical methods of crosslinking utilized imparted resistance to degradation and increased strength. Cytotoxicity was observed at high concentrations of crosslinking agents and when abbreviated rinsing protocols were utilized. Collagen and collagen-based scaffolds were capable of forming engineered tissues in vitro and in vivo with high similarity to the native structures.


1991 ◽  
Vol 274 (2) ◽  
pp. 615-617 ◽  
Author(s):  
P Kern ◽  
M Menasche ◽  
L Robert

The biosynthesis of type I, type V and type VI collagens was studied by incubation of calf corneas in vitro with [3H]proline as a marker. Pepsin-solubilized collagen types were isolated by salt fractionation and quantified by SDS/PAGE. Expressed as proportions of the total hydroxyproline solubilized, corneal stroma comprised 75% type I, 8% type V and 17% type VI collagen. The rates of [3H]proline incorporation, linear up to 24 h for each collagen type, were highest for type VI collagen and lowest for type I collagen. From pulse-chase experiments, the calculated apparent half-lives for types I, V and VI collagens were 36 h, 10 h and 6 h respectively.


Author(s):  
Michel Haagdorens ◽  
Elle Edin ◽  
Per Fagerholm ◽  
Marc Groleau ◽  
Zvi Shtein ◽  
...  

Abstract Purpose To determine feasibility of plant-derived recombinant human collagen type I (RHCI) for use in corneal regenerative implants Methods RHCI was crosslinked with 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS) to form hydrogels. Application of shear force to liquid crystalline RHCI aligned the collagen fibrils. Both aligned and random hydrogels were evaluated for mechanical and optical properties, as well as in vitro biocompatibility. Further evaluation was performed in vivo by subcutaneous implantation in rats and corneal implantation in Göttingen minipigs. Results Spontaneous crosslinking of randomly aligned RHCI (rRHCI) formed robust, transparent hydrogels that were sufficient for implantation. Aligning the RHCI (aRHCI) resulted in thicker collagen fibrils forming an opaque hydrogel with insufficient transverse mechanical strength for surgical manipulation. rRHCI showed minimal inflammation when implanted subcutaneously in rats. The corneal implants in minipigs showed that rRHCI hydrogels promoted regeneration of corneal epithelium, stroma, and nerves; some myofibroblasts were seen in the regenerated neo-corneas. Conclusion Plant-derived RHCI was used to fabricate a hydrogel that is transparent, mechanically stable, and biocompatible when grafted as corneal implants in minipigs. Plant-derived collagen is determined to be a safe alternative to allografts, animal collagens, or yeast-derived recombinant human collagen for tissue engineering applications. The main advantage is that unlike donor corneas or yeast-produced collagen, the RHCI supply is potentially unlimited due to the high yields of this production method. Lay Summary A severe shortage of human-donor corneas for transplantation has led scientists to develop synthetic alternatives. Here, recombinant human collagen type I made of tobacco plants through genetic engineering was tested for use in making corneal implants. We made strong, transparent hydrogels that were tested by implanting subcutaneously in rats and in the corneas of minipigs. We showed that the plant collagen was biocompatible and was able to stably regenerate the corneas of minipigs comparable to yeast-produced recombinant collagen that we previously tested in clinical trials. The advantage of the plant collagen is that the supply is potentially limitless.


2017 ◽  
Vol 312 (3) ◽  
pp. G219-G227 ◽  
Author(s):  
Leonie Beljaars ◽  
Sara Daliri ◽  
Christa Dijkhuizen ◽  
Klaas Poelstra ◽  
Reinoud Gosens

WNT-5A is a secreted growth factor that belongs to the noncanonical members of the Wingless-related MMTV-integration family. Previous studies pointed to a connection between WNT-5A and the fibrogenic factor TGF-β warranting further studies into the functional role of WNT-5A in liver fibrosis. Therefore, we studied WNT-5A expressions in mouse and human fibrotic livers and examined the relation between WNT-5A and various fibrosis-associated growth factors, cytokines, and extracellular matrix proteins. WNT-5A gene and protein expressions were significantly increased in fibrotic mouse and human livers compared with healthy livers. Regression or therapeutic intervention in mice resulted in decreased hepatic WNT-5A levels paralleled by lower collagen levels. Immunohistochemical analysis showed WNT-5A staining in fibrotic septa colocalizing with desmin staining indicating WNT-5A expression in myofibroblasts. In vitro studies confirmed WNT-5A expression in this cell type and showed that TGF-β significantly enhanced WNT-5A expression in contrast to PDGF-BB and proinflammatory cytokines IL-1β and TNF-α. Additionally, TGF-β induces the expression of the WNT receptors FZD2 and FZD8. After silencing of WNT-5A, reduced levels of collagen type I, vimentin, and fibronectin in TGF-β-stimulated myofibroblasts were measured compared with nonsilencing siRNA-treated controls. Interestingly, the antifibrotic cytokine IFNγ suppressed WNT-5A in vitro and in vivo. IFNγ-treated fibrotic mice showed significantly less WNT-5A expression compared with untreated fibrotic mice. In conclusion, WNT-5A paralleled collagen I levels in fibrotic mouse and human livers. WNT-5A expression in myofibroblasts is induced by the profibrotic factor TGF-β and plays an important role in TGF-β-induced regulation of fibrotic matrix proteins, whereas its expression can be reversed upon treatment, both in vitro and in vivo. NEW & NOTEWORTHY This study describes the localization and functional role of WNT-5A in human and mouse fibrotic livers. Hepatic WNT-5A expression parallels collagen type I expression. In vivo and in vitro, the myofibroblasts were identified as the key hepatic cells producing WNT-5A. WNT-5A is under control of TGF-β and its activities are primarily profibrotic.


2004 ◽  
Vol 97 (6) ◽  
pp. 2228-2235 ◽  
Author(s):  
Hui Gong ◽  
Yan-Xia Wang ◽  
Yi-Zhun Zhu ◽  
Wen-Wei Wang ◽  
Ming-Jie Wang ◽  
...  

Urotensin II is a cyclic neuropeptide recently shown to play a role via its receptor GPR14 in regulating vascular tone in the mammalian cardiovascular system. The existence of GPR14 in rat heart has been validated by ligand binding assay and RT-PCR. In the present study, we investigated the cellular distribution of GPR14 protein in rat heart by using immunohistochemistry and confocal microscopic immunofluorescence double staining with antipeptide polyclonal antibodies against GPR14 and cell type markers for myocytes and endothelial cells. The direct effect of urotensin II on left ventricular contractility was further evaluated in isolated left ventricular papillary muscles of the rat. In paraffin-embedded heart sections, positive immunohistochemical staining was observed in the left ventricle but not in the right ventricle and atria. Immunofluorescence double staining revealed the cardiac myocyte as the only cell type expressing GPR14 protein in frozen heart sections as well as in isolated cardiac myocytes. There was no visible signal for GPR14 in intramyocardial coronary arteries and capillaries. The existence of GPR14 protein in rat heart was further validated by immunoprecipitation and Western blot analysis. In isolated rat left ventricular papillary muscle preparations, urotensin II induced an increase in active contractile force. GPR14 mRNA was also detected in rat heart by RT-PCR. These data provide the first direct evidence for the cellular localization of GPR14 receptor protein and a positive inotropic effect of urotensin II in normal rat heart.


2009 ◽  
Vol 423 (1) ◽  
pp. 53-59 ◽  
Author(s):  
Sebastian Kalamajski ◽  
Anders Aspberg ◽  
Karin Lindblom ◽  
Dick Heinegård ◽  
Åke Oldberg

The interactions of the ECM (extracellular matrix) protein asporin with ECM components have previously not been investigated. Here, we show that asporin binds collagen type I. This binding is inhibited by recombinant asporin fragment LRR (leucine-rich repeat) 10–12 and by full-length decorin, but not by biglycan. We demonstrate that the polyaspartate domain binds calcium and regulates hydroxyapatite formation in vitro. In the presence of asporin, the number of collagen nodules, and mRNA of osteoblastic markers Osterix and Runx2, were increased. Moreover, decorin or the collagen-binding asporin fragment LRR 10–12 inhibited the pro-osteoblastic activity of full-length asporin. Our results suggest that asporin and decorin compete for binding to collagen and that the polyaspartate in asporin directly regulates collagen mineralization. Therefore asporin has a role in osteoblast-driven collagen biomineralization activity. We also show that asporin can be expressed in Escherichia coli (Rosetta-gami™) with correctly positioned cysteine bridges, and a similar system can possibly be used for the expression of other SLRPs (small LRR proteoglycans/proteins).


2010 ◽  
Vol 23 (06) ◽  
pp. 417-423 ◽  
Author(s):  
J. M. Cissell ◽  
S. C. Milton ◽  
L. A. Dahlgren

Summary Objectives: To evaluate the effects of pros-taglandin E2 (PGE2) treatment on the metabolism of equine tendon fibroblasts in vitro to aid in investigating the response of tendon fibroblasts to injury and novel therapeutics. Methods: Superficial digital flexor tendon fibroblasts isolated via collagenase digestion from six young adult horses were grown in monolayer in four concentrations of PGE2 (0, 10, 50, 100 ng/ml) for 48 hours. Cells and medium were harvested for gene expression (collagen types I and III, cartilage oligomeric matrix protein [COMP], decorin, and matrix metalloproteinase-1, –3, and –13), biochemical analysis (glycosaminoglycan, DNA, and collagen content), and cytological staining. Results: Gene expression for collagen type I was significantly increased at 100 ng/ml PGE2 compared to 10 and 50 ng/ml. There were not any significant differences detected for gene expression of collagen type III, COMP or dec-orin or for biochemical content and cell morphology. Clinical significance: Under the conditions investigated, exogenous treatment of equine tendon fibroblasts with PGE2 failed to alter cell metabolism in a manner useful as a model of tendon injury. A model that applies cyclic strain to a three dimensional construct seeded with tendon fibroblasts may prove to be a more useful model and merits further investigation for this purpose. The ability to assess cellular responses in an environment where the cells are supported within the extracellular matrix may prove beneficial.


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