Abstract
Background & Aims: Dysregulated glucose homeostasis and lipid accumulation characterize non-alcoholic fatty liver disease (NAFLD), but underlying mechanisms are obscure. We report here that Krüppel-like factor 6 (KLF6), a ubiquitous transcription factor that promotes adipocyte differentiation, also provokes the metabolic abnormalities of NAFLD by post-transcriptionally activating PPARα-signaling. Methods: Mice with either hepatocyte-specific depletion of KLF6 ('ΔHepKlf6') or global KLF6 heterozygosity (Klf6+/-) were fed a high fat diet (HFD) or chow for 8 or 16 weeks. Glucose and insulin tolerance tests were performed to assess insulin sensitivity. Overexpression and knockdown of KLF6 in cultured cells enabled the elucidation of underlying mechanisms. In liver samples from a cohort of 28 NAFLD patients, the expression of KLF6-related target genes was quantified. Results: Mice with global- or hepatocyte-depletion of KLF6 have reduced body fat content and improved glucose and insulin tolerance, and are protected from HFD-induced steatosis. In hepatocytes, KLF6 deficiency reduces PPARα-regulated genes (Trb3, Pepck) with diminished PPARα protein but no change in Pparα mRNA, which is explained by the discovery that KLF6 represses miRNA 10b, which leads to induction of PPARα. In NAFLD patients with advanced disease and inflammation, the expression of miRNA 10b is significantly downregulated, while PEPCK mRNA is upregulated; KLF6 mRNA expression also correlates with TRB3 as well as PEPCK gene expression. Conclusions: KLF6 increases PPARα activity, whereas KLF6 loss leads to PPARα repression and attenuation of lipid and glucose abnormalities associated with a high fat diet. The findings establish KLF6 as a novel regulator of hepatic glucose and lipid metabolism in fatty liver.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1000-1006 |
| Number of pages | 7 |
| Journal | Journal of Hepatology |
| Volume | 58 |
| Issue number | 5 |
| DOIs | |
| State | Published - May 2013 |
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Keywords
- CD36
- KLF6
- miRNA-10b
- NAFLD
- PEPCK
- PPARα
- TRB3
ASJC Scopus subject areas
- Hepatology
Cite this
Post-transcriptional activation of PPAR alpha by KLF6 in hepatic steatosis. / Bechmann, Lars P.; Vetter, Diana; Ishida, Junichi; Hannivoort, Rebekka A.; Lang, Ursula E.; Kocabayoglu, Peri; Fiel, M. Isabel; Muñoz, Ursula; Patman, Gillian L.; Ge, Fengxia; Yakar, Shoshana; Li, Xiaosong; Agius, Loranne; Lee, Young Min; Zhang, Weijia; Hui, Kei Yiu; Televantou, Despina; Schwartz, Gary J.; Leroith, Derek; Berk, Paul D.; Nagai, Ryozo; Suzuki, Toru; Reeves, Helen L.; Friedman, Scott L.
In: Journal of Hepatology, Vol. 58, No. 5, 05.2013, p. 1000-1006.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Post-transcriptional activation of PPAR alpha by KLF6 in hepatic steatosis
AU - Bechmann, Lars P.
AU - Vetter, Diana
AU - Ishida, Junichi
AU - Hannivoort, Rebekka A.
AU - Lang, Ursula E.
AU - Kocabayoglu, Peri
AU - Fiel, M. Isabel
AU - Muñoz, Ursula
AU - Patman, Gillian L.
AU - Ge, Fengxia
AU - Yakar, Shoshana
AU - Li, Xiaosong
AU - Agius, Loranne
AU - Lee, Young Min
AU - Zhang, Weijia
AU - Hui, Kei Yiu
AU - Televantou, Despina
AU - Schwartz, Gary J.
AU - Leroith, Derek
AU - Berk, Paul D.
AU - Nagai, Ryozo
AU - Suzuki, Toru
AU - Reeves, Helen L.
AU - Friedman, Scott L.
PY - 2013/5
Y1 - 2013/5
N2 - Background & Aims: Dysregulated glucose homeostasis and lipid accumulation characterize non-alcoholic fatty liver disease (NAFLD), but underlying mechanisms are obscure. We report here that Krüppel-like factor 6 (KLF6), a ubiquitous transcription factor that promotes adipocyte differentiation, also provokes the metabolic abnormalities of NAFLD by post-transcriptionally activating PPARα-signaling. Methods: Mice with either hepatocyte-specific depletion of KLF6 ('ΔHepKlf6') or global KLF6 heterozygosity (Klf6+/-) were fed a high fat diet (HFD) or chow for 8 or 16 weeks. Glucose and insulin tolerance tests were performed to assess insulin sensitivity. Overexpression and knockdown of KLF6 in cultured cells enabled the elucidation of underlying mechanisms. In liver samples from a cohort of 28 NAFLD patients, the expression of KLF6-related target genes was quantified. Results: Mice with global- or hepatocyte-depletion of KLF6 have reduced body fat content and improved glucose and insulin tolerance, and are protected from HFD-induced steatosis. In hepatocytes, KLF6 deficiency reduces PPARα-regulated genes (Trb3, Pepck) with diminished PPARα protein but no change in Pparα mRNA, which is explained by the discovery that KLF6 represses miRNA 10b, which leads to induction of PPARα. In NAFLD patients with advanced disease and inflammation, the expression of miRNA 10b is significantly downregulated, while PEPCK mRNA is upregulated; KLF6 mRNA expression also correlates with TRB3 as well as PEPCK gene expression. Conclusions: KLF6 increases PPARα activity, whereas KLF6 loss leads to PPARα repression and attenuation of lipid and glucose abnormalities associated with a high fat diet. The findings establish KLF6 as a novel regulator of hepatic glucose and lipid metabolism in fatty liver.
AB - Background & Aims: Dysregulated glucose homeostasis and lipid accumulation characterize non-alcoholic fatty liver disease (NAFLD), but underlying mechanisms are obscure. We report here that Krüppel-like factor 6 (KLF6), a ubiquitous transcription factor that promotes adipocyte differentiation, also provokes the metabolic abnormalities of NAFLD by post-transcriptionally activating PPARα-signaling. Methods: Mice with either hepatocyte-specific depletion of KLF6 ('ΔHepKlf6') or global KLF6 heterozygosity (Klf6+/-) were fed a high fat diet (HFD) or chow for 8 or 16 weeks. Glucose and insulin tolerance tests were performed to assess insulin sensitivity. Overexpression and knockdown of KLF6 in cultured cells enabled the elucidation of underlying mechanisms. In liver samples from a cohort of 28 NAFLD patients, the expression of KLF6-related target genes was quantified. Results: Mice with global- or hepatocyte-depletion of KLF6 have reduced body fat content and improved glucose and insulin tolerance, and are protected from HFD-induced steatosis. In hepatocytes, KLF6 deficiency reduces PPARα-regulated genes (Trb3, Pepck) with diminished PPARα protein but no change in Pparα mRNA, which is explained by the discovery that KLF6 represses miRNA 10b, which leads to induction of PPARα. In NAFLD patients with advanced disease and inflammation, the expression of miRNA 10b is significantly downregulated, while PEPCK mRNA is upregulated; KLF6 mRNA expression also correlates with TRB3 as well as PEPCK gene expression. Conclusions: KLF6 increases PPARα activity, whereas KLF6 loss leads to PPARα repression and attenuation of lipid and glucose abnormalities associated with a high fat diet. The findings establish KLF6 as a novel regulator of hepatic glucose and lipid metabolism in fatty liver.
KW - CD36
KW - KLF6
KW - miRNA-10b
KW - NAFLD
KW - PEPCK
KW - PPARα
KW - TRB3
UR - http://www.scopus.com/inward/record.url?scp=84876291629&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84876291629&partnerID=8YFLogxK
U2 - 10.1016/j.jhep.2013.01.020
DO - 10.1016/j.jhep.2013.01.020
M3 - Article
VL - 58
SP - 1000
EP - 1006
JO - Journal of Hepatology
JF - Journal of Hepatology
SN - 0168-8278
IS - 5
ER -