The effect of function in mesenchymal stem cells after bilirubin stimulation

Objective: Neonatal bilirubin encephalopathy is a serious complication of neonatal hyperbilirubinemia. There is no good treatment for its. At present, human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) therapy has been widely concerned, but its effect on bilirubin encephalopathy is not clear. Therefore, this study intends to explore the stimulation of hUC-MSCs by bilirubin in vitro, and provide theoretical basis for the further treatment of bilirubin encephalopathy with MSCs. Methods hUC-MSCs were added in control group (0mg/dL group), and bilirubin concentration group(5 mg/dL, 10 mg/dL and 15 mg/dL) for 12h and 24h. The survival rate after bilirubin stimulation was detected by CCK-8, the adipogenic and osteogenic differentiation was induced to observe the change of differentiation ability, IL-6, TSG-6 level was measured by ELISA, Western boltting measured Bax Bcl-2 caspase 3 protein level. Results The number of cells decreased and the morphology did not change significantly. The cell survival rate of each group was statistically significant 12h after bilirubin stimulation (P < 0.001). After induction, there was no significant difference in staining results among all groups. This indicated that bilirubin had no significant effect on the osteogenic adipogenic differentiation of hUC-MSCs.The level of IL-6, TSG-6, Bax, Bcl-2 and capcase-3 increased significantly after bilirubin stimulated MSCs compared with the control group (P < 0.05). Conclusion Bilirubin have toxic effects for hUC-MSCs, with the increase of bilirubin concentration will affect the proliferation secretion and apoptosis, but it had no obvious effect on their differentiation ability.