Cross-talk between PPARγ, NF-κB, and p38 MAPK signaling mediates the ameliorating effects of bergenin against the iron overload-induced hepatotoxicity

Abstract

Hepatotoxicity is a serious health problem that associates the iron overload diseases such as thalassemia and sickle cell anemia. Induction of oxidative tissue injury and inflammation largely contributes to the iron-induced hepatotoxicity. The current study investigated the hepatoprotective potential of bergenin against the iron overload-associated hepatotoxicity. Male Wistar rats were treated with 30 mg/kg iron-dextran every other day over a ten-day period to establish an iron overload model. Bergenin was given in 80 mg/kg/day over the ten-day experimental period. Liver and blood specimens were then collected and subjected to various biochemical, histopathological, and molecular analyses. The results indicated that bergenin significantly decreased hepatic iron content and improved the hepatocellular integrity as demonstrated by reduced activity of the intracellular liver enzymes in the sera of the iron-intoxicated rats and alleviation of the iron-induced histopathological anomalies. Additionally, it alleviated the iron-induced oxidative tissue injury and improved the antioxidant potential of the liver tissue as reflected by decreased DNA oxidative damage and lipid peroxidation along with improved activity of the antioxidant enzymes. Equally important, bergenin attenuated the iron-evoked inflammation as indicated by down-regulation of the tumor necrosis factor alpha, interleukin-1 beta, myeloperoxidase, and cyclooxygenase-2. Mechanistically, bergenin suppressed the iron-induced nuclear translocation of the inflammatory transcription factor nuclear factor kappa B and phosphorylation of the inflammatory protein p38 mitogen-activated protein kinase. Interestingly, bergenin enhanced expression of the antioxidant and anti-inflammatory protein peroxisome proliferator-activated receptor gamma in the iron-intoxicated rats. Collectively, the presented study highlights the attenuating activity of bergenin on the iron-evoked hepatocellular injury and inflammation that is potentially mediated through targeting p38 mitogen-activated protein kinase and nuclear factor kappa B signaling as well as peroxisome proliferator-activated receptor gamma protein expression.

Keywords: Bergenin; Hepatotoxicity; Iron overload; Mitogen-activated protein kinase signaling; Peroxisome proliferator-activated receptor gamma.