Osteopontin promotes rat hepatocyte proliferation both in vitro and in vivo

Abstract

Aim

This study aimed to examine the effects of osteopontin (OPN) on hepatocyte growth and liver regeneration (LR).

Methods

A recombinant lentivirus expressing OPN and OPN-siRNAs were used to treat BRL-3A cells, while the adenovirus expressing OPN or OPN-targeted shRNA were applied for rat primary hepatocytes. Moreover, rrOPN and OPN-Ab were added to treat BRL-3A. Next, rrOPN was administrated into rat regenerating livers. Then in vitro and in vivo assays were performed to evaluate the biological function of OPN in hepatocyte growth and LR.

Results

OPN overexpression facilitated proliferation and viability of BRL-3A cells and primary hepatocytes, while OPN silencing reversed these effects. Similarly, rrOPN stimulated cell cycle progression and viability, but OPN-Ab led to cell cycle arrest and decreased viability. OPN overexpression induced the expression of p-STAT3, p-AKT and CCND1, and OPN siRNA led to reduction of p-AKT and CCND1. Furthermore, rrOPN promoted the expression of p-STAT3 and p-AKT, while OPN-Ab and PI3K/Akt inhibitor LY294002 both inhibited the expressions of p-AKT and Bcl2. Moreover, LR rate, serum IL-6 and TNF-α, Ki-67⁺ proportion and the phosphorylation of STAT3, AKT and p65 were augmented by rrOPN treatment.

Conclusion

OPN promotes hepatocyte proliferation both in vitro and in vivo through STAT3 and AKT signaling pathways.

Keywords:

• Osteopontin
• BRL-3A
• primary hepatocyte
• hepatocyte proliferation
• liver regeneration

Ethics statement

All experiments complied with the guidelines for the care and use of experimental animals of the Ministry of Science of the People’s Republic of China.

Author contributions

Conceptualization, Gaiping Wang; Investigation, Peipei Chu; Methodology, Peipei Chu, Meng Chen and Shasha Chen; Resources, Xiaofang Li and Shasha Chen; Software, Liya Cheng and Ganggang Yang; Supervision, Cuifang Chang; Writing-original draft, Gaiping Wang; Writing-review & editing, Congcong Zhao.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by the National Natural Science Foundation of China [No.81200317], Henan Scientific and Technological Research Project [No.182102310244], Natural Science Foundation of Henan [No.182300410335], Key Scientific Research Projects of Henan Higher Education [No.18A180019] and Henan Normal University’s Crossing Research Project [No.20170008] with Xinxiang Giant Industry and Trade Co, Ltd.