Stellate cells in livers of dogs with portal vein hypoperfusion

Hepatic stellate cells play a crucial role in the development of liver fibrosis. In a damaged liver, stellate cells undergo activation, which is manifested as a change of their phenotype: differentiation of stellate cells to myofibroblast-type cells, expression of alpha-Smooth Muscle Actin, their proliferation and a reduction in the size of cytoplasmic lipid droplets. The aim of this study was to determine the number and morphology of stellate cells in the canine liver affected by congenital portosystemic shunt (PSS) and portal vein hypoplasia – hepatic microvascular dysplasia (PVH-HMD). The material for investigation were archived paraffin blocks with liver samples collected supravitally from six dogs with PSS, six dogs with PVH-HMD and six healthy dogs. On the HE-stained sections, the number of stellate cells per 100 hepatocytes was counted (Sztark method) and the diameter of veins in the hepatic triads was measured (light microscope Olympus BX 43, SC30 camera, CellSens Entry 2011 Olympus). In addition, the diameter of lipid droplets in stellate cells was measured (computed image analysis system LUCIA 4.21). The results were analysed statistically (the Kruskal-Wallis test followed by Dunn’s post-hoc procedure; significance level (α) at 0.05; Statistica 12 StatSoft Inc.). The degree of liver fibrosis was determined (Masson’s method of slide stain; Scheuer scale). The liver samples from the dogs with PSS and PVH-HMD were stained immunohistochemically with Monoclonal Mouse Anti-Human Smooth Muscle Actin (α-SMA), clone 1A4, antibodies (DAKO). Portosystemic shunt and primary portal vein hypoplasia in the dog results in a reduction in the diameter of portal vein branches and in insufficient portal blood flow through the liver. In the material investigated, this was particularly evident in the animals affected by PSS: such dogs had a significantly smaller diameter of the veins than did the healthy dogs (p<0.001) or the dogs with PVH-HMD (p=0.023). Fibrosis and the expression of α-SMA were stronger in the dogs with PSS than in those with PVH-HMD. Moreover, the dogs with PSS had a significantly higher average number of stellate cells than the healthy animals (p=0.007) did. However, the examination of the material revealed an enlargement of cytoplasmic lipid droplets: the dogs with PSS had a significantly larger diameter of lipid vacuoles in the cytoplasm of stellate cells than did the healthy animals (p<0.001) or the dogs with PVH-HMD (p=0.043); the dogs with PVH-HMD had lipid droplets with a significantly larger diameter than the healthy animals (p<0.001) did. Hypoperfusion of the liver and the accompanying regressive lesions in hepatocytes result mainly in an increased number of stellate cells and stronger expression of α-SMA, while cytoplasmic lipid droplets in the stellate cells are not reduced in size. The present study indicates the need for detailed analyses of clinical cases and warrants further comprehensive studies of comparative hepatopathology because it demonstrates differences between humans and dogs in the morphological indicators of hepatic stellate cell activation in chronic liver damage.

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Structural Changes and Detection of Liver Fibrosis–Related Protein Levels in Coculture of Alveolar Echinococcosis-Protoscoleces and Human Hepatic Stellate Cells

10.21203/rs.3.rs-324820/v1 ◽

2021 ◽

Author(s):

DEping cao ◽

Emad Shamsan ◽

Bofan Jiang ◽

Zhang Yaogang ◽

Mustafa Abdo Saif Dehwah

Keyword(s):

Smooth Muscle ◽

Liver Fibrosis ◽

Hepatic Stellate Cells ◽

Structural Changes ◽

Alveolar Echinococcosis ◽

Smooth Muscle Actin ◽

Stellate Cells ◽

Enzyme Linked Immunosorbent Assay ◽

Muscle Actin ◽

Related Protein

Abstract BackgroundEchinococcus multilocularis is a causative agent of human alveolar echinococcosis (AE). AE leads to cirrhosis in several organs, such as the liver, triggering severe conditions, including hepatic failure and encephalopathy. The main purpose of this study is to explore the interaction between treated hepatic stellate cells and AE-protoscoleces (AE-PSCs). The results of this study will be provided experimental basis for revealing the mechanisms of hepatic fibrosis after AE infection.MethodsWe investigated the role of alveolar echinococcosis-protoscoleces (AE-PSCs) in liver fibrosis and structural changes and liver fibrosis-related protein expression in a coculture of PSCs and human hepatic stellate cells (HSCs). Structural changes were detected by transmission electron microscopy, whereas liver fibrosis-related proteins, collagen I, alpha-smooth muscle actin, and osteopontin levels were measured by western blotting and enzyme-linked immunosorbent assay. ResultsPSCs exhibited morphological changes, specifically changes in shape, and showed slight changes in the cytoplasmic membrane, whereas structural modifications were observed in HSCs. Additionally, western blotting and enzyme-linked immunosorbent assay revealed that PSCs treated in vitro with HSC-LX2 showed significantly increased collagen-Ⅰ, α-smooth muscle actin, and osteopontin expression levels after 3–4 days of incubation in a coculture system. AE-PSCs induced liver fibrosis by inducing extracellular matrix expression and HSC activation.ConclusionsThese results provide insight into the pathogenesis of echinococcosis- induced hepatic fibrosis and introduce therapeutic targets and diagnostic criteria for managing echinococcosis-dependent liver fibrosis.

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Dynamics of Sept4 expression in fibrotic livers of mice infected with Schistosoma japonicum

Parasitology ◽

10.1017/s0031182011000667 ◽

2011 ◽

Vol 138 (8) ◽

pp. 1003-1010 ◽

Cited By ~ 10

Author(s):

Y. N. DUAN ◽

H. Y. QIAN ◽

Y. W. QIN ◽

D. D. ZHU ◽

X. X. HE ◽

...

Keyword(s):

Smooth Muscle ◽

Liver Fibrosis ◽

Mouse Model ◽

Schistosoma Japonicum ◽

Hepatic Stellate Cells ◽

Immunohistochemical Staining ◽

Smooth Muscle Actin ◽

Stellate Cells ◽

Muscle Actin ◽

Qrt Pcr

SUMMARYIn order to investigate the dynamics of Septin4 (Sept4) expression and its function in the formation of fibrotic livers in mice infected with Schistosoma japonicum, we constructed the mouse model of S. japonicum egg-induced liver fibrosis for 24 weeks. Immunohistochemical staining, qRT-PCR and Western blot were used to detect the expression of Sept4 and α-smooth muscle actin (α-SMA). We found Sept4 localized in the perisinusoidal space where hepatic stellate cells (HSCs) distribute in the periphery of circumoval granulomas and the portal venule. The expression of Sept4 and α-SMA had a similar significant tendency of an up-regulation to a peak at 12 weeks post-infection (p.i.) followed by a down-regulation. At 24 weeks p.i. both were at a low level. These results suggest that Sept4 and α-SMA may interact together in HSCs. Based on this evidence, we hypothesize that Sept4 seems to be involved in the formation of inflammatory granulomata and subsequent liver fibrosis by regulating HSCs activation.

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Sirtuin 3 (SIRT3) Regulates α-Smooth Muscle Actin (α-SMA) Production through the Succinate Dehydrogenase-G Protein-coupled Receptor 91 (GPR91) Pathway in Hepatic Stellate Cells

Journal of Biological Chemistry ◽

10.1074/jbc.m115.692244 ◽

2016 ◽

Vol 291 (19) ◽

pp. 10277-10292 ◽

Cited By ~ 21

Author(s):

Ying Hui Li ◽

Dae Hee Choi ◽

Eun Hye Lee ◽

Su Ryeon Seo ◽

Seungkoo Lee ◽

...

Keyword(s):

Smooth Muscle ◽

Succinate Dehydrogenase ◽

G Protein ◽

Hepatic Stellate Cells ◽

Smooth Muscle Actin ◽

Stellate Cells ◽

Muscle Actin ◽

G Protein Coupled Receptor ◽

Sirtuin 3 ◽

G Protein Coupled

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The hepatitis C virus core protein indirectly induces alpha-smooth muscle actin expression in hepatic stellate cells via interleukin-8

Journal of Hepatology ◽

10.1016/j.jhep.2009.10.035 ◽

2010 ◽

Vol 52 (5) ◽

pp. 635-643 ◽

Cited By ~ 41

Author(s):

Sophie Clément ◽

Stéphanie Pascarella ◽

Stéphanie Conzelmann ◽

Carmen Gonelle-Gispert ◽

Kévin Guilloux ◽

...

Keyword(s):

Smooth Muscle ◽

Hepatitis C ◽

Hepatic Stellate Cells ◽

Core Protein ◽

Smooth Muscle Actin ◽

Stellate Cells ◽

Muscle Actin ◽

Alpha Smooth Muscle Actin ◽

Virus Core ◽

Actin Expression

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Effect of Caloric Restriction on Hepatic Sinusoidal System and Stellate Cells in Mice

Journal of Aging Research ◽

10.1155/2014/670890 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

Jian Chen ◽

Kara King ◽

Jian X. Zhang

Keyword(s):

Smooth Muscle ◽

Vitamin A ◽

Caloric Restriction ◽

Stellate Cell ◽

Smooth Muscle Actin ◽

Cell Activity ◽

Stellate Cells ◽

Activity Level ◽

Muscle Actin ◽

Old Mice

Aging associated changes in liver include reduced hepatic blood flow, increased number of stellate cells, and collagen deposits in perisinusoidal space. We tested the possibility of mitigating these changes with caloric restriction. Two-month-old mice were subjected to 30 percent caloric restriction for 12 months and then examined for the effect of caloric restriction on the sinusoidal network, collagen deposition, and the number of stellate cells. Using intravital fluorescence microscopy, assessments were made on sinusoidal diameter, density, volumetric flow, perfusion index, and autofluorescence of vitamin A that was primarily stored with lipid droplets in stellate cells. A significant effect was observed in the vitamin A autofluorescence of stellate cells; stellate cell associated fluorescence was diminished in terms of number and size of fluorescent spots. Caloric restriction reduced collagen deposits in liver sections and lowered the gene expression ofα1-(I) collagen but notα-smooth muscle actin. No differences were detected in sinusoidal dimension measurements. Our results showed that caloric restriction was effective in ameliorating the increase in stellate cells and the mild fibrosis in old mice. However, caloric restriction had no impact on stellate cell activity level as indicated by the unaffectedα-smooth muscle actin expression.

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Pulmonary Myxoma in a Sheep

Veterinary Pathology ◽

10.1354/vp.08-vp-0016-i-bc ◽

2009 ◽

Vol 46 (3) ◽

pp. 457-459 ◽

Cited By ~ 2

Author(s):

F. Ilhan ◽

Z. Yener

Keyword(s):

Smooth Muscle ◽

Smooth Muscle Actin ◽

Left Lung ◽

Stellate Cells ◽

Muscle Actin ◽

Neoplastic Cells ◽

S 100 ◽

Myxoid Matrix ◽

Uncommon Neoplasm

Pulmonary myxoma is an uncommon neoplasm. A pale tan, lobulated, and well-circumscribed mass was discovered at slaughter in the left lung of a 5-year-old sheep. Histologically, the tumor was composed of spindloid to stellate cells in a myxoid matrix. Neoplastic cells were immunohistochemically positive for vimentin but did not express cytokeratins, S-100 protein, smooth muscle actin, desmin, or p53. On the basis of the histologic and immunohistochemical findings, this tumor was diagnosed as a myxoma.

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c-Myb modulates transcription of the α-smooth muscle actin gene in activated hepatic stellate cells

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.2000.278.2.g321 ◽

2000 ◽

Vol 278 (2) ◽

pp. G321-G328 ◽

Cited By ~ 27

Author(s):

Martina Buck ◽

Dong Joon Kim ◽

Karl Houglum ◽

Tarek Hassanein ◽

Mario Chojkier

Keyword(s):

Smooth Muscle ◽

Hepatic Stellate Cells ◽

Cell Activation ◽

Stellate Cell ◽

Smooth Muscle Actin ◽

Stellate Cells ◽

Dominant Negative ◽

Muscle Actin ◽

Muscle Actin Gene ◽

High Level

Expression of α-smooth muscle actin (α-SMA) defines the phenotype of activated (myofibroblastic) hepatic stellate cells. These cells, but not quiescent stellate cells, have a high level of α-SMA and c-Myb expression, as well as increased c-Myb-binding activities to the proximal α-SMA E box. Therefore, we analyzed the role of c-Myb in α-SMA transcription and stellate cell activation. Activated primary rat stellate cells displayed a high expression of the −724 and −271 α-SMA/luciferase (LUC) chimeric genes, which contain c-Myb binding sites (−223/−216 bp). α-SMA/LUC minigenes with mutation (−219/−217 bp), truncation (−224 bp), or deletion (−191 bp) of the c-Myb binding site were not efficiently transcribed. Transfection of wild-type c-Myb into quiescent stellate cells, which do not express endogenous c-Myb, induced a ∼10-fold stimulation of −724 α-SMA/LUC expression. Conversely, expression of either a dominant-negative c-Myb basic domain mutant (Cys43 → Asp) or a c-Myb antisense RNA blocked transcription from the −724 α-SMA/LUC or −271 α-SMA/LUC in activated cells. Moreover, transfection of c- myb antisense, but not sense, RNA inhibited both expression of the endogenous α-SMA gene and stellate cell activation, whereas transfection of c- myb stimulated α-SMA expression in quiescent stellate cells. These findings suggest that c-Myb modulates the activation of stellate cells and that integrity of the redox sensor Cys43in c-Myb is required for this effect.

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LincRNA-p21 Inhibits the Wnt/β-Catenin Pathway in Activated Hepatic Stellate Cells via Sponging MicroRNA-17-5p

Cellular Physiology and Biochemistry ◽

10.1159/000472410 ◽

2017 ◽

Vol 41 (5) ◽

pp. 1970-1980 ◽

Cited By ~ 25

Author(s):

Fujun Yu ◽

Yong Guo ◽

Bicheng Chen ◽

Liang Shi ◽

Peihong Dong ◽

...

Keyword(s):

Liver Fibrosis ◽

Hepatic Stellate Cells ◽

Noncoding Rna ◽

Type I Collagen ◽

Smooth Muscle Actin ◽

Stellate Cells ◽

Type I ◽

Muscle Actin ◽

Pathway Activity ◽

Long Intergenic Noncoding Rna

Background/Aims: It is known that the activation of hepatic stellate cells (HSCs) is a pivotal step in the initiation and progression of liver fibrosis. Aberrant activated Wnt/β-catenin pathway is known to accelerate the development of liver fibrosis. microRNAs (miRNAs)-mediated Wnt/β-catenin pathway has been reported to be involved in HSC activation during liver fibrosis. However, whether long noncoding RNAs (lncRNAs) regulate Wnt/β-catenin pathway during HSC activation still remains unclear. Methods: Long intergenic noncoding RNA-p21 (lincRNA-p21) expression was detected in Salvianolic acid B (Sal B)-treated cells. Effects of lincRNA-p21 knockdown on HSC activation and Wnt/β-catenin pathway activity were analyzed in Sal B-treated cells. In lincRNA-p21-overexpressing cells, effects of miR-17-5p on HSC activation and Wnt/β-catenin pathway activity were examined. Results: LincRNA-p21 expression was up-regulated in HSCs after Sal B treatment. In primary HSCs, lincRNA-p21 expression was down-regulated at Day 5 relative to Day 2. Sal B-inhibited HSC activation including the reduction of cell proliferation, α-smooth muscle actin (α-SMA) and type I collagen was inhibited by lincRNA-p21 knockdown. Sal B-induced Wnt/β-catenin pathway inactivation was blocked down by loss of lincRNA-p21. Notably, lincRNA-p21, confirmed as a target of miR-17-5p, suppresses miR-17-5p level. Lack of the miR-17-5p binding site in lincRNA-p21 prevents the suppression of miR-17-5p expression. In addition, the suppression of HSC activation and Wnt/β-catenin pathway induced by lincRNA-p21 overexpression was almost inhibited by miR-17-5p. Conclusion: We demonstrate that lincRNA-p21-inhibited Wnt/β-catenin pathway is involved in the effects of Sal B on HSC activation and lincRNA-p21 suppresses HSC activation, at least in part, via miR-17-5p-mediated-Wnt/β-catenin pathway.

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