Published online Oct 26, 2021. doi: 10.4252/wjsc.v13.i10.1580
Peer-review started: April 13, 2021
First decision: May 12, 2021
Revised: May 25, 2021
Accepted: September 19, 2021
Article in press: September 19, 2021
Published online: October 26, 2021
End-stage liver disease (ESLD) causes extensive healthcare burden with limited treatment options. Cell-based therapies using mesenchymal stem cells (MSCs) emerged as a potential approach to support hepatic regeneration in ESLD. However, effective translation of this therapy requires MSCs to have maximum regenerative potential. In vitro preconditioning strategies have been employed to strengthen the regenerative and differentiation potential of MSCs. Chemical compounds of the class triterpenes; glycyrrhizic acid and 18β-glycyrrhetinic acid present diverse therapeutic features including hepato-protection and anti-fibrotic characteristics. They are capable of modulating several physiological pathways that are crucial in hepatic regeneration. Preconditioning with hepato-protective triterpenes may stimulate MSC fate transition towards hepatocytes.
Although mesenchymal stem cell-mediated therapy has proved as an effective approach for hepatic regeneration, the major challenge is low cell viability and resistance in the impaired tissue post-transplantation. To acquire a persistent therapeutic efficacy, in vitro preconditioning of MSCs with hepato-protective chemical compounds may facilitate their regenerative and differentiation potential towards hepatic lineage for better survival, homing, and migration ability at the site of injury.
Considering the characteristics of triterpenes, glycyrrhizic acid and 18β-glycyrrhetinic acid in hepatic anomalies, the objective of the study is to explore their role in hepatic differentiation of MSCs. Preconditioned cells may serve as a better source for tissue regeneration in liver injury.
hUC-MSCs were harvested and characterized phenotypically by flow cytometry and immunocytochemistry for the expression of MSC associated surface molecules. Isolated cells were treated with glycyrrhizic acid, 18β-glycyrrhetinic acid, and their combination for 24 h, and then analyzed at three time points; day 7, 14, and 21. qRT-PCR was performed to evaluate the expression of hepatic genes. On day 21, hepatic proteins were analyzed by immunocytochemistry. Periodic acid Schiff staining was performed to determine the functional ability of treated cells.
The transcriptional profile of preconditioned MSCs displayed significant expression of hepatic genes with increasing time of differentiation. Preconditioned cells showed positive protein expression of hepatocyte specific proteins. The results were further corroborated by positive periodic acid Schiff staining, indicating the presence of glycogen in their cytoplasm. Moreover, bi-nucleated cells which is the typical feature of hepatocytes, were also seen in the preconditioned cells.
Our data suggest that preconditioning of hUC-MSCs with triterpene compounds, glycyrrhizic acid, and 18β-glycyrrhetinic acid or both, successfully differentiates these cells into hepatic-like cells. The study would serve as an attempt to develop new targeted therapies using triterpenes in combination with stem cells for the treatment of end-stage liver diseases.
The present study is an endeavor to augment cell based therapeutic approach by preconditioning hUC-MSCs with glycyrrhizic acid and 18β-glycyrrhetinic acid to promote their therapeutic and differentiation potential towards hepatic lineage. The preconditioned MSCs may serve as an effective source for cell therapy for injured hepatic tissue in clinical applications.