Extracellular regulated protein kinases 1/2 phosphorylation is required for hepatic differentiation of human umbilical cord-derived mesenchymal stem cells

Abstract

Mesenchymal stem cells (MSCs) have the capacity to restore liver function by differentiating into hepatocyte like cells. However, the underlying mechanisms are not well understood. Here, we have investigated the signals involved in the hepatic differentiation of human umbilical cord-derived mesenchymal stem cells (hUCMSCs). hUCMSCs were treated with mouse fetal liver-conditioned medium (FLCM) to induce hepatic differentiation. Flow cytometry, reverse transcription PCR, real-time PCR, immunocytochemistry, and polymerase chain reaction (PCR) array were used to detect the expression of MSC-and hepotocyte-specific markers in FLCM-treated hUCMSCs. Urea production and cytochrome P450 3A4 (CYP3A4) activity were used as indicators to evaluate liver cell characteristics. Raf/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) was analyzed in hUCMSCs by Western blotting. Following FLCM treatment, expression of MSC-specific markers decreased, while hepatocytespecific gene expression was increased. Urea production, albumin secretion, glycogen storage, and CYP3A4 activity were significantly enhanced in FLCM-treated cells. In addition, ERK1/2 phosphorylation was increased in a time-dependent manner through Raf/MEK/ERK pathway, and phosphorylation was sustained at a high level during hepatic induction. Inhibition of ERK1/2 activation by U0126 (an ERK1/2 inhibitor) and pFLAG-CMV-ERK1(K71R) (negative mutant of ERK1) reversed the expression of liver-specific genes in hUCMSCs and affected hepatic function significantly. In summary, this work shows that ERK1/2 phosphorylation plays an important role in inducing hepatic differentiation of hUCMSCs in FLCM.

RICK regulates the odontogenic differentiation of dental pulp stem cells through activation of TNF‐α via the ERK and not through NF‐κB signaling pathway

“…RICK is able to regulate the downstream signal through the above pathways (Jeong et al, 2013; H. S. Kim et al, 2013). ERK1/2 phosphorylation is observed in the differentiation of MSCs to multiple lineages (Yan et al, 2015; Zhang et al, 2015). The ERK signaling pathway is involved in odontogenic differentiation of stem cells originating from the apical papilla (SCAPs) and exfoliated deciduous teeth (SHED; Liu et al, 2019; Mu et al, 2014).…”

Human umbilical cord mesenchymal stem cells ameliorate liver fibrosisin vitroandin vivo: From biological characteristics to therapeutic mechanisms

“…Conditioned medium: Previous findings have suggested that, under defined conditions ( e.g ., a simulated normal liver microenvironment), hUC-MSCs can differentiate into functional hepatocytes. Yan et al[74] explored the use of fetal liver-conditioned medium for hepatic differentiation of hUC-MSCs. The expression of MSC-specific markers decreased, while hepatocyte-specific gene expression was increased.…”

Mesenchymal Stem Cells and Their Small Extracellular Vesicles as Crucial Immunological Efficacy for Hepatic Diseases

“…Mesenchymal stem cells (MSCs) have gained attention for their potential in treating various diseases, advancing from animal experiments to clinical trials (1), and MSC biosafety has been widely indicated. We defined the renovation of MSCs in hepatic diseases over a decade ago using an in-house isolation culture system (2)(3)(4)(5)(6)(7). MSCs differentiate into hepatocyte-like cells (8), informing the transition from liver to hepatocyte transplantation to improve liver function.…”

“…The capacity of MSCs to reverse mouse hepatic injury (2) and Schistosoma japonicum-induced mouse liver injury was also shown (7). ERK1/2 phosphorylation was defined as an essential factor for differentiation (3), and concurrent overexpression of miR-106a, miR-574-3p, and miR-451 was shown to induce human umbilical cordderived MSC (hucMSC) differentiation into functionally mature hepatocytes (9).…”