Reduction of Aflatoxin B₁ Toxicity by <i>Lactobacillus plantarum</i> C88: A Potential Probiotic Strain Isolated from Chinese Traditional Fermented Food “Tofu”

<div><p>In this study, we investigated the potential of <i>Lactobacillus plantarum</i> isolated from Chinese traditional fermented foods to reduce the toxicity of aflatoxin B₁ (AFB₁), and its subsequent detoxification mechanism. Among all the investigated <i>L</i>. <i>plantarum</i> strains, <i>L</i>. <i>plantarum</i> C88 showed the strongest AFB₁ binding capacity in vitro, and was orally administered to mice with liver oxidative damage induced by AFB₁. In the therapy groups, the mice that received <i>L</i>. <i>plantarum</i> C88, especially heat-killed <i>L</i>. <i>plantarum</i> C88, after a single dose of AFB₁ exposure, showed an increase in unabsorbed AFB₁ in the feces. Moreover, the effects of <i>L</i>. <i>plantarum</i> C88 on the enzymes and non-enzymes antioxidant abilities in serum and liver, histological alterations of liver were assayed. The results indicated that compared to the control group, <i>L</i>. <i>plantarum</i> C88 alone administration induced significant increase of antioxidant capacity, but did not induce any significant changes in the histological picture. Compared to the mice that received AFB₁ only, <i>L</i>. <i>plantarum</i> C88 treatment could weaken oxidative stress by enhancing the activity of antioxidant enzymes and elevating the expression of Glutathione S-transferase (GST) A3 through Nuclear factor erythroid (derived factor 2) related factor 2 (Nrf2) pathway. Furthermore, cytochrome P450 (CYP 450) 1A2 and CYP 3A4 expression was inhibited by <i>L</i>. <i>plantarum</i> C88, and urinary aflatoxin B₁-<i>N</i>^<i>7</i>-guanine (AFB-<i>N</i>^<i>7</i>-guanine), a AFB₁ metabolite formed by CYP 1A2 and CYP 3A4, was significantly reduced by the presence of viable <i>L</i>. <i>plantarum</i> C88. Meanwhile, the significant improvements were showed in histological pictures of the liver tissues in mice orally administered with viable <i>L</i>. <i>plantarum</i> C88. Collectively, <i>L</i>. <i>plantarum</i> C88 may alleviate AFB₁ toxicity by increasing fecal AFB₁ excretion, reversing deficits in antioxidant defense systems and regulating the metabolism of AFB₁.</p>