Alleviation of Aflatoxin B1-Induced Hepatic Damage by Propolis: Effects on Inflammation, Apoptosis, and Cytochrome P450 Enzyme Expression

TL;DR

Propolis, a bee product, reduces liver damage caused by aflatoxin B1 by reducing inflammation, preventing cell death, and regulating liver enzymes.

Contribution

This study demonstrates propolis's protective effects against aflatoxin B1-induced liver injury through multiple biological pathways in rats.

Findings

Propolis supplementation restored Nrf2–HO-1 signaling and reduced inflammatory markers like IL-6 in AFB1-treated rats.

Propolis reversed AFB1-induced liver damage, including hydropic degeneration and increased apoptosis markers.

Propolis suppressed AFB1-induced upregulation of CYP1A2 and CYP3A4 enzymes.

Abstract

AflatoxinB1 (AFB1) is a hepatotoxic mycotoxin whose bioactivation by cytochrome P450 (CYP450) enzymes generates reactive metabolites that drive oxidative stress, inflammation, and apoptosis. Propolis is a bee-derived product with antioxidant and immunomodulatory properties. To investigate whether propolis supplementation attenuates AFB1-induced hepatic injury by modulating inflammatory mediators, Nrf2–HO-1 signaling, mitochondrial apoptosis, and CYP450 expression in rats, twenty-four male Sprague-Dawley rats were randomly allocated to four groups (n = 6): control, AFB1 (25 µg/kg/day), propolis (250 mg/kg/day), and AFB1 + propolis. Treatments were given by oral gavage for 28 days. Hepatic IL-1β, IL-6, TNF-α, Nrf2 and HO-1 levels were measured by ELISA. Histopathology was assessed on H&E-stained sections. Bax, Bcl-2, caspase-3, CYP1A2, CYP3A4, CYP2C19 and cytochrome P450 reductase expressions were evaluated immunohistochemically and quantified by ImageJ. Data were analyzed using one-way ANOVA with Tukey’s post hoc test. AFB1 significantly increased hepatic IL-1β and IL-6 and reduced Nrf2 levels, while propolis supplementation restored Nrf2, elevated HO-1 and significantly lowered IL-6 compared with AFB1 alone (p < 0.05). AFB1 induced marked hydropic degeneration, sinusoidal congestion, and mononuclear infiltration, alongside increased Bax and caspase-3 and decreased Bcl-2 expression; these changes were largely reversed in propolis-treated groups. AFB1 upregulated CYP1A2, CYP3A4 and cytochrome P450 reductase, whereas propolis co-treatment significantly suppressed their expression without affecting CYP2C19. Propolis supplementation attenuated AFB1-induced liver injury through coordinated anti-inflammatory, antioxidant, anti-apoptotic and metabolic regulatory effects, notably via restoration of Nrf2–HO-1 signaling and down-regulation of key CYP450 isoenzymes. Propolis may represent a promising natural dietary strategy against AFB1-associated hepatotoxicity, warranting further translational research.

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