LECT2 Deficiency Aggravates Cholestatic Liver Injury by Reprogramming Bile Acid Metabolism and Gut Microbiota
Background
Cholestatic liver injury is a severe condition characterized by impaired bile acid (BA) formation or flow, leading to toxic accumulation of BAs in the liver. This can result in progressive liver damage, fibrosis, and ultimately liver failure. Current treatments often fall short, highlighting the need for a deeper understanding of the underlying mechanisms. Leukocyte cell-derived chemotaxin 2 (LECT2) is a hepatokine implicated in various metabolic disorders, but its specific role in the complex interplay of BA metabolism and the gut-liver axis during cholestasis has remained largely unexplored.
Study Design
Researchers established an intrahepatic cholestasis model by administering ANIT to wild-type (WT) and LECT2 knockout (KO) mice. To investigate the role of BA metabolism and the gut-liver axis, they performed comprehensive metabolomics and metagenomics analyses. Specific interventions in KO mice included HDCA supplementation to restore alternative BA synthesis, fecal microbiota transplantation (FMT) to reshape gut microbiota, and antibiotic cocktail treatment to suppress intestinal FXR signaling. Additionally, clinical samples were analyzed to correlate LECT2 levels with markers of cholestasis in humans.
Results
LECT2 deletion was associated with altered BA synthesis, characterized by a significant shift toward the classical pathway, marked by upregulation of CYP7A1 and CYP8B1. Under cholestatic conditions induced by ANIT, LECT2 deficiency led to aggravated liver injury. This worsening was accompanied by profound alterations in gut microbiota composition, changes in intestinal FXR-FGF15 signaling, and increased hepatic JNK activation. These findings suggest a multi-faceted role for LECT2 in modulating the gut-liver axis. Importantly, targeted interventions in KO mice demonstrated therapeutic potential: > HDCA supplementation restored the alternative synthesis pathway, FMT reshaped gut microbiota, and antibiotic cocktail treatment suppressed intestinal FXR signaling, each of which was associated with improved cholestatic liver injury. In human clinical samples, LECT2 levels were negatively correlated with markers of cholestasis, further supporting its relevance to disease severity.
Key Findings
- LECT2 deficiency altered bile acid synthesis, shifting towards the classical pathway with upregulation of
CYP7A1andCYP8B1. - LECT2 deletion aggravated cholestatic liver injury, accompanied by gut microbiota dysbiosis and increased hepatic
JNKactivation. HDCAsupplementation restored alternative bile acid synthesis and improved liver injury in LECT2 KO mice.FMTreshaped gut microbiota and improved cholestatic liver injury in LECT2 KO mice.- Clinical LECT2 levels were negatively correlated with cholestasis markers, suggesting human relevance.
Why It Matters
Understanding LECT2's role in bile acid metabolism and gut-liver axis regulation opens new avenues for managing cholestatic liver injury. This research suggests that LECT2 deficiency contributes to disease progression, implying that strategies to maintain or enhance LECT2 function could be protective. Furthermore, the study highlights potential therapeutic targets, such as modulating bile acid synthesis pathways (e.g., via HDCA supplementation), restoring gut microbiota balance (e.g., via FMT), or intervening in the intestinal FXR-hepatic JNK signaling axis. For biohackers and clinicians, this points to the potential for future protocols that might involve dietary or microbial interventions to support bile acid homeostasis and mitigate liver damage in cholestatic conditions, moving beyond current standard-of-care limitations.
lect2
cholestasis
liver-injury
bile-acid-metabolism
gut-microbiota
fxr