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Updated: May 5, 2026
Mouse Model of Metabolic Dysfunction-Associated Steatotic Liver Disease with Fibrosis
Published on: July 18, 2025
Mixed lineage kinase 3 deficient mice are protected against the high fat high carbohydrate diet-induced
Samar H Ibrahim1, Gregory J Gores, Petra Hirsova
1Division of Pediatric Gastroenterology and Hepatology Mayo Clinic, College of Medicine, Rochester, MN, USA.
Background & Aims:
C-Jun N-terminal kinase (JNK) activation is pivotal in the development of nonalcoholic steatohepatitis (NASH). Mixed lineage kinase 3 (MLK) 3 is one of the mitogen activated protein kinase kinase kinase (MAP3K) that mediates JNK activation in the liver. Despite this concept, the role of MLK3 in modulating liver injury during nutrient excess has not been explored. Our aim was to determine if MLK3 deficient mice were protected against high fat high carbohydrate (HFHC) diet-induced NASH.
Methods:
We employed eight-week-old Mlk3(-/-) male C57BL/6J mice, and wild type (WT) mice C57BL/6J as controls. Mice were fed a HFHC or a chow diet adlib for 16 weeks.
Results:
Hepatic JNK activating phosphorylation was readily absent in the Mlk3(-/-) mice fed the HFHC diet, but not in WT mice. This inhibition of JNK activation was hepatoprotective. Despite a comparable increase in weight gain, hepatic steatosis by histological examination and hepatic triglyceride quantification was reduced in HFHC diet-fed Mlk3(-/-) mice compared with WT mice. In addition, compared with the WT mice, HFHC diet-fed Mlk3(-/-) mice had significantly attenuated liver injury as manifested by reduced ALT levels, hepatocyte apoptosis, markers of hepatic inflammation and indices of hepatic fibrogenesis.
Conclusion:
Our results suggest that loss of MLK3 in mice is protective against HFHC diet-induced NASH, in a weight-independent fashion, through attenuation of JNK activation. MLK3 is a potential therapeutic target for the treatment of human NASH.
Insights
Mice lacking Mixed lineage kinase 3 (MLK3) show protection against nonalcoholic steatohepatitis (NASH) induced by a high-fat, high-carbohydrate diet. This protection occurs by reducing C-Jun N-terminal kinase (JNK) activation, suggesting MLK3 as a therapeutic target for NASH.
Area of Science:
- Hepatology
- Molecular Biology
- Metabolic Diseases
Background:
- C-Jun N-terminal kinase (JNK) activation is crucial in nonalcoholic steatohepatitis (NASH) development.
- Mixed lineage kinase 3 (MLK3), a MAP3K, mediates JNK activation in the liver.
- The specific role of MLK3 in diet-induced liver injury remains unexplored.
Purpose of the Study:
- To investigate the protective effects of MLK3 deficiency against high-fat, high-carbohydrate (HFHC) diet-induced NASH in mice.
- To determine if MLK3 modulates liver injury in response to nutrient excess.
Main Methods:
- Utilized MLK3-deficient (Mlk3(-/-)) and wild-type (WT) male C57BL/6J mice.
- Mice were fed either a HFHC diet or a standard chow diet for 16 weeks.
- Assessed liver injury markers, steatosis, inflammation, apoptosis, and fibrogenesis.
Main Results:
- MLK3 deficiency abolished JNK activation in mice fed the HFHC diet.
- HFHC diet-fed Mlk3(-/-) mice exhibited reduced hepatic steatosis and triglyceride levels compared to WT mice.
- Mlk3(-/-) mice showed significantly attenuated liver injury, including lower ALT levels, reduced hepatocyte apoptosis, inflammation, and fibrogenesis.
Conclusions:
- Loss of MLK3 confers protection against HFHC diet-induced NASH in a weight-independent manner.
- This protection is mediated through the attenuation of JNK activation.
- MLK3 represents a potential therapeutic target for treating human NASH.
