Morin counteracts KBrO3-induced hepatotoxicity by reprogramming the HOTAIR/MEG3-miR-125b-5p/miR-214-5p axis and suppressing STAT1-associated RIPK3/MLKL necroptotic signaling.

Abstract

Potassium bromate (KBrO₃; PB), an oxidative contaminant in ozonated water and bakery products, induces multi-mechanistic hepatotoxicity. Its epigenetic, necroptotic, and metabolic injury dimensions remain poorly characterized. Morin (MOR), a dietary flavonoid with established antioxidant and anti-inflammatory properties, has not previously been evaluated against PB-induced subacute hepatotoxicity. To characterize MOR's hepatoprotective mechanisms against PB-induced liver injury, focusing on the HOTAIR/MEG3-miRNA epigenetic axis, STAT1-associated RIPK3/MLKL necroptotic signaling, and Glut2/HPGD-AKT/mTOR metabolic signaling. Male Sprague-Dawley rats (n = 28) were assigned to Control, MOR (100 mg/kg), PB (62 mg/kg), and PB + MOR groups for 14 days. Outcomes included hepatobiliary biochemistry, oxidative stress markers, inflammatory mediators (ELISA), lncRNA/miRNA/mRNA profiling (RT-qPCR), immunohistochemistry (RIPK3, MLKL), double immunofluorescence (Glut2/AKT1; HPGD/mTOR), histopathology, and PCA. PB produced marked redox imbalance (↑MDA; ↓SOD, CAT, GPx), NF-κB/NLRP3-associated inflammatory mediator elevation, epigenetic disruption (↑HOTAIR, ↓MEG3; ↑miR-125b-5p/↓BCL2L2; ↓miR-214-5p/↑SMAD4), upregulation of STAT1-associated necroptosis-related transcripts and proteins (↑RIPK1/RIPK3/MLKL), and metabolic dysfunction (↓Glut2, ↓HPGD; ↑AKT1/mTOR). MOR restored redox balance, suppressed inflammation, and reprogrammed the miRNA axis while normalizing MLKL (transcript and immunohistochemistry) and AKT1 and partially attenuating RIPK3, mTOR, and STAT1. MOR confers multi-targeted hepatoprotection by restoring redox and metabolic homeostasis, attenuating NF-κB/NLRP3-associated inflammation, reprogramming HOTAIR/MEG3-miRNA epigenetics, and attenuating STAT1-associated RIPK3/MLKL signaling, supporting its potential as a dietary hepatoprotective candidate. PB is associated with engagement of the hepatic STAT1/RIPK3/MLKL axis and disrupts the HOTAIR/MEG3-miRNA network-both previously undocumented for this toxicant. MOR partially restores miR-214-5p/miR-466 expression while suppressing their downstream effector SMAD4, consistent with attenuation of pro-fibrotic signaling. Future work should employ multi-dose designs, in vitro mechanistic dissection, sex-stratified analyses, and clinical pharmacokinetic profiling to advance MOR toward translational application.