Schisandrin B stimulates a cytoprotective response in rat liver exposed to mercuric chloride

Division of Human Anatomy, Department of Biomedical Sciences and Biotechnology, Viale Europa 11, 25123 Brescia, Italy.
Food and chemical toxicology: an international journal published for the British Industrial Biological Research Association (Impact Factor: 2.9). 09/2009; 47(11):2834-40. DOI: 10.1016/j.fct.2009.09.003
Source: PubMed


Mercury represents an ubiquitous environmental toxic metal. Heat shock proteins (HSP) and metallothioneins (MTs) help to protect cells against metal toxicity. Schisandrin B (Sch B), a lignoid from Schisandra chinensis, has been successfully used to treat hepatitis, but its effect against mercury hepatotoxicity remains unknown. We analyzed whether Sch B could protect rat liver against mercuric chloride (HgCl2) intake by analyzing stress proteins and histopathological changes. Wistar rats were administered Sch B (10mg/kg/day by gavage) or vehicle (olive oil) for 10 days. A subset of each group also received low-dose HgCl2 (0.1mg/kg/day) for 3 days on days 8-10. Another group received Sch B for 10 days with a single high dose of HgCl2 (1mg/kg intraperitoneally) on day 10. In rats treated with Sch B and HgCl2, HSP72, HSP25 and MTs were overexpressed in liver zones 1 and 3 irrespective of HgCl2 dosing schedules. Furthermore Sch B alone induced perinuclear rough endoplasmic reticulum alignment and if associated to HgCl2, increased mitochondrial density and dense bodies, all signs of intense detoxification machinery. Taking together these data suggest that dietary Sch B counteracts HgCl2 hepatotoxicity in the rat by stimulating chaperones responsible for anabolic activity.

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Available from: Alessandra Stacchiotti, Feb 23, 2015
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    • "However, the potential role of oxidative stress in MeHg-induced cell damage seems to suggest that antioxidants could be a useful tool to mitigate MeHg toxicity. Since many studies have demonstrated that heavy metals, such as Hg, induce oxidative stress (Cuello et al., 2010; de Melo Reis et al., 2007; Kaur et al., 2007; Li et al., 2012; Lu et al., 2011; Stacchiotti et al., 2009; Watanabe et al., 2009), the utility of antioxidants, such as selenocompounds, to counteract its harmful effects is still an interesting matter of investigation. In addition, selenocompounds seem to neutralise or minimize Hg toxicity by inducing changes in the distribution, deposition and excretion of Hg (de Freitas et al., 2009; Farina et al., 2011; Korbas et al., 2010), but the molecular mechanisms for the preventive activities of the selenocompounds related to MeHg-induced damage in the liver remain largely unknown. "
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    • "Schisandrin B (Sch B) is the most abundant active dibenzocyclooctadiene lignan, isolated from the fruit of Schisandra chinensis (Turcz) Baill, a traditional Chinese herb widely used as an hepatotonic , anti-diabetic, anti-inflammatory agent, devoid of collateral effects (Opletal et al., 2004; Guo et al., 2008). We reported earlier its efficacy against mercury-induced hepatotoxicity (Stacchiotti et al., 2009b) and Chiu et al. (2008b) demonstrated its beneficial role on renal mitochondria in gentamicin-induced nephrotoxicity in rat. In a recent biochemical study Liu et al. (2011) outlined the antioxidant potential of Sch B against mercury challenge in rats, but its effect on stress proteins and NOS enzymes is still unknown so we performed this in vivo and in vitro study. "
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