Inhibin βE (INHBE) is a possible insulin resistance-associated hepatokine identified by comprehensive gene expression analysis in human liver biopsy samples

PLoS One. 2018 Mar 29;13(3):e0194798. doi: 10.1371/journal.pone.0194798. eCollection 2018.

Abstract

The liver plays a major role in whole-body energy homeostasis by releasing secretory factors, termed hepatokines. To identify novel target genes associated with insulin resistance, we performed a comprehensive analysis of gene expression profiles using a DNA chip method in liver biopsy samples from humans with varying degrees of insulin resistance. Inhibin βE (INHBE) was identified as a novel putative hepatokine with hepatic gene expression that positively correlated with insulin resistance and body mass index in humans. Quantitative real time-PCR analysis also showed an increase in INHBE gene expression in independent liver samples from insulin-resistant human subjects. Additionally, Inhbe gene expression increased in the livers of db/db mice, a rodent model of type 2 diabetes. To preliminarily screen the role of Inhbe in vivo in whole-body energy metabolic status, hepatic mRNA was knocked down with siRNA for Inhbe (siINHBE) in db/db mice. Treatment with siINHBE suppressed body weight gain during the two-week experimental period, which was attributable to diminished fat rather than lean mass. Additionally, treatment with siINHBE decreased the respiratory quotient and increased plasma total ketone bodies compared with treatment with non-targeting siRNA, both of which suggest enhanced whole-body fat utilization. Our study suggests that INHBE functions as a possible hepatokine to alter the whole-body metabolic status under obese insulin-resistant conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipose Tissue / cytology
  • Animals
  • Biopsy
  • Body Weight
  • Female
  • Gene Expression Profiling*
  • Humans
  • Inhibin-beta Subunits / deficiency
  • Inhibin-beta Subunits / genetics*
  • Inhibin-beta Subunits / metabolism
  • Insulin Resistance / genetics*
  • Liver / metabolism
  • Liver / pathology*
  • Male
  • Mice
  • Middle Aged
  • Phenotype
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • RNA, Small Interfering / genetics

Substances

  • INHBE protein, human
  • Inhbe protein, mouse
  • RNA, Messenger
  • RNA, Small Interfering
  • Inhibin-beta Subunits

Grants and funding

This work was supported by the Chugai Pharmaceutical Co., Ltd. The Chugai Pharmaceutical Co. Ltd. provided support in the form of salaries for authors MS, MA, Y. Kushima, KH, YS, and Y. Kawabe. TT received research grants from Chugai Pharmaceutical Co., Ltd. There are no products currently being developed or already in the market that are associated with this research. The funder provided support in the form of salaries for authors MS, MA, Y. Kushima, KH, YS, and Y. Kawabe as Chugai’s employees. The authors from the funder designed the study, collected the data and analyzed data for the animal studies. And these authors also contributed to analyze DNA chip and prepare the manuscript. The specific roles of these authors are shown in the ‘author contributions’ section.