scholarly journals Stellate Cell Activation and Imbalanced Expression of TGF-β1/TGF-β3 in Acute Autoimmune Liver Lesions Induced by ConA in Mice

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Liyun Wang ◽  
Lei Tu ◽  
Jinping Zhang ◽  
Keshu Xu ◽  
Wei Qian
Keyword(s):  
Treatment Group ◽  
Liver Injury ◽  
Cell Activation ◽  
Stellate Cell ◽  
Stellate Cells ◽  
Control Group ◽  
Liver Lesions ◽  
Saline Injection ◽  
Dynamic Expression ◽  
Tgf Β1

Objective. To study the pathogenic feature of liver injury, activation of hepatic stellate cells, and dynamic expression of TGF-β1/TGF-β3 to reveal their role in liver injury induced by ConA.Methods. Mice were randomly divided into control group and ConA treatment group. ConA (20 mg/kg) was injected through vena caudalis in ConA treatment group; the controls received the same volume of saline injection. After injection for 2 h, 8 h, 24 h, and 48 h, animals were terminated. Blood, liver, and spleen were harvested. Liver function and histopathology were studied.α-SMA, vimentin, TGF-β1, and TGF-β3 were detected.Results. After ConA injection, liver damage started to increase. Expression ofα-SMA, vimentin, TGF-β1, and TGF-β3 was significantly enhanced; all above indicators reached peak at 8 h; but from 24 h after ConA injection, TGF-β3 expression began to decline, while the TGF-β1/TGF-β3 ratio at 48 h was significantly lower than control.Conclusion. (1) Autoimmune liver injury induced by ConA showed time-based features, in which the most serious liver lesions happened at 8 h after ConA injection. (2) Early activation of HSC and imbalance expression of TGF-β1 and TGF-β3 existed in ConA-induced acute autoimmune liver injury, which may be associated with liver dysfunction and the mechanisms of progression to fibrosis.

Regulation of peroxisome proliferator-activated receptor-γ in liver fibrosis

2006 ◽  
Vol 291 (5) ◽  
pp. G902-G911 ◽  
Author(s):  
Liu Yang ◽  
Che-Chang Chan ◽  
Oh-Sang Kwon ◽  
Songling Liu ◽  
Jason McGhee ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Liver Injury ◽  
Mrna Expression ◽  
Cell Activation ◽  
Stellate Cell ◽  
Stellate Cells ◽  
Collagen I ◽  
Peroxisome Proliferator ◽  
Actin Mrna

The peroxisome proliferator-activated receptors (PPARs) impart diverse cellular effects in biological systems. Because stellate cell activation during liver injury is associated with declining PPARγ expression, we hypothesized that its expression is critical in stellate cell-mediated fibrogenesis. We therefore modulated its expression during liver injury in vivo. PPARγ was depleted in rat livers by using an adenovirus-Cre recombinase system. PPARγ was overexpressed by using an additional adenoviral vector (AdPPARγ). Bile duct ligation was utilized to induce stellate cell activation and liver fibrosis in vivo; phenotypic effects (collagen I, smooth muscle α-actin, hydroxyproline content, etc.) were measured. PPARγ mRNA levels decreased fivefold and PPARγ protein was undetectable in stellate cells after culture-induced activation. During activation in vivo, collagen accumulation, assessed histomorphometrically and by hydroxyproline content, was significantly increased after PPARγ depletion compared with controls (1.28 ± 0.14 vs. 1.89 ± 0.21 mg/g liver tissue, P < 0.03). In isolated stellate cells, AdPPARγ overexpression resulted in significantly increased adiponectin mRNA expression and decreased collagen I and smooth muscle α-actin mRNA expression compared with controls. During in vivo fibrogenesis, rat livers exposed to AdPPARγ had significantly less fibrosis than controls. Collagen I and smooth muscle α-actin mRNA expression were significantly reduced in AdPPARγ-infected rats compared with controls ( P < 0.05, n = 10). PPARγ-deficient mice exhibited enhanced fibrogenesis after liver injury, whereas PPARγ receptor overexpression in vivo attenuated stellate cell activation and fibrosis. The data highlight a critical role for PPARγ during in vivo fibrogenesis and emphasize the importance of the PPARγ pathway in stellate cells during liver injury.

scholarly journals Schisandrin B Attenuates Hepatic Stellate Cell Activation and Promotes Apoptosis to Protect against Liver Fibrosis

Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 6882
Author(s):  
Zhiman Li ◽  
Lijuan Zhao ◽  
Yunshi Xia ◽  
Jianbo Chen ◽  
Mei Hua ◽  
...  
Keyword(s):  
Hepatic Fibrosis ◽  
Hepatic Stellate Cells ◽  
Cell Activation ◽  
Stellate Cell ◽  
Stellate Cells ◽  
Schisandrin B ◽  
Proliferation And Apoptosis ◽  
Induced Apoptosis ◽  
Tgf Β1 ◽  
Different Doses

The activation of hepatic stellate cells (HSC) plays a key role in the progression of hepatic fibrosis, it is essential to remove activated HSC through apoptosis to reverse hepatic fibrosis. Schisandrin B (Sch B) is the main chemical component of schisandrin lignan, and it has been reported to have good hepatoprotective effects. However, Schisandrin B on HSC apoptosis remains unclear. In our study, we stimulated the HSC-T6 and LX-2 cell lines with TGF-β1 to induce cell activation, and the proliferation and apoptosis of the activated HSC-T6 and LX-2 cells were detected after treatment with different doses of Schisandrin B. Flow cytometry results showed that Sch B significantly reduced the activity of activated HSC-T6 and LX-2 cells and significantly induced apoptosis. In addition, the cleaved-Caspase-3 levels were increased, the Bax activity was increased, and the Bcl-2 expression was decreased in HSC-T6 and LX-2 cells treated with Sch B. Our study showed that Sch B inhibited the TGF-β1-induced activity of hepatic stellate cells by promoting apoptosis.

scholarly journals Characterization of a stellate cell activation-associated protein (STAP) with peroxidase activity found in rat hepatic stellate cells.

2001 ◽  
Vol 276 (50) ◽  
pp. 47744
Author(s):  
Norifumi Kawada ◽  
Dan Bach Kristensen ◽  
Kinji Asahina ◽  
Kazuki Nakatani ◽  
Yukiko Minamiyama ◽  
...  
Keyword(s):  
Peroxidase Activity ◽  
Hepatic Stellate Cells ◽  
Cell Activation ◽  
Stellate Cell ◽  
Stellate Cells

Prolonged infusion of angiotensin II into normal rats induces stellate cell activation and proinflammatory events in liver

2003 ◽  
Vol 285 (3) ◽  
pp. G642-G651 ◽  
Author(s):  
Ramón Bataller ◽  
Erwin Gäbele ◽  
Robert Schoonhoven ◽  
Terry Morris ◽  
Mark Lehnert ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Liver Injury ◽  
Cell Activation ◽  
Stellate Cell ◽  
Elevated Serum ◽  
Inflammatory Cells ◽  
Binding Activity ◽  
Ang Ii ◽  
Dna Binding Activity ◽  
Liver Fibrogenesis

Recent evidence indicates that angiotensin II (ANG II) plays an important role in liver fibrogenesis. However, the underlying mechanisms are largely unknown. In advanced chronic liver diseases, circulating levels of ANG II are frequently elevated. We investigated the hepatic effects of prolonged systemic infusion of ANG II in normal rats. Saline or ANG II at subpressor and pressor doses (15 and 50 ng·kg-1·min-1, respectively) were infused to normal rats for 4 wk through a subcutaneous osmotic pump. Infusion of ANG II resulted in liver injury, as assessed by elevated serum liver enzymes. Livers from ANG II-perfused rats showed activation of JNK and ERK as well as increased NF-κB and activating protein-1 DNA-binding activity. Moreover, ANG II perfusion induced oxidative stress, increased concentration of proinflammatory cytokines, and upregulated the inflammatory proteins inducible nitric oxide synthase and cyclooxygenase-2. Histological examination of the livers from ANG II-infused rats showed mild portal inflammation as well as thickening and thrombosis of small hepatic vessels. ANG II-treated livers showed accumulation of CD43-positive inflammatory cells and activated hepatic stellate cells (HSCs) at the pericentral areas. A slight increase in collagen synthesis was observed, as assessed by Sirius red staining and hepatic hydroxyproline. All of these effects were observed when ANG II was perfused at subpressor and pressor doses. ANG II also accelerated the activation of primary cultured rat HSCs. In conclusion, increased systemic ANG II can induce liver injury by promoting proinflammatory events and vascular damage. ANG II-induced hepatic effects are not dependent on increase in arterial pressure.

scholarly journals Nuclear Cathepsin F Regulates Activation Markers in Rat Hepatic Stellate Cells

2008 ◽  
Vol 19 (10) ◽  
pp. 4238-4248 ◽  
Author(s):  
Gunter Maubach ◽  
Michelle Chin Chia Lim ◽  
Lang Zhuo
Keyword(s):  
Hepatic Stellate Cells ◽  
Cell Activation ◽  
Stellate Cell ◽  
Stellate Cells ◽  
Activation Process ◽  
Type I ◽  
Activation Markers ◽  
Nuclear Activity ◽  
Cystatin B ◽  
Cathepsin F

Activation of hepatic stellate cells during liver fibrosis is a major event facilitating an increase in extracellular matrix deposition. The up-regulation of smooth muscle α-actin and collagen type I is indicative of the activation process. The involvement of cysteine cathepsins, a class of lysosomal cysteine proteases, has not been studied in conjunction with the activation process of hepatic stellate cells. Here we report a nuclear cysteine protease activity partially attributed to cathepsin F, which co-localizes with nuclear speckles. This activity can be regulated by treatment with retinol/palmitic acid, known to reduce the hepatic stellate cell activation. The treatment for 48 h leads to a decrease in activity, which is coupled to an increase in cystatin B and C transcripts. Cystatin B knockdown experiments during the same treatment confirm the regulation of the nuclear activity by cystatin B. We demonstrate further that the inhibition of the nuclear activity by E-64d, a cysteine protease inhibitor, results in a differential regulation of smooth muscle α-actin and collagen type I transcripts. On the other hand, cathepsin F small interfering RNA transfection leads to a decrease in nuclear activity and a transcriptional down-regulation of both activation markers. These findings indicate a possible link between nuclear cathepsin F activity and the transcriptional regulation of hepatic stellate cell activation markers.

Possible Therapeutic Uses of Extracellular Vesicles for Reversion of Activated Hepatic Stellate Cells: Context and Future Perspectives

2021 ◽  
Vol 21 ◽  
Author(s):  
Fahim Rejanur Tasin ◽  
Debasish Halder ◽  
Chanchal Mandal
Keyword(s):  
Liver Fibrosis ◽  
Extracellular Vesicles ◽  
Hepatic Stellate Cells ◽  
Cell Activation ◽  
Stellate Cell ◽  
Stellate Cells ◽  
Target Cells ◽  
Fibrotic Liver ◽  
Paracrine Effects ◽  
Cell Therapies

: Liver fibrosis is one of the leading causes for cirrhotic liver disease and the lack of therapies to treat fibrotic liver is a major concern. Liver fibrosis is mainly occurred by activation of hepatic stellate cells and some stem cell therapies had previously reported for treatment. However, due to some problems with cell-based treatment, a safe therapeutic agent is vehemently sought by the researchers. Extracellular vesicles are cell-derived nanoparticles that are employed in several therapeutic approaches, including fibrosis, for their ability to transfer specific molecules in the target cells. In this review the possibilities of extracellular vesicles to inactivate stellate cells are summarized and discussed. According to several studies, extracellular vesicles from different sources can either put beneficial or detrimental effects by regulating the activation of stellate cells. Therefore, targeting extracellular vesicles for maximizing or inhibiting their production is a potential approach for fibrotic liver treatment. Extracellular vesicles from different cells can also inactivate stellate cells by carrying out the paracrine effects of those cells, working as the agents. They are also implicated as smart carrier of anti-fibrotic molecules when their respective parent cells are engineered to produce specific stellate cell-regulating substances. A number of studies showed stellate cell activation can be regulated by up/downregulation of specific proteins, and extracellular vesicle-based therapies can be an effective move to exploit these mechanisms. In conclusion, EVs are advantageous nano-carriers with the potential to treat fibrotic liver by inactivating activated stellate cells by various mechanisms.

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