scholarly journals Antifibrotic Effects of Amyloid-Beta and Its Loss in Cirrhotic Liver

Cells ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 452 ◽  
Author(s):  
Gayane Hrachia Buniatian ◽  
Ralf Weiskirchen ◽  
Thomas S. Weiss ◽  
Ute Schwinghammer ◽  
Martin Fritz ◽  
...  
Keyword(s):  
Amyloid Beta ◽  
Potential Role ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Transforming Growth Factor Β ◽  
Cirrhotic Liver ◽  
Liver Sinusoidal Endothelial Cells ◽  
Beta Secretase ◽  
Diseased Liver

The function and regulation of amyloid-beta (Aβ) in healthy and diseased liver remains unexplored. Because Aβ reduces the integrity of the blood-brain barrier we have examined its potential role in regulating the sinusoidal permeability of normal and cirrhotic liver. Aβ and key proteins that generate (beta-secretase 1 and presenilin-1) and degrade it (neprilysin and myelin basic protein) were decreased in human cirrhotic liver. In culture, activated hepatic stellate cells (HSC) internalized Aβ more efficiently than astrocytes and HSC degraded Aβ leading to suppressed expression of α-smooth muscle actin (α-SMA), collagen 1 and transforming growth factor β (TGFβ). Aβ also upregulated sinusoidal permeability marker endothelial NO synthase (eNOS) and decreased TGFβ in cultured human liver sinusoidal endothelial cells (hLSEC). Liver Aβ levels also correlate with the expression of eNOS in transgenic Alzheimer’s disease mice and in human and rodent cirrhosis/fibrosis. These findings suggest a previously unexplored role of Aβ in the maintenance of liver sinusoidal permeability and in protection against cirrhosis/fibrosis via attenuation of HSC activation.

scholarly journals α2-Adrenergic Receptor in Liver Fibrosis: Implications for the Adrenoblocker Mesedin

Cells ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 456 ◽  
Author(s):  
Ute A. Schwinghammer ◽  
Magda M. Melkonyan ◽  
Lilit Hunanyan ◽  
Roman Tremmel ◽  
Ralf Weiskirchen ◽  
...  
Keyword(s):  
Growth Factor ◽  
Liver Fibrosis ◽  
Liver Injury ◽  
Transforming Growth Factor ◽  
Smooth Muscle Actin ◽  
Transforming Growth Factor Β ◽  
Liver Sinusoidal Endothelial Cells ◽  
Mediated Effects ◽  
Liver Sinusoids ◽  
Endothelial Nitric Oxide

The noradrenergic system is proposed to play a prominent role in the pathogenesis of liver fibrosis. While α1- and β-adrenergic receptors (ARs) are suggested to be involved in a multitude of profibrogenic actions, little is known about α2-AR-mediated effects and their expression pattern during liver fibrosis and cirrhosis. We explored the expression of α2-AR in two models of experimental liver fibrosis. We further evaluated the capacity of the α2-AR blocker mesedin to deactivate hepatic stellate cells (HSCs) and to increase the permeability of human liver sinusoidal endothelial cells (hLSECs). The mRNA of α2a-, α2b-, and α2c-AR subtypes was uniformly upregulated in carbon tetrachloride-treated mice vs the controls, while in bile duct-ligated mice, only α2b-AR increased in response to liver injury. In murine HSCs, mesedin led to a decrease in α-smooth muscle actin, transforming growth factor-β and α2a-AR expression, which was indicated by RT-qPCR, immunocytochemistry, and Western blot analyses. In a hLSEC line, an increased expression of endothelial nitric oxide synthase was detected along with downregulated transforming growth factor-β. In conclusion, we suggest that the α2-AR blockade alleviates the activation of HSCs and may increase the permeability of liver sinusoids during liver injury.

Certainties and uncertainties concerning the contribution of pericytes to the pathogenesis of systemic sclerosis

2017 ◽  
Vol 3 (1) ◽  
pp. 14-20 ◽  
Author(s):  
Rossella Talotta ◽  
Fabiola Atzeni ◽  
Maria Chiara Ditto ◽  
Maria Chiara Gerardi ◽  
Alberto Batticciotto ◽  
...  
Keyword(s):  
Systemic Sclerosis ◽  
Growth Factor ◽  
Transforming Growth Factor ◽  
Close Contact ◽  
Smooth Muscle Actin ◽  
Transforming Growth Factor Β ◽  
Biological Behaviour ◽  
Vascular Integrity ◽  
Adam 12

The role of pericytes in systemic sclerosis (SSc) is unclear because of the difficulty in phenotyping them. They are mainly distributed in the pre-capillary, capillary and post-capillary abluminal side of non-muscular micro-vessels, express platelet-derived growth factor receptors (PDGFRs), and preside over vascular integrity and regeneration. By establishing close contact with many endothelial cells, a single pericyte can regulate ion influx, mechanical stress, leukocyte diapedesis, and platelet activation. Moreover, under pathological conditions such as SSc, pericytes may acquire a contractile phenotype and respond to various stimuli, including endothelin, angiotensin II and reactive oxygen species. The pericytes of SSc patients share some molecular patterns with myofibroblasts or fibroblasts, including A disintegrin and metalloproteinase domain 12 (ADAM-12), α-smooth muscle actin (α-SMA), the extra domain A (ED-A) variant of fibronectin, and Thy-1. Following stimulation with PDGF-β or transforming growth factor-β (TGF-β), pericytes may acquire a myofibroblast phenotype, and produce extracellular matrix or indirectly promote fibroblast activation. They may also contribute to fibrosis by means of epigenetic regulation. The pericyte plasmalemma is particularly rich in caveolae containing caveolin-1, a deficit of which has been associated with defective vessel tone control and lung fibrosis in mice. Consequently, dysfunctional pericytes may underlie the microangiopathy and fibrosis observed in SSc patients. However, given its variability in biological behaviour and the lack of a pan-pericyte marker, the exact role of these cells in SSc warrants further investigation.

scholarly journals LncRNA SNHG16 promotes pulmonary fibrosis by targeting miR-455-3p to regulate the Notch2 pathway

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Panpan Liu ◽  
Lei Zhao ◽  
Yuxia Gu ◽  
Meilan Zhang ◽  
Hongchang Gao ◽  
...  
Keyword(s):  
Pulmonary Fibrosis ◽  
Lung Fibrosis ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Interstitial Lung Diseases ◽  
Luciferase Reporter ◽  
Qrt Pcr ◽  
Rna Immunoprecipitation ◽  
And Migration

Abstract Background Idiopathic pulmonary fibrosis (IPF) is the most common interstitial lung diseases with a poor prognosis. Long non-coding RNAs (lncRNAs) have been reported to be involved in IPF in several studies. However, the role of lncRNA SNHG16 in IPF is largely unknown. Methods Firstly, experimental pulmonary fibrosis model was established by using bleomycin (BML). Histology and Western blotting assays were used to determine the different stages of fibrosis and expression of several fibrosis biomarkers. The expression of SNHG16 was detected by quantitative real-time polymerase chain reaction (qRT‐PCR). EdU staining and wound-healing assay were utilized to analyze proliferation and migration of lung fibroblast cells. Molecular mechanism of SNHG16 was explored by bioinformatics, dual-luciferase reporter assay, RNA immunoprecipitation assay (RIP), and qRT-PCR. Results The expression of SNHG16 was significantly up-regulated in bleomycin-(BLM) induced lung fibrosis and transforming growth factor-β (TGF-β)-induced fibroblast. Knockdown of SNHG16 could attenuate fibrogenesis. Mechanistically, SNHG16 was able to bind and regulate the expression of miR-455-3p. Moreover, SNHG16 also regulated the expression of Notch2 by targeting miR-455-3p. Finally, SNHG16 could promote fibrogenesis by regulating the expression of Notch2. Conclusion Taken together, our study demonstrated that SNHG16 promoted pulmonary fibrosis by targeting miR-455-3p to regulate the Notch2 pathway. These findings might provide a novel insight into pathologic process of lung fibrosis and may provide prevention strategies in the future.

scholarly journals The Potential Association between the Risk of Post-Surgical Adhesion and the Activated Local Angiotensin II Type 1 Receptors: Need for Novel Treatment Strategies

2021 ◽  
pp. 1-8
Author(s):  
Mahmood Tavakkoli ◽  
Saeed Aali ◽  
Borzoo Khaledifar ◽  
Gordon A. Ferns ◽  
Majid Khazaei ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Molecular Mechanisms ◽  
Transforming Growth Factor ◽  
Therapeutic Potential ◽  
Angiotensin Receptor Blockers ◽  
Surgical Techniques ◽  
Treatment Strategies ◽  
Transforming Growth Factor Β

<b><i>Background:</i></b> Post-surgical adhesion bands (PSABs) are a common complication after abdominal or pelvic surgeries for different reasons like cancer treatment. Despite improvements in surgical techniques and the administration of drugs or the use of physical barriers, there has only been limited improvement in the frequency of postoperative adhesions. Complications of PSAB are pain, infertility, intestinal obstruction, and increased mortality. The most important molecular mechanisms for the development of PSAB are inflammatory response, oxidative stress, and overexpression of pro-fibrotic molecules such as transforming growth factor β. However, questions remain about the pathogenesis of this problem, for example, the causes for individual differences or why certain tissue sites are more prone to post-surgical adhesions. <b><i>Summary:</i></b> Addressing the pathological causes of PSAB, the potential role of local angiotensin II/angiotensin II type 1 receptors (AngII/AT1R), may help to prevent this problem. <b><i>Key Message:</i></b> The objective of this article was to explore the role of the AngII/AT1R axis potential to induce PSAB and the therapeutic potential of angiotensin receptor blockers in the prevention and treatment of PSAB.

scholarly journals The Role of Endoglin in Hepatocellular Carcinoma

2021 ◽  
Vol 22 (6) ◽  
pp. 3208
Author(s):  
Kuo-Shyang Jeng ◽  
I-Shyan Sheen ◽  
Shu-Sheng Lin ◽  
Chuen-Miin Leu ◽  
Chiung-Fang Chang
Keyword(s):  
Hepatocellular Carcinoma ◽  
Liver Diseases ◽  
Transforming Growth Factor ◽  
Antiangiogenic Therapy ◽  
Transforming Growth Factor Β ◽  
Postoperative Recurrence ◽  
Transmembrane Glycoprotein ◽  
Early Progression

Endoglin (CD105) is a type-1 integral transmembrane glycoprotein and coreceptor for transforming growth factor-β (TGF-β) ligands. The endoglin/TGF-β signaling pathway regulates hemostasis, cell proliferation/migration, extracellular matrix (ECM) synthesis and angiogenesis. Angiogenesis contributes to early progression, invasion, postoperative recurrence, and metastasis in hepatocellular carcinoma (HCC), one of the most widespread malignancies globally. Endoglin is overexpressed in newly formed HCC microvessels. It increases microvessel density in cirrhotic and regenerative HCC nodules. In addition, circulating endoglin is present in HCC patients, suggesting potential for use as a diagnostic or prognostic factor. HCC angiogenesis is dynamic and endoglin expression varies by stage. TRC105 (carotuximab) is an antibody against endoglin, and three of its clinical trials were related to liver diseases. A partial response was achieved when combining TRC105 with sorafenib. Although antiangiogenic therapy still carries some risks, combination therapy with endoglin inhibitors or other targeted therapies holds promise.

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