scholarly journals Investigating the expression of autophagy genes during the in vitro activation of mouse hepatic stellate cells

2021 ◽  
Vol 63 (2) ◽  
pp. 21-26
Author(s):  
Minh Thanh Dang ◽  
◽  
Van Trinh Le ◽  
Quang Huy Do ◽  
Thi Hang Tran ◽  
...  

This study aims to evaluate the expression level of autophagy genes during the activation of mouse hepatic stellate cells (HSCs) in vitro. The HSCs isolated from the mouse liver were cultured in vitro for 7 days. The activation of HSCs was evaluated by their morphology, the storage of lipid droplets by oil red O (ORO) staining, the expression of activation-related genes α-sma, collagen I, and quiescence-related gene lrat by qRT PCR and ICC staining (α-SMA). The expression of autophagy genes lc3b, beclin 1, atg12 were assessed by qRT PCR and ICC staining (LC3). The results showed that the isolated HSCs were activated after 3 days and 7 days of the culture in vitro. The activation was indicated by the morphological change of HSCs to myofibroblast-like cells, loss of lipid droplets, and increased expression of fibrotic genes α-sma and collagen I, decreased expression of lrat. Additionally, the expression of autophagy genes lc3b, beclin 1, and atg12 were significantly increased in the activated HSCs after the culture in vitrofor 3 and 7 days. This study contributes the preliminary results to further studies on the role of autophagy during the activation of HSCs, which may be exploited for the development of the antifibrotic therapy targeting autophagy.

2016 ◽  
Vol 94 (3) ◽  
pp. 229-235 ◽  
Author(s):  
Zhenghong Li ◽  
Qidi Zhang ◽  
Qingqing Zhang ◽  
Mingyi Xu ◽  
Ying Qu ◽  
...  

Hepatocyte proliferation and collagen I (COLI) secretion are important processes during liver regeneration. This study aimed to investigate the role of CXCL6 in hepatocyte proliferation and COLI secretion. Serum CXCL6 levels in patients with chronic hepatitis B (CHB) were examined and the effects of CXCL6 on the proliferation of L02 hepatocytes and the secretion of COLI from LX2 human hepatic stellate cells were evaluated. We found that serum CXCL6 levels increased gradually with disease progression of CHB, and there was positive correlation between serum CXCL6 level and alanine transaminase (ALT) and aspartate transaminase (AST). In vitro, CXCL6 promoted L02 proliferation but this was blocked upon CXCR1 knockdown. The level of phospho-IκBα was upregulated by CXCL6 but downregulated by CXCR1 siRNA in L02 cells. CXCL6 inhibited the secretion of COLI by LX2 cells, dependent on CXCR1 and CXCR2. Taken together, these data suggest that increased expression of CXCL6 during CHB could promote hepatocyte proliferation through the CXCR1–NFκB pathway and inhibit the secretion of COLI by hepatic stellate cells.


2018 ◽  
Vol 315 (5) ◽  
pp. G713-G721 ◽  
Author(s):  
Loretta L. Jophlin ◽  
Yiannis Koutalos ◽  
Chunhe Chen ◽  
Vijay Shah ◽  
Don C. Rockey

Loss of retinyl ester (RE)-rich lipid droplets (LDs) from hepatic stellate cells (HSCs) is cited as a key event in their cellular transdifferentiation to activated, pro-fibrotic myofibroblasts; however, it remains unclear if changes in LD morphology or RE content are causal for transdifferentiation. To better understand LD dynamics in vitro within a common model of HSC activation, we used novel approaches preserving LD morphology and allowing for quantitation of RE. The size and quantity of LDs within in vitro and in vivo bile duct ligation (BDL)-activated HSCs were quantitated using adipocyte differentiation-related protein (ADRP) labeling and oil red o (ORO) staining (gold standard), and RE content was determined using fluorescence microscopy. We found during HSC activation in vitro that LD number differed significantly when measured by ADRP and ORO, respectively ( day 1: 56 vs. 5, P = 0.03; day 4: 101 vs. 39, P = 0.03; day 14: 241 vs. 12, P = 0.02). Ex vivo HSCs activated in vivo contained the same number of LDs as day 4 in vitro activated HSCs (118 vs. 101, P = 0.54). Decline in LD RE occurred beyond day 4 in vitro and day 1 ex vivo , after HSC transdifferentiation was underway. Lastly, in situ HSCs examined using electron microscopy show LDs tend to be smaller but are ultimately retained in BDL injured livers. Therefore, we conclude that during HSC transdifferentiation, LDs are not lost but are retained, decreasing in size. Additionally, RE content declines after transdifferentiation is underway. These data suggest that these LD changes are not causal for HSC transdifferentiation. NEW & NOTEWORTHY Loss of retinoid-laden lipid droplets from hepatic stellate cells has long been held as a hallmark of their transdifferentiation into activated myofibroblasts, the dominant cells that drive hepatic fibrosis. This study demonstrates that stellate cells activated in culture and after liver injury in vivo retain their lipid droplets and that these droplets become smaller and more numerous, with decreases in droplet retinoid concentration occurring only after cellular transdifferentiation is underway.


2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Li-Ying Song ◽  
Yu-Tao Ma ◽  
Cui-Fang Wu ◽  
Chun-Jiang Wang ◽  
Wei-Jin Fang ◽  
...  

Background and Aim. Aberrant activation of the TGF-β1/Smad pathway contributes to the activation of hepatic stellate cells (HSCs). MicroRNA-195 has been shown to regulate the activation of HSCs. The aim of this study was to investigate the role of miRNA-195 in HSCs activation. Methods. A liver fibrotic rat model induced by diethylnitrosamine was established. Dual luciferase reporter assays were performed to verify that Smad7 was the target of miRNA-195. The expression levels of miR-195, Smad7, and α-SMA in HSC-T6 transfected, respectively, with miR-195 mimic, inhibitor, or control were measured by qRT-PCR. The protein expression of Smad7 was detected by Western blot analysis. Results. Enhanced miR-195 and decreased Smad7 were observed in diethylnitrosamine-induced liver fibrotic rats (P<0.05). Dual luciferase reporter assays showed that the miR-195 mimic significantly suppressed the luciferase activity of a reporter plasmid carrying the binding site of miR-195 on the 3′UTR of Smad7 (P<0.05). The miR-195 mimics activated HSCs, further elevated miR-195 and α-SMA (P<0.01), and reduced the Smad7 level (P<0.05). The miR-195 inhibitors blocked the activation of HSCs, reduced the expression of miR-195 and α-SMA (P<0.01), and upregulated the expression of Smad7 (P<0.05). Conclusion. Collectively, we demonstrated that miRNA-195 activated HSCs by targeting Smad7.


BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Xia Liao ◽  
Yang Bu ◽  
Fan Chang ◽  
Fengan Jia ◽  
Ge Song ◽  
...  

Abstract Background Hepatic stellate cells (HSCs) have a key role in fibrogenesis and in the filtrates of the hepatocellular carcinoma (HCC) stroma, in which they are remodeled and play a critical role in HCC progression. However, the precise role of HSCs trending, infiltration and paracrine in orchestrating the stroma-derived oxaliplatin-resistance in HCC is still vague. Methods The chemo-resistant models were established to explore the correlation between HSC cells and the condition of chemoresistance. The HCC clinical samples were collected to confirm this phenomenon. Then, the relationship between secretory CCN3 from oxaliplatin-resistant HCC and the infiltration of HSCs in associated HCC microenvironment was evaluated. Finally, the role and mechanism of HSCs remodeling in the orchestration of oxaliplatin-resistant HCC were explored. Results The increased infiltration of HSCs and collagen accumulation were found in the microenvironment of oxaliplatin-resistant HCC. The cDNA profiles of the oxaliplatin-resistant HCC was reanalyzed, and CCN3 was one of the significantly increased genes. In HCC clinical samples, the levels of CCN3 and α-SMA are positively correlated, and high expression of CCN3 and α-SMA are positively associated with malignant phenotype and poor prognosis. Then the enhanced abilities of migration and proliferation of HSCs, and elevation of the cytokines paracrine from HSCs relating to HCC malignancy were proved in vitro and in vivo, and which were related to CCN3-ERK signaling pathway activation. Conclusions HSCs remodeling are positively related to CCN3 paracrine in hepatocellular carcinoma, which orchestrated the stroma-derived resistance to chemotherapy in HCC.


Pharmaceutics ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 676 ◽  
Author(s):  
Gina Valentino ◽  
Cristina Zivko ◽  
Florian Weber ◽  
Lorine Brülisauer ◽  
Paola Luciani

The pivotal role of hepatic stellate cells (HSCs) in orchestrating the bidirectional process of progression and regression of liver fibrosis makes them an ideal target for exploring new antifibrotic therapies. Essential phospholipids (EPLs), with their polyenylphosphatidylcholine (PPC) fraction, either alone or combined with other hepatoprotective substances such as silymarin, are recommended in hepatic impairment, but a scientific rationale for their use is still lacking. Herein, we compared the ability of EPLs to restore quiescent-like features in HSCs with that of dilinoleoylphosphatidylcholine (DLPC), PPC fraction’s main component. Specifically, we screened at the cellular level the antifibrotic effects of PPC formulations in the presence and absence of silymarin, by using LX-2 cells (pro-fibrogenic HSCs) and by assessing the main biochemical hallmarks of the activated and deactivated states of this cell line. We also proved the formulations’ direct effect on the motional order of cell membranes of adherent cells. LX-2 cells, examined for lipid droplets as a quiescence marker, showed that PPCs led to a more prominent deactivation than DLPC. This result was confirmed by a reduction of collagen and α-SMA expression, and by a profound alteration in the cell membrane fluidity. PPC–silymarin formulations deactivated HSCs with a significant synergistic effect. The remarkable bioactivity of PPCs in deactivating fibrogenic HSCs paves the way for the rational design of new therapeutics aimed at managing hepatic fibrosis.


2004 ◽  
Vol 287 (1) ◽  
pp. G18-G26 ◽  
Author(s):  
Fabio Marra ◽  
Wanda Delogu ◽  
Ilaria Petrai ◽  
Sabrina Pastacaldi ◽  
Andrea Bonacchi ◽  
...  

Hepatic stellate cells (HSC) coordinate the liver wound-healing response through secretion of several cytokines and chemokines, including CCL2 (formerly known as monocyte chemoattractant protein-1). In this study, we evaluated the role of different proteins of the MAPK family (ERK, p38MAPK, and JNK) in the regulation of CCL2 expression by HSC, as an index of their proinflammatory activity. Several mediators activated all three MAPK, including TNF, IL-1, and PDGF. To assess the relative role of the different MAPKs, specific pharmacological inhibitors were used; namely, SB203580 (p38MAPK), SP600125 (JNK), and PD98059 (MEK/ERK). The efficacy and specificity of the different inhibitors in our cellular system were verified analyzing the enzymatic activity of the different MAPKs using in vitro kinase assays and/or testing the inhibition of phosphorylation of downstream substrates. SB203580 and SP600125 dose-dependently inhibited CCL2 secretion and gene expression induced by IL-1 or TNF. In contrast, inhibition of ERK did not affect the upregulation of CCL2 induced by the two cytokines. Finally, activin A was also found to stimulate CCL2 expression and to activate ERK, JNK, p38, and their downstream targets. Unlike in cells exposed to proinflammatory cytokines, all three MAPKs were required to induce CCL2 secretion in response to activin. We conclude that members of the MAPK family differentially regulate cytokine-induced chemokine expression in human HSC.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Xi Zhou ◽  
Li Yu ◽  
Min Zhou ◽  
Pengfei Hou ◽  
Long Yi ◽  
...  

Abstract Background This study investigated the mechanisms underlying the preventive effect of dihydromyricetin (DHM) against liver fibrosis involving hepatic stellate cells (HSCs) and hepatic natural killer (NK) cells. Methods A carbon tetrachloride (CCl4)-induced liver fibrosis model was established in C57BL/6 mice to study the antifibrotic effect of DHM based on serum biochemical parameters, histological and immunofluorescence stainings, and the expression of several fibrosis-related markers. Based on the immunoregulatory role of DHM, the effect of DHM on NK cell activation ex vivo was evaluated by flow cytometry. Then, we investigated whether DHM-induced autophagy was involved in HSCs inactivation using enzyme-linked immunosorbent assays, transmission electron microscopy, and western blot analysis. Thereafter, the role of DHM in NK cell-mediated killing was studied by in vitro coculture of NK cells and HSCs, with subsequent analysis by flow cytometry. Finally, the mechanism by which DHM regulates NK cells was studied by western blot analysis. Results DHM ameliorated liver fibrosis in C57BL/6 mice, as characterized by decreased serum alanine transaminase and aspartate transaminase levels, decreased expressions of collagen I alpha 1 (CoL-1α1), collagen I alpha 2 (CoL-1α2), tissue inhibitor of metalloproteinases 1 (TIMP-1), α-smooth muscle actin (α-SMA) and desmin, as well as increased expression of matrix metalloproteinase 1 (MMP1). Interestingly, HSCs activation was significantly inhibited by DHM in vivo and in vitro. As expected, DHM also upregulated autophagy-related indicators in liver from CCl4-treated mice. DHM also prevented TGF-β1-induced activation of HSCs in vitro by initiating autophagic flux. In contrast, the autophagy inhibitor 3-methyladenine markedly abolished the antifibrotic effect of DHM. Surprisingly, the frequency of activated intrahepatic NK cells was significantly elevated by DHM ex vivo. Furthermore, DHM enhanced NK cell-mediated killing of HSCs by increasing IFN-γ expression, which was abolished by an anti-IFN-γ neutralizing antibody. Mechanistically, DHM-induced IFN-γ expression was through AhR-NF-κB/STAT3 pathway in NK cells. Conclusion These results demonstrated that DHM can ameliorate the progression of liver fibrosis and inhibition of HSCs activation by inducing autophagy and enhancing NK cell-mediated killing through the AhR-NF-κB/STAT3-IFN-γ signaling pathway, providing new insights into the preventive role of DHM in liver fibrosis.


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