Cargando…
Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings
Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are emerging worldwide epidemics, projected to become the leading cause of liver transplants. The strongest genetic risk factor for NAFLD/NASH susceptibility and progression is a single-nucleotide polymorphism (SNP) i...
Autores principales: | , , , , , , , , , , , , , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
MDPI
2020
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7600576/ https://www.ncbi.nlm.nih.gov/pubmed/33036387 http://dx.doi.org/10.3390/cells9102247 |
_version_ | 1783603179483561984 |
---|---|
author | Schwartz, Brian E. Rajagopal, Vaishnavi Smith, Cynthia Cohick, Evan Whissell, Gavin Gamboa, Mario Pai, Rutuja Sigova, Alla Grossman, Iris Bumcrot, David Sasidharan, Kavitha Romeo, Stefano Sehgal, Alfica Pingitore, Piero |
author_facet | Schwartz, Brian E. Rajagopal, Vaishnavi Smith, Cynthia Cohick, Evan Whissell, Gavin Gamboa, Mario Pai, Rutuja Sigova, Alla Grossman, Iris Bumcrot, David Sasidharan, Kavitha Romeo, Stefano Sehgal, Alfica Pingitore, Piero |
author_sort | Schwartz, Brian E. |
collection | PubMed |
description | Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are emerging worldwide epidemics, projected to become the leading cause of liver transplants. The strongest genetic risk factor for NAFLD/NASH susceptibility and progression is a single-nucleotide polymorphism (SNP) in the patatin-like phospholipase domain-containing 3 gene (PNPLA3), rs738409, encoding the missense mutation I148M. This aminoacidic substitution interferes with the normal remodeling of lipid droplets in hepatocytes. It is also thought to play a key role in promoting liver fibrosis by inhibiting the release of retinol from hepatic stellate cells. Reducing PNPLA3 levels in individuals homozygous for 148M may be an effective treatment for the entire spectrum of NAFLD, based on gene dosage analysis in the human population, as well as the protective effect of another naturally occurring SNP (rs2294918) in PNPLA3 which, when co-inherited, reduces PNPLA3 mRNA levels to 50% and counteracts disease risk. By screening a clinical compound library targeting specific signaling pathways active in primary human hepatocytes, we identified momelotinib, a drug evaluated in clinical trials to treat myelofibrosis, as a potent down-regulator of PNPLA3 expression, across all genotypes. We found that momelotinib treatment yielded >80% reduction in PNPLA3 mRNA in human primary hepatocytes and stellate cells, as well as in vivo via acute and chronic treatment of WT mice. Using a human multilineage 3D spheroid model of NASH homozygous for the PNPLA3 mutant protein, we additionally show that it decreases PNPLA3 mRNA as well as intracellular lipid content. Furthermore, we show that the effects on PNPLA3 coincide with changes in chromatin accessibility within regulatory regions of the PNPLA3 locus, consistent with inhibition occurring at the level of transcription. In addition to its primary reported targets, the JAK kinases, momelotinib inhibits several non-JAK kinases, including ACVR1. Using a combination of targeted siRNA knockdowns and signaling pathway perturbations, we show that momelotinib reduces the expression of the PNPLA3 gene largely through the inhibition of BMP signaling rather than the JAK/STAT pathway. Overall, our work identified momelotinib as a potential NASH therapeutic and uncovered previously unrecognized connections between signaling pathways and PNPLA3. These pathways may be exploited by drug modalities to “tune down” the level of gene expression, and therefore offer a potential therapeutic benefit to a high at-risk subset of NAFLD/NASH patients. |
format | Online Article Text |
id | pubmed-7600576 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2020 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-76005762020-11-01 Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings Schwartz, Brian E. Rajagopal, Vaishnavi Smith, Cynthia Cohick, Evan Whissell, Gavin Gamboa, Mario Pai, Rutuja Sigova, Alla Grossman, Iris Bumcrot, David Sasidharan, Kavitha Romeo, Stefano Sehgal, Alfica Pingitore, Piero Cells Article Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are emerging worldwide epidemics, projected to become the leading cause of liver transplants. The strongest genetic risk factor for NAFLD/NASH susceptibility and progression is a single-nucleotide polymorphism (SNP) in the patatin-like phospholipase domain-containing 3 gene (PNPLA3), rs738409, encoding the missense mutation I148M. This aminoacidic substitution interferes with the normal remodeling of lipid droplets in hepatocytes. It is also thought to play a key role in promoting liver fibrosis by inhibiting the release of retinol from hepatic stellate cells. Reducing PNPLA3 levels in individuals homozygous for 148M may be an effective treatment for the entire spectrum of NAFLD, based on gene dosage analysis in the human population, as well as the protective effect of another naturally occurring SNP (rs2294918) in PNPLA3 which, when co-inherited, reduces PNPLA3 mRNA levels to 50% and counteracts disease risk. By screening a clinical compound library targeting specific signaling pathways active in primary human hepatocytes, we identified momelotinib, a drug evaluated in clinical trials to treat myelofibrosis, as a potent down-regulator of PNPLA3 expression, across all genotypes. We found that momelotinib treatment yielded >80% reduction in PNPLA3 mRNA in human primary hepatocytes and stellate cells, as well as in vivo via acute and chronic treatment of WT mice. Using a human multilineage 3D spheroid model of NASH homozygous for the PNPLA3 mutant protein, we additionally show that it decreases PNPLA3 mRNA as well as intracellular lipid content. Furthermore, we show that the effects on PNPLA3 coincide with changes in chromatin accessibility within regulatory regions of the PNPLA3 locus, consistent with inhibition occurring at the level of transcription. In addition to its primary reported targets, the JAK kinases, momelotinib inhibits several non-JAK kinases, including ACVR1. Using a combination of targeted siRNA knockdowns and signaling pathway perturbations, we show that momelotinib reduces the expression of the PNPLA3 gene largely through the inhibition of BMP signaling rather than the JAK/STAT pathway. Overall, our work identified momelotinib as a potential NASH therapeutic and uncovered previously unrecognized connections between signaling pathways and PNPLA3. These pathways may be exploited by drug modalities to “tune down” the level of gene expression, and therefore offer a potential therapeutic benefit to a high at-risk subset of NAFLD/NASH patients. MDPI 2020-10-07 /pmc/articles/PMC7600576/ /pubmed/33036387 http://dx.doi.org/10.3390/cells9102247 Text en © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Schwartz, Brian E. Rajagopal, Vaishnavi Smith, Cynthia Cohick, Evan Whissell, Gavin Gamboa, Mario Pai, Rutuja Sigova, Alla Grossman, Iris Bumcrot, David Sasidharan, Kavitha Romeo, Stefano Sehgal, Alfica Pingitore, Piero Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings |
title | Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings |
title_full | Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings |
title_fullStr | Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings |
title_full_unstemmed | Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings |
title_short | Discovery and Targeting of the Signaling Controls of PNPLA3 to Effectively Reduce Transcription, Expression, and Function in Pre-Clinical NAFLD/NASH Settings |
title_sort | discovery and targeting of the signaling controls of pnpla3 to effectively reduce transcription, expression, and function in pre-clinical nafld/nash settings |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7600576/ https://www.ncbi.nlm.nih.gov/pubmed/33036387 http://dx.doi.org/10.3390/cells9102247 |
work_keys_str_mv | AT schwartzbriane discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT rajagopalvaishnavi discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT smithcynthia discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT cohickevan discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT whissellgavin discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT gamboamario discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT pairutuja discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT sigovaalla discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT grossmaniris discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT bumcrotdavid discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT sasidharankavitha discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT romeostefano discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT sehgalalfica discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings AT pingitorepiero discoveryandtargetingofthesignalingcontrolsofpnpla3toeffectivelyreducetranscriptionexpressionandfunctioninpreclinicalnafldnashsettings |