ADSCs-derived exosomes ameliorate hepatic fibrosis by suppressing stellate cell activation and remodeling hepatocellular glutamine synthetase-mediated glutamine and ammonia homeostasis

Abstract

Background Hepatic fibrosis is a common pathologic stage in chronic liver disease development, which might ultimately lead to liver cirrhosis. Accumulating evidence suggests that adipose-derived stromal cells (ADSCs)-based therapies show excellent therapeutic potential in liver injury disease owing to its superior properties, including tissue repair ability and immunomodulation effect. However, cell-based therapy still limits to several problems, such as engraftment efficiency and immunoreaction, which impede the ADSCs-based therapeutics development. So, ADSCs-derived extracellular vesicles (EVs), especially for exosomes (ADSC-EXO), emerge as a promise cell-free therapeutics to ameliorate liver fibrosis. The effect and underlying mechanisms of ADSC-EXO in liver fibrosis remains blurred. Methods Hepatic fibrosis murine model was established by intraperitoneal sequential injecting the diethylnitrosamine (DEN) for two weeks and then carbon tetrachloride (CCl4) for six weeks. Subsequently, hepatic fibrosis mice were administrated with ADSC-EXO (10 μg/g) or PBS through tail vein infusion for three times in two weeks. To evaluate the anti-fibrotic capacity of ADSC-EXO, we detected liver morphology by histopathological examination, ECM deposition by serology test and Sirius Red staining, profibrogenic markers by qRT-PCR assay. LX-2 cells treated with TGF-β (10 ng/ml) for 12 h were conducted for evaluating ADSC-EXO effect on activated hepatic stellate cells (HSCs). RNA-seq was performed for further analysis of the underlying regulatory mechanisms of ADSC-EXO in liver fibrosis. Results In this study, we obtained isolated ADSCs, collected and separated ADSCs-derived exosomes. We found that ADSC-EXO treatment could efficiently ameliorate DEN/CCl4-induced hepatic fibrosis by improving mice liver function and lessening hepatic ECM deposition. Moreover, ADSC-EXO intervention could reverse profibrogenic phenotypes both in vivo and in vitro, including HSCs activation depressed and profibrogenic markers inhibition. Additionally, RNA-seq analysis further determined that decreased glutamine synthetase (Glul) of perivenous hepatocytes in hepatic fibrosis mice could be dramatically up-regulated by ADSC-EXO treatment; meanwhile, glutamine and ammonia metabolism-associated key enzyme OAT was up-regulated and GLS2 was down-regulated by ADSC-EXO treatment in mice liver. In addition, glutamine synthetase inhibitor would erase ADSC-EXO therapeutic effect on hepatic fibrosis. Conclusions These findings demonstrated that ADSC-derived exosomes could efficiently alleviate hepatic fibrosis by suppressing HSCs activation and remodeling glutamine and ammonia metabolism mediated by hepatocellular glutamine synthetase, which might be a novel and promising anti-fibrotic therapeutics for hepatic fibrosis disease.

TNF-α/IL-1β-licensed hADSCs alleviate cholestatic liver injury and fibrosis in mice via COX-2/PGE2 pathway

“…The broken balance between extracellular matrix (ECM) degradation and deposition promoted the initiation of liver fibrosis [ 55 , 56 ]. It has been proven that hADSCs contribute to preventing or even eliminating further liver fibrogenesis by downregulating the expressions of inflammatory genes and inhibiting the activation of HSCs [ 18 – 20 , 57 , 58 ]. Consistently, our present data reveal that hADSC infusion ameliorated the pathological presentation of BDL-induced liver injury.…”

“…By virtue of their immunomodulatory capacities, endogenous tissue repair potential, and other unique properties, ADSCs have been extensively utilized for the treatment of diverse diseases [ 14 – 17 ]. Previous studies have shown that ADSC transplantation could constitute an alternative therapeutic approach to combating or ameliorating hepatic disease owing to their positive effects on the modulation of inflammation and the alleviation of fibrosis formation [ 18 – 20 ]. Unfortunately, the survival crisis that mesenchymal stem cells (MSCs) inevitably suffer upon being transplanted into the host remains a major obstacle to translational success [ 21 , 22 ].…”

Adipose‐Derived Mesenchymal Stem Cell‐Derived Exosomes Biopotentiated Extracellular Matrix Hydrogels Accelerate Diabetic Wound Healing and Skin Regeneration

“…Isolation and Identification of ADSC-Derived Exosomes: ADSC-exos were isolated from cell supernatants as described previously [56,57] When ADSCs reached 80−90% confluence, the FBS-free culture medium was changed. The culture supernatant at 3000 X g was centrifuged for 30 min to remove dead cells, followed by centrifugation at 10 000 X g for 30 min to eliminate cellular debris.…”

Exosomes in liver fibrosis: The role of modulating hepatic stellate cells and immune cells, and prospects for clinical applications

“…Notably, ADSC-EXO may reverse the pro-fibrotic phenotype in vivo and in vitro . Upon more in-depth study, they concluded that ADSC-EXO improve LF by inhibiting HSC activation and remodeling hepatocyte glutamine synthetase-mediated glutamine and ammonia homeostasis ( 80 ). In addition, umbilical cord plasma-derived exosomes (UCB-EXO) may be a promising therapy for LF.…”